All of lore.kernel.org
 help / color / mirror / Atom feed
From: Sasha Levin <sasha.levin-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
To: koverstreet-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org,
	NeilBrown <neilb-l3A5Bk7waGM@public.gmane.org>
Cc: linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	linux-raid-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	"linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
	<linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
Subject: bcache: BUG in fuzz testing without devices
Date: Tue, 02 Apr 2013 12:21:02 -0400	[thread overview]
Message-ID: <515B056E.6010002@oracle.com> (raw)

Hi all,

It seems that trying to fuzz bcache without any devices triggers a BUG:

sh-4.2# echo 1 > /sys/fs/bcache/fuzz
[   89.700458] bio: create slab <bio-1> at 1
[   89.704543] ------------[ cut here ]------------
[   89.710043] kernel BUG at drivers/md/bcache/debug.c:447!
[   89.710043] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[   89.710043] Modules linked in:
[   89.710043] CPU 2
[   89.710043] Pid: 6885, comm: sh Tainted: G        W    3.9.0-rc4-next-20130328-sasha-00017-g1463000 #321
[   89.710043] RIP: 0010:[<ffffffff8324c005>]  [<ffffffff8324c005>] btree_fuzz+0x95/0x720
[   89.710043] RSP: 0018:ffff880035279be8  EFLAGS: 00010246
[   89.710043] RAX: ffff880034720000 RBX: ffff880034721030 RCX: ffff8800353af400
[   89.710043] RDX: 0000000000000000 RSI: ffff880034723b18 RDI: ffff88003477a960
[   89.710043] RBP: ffff880035279e88 R08: ffff88003477a900 R09: ffff88003d801e00
[   89.710043] R10: 000000000048d002 R11: 0000000000000000 R12: ffff880035279c18
[   89.710043] R13: ffff880034721030 R14: ffff880034720000 R15: ffff880035279c30
[   89.710043] FS:  00007f591db62700(0000) GS:ffff88003e000000(0000) knlGS:0000000000000000
[   89.710043] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   89.710043] CR2: 00007f591db8e000 CR3: 0000000035bf0000 CR4: 00000000000406e0
[   89.710043] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   89.710043] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[   89.710043] Process sh (pid: 6885, threadinfo ffff880035278000, task ffff880037060000)
[   89.710043] Stack:
[   89.710043]  ffffffff84c1b104 ffffffff83e20320 000000000000d8e0 ffff880035279ca8
[   89.710043]  ffff88003e00a000 ffff880035278000 ffff880035279fd8 ffff88003e1d7cd0
[   89.710043]  ffff880035279c58 0000000000000000 0000000000000000 0000000000000000
[   89.710043] Call Trace:
[   89.710043]  [<ffffffff812ffd92>] ? sysfs_write_file+0xe2/0x150
[   89.710043]  [<ffffffff819fff5f>] kobj_attr_store+0xf/0x20
[   89.710043]  [<ffffffff812ffdaa>] sysfs_write_file+0xfa/0x150
[   89.710043]  [<ffffffff8127eff0>] vfs_write+0xb0/0x180
[   89.710043]  [<ffffffff8127f480>] SyS_write+0x50/0xa0
[   89.710043]  [<ffffffff83db7e58>] tracesys+0xe1/0xe6
[   89.710043] Code: c0 49 89 c6 0f 84 2c 06 00 00 4c 8d a5 90 fd ff ff 4c 8d a8 30 10 00 00 4d 89 e7 49 83 c7 18 49 8b 9e 30 10
00 00 4c 39 eb 75 0b <0f> 0b 66 0f 1f 84 00 00 00 00 00 48 8d 83 a0 fd ff ff 48 89 df
[   89.710043] RIP  [<ffffffff8324c005>] btree_fuzz+0x95/0x720
[   89.710043]  RSP <ffff880035279be8>
[   89.755259] ---[ end trace d6647580839fba22 ]---

That BUG looks very intentional there, any reason for adding it instead of exiting
if there aren't any devices?


Thanks,
Sasha

WARNING: multiple messages have this Message-ID (diff)
From: Sasha Levin <sasha.levin@oracle.com>
To: koverstreet@google.com, NeilBrown <neilb@suse.de>
Cc: linux-bcache@vger.kernel.org, linux-raid@vger.kernel.org,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: bcache: BUG in fuzz testing without devices
Date: Tue, 02 Apr 2013 12:21:02 -0400	[thread overview]
Message-ID: <515B056E.6010002@oracle.com> (raw)

Hi all,

It seems that trying to fuzz bcache without any devices triggers a BUG:

sh-4.2# echo 1 > /sys/fs/bcache/fuzz
[   89.700458] bio: create slab <bio-1> at 1
[   89.704543] ------------[ cut here ]------------
[   89.710043] kernel BUG at drivers/md/bcache/debug.c:447!
[   89.710043] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[   89.710043] Modules linked in:
[   89.710043] CPU 2
[   89.710043] Pid: 6885, comm: sh Tainted: G        W    3.9.0-rc4-next-20130328-sasha-00017-g1463000 #321
[   89.710043] RIP: 0010:[<ffffffff8324c005>]  [<ffffffff8324c005>] btree_fuzz+0x95/0x720
[   89.710043] RSP: 0018:ffff880035279be8  EFLAGS: 00010246
[   89.710043] RAX: ffff880034720000 RBX: ffff880034721030 RCX: ffff8800353af400
[   89.710043] RDX: 0000000000000000 RSI: ffff880034723b18 RDI: ffff88003477a960
[   89.710043] RBP: ffff880035279e88 R08: ffff88003477a900 R09: ffff88003d801e00
[   89.710043] R10: 000000000048d002 R11: 0000000000000000 R12: ffff880035279c18
[   89.710043] R13: ffff880034721030 R14: ffff880034720000 R15: ffff880035279c30
[   89.710043] FS:  00007f591db62700(0000) GS:ffff88003e000000(0000) knlGS:0000000000000000
[   89.710043] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   89.710043] CR2: 00007f591db8e000 CR3: 0000000035bf0000 CR4: 00000000000406e0
[   89.710043] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   89.710043] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[   89.710043] Process sh (pid: 6885, threadinfo ffff880035278000, task ffff880037060000)
[   89.710043] Stack:
[   89.710043]  ffffffff84c1b104 ffffffff83e20320 000000000000d8e0 ffff880035279ca8
[   89.710043]  ffff88003e00a000 ffff880035278000 ffff880035279fd8 ffff88003e1d7cd0
[   89.710043]  ffff880035279c58 0000000000000000 0000000000000000 0000000000000000
[   89.710043] Call Trace:
[   89.710043]  [<ffffffff812ffd92>] ? sysfs_write_file+0xe2/0x150
[   89.710043]  [<ffffffff819fff5f>] kobj_attr_store+0xf/0x20
[   89.710043]  [<ffffffff812ffdaa>] sysfs_write_file+0xfa/0x150
[   89.710043]  [<ffffffff8127eff0>] vfs_write+0xb0/0x180
[   89.710043]  [<ffffffff8127f480>] SyS_write+0x50/0xa0
[   89.710043]  [<ffffffff83db7e58>] tracesys+0xe1/0xe6
[   89.710043] Code: c0 49 89 c6 0f 84 2c 06 00 00 4c 8d a5 90 fd ff ff 4c 8d a8 30 10 00 00 4d 89 e7 49 83 c7 18 49 8b 9e 30 10
00 00 4c 39 eb 75 0b <0f> 0b 66 0f 1f 84 00 00 00 00 00 48 8d 83 a0 fd ff ff 48 89 df
[   89.710043] RIP  [<ffffffff8324c005>] btree_fuzz+0x95/0x720
[   89.710043]  RSP <ffff880035279be8>
[   89.755259] ---[ end trace d6647580839fba22 ]---

That BUG looks very intentional there, any reason for adding it instead of exiting
if there aren't any devices?


Thanks,
Sasha

             reply	other threads:[~2013-04-02 16:21 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-04-02 16:21 Sasha Levin [this message]
2013-04-02 16:21 ` bcache: BUG in fuzz testing without devices Sasha Levin
     [not found] ` <515B056E.6010002-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
2013-04-05 21:21   ` Kent Overstreet
2013-04-05 21:21     ` Kent Overstreet

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=515B056E.6010002@oracle.com \
    --to=sasha.levin-qhclzuegtsvqt0dzr+alfa@public.gmane.org \
    --cc=koverstreet-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org \
    --cc=linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=linux-raid-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=neilb-l3A5Bk7waGM@public.gmane.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.