Revision - 50b2d49 - KVM: x86: Inject #UD on emulated XSETBV if XSAVES isn't enabled - origin: https://github.com/torvalds/linux

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05 April 2024, 19:05:47 UTC

Revision 50b2d49bafa16e6311ab2da82f5aafc5f9ada99b authored by Sean Christopherson on 24 August 2022, 03:30:57 UTC, committed by Paolo Bonzini on 22 September 2022, 21:04:20 UTC

KVM: x86: Inject #UD on emulated XSETBV if XSAVES isn't enabled

Inject #UD when emulating XSETBV if CR4.OSXSAVE is not set.  This also
covers the "XSAVE not supported" check, as setting CR4.OSXSAVE=1 #GPs if
XSAVE is not supported (and userspace gets to keep the pieces if it
forces incoherent vCPU state).

Add a comment to kvm_emulate_xsetbv() to call out that the CPU checks
CR4.OSXSAVE before checking for intercepts.  AMD'S APM implies that #UD
has priority (says that intercepts are checked before #GP exceptions),
while Intel's SDM says nothing about interception priority.  However,
testing on hardware shows that both AMD and Intel CPUs prioritize the #UD
over interception.

Fixes: 02d4160fbd76 ("x86: KVM: add xsetbv to the emulator")
Cc: stable@vger.kernel.org
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220824033057.3576315-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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Tip revision: 50b2d49bafa16e6311ab2da82f5aafc5f9ada99b authored by Sean Christopherson on 24 August 2022, 03:30:57 UTC
KVM: x86: Inject #UD on emulated XSETBV if XSAVES isn't enabled

Tip revision: 50b2d49

File	Mode	Size
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arch
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certs
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drivers
fs
include
init
io_uring
ipc
kernel
lib
mm
net
samples
scripts
security
sound
tools
usr
virt
.clang-format	-rw-r--r--	19.9 KB
.cocciconfig	-rw-r--r--	59 bytes
.get_maintainer.ignore	-rw-r--r--	151 bytes
.gitattributes	-rw-r--r--	62 bytes
.gitignore	-rw-r--r--	1.9 KB
.mailmap	-rw-r--r--	23.7 KB
COPYING	-rw-r--r--	496 bytes
CREDITS	-rw-r--r--	99.1 KB
Kbuild	-rw-r--r--	1.3 KB
Kconfig	-rw-r--r--	555 bytes
MAINTAINERS	-rw-r--r--	663.6 KB
Makefile	-rw-r--r--	64.5 KB
README	-rw-r--r--	727 bytes

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KVM: x86: Inject #UD on emulated XSETBV if XSAVES isn't enabled

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