| a5321ae | Ashok Raj | 28 February 2018, 10:28:46 UTC | x86/microcode: Synchronize late microcode loading Original idea by Ashok, completely rewritten by Borislav. Before you read any further: the early loading method is still the preferred one and you should always do that. The following patch is improving the late loading mechanism for long running jobs and cloud use cases. Gather all cores and serialize the microcode update on them by doing it one-by-one to make the late update process as reliable as possible and avoid potential issues caused by the microcode update. [ Borislav: Rewrite completely. ] Co-developed-by: Borislav Petkov <bp@suse.de> Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: https://lkml.kernel.org/r/20180228102846.13447-8-bp@alien8.de | 08 March 2018, 09:19:26 UTC |
| cfb52a5 | Borislav Petkov | 28 February 2018, 10:28:45 UTC | x86/microcode: Request microcode on the BSP ... so that any newer version can land in the cache and can later be fished out by the application functions. Do that before grabbing the hotplug lock. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: https://lkml.kernel.org/r/20180228102846.13447-7-bp@alien8.de | 08 March 2018, 09:19:26 UTC |
| d8c3b52 | Borislav Petkov | 28 February 2018, 10:28:44 UTC | x86/microcode/intel: Look into the patch cache first The cache might contain a newer patch - look in there first. A follow-on change will make sure newest patches are loaded into the cache of microcode patches. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: https://lkml.kernel.org/r/20180228102846.13447-6-bp@alien8.de | 08 March 2018, 09:19:26 UTC |
| 30ec26d | Ashok Raj | 28 February 2018, 10:28:43 UTC | x86/microcode: Do not upload microcode if CPUs are offline Avoid loading microcode if any of the CPUs are offline, and issue a warning. Having different microcode revisions on the system at any time is outright dangerous. [ Borislav: Massage changelog. ] Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: http://lkml.kernel.org/r/1519352533-15992-4-git-send-email-ashok.raj@intel.com Link: https://lkml.kernel.org/r/20180228102846.13447-5-bp@alien8.de | 08 March 2018, 09:19:26 UTC |
| 91df9fd | Ashok Raj | 28 February 2018, 10:28:42 UTC | x86/microcode/intel: Writeback and invalidate caches before updating microcode Updating microcode is less error prone when caches have been flushed and depending on what exactly the microcode is updating. For example, some of the issues around certain Broadwell parts can be addressed by doing a full cache flush. [ Borislav: Massage it and use native_wbinvd() in both cases. ] Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: http://lkml.kernel.org/r/1519352533-15992-3-git-send-email-ashok.raj@intel.com Link: https://lkml.kernel.org/r/20180228102846.13447-4-bp@alien8.de | 08 March 2018, 09:19:25 UTC |
| c182d2b | Ashok Raj | 28 February 2018, 10:28:41 UTC | x86/microcode/intel: Check microcode revision before updating sibling threads After updating microcode on one of the threads of a core, the other thread sibling automatically gets the update since the microcode resources on a hyperthreaded core are shared between the two threads. Check the microcode revision on the CPU before performing a microcode update and thus save us the WRMSR 0x79 because it is a particularly expensive operation. [ Borislav: Massage changelog and coding style. ] Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: http://lkml.kernel.org/r/1519352533-15992-2-git-send-email-ashok.raj@intel.com Link: https://lkml.kernel.org/r/20180228102846.13447-3-bp@alien8.de | 08 March 2018, 09:19:25 UTC |
| 854857f | Borislav Petkov | 28 February 2018, 10:28:40 UTC | x86/microcode: Get rid of struct apply_microcode_ctx It is a useless remnant from earlier times. Use the ucode_state enum directly. No functional change. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Link: https://lkml.kernel.org/r/20180228102846.13447-2-bp@alien8.de | 08 March 2018, 09:19:25 UTC |
| 3626822 | Konrad Rzeszutek Wilk | 26 February 2018, 14:35:01 UTC | x86/spectre_v2: Don't check microcode versions when running under hypervisors As: 1) It's known that hypervisors lie about the environment anyhow (host mismatch) 2) Even if the hypervisor (Xen, KVM, VMWare, etc) provided a valid "correct" value, it all gets to be very murky when migration happens (do you provide the "new" microcode of the machine?). And in reality the cloud vendors are the ones that should make sure that the microcode that is running is correct and we should just sing lalalala and trust them. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Wanpeng Li <kernellwp@gmail.com> Cc: kvm <kvm@vger.kernel.org> Cc: Krčmář <rkrcmar@redhat.com> Cc: Borislav Petkov <bp@alien8.de> CC: "H. Peter Anvin" <hpa@zytor.com> CC: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180226213019.GE9497@char.us.oracle.com | 08 March 2018, 09:13:02 UTC |
| 076ca27 | Andy Lutomirski | 07 March 2018, 19:12:27 UTC | x86/vsyscall/64: Drop "native" vsyscalls Since Linux v3.2, vsyscalls have been deprecated and slow. From v3.2 on, Linux had three vsyscall modes: "native", "emulate", and "none". "emulate" is the default. All known user programs work correctly in emulate mode, but vsyscalls turn into page faults and are emulated. This is very slow. In "native" mode, the vsyscall page is easily usable as an exploit gadget, but vsyscalls are a bit faster -- they turn into normal syscalls. (This is in contrast to vDSO functions, which can be much faster than syscalls.) In "none" mode, there are no vsyscalls. For all practical purposes, "native" was really just a chicken bit in case something went wrong with the emulation. It's been over six years, and nothing has gone wrong. Delete it. Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Kernel Hardening <kernel-hardening@lists.openwall.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/519fee5268faea09ae550776ce969fa6e88668b0.1520449896.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> | 08 March 2018, 05:48:15 UTC |
| 91c5f0d | Dominik Brodowski | 06 March 2018, 21:18:09 UTC | x86/entry/64/compat: Save one instruction in entry_INT80_compat() As %rdi is never user except in the following push, there is no need to restore %rdi to the original value. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: luto@amacapital.net Cc: viro@zeniv.linux.org.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> | 07 March 2018, 06:57:31 UTC |
| af52201 | Dominik Brodowski | 06 March 2018, 21:18:08 UTC | x86/entry: Do not special-case clone(2) in compat entry With the CPU renaming registers on its own, and all the overhead of the syscall entry/exit, it is doubtful whether the compiled output of mov %r8, %rax mov %rcx, %r8 mov %rax, %rcx jmpq sys_clone is measurably slower than the hand-crafted version of xchg %r8, %rcx So get rid of this special case. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: luto@amacapital.net Cc: viro@zeniv.linux.org.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> | 07 March 2018, 06:57:31 UTC |
| 4ddb45d | Dominik Brodowski | 06 March 2018, 21:18:07 UTC | x86/syscalls: Use COMPAT_SYSCALL_DEFINEx() macros for x86-only compat syscalls While at it, convert declarations of type "unsigned" to "unsigned int". Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: luto@amacapital.net Cc: viro@zeniv.linux.org.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> | 07 March 2018, 06:57:30 UTC |
| 7c2178c | Dominik Brodowski | 06 March 2018, 21:18:05 UTC | x86/syscalls: Use proper syscall definition for sys_ioperm() Using SYSCALL_DEFINEx() is recommended, so use it also here. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: luto@amacapital.net Cc: viro@zeniv.linux.org.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> | 07 March 2018, 06:57:30 UTC |
| a41e2ab | Dominik Brodowski | 06 March 2018, 21:18:04 UTC | x86/entry: Remove stale syscall prototype sys32_vm86_warning() is long gone. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: luto@amacapital.net Cc: viro@zeniv.linux.org.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> | 07 March 2018, 06:57:30 UTC |
| b411991 | Dominik Brodowski | 06 March 2018, 21:18:03 UTC | x86/syscalls/32: Simplify $entry == $compat entries If the compat entry point is equivalent to the native entry point, it does not need to be specified explicitly. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: luto@amacapital.net Cc: viro@zeniv.linux.org.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> | 07 March 2018, 06:57:29 UTC |
| 63474dc | Josh Poimboeuf | 06 March 2018, 23:58:15 UTC | objtool: Fix 32-bit build Fix the objtool build when cross-compiling a 64-bit kernel on a 32-bit host. This also simplifies read_retpoline_hints() a bit and makes its implementation similar to most of the other annotation reading functions. Reported-by: Sven Joachim <svenjoac@gmx.de> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: b5bc2231b8ad ("objtool: Add retpoline validation") Link: http://lkml.kernel.org/r/2ca46c636c23aa9c9d57d53c75de4ee3ddf7a7df.1520380691.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 07 March 2018, 06:50:38 UTC |
| 945fd17 | Thomas Gleixner | 28 February 2018, 20:14:26 UTC | x86/cpu_entry_area: Sync cpu_entry_area to initial_page_table The separation of the cpu_entry_area from the fixmap missed the fact that on 32bit non-PAE kernels the cpu_entry_area mapping might not be covered in initial_page_table by the previous synchronizations. This results in suspend/resume failures because 32bit utilizes initial page table for resume. The absence of the cpu_entry_area mapping results in a triple fault, aka. insta reboot. With PAE enabled this works by chance because the PGD entry which covers the fixmap and other parts incindentally provides the cpu_entry_area mapping as well. Synchronize the initial page table after setting up the cpu entry area. Instead of adding yet another copy of the same code, move it to a function and invoke it from the various places. It needs to be investigated if the existing calls in setup_arch() and setup_per_cpu_areas() can be replaced by the later invocation from setup_cpu_entry_areas(), but that's beyond the scope of this fix. Fixes: 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap") Reported-by: Woody Suwalski <terraluna977@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Woody Suwalski <terraluna977@gmail.com> Cc: William Grant <william.grant@canonical.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1802282137290.1392@nanos.tec.linutronix.de | 01 March 2018, 08:48:27 UTC |
| 1402fd8 | Josh Poimboeuf | 28 February 2018, 13:19:21 UTC | objtool: Fix another switch table detection issue Continue the switch table detection whack-a-mole. Add a check to distinguish KASAN data reads from switch data reads. The switch jump tables in .rodata have relocations associated with them. This fixes the following warning: crypto/asymmetric_keys/x509_cert_parser.o: warning: objtool: x509_note_pkey_algo()+0xa4: sibling call from callable instruction with modified stack frame Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Arnd Bergmann <arnd@arndb.de> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/d7c8853022ad47d158cb81e953a40469fc08a95e.1519784382.git.jpoimboe@redhat.com | 28 February 2018, 15:03:19 UTC |
| 71c208d | Juergen Gross | 26 February 2018, 14:08:18 UTC | x86/xen: Zero MSR_IA32_SPEC_CTRL before suspend Older Xen versions (4.5 and before) might have problems migrating pv guests with MSR_IA32_SPEC_CTRL having a non-zero value. So before suspending zero that MSR and restore it after being resumed. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jan Beulich <jbeulich@suse.com> Cc: stable@vger.kernel.org Cc: xen-devel@lists.xenproject.org Cc: boris.ostrovsky@oracle.com Link: https://lkml.kernel.org/r/20180226140818.4849-1-jgross@suse.com | 28 February 2018, 15:03:19 UTC |
| 946fbbc | Paolo Bonzini | 22 February 2018, 15:43:18 UTC | KVM/VMX: Optimize vmx_vcpu_run() and svm_vcpu_run() by marking the RDMSR path as unlikely() vmx_vcpu_run() and svm_vcpu_run() are large functions, and giving branch hints to the compiler can actually make a substantial cycle difference by keeping the fast path contiguous in memory. With this optimization, the retpoline-guest/retpoline-host case is about 50 cycles faster. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Jim Mattson <jmattson@google.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: KarimAllah Ahmed <karahmed@amazon.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm@vger.kernel.org Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20180222154318.20361-3-pbonzini@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 23 February 2018, 07:24:36 UTC |
| ecb586b | Paolo Bonzini | 22 February 2018, 15:43:17 UTC | KVM/x86: Remove indirect MSR op calls from SPEC_CTRL Having a paravirt indirect call in the IBRS restore path is not a good idea, since we are trying to protect from speculative execution of bogus indirect branch targets. It is also slower, so use native_wrmsrl() on the vmentry path too. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Jim Mattson <jmattson@google.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: KarimAllah Ahmed <karahmed@amazon.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm@vger.kernel.org Cc: stable@vger.kernel.org Fixes: d28b387fb74da95d69d2615732f50cceb38e9a4d Link: http://lkml.kernel.org/r/20180222154318.20361-2-pbonzini@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 23 February 2018, 07:24:35 UTC |
| d5028ba | Peter Zijlstra | 06 February 2018, 08:46:13 UTC | objtool, retpolines: Integrate objtool with retpoline support more closely Disable retpoline validation in objtool if your compiler sucks, and otherwise select the validation stuff for CONFIG_RETPOLINE=y (most builds would already have it set due to ORC). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:32 UTC |
| 0ca7d5b | Josh Poimboeuf | 21 February 2018, 02:42:14 UTC | x86/entry/64: Simplify ENCODE_FRAME_POINTER On 64-bit, the stack pointer is always aligned on interrupt, so instead of setting the LSB of the pt_regs address, we can just add 1 to it. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrew Lutomirski <luto@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180221024214.lhl5jfgw33c4vz3m@treble Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:07 UTC |
| 9fbcc57 | Josh Poimboeuf | 20 February 2018, 17:37:53 UTC | extable: Make init_kernel_text() global Convert init_kernel_text() to a global function and use it in a few places instead of manually comparing _sinittext and _einittext. Note that kallsyms.h has a very similar function called is_kernel_inittext(), but its end check is inclusive. I'm not sure whether that's intentional behavior, so I didn't touch it. Suggested-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/4335d02be8d45ca7d265d2f174251d0b7ee6c5fd.1519051220.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:06 UTC |
| dc1dd18 | Josh Poimboeuf | 20 February 2018, 17:37:52 UTC | jump_label: Warn on failed jump_label patching attempt Currently when the jump label code encounters an address which isn't recognized by kernel_text_address(), it just silently fails. This can be dangerous because jump labels are used in a variety of places, and are generally expected to work. Convert the silent failure to a warning. This won't warn about attempted writes to tracepoints in __init code after initmem has been freed, as those are already guarded by the entry->code check. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@suse.de> Cc: Jason Baron <jbaron@akamai.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/de3a271c93807adb7ed48f4e946b4f9156617680.1519051220.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:06 UTC |
| 3335224 | Josh Poimboeuf | 20 February 2018, 17:37:51 UTC | jump_label: Explicitly disable jump labels in __init code After initmem has been freed, any jump labels in __init code are prevented from being written to by the kernel_text_address() check in __jump_label_update(). However, this check is quite broad. If kernel_text_address() were to return false for any other reason, the jump label write would fail silently with no warning. For jump labels in module init code, entry->code is set to zero to indicate that the entry is disabled. Do the same thing for core kernel init code. This makes the behavior more consistent, and will also make it more straightforward to detect non-init jump label write failures in the next patch. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@suse.de> Cc: Jason Baron <jbaron@akamai.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/c52825c73f3a174e8398b6898284ec20d4deb126.1519051220.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:05 UTC |
| f3d415e | Dominik Brodowski | 20 February 2018, 21:01:13 UTC | x86/entry/64: Open-code switch_to_thread_stack() Open-code the two instances which called switch_to_thread_stack(). This allows us to remove the wrapper around DO_SWITCH_TO_THREAD_STACK. While at it, update the UNWIND hint to reflect where the IRET frame is, and update the commentary to reflect what we are actually doing here. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180220210113.6725-7-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:05 UTC |
| b2855d8 | Dominik Brodowski | 20 February 2018, 21:01:12 UTC | x86/entry/64: Move ASM_CLAC to interrupt_entry() Moving ASM_CLAC to interrupt_entry means two instructions (addq / pushq and call interrupt_entry) are not covered by it. However, it offers a noticeable size reduction (-.2k): text data bss dec hex filename 16882 0 0 16882 41f2 entry_64.o-orig 16623 0 0 16623 40ef entry_64.o Suggested-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180220210113.6725-6-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:05 UTC |
| 3aa99fc | Dominik Brodowski | 20 February 2018, 21:01:11 UTC | x86/entry/64: Remove 'interrupt' macro It is now trivial to call interrupt_entry() and then the actual worker. Therefore, remove the interrupt macro and open code it all. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180220210113.6725-5-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:04 UTC |
| 90a6acc | Dominik Brodowski | 20 February 2018, 21:01:10 UTC | x86/entry/64: Move the switch_to_thread_stack() call to interrupt_entry() We can also move the CLD, SWAPGS, and the switch_to_thread_stack() call to the interrupt_entry() helper function. As we do not want call depths of two, convert switch_to_thread_stack() to a macro. However, switch_to_thread_stack() has another user in entry_64_compat.S, which currently expects it to be a function. To keep the code changes in this patch minimal, create a wrapper function. The switch to a macro means that there is some binary code duplication if CONFIG_IA32_EMULATION=y is enabled. Therefore, the size reduction differs whether CONFIG_IA32_EMULATION is enabled or not: CONFIG_IA32_EMULATION=y (-0.13k): text data bss dec hex filename 17158 0 0 17158 4306 entry_64.o-orig 17028 0 0 17028 4284 entry_64.o CONFIG_IA32_EMULATION=n (-0.27k): text data bss dec hex filename 17158 0 0 17158 4306 entry_64.o-orig 16882 0 0 16882 41f2 entry_64.o Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180220210113.6725-4-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:04 UTC |
| 2ba6474 | Dominik Brodowski | 20 February 2018, 21:01:09 UTC | x86/entry/64: Move ENTER_IRQ_STACK from interrupt macro to interrupt_entry Moving the switch to IRQ stack from the interrupt macro to the helper function requires some trickery: All ENTER_IRQ_STACK really cares about is where the "original" stack -- meaning the GP registers etc. -- is stored. Therefore, we need to offset the stored RSP value by 8 whenever ENTER_IRQ_STACK is called from within a function. In such cases, and after switching to the IRQ stack, we need to push the "original" return address (i.e. the return address from the call to the interrupt entry function) to the IRQ stack. This trickery allows us to carve another .85k from the text size (it would be more except for the additional unwind hints): text data bss dec hex filename 18006 0 0 18006 4656 entry_64.o-orig 17158 0 0 17158 4306 entry_64.o Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180220210113.6725-3-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:03 UTC |
| 0e34d22 | Dominik Brodowski | 20 February 2018, 21:01:08 UTC | x86/entry/64: Move PUSH_AND_CLEAR_REGS from interrupt macro to helper function The PUSH_AND_CLEAR_REGS macro is able to insert the GP registers "above" the original return address. This allows us to move a sizeable part of the interrupt entry macro to an interrupt entry helper function: text data bss dec hex filename 21088 0 0 21088 5260 entry_64.o-orig 18006 0 0 18006 4656 entry_64.o Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180220210113.6725-2-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:03 UTC |
| d72f4e2 | Ingo Molnar | 21 February 2018, 08:20:37 UTC | x86/speculation: Move firmware_restrict_branch_speculation_*() from C to CPP firmware_restrict_branch_speculation_*() recently started using preempt_enable()/disable(), but those are relatively high level primitives and cause build failures on some 32-bit builds. Since we want to keep <asm/nospec-branch.h> low level, convert them to macros to avoid header hell... Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: arjan.van.de.ven@intel.com Cc: bp@alien8.de Cc: dave.hansen@intel.com Cc: jmattson@google.com Cc: karahmed@amazon.de Cc: kvm@vger.kernel.org Cc: pbonzini@redhat.com Cc: rkrcmar@redhat.com Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 15:54:03 UTC |
| ca41b97 | Peter Zijlstra | 31 January 2018, 09:18:28 UTC | objtool: Add module specific retpoline rules David allowed retpolines in .init.text, except for modules, which will trip up objtool retpoline validation, fix that. Requested-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 08:05:05 UTC |
| b5bc223 | Peter Zijlstra | 16 January 2018, 09:24:06 UTC | objtool: Add retpoline validation David requested a objtool validation pass for CONFIG_RETPOLINE=y enabled builds, where it validates no unannotated indirect jumps or calls are left. Add an additional .discard.retpoline_safe section to allow annotating the few indirect sites that are required and safe. Requested-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 08:05:04 UTC |
| 43a4525 | Peter Zijlstra | 16 January 2018, 16:16:32 UTC | objtool: Use existing global variables for options Use the existing global variables instead of passing them around and creating duplicate global variables. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 08:05:04 UTC |
| 531bb52 | Peter Zijlstra | 23 January 2018, 15:18:50 UTC | x86/mm/sme, objtool: Annotate indirect call in sme_encrypt_execute() This is boot code and thus Spectre-safe: we run this _way_ before userspace comes along to have a chance to poison our branch predictor. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 08:05:04 UTC |
| bd89004 | Peter Zijlstra | 16 January 2018, 09:38:09 UTC | x86/boot, objtool: Annotate indirect jump in secondary_startup_64() The objtool retpoline validation found this indirect jump. Seeing how it's on CPU bringup before we run userspace it should be safe, annotate it. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 08:05:03 UTC |
| 3010a06 | Peter Zijlstra | 17 January 2018, 15:58:11 UTC | x86/paravirt, objtool: Annotate indirect calls Paravirt emits indirect calls which get flagged by objtool retpoline checks, annotate it away because all these indirect calls will be patched out before we start userspace. This patching happens through alternative_instructions() -> apply_paravirt() -> pv_init_ops.patch() which will eventually end up in paravirt_patch_default(). This function _will_ write direct alternatives. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 08:05:03 UTC |
| 9e0e3c5 | Peter Zijlstra | 17 January 2018, 21:34:34 UTC | x86/speculation, objtool: Annotate indirect calls/jumps for objtool Annotate the indirect calls/jumps in the CALL_NOSPEC/JUMP_NOSPEC alternatives. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> | 21 February 2018, 08:05:03 UTC |
| 8735871 | David Woodhouse | 19 February 2018, 10:50:57 UTC | x86/retpoline: Support retpoline builds with Clang Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: arjan.van.de.ven@intel.com Cc: bp@alien8.de Cc: dave.hansen@intel.com Cc: jmattson@google.com Cc: karahmed@amazon.de Cc: kvm@vger.kernel.org Cc: pbonzini@redhat.com Cc: rkrcmar@redhat.com Link: http://lkml.kernel.org/r/1519037457-7643-5-git-send-email-dwmw@amazon.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> | 20 February 2018, 10:17:58 UTC |
| dd84441 | David Woodhouse | 19 February 2018, 10:50:54 UTC | x86/speculation: Use IBRS if available before calling into firmware Retpoline means the kernel is safe because it has no indirect branches. But firmware isn't, so use IBRS for firmware calls if it's available. Block preemption while IBRS is set, although in practice the call sites already had to be doing that. Ignore hpwdt.c for now. It's taking spinlocks and calling into firmware code, from an NMI handler. I don't want to touch that with a bargepole. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: arjan.van.de.ven@intel.com Cc: bp@alien8.de Cc: dave.hansen@intel.com Cc: jmattson@google.com Cc: karahmed@amazon.de Cc: kvm@vger.kernel.org Cc: pbonzini@redhat.com Cc: rkrcmar@redhat.com Link: http://lkml.kernel.org/r/1519037457-7643-2-git-send-email-dwmw@amazon.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> | 20 February 2018, 08:38:33 UTC |
| d1c9910 | David Woodhouse | 19 February 2018, 10:50:56 UTC | Revert "x86/retpoline: Simplify vmexit_fill_RSB()" This reverts commit 1dde7415e99933bb7293d6b2843752cbdb43ec11. By putting the RSB filling out of line and calling it, we waste one RSB slot for returning from the function itself, which means one fewer actual function call we can make if we're doing the Skylake abomination of call-depth counting. It also changed the number of RSB stuffings we do on vmexit from 32, which was correct, to 16. Let's just stop with the bikeshedding; it didn't actually *fix* anything anyway. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: arjan.van.de.ven@intel.com Cc: bp@alien8.de Cc: dave.hansen@intel.com Cc: jmattson@google.com Cc: karahmed@amazon.de Cc: kvm@vger.kernel.org Cc: pbonzini@redhat.com Cc: rkrcmar@redhat.com Link: http://lkml.kernel.org/r/1519037457-7643-4-git-send-email-dwmw@amazon.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> | 20 February 2018, 08:38:26 UTC |
| 8554004 | Jan Beulich | 19 February 2018, 15:06:14 UTC | x86-64/realmode: Add instruction suffix Omitting suffixes from instructions in AT&T mode is bad practice when operand size cannot be determined by the assembler from register operands, and is likely going to be warned about by upstream GAS in the future (mine does already). Add the single missing suffix here. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/5A8AF5F602000078001A9230@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 20 February 2018, 08:33:41 UTC |
| f2f18b1 | Jan Beulich | 19 February 2018, 14:52:10 UTC | x86/LDT: Avoid warning in 32-bit builds with older gcc BUG() doesn't always imply "no return", and hence should be followed by a return statement even if that's obviously (to a human) unreachable. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/5A8AF2AA02000078001A91E9@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 20 February 2018, 08:33:40 UTC |
| 6262b6e | Jan Beulich | 19 February 2018, 14:50:23 UTC | x86/IO-APIC: Avoid warning in 32-bit builds Constants wider than 32 bits should be tagged with ULL. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/5A8AF23F02000078001A91E5@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 20 February 2018, 08:33:40 UTC |
| 700b7c5 | Jan Beulich | 19 February 2018, 14:49:12 UTC | x86/asm: Improve how GEN_*_SUFFIXED_RMWcc() specify clobbers Commit: df3405245a ("x86/asm: Add suffix macro for GEN_*_RMWcc()") ... introduced "suffix" RMWcc operations, adding bogus clobber specifiers: For one, on x86 there's no point explicitly clobbering "cc". In fact, with GCC properly fixed, this results in an overlap being detected by the compiler between outputs and clobbers. Furthermore it seems bad practice to me to have clobber specification and use of the clobbered register(s) disconnected - it should rather be at the invocation place of that GEN_{UN,BIN}ARY_SUFFIXED_RMWcc() macros that the clobber is specified which this particular invocation needs. Drop the "cc" clobber altogether and move the "cx" one to refcount.h. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/5A8AF1F802000078001A91E1@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 20 February 2018, 08:33:39 UTC |
| 3b3a926 | Jann Horn | 19 February 2018, 17:50:39 UTC | x86/mm: Remove stale comment about KMEMCHECK This comment referred to a conditional call to kmemcheck_hide() that was here until commit 4950276672fc ("kmemcheck: remove annotations"). Now that kmemcheck has been removed, it doesn't make sense anymore. Signed-off-by: Jann Horn <jannh@google.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20180219175039.253089-1-jannh@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 20 February 2018, 08:33:39 UTC |
| 842cef9 | Jan Beulich | 19 February 2018, 14:48:11 UTC | x86/mm: Fix {pmd,pud}_{set,clear}_flags() Just like pte_{set,clear}_flags() their PMD and PUD counterparts should not do any address translation. This was outright wrong under Xen (causing a dead boot with no useful output on "suitable" systems), and produced needlessly more complicated code (even if just slightly) when paravirt was enabled. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/5A8AF1BB02000078001A91C3@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 20 February 2018, 08:33:39 UTC |
| ced5d0b | Dominik Brodowski | 14 February 2018, 17:59:24 UTC | x86/entry/64: Use 'xorl' for faster register clearing On some x86 CPU microarchitectures using 'xorq' to clear general-purpose registers is slower than 'xorl'. As 'xorl' is sufficient to clear all 64 bits of these registers due to zero-extension [*], switch the x86 64-bit entry code to use 'xorl'. No change in functionality and no change in code size. [*] According to Intel 64 and IA-32 Architecture Software Developer's Manual, section 3.4.1.1, the result of 32-bit operands are "zero- extended to a 64-bit result in the destination general-purpose register." The AMD64 Architecture Programmer’s Manual Volume 3, Appendix B.1, describes the same behaviour. Suggested-by: Denys Vlasenko <dvlasenk@redhat.com> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180214175924.23065-3-linux@dominikbrodowski.net [ Improved on the changelog a bit. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> | 17 February 2018, 10:14:33 UTC |
| 9e809d1 | Dominik Brodowski | 14 February 2018, 17:59:23 UTC | x86/entry: Reduce the code footprint of the 'idtentry' macro Play a little trick in the generic PUSH_AND_CLEAR_REGS macro to insert the GP registers "above" the original return address. This allows us to (re-)insert the macro in error_entry() and paranoid_entry() and to remove it from the idtentry macro. This reduces the static footprint significantly: text data bss dec hex filename 24307 0 0 24307 5ef3 entry_64.o-orig 20987 0 0 20987 51fb entry_64.o Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180214175924.23065-2-linux@dominikbrodowski.net [ Small tweaks to comments. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> | 17 February 2018, 10:14:33 UTC |
| 42ca808 | Borislav Petkov | 16 February 2018, 11:26:40 UTC | x86/CPU: Check CPU feature bits after microcode upgrade With some microcode upgrades, new CPUID features can become visible on the CPU. Check what the kernel has mirrored now and issue a warning hinting at possible things the user/admin can do to make use of the newly visible features. Originally-by: Ashok Raj <ashok.raj@intel.com> Tested-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180216112640.11554-4-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org> | 17 February 2018, 07:43:55 UTC |
| 1008c52 | Borislav Petkov | 16 February 2018, 11:26:39 UTC | x86/CPU: Add a microcode loader callback Add a callback function which the microcode loader calls when microcode has been updated to a newer revision. Do the callback only when no error was encountered during loading. Tested-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180216112640.11554-3-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org> | 17 February 2018, 07:43:55 UTC |
| 3f1f576 | Borislav Petkov | 16 February 2018, 11:26:38 UTC | x86/microcode: Propagate return value from updating functions ... so that callers can know when microcode was updated and act accordingly. Tested-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180216112640.11554-2-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org> | 17 February 2018, 07:43:55 UTC |
| eb6174f | Dan Williams | 16 February 2018, 21:20:54 UTC | nospec: Include <asm/barrier.h> dependency The nospec.h header expects the per-architecture header file <asm/barrier.h> to optionally define array_index_mask_nospec(). Include that dependency to prevent inadvertent fallback to the default array_index_mask_nospec() implementation. The default implementation may not provide a full mitigation on architectures that perform data value speculation. Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/151881605404.17395.1341935530792574707.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 17 February 2018, 07:40:59 UTC |
| b98c6a1 | Rasmus Villemoes | 16 February 2018, 21:20:48 UTC | nospec: Allow index argument to have const-qualified type The last expression in a statement expression need not be a bare variable, quoting gcc docs The last thing in the compound statement should be an expression followed by a semicolon; the value of this subexpression serves as the value of the entire construct. and we already use that in e.g. the min/max macros which end with a ternary expression. This way, we can allow index to have const-qualified type, which will in some cases avoid the need for introducing a local copy of index of non-const qualified type. That, in turn, can prevent readers not familiar with the internals of array_index_nospec from wondering about the seemingly redundant extra variable, and I think that's worthwhile considering how confusing the whole _nospec business is. The expression _i&_mask has type unsigned long (since that is the type of _mask, and the BUILD_BUG_ONs guarantee that _i will get promoted to that), so in order not to change the type of the whole expression, add a cast back to typeof(_i). Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arch@vger.kernel.org Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/151881604837.17395.10812767547837568328.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 17 February 2018, 07:40:59 UTC |
| 1d91c1d | Dan Williams | 16 February 2018, 21:20:42 UTC | nospec: Kill array_index_nospec_mask_check() There are multiple problems with the dynamic sanity checking in array_index_nospec_mask_check(): * It causes unnecessary overhead in the 32-bit case since integer sized @index values will no longer cause the check to be compiled away like in the 64-bit case. * In the 32-bit case it may trigger with user controllable input when the expectation is that should only trigger during development of new kernel enabling. * The macro reuses the input parameter in multiple locations which is broken if someone passes an expression like 'index++' to array_index_nospec(). Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/151881604278.17395.6605847763178076520.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 17 February 2018, 07:40:59 UTC |
| d4667ca | Linus Torvalds | 15 February 2018, 01:02:15 UTC | Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 PTI and Spectre related fixes and updates from Ingo Molnar: "Here's the latest set of Spectre and PTI related fixes and updates: Spectre: - Add entry code register clearing to reduce the Spectre attack surface - Update the Spectre microcode blacklist - Inline the KVM Spectre helpers to get close to v4.14 performance again. - Fix indirect_branch_prediction_barrier() - Fix/improve Spectre related kernel messages - Fix array_index_nospec_mask() asm constraint - KVM: fix two MSR handling bugs PTI: - Fix a paranoid entry PTI CR3 handling bug - Fix comments objtool: - Fix paranoid_entry() frame pointer warning - Annotate WARN()-related UD2 as reachable - Various fixes - Add Add Peter Zijlstra as objtool co-maintainer Misc: - Various x86 entry code self-test fixes - Improve/simplify entry code stack frame generation and handling after recent heavy-handed PTI and Spectre changes. (There's two more WIP improvements expected here.) - Type fix for cache entries There's also some low risk non-fix changes I've included in this branch to reduce backporting conflicts: - rename a confusing x86_cpu field name - de-obfuscate the naming of single-TLB flushing primitives" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits) x86/entry/64: Fix CR3 restore in paranoid_exit() x86/cpu: Change type of x86_cache_size variable to unsigned int x86/spectre: Fix an error message x86/cpu: Rename cpu_data.x86_mask to cpu_data.x86_stepping selftests/x86/mpx: Fix incorrect bounds with old _sigfault x86/mm: Rename flush_tlb_single() and flush_tlb_one() to __flush_tlb_one_[user|kernel]() x86/speculation: Add <asm/msr-index.h> dependency nospec: Move array_index_nospec() parameter checking into separate macro x86/speculation: Fix up array_index_nospec_mask() asm constraint x86/debug: Use UD2 for WARN() x86/debug, objtool: Annotate WARN()-related UD2 as reachable objtool: Fix segfault in ignore_unreachable_insn() selftests/x86: Disable tests requiring 32-bit support on pure 64-bit systems selftests/x86: Do not rely on "int $0x80" in single_step_syscall.c selftests/x86: Do not rely on "int $0x80" in test_mremap_vdso.c selftests/x86: Fix build bug caused by the 5lvl test which has been moved to the VM directory selftests/x86/pkeys: Remove unused functions selftests/x86: Clean up and document sscanf() usage selftests/x86: Fix vDSO selftest segfault for vsyscall=none x86/entry/64: Remove the unused 'icebp' macro ... | 15 February 2018, 01:02:15 UTC |
| e486575 | Ingo Molnar | 14 February 2018, 07:39:11 UTC | x86/entry/64: Fix CR3 restore in paranoid_exit() Josh Poimboeuf noticed the following bug: "The paranoid exit code only restores the saved CR3 when it switches back to the user GS. However, even in the kernel GS case, it's possible that it needs to restore a user CR3, if for example, the paranoid exception occurred in the syscall exit path between SWITCH_TO_USER_CR3_STACK and SWAPGS." Josh also confirmed via targeted testing that it's possible to hit this bug. Fix the bug by also restoring CR3 in the paranoid_exit_no_swapgs branch. The reason we haven't seen this bug reported by users yet is probably because "paranoid" entry points are limited to the following cases: idtentry double_fault do_double_fault has_error_code=1 paranoid=2 idtentry debug do_debug has_error_code=0 paranoid=1 shift_ist=DEBUG_STACK idtentry int3 do_int3 has_error_code=0 paranoid=1 shift_ist=DEBUG_STACK idtentry machine_check do_mce has_error_code=0 paranoid=1 Amongst those entry points only machine_check is one that will interrupt an IRQS-off critical section asynchronously - and machine check events are rare. The other main asynchronous entries are NMI entries, which can be very high-freq with perf profiling, but they are special: they don't use the 'idtentry' macro but are open coded and restore user CR3 unconditionally so don't have this bug. Reported-and-tested-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Andy Lutomirski <luto@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20180214073910.boevmg65upbk3vqb@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:54 UTC |
| 24dbc60 | Gustavo A. R. Silva | 13 February 2018, 19:22:08 UTC | x86/cpu: Change type of x86_cache_size variable to unsigned int Currently, x86_cache_size is of type int, which makes no sense as we will never have a valid cache size equal or less than 0. So instead of initializing this variable to -1, it can perfectly be initialized to 0 and use it as an unsigned variable instead. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Addresses-Coverity-ID: 1464429 Link: http://lkml.kernel.org/r/20180213192208.GA26414@embeddedor.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:53 UTC |
| 9de29ea | Dan Carpenter | 14 February 2018, 07:14:17 UTC | x86/spectre: Fix an error message If i == ARRAY_SIZE(mitigation_options) then we accidentally print garbage from one space beyond the end of the mitigation_options[] array. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: KarimAllah Ahmed <karahmed@amazon.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-janitors@vger.kernel.org Fixes: 9005c6834c0f ("x86/spectre: Simplify spectre_v2 command line parsing") Link: http://lkml.kernel.org/r/20180214071416.GA26677@mwanda Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:53 UTC |
| b399151 | Jia Zhang | 01 January 2018, 01:52:10 UTC | x86/cpu: Rename cpu_data.x86_mask to cpu_data.x86_stepping x86_mask is a confusing name which is hard to associate with the processor's stepping. Additionally, correct an indent issue in lib/cpu.c. Signed-off-by: Jia Zhang <qianyue.zj@alibaba-inc.com> [ Updated it to more recent kernels. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: tony.luck@intel.com Link: http://lkml.kernel.org/r/1514771530-70829-1-git-send-email-qianyue.zj@alibaba-inc.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:52 UTC |
| 961888b | Rui Wang | 18 December 2017, 08:34:10 UTC | selftests/x86/mpx: Fix incorrect bounds with old _sigfault For distributions with old userspace header files, the _sigfault structure is different. mpx-mini-test fails with the following error: [root@Purley]# mpx-mini-test_64 tabletest XSAVE is supported by HW & OS XSAVE processor supported state mask: 0x2ff XSAVE OS supported state mask: 0x2ff BNDREGS: size: 64 user: 1 supervisor: 0 aligned: 0 BNDCSR: size: 64 user: 1 supervisor: 0 aligned: 0 starting mpx bounds table test ERROR: siginfo bounds do not match shadow bounds for register 0 Fix it by using the correct offset of _lower/_upper in _sigfault. RHEL needs this patch to work. Signed-off-by: Rui Wang <rui.y.wang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave.hansen@linux.intel.com Fixes: e754aedc26ef ("x86/mpx, selftests: Add MPX self test") Link: http://lkml.kernel.org/r/1513586050-1641-1-git-send-email-rui.y.wang@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:52 UTC |
| 1299ef1 | Andy Lutomirski | 31 January 2018, 16:03:10 UTC | x86/mm: Rename flush_tlb_single() and flush_tlb_one() to __flush_tlb_one_[user|kernel]() flush_tlb_single() and flush_tlb_one() sound almost identical, but they really mean "flush one user translation" and "flush one kernel translation". Rename them to flush_tlb_one_user() and flush_tlb_one_kernel() to make the semantics more obvious. [ I was looking at some PTI-related code, and the flush-one-address code is unnecessarily hard to understand because the names of the helpers are uninformative. This came up during PTI review, but no one got around to doing it. ] Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Eduardo Valentin <eduval@amazon.com> Cc: Hugh Dickins <hughd@google.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Linux-MM <linux-mm@kvack.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/3303b02e3c3d049dc5235d5651e0ae6d29a34354.1517414378.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:52 UTC |
| ea00f30 | Peter Zijlstra | 13 February 2018, 13:28:19 UTC | x86/speculation: Add <asm/msr-index.h> dependency Joe Konno reported a compile failure resulting from using an MSR without inclusion of <asm/msr-index.h>, and while the current code builds fine (by accident) this needs fixing for future patches. Reported-by: Joe Konno <joe.konno@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: arjan@linux.intel.com Cc: bp@alien8.de Cc: dan.j.williams@intel.com Cc: dave.hansen@linux.intel.com Cc: dwmw2@infradead.org Cc: dwmw@amazon.co.uk Cc: gregkh@linuxfoundation.org Cc: hpa@zytor.com Cc: jpoimboe@redhat.com Cc: linux-tip-commits@vger.kernel.org Cc: luto@kernel.org Fixes: 20ffa1caecca ("x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support") Link: http://lkml.kernel.org/r/20180213132819.GJ25201@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:51 UTC |
| 8fa80c5 | Will Deacon | 05 February 2018, 14:16:06 UTC | nospec: Move array_index_nospec() parameter checking into separate macro For architectures providing their own implementation of array_index_mask_nospec() in asm/barrier.h, attempting to use WARN_ONCE() to complain about out-of-range parameters using WARN_ON() results in a mess of mutually-dependent include files. Rather than unpick the dependencies, simply have the core code in nospec.h perform the checking for us. Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1517840166-15399-1-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:51 UTC |
| be3233f | Dan Williams | 07 February 2018, 02:22:40 UTC | x86/speculation: Fix up array_index_nospec_mask() asm constraint Allow the compiler to handle @size as an immediate value or memory directly rather than allocating a register. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/151797010204.1289.1510000292250184993.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:50 UTC |
| 3b3a371 | Peter Zijlstra | 09 February 2018, 12:16:59 UTC | x86/debug: Use UD2 for WARN() Since the Intel SDM added an ModR/M byte to UD0 and binutils followed that specification, we now cannot disassemble our kernel anymore. This now means Intel and AMD disagree on the encoding of UD0. And instead of playing games with additional bytes that are valid ModR/M and single byte instructions (0xd6 for instance), simply use UD2 for both WARN() and BUG(). Requested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180208194406.GD25181@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:50 UTC |
| 2b5db66 | Josh Poimboeuf | 08 February 2018, 23:09:26 UTC | x86/debug, objtool: Annotate WARN()-related UD2 as reachable By default, objtool assumes that a UD2 is a dead end. This is mainly because GCC 7+ sometimes inserts a UD2 when it detects a divide-by-zero condition. Now that WARN() is moving back to UD2, annotate the code after it as reachable so objtool can follow the code flow. Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kbuild test robot <fengguang.wu@intel.com> Link: http://lkml.kernel.org/r/0e483379275a42626ba8898117f918e1bf661e40.1518130694.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:49 UTC |
| fe24e27 | Josh Poimboeuf | 08 February 2018, 23:09:25 UTC | objtool: Fix segfault in ignore_unreachable_insn() Peter Zijlstra's patch for converting WARN() to use UD2 triggered a bunch of false "unreachable instruction" warnings, which then triggered a seg fault in ignore_unreachable_insn(). The seg fault happened when it tried to dereference a NULL 'insn->func' pointer. Thanks to static_cpu_has(), some functions can jump to a non-function area in the .altinstr_aux section. That breaks ignore_unreachable_insn()'s assumption that it's always inside the original function. Make sure ignore_unreachable_insn() only follows jumps within the current function. Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kbuild test robot <fengguang.wu@intel.com> Link: http://lkml.kernel.org/r/bace77a60d5af9b45eddb8f8fb9c776c8de657ef.1518130694.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:49 UTC |
| 9279ddf | Dominik Brodowski | 13 February 2018, 08:15:19 UTC | selftests/x86: Disable tests requiring 32-bit support on pure 64-bit systems The ldt_gdt and ptrace_syscall selftests, even in their 64-bit variant, use hard-coded 32-bit syscall numbers and call "int $0x80". This will fail on 64-bit systems with CONFIG_IA32_EMULATION=y disabled. Therefore, do not build these tests if we cannot build 32-bit binaries (which should be a good approximation for CONFIG_IA32_EMULATION=y being enabled). Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dmitry Safonov <dsafonov@virtuozzo.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kselftest@vger.kernel.org Cc: shuah@kernel.org Link: http://lkml.kernel.org/r/20180211111013.16888-6-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:48 UTC |
| 4105c69 | Dominik Brodowski | 13 February 2018, 08:13:21 UTC | selftests/x86: Do not rely on "int $0x80" in single_step_syscall.c On 64-bit builds, we should not rely on "int $0x80" working (it only does if CONFIG_IA32_EMULATION=y is enabled). To keep the "Set TF and check int80" test running on 64-bit installs with CONFIG_IA32_EMULATION=y enabled, build this test only if we can also build 32-bit binaries (which should be a good approximation for that). Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dmitry Safonov <dsafonov@virtuozzo.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kselftest@vger.kernel.org Cc: shuah@kernel.org Link: http://lkml.kernel.org/r/20180211111013.16888-5-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 15 February 2018, 00:15:48 UTC |
| 6556677 | Linus Torvalds | 14 February 2018, 18:14:59 UTC | Merge tag 'gfs2-4.16.rc1.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2 Pull gfs2 fix from Bob Peterson: "Fix regressions in the gfs2 iomap for block_map implementation we recently discovered in commit 3974320ca6" * tag 'gfs2-4.16.rc1.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: gfs2: Fixes to "Implement iomap for block_map" | 14 February 2018, 18:14:59 UTC |
| 694a20d | Linus Torvalds | 14 February 2018, 18:06:41 UTC | Merge tag 'powerpc-4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: "A larger batch of fixes than we'd like. Roughly 1/3 fixes for new code, 1/3 fixes for stable and 1/3 minor things. There's four commits fixing bugs when using 16GB huge pages on hash, caused by some of the preparatory changes for pkeys. Two fixes for bugs in the enhanced IRQ soft masking for local_t, one of which broke KVM in some circumstances. Four fixes for Power9. The most bizarre being a bug where futexes stopped working because a NULL pointer dereference didn't trap during early boot (it aliased the kernel mapping). A fix for memory hotplug when using the Radix MMU, and a fix for live migration of guests using the Radix MMU. Two fixes for hotplug on pseries machines. One where we weren't correctly updating NUMA info when CPUs are added and removed. And the other fixes crashes/hangs seen when doing memory hot remove during boot, which is apparently a thing people do. Finally a handful of build fixes for obscure configs and other minor fixes. Thanks to: Alexey Kardashevskiy, Aneesh Kumar K.V, Balbir Singh, Colin Ian King, Daniel Henrique Barboza, Florian Weimer, Guenter Roeck, Harish, Laurent Vivier, Madhavan Srinivasan, Mauricio Faria de Oliveira, Nathan Fontenot, Nicholas Piggin, Sam Bobroff" * tag 'powerpc-4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: selftests/powerpc: Fix to use ucontext_t instead of struct ucontext powerpc/kdump: Fix powernv build break when KEXEC_CORE=n powerpc/pseries: Fix build break for SPLPAR=n and CPU hotplug powerpc/mm/hash64: Zero PGD pages on allocation powerpc/mm/hash64: Store the slot information at the right offset for hugetlb powerpc/mm/hash64: Allocate larger PMD table if hugetlb config is enabled powerpc/mm: Fix crashes with 16G huge pages powerpc/mm: Flush radix process translations when setting MMU type powerpc/vas: Don't set uses_vas for kernel windows powerpc/pseries: Enable RAS hotplug events later powerpc/mm/radix: Split linear mapping on hot-unplug powerpc/64s/radix: Boot-time NULL pointer protection using a guard-PID ocxl: fix signed comparison with less than zero powerpc/64s: Fix may_hard_irq_enable() for PMI soft masking powerpc/64s: Fix MASKABLE_RELON_EXCEPTION_HV_OOL macro powerpc/numa: Invalidate numa_cpu_lookup_table on cpu remove | 14 February 2018, 18:06:41 UTC |
| 49edd5b | Andreas Gruenbacher | 06 February 2018, 14:20:55 UTC | gfs2: Fixes to "Implement iomap for block_map" It turns out that commit 3974320ca6 "Implement iomap for block_map" introduced a few bugs that trigger occasional failures with xfstest generic/476: In gfs2_iomap_begin, we jump to do_alloc when we determine that we are beyond the end of the allocated metadata (height > ip->i_height). There, we can end up calling hole_size with a metapath that doesn't match the current metadata tree, which doesn't make sense. After untangling the code at do_alloc, fix this by checking if the block we are looking for is within the range of allocated metadata. In addition, add a BUG() in case gfs2_iomap_begin is accidentally called for reading stuffed files: this is handled separately. Make sure we don't truncate iomap->length for reads beyond the end of the file; in that case, the entire range counts as a hole. Finally, revert to taking a bitmap write lock when doing allocations. It's unclear why that change didn't lead to any failures during testing. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Bob Peterson <rpeterso@redhat.com> | 13 February 2018, 20:38:10 UTC |
| 61f14c0 | Linus Torvalds | 13 February 2018, 17:35:17 UTC | Merge tag 'mips_4.16_2' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips Pull MIPS fix from James Hogan: "A single change (and associated DT binding update) to allow the address of the MIPS Cluster Power Controller (CPC) to be chosen by DT, which allows SMP to work on generic MIPS kernels where the bootloader hasn't configured the CPC address (i.e. the new Ranchu platform)" * tag 'mips_4.16_2' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips: MIPS: CPC: Map registers using DT in mips_cpc_default_phys_base() dt-bindings: Document mti,mips-cpc binding | 13 February 2018, 17:35:17 UTC |
| ecdf06e | Harish | 13 February 2018, 06:32:55 UTC | selftests/powerpc: Fix to use ucontext_t instead of struct ucontext With glibc 2.26 'struct ucontext' is removed to improve POSIX compliance, which breaks powerpc/alignment_handler selftest. Fix the test by using ucontext_t. Tested on ppc, works with older glibc versions as well. Fixes the following: alignment_handler.c: In function ‘sighandler’: alignment_handler.c:68:5: error: dereferencing pointer to incomplete type ‘struct ucontext’ ucp->uc_mcontext.gp_regs[PT_NIP] += 4; Signed-off-by: Harish <harish@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> | 13 February 2018, 11:44:18 UTC |
| 9109617 | Guenter Roeck | 12 February 2018, 22:34:07 UTC | powerpc/kdump: Fix powernv build break when KEXEC_CORE=n If KEXEC_CORE is not enabled, powernv builds fail as follows. arch/powerpc/platforms/powernv/smp.c: In function 'pnv_smp_cpu_kill_self': arch/powerpc/platforms/powernv/smp.c:236:4: error: implicit declaration of function 'crash_ipi_callback' Add dummy function calls, similar to kdump_in_progress(), to solve the problem. Fixes: 4145f358644b ("powernv/kdump: Fix cases where the kdump kernel can get HMI's") Signed-off-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> | 13 February 2018, 11:39:37 UTC |
| 8234348 | Guenter Roeck | 12 February 2018, 22:34:08 UTC | powerpc/pseries: Fix build break for SPLPAR=n and CPU hotplug Commit e67e02a544e9 ("powerpc/pseries: Fix cpu hotplug crash with memoryless nodes") adds an unconditional call to find_and_online_cpu_nid(), which is only declared if CONFIG_PPC_SPLPAR is enabled. This results in the following build error if this is not the case. arch/powerpc/platforms/pseries/hotplug-cpu.o: In function `dlpar_online_cpu': arch/powerpc/platforms/pseries/hotplug-cpu.c:369: undefined reference to `.find_and_online_cpu_nid' Follow the guideline provided by similar functions and provide a dummy function if CONFIG_PPC_SPLPAR is not enabled. This also moves the external function declaration into an include file where it should be. Fixes: e67e02a544e9 ("powerpc/pseries: Fix cpu hotplug crash with memoryless nodes") Signed-off-by: Guenter Roeck <linux@roeck-us.net> [mpe: Change subject to emphasise the build fix] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> | 13 February 2018, 11:38:39 UTC |
| fc5c2f4 | Aneesh Kumar K.V | 13 February 2018, 11:09:33 UTC | powerpc/mm/hash64: Zero PGD pages on allocation On powerpc we allocate page table pages from slab caches of different sizes. Currently we have a constructor that zeroes out the objects when we allocate them for the first time. We expect the objects to be zeroed out when we free the the object back to slab cache. This happens in the unmap path. For hugetlb pages we call huge_pte_get_and_clear() to do that. With the current configuration of page table size, both PUD and PGD level tables are allocated from the same slab cache. At the PUD level, we use the second half of the table to store the slot information. But we never clear that when unmapping. When such a freed object is then allocated for a PGD page, the second half of the page table page will not be zeroed as expected. This results in a kernel crash. Fix it by always clearing PGD pages when they're allocated. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> [mpe: Change log wording and formatting, add whitespace] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> | 13 February 2018, 11:37:48 UTC |
| ff31e10 | Aneesh Kumar K.V | 11 February 2018, 15:00:08 UTC | powerpc/mm/hash64: Store the slot information at the right offset for hugetlb The hugetlb pte entries are at the PMD and PUD level, so we can't use PTRS_PER_PTE to find the second half of the page table. Use the right offset for PUD/PMD to get to the second half of the table. Fixes: bf9a95f9a648 ("powerpc: Free up four 64K PTE bits in 64K backed HPTE pages") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> | 13 February 2018, 11:37:48 UTC |
| 4a7aa4f | Aneesh Kumar K.V | 11 February 2018, 15:00:07 UTC | powerpc/mm/hash64: Allocate larger PMD table if hugetlb config is enabled We use the second half of the page table to store slot information, so we must allocate it always if hugetlb is possible. Fixes: bf9a95f9a648 ("powerpc: Free up four 64K PTE bits in 64K backed HPTE pages") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> | 13 February 2018, 11:37:48 UTC |
| fae2211 | Aneesh Kumar K.V | 11 February 2018, 15:00:06 UTC | powerpc/mm: Fix crashes with 16G huge pages To support memory keys, we moved the hash pte slot information to the second half of the page table. This was ok with PTE entries at level 4 (PTE page) and level 3 (PMD). We already allocate larger page table pages at those levels to accomodate extra details. For level 4 we already have the extra space which was used to track 4k hash page table entry details and at level 3 the extra space was allocated to track the THP details. With hugetlbfs PTE, we used this extra space at the PMD level to store the slot details. But we also support hugetlbfs PTE at PUD level for 16GB pages and PUD level page didn't allocate extra space. This resulted in memory corruption. Fix this by allocating extra space at PUD level when HUGETLB is enabled. Fixes: bf9a95f9a648 ("powerpc: Free up four 64K PTE bits in 64K backed HPTE pages") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> | 13 February 2018, 11:37:47 UTC |
| 62e984d | Alexey Kardashevskiy | 01 February 2018, 05:09:44 UTC | powerpc/mm: Flush radix process translations when setting MMU type Radix guests do normally invalidate process-scoped translations when a new pid is allocated but migrated guests do not invalidate these so migrated guests crash sometime, especially easy to reproduce with migration happening within first 10 seconds after the guest boot start on the same machine. This adds the "Invalidate process-scoped translations" flush to fix radix guests migration. Fixes: 2ee13be34b13 ("KVM: PPC: Book3S HV: Update kvmppc_set_arch_compat() for ISA v3.00") Cc: stable@vger.kernel.org # v4.10+ Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Tested-by: Laurent Vivier <lvivier@redhat.com> Tested-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> | 13 February 2018, 11:37:47 UTC |
| b00b628 | Nicholas Piggin | 08 February 2018, 09:18:38 UTC | powerpc/vas: Don't set uses_vas for kernel windows cp_abort is only required for user windows, because kernel context must not be preempted between a copy/paste pair. Without this patch, the init task gets used_vas set when it runs the nx842_powernv_init initcall, which opens windows for kernel usage. used_vas is then never cleared anywhere, so it gets propagated into all other tasks. It's a property of the address space, so it should really be cleared when a new mm is created (or in dup_mmap if the mmaps are marked as VM_DONTCOPY). For now we seem to have no such driver, so leave that for another patch. Fixes: 6c8e6bb2a52d ("powerpc/vas: Add support for user receive window") Cc: stable@vger.kernel.org # v4.15+ Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> | 13 February 2018, 11:37:46 UTC |
| c9dccf1 | Sam Bobroff | 12 February 2018, 00:19:29 UTC | powerpc/pseries: Enable RAS hotplug events later Currently if the kernel receives a memory hot-unplug event early enough, it may get stuck in an infinite loop in dissolve_free_huge_pages(). This appears as a stall just after: pseries-hotplug-mem: Attempting to hot-remove XX LMB(s) at YYYYYYYY It appears to be caused by "minimum_order" being uninitialized, due to init_ras_IRQ() executing before hugetlb_init(). To correct this, extract the part of init_ras_IRQ() that enables hotplug event processing and place it in the machine_late_initcall phase, which is guaranteed to be after hugetlb_init() is called. Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> [mpe: Reorder the functions to make the diff readable] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> | 13 February 2018, 11:37:46 UTC |
| 2cbc0d6 | Dominik Brodowski | 11 February 2018, 11:10:11 UTC | selftests/x86: Do not rely on "int $0x80" in test_mremap_vdso.c On 64-bit builds, we should not rely on "int $0x80" working (it only does if CONFIG_IA32_EMULATION=y is enabled). Without this patch, the move test may succeed, but the "int $0x80" causes a segfault, resulting in a false negative output of this self-test. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dmitry Safonov <dsafonov@virtuozzo.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kselftest@vger.kernel.org Cc: shuah@kernel.org Link: http://lkml.kernel.org/r/20180211111013.16888-4-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:05:37 UTC |
| 7f95122 | Dominik Brodowski | 11 February 2018, 11:10:09 UTC | selftests/x86: Fix build bug caused by the 5lvl test which has been moved to the VM directory Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kselftest@vger.kernel.org Cc: shuah@kernel.org Fixes: 235266b8e11c "selftests/vm: move 128TB mmap boundary test to generic directory" Link: http://lkml.kernel.org/r/20180211111013.16888-2-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:05:32 UTC |
| ce67663 | Ingo Molnar | 13 February 2018, 07:26:17 UTC | selftests/x86/pkeys: Remove unused functions This also gets rid of two build warnings: protection_keys.c: In function ‘dumpit’: protection_keys.c:419:3: warning: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Wunused-result] write(1, buf, nr_read); ^~~~~~~~~~~~~~~~~~~~~~ Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Shuah Khan <shuahkh@osg.samsung.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:56 UTC |
| d8e92de | Dominik Brodowski | 11 February 2018, 20:59:24 UTC | selftests/x86: Clean up and document sscanf() usage Replace a couple of magically connected buffer length literal constants with a common definition that makes their relationship obvious. Also document why our sscanf() usage is safe. No intended functional changes. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andrew Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kselftest@vger.kernel.org Cc: shuah@kernel.org Link: http://lkml.kernel.org/r/20180211205924.GA23210@light.dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:56 UTC |
| 198ee8e | Dominik Brodowski | 11 February 2018, 11:10:10 UTC | selftests/x86: Fix vDSO selftest segfault for vsyscall=none The vDSO selftest tries to execute a vsyscall unconditionally, even if it is not present on the test system (e.g. if booted with vsyscall=none or with CONFIG_LEGACY_VSYSCALL_NONE=y set. Fix this by copying (and tweaking) the vsyscall check from test_vsyscall.c Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andrew Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kselftest@vger.kernel.org Cc: shuah@kernel.org Link: http://lkml.kernel.org/r/20180211111013.16888-3-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:55 UTC |
| b498c26 | Borislav Petkov | 12 February 2018, 20:13:18 UTC | x86/entry/64: Remove the unused 'icebp' macro That macro was touched around 2.5.8 times, judging by the full history linux repo, but it was unused even then. Get rid of it already. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux@dominikbrodowski.net Link: http://lkml.kernel.org/r/20180212201318.GD14640@pd.tnic Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:55 UTC |
| b3ccefa | Josh Poimboeuf | 12 February 2018, 17:45:03 UTC | x86/entry/64: Fix paranoid_entry() frame pointer warning With the following commit: f09d160992d1 ("x86/entry/64: Get rid of the ALLOC_PT_GPREGS_ON_STACK and SAVE_AND_CLEAR_REGS macros") ... one of my suggested improvements triggered a frame pointer warning: arch/x86/entry/entry_64.o: warning: objtool: paranoid_entry()+0x11: call without frame pointer save/setup The warning is correct for the build-time code, but it's actually not relevant at runtime because of paravirt patching. The paravirt swapgs call gets replaced with either a SWAPGS instruction or NOPs at runtime. Go back to the previous behavior by removing the ELF function annotation for paranoid_entry() and adding an unwind hint, which effectively silences the warning. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kbuild-all@01.org Cc: tipbuild@zytor.com Fixes: f09d160992d1 ("x86/entry/64: Get rid of the ALLOC_PT_GPREGS_ON_STACK and SAVE_AND_CLEAR_REGS macros") Link: http://lkml.kernel.org/r/20180212174503.5acbymg5z6p32snu@treble Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:55 UTC |
| 92816f5 | Dominik Brodowski | 11 February 2018, 10:49:48 UTC | x86/entry/64: Indent PUSH_AND_CLEAR_REGS and POP_REGS properly ... same as the other macros in arch/x86/entry/calling.h Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180211104949.12992-8-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:54 UTC |
| dde3036 | Dominik Brodowski | 11 February 2018, 10:49:47 UTC | x86/entry/64: Get rid of the ALLOC_PT_GPREGS_ON_STACK and SAVE_AND_CLEAR_REGS macros Previously, error_entry() and paranoid_entry() saved the GP registers onto stack space previously allocated by its callers. Combine these two steps in the callers, and use the generic PUSH_AND_CLEAR_REGS macro for that. This adds a significant amount ot text size. However, Ingo Molnar points out that: "these numbers also _very_ significantly over-represent the extra footprint. The assumptions that resulted in us compressing the IRQ entry code have changed very significantly with the new x86 IRQ allocation code we introduced in the last year: - IRQ vectors are usually populated in tightly clustered groups. With our new vector allocator code the typical per CPU allocation percentage on x86 systems is ~3 device vectors and ~10 fixed vectors out of ~220 vectors - i.e. a very low ~6% utilization (!). [...] The days where we allocated a lot of vectors on every CPU and the compression of the IRQ entry code text mattered are over. - Another issue is that only a small minority of vectors is frequent enough to actually matter to cache utilization in practice: 3-4 key IPIs and 1-2 device IRQs at most - and those vectors tend to be tightly clustered as well into about two groups, and are probably already on 2-3 cache lines in practice. For the common case of 'cache cold' IRQs it's the depth of the call chain and the fragmentation of the resulting I$ that should be the main performance limit - not the overall size of it. - The CPU side cost of IRQ delivery is still very expensive even in the best, most cached case, as in 'over a thousand cycles'. So much stuff is done that maybe contemporary x86 IRQ entry microcode already prefetches the IDT entry and its expected call target address."[*] [*] http://lkml.kernel.org/r/20180208094710.qnjixhm6hybebdv7@gmail.com The "testb $3, CS(%rsp)" instruction in the idtentry macro does not need modification. Previously, %rsp was manually decreased by 15*8; with this patch, %rsp is decreased by 15 pushq instructions. [jpoimboe@redhat.com: unwind hint improvements] Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180211104949.12992-7-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:54 UTC |
| 30907fd | Dominik Brodowski | 11 February 2018, 10:49:46 UTC | x86/entry/64: Use PUSH_AND_CLEAN_REGS in more cases entry_SYSCALL_64_after_hwframe() and nmi() can be converted to use PUSH_AND_CLEAN_REGS instead of opencoded variants thereof. Due to the interleaving, the additional XOR-based clearing of R8 and R9 in entry_SYSCALL_64_after_hwframe() should not have any noticeable negative implications. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180211104949.12992-6-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:53 UTC |
| 3f01dae | Dominik Brodowski | 11 February 2018, 10:49:45 UTC | x86/entry/64: Introduce the PUSH_AND_CLEAN_REGS macro Those instances where ALLOC_PT_GPREGS_ON_STACK is called just before SAVE_AND_CLEAR_REGS can trivially be replaced by PUSH_AND_CLEAN_REGS. This macro uses PUSH instead of MOV and should therefore be faster, at least on newer CPUs. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180211104949.12992-5-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:53 UTC |
| f7bafa2 | Dominik Brodowski | 11 February 2018, 10:49:44 UTC | x86/entry/64: Interleave XOR register clearing with PUSH instructions Same as is done for syscalls, interleave XOR with PUSH instructions for exceptions/interrupts, in order to minimize the cost of the additional instructions required for register clearing. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180211104949.12992-4-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:53 UTC |
| 502af0d | Dominik Brodowski | 11 February 2018, 10:49:43 UTC | x86/entry/64: Merge the POP_C_REGS and POP_EXTRA_REGS macros into a single POP_REGS macro The two special, opencoded cases for POP_C_REGS can be handled by ASM macros. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180211104949.12992-3-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:52 UTC |
| 2e3f009 | Dominik Brodowski | 11 February 2018, 10:49:42 UTC | x86/entry/64: Merge SAVE_C_REGS and SAVE_EXTRA_REGS, remove unused extensions All current code paths call SAVE_C_REGS and then immediately SAVE_EXTRA_REGS. Therefore, merge these two macros and order the MOV sequeneces properly. While at it, remove the macros to save all except specific registers, as these macros have been unused for a long time. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180211104949.12992-2-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org> | 13 February 2018, 08:04:52 UTC |
