diff options
author | bibo mao <bibo.mao@intel.com> | 2006-07-28 14:44:48 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-07-28 19:28:00 -0700 |
commit | a4045dff782a8692637c24a0222120082c887caa (patch) | |
tree | 67f4fe2bb6975bce2887c295752c7612896130f9 | |
parent | 0e92da4acb763272c6060f0b14adc2377b627d07 (diff) |
[PATCH] x86_64: Enlarge debug stack for nested kprobes
In x86_64 platform, INT1 and INT3 trap stack is IST stack called DEBUG_STACK,
when INT1/INT3 trap happens, system will switch to DEBUG_STACK by hardware.
Current DEBUG_STACK size is 4K, when int1/int3 trap happens, kernel will
minus current DEBUG_STACK IST value by 4k. But if int3/int1 trap is nested,
it will destroy other vector's IST stack. This patch modifies this, it sets
DEBUG_STACK size as 8K and allows two level of nested int1/int3 trap.
Kprobe DEBUG_STACK may be nested, because kprobe handler may be probed
by other kprobes.
Thanks jbeulich for pointing out error in the first patch.
[AK: nested kprobes are pretty dubious. Hopefully one nest
will be enough. This will cost 8K per CPU (4K more than before)]
Signed-off-by: bibo, mao <bibo.mao@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r-- | include/asm-x86_64/page.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/asm-x86_64/page.h b/include/asm-x86_64/page.h index f7bf875aae4..10f346165ca 100644 --- a/include/asm-x86_64/page.h +++ b/include/asm-x86_64/page.h @@ -19,7 +19,7 @@ #define EXCEPTION_STACK_ORDER 0 #define EXCEPTION_STKSZ (PAGE_SIZE << EXCEPTION_STACK_ORDER) -#define DEBUG_STACK_ORDER EXCEPTION_STACK_ORDER +#define DEBUG_STACK_ORDER (EXCEPTION_STACK_ORDER + 1) #define DEBUG_STKSZ (PAGE_SIZE << DEBUG_STACK_ORDER) #define IRQSTACK_ORDER 2 |