diff options
| author | Corey Minyard <minyard@acm.org> | 2006-05-08 15:17:22 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-05-08 09:34:56 -0700 |
| commit | cdc60a4c8e71c4bcf67e83fac6c0cabd0ff19bfe (patch) | |
| tree | 204e3ab2ccaa9828d0ea71b43891729b216db7bf /arch/x86_64 | |
| parent | 5192d84e4c32cd335fd572e5ff0712041f45f7e7 (diff) | |
| download | linux-cdc60a4c8e71c4bcf67e83fac6c0cabd0ff19bfe.tar.gz | |
[PATCH] x86_64: fix die_lock nesting
I noticed this when poking around in this area. The oops_begin() function in x86_64 would only conditionally claim the die_lock if the call is nested, but oops_end() would always release the spinlock. This patch adds a nest count for the die lock so that the release of the lock is only done on the final oops_end(). Signed-off-by: Corey Minyard <minyard@acm.org> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/x86_64')
| -rw-r--r-- | arch/x86_64/kernel/traps.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c index 2700b1375c1f..0ebb281aa178 100644 --- a/arch/x86_64/kernel/traps.c +++ b/arch/x86_64/kernel/traps.c @@ -385,6 +385,7 @@ void out_of_line_bug(void) static DEFINE_SPINLOCK(die_lock); static int die_owner = -1; +static unsigned int die_nest_count; unsigned __kprobes long oops_begin(void) { @@ -399,6 +400,7 @@ unsigned __kprobes long oops_begin(void) else spin_lock(&die_lock); } + die_nest_count++; die_owner = cpu; console_verbose(); bust_spinlocks(1); @@ -409,7 +411,13 @@ void __kprobes oops_end(unsigned long flags) { die_owner = -1; bust_spinlocks(0); - spin_unlock_irqrestore(&die_lock, flags); + die_nest_count--; + if (die_nest_count) + /* We still own the lock */ + local_irq_restore(flags); + else + /* Nest count reaches zero, release the lock. */ + spin_unlock_irqrestore(&die_lock, flags); if (panic_on_oops) panic("Oops"); } |