kprobes: Update document about irq disabled state in kprobe handler

Update kprobes.txt about interrupts disabled state inside
kprobes handlers, because optimized probe/boosted kretprobe
run without disabling interrrupts on x86.

Signed-off-by: Masami Hiramatsu <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Ananth N Mavinakayanahalli <[email protected]>
Cc: [email protected]
LKML-Reference: <20101014031018[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt
index 1762b81fcdf2ec4a235423687865453a16196aed..741fe66d6eca4852894cac79d6ad2d3162486c7a 100644 (file)
--- a/Documentation/kprobes.txt
+++ b/Documentation/kprobes.txt
@@ -542,9 +542,11 @@ Kprobes does not use mutexes or allocate memory except during
 registration and unregistration.
 
 Probe handlers are run with preemption disabled.  Depending on the
-architecture, handlers may also run with interrupts disabled.  In any
-case, your handler should not yield the CPU (e.g., by attempting to
-acquire a semaphore).
+architecture and optimization state, handlers may also run with
+interrupts disabled (e.g., kretprobe handlers and optimized kprobe
+handlers run without interrupt disabled on x86/x86-64).  In any case,
+your handler should not yield the CPU (e.g., by attempting to acquire
+a semaphore).
 
 Since a return probe is implemented by replacing the return
 address with the trampoline's address, stack backtraces and calls