This is a note to let you know that I've just added the patch titled
bcache: Fix flushes in writeback mode
to the 3.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bcache-fix-flushes-in-writeback-mode.patch
and it can be found in the queue-3.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From c0f04d88e46d14de51f4baebb6efafb7d59e9f96 Mon Sep 17 00:00:00 2001
From: Kent Overstreet <kmo@xxxxxxxxxxxxx>
Date: Mon, 23 Sep 2013 23:17:36 -0700
Subject: bcache: Fix flushes in writeback mode
From: Kent Overstreet <kmo@xxxxxxxxxxxxx>
commit c0f04d88e46d14de51f4baebb6efafb7d59e9f96 upstream.
In writeback mode, when we get a cache flush we need to make sure we
issue a flush to the backing device.
The code for sending down an extra flush was wrong - by cloning the bio
we were probably getting flags that didn't make sense for a bare flush,
and also the old code was firing for FUA bios, for which we don't need
to send a flush to the backing device.
This was causing data corruption somehow - the mechanism was never
determined, but this patch fixes it for the users that were seeing it.
Signed-off-by: Kent Overstreet <kmo@xxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/bcache/request.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -1056,14 +1056,17 @@ static void request_write(struct cached_
trace_bcache_writeback(s->orig_bio);
bch_writeback_add(dc, bio_sectors(bio));
- if (s->op.flush_journal) {
+ if (bio->bi_rw & REQ_FLUSH) {
/* Also need to send a flush to the backing device */
- s->op.cache_bio = bio_clone_bioset(bio, GFP_NOIO,
- dc->disk.bio_split);
+ struct bio *flush = bio_alloc_bioset(0, GFP_NOIO,
+ dc->disk.bio_split);
- bio->bi_size = 0;
- bio->bi_vcnt = 0;
- closure_bio_submit(bio, cl, s->d);
+ flush->bi_rw = WRITE_FLUSH;
+ flush->bi_bdev = bio->bi_bdev;
+ flush->bi_end_io = request_endio;
+ flush->bi_private = cl;
+
+ closure_bio_submit(flush, cl, s->d);
} else {
s->op.cache_bio = bio;
}
Patches currently in stable-queue which might be from kmo@xxxxxxxxxxxxx are
queue-3.10/bcache-fix-a-flush-fua-performance-bug.patch
queue-3.10/bcache-fix-for-when-no-journal-entries-are-found.patch
queue-3.10/block-fix-bio_copy_data.patch
queue-3.10/bcache-fix-for-handling-overlapping-extents-when-reading-in-a-btree-node.patch
queue-3.10/bcache-fix-a-dumb-cpu-spinning-bug-in-writeback.patch
queue-3.10/bcache-strip-endline-when-writing-the-label-through-sysfs.patch
queue-3.10/bcache-fix-flushes-in-writeback-mode.patch
queue-3.10/bcache-fix-a-shrinker-deadlock.patch
queue-3.10/bcache-fix-a-writeback-performance-regression.patch
queue-3.10/bcache-fix-a-dumb-journal-discard-bug.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html