This is a note to let you know that I've just added the patch titled dm cache: only use overwrite optimisation for promotion when in writeback mode to the 3.18-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: dm-cache-only-use-overwrite-optimisation-for-promotion-when-in-writeback-mode.patch and it can be found in the queue-3.18 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From f29a3147e251d7ae20d3194ff67f109d71e501b4 Mon Sep 17 00:00:00 2001 From: Joe Thornber <ejt@xxxxxxxxxx> Date: Thu, 27 Nov 2014 12:21:08 +0000 Subject: dm cache: only use overwrite optimisation for promotion when in writeback mode From: Joe Thornber <ejt@xxxxxxxxxx> commit f29a3147e251d7ae20d3194ff67f109d71e501b4 upstream. Overwrite causes the cache block and origin blocks to diverge, which is only allowed in writeback mode. Signed-off-by: Joe Thornber <ejt@xxxxxxxxxx> Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/md/dm-cache-target.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -1070,7 +1070,8 @@ static void issue_copy(struct dm_cache_m avoid = is_discarded_oblock(cache, mg->new_oblock); - if (!avoid && bio_writes_complete_block(cache, bio)) { + if (writeback_mode(&cache->features) && + !avoid && bio_writes_complete_block(cache, bio)) { issue_overwrite(mg, bio); return; } Patches currently in stable-queue which might be from ejt@xxxxxxxxxx are queue-3.18/dm-space-map-metadata-fix-sm_bootstrap_get_nr_blocks.patch queue-3.18/dm-thin-fix-missing-out-of-data-space-to-write-mode-transition-if-blocks-are-released.patch queue-3.18/dm-cache-fix-spurious-cell_defer-when-dealing-with-partial-block-at-end-of-device.patch queue-3.18/dm-thin-fix-inability-to-discard-blocks-when-in-out-of-data-space-mode.patch queue-3.18/dm-cache-only-use-overwrite-optimisation-for-promotion-when-in-writeback-mode.patch queue-3.18/dm-cache-dirty-flag-was-mistakenly-being-cleared-when-promoting-via-overwrite.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