aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2007-12-20 19:27:19 -0500
committerIngo Molnar <mingo@elte.hu>2007-12-20 19:27:19 -0500
commitc0a698b7443a9fce76b0a849f06c45ac78f3b0a0 (patch)
treece528f832d075920f1030206a1fd016d7bf215eb /arch/x86/kernel
parentfaa4877f023bafa35239d411b160955dc0629fe9 (diff)
x86: fix die() to not be preemptible
Andrew "Eagle Eye" Morton noticed that we use raw_local_save_flags() instead of raw_local_irq_save(flags) in die(). This allows the preemption of oopsing contexts - which is highly undesirable. It also causes CONFIG_DEBUG_PREEMPT to complain, as reported by Miles Lane. this bug was introduced via: commit 39743c9ef717fd4f2b5583f010115c5f2482b8ae Author: Andi Kleen <ak@suse.de> Date: Fri Oct 19 20:35:03 2007 +0200 x86: use raw locks during oopses - spin_lock_irqsave(&die.lock, flags); + __raw_spin_lock(&die.lock); + raw_local_save_flags(flags); that is not a correct open-coding of spin_lock_irqsave(): both the ordering is wrong (irqs should be disabled _first_), and the wrong flags-saving API was used. Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r--arch/x86/kernel/traps_32.c7
1 files changed, 3 insertions, 4 deletions
diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c
index ef6010262597..c88bbffcaa03 100644
--- a/arch/x86/kernel/traps_32.c
+++ b/arch/x86/kernel/traps_32.c
@@ -373,14 +373,13 @@ void die(const char * str, struct pt_regs * regs, long err)
373 373
374 if (die.lock_owner != raw_smp_processor_id()) { 374 if (die.lock_owner != raw_smp_processor_id()) {
375 console_verbose(); 375 console_verbose();
376 raw_local_irq_save(flags);
376 __raw_spin_lock(&die.lock); 377 __raw_spin_lock(&die.lock);
377 raw_local_save_flags(flags);
378 die.lock_owner = smp_processor_id(); 378 die.lock_owner = smp_processor_id();
379 die.lock_owner_depth = 0; 379 die.lock_owner_depth = 0;
380 bust_spinlocks(1); 380 bust_spinlocks(1);
381 } 381 } else
382 else 382 raw_local_irq_save(flags);
383 raw_local_save_flags(flags);
384 383
385 if (++die.lock_owner_depth < 3) { 384 if (++die.lock_owner_depth < 3) {
386 unsigned long esp; 385 unsigned long esp;