[PATCH v2 2/2] livepatch: Use static buffer for debugging messages under rq lock

From: Petr Mladek <pmladek@suse.com>
To: Jiri Kosina <jikos@kernel.org>,
	Josh Poimboeuf <jpoimboe@redhat.com>,
	Miroslav Benes <mbenes@suse.cz>
Cc: Joe Lawrence <joe.lawrence@redhat.com>,
	Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>,
	live-patching@vger.kernel.org, linux-kernel@vger.kernel.org,
	Petr Mladek <pmladek@suse.com>
Subject: [PATCH v2 2/2] livepatch: Use static buffer for debugging messages under rq lock
Date: Tue, 30 Apr 2019 11:10:49 +0200	[thread overview]
Message-ID: <20190430091049.30413-3-pmladek@suse.com> (raw)
In-Reply-To: <20190430091049.30413-1-pmladek@suse.com>

klp_try_switch_task() is called under klp_mutex. The buffer for
debugging messages might be static.

Signed-off-by: Petr Mladek <pmladek@suse.com>
---
 kernel/livepatch/transition.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c
index 8e0274075e75..d66086fd6d75 100644
--- a/kernel/livepatch/transition.c
+++ b/kernel/livepatch/transition.c
@@ -304,11 +304,11 @@ static int klp_check_stack(struct task_struct *task, char *err_buf)
  */
 static bool klp_try_switch_task(struct task_struct *task)
 {
+	static char err_buf[STACK_ERR_BUF_SIZE];
 	struct rq *rq;
 	struct rq_flags flags;
 	int ret;
 	bool success = false;
-	char err_buf[STACK_ERR_BUF_SIZE];
 
 	err_buf[0] = '\0';
 
@@ -351,7 +351,6 @@ static bool klp_try_switch_task(struct task_struct *task)
 		pr_debug("%s", err_buf);
 
 	return success;
-
 }
 
 /*
-- 
2.16.4

