Commit f36e6645 authored May 31, 2019 by Petr Mladek

livepatch: Use static buffer for debugging messages under rq lock



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>

parent 573de2a6

kernel/livepatch/transition.c

+1 −2

Original line number	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 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';

		@@ -340,7 +340,6 @@ static bool klp_try_switch_task(struct task_struct *task)
		pr_debug("%s", err_buf);

		return success;

		}

		/*