Revision 3cb5f1a3e58c0bd70d47d9907cc5c65192281dee authored by Steven Rostedt on 23 December 2010, 19:46:06 UTC, committed by Benjamin Herrenschmidt on 21 January 2011, 03:08:33 UTC
When an interrupt occurs in userspace, we can call trace_hardirqs_on/off() With one level stack. But if we have irqsoff tracing enabled, it checks both CALLER_ADDR0 and CALLER_ADDR1. The second call goes two stack frames up. If this is from user space, then there may not exist a second stack. Add a second stack when calling trace_hardirqs_on/off() otherwise the following oops might occur: Oops: Kernel access of bad area, sig: 11 [#1] PREEMPT SMP NR_CPUS=2 PA Semi PWRficient last sysfs file: /sys/block/sda/size Modules linked in: ohci_hcd ehci_hcd usbcore NIP: c0000000000e1c00 LR: c0000000000034d4 CTR: 000000011012c440 REGS: c00000003e2f3af0 TRAP: 0300 Not tainted (2.6.37-rc6+) MSR: 9000000000001032 <ME,IR,DR> CR: 48044444 XER: 20000000 DAR: 00000001ffb9db50, DSISR: 0000000040000000 TASK = c00000003e1a00a0[2088] 'emacs' THREAD: c00000003e2f0000 CPU: 1 GPR00: 0000000000000001 c00000003e2f3d70 c00000000084e0d0 c0000000008816e8 GPR04: 000000001034c678 000000001032e8f9 0000000010336540 0000000040020000 GPR08: 0000000040020000 00000001ffb9db40 c00000003e2f3e30 0000000060000000 GPR12: 100000000000f032 c00000000fff0280 000000001032e8c9 0000000000000008 GPR16: 00000000105be9c0 00000000105be950 00000000105be9b0 00000000105be950 GPR20: 00000000ffb9dc50 00000000ffb9dbf0 00000000102f0000 00000000102f0000 GPR24: 00000000102e0000 00000000102f0000 0000000010336540 c0000000009ded38 GPR28: 00000000102e0000 c0000000000034d4 c0000000007ccb10 c00000003e2f3d70 NIP [c0000000000e1c00] .trace_hardirqs_off+0xb0/0x1d0 LR [c0000000000034d4] decrementer_common+0xd4/0x100 Call Trace: [c00000003e2f3d70] [c00000003e2f3e30] 0xc00000003e2f3e30 (unreliable) [c00000003e2f3e30] [c0000000000034d4] decrementer_common+0xd4/0x100 Instruction dump: 81690000 7f8b0000 419e0018 f84a0028 60000000 60000000 60000000 e95f0000 80030000 e92a0000 eb6301f8 2f800000 <eb890010> 41fe00dc a06d000a eb1e8050 ---[ end trace 4ec7fd2be9240928 ]--- Reported-by: Joerg Sommer <joerg@alea.gnuu.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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File | Mode | Size |
---|---|---|
Makefile | -rw-r--r-- | 394 bytes |
compat.c | -rw-r--r-- | 17.0 KB |
compat_mq.c | -rw-r--r-- | 4.1 KB |
ipc_sysctl.c | -rw-r--r-- | 5.1 KB |
ipcns_notifier.c | -rw-r--r-- | 2.2 KB |
mq_sysctl.c | -rw-r--r-- | 2.7 KB |
mqueue.c | -rw-r--r-- | 30.5 KB |
msg.c | -rw-r--r-- | 20.8 KB |
msgutil.c | -rw-r--r-- | 2.8 KB |
namespace.c | -rw-r--r-- | 3.3 KB |
sem.c | -rw-r--r-- | 40.3 KB |
shm.c | -rw-r--r-- | 26.5 KB |
syscall.c | -rw-r--r-- | 2.3 KB |
util.c | -rw-r--r-- | 22.9 KB |
util.h | -rw-r--r-- | 5.2 KB |
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