4.4-stable patches

added patches:
	dm-io-fix-duplicate-bio-completion-due-to-missing-ref-count.patch

diff --git a/queue-4.4/dm-io-fix-duplicate-bio-completion-due-to-missing-ref-count.patch b/queue-4.4/dm-io-fix-duplicate-bio-completion-due-to-missing-ref-count.patch
new file mode 100644 (file)
index 0000000..ca2ae93
--- /dev/null
+++ b/queue-4.4/dm-io-fix-duplicate-bio-completion-due-to-missing-ref-count.patch
@@ -0,0 +1,37 @@
+From feb7695fe9fb83084aa29de0094774f4c9d4c9fc Mon Sep 17 00:00:00 2001
+From: Mike Snitzer <snitzer@redhat.com>
+Date: Tue, 20 Jun 2017 19:14:30 -0400
+Subject: dm io: fix duplicate bio completion due to missing ref count
+
+From: Mike Snitzer <snitzer@redhat.com>
+
+commit feb7695fe9fb83084aa29de0094774f4c9d4c9fc upstream.
+
+If only a subset of the devices associated with multiple regions support
+a given special operation (eg. DISCARD) then the dec_count() that is
+used to set error for the region must increment the io->count.
+
+Otherwise, when the dec_count() is called it can cause the dm-io
+caller's bio to be completed multiple times.  As was reported against
+the dm-mirror target that had mirror legs with a mix of discard
+capabilities.
+
+Bug: https://bugzilla.kernel.org/show_bug.cgi?id=196077
+Reported-by: Zhang Yi <yizhan@redhat.com>
+Signed-off-by: Mike Snitzer <snitzer@redhat.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/md/dm-io.c |    1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/drivers/md/dm-io.c
++++ b/drivers/md/dm-io.c
+@@ -300,6 +300,7 @@ static void do_region(int rw, unsigned r
+       else if (rw & REQ_WRITE_SAME)
+               special_cmd_max_sectors = q->limits.max_write_same_sectors;
+       if ((rw & (REQ_DISCARD | REQ_WRITE_SAME)) && special_cmd_max_sectors == 0) {
++              atomic_inc(&io->count);
+               dec_count(io, region, -EOPNOTSUPP);
+               return;
+       }

diff --git a/queue-4.4/series b/queue-4.4/series
index a935c53726556e41dca1ae5bf5a06bbbe3c51ca0..51232dbe8c0a9c0a3cecedd425981fc62435a1b7 100644 (file)
--- a/queue-4.4/series
+++ b/queue-4.4/series
@@ -31,3 +31,4 @@ s390-qeth-fix-ipa-command-submission-race.patch
 sctp-verify-size-of-a-new-chunk-in-_sctp_make_chunk.patch
 net-mpls-pull-common-label-check-into-helper.patch
 mpls-nospec-sanitize-array-index-in-mpls_label_ok.patch
+dm-io-fix-duplicate-bio-completion-due-to-missing-ref-count.patch