Patch "dm thin: restore requested 'error_if_no_space' setting on OODS to WRITE transition" has been added to the 3.14-stable tree

Patch "dm thin: restore requested 'error_if_no_space' setting on OODS to WRITE transition" has been added to the 3.14-stable tree

[gregkh]

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

    dm thin: restore requested 'error_if_no_space' setting on OODS to WRITE transition

to the 3.14-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:
     dm-thin-restore-requested-error_if_no_space-setting-on-oods-to-write-transition.patch
and it can be found in the queue-3.14 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 172c238612ebf81cabccc86b788c9209af591f61 Mon Sep 17 00:00:00 2001
From: Mike Snitzer <snitzer@redhat.com>
Date: Fri, 6 Nov 2015 10:53:01 -0500
Subject: dm thin: restore requested 'error_if_no_space' setting on OODS to WRITE transition

From: Mike Snitzer <snitzer@redhat.com>

commit 172c238612ebf81cabccc86b788c9209af591f61 upstream.

A thin-pool that is in out-of-data-space (OODS) mode may transition back
to write mode -- without the admin adding more space to the thin-pool --
if/when blocks are released (either by deleting thin devices or
discarding provisioned blocks).

But as part of the thin-pool's earlier transition to out-of-data-space
mode the thin-pool may have set the 'error_if_no_space' flag to true if
the no_space_timeout expires without more space having been made
available.  That implementation detail, of changing the pool's
error_if_no_space setting, needs to be reset back to the default that
the user specified when the thin-pool's table was loaded.

Otherwise we'll drop the user requested behaviour on the floor when this
out-of-data-space to write mode transition occurs.

Reported-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Fixes: 2c43fd26e4 ("dm thin: fix missing out-of-data-space to write mode transition if blocks are released")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/md/dm-thin.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -1619,6 +1619,7 @@ static void set_pool_mode(struct pool *p
 	case PM_WRITE:
 		if (old_mode != new_mode)
 			notify_of_pool_mode_change(pool, "write");
+		pool->pf.error_if_no_space = pt->requested_pf.error_if_no_space;
 		dm_pool_metadata_read_write(pool->pmd);
 		pool->process_bio = process_bio;
 		pool->process_discard = process_discard;


Patches currently in stable-queue which might be from snitzer@redhat.com are

queue-3.14/dm-thin-restore-requested-error_if_no_space-setting-on-oods-to-write-transition.patch
queue-3.14/dm-thin-fix-race-condition-when-destroying-thin-pool-workqueue.patch
queue-3.14/dm-thin-metadata-fix-bug-when-taking-a-metadata-snapshot.patch