raid: drop patch not applicable to 4.8.x

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

2 files changed, 0 insertions, 127 deletions

diff --git a/queue/md-raid1-10-fix-potential-deadlock.patch b/queue/md-raid1-10-fix-potential-deadlock.patch
deleted file mode 100644
index 678e00f..0000000
--- a/queue/md-raid1-10-fix-potential-deadlock.patch
+++ /dev/null
@@ -1,126 +0,0 @@
-From 61eb2b43b99ebdc9bc6bc83d9792257b243e7cb3 Mon Sep 17 00:00:00 2001
-From: Shaohua Li <shli@fb.com>
-Date: Tue, 28 Feb 2017 13:00:20 -0800
-Subject: [PATCH] md/raid1/10: fix potential deadlock
-
-commit 61eb2b43b99ebdc9bc6bc83d9792257b243e7cb3 upstream.
-
-Neil Brown pointed out a potential deadlock in raid 10 code with
-bio_split/chain. The raid1 code could have the same issue, but recent
-barrier rework makes it less likely to happen. The deadlock happens in
-below sequence:
-
-1. generic_make_request(bio), this will set current->bio_list
-2. raid10_make_request will split bio to bio1 and bio2
-3. __make_request(bio1), wait_barrer, add underlayer disk bio to
-current->bio_list
-4. __make_request(bio2), wait_barrer
-
-If raise_barrier happens between 3 & 4, since wait_barrier runs at 3,
-raise_barrier waits for IO completion from 3. And since raise_barrier
-sets barrier, 4 waits for raise_barrier. But IO from 3 can't be
-dispatched because raid10_make_request() doesn't finished yet.
-
-The solution is to adjust the IO ordering. Quotes from Neil:
-"
-It is much safer to:
-
-    if (need to split) {
-        split = bio_split(bio, ...)
-        bio_chain(...)
-        make_request_fn(split);
-        generic_make_request(bio);
-   } else
-        make_request_fn(mddev, bio);
-
-This way we first process the initial section of the bio (in 'split')
-which will queue some requests to the underlying devices.  These
-requests will be queued in generic_make_request.
-Then we queue the remainder of the bio, which will be added to the end
-of the generic_make_request queue.
-Then we return.
-generic_make_request() will pop the lower-level device requests off the
-queue and handle them first.  Then it will process the remainder
-of the original bio once the first section has been fully processed.
-"
-
-Note, this only happens in read path. In write path, the bio is flushed to
-underlaying disks either by blk flush (from schedule) or offladed to raid1/10d.
-It's queued in current->bio_list.
-
-Cc: Coly Li <colyli@suse.de>
-Cc: stable@vger.kernel.org (v3.14+, only the raid10 part)
-Suggested-by: NeilBrown <neilb@suse.com>
-Reviewed-by: Jack Wang <jinpu.wang@profitbricks.com>
-Signed-off-by: Shaohua Li <shli@fb.com>
-
-diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
-index 10c3865e1186..c33e96e33b8e 100644
---- a/drivers/md/raid1.c
-+++ b/drivers/md/raid1.c
-@@ -1587,9 +1587,30 @@ static void raid1_make_request(struct mddev *mddev, struct bio *bio)
- 			split = bio;
- 		}
- 
--		if (bio_data_dir(split) == READ)
-+		if (bio_data_dir(split) == READ) {
- 			raid1_read_request(mddev, split);
--		else
-+
-+			/*
-+			 * If a bio is splitted, the first part of bio will
-+			 * pass barrier but the bio is queued in
-+			 * current->bio_list (see generic_make_request). If
-+			 * there is a raise_barrier() called here, the second
-+			 * part of bio can't pass barrier. But since the first
-+			 * part bio isn't dispatched to underlaying disks yet,
-+			 * the barrier is never released, hence raise_barrier
-+			 * will alays wait. We have a deadlock.
-+			 * Note, this only happens in read path. For write
-+			 * path, the first part of bio is dispatched in a
-+			 * schedule() call (because of blk plug) or offloaded
-+			 * to raid10d.
-+			 * Quitting from the function immediately can change
-+			 * the bio order queued in bio_list and avoid the deadlock.
-+			 */
-+			if (split != bio) {
-+				generic_make_request(bio);
-+				break;
-+			}
-+		} else
- 			raid1_write_request(mddev, split);
- 	} while (split != bio);
- }
-diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
-index c4db6d1fb6a2..b1b1f982a722 100644
---- a/drivers/md/raid10.c
-+++ b/drivers/md/raid10.c
-@@ -1584,7 +1584,25 @@ static void raid10_make_request(struct mddev *mddev, struct bio *bio)
- 			split = bio;
- 		}
- 
-+		/*
-+		 * If a bio is splitted, the first part of bio will pass
-+		 * barrier but the bio is queued in current->bio_list (see
-+		 * generic_make_request). If there is a raise_barrier() called
-+		 * here, the second part of bio can't pass barrier. But since
-+		 * the first part bio isn't dispatched to underlaying disks
-+		 * yet, the barrier is never released, hence raise_barrier will
-+		 * alays wait. We have a deadlock.
-+		 * Note, this only happens in read path. For write path, the
-+		 * first part of bio is dispatched in a schedule() call
-+		 * (because of blk plug) or offloaded to raid10d.
-+		 * Quitting from the function immediately can change the bio
-+		 * order queued in bio_list and avoid the deadlock.
-+		 */
- 		__make_request(mddev, split);
-+		if (split != bio && bio_data_dir(bio) == READ) {
-+			generic_make_request(bio);
-+			break;
-+		}
- 	} while (split != bio);
- 
- 	/* In case raid10d snuck in to freeze_array */
--- 
-2.12.0
-
diff --git a/queue/series b/queue/series
index 3f7dfb7..5710a4c 100644
--- a/queue/series
+++ b/queue/series
@@ -9,7 +9,6 @@ perf-core-Fix-use-after-free-in-perf_release.patch
 perf-core-Fix-event-inheritance-on-fork.patch
 cpufreq-Fix-and-clean-up-show_cpuinfo_cur_freq.patch
 powerpc-boot-Fix-zImage-TOC-alignment.patch
-md-raid1-10-fix-potential-deadlock.patch
 target-pscsi-Fix-TYPE_TAPE-TYPE_MEDIMUM_CHANGER-expo.patch
 scsi-lpfc-Add-shutdown-method-for-kexec.patch
 scsi-libiscsi-add-lock-around-task-lists-to-fix-list.patch