2009-10-17 09:58:37

by Masami Hiramatsu

[permalink] [raw]
Subject: [tip:perf/probes] kprobes: Prohibit to probe native_get_debugreg

Commit-ID: 65e234ec2c4a0659ca22531dc1372a185f088517
Gitweb: http://git.kernel.org/tip/65e234ec2c4a0659ca22531dc1372a185f088517
Author: Masami Hiramatsu <[email protected]>
AuthorDate: Thu, 27 Aug 2009 13:23:32 -0400
Committer: Frederic Weisbecker <[email protected]>
CommitDate: Sun, 30 Aug 2009 03:15:55 +0200

kprobes: Prohibit to probe native_get_debugreg

Since do_debug() calls get_debugreg(), native_get_debugreg() will be
called from singlestepping. This can cause an int3 infinite loop.

We can't put it in the .text.kprobes section because it is inlined,
then we blacklist its name.

Signed-off-by: Masami Hiramatsu <[email protected]>
Acked-by: Ananth N Mavinakayanahalli <[email protected]>
Cc: Ingo Molnar <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Frederic Weisbecker <[email protected]>
---
kernel/kprobes.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index f72e96c..3267d90 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -90,6 +90,7 @@ static spinlock_t *kretprobe_table_lock_ptr(unsigned long hash)
*/
static struct kprobe_blackpoint kprobe_blacklist[] = {
{"preempt_schedule",},
+ {"native_get_debugreg",},
{NULL} /* Terminator */
};