This is a note to let you know that I've just added the patch titled

md: forbid a RAID5 from having both a bitmap and a journal.

to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: md-forbid-a-raid5-from-having-both-a-bitmap-and-a-journal.patch and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 230b55fa8d64007339319539f8f8e68114d08529 Mon Sep 17 00:00:00 2001

From: NeilBrown neilb@suse.com Date: Tue, 17 Oct 2017 14:24:09 +1100 Subject: md: forbid a RAID5 from having both a bitmap and a journal.

From: NeilBrown neilb@suse.com

commit 230b55fa8d64007339319539f8f8e68114d08529 upstream.

Having both a bitmap and a journal is pointless. Attempting to do so can corrupt the bitmap if the journal replay happens before the bitmap is initialized. Rather than try to avoid this corruption, simply refuse to allow arrays with both a bitmap and a journal. So: - if raid5_run sees both are present, fail. - if adding a bitmap finds a journal is present, fail - if adding a journal finds a bitmap is present, fail.

Signed-off-by: NeilBrown neilb@suse.com Tested-by: Joshua Kinard kumba@gentoo.org Acked-by: Joshua Kinard kumba@gentoo.org Signed-off-by: Shaohua Li shli@fb.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/md/bitmap.c | 6 ++++++ drivers/md/md.c | 2 +- drivers/md/raid5.c | 7 +++++++ 3 files changed, 14 insertions(+), 1 deletion(-)

--- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -1816,6 +1816,12 @@ struct bitmap *bitmap_create(struct mdde

BUG_ON(file && mddev->bitmap_info.offset);

+ if (test_bit(MD_HAS_JOURNAL, &mddev->flags)) { + pr_notice("md/raid:%s: array with journal cannot have bitmap\n", + mdname(mddev)); + return ERR_PTR(-EBUSY); + } + bitmap = kzalloc(sizeof(*bitmap), GFP_KERNEL); if (!bitmap) return ERR_PTR(-ENOMEM); --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -6362,7 +6362,7 @@ static int add_new_disk(struct mddev *md break; } } - if (has_journal) { + if (has_journal || mddev->bitmap) { export_rdev(rdev); return -EBUSY; } --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -7156,6 +7156,13 @@ static int raid5_run(struct mddev *mddev min_offset_diff = diff; }

+ if ((test_bit(MD_HAS_JOURNAL, &mddev->flags) || journal_dev) && + (mddev->bitmap_info.offset || mddev->bitmap_info.file)) { + pr_notice("md/raid:%s: array cannot have both journal and bitmap\n", + mdname(mddev)); + return -EINVAL; + } + if (mddev->reshape_position != MaxSector) { /* Check that we can continue the reshape. * Difficulties arise if the stripe we would write to

Patches currently in stable-queue which might be from neilb@suse.com are

queue-4.14/autofs-revert-autofs-fix-at_no_automount-not-being-honored.patch queue-4.14/md-forbid-a-raid5-from-having-both-a-bitmap-and-a-journal.patch queue-4.14/autofs-revert-autofs-take-more-care-to-not-update-last_used-on-path-walk.patch