From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
To: Ingo Molnar <mingo@kernel.org>
Cc: tixy@linaro.org, Wang Nan <wangnan0@huawei.com>,
linux@arm.linux.org.uk,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
lizefan@huawei.com, linux-arm-kernel@lists.infradead.org
Subject: [PATCH -tip/urgent 1/2] [BUGFIX]kprobes: set kprobes_all_disarmed earlier to enable re-optimization.
Date: Fri, 23 Jan 2015 15:42:24 +0900 [thread overview]
Message-ID: <20150123064224.30731.30127.stgit@localhost.localdomain> (raw)
In-Reply-To: <20150123064217.30731.49156.stgit@localhost.localdomain>
From: Wang Nan <wangnan0@huawei.com>
In original code, the probed instruction doesn't get optimized after
echo 0 > /sys/kernel/debug/kprobes/enabled
echo 1 > /sys/kernel/debug/kprobes/enabled
This is because original code checks kprobes_all_disarmed in
optimize_kprobe(), but this flag is turned off after calling that
function. Therefore, optimize_kprobe() will see
kprobes_all_disarmed == true and doesn't do the optimization.
This patch simply turns off kprobes_all_disarmed earlier to enable
optimization.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
kernel/kprobes.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 06f5830..9471710 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -2320,6 +2320,12 @@ static void arm_all_kprobes(void)
if (!kprobes_all_disarmed)
goto already_enabled;
+ /*
+ * optimize_kprobe() called by arm_kprobe() checks
+ * kprobes_all_disarmed, so set kprobes_all_disarmed before
+ * arm_kprobe.
+ */
+ kprobes_all_disarmed = false;
/* Arming kprobes doesn't optimize kprobe itself */
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
@@ -2328,7 +2334,6 @@ static void arm_all_kprobes(void)
arm_kprobe(p);
}
- kprobes_all_disarmed = false;
printk(KERN_INFO "Kprobes globally enabled\n");
already_enabled:
WARNING: multiple messages have this Message-ID (diff)
From: masami.hiramatsu.pt@hitachi.com (Masami Hiramatsu)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH -tip/urgent 1/2] [BUGFIX]kprobes: set kprobes_all_disarmed earlier to enable re-optimization.
Date: Fri, 23 Jan 2015 15:42:24 +0900 [thread overview]
Message-ID: <20150123064224.30731.30127.stgit@localhost.localdomain> (raw)
In-Reply-To: <20150123064217.30731.49156.stgit@localhost.localdomain>
From: Wang Nan <wangnan0@huawei.com>
In original code, the probed instruction doesn't get optimized after
echo 0 > /sys/kernel/debug/kprobes/enabled
echo 1 > /sys/kernel/debug/kprobes/enabled
This is because original code checks kprobes_all_disarmed in
optimize_kprobe(), but this flag is turned off after calling that
function. Therefore, optimize_kprobe() will see
kprobes_all_disarmed == true and doesn't do the optimization.
This patch simply turns off kprobes_all_disarmed earlier to enable
optimization.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
kernel/kprobes.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 06f5830..9471710 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -2320,6 +2320,12 @@ static void arm_all_kprobes(void)
if (!kprobes_all_disarmed)
goto already_enabled;
+ /*
+ * optimize_kprobe() called by arm_kprobe() checks
+ * kprobes_all_disarmed, so set kprobes_all_disarmed before
+ * arm_kprobe.
+ */
+ kprobes_all_disarmed = false;
/* Arming kprobes doesn't optimize kprobe itself */
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
@@ -2328,7 +2334,6 @@ static void arm_all_kprobes(void)
arm_kprobe(p);
}
- kprobes_all_disarmed = false;
printk(KERN_INFO "Kprobes globally enabled\n");
already_enabled:
next prev parent reply other threads:[~2015-01-23 6:42 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-23 6:42 [PATCH -tip/urgent 0/2]kprobes bugfixes around optprobe Masami Hiramatsu
2015-01-23 6:42 ` Masami Hiramatsu
2015-01-23 6:42 ` Masami Hiramatsu [this message]
2015-01-23 6:42 ` [PATCH -tip/urgent 1/2] [BUGFIX]kprobes: set kprobes_all_disarmed earlier to enable re-optimization Masami Hiramatsu
2015-02-05 22:49 ` Andrew Morton
2015-02-05 22:49 ` Andrew Morton
2015-01-23 6:42 ` [PATCH -tip/urgent 2/2] [BUGFIX]kprobes: makes kprobes/enabled works correctly for optimized kprobes Masami Hiramatsu
2015-01-23 6:42 ` Masami Hiramatsu
2015-01-26 5:38 ` [PATCH -tip/urgent 0/2]kprobes bugfixes around optprobe Wang Nan
2015-01-26 5:38 ` Wang Nan
2015-02-04 11:01 ` Wang Nan
2015-02-04 11:01 ` Wang Nan
2015-02-05 1:59 ` Wang Nan
2015-02-05 1:59 ` Wang Nan
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