diff options
| author | Andy Lutomirski <luto@kernel.org> | 2020-06-12 06:26:38 +0300 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2020-06-12 13:12:57 +0300 |
| commit | 15a416e8aaa758b5534f64a3972dae05275bc225 (patch) | |
| tree | e4ae9ce3068dbd6df81a2a445be81e015a387aa5 /arch/x86/include | |
| parent | f0178fc01fe46bab6a95415f5647d1a74efcad1b (diff) | |
| download | linux-15a416e8aaa758b5534f64a3972dae05275bc225.tar.xz | |
x86/entry: Treat BUG/WARN as NMI-like entries
BUG/WARN are cleverly optimized using UD2 to handle the BUG/WARN out of
line in an exception fixup.
But if BUG or WARN is issued in a funny RCU context, then the
idtentry_enter...() path might helpfully WARN that the RCU context is
invalid, which results in infinite recursion.
Split the BUG/WARN handling into an nmi_enter()/nmi_exit() path in
exc_invalid_op() to increase the chance to survive the experience.
[ tglx: Make the declaration match the implementation ]
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/f8fe40e0088749734b4435b554f73eee53dcf7a8.1591932307.git.luto@kernel.org
Diffstat (limited to 'arch/x86/include')
| -rw-r--r-- | arch/x86/include/asm/idtentry.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index d203c541a65a..2fc6b0c58341 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -543,7 +543,6 @@ SYM_CODE_END(spurious_entries_start) DECLARE_IDTENTRY(X86_TRAP_DE, exc_divide_error); DECLARE_IDTENTRY(X86_TRAP_OF, exc_overflow); DECLARE_IDTENTRY(X86_TRAP_BR, exc_bounds); -DECLARE_IDTENTRY(X86_TRAP_UD, exc_invalid_op); DECLARE_IDTENTRY(X86_TRAP_NM, exc_device_not_available); DECLARE_IDTENTRY(X86_TRAP_OLD_MF, exc_coproc_segment_overrun); DECLARE_IDTENTRY(X86_TRAP_SPURIOUS, exc_spurious_interrupt_bug); @@ -561,6 +560,7 @@ DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_GP, exc_general_protection); DECLARE_IDTENTRY_ERRORCODE(X86_TRAP_AC, exc_alignment_check); /* Raw exception entries which need extra work */ +DECLARE_IDTENTRY_RAW(X86_TRAP_UD, exc_invalid_op); DECLARE_IDTENTRY_RAW(X86_TRAP_BP, exc_int3); DECLARE_IDTENTRY_RAW_ERRORCODE(X86_TRAP_PF, exc_page_fault); |