FAILED: patch "[PATCH] RAID1: ignore discard error" failed to apply to 4.4-stable tree

PATCH [email protected] 1 participant 1 message Nov 9, 2016

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2016-11-09 08:11 UTC #0 lore raw

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

Quoted 1 line

From e3f948cd3283e4fbe5907f1f3967c839912f480e Mon Sep 17 00:00:00 2001

From: Shaohua Li <[email protected]>
Date: Thu, 6 Oct 2016 14:09:16 -0700
Subject: [PATCH] RAID1: ignore discard error

If a write error occurs, raid1 will try to rewrite the bio in small chunk size. If the rewrite fails, raid1 will record the error in bad block. narrow_write_error will always use WRITE for the bio, but actually it could be a discard. Since discard bio hasn't payload, write the bio will cause different issues. But discard error isn't fatal, we can safely ignore it. This is what this patch does.

This issue should exist since discard is added, but only exposed with recent arbitrary bio size feature.

Reported-and-tested-by Sitsofe Wheeler <[email protected]>

Cc [email protected] (v3.6)

Signed-off-by Shaohua Li <[email protected]>

drivers/md/raid1.c +5 -2

index 1961d827dbd1..db536a68b2ee 100644
@@ -403,11 +403,14 @@ static void raid1_end_write_request(struct bio *bio)
 	struct bio *to_put = NULL;
 	int mirror = find_bio_disk(r1_bio, bio);
 	struct md_rdev *rdev = conf->mirrors[mirror].rdev;
+	bool discard_error;
+
+	discard_error = bio->bi_error && bio_op(bio) == REQ_OP_DISCARD;
 
 	/*
 	 * 'one mirror IO has finished' event handler:
 	 */
-	if (bio->bi_error) {
+	if (bio->bi_error && !discard_error) {
 		set_bit(WriteErrorSeen,	&rdev->flags);
 		if (!test_and_set_bit(WantReplacement, &rdev->flags))
 			set_bit(MD_RECOVERY_NEEDED, &

@@ -444,7 +447,7 @@ static void raid1_end_write_request(struct bio *bio)
 
 		/* Maybe we can clear some bad blocks. */
 		if (is_badblock(rdev, r1_bio->sector, r1_bio->sectors,
-				&first_bad, &bad_sectors)) {
+				&first_bad, &bad_sectors) && !discard_error) {
 			r1_bio->bios[mirror] = IO_MADE_GOOD;
 			set_bit(R1BIO_MadeGood, &r1_bio->state);
 		}