livepatch: Use static buffer for debugging messages under rq lock (f36e6645) · Commits · 戴 / test

The err_buf array uses 128 bytes of stack space. Move it off the stack by making it static. It's safe to use a shared buffer because klp_try_switch_task() is called under klp_mutex. Acked-by:

Miroslav Benes <mbenes@suse.cz> Acked-by:

Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by:

Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by:

Petr Mladek <pmladek@suse.com>

kernel/livepatch/transition.c

+1 −2

Original line number	Original line	Diff line number	Diff line
	@@ -293,11 +293,11 @@ static int klp_check_stack(struct task_struct task, char err_buf)
	*/		*/
	static bool klp_try_switch_task(struct task_struct *task)		static bool klp_try_switch_task(struct task_struct *task)
	{		{
			static char err_buf[STACK_ERR_BUF_SIZE];
	struct rq *rq;		struct rq *rq;
	struct rq_flags flags;		struct rq_flags flags;
	int ret;		int ret;
	bool success = false;		bool success = false;
	char err_buf[STACK_ERR_BUF_SIZE];

	err_buf[0] = '\0';		err_buf[0] = '\0';

	@@ -340,7 +340,6 @@ done:
	pr_debug("%s", err_buf);		pr_debug("%s", err_buf);

	return success;		return success;

	}		}

	/*		/*

Admin message