Patch "md: forbid a RAID5 from having both a bitmap and a journal." has been added to the 4.14-stable tree

[<gregkh@linuxfoundation.org>]

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;a=summary

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