Messages in this thread Patch in this message | | | Date | Thu, 19 Apr 2012 14:03:16 -0700 | From | Greg KH <> | Subject | [ 13/75] md/bitmap: prevent bitmap_daemon_work running while initialising bitmap |
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3.3-stable review patch. If anyone has any objections, please let me know.
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From: NeilBrown <neilb@suse.de>
commit afbaa90b80b1ec66e5137cc3824746bfdf559b18 upstream.
If a bitmap is added while the array is active, it is possible for bitmap_daemon_work to run while the bitmap is being initialised. This is particularly a problem if bitmap_daemon_work sees bitmap->filemap as non-NULL before it has been filled in properly. So hold bitmap_info.mutex while filling in ->filemap to prevent problems.
This patch is suitable for any -stable kernel, though it might not apply cleanly before about 3.1.
Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- drivers/md/bitmap.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -1819,7 +1819,9 @@ int bitmap_load(struct mddev *mddev) * re-add of a missing device */ start = mddev->recovery_cp; + mutex_lock(&mddev->bitmap_info.mutex); err = bitmap_init_from_disk(bitmap, start); + mutex_unlock(&mddev->bitmap_info.mutex); if (err) goto out;
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