[PATCH] kprobes: fix bug when probed on task and isr functions
This patch fixes a race condition where in system used to hang or sometime
crash within minutes when kprobes are inserted on ISR routine and a task
routine.
The fix has been stress tested on i386, ia64, pp64 and on x86_64. To
reproduce the problem insert kprobes on schedule() and do_IRQ() functions
and you should see hang or system crash.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/x86_64/kernel/kprobes.c b/arch/x86_64/kernel/kprobes.c
index 2d7658f..df08c43 100644
--- a/arch/x86_64/kernel/kprobes.c
+++ b/arch/x86_64/kernel/kprobes.c
@@ -311,7 +311,8 @@
Disarm the probe we just hit, and ignore it. */
p = get_kprobe(addr);
if (p) {
- if (kprobe_status == KPROBE_HIT_SS) {
+ if (kprobe_status == KPROBE_HIT_SS &&
+ *p->ainsn.insn == BREAKPOINT_INSTRUCTION) {
regs->eflags &= ~TF_MASK;
regs->eflags |= kprobe_saved_rflags;
unlock_kprobes();