--- /dev/null
+From c5f1e5adf956e3ba82d204c7c141a75da9fa449a Mon Sep 17 00:00:00 2001
+From: Kent Overstreet <kmo@daterainc.com>
+Date: Sun, 29 Nov 2015 17:18:33 -0800
+Subject: bcache: Add a cond_resched() call to gc
+
+From: Kent Overstreet <kmo@daterainc.com>
+
+commit c5f1e5adf956e3ba82d204c7c141a75da9fa449a upstream.
+
+Signed-off-by: Takashi Iwai <tiwai@suse.de>
+Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
+Cc: Kent Overstreet <kmo@daterainc.com>
+Signed-off-by: Jens Axboe <axboe@fb.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/md/bcache/btree.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/drivers/md/bcache/btree.c
++++ b/drivers/md/bcache/btree.c
+@@ -1641,6 +1641,7 @@ static void bch_btree_gc(struct cache_se
+ do {
+ ret = btree_root(gc_root, c, &op, &writes, &stats);
+ closure_sync(&writes);
++ cond_resched();
+
+ if (ret && ret != -EAGAIN)
+ pr_warn("gc failed!");
--- /dev/null
+From 627ccd20b4ad3ba836472468208e2ac4dfadbf03 Mon Sep 17 00:00:00 2001
+From: Kent Overstreet <kent.overstreet@gmail.com>
+Date: Sun, 29 Nov 2015 18:47:01 -0800
+Subject: bcache: Change refill_dirty() to always scan entire disk if necessary
+
+From: Kent Overstreet <kent.overstreet@gmail.com>
+
+commit 627ccd20b4ad3ba836472468208e2ac4dfadbf03 upstream.
+
+Previously, it would only scan the entire disk if it was starting from
+the very start of the disk - i.e. if the previous scan got to the end.
+
+This was broken by refill_full_stripes(), which updates last_scanned so
+that refill_dirty was never triggering the searched_from_start path.
+
+But if we change refill_dirty() to always scan the entire disk if
+necessary, regardless of what last_scanned was, the code gets cleaner
+and we fix that bug too.
+
+Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
+Signed-off-by: Jens Axboe <axboe@fb.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/md/bcache/writeback.c | 37 ++++++++++++++++++++++++++++++-------
+ 1 file changed, 30 insertions(+), 7 deletions(-)
+
+--- a/drivers/md/bcache/writeback.c
++++ b/drivers/md/bcache/writeback.c
+@@ -323,6 +323,10 @@ void bcache_dev_sectors_dirty_add(struct
+
+ static bool dirty_pred(struct keybuf *buf, struct bkey *k)
+ {
++ struct cached_dev *dc = container_of(buf, struct cached_dev, writeback_keys);
++
++ BUG_ON(KEY_INODE(k) != dc->disk.id);
++
+ return KEY_DIRTY(k);
+ }
+
+@@ -372,11 +376,24 @@ next:
+ }
+ }
+
++/*
++ * Returns true if we scanned the entire disk
++ */
+ static bool refill_dirty(struct cached_dev *dc)
+ {
+ struct keybuf *buf = &dc->writeback_keys;
++ struct bkey start = KEY(dc->disk.id, 0, 0);
+ struct bkey end = KEY(dc->disk.id, MAX_KEY_OFFSET, 0);
+- bool searched_from_start = false;
++ struct bkey start_pos;
++
++ /*
++ * make sure keybuf pos is inside the range for this disk - at bringup
++ * we might not be attached yet so this disk's inode nr isn't
++ * initialized then
++ */
++ if (bkey_cmp(&buf->last_scanned, &start) < 0 ||
++ bkey_cmp(&buf->last_scanned, &end) > 0)
++ buf->last_scanned = start;
+
+ if (dc->partial_stripes_expensive) {
+ refill_full_stripes(dc);
+@@ -384,14 +401,20 @@ static bool refill_dirty(struct cached_d
+ return false;
+ }
+
+- if (bkey_cmp(&buf->last_scanned, &end) >= 0) {
+- buf->last_scanned = KEY(dc->disk.id, 0, 0);
+- searched_from_start = true;
+- }
+-
++ start_pos = buf->last_scanned;
+ bch_refill_keybuf(dc->disk.c, buf, &end, dirty_pred);
+
+- return bkey_cmp(&buf->last_scanned, &end) >= 0 && searched_from_start;
++ if (bkey_cmp(&buf->last_scanned, &end) < 0)
++ return false;
++
++ /*
++ * If we get to the end start scanning again from the beginning, and
++ * only scan up to where we initially started scanning from:
++ */
++ buf->last_scanned = start;
++ bch_refill_keybuf(dc->disk.c, buf, &start_pos, dirty_pred);
++
++ return bkey_cmp(&buf->last_scanned, &start_pos) >= 0;
+ }
+
+ static int bch_writeback_thread(void *arg)
--- /dev/null
+From fecaee6f20ee122ad75402c53d8278f9bb142ddc Mon Sep 17 00:00:00 2001
+From: Zheng Liu <wenqing.lz@taobao.com>
+Date: Sun, 29 Nov 2015 17:19:32 -0800
+Subject: bcache: clear BCACHE_DEV_UNLINK_DONE flag when attaching a backing device
+
+From: Zheng Liu <wenqing.lz@taobao.com>
+
+commit fecaee6f20ee122ad75402c53d8278f9bb142ddc upstream.
+
+This bug can be reproduced by the following script:
+
+ #!/bin/bash
+
+ bcache_sysfs="/sys/fs/bcache"
+
+ function clear_cache()
+ {
+ if [ ! -e $bcache_sysfs ]; then
+ echo "no bcache sysfs"
+ exit
+ fi
+
+ cset_uuid=$(ls -l $bcache_sysfs|head -n 2|tail -n 1|awk '{print $9}')
+ sudo sh -c "echo $cset_uuid > /sys/block/sdb/sdb1/bcache/detach"
+ sleep 5
+ sudo sh -c "echo $cset_uuid > /sys/block/sdb/sdb1/bcache/attach"
+ }
+
+ for ((i=0;i<10;i++)); do
+ clear_cache
+ done
+
+The warning messages look like below:
+[ 275.948611] ------------[ cut here ]------------
+[ 275.963840] WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xb8/0xd0() (Tainted: P W
+--------------- )
+[ 275.979253] Hardware name: Tecal RH2285
+[ 275.994106] sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:09.0/0000:08:00.0/host4/target4:2:1/4:2:1:0/block/sdb/sdb1/bcache/cache'
+[ 276.024105] Modules linked in: bcache tcp_diag inet_diag ipmi_devintf ipmi_si ipmi_msghandler
+bonding 8021q garp stp llc ipv6 ext3 jbd loop sg iomemory_vsl(P) bnx2 microcode serio_raw i2c_i801
+i2c_core iTCO_wdt iTCO_vendor_support i7core_edac edac_core shpchp ext4 jbd2 mbcache megaraid_sas
+pata_acpi ata_generic ata_piix dm_mod [last unloaded: scsi_wait_scan]
+[ 276.072643] Pid: 2765, comm: sh Tainted: P W --------------- 2.6.32 #1
+[ 276.089315] Call Trace:
+[ 276.105801] [<ffffffff81070fe7>] ? warn_slowpath_common+0x87/0xc0
+[ 276.122650] [<ffffffff810710d6>] ? warn_slowpath_fmt+0x46/0x50
+[ 276.139361] [<ffffffff81205c08>] ? sysfs_add_one+0xb8/0xd0
+[ 276.156012] [<ffffffff8120609b>] ? sysfs_do_create_link+0x12b/0x170
+[ 276.172682] [<ffffffff81206113>] ? sysfs_create_link+0x13/0x20
+[ 276.189282] [<ffffffffa03bda21>] ? bcache_device_link+0xc1/0x110 [bcache]
+[ 276.205993] [<ffffffffa03bfa08>] ? bch_cached_dev_attach+0x478/0x4f0 [bcache]
+[ 276.222794] [<ffffffffa03c4a17>] ? bch_cached_dev_store+0x627/0x780 [bcache]
+[ 276.239680] [<ffffffff8116783a>] ? alloc_pages_current+0xaa/0x110
+[ 276.256594] [<ffffffff81203b15>] ? sysfs_write_file+0xe5/0x170
+[ 276.273364] [<ffffffff811887b8>] ? vfs_write+0xb8/0x1a0
+[ 276.290133] [<ffffffff811890b1>] ? sys_write+0x51/0x90
+[ 276.306368] [<ffffffff8100c072>] ? system_call_fastpath+0x16/0x1b
+[ 276.322301] ---[ end trace 9f5d4fcdd0c3edfb ]---
+[ 276.338241] ------------[ cut here ]------------
+[ 276.354109] WARNING: at /home/wenqing.lz/bcache/bcache/super.c:720
+bcache_device_link+0xdf/0x110 [bcache]() (Tainted: P W --------------- )
+[ 276.386017] Hardware name: Tecal RH2285
+[ 276.401430] Couldn't create device <-> cache set symlinks
+[ 276.401759] Modules linked in: bcache tcp_diag inet_diag ipmi_devintf ipmi_si ipmi_msghandler
+bonding 8021q garp stp llc ipv6 ext3 jbd loop sg iomemory_vsl(P) bnx2 microcode serio_raw i2c_i801
+i2c_core iTCO_wdt iTCO_vendor_support i7core_edac edac_core shpchp ext4 jbd2 mbcache megaraid_sas
+pata_acpi ata_generic ata_piix dm_mod [last unloaded: scsi_wait_scan]
+[ 276.465477] Pid: 2765, comm: sh Tainted: P W --------------- 2.6.32 #1
+[ 276.482169] Call Trace:
+[ 276.498610] [<ffffffff81070fe7>] ? warn_slowpath_common+0x87/0xc0
+[ 276.515405] [<ffffffff810710d6>] ? warn_slowpath_fmt+0x46/0x50
+[ 276.532059] [<ffffffffa03bda3f>] ? bcache_device_link+0xdf/0x110 [bcache]
+[ 276.548808] [<ffffffffa03bfa08>] ? bch_cached_dev_attach+0x478/0x4f0 [bcache]
+[ 276.565569] [<ffffffffa03c4a17>] ? bch_cached_dev_store+0x627/0x780 [bcache]
+[ 276.582418] [<ffffffff8116783a>] ? alloc_pages_current+0xaa/0x110
+[ 276.599341] [<ffffffff81203b15>] ? sysfs_write_file+0xe5/0x170
+[ 276.616142] [<ffffffff811887b8>] ? vfs_write+0xb8/0x1a0
+[ 276.632607] [<ffffffff811890b1>] ? sys_write+0x51/0x90
+[ 276.648671] [<ffffffff8100c072>] ? system_call_fastpath+0x16/0x1b
+[ 276.664756] ---[ end trace 9f5d4fcdd0c3edfc ]---
+
+We forget to clear BCACHE_DEV_UNLINK_DONE flag in bcache_device_attach()
+function when we attach a backing device first time. After detaching this
+backing device, this flag will be true and sysfs_remove_link() isn't called in
+bcache_device_unlink(). Then when we attach this backing device again,
+sysfs_create_link() will return EEXIST error in bcache_device_link().
+
+So the fix is trival and we clear this flag in bcache_device_link().
+
+Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
+Tested-by: Joshua Schmid <jschmid@suse.com>
+Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
+Cc: Kent Overstreet <kmo@daterainc.com>
+Signed-off-by: Jens Axboe <axboe@fb.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/md/bcache/super.c | 2 ++
+ 1 file changed, 2 insertions(+)
+
+--- a/drivers/md/bcache/super.c
++++ b/drivers/md/bcache/super.c
+@@ -712,6 +712,8 @@ static void bcache_device_link(struct bc
+ WARN(sysfs_create_link(&d->kobj, &c->kobj, "cache") ||
+ sysfs_create_link(&c->kobj, &d->kobj, d->name),
+ "Couldn't create device <-> cache set symlinks");
++
++ clear_bit(BCACHE_DEV_UNLINK_DONE, &d->flags);
+ }
+
+ static void bcache_device_detach(struct bcache_device *d)
--- /dev/null
+From 4d4d8573a8451acc9f01cbea24b7e55f04a252fe Mon Sep 17 00:00:00 2001
+From: Al Viro <viro@ZenIV.linux.org.uk>
+Date: Sun, 29 Nov 2015 17:20:59 -0800
+Subject: bcache: fix a leak in bch_cached_dev_run()
+
+From: Al Viro <viro@ZenIV.linux.org.uk>
+
+commit 4d4d8573a8451acc9f01cbea24b7e55f04a252fe upstream.
+
+Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
+Tested-by: Joshua Schmid <jschmid@suse.com>
+Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
+Cc: Kent Overstreet <kmo@daterainc.com>
+Signed-off-by: Jens Axboe <axboe@fb.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/md/bcache/super.c | 5 ++++-
+ 1 file changed, 4 insertions(+), 1 deletion(-)
+
+--- a/drivers/md/bcache/super.c
++++ b/drivers/md/bcache/super.c
+@@ -884,8 +884,11 @@ void bch_cached_dev_run(struct cached_de
+ buf[SB_LABEL_SIZE] = '\0';
+ env[2] = kasprintf(GFP_KERNEL, "CACHED_LABEL=%s", buf);
+
+- if (atomic_xchg(&dc->running, 1))
++ if (atomic_xchg(&dc->running, 1)) {
++ kfree(env[1]);
++ kfree(env[2]);
+ return;
++ }
+
+ if (!d->c &&
+ BDEV_STATE(&dc->sb) != BDEV_STATE_NONE) {
--- /dev/null
+From 2ef9ccbfcb90cf84bdba320a571b18b05c41101b Mon Sep 17 00:00:00 2001
+From: Zheng Liu <gnehzuil.liu@gmail.com>
+Date: Sun, 29 Nov 2015 17:17:05 -0800
+Subject: bcache: fix a livelock when we cause a huge number of cache misses
+
+From: Zheng Liu <gnehzuil.liu@gmail.com>
+
+commit 2ef9ccbfcb90cf84bdba320a571b18b05c41101b upstream.
+
+Subject : [PATCH v2] bcache: fix a livelock in btree lock
+Date : Wed, 25 Feb 2015 20:32:09 +0800 (02/25/2015 04:32:09 AM)
+
+This commit tries to fix a livelock in bcache. This livelock might
+happen when we causes a huge number of cache misses simultaneously.
+
+When we get a cache miss, bcache will execute the following path.
+
+->cached_dev_make_request()
+ ->cached_dev_read()
+ ->cached_lookup()
+ ->bch->btree_map_keys()
+ ->btree_root() <------------------------
+ ->bch_btree_map_keys_recurse() |
+ ->cache_lookup_fn() |
+ ->cached_dev_cache_miss() |
+ ->bch_btree_insert_check_key() -|
+ [If btree->seq is not equal to seq + 1, we should return
+ EINTR and traverse btree again.]
+
+In bch_btree_insert_check_key() function we first need to check upgrade
+flag (op->lock == -1), and when this flag is true we need to release
+read btree->lock and try to take write btree->lock. During taking and
+releasing this write lock, btree->seq will be monotone increased in
+order to prevent other threads modify this in cache miss (see btree.h:74).
+But if there are some cache misses caused by some requested, we could
+meet a livelock because btree->seq is always changed by others. Thus no
+one can make progress.
+
+This commit will try to take write btree->lock if it encounters a race
+when we traverse btree. Although it sacrifice the scalability but we
+can ensure that only one can modify the btree.
+
+Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
+Tested-by: Joshua Schmid <jschmid@suse.com>
+Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
+Cc: Joshua Schmid <jschmid@suse.com>
+Cc: Zhu Yanhai <zhu.yanhai@gmail.com>
+Cc: Kent Overstreet <kmo@daterainc.com>
+Signed-off-by: Jens Axboe <axboe@fb.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/md/bcache/btree.c | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+--- a/drivers/md/bcache/btree.c
++++ b/drivers/md/bcache/btree.c
+@@ -2037,8 +2037,10 @@ int bch_btree_insert_check_key(struct bt
+ rw_lock(true, b, b->level);
+
+ if (b->key.ptr[0] != btree_ptr ||
+- b->seq != seq + 1)
++ b->seq != seq + 1) {
++ op->lock = b->level;
+ goto out;
++ }
+ }
+
+ SET_KEY_PTRS(check_key, 1);
--- /dev/null
+From 8d16ce540c94c9d366eb36fc91b7154d92d6397b Mon Sep 17 00:00:00 2001
+From: Stefan Bader <stefan.bader@canonical.com>
+Date: Sun, 29 Nov 2015 18:44:49 -0800
+Subject: bcache: prevent crash on changing writeback_running
+
+From: Stefan Bader <stefan.bader@canonical.com>
+
+commit 8d16ce540c94c9d366eb36fc91b7154d92d6397b upstream.
+
+Added a safeguard in the shutdown case. At least while not being
+attached it is also possible to trigger a kernel bug by writing into
+writeback_running. This change adds the same check before trying to
+wake up the thread for that case.
+
+Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
+Cc: Kent Overstreet <kent.overstreet@gmail.com>
+Signed-off-by: Jens Axboe <axboe@fb.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/md/bcache/writeback.h | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+--- a/drivers/md/bcache/writeback.h
++++ b/drivers/md/bcache/writeback.h
+@@ -63,7 +63,8 @@ static inline bool should_writeback(stru
+
+ static inline void bch_writeback_queue(struct cached_dev *dc)
+ {
+- wake_up_process(dc->writeback_thread);
++ if (!IS_ERR_OR_NULL(dc->writeback_thread))
++ wake_up_process(dc->writeback_thread);
+ }
+
+ static inline void bch_writeback_add(struct cached_dev *dc)
--- /dev/null
+From 2ecf0cdb2b437402110ab57546e02abfa68a716b Mon Sep 17 00:00:00 2001
+From: Zheng Liu <wenqing.lz@taobao.com>
+Date: Sun, 29 Nov 2015 17:21:57 -0800
+Subject: bcache: unregister reboot notifier if bcache fails to unregister device
+
+From: Zheng Liu <wenqing.lz@taobao.com>
+
+commit 2ecf0cdb2b437402110ab57546e02abfa68a716b upstream.
+
+In bcache_init() function it forgot to unregister reboot notifier if
+bcache fails to unregister a block device. This commit fixes this.
+
+Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
+Tested-by: Joshua Schmid <jschmid@suse.com>
+Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
+Cc: Kent Overstreet <kmo@daterainc.com>
+Signed-off-by: Jens Axboe <axboe@fb.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/md/bcache/super.c | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+--- a/drivers/md/bcache/super.c
++++ b/drivers/md/bcache/super.c
+@@ -2086,8 +2086,10 @@ static int __init bcache_init(void)
+ closure_debug_init();
+
+ bcache_major = register_blkdev(0, "bcache");
+- if (bcache_major < 0)
++ if (bcache_major < 0) {
++ unregister_reboot_notifier(&reboot);
+ return bcache_major;
++ }
+
+ if (!(bcache_wq = create_workqueue("bcache")) ||
+ !(bcache_kobj = kobject_create_and_add("bcache", fs_kobj)) ||
netfilter-nf_tables-fix-bogus-warning-in-nft_data_uninit.patch
netfilter-ipt_rpfilter-remove-the-nh_scope-test-in-rpfilter_lookup_reverse.patch
netfilter-ip6t_synproxy-fix-null-pointer-dereference.patch
+bcache-fix-a-livelock-when-we-cause-a-huge-number-of-cache-misses.patch
+bcache-add-a-cond_resched-call-to-gc.patch
+bcache-clear-bcache_dev_unlink_done-flag-when-attaching-a-backing-device.patch
+bcache-fix-a-leak-in-bch_cached_dev_run.patch
+bcache-unregister-reboot-notifier-if-bcache-fails-to-unregister-device.patch
+bcache-prevent-crash-on-changing-writeback_running.patch
+bcache-change-refill_dirty-to-always-scan-entire-disk-if-necessary.patch
projects / thirdparty / kernel / stable-queue.git / commitdiff
