ext4: replace BUG_ON with WARN_ONCE in ext4_end_bio()

Add fallback code and a WARN_ONCE() call instead of a BUG_ON() in
the ext4_end_bio() function.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

1 files changed, 10 insertions, 1 deletions

diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 208241b06662..1a82138ba739 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -297,8 +297,17 @@ static void ext4_end_bio(struct bio *bio)
 {
         ext4_io_end_t *io_end = bio->bi_private;
         sector_t bi_sector = bio->bi_iter.bi_sector;
+        char b[BDEVNAME_SIZE];
 
-        BUG_ON(!io_end);
+        if (WARN_ONCE(!io_end, "io_end is NULL: %s: sector %Lu len %u err %d\n",
+                      bdevname(bio->bi_bdev, b),
+                      (long long) bio->bi_iter.bi_sector,
+                      (unsigned) bio_sectors(bio),
+                      bio->bi_error)) {
+                ext4_finish_bio(bio);
+                bio_put(bio);
+                return;
+        }
         bio->bi_end_io = NULL;
 
         if (bio->bi_error) {