Unverified Commit 50a2fbeb authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!9803 v2 x86/ftrace: Disable lockdep check when execute ftrace_int3_handler() 

Merge Pull Request from: @ci-robot 
 
PR sync from: Zheng Yejian <zhengyejian1@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/A4LY4BPQYE5BZ5E7ETVUM6JE3BM2NH74/ 
 
https://gitee.com/openeuler/kernel/issues/IAA3U5 
 
Link:https://gitee.com/openeuler/kernel/pulls/9803

 

Reviewed-by: default avatarLiu YongQiang <liuyongqiang13@huawei.com>
Reviewed-by: default avatarXu Kuohai <xukuohai@huawei.com>
Reviewed-by: default avatarYe Weihua <yeweihua4@huawei.com>
Signed-off-by: default avatarZhang Changzhong <zhangchangzhong@huawei.com>
parents d127ee13 f9eb92f5

arch/x86/kernel/traps.c

+9 −3
Original line number Diff line number Diff line
@@ -585,9 +585,15 @@ dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code) 
	 * ftrace must be first, everything else may cause a recursive crash.

	 * See note by declaration of modifying_ftrace_code in ftrace.c

	 */

	if (unlikely(atomic_read(&modifying_ftrace_code)) &&

	    ftrace_int3_handler(regs))

	if (unlikely(atomic_read(&modifying_ftrace_code))) {

		int ret;



		lockdep_off();

		ret = ftrace_int3_handler(regs);

		lockdep_on();

		if (ret)

			return;

	}

#endif

	if (poke_int3_handler(regs))

		return;

kernel/trace/ftrace.c

+2 −8
Original line number Diff line number Diff line
@@ -1581,11 +1581,6 @@ unsigned long ftrace_location_range(unsigned long start, unsigned long end) 
	key.ip = start;

	key.flags = end;	/* overload flags, as it is unsigned long */



	/*

	 * It is in atomic context when called from ftrace_int3_handler(),

	 * in this case rcu lock is not needed.

	 */

	if (!in_atomic())

	rcu_read_lock();

	for (pg = ftrace_pages_start; pg; pg = pg->next) {

		if (pg->index == 0 ||
@@ -1600,7 +1595,6 @@ unsigned long ftrace_location_range(unsigned long start, unsigned long end) 
			break;

		}

	}

	if (!in_atomic())

	rcu_read_unlock();



	return ip;