From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
Kent Overstreet <kent.overstreet@gmail.com>,
Eric Wheeler <bcache@linux.ewheeler.net>
Subject: [PATCH 4.7 39/59] bcache: RESERVE_PRIO is too small by one when prio_buckets() is a power of two.
Date: Mon, 12 Sep 2016 17:29:59 +0200 [thread overview]
Message-ID: <20160912152130.415654636@linuxfoundation.org> (raw)
In-Reply-To: <20160912152128.765864031@linuxfoundation.org>
4.7-stable review patch. If anyone has any objections, please let me know.
------------------
From: Kent Overstreet <kent.overstreet@gmail.com>
commit acc9cf8c66c66b2cbbdb4a375537edee72be64df upstream.
This patch fixes a cachedev registration-time allocation deadlock.
This can deadlock on boot if your initrd auto-registeres bcache devices:
Allocator thread:
[ 720.727614] INFO: task bcache_allocato:3833 blocked for more than 120 seconds.
[ 720.732361] [<ffffffff816eeac7>] schedule+0x37/0x90
[ 720.732963] [<ffffffffa05192b8>] bch_bucket_alloc+0x188/0x360 [bcache]
[ 720.733538] [<ffffffff810e6950>] ? prepare_to_wait_event+0xf0/0xf0
[ 720.734137] [<ffffffffa05302bd>] bch_prio_write+0x19d/0x340 [bcache]
[ 720.734715] [<ffffffffa05190bf>] bch_allocator_thread+0x3ff/0x470 [bcache]
[ 720.735311] [<ffffffff816ee41c>] ? __schedule+0x2dc/0x950
[ 720.735884] [<ffffffffa0518cc0>] ? invalidate_buckets+0x980/0x980 [bcache]
Registration thread:
[ 720.710403] INFO: task bash:3531 blocked for more than 120 seconds.
[ 720.715226] [<ffffffff816eeac7>] schedule+0x37/0x90
[ 720.715805] [<ffffffffa05235cd>] __bch_btree_map_nodes+0x12d/0x150 [bcache]
[ 720.716409] [<ffffffffa0522d30>] ? bch_btree_insert_check_key+0x1c0/0x1c0 [bcache]
[ 720.717008] [<ffffffffa05236e4>] bch_btree_insert+0xf4/0x170 [bcache]
[ 720.717586] [<ffffffff810e6950>] ? prepare_to_wait_event+0xf0/0xf0
[ 720.718191] [<ffffffffa0527d9a>] bch_journal_replay+0x14a/0x290 [bcache]
[ 720.718766] [<ffffffff810cc90d>] ? ttwu_do_activate.constprop.94+0x5d/0x70
[ 720.719369] [<ffffffff810cf684>] ? try_to_wake_up+0x1d4/0x350
[ 720.719968] [<ffffffffa05317d0>] run_cache_set+0x580/0x8e0 [bcache]
[ 720.720553] [<ffffffffa053302e>] register_bcache+0xe2e/0x13b0 [bcache]
[ 720.721153] [<ffffffff81354cef>] kobj_attr_store+0xf/0x20
[ 720.721730] [<ffffffff812a2dad>] sysfs_kf_write+0x3d/0x50
[ 720.722327] [<ffffffff812a225a>] kernfs_fop_write+0x12a/0x180
[ 720.722904] [<ffffffff81225177>] __vfs_write+0x37/0x110
[ 720.723503] [<ffffffff81228048>] ? __sb_start_write+0x58/0x110
[ 720.724100] [<ffffffff812cedb3>] ? security_file_permission+0x23/0xa0
[ 720.724675] [<ffffffff812258a9>] vfs_write+0xa9/0x1b0
[ 720.725275] [<ffffffff8102479c>] ? do_audit_syscall_entry+0x6c/0x70
[ 720.725849] [<ffffffff81226755>] SyS_write+0x55/0xd0
[ 720.726451] [<ffffffff8106a390>] ? do_page_fault+0x30/0x80
[ 720.727045] [<ffffffff816f2cae>] system_call_fastpath+0x12/0x71
The fifo code in upstream bcache can't use the last element in the buffer,
which was the cause of the bug: if you asked for a power of two size,
it'd give you a fifo that could hold one less than what you asked for
rather than allocating a buffer twice as big.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/md/bcache/super.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1818,7 +1818,7 @@ static int cache_alloc(struct cache_sb *
free = roundup_pow_of_two(ca->sb.nbuckets) >> 10;
if (!init_fifo(&ca->free[RESERVE_BTREE], 8, GFP_KERNEL) ||
- !init_fifo(&ca->free[RESERVE_PRIO], prio_buckets(ca), GFP_KERNEL) ||
+ !init_fifo_exact(&ca->free[RESERVE_PRIO], prio_buckets(ca), GFP_KERNEL) ||
!init_fifo(&ca->free[RESERVE_MOVINGGC], free, GFP_KERNEL) ||
!init_fifo(&ca->free[RESERVE_NONE], free, GFP_KERNEL) ||
!init_fifo(&ca->free_inc, free << 2, GFP_KERNEL) ||
next prev parent reply other threads:[~2016-09-12 15:29 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20160912153038uscas1p166159f601d12fb1e6621d90d3ef5d311@uscas1p1.samsung.com>
[not found] ` <20160912152128.765864031@linuxfoundation.org>
2016-09-12 15:29 ` [PATCH 4.7 01/59] Revert "floppy: refactor open() flags handling" Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 02/59] apparmor: fix refcount race when finding a child profile Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 03/59] kernel: Add noaudit variant of ns_capable() Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 04/59] net: Use ns_capable_noaudit() when determining net sysctl permissions Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 05/59] fs: Check for invalid i_uid in may_follow_link() Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 06/59] cred: Reject inodes with invalid ids in set_create_file_as() Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 07/59] ext4: validate that metadata blocks do not overlap superblock Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 08/59] ext4: fix xattr shifting when expanding inodes Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 09/59] ext4: fix xattr shifting when expanding inodes part 2 Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 10/59] ext4: properly align shifted xattrs when expanding inodes Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 11/59] ext4: avoid deadlock when expanding inode size Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 13/59] block: Fix race triggered by blk_set_queue_dying() Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 14/59] block: make sure a big bio is split into at most 256 bvecs Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 15/59] cgroup: reduce read locked section of cgroup_threadgroup_rwsem during fork Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 16/59] cdc-acm: added sanity checking for probe() Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 19/59] drm/atomic: Dont potentially reset color_mgmt_changed on successive property updates Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 20/59] drm: Reject page_flip for !DRIVER_MODESET Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 21/59] drm/msm: fix use of copy_from_user() while holding spinlock Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 22/59] drm/vc4: Use drm_free_large() on handles to match its allocation Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 23/59] drm/vc4: Fix overflow mem unreferencing when the binner runs dry Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 24/59] drm/vc4: Fix oops when userspace hands in a bad BO Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 25/59] ASoC: atmel_ssc_dai: Dont unconditionally reset SSC on stream startup Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 26/59] xfs: fix superblock inprogress check Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 27/59] timekeeping: Cap array access in timekeeping_debug Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 28/59] timekeeping: Avoid taking lock in NMI path with CONFIG_DEBUG_TIMEKEEPING Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 30/59] ovl: proper cleanup of workdir Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 31/59] ovl: dont copy up opaqueness Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 32/59] ovl: remove posix_acl_default from workdir Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 33/59] ovl: listxattr: use strnlen() Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 34/59] ovl: fix workdir creation Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 35/59] mei: me: disable driver on SPT SPS firmware Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 36/59] ubifs: Fix xattr generic handler usage Greg Kroah-Hartman
2016-09-12 15:29 ` [PATCH 4.7 38/59] bdev: fix NULL pointer dereference Greg Kroah-Hartman
2016-09-12 15:29 ` Greg Kroah-Hartman [this message]
2016-09-12 15:30 ` [PATCH 4.7 40/59] irqchip/mips-gic: Cleanup chip and handler setup Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 41/59] irqchip/mips-gic: Implement activate op for device domain Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 42/59] vhost/scsi: fix reuse of &vq->iov[out] in response Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 43/59] x86/apic: Do not init irq remapping if ioapic is disabled Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 44/59] xprtrdma: Create common scatterlist fields in rpcrdma_mw Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 46/59] fscrypto: add authorization check for setting encryption policy Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 47/59] fscrypto: only allow setting encryption policy on directories Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 48/59] ALSA: usb-audio: Add sample rate inquiry quirk for B850V3 CP2114 Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 49/59] ALSA: firewire-tascam: accessing to user space outside spinlock Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 50/59] ALSA: fireworks: " Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 51/59] ALSA: rawmidi: Fix possible deadlock with virmidi registration Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 52/59] ALSA: hda - Add headset mic quirk for Dell Inspiron 5468 Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 53/59] ALSA: hda - Enable subwoofer on Dell Inspiron 7559 Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 54/59] ALSA: timer: fix NULL pointer dereference in read()/ioctl() race Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 55/59] ALSA: timer: fix division by zero after SNDRV_TIMER_IOCTL_CONTINUE Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 56/59] ALSA: timer: fix NULL pointer dereference on memory allocation failure Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 57/59] ALSA: timer: Fix zero-division by continue of uninitialized instance Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 58/59] scsi: fix upper bounds check of sense key in scsi_sense_key_string() Greg Kroah-Hartman
2016-09-12 15:30 ` [PATCH 4.7 59/59] cpufreq: dt: Add terminate entry for of_device_id tables Greg Kroah-Hartman
2016-09-13 3:07 ` [PATCH 4.7 00/59] 4.7.4-stable review Guenter Roeck
2016-09-13 8:57 ` Greg Kroah-Hartman
[not found] ` <57d7cc1f.0d8d1c0a.df2d3.a693@mx.google.com>
2016-09-13 12:12 ` Greg Kroah-Hartman
2016-09-13 17:40 ` Kevin Hilman
2016-09-13 18:32 ` Shuah Khan
2016-09-15 6:19 ` Greg Kroah-Hartman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160912152130.415654636@linuxfoundation.org \
--to=gregkh@linuxfoundation.org \
--cc=bcache@linux.ewheeler.net \
--cc=kent.overstreet@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).