Don't want any lockdep or other fragile machinery to run during oopses.
Use raw spinlocks directly for oops locking.
Also disables irq flag tracing there.
Signed-off-by: Andi Kleen <ak@suse.de>
---
arch/i386/kernel/traps.c | 12 +++++++-----
arch/x86_64/kernel/traps.c | 17 ++++++++---------
2 files changed, 15 insertions(+), 14 deletions(-)
Index: linux/arch/i386/kernel/traps.c
===================================================================
--- linux.orig/arch/i386/kernel/traps.c
+++ linux/arch/i386/kernel/traps.c
@@ -447,11 +447,11 @@ void ler_enable(void) {
void die(const char * str, struct pt_regs * regs, long err)
{
static struct {
- spinlock_t lock;
+ raw_spinlock_t lock;
u32 lock_owner;
int lock_owner_depth;
} die = {
- .lock = __SPIN_LOCK_UNLOCKED(die.lock),
+ .lock = __RAW_SPIN_LOCK_UNLOCKED,
.lock_owner = -1,
.lock_owner_depth = 0
};
@@ -462,13 +462,14 @@ void die(const char * str, struct pt_reg
if (die.lock_owner != raw_smp_processor_id()) {
console_verbose();
- spin_lock_irqsave(&die.lock, flags);
+ __raw_spin_lock(&die.lock);
+ raw_local_save_flags(flags);
die.lock_owner = smp_processor_id();
die.lock_owner_depth = 0;
bust_spinlocks(1);
}
else
- local_save_flags(flags);
+ raw_local_save_flags(flags);
if (++die.lock_owner_depth < 3) {
unsigned long esp;
@@ -511,7 +512,8 @@ void die(const char * str, struct pt_reg
bust_spinlocks(0);
die.lock_owner = -1;
add_taint(TAINT_DIE);
- spin_unlock_irqrestore(&die.lock, flags);
+ __raw_spin_unlock(&die.lock);
+ raw_local_irq_restore(flags);
if (!regs)
return;
Index: linux/arch/x86_64/kernel/traps.c
===================================================================
--- linux.orig/arch/x86_64/kernel/traps.c
+++ linux/arch/x86_64/kernel/traps.c
@@ -556,7 +556,7 @@ void ler_enable(void) {
}
}
-static DEFINE_SPINLOCK(die_lock);
+static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED;
static int die_owner = -1;
static unsigned int die_nest_count;
@@ -568,13 +568,13 @@ unsigned __kprobes long oops_begin(void)
oops_enter();
/* racy, but better than risking deadlock. */
- local_irq_save(flags);
+ raw_local_irq_save(flags);
cpu = smp_processor_id();
- if (!spin_trylock(&die_lock)) {
+ if (!__raw_spin_trylock(&die_lock)) {
if (cpu == die_owner)
/* nested oops. should stop eventually */;
else
- spin_lock(&die_lock);
+ __raw_spin_lock(&die_lock);
}
die_nest_count++;
die_owner = cpu;
@@ -588,12 +588,11 @@ void __kprobes oops_end(unsigned long fl
die_owner = -1;
bust_spinlocks(0);
die_nest_count--;
- if (die_nest_count)
- /* We still own the lock */
- local_irq_restore(flags);
- else
+ if (!die_nest_count) {
/* Nest count reaches zero, release the lock. */
- spin_unlock_irqrestore(&die_lock, flags);
+ __raw_spin_unlock(&die_lock);
+ }
+ raw_local_irq_restore(flags);
if (!regs) {
oops_exit();
return;
-
