diff options
| author | Andi Kleen <ak@suse.de> | 2006-05-15 18:19:47 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-05-16 07:59:32 -0700 |
| commit | 40e59a61669a3cab9e0bd24644e29155d6b00970 (patch) | |
| tree | 25db313781596303562a1a316592ffb9ff96542b /arch | |
| parent | fad7906d16e8c4926aeb5b0f1756eb9f55b2837d (diff) | |
| download | linux-40e59a61669a3cab9e0bd24644e29155d6b00970.tar.gz | |
[PATCH] x86_64: Don't schedule on exception stack on preemptive kernels
Extends an earlier patch from John Blackwood to more exception handlers
that also run on the exception stacks.
Expand the use of preempt_conditional_{sti,cli} to all cases where
interrupts are to be re-enabled during exception handling while running
on an IST stack.
Based on original patch from Jan Beulich.
Cc: John Blackwood <john.blackwood@ccur.com>
Cc: jbeulich@novell.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86_64/kernel/traps.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c index 6b87268c5c2e..cea335e8746c 100644 --- a/arch/x86_64/kernel/traps.c +++ b/arch/x86_64/kernel/traps.c @@ -102,6 +102,8 @@ static inline void preempt_conditional_cli(struct pt_regs *regs) { if (regs->eflags & X86_EFLAGS_IF) local_irq_disable(); + /* Make sure to not schedule here because we could be running + on an exception stack. */ preempt_enable_no_resched(); } @@ -483,8 +485,6 @@ static void __kprobes do_trap(int trapnr, int signr, char *str, { struct task_struct *tsk = current; - conditional_sti(regs); - tsk->thread.error_code = error_code; tsk->thread.trap_no = trapnr; @@ -521,6 +521,7 @@ asmlinkage void do_##name(struct pt_regs * regs, long error_code) \ if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ == NOTIFY_STOP) \ return; \ + conditional_sti(regs); \ do_trap(trapnr, signr, str, regs, error_code, NULL); \ } @@ -535,6 +536,7 @@ asmlinkage void do_##name(struct pt_regs * regs, long error_code) \ if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ == NOTIFY_STOP) \ return; \ + conditional_sti(regs); \ do_trap(trapnr, signr, str, regs, error_code, &info); \ } @@ -548,7 +550,17 @@ DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS) DO_ERROR(11, SIGBUS, "segment not present", segment_not_present) DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0) DO_ERROR(18, SIGSEGV, "reserved", reserved) -DO_ERROR(12, SIGBUS, "stack segment", stack_segment) + +/* Runs on IST stack */ +asmlinkage void do_stack_segment(struct pt_regs *regs, long error_code) +{ + if (notify_die(DIE_TRAP, "stack segment", regs, error_code, + 12, SIGBUS) == NOTIFY_STOP) + return; + preempt_conditional_sti(regs); + do_trap(12, SIGBUS, "stack segment", regs, error_code, NULL); + preempt_conditional_cli(regs); +} asmlinkage void do_double_fault(struct pt_regs * regs, long error_code) { @@ -682,8 +694,9 @@ asmlinkage void __kprobes do_int3(struct pt_regs * regs, long error_code) if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP) == NOTIFY_STOP) { return; } + preempt_conditional_sti(regs); do_trap(3, SIGTRAP, "int3", regs, error_code, NULL); - return; + preempt_conditional_cli(regs); } /* Help handler running on IST stack to switch back to user stack |