[PATCH] f2fs: fix to invalidate dcc->f2fs_issue_discard in error path

[Chao Yu]

Otherwise, latter f2fs_stop_discard_thread() may access invalid
dcc->f2fs_issue_discard.

Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
 fs/f2fs/segment.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 460048f3c850..cf5f534aa887 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -2026,8 +2026,10 @@ int f2fs_start_discard_thread(struct f2fs_sb_info *sbi)
 
 	dcc->f2fs_issue_discard = kthread_run(issue_discard_thread, sbi,
 				"f2fs_discard-%u:%u", MAJOR(dev), MINOR(dev));
-	if (IS_ERR(dcc->f2fs_issue_discard))
+	if (IS_ERR(dcc->f2fs_issue_discard)) {
 		err = PTR_ERR(dcc->f2fs_issue_discard);
+		dcc->f2fs_issue_discard = NULL;
+	}
 
 	return err;
 }
-- 
2.25.1