Re: [PATCH V2 0/3] drivers/staging: zcache: dynamic page cache/swap compression

From: Matt
Date: Tue Feb 15 2011 - 18:48:40 EST


On Mon, Feb 14, 2011 at 8:59 PM, Matt <jackdachef@xxxxxxxxx> wrote:
> On Mon, Feb 14, 2011 at 1:29 AM, Matt <jackdachef@xxxxxxxxx> wrote:
>> On Mon, Feb 14, 2011 at 1:24 AM, Matt <jackdachef@xxxxxxxxx> wrote:
>>> On Mon, Feb 14, 2011 at 12:08 AM, Matt <jackdachef@xxxxxxxxx> wrote:
>>>> On Wed, Feb 9, 2011 at 1:03 AM, Dan Magenheimer
>>>> <dan.magenheimer@xxxxxxxxxx> wrote:
>>>> [snip]
>>>>>
>>>>> If I've missed anything important, please let me know!
>>>>>
>>>>> Thanks again!
>>>>> Dan
>>>>>
>>>>
>>>> Hi Dan,
>>>>
>>>> thank you so much for answering my email in such detail !
>>>>
>>>> I shall pick up on that mail in my next email sending to the mailing list :)
>>>>
>>>>
>>>> currently I've got a problem with btrfs which seems to get triggered
>>>> by cleancache get-operations:
>>>>
>>>>
>>>> Feb 14 00:37:19 lupus kernel: [ 2831.297377] device fsid
>>>> 354120c992a00761-5fa07d400126a895 devid 1 transid 7
>>>> /dev/mapper/portage
>>>> Feb 14 00:37:19 lupus kernel: [ 2831.297698] btrfs: enabling disk space caching
>>>> Feb 14 00:37:19 lupus kernel: [ 2831.297700] btrfs: force lzo compression
>>>> Feb 14 00:37:19 lupus kernel: [ 2831.315844] zcache: created ephemeral
>>>> tmem pool, id=3
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853188] BUG: unable to handle
>>>> kernel paging request at 0000000001400050
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853219] IP: [<ffffffff8133ef1b>]
>>>> btrfs_encode_fh+0x2b/0x120
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853242] PGD 0
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853251] Oops: 0000 [#1] PREEMPT SMP
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853275] last sysfs file:
>>>> /sys/devices/platform/coretemp.3/temp1_input
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853295] CPU 4
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853303] Modules linked in: radeon
>>>> ttm drm_kms_helper cfbcopyarea cfbimgblt cfbfillrect ipt_REJECT
>>>> ipt_LOG xt_limit xt_tcpudp xt_state nf_nat_irc nf_conntrack_irc
>>>> nf_nat_ftp nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_conntrack_ftp
>>>> iptable_filter ipt_addrtype xt_DSCP xt_dscp xt_iprange ip_tables
>>>> ip6table_filter xt_NFQUEUE xt_owner xt_hashlimit xt_conntrack xt_mark
>>>> xt_multiport xt_connmark nf_conntrack xt_string ip6_tables x_tables
>>>> it87 hwmon_vid coretemp snd_seq_dummy snd_seq_oss snd_seq_midi_event
>>>> snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss snd_hda_codec_hdmi
>>>> snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_pcm
>>>> snd_timer snd soundcore i2c_i801 wmi e1000e shpchp snd_page_alloc
>>>> libphy e1000 scsi_wait_scan sl811_hcd ohci_hcd ssb usb_storage
>>>> ehci_hcd [last unloaded: tg3]
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853682]
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853690] Pid: 11394, comm:
>>>> btrfs-transacti Not tainted 2.6.37-plus_v16_zcache #4 FMP55/ipower
>>>> G3710
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853725] RIP:
>>>> 0010:[<ffffffff8133ef1b>]  [<ffffffff8133ef1b>]
>>>> btrfs_encode_fh+0x2b/0x120
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853751] RSP:
>>>> 0018:ffff880129a11b00  EFLAGS: 00010246
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853767] RAX: 00000000000000ff
>>>> RBX: ffff88014a1ce628 RCX: 0000000000000000
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853788] RDX: ffff880129a11b3c
>>>> RSI: ffff880129a11b70 RDI: 0000000000000006
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853808] RBP: 0000000001400000
>>>> R08: ffffffff8133eef0 R09: ffff880129a11c68
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853829] R10: 0000000000000001
>>>> R11: 0000000000000001 R12: ffff88014a1ce780
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853849] R13: ffff88021fefc000
>>>> R14: ffff88021fef9000 R15: 0000000000000000
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853870] FS:
>>>> 0000000000000000(0000) GS:ffff8800bf500000(0000)
>>>> knlGS:0000000000000000
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853894] CS:  0010 DS: 0000 ES:
>>>> 0000 CR0: 000000008005003b
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853911] CR2: 0000000001400050
>>>> CR3: 0000000001c27000 CR4: 00000000000006e0
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853932] DR0: 0000000000000000
>>>> DR1: 0000000000000000 DR2: 0000000000000000
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853952] DR3: 0000000000000000
>>>> DR6: 00000000ffff0ff0 DR7: 0000000000000400
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853973] Process btrfs-transacti
>>>> (pid: 11394, threadinfo ffff880129a10000, task ffff880202e4ac40)
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.853999] Stack:
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854006]  ffff880129a11b50
>>>> ffff880000000003 ffff88003c60a098 0000000000000003
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854035]  ffffffffffffffff
>>>> ffffffff810e6aaa 0000000000000000 0000000602e4ac40
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854063]  ffffffff8133e3f0
>>>> ffffffff810e6cee 0000000000001000 0000000000000000
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854092] Call Trace:
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854103]  [<ffffffff810e6aaa>] ?
>>>> cleancache_get_key+0x4a/0x60
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854122]  [<ffffffff8133e3f0>] ?
>>>> btrfs_wake_function+0x0/0x20
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854140]  [<ffffffff810e6cee>] ?
>>>> __cleancache_flush_inode+0x3e/0x70
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854161]  [<ffffffff810b34d2>] ?
>>>> truncate_inode_pages_range+0x42/0x440
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854182]  [<ffffffff812f115e>] ?
>>>> btrfs_search_slot+0x89e/0xa00
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854201]  [<ffffffff810c3a45>] ?
>>>> unmap_mapping_range+0xc5/0x2a0
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854220]  [<ffffffff810b3930>] ?
>>>> truncate_pagecache+0x40/0x70
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854240]  [<ffffffff813458b1>] ?
>>>> btrfs_truncate_free_space_cache+0x81/0xe0
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854261]  [<ffffffff812fce15>] ?
>>>> btrfs_write_dirty_block_groups+0x245/0x500
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854283]  [<ffffffff812fcb6a>] ?
>>>> btrfs_run_delayed_refs+0x1ba/0x220
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854304]  [<ffffffff8130afff>] ?
>>>> commit_cowonly_roots+0xff/0x1d0
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854323]  [<ffffffff8130c583>] ?
>>>> btrfs_commit_transaction+0x363/0x760
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854344]  [<ffffffff81067ea0>] ?
>>>> autoremove_wake_function+0x0/0x30
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854364]  [<ffffffff81305bc3>] ?
>>>> transaction_kthread+0x283/0x2a0
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854383]  [<ffffffff81305940>] ?
>>>> transaction_kthread+0x0/0x2a0
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854401]  [<ffffffff81305940>] ?
>>>> transaction_kthread+0x0/0x2a0
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854420]  [<ffffffff81067a16>] ?
>>>> kthread+0x96/0xa0
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854437]  [<ffffffff81003514>] ?
>>>> kernel_thread_helper+0x4/0x10
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854455]  [<ffffffff81067980>] ?
>>>> kthread+0x0/0xa0
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854471]  [<ffffffff81003510>] ?
>>>> kernel_thread_helper+0x0/0x10
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854488] Code: 55 b8 ff 00 00 00
>>>> 53 48 89 fb 48 83 ec 18 48 8b 6f 10 8b 3a 83 ff 04 0f 86 d5 00 00 00
>>>> 85 c9 0f 95 c1 83 ff 07 0f 86 d5 00 00 00 <48> 8b 45 50 bf 05 00 00 00
>>>> 48 89 06 84 c9 48 8b 85 68 fe ff ff
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854742] RIP  [<ffffffff8133ef1b>]
>>>> btrfs_encode_fh+0x2b/0x120
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854762]  RSP <ffff880129a11b00>
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.854773] CR2: 0000000001400050
>>>> Feb 14 00:39:20 lupus kernel: [ 2951.860906] ---[ end trace
>>>> f831c5ceeaa49287 ]---
>>>>
>>>> in my case I had compress-force with lzo and disk_cache enabled
>>>>
>>>>
>>>> another user of the kernel I'm currently running has had the same
>>>> problem with zcache
>>>> (http://forums.gentoo.org/viewtopic-p-6571799.html#6571799)
>>>>
>>>> (looks like in his case compression and any other fancy additional
>>>> features weren't enabled)
>>>>
>>>>
>>>> changes made by this kernel or patchset to btrfs are from
>>>> * io-less dirty throttling patchset (44 patches)
>>>> * zcache V2 ("[PATCH] staging: zcache: fix memory leak" should be
>>>> applied in both cases)
>>>> * PATCH] fix (latent?) memory corruption in btrfs_encode_fh()
>>>> * btrfs-unstable changes to state of
>>>> 3a90983dbdcb2f4f48c0d771d8e5b4d88f27fae6 (so practically equals btrfs
>>>> from 2.6.38-rc4+)
>>>>
>>>> I haven't tried downgrading to vanilla 2.6.37 with zcache only, yet,
>>>>
>>>> but kind of upgraded btrfs to the latest state of the btrfs-unstable
>>>> repository (http://git.eu.kernel.org/?p=linux/kernel/git/mason/btrfs-unstable.git;a=summary)
>>>> namely 3a90983dbdcb2f4f48c0d771d8e5b4d88f27fae6
>>>>
>>>> this also didn't help and seemed to produce the same error-message
>>>>
>>>> so to summarize:
>>>>
>>>> 1) error message appearing with all 4 patchsets applied changing
>>>> btrfs-code and compress-force=lzo and disk_cache enabled
>>>>
>>>> 2) error message appearing with default mount-options and btrfs from
>>>> 2.6.37 and changes for zcache & io-less dirty throttling patchset
>>>> applied (first 2 patch(sets)) from list)
>>>>
>>>>
>>>> in my case I tried to extract / play back a 1.7 GiB tarball of my
>>>> portage-directory (lots of small files and some tar.bzip2 archives)
>>>> via pbzip2 or 7z when the error happened and the message was shown
>>>>
>>>> Due to KMS sound (webradio streaming) was still running but I couldn't
>>>> continue work (X switching to kernel output) so I did the magic sysrq
>>>> combo (reisub)
>>>>
>>>>
>>>> Does that BUG message ring a bell for anyone ?
>>>>
>>>> (if I should leave out anyone from the CC in the next emails or
>>>> future, please holler - I don't want to spam your inboxes)
>>>>
>>>> Thanks
>>>>
>>>> Matt
>>>>
>>>
>>>
>>> OK,
>>>
>>> here's the output of a kernel -
>>>
>>> staying as close to vanilla (2.6.37) as the current situation allows
>>> (only including some corruption or leak fixes for zram & zcache and
>>> "zram_xvmalloc: 64K page fixes and optimizations" (and 2 reiserfs
>>> fixes)):
>>>
>>> so in total the following patches are included in this new kernel
>>> (2.6.37-zcache):
>>>
>>> zram changes:
>>> 1 zram: Fix sparse warning 'Using plain integer as NULL pointer'
>>> 2 [PATCH] zram: fix data corruption issue
>>> 3 [PATCH 0/7][v2] zram_xvmalloc: 64K page fixes and optimizations
>>>
>>> zcache:
>>> 1 zcache-linux-2.6.37-110205
>>> 2 [PATCH] staging: zcache: fix memory leak
>>> 3 [PATCH] zcache: Fix build error when sysfs is not defined
>>>
>>> reiserfs:
>>> 1 [PATCH] reiserfs: Make sure va_end() is always called after
>>> 2 [patch] reiserfs: potential ERR_PTR dereference
>>>
>>>
>>> the same procedure:
>>>
>>> trying to extract the mentioned portage-tarball:
>>>
>>> time (7z e -so -tbzip2 -mmt=5 /system/portage_backup_022011.tbz2 | tar
>>> -xp -C /usr/gentoo/)
>>>
>>>
>>> this hopefully should make it easier to track down the problem:
>>>
>>>
>>> Feb 14 01:59:59 lupus kernel: [  364.777143] device fsid
>>> 684a4213565dd3fe-ca991821badc2aac devid 1 transid 7
>>> /dev/mapper/portage
>>> Feb 14 01:59:59 lupus kernel: [  364.844994] zcache: created ephemeral
>>> tmem pool, id=2
>>> Feb 14 02:02:49 lupus kernel: [  534.577573] BUG: unable to handle
>>> kernel paging request at 0000000037610050
>>> Feb 14 02:02:49 lupus kernel: [  534.577605] IP: [<ffffffff81338cbb>]
>>> btrfs_encode_fh+0x2b/0x110
>>> Feb 14 02:02:49 lupus kernel: [  534.577630] PGD 0
>>> Feb 14 02:02:49 lupus kernel: [  534.577640] Oops: 0000 [#1] PREEMPT SMP
>>> Feb 14 02:02:49 lupus kernel: [  534.577665] last sysfs file:
>>> /sys/devices/system/cpu/cpu7/cache/index2/shared_cpu_map
>>> Feb 14 02:02:49 lupus kernel: [  534.577693] CPU 5
>>> Feb 14 02:02:49 lupus kernel: [  534.577701] Modules linked in: radeon
>>> ttm drm_kms_helper cfbcopyarea cfbimgblt cfbfillrect ipt_REJECT
>>> ipt_LOG xt_limit xt_tcpudp xt_state nf_nat_irc nf_conntrack_irc
>>> nf_nat_ftp nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_conntrack_ftp
>>> iptable_filter ipt_addrtype xt_DSCP xt_dscp xt_iprange ip_tables
>>> ip6table_filter xt_NFQUEUE xt_owner xt_hashlimit xt_conntrack xt_mark
>>> xt_multiport xt_connmark nf_conntrack xt_string ip6_tables x_tables
>>> it87 hwmon_vid coretemp snd_seq_dummy snd_seq_oss snd_seq_midi_event
>>> snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss snd_hda_codec_hdmi
>>> snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_pcm
>>> snd_timer snd e1000e soundcore i2c_i801 shpchp snd_page_alloc wmi
>>> libphy e1000 scsi_wait_scan sl811_hcd ohci_hcd ssb usb_storage
>>> ehci_hcd [last unloaded: tg3]
>>> Feb 14 02:02:49 lupus kernel: [  534.578114]
>>> Feb 14 02:02:49 lupus kernel: [  534.578124] Pid: 8285, comm: tar Not
>>> tainted 2.6.37-zcache #2 FMP55/ipower G3710
>>> Feb 14 02:02:49 lupus kernel: [  534.578146] RIP:
>>> 0010:[<ffffffff81338cbb>]  [<ffffffff81338cbb>]
>>> btrfs_encode_fh+0x2b/0x110
>>> Feb 14 02:02:49 lupus kernel: [  534.578172] RSP:
>>> 0018:ffff88023ea9dcc8  EFLAGS: 00010246
>>> Feb 14 02:02:49 lupus kernel: [  534.578189] RAX: 00000000000000ff
>>> RBX: ffff8800b8643228 RCX: 0000000000000000
>>> Feb 14 02:02:49 lupus kernel: [  534.578210] RDX: ffff88023ea9dd04
>>> RSI: ffff88023ea9dd38 RDI: 0000000000000006
>>> Feb 14 02:02:49 lupus kernel: [  534.578230] RBP: 0000000037610000
>>> R08: ffffffff81338c90 R09: 0000000000000000
>>> Feb 14 02:02:49 lupus kernel: [  534.578251] R10: 0000000000000019
>>> R11: 0000000000000001 R12: ffff8800b8643380
>>> Feb 14 02:02:49 lupus kernel: [  534.578272] R13: ffff8800b8643258
>>> R14: 00007fff806f1f00 R15: 0000000000000000
>>> Feb 14 02:02:49 lupus kernel: [  534.578293] FS:
>>> 00007f823d7ed700(0000) GS:ffff8800bf540000(0000)
>>> knlGS:0000000000000000
>>> Feb 14 02:02:49 lupus kernel: [  534.578317] CS:  0010 DS: 0000 ES:
>>> 0000 CR0: 0000000080050033
>>> Feb 14 02:02:49 lupus kernel: [  534.578334] CR2: 0000000037610050
>>> CR3: 000000023dcef000 CR4: 00000000000006e0
>>> Feb 14 02:02:49 lupus kernel: [  534.578356] DR0: 0000000000000000
>>> DR1: 0000000000000000 DR2: 0000000000000000
>>> Feb 14 02:02:49 lupus kernel: [  534.578377] DR3: 0000000000000000
>>> DR6: 00000000ffff0ff0 DR7: 0000000000000400
>>> Feb 14 02:02:49 lupus kernel: [  534.578398] Process tar (pid: 8285,
>>> threadinfo ffff88023ea9c000, task ffff88023e8b9d40)
>>> Feb 14 02:02:49 lupus kernel: [  534.578421] Stack:
>>> Feb 14 02:02:49 lupus kernel: [  534.578428]  000000013d096000
>>> ffff88023ed84800 ffff88023ea9c000 0000000000000002
>>> Feb 14 02:02:49 lupus kernel: [  534.578458]  ffffffffffffffff
>>> ffffffff810e3b1a 0000000000000001 000000061e1d5240
>>> Feb 14 02:02:49 lupus kernel: [  534.578486]  fffffffffffffffb
>>> ffffffff810e3d5e ffff88010f383000 0000001ab86cb908
>>> Feb 14 02:02:49 lupus kernel: [  534.578514] Call Trace:
>>> Feb 14 02:02:49 lupus kernel: [  534.578525]  [<ffffffff810e3b1a>] ?
>>> cleancache_get_key+0x4a/0x60
>>> Feb 14 02:02:49 lupus kernel: [  534.578544]  [<ffffffff810e3d5e>] ?
>>> __cleancache_flush_inode+0x3e/0x70
>>> Feb 14 02:02:49 lupus kernel: [  534.578565]  [<ffffffff810b0ed2>] ?
>>> truncate_inode_pages_range+0x42/0x440
>>> Feb 14 02:02:49 lupus kernel: [  534.578586]  [<ffffffff81338451>] ?
>>> btrfs_tree_unlock+0x41/0x50
>>> Feb 14 02:02:49 lupus kernel: [  534.578605]  [<ffffffff812e4ed5>] ?
>>> btrfs_release_path+0x15/0x70
>>> Feb 14 02:02:49 lupus kernel: [  534.578624]  [<ffffffff8130bf29>] ?
>>> btrfs_run_delayed_iputs+0x49/0x120
>>> Feb 14 02:02:49 lupus kernel: [  534.578644]  [<ffffffff813107e7>] ?
>>> btrfs_evict_inode+0x27/0x1e0
>>> Feb 14 02:02:49 lupus kernel: [  534.578663]  [<ffffffff810fc3aa>] ?
>>> evict+0x1a/0xa0
>>> Feb 14 02:02:49 lupus kernel: [  534.578678]  [<ffffffff810fc6bd>] ?
>>> iput+0x1cd/0x2b0
>>> Feb 14 02:02:49 lupus kernel: [  534.578694]  [<ffffffff810f266f>] ?
>>> do_unlinkat+0x12f/0x1d0
>>> Feb 14 02:02:49 lupus kernel: [  534.578712]  [<ffffffff810027bb>] ?
>>> system_call_fastpath+0x16/0x1b
>>> Feb 14 02:02:49 lupus kernel: [  534.578730] Code: 55 b8 ff 00 00 00
>>> 53 48 89 fb 48 83 ec 18 48 8b 6f 10 8b 3a 83 ff 04 0f 86 d5 00 00 00
>>> 85 c9 0f 95 c1 83 ff 07 0f 86 d5 00 00 00 <48> 8b 45 50 bf 05 00 00 00
>>> 48 89 06 84 c9 48 8b 85 68 fe ff ff
>>> Feb 14 02:02:49 lupus kernel: [  534.578986] RIP  [<ffffffff81338cbb>]
>>> btrfs_encode_fh+0x2b/0x110
>>> Feb 14 02:02:49 lupus kernel: [  534.579081]  RSP <ffff88023ea9dcc8>
>>> Feb 14 02:02:49 lupus kernel: [  534.579093] CR2: 0000000037610050
>>> Feb 14 02:02:49 lupus kernel: [  534.587513] ---[ end trace
>>> c596b12e66c0b360 ]---
>>>
>>>
>>> for reference I've pasted it to pastebin.com:
>>>
>>> "2.6.37_zcache_V2.patch"
>>> http://pastebin.com/cVSkwQ6M
>>>
>>>
>>>
>>>
>>>
>>> after the reboot I had forgotten to not mount the btrfs volume and it
>>> threw a similar error-message again and remounted several partitions
>>> read-only (including the system partition)
>>> the partition with btrfs (/usr/gentoo) couldn't be unmounted since the
>>> umount process kind of hang
>>>
>>> so here's the error message after a reboot (might not be accurate or
>>> kind of "skewed" since other patches are included (io-less dirty
>>> throttling, PATCH] fix (latent?) memory corruption in
>>> btrfs_encode_fh() and latest changes for btrfs)) but might help to get
>>> some more evidence:
>>>
>>>
>>> Feb 14 02:05:46 lupus kernel: [   63.922648] device fsid
>>> 684a4213565dd3fe-ca991821badc2aac devid 1 transid 13
>>> /dev/mapper/portage
>>> Feb 14 02:05:46 lupus kernel: [   64.047118] btrfs: unlinked 1 orphans
>>> Feb 14 02:05:46 lupus kernel: [   64.051956] zcache: created ephemeral
>>> tmem pool, id=3
>>> Feb 14 02:05:48 lupus kernel: [   65.801364] hub 2-1:1.0: hub_suspend
>>> Feb 14 02:05:48 lupus kernel: [   65.801376] usb 2-1: unlink
>>> qh256-0001/ffff88023fefd180 start 1 [1/0 us]
>>> Feb 14 02:05:48 lupus kernel: [   65.801559] usb 2-1: usb auto-suspend
>>> Feb 14 02:05:50 lupus kernel: [   67.797929] hub 2-0:1.0: hub_suspend
>>> Feb 14 02:05:50 lupus kernel: [   67.797939] usb usb2: bus auto-suspend
>>> Feb 14 02:05:50 lupus kernel: [   67.797942] ehci_hcd 0000:00:1d.0:
>>> suspend root hub
>>> Feb 14 02:05:52 lupus kernel: [   70.050493] BUG: unable to handle
>>> kernel paging request at 0000030341ed0050
>>> Feb 14 02:05:52 lupus kernel: [   70.050670] IP: [<ffffffff8133ef1b>]
>>> btrfs_encode_fh+0x2b/0x120
>>> Feb 14 02:05:52 lupus kernel: [   70.050807] PGD 0
>>> Feb 14 02:05:52 lupus kernel: [   70.050929] Oops: 0000 [#1] PREEMPT SMP
>>> Feb 14 02:05:52 lupus kernel: [   70.051223] last sysfs file:
>>> /sys/module/pcie_aspm/parameters/policy
>>> Feb 14 02:05:52 lupus kernel: [   70.051365] CPU 6
>>> Feb 14 02:05:52 lupus kernel: [   70.051411] Modules linked in:
>>> ipt_REJECT ipt_LOG xt_limit xt_tcpudp xt_state nf_nat_irc
>>> nf_conntrack_irc nf_nat_ftp nf_nat nf_conntrack_ipv4 nf_defrag_ipv4
>>> nf_conntrack_ftp iptable_filter ipt_addrtype xt_DSCP xt_dscp
>>> xt_iprange ip_tables ip6table_filter xt_NFQUEUE xt_owner xt_hashlimit
>>> xt_conntrack xt_mark xt_multiport xt_connmark nf_conntrack xt_string
>>> ip6_tables x_tables it87 hwmon_vid coretemp snd_seq_dummy snd_seq_oss
>>> snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss
>>> snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec
>>> snd_hwdep snd_pcm snd_timer snd i2c_i801 soundcore wmi shpchp e1000e
>>> snd_page_alloc libphy e1000 scsi_wait_scan sl811_hcd ohci_hcd ssb
>>> usb_storage ehci_hcd [last unloaded: tg3]
>>> Feb 14 02:05:52 lupus kernel: [   70.054694]
>>> Feb 14 02:05:52 lupus kernel: [   70.054776] Pid: 7962, comm: umount
>>> Not tainted 2.6.37-plus_v16_zcache #4 FMP55/ipower G3710
>>> Feb 14 02:05:52 lupus kernel: [   70.054912] RIP:
>>> 0010:[<ffffffff8133ef1b>]  [<ffffffff8133ef1b>]
>>> btrfs_encode_fh+0x2b/0x120
>>> Feb 14 02:05:52 lupus kernel: [   70.055084] RSP:
>>> 0018:ffff88023c77d6f8  EFLAGS: 00010246
>>> Feb 14 02:05:52 lupus kernel: [   70.055173] RAX: 00000000000000ff
>>> RBX: ffff88023cde0168 RCX: 0000000000000000
>>> Feb 14 02:05:52 lupus kernel: [   70.055265] RDX: ffff88023c77d734
>>> RSI: ffff88023c77d768 RDI: 0000000000000006
>>> Feb 14 02:05:52 lupus kernel: [   70.055357] RBP: 0000030341ed0000
>>> R08: ffffffff8133eef0 R09: ffff88023c77d8d8
>>> Feb 14 02:05:52 lupus kernel: [   70.055448] R10: 0000000000000003
>>> R11: 0000000000000001 R12: 00000000ffffffff
>>> Feb 14 02:05:52 lupus kernel: [   70.055540] R13: ffff88023cde0030
>>> R14: ffffea0007dd39f0 R15: 0000000000000001
>>> Feb 14 02:05:52 lupus kernel: [   70.055633] FS:
>>> 00007fb1cad04760(0000) GS:ffff8800bf580000(0000)
>>> knlGS:0000000000000000
>>> Feb 14 02:05:52 lupus kernel: [   70.055762] CS:  0010 DS: 0000 ES:
>>> 0000 CR0: 000000008005003b
>>> Feb 14 02:05:52 lupus kernel: [   70.055851] CR2: 0000030341ed0050
>>> CR3: 000000023c7d5000 CR4: 00000000000006e0
>>> Feb 14 02:05:52 lupus kernel: [   70.055943] DR0: 0000000000000000
>>> DR1: 0000000000000000 DR2: 0000000000000000
>>> Feb 14 02:05:52 lupus kernel: [   70.056035] DR3: 0000000000000000
>>> DR6: 00000000ffff0ff0 DR7: 0000000000000400
>>> Feb 14 02:05:52 lupus kernel: [   70.056128] Process umount (pid:
>>> 7962, threadinfo ffff88023c77c000, task ffff88023c7a4260)
>>> Feb 14 02:05:52 lupus kernel: [   70.056257] Stack:
>>> Feb 14 02:05:52 lupus kernel: [   70.056338]  0000000000000000
>>> 0000000000000002 ffff880200000000 0000000000000003
>>> Feb 14 02:05:52 lupus kernel: [   70.056630]  ffffea0007dd39f0
>>> ffffffff810e6aaa ffff880200000041 0000000600000246
>>> Feb 14 02:05:52 lupus kernel: [   70.056922]  ffff88023cdcd300
>>> ffffffff810e6b3a 0000000000000001 ffffffff8132bb7c
>>> Feb 14 02:05:52 lupus kernel: [   70.057213] Call Trace:
>>> Feb 14 02:05:52 lupus kernel: [   70.057301]  [<ffffffff810e6aaa>] ?
>>> cleancache_get_key+0x4a/0x60
>>> Feb 14 02:05:52 lupus kernel: [   70.057393]  [<ffffffff810e6b3a>] ?
>>> __cleancache_get_page+0x7a/0xd0
>>> Feb 14 02:05:52 lupus kernel: [   70.057487]  [<ffffffff8132bb7c>] ?
>>> merge_state+0x7c/0x150
>>> Feb 14 02:05:52 lupus kernel: [   70.057579]  [<ffffffff8132e4de>] ?
>>> __extent_read_full_page+0x52e/0x710
>>> Feb 14 02:05:52 lupus kernel: [   70.057673]  [<ffffffff813bdea4>] ?
>>> rb_insert_color+0xa4/0x140
>>> Feb 14 02:05:52 lupus kernel: [   70.057766]  [<ffffffff8134b0b6>] ?
>>> tree_insert+0x86/0x1e0
>>> Feb 14 02:05:52 lupus kernel: [   70.057859]  [<ffffffff81058c73>] ?
>>> lock_timer_base.clone.22+0x33/0x70
>>> Feb 14 02:05:52 lupus kernel: [   70.058004]  [<ffffffff81305060>] ?
>>> btree_get_extent+0x0/0x1c0
>>> Feb 14 02:05:52 lupus kernel: [   70.058097]  [<ffffffff81330b21>] ?
>>> read_extent_buffer_pages+0x2d1/0x470
>>> Feb 14 02:05:52 lupus kernel: [   70.058191]  [<ffffffff81305060>] ?
>>> btree_get_extent+0x0/0x1c0
>>> Feb 14 02:05:52 lupus kernel: [   70.058283]  [<ffffffff8130674d>] ?
>>> btree_read_extent_buffer_pages.clone.65+0x4d/0xa0
>>> Feb 14 02:05:52 lupus kernel: [   70.058415]  [<ffffffff813076f9>] ?
>>> read_tree_block+0x39/0x60
>>> Feb 14 02:05:52 lupus kernel: [   70.058508]  [<ffffffff812ed5e6>] ?
>>> read_block_for_search.clone.40+0x116/0x410
>>> Feb 14 02:05:52 lupus kernel: [   70.058638]  [<ffffffff812eb228>] ?
>>> btrfs_cow_block+0x118/0x2b0
>>> Feb 14 02:05:52 lupus kernel: [   70.058731]  [<ffffffff812f0bc7>] ?
>>> btrfs_search_slot+0x307/0xa00
>>> Feb 14 02:05:52 lupus kernel: [   70.058823]  [<ffffffff812f6b18>] ?
>>> lookup_inline_extent_backref+0x98/0x4a0
>>> Feb 14 02:05:52 lupus kernel: [   70.058919]  [<ffffffff810e33d7>] ?
>>> kmem_cache_alloc+0x87/0xa0
>>> Feb 14 02:05:52 lupus kernel: [   70.059032]  [<ffffffff812f891c>] ?
>>> __btrfs_free_extent+0xcc/0x6f0
>>> Feb 14 02:05:52 lupus kernel: [   70.059125]  [<ffffffff812fc4cf>] ?
>>> run_clustered_refs+0x39f/0x880
>>> Feb 14 02:05:52 lupus kernel: [   70.059220]  [<ffffffff810b1f98>] ?
>>> pagevec_lookup_tag+0x18/0x20
>>> Feb 14 02:05:52 lupus kernel: [   70.059312]  [<ffffffff810a7c81>] ?
>>> filemap_fdatawait_range+0x91/0x180
>>> Feb 14 02:05:52 lupus kernel: [   70.059405]  [<ffffffff812fca77>] ?
>>> btrfs_run_delayed_refs+0xc7/0x220
>>> Feb 14 02:05:52 lupus kernel: [   70.059498]  [<ffffffff8130c29c>] ?
>>> btrfs_commit_transaction+0x7c/0x760
>>> Feb 14 02:05:52 lupus kernel: [   70.059591]  [<ffffffff81067ea0>] ?
>>> autoremove_wake_function+0x0/0x30
>>> Feb 14 02:05:52 lupus kernel: [   70.059683]  [<ffffffff8130cdef>] ?
>>> start_transaction+0x1bf/0x270
>>> Feb 14 02:05:52 lupus kernel: [   70.059775]  [<ffffffff8110e96a>] ?
>>> __sync_filesystem+0x5a/0x90
>>> Feb 14 02:05:52 lupus kernel: [   70.059867]  [<ffffffff810eae8d>] ?
>>> generic_shutdown_super+0x2d/0x100
>>> Feb 14 02:05:52 lupus kernel: [   70.059960]  [<ffffffff810eafb9>] ?
>>> kill_anon_super+0x9/0x50
>>> Feb 14 02:05:52 lupus kernel: [   70.060051]  [<ffffffff810eb266>] ?
>>> deactivate_locked_super+0x26/0x80
>>> Feb 14 02:05:52 lupus kernel: [   70.060144]  [<ffffffff811043ea>] ?
>>> sys_umount+0x7a/0x390
>>> Feb 14 02:05:52 lupus kernel: [   70.060235]  [<ffffffff810027bb>] ?
>>> system_call_fastpath+0x16/0x1b
>>> Feb 14 02:05:52 lupus kernel: [   70.060325] Code: 55 b8 ff 00 00 00
>>> 53 48 89 fb 48 83 ec 18 48 8b 6f 10 8b 3a 83 ff 04 0f 86 d5 00 00 00
>>> 85 c9 0f 95 c1 83 ff 07 0f 86 d5 00 00 00 <48> 8b 45 50 bf 05 00 00 00
>>> 48 89 06 84 c9 48 8b 85 68 fe ff ff
>>> Feb 14 02:05:52 lupus kernel: [   70.063170] RIP  [<ffffffff8133ef1b>]
>>> btrfs_encode_fh+0x2b/0x120
>>> Feb 14 02:05:52 lupus kernel: [   70.063302]  RSP <ffff88023c77d6f8>
>>> Feb 14 02:05:52 lupus kernel: [   70.063386] CR2: 0000030341ed0050
>>> Feb 14 02:05:52 lupus kernel: [   70.063528] ---[ end trace
>>> 3313552d105b1535 ]---
>>> Feb 14 02:06:16 lupus kernel: [   93.961960] BUG: unable to handle
>>> kernel paging request at 0000030341ed0050
>>> Feb 14 02:06:16 lupus kernel: [   93.962171] IP: [<ffffffff8133ef1b>]
>>> btrfs_encode_fh+0x2b/0x120
>>> Feb 14 02:06:16 lupus kernel: [   93.962307] PGD 0
>>> Feb 14 02:06:16 lupus kernel: [   93.962430] Oops: 0000 [#2] PREEMPT SMP
>>> Feb 14 02:06:16 lupus kernel: [   93.962637] last sysfs file:
>>> /sys/devices/system/cpu/cpu7/cache/index2/shared_cpu_map
>>> Feb 14 02:06:16 lupus kernel: [   93.962766] CPU 5
>>> Feb 14 02:06:16 lupus kernel: [   93.962812] Modules linked in:
>>> ipt_REJECT ipt_LOG xt_limit xt_tcpudp xt_state nf_nat_irc
>>> nf_conntrack_irc nf_nat_ftp nf_nat nf_conntrack_ipv4 nf_defrag_ipv4
>>> nf_conntrack_ftp iptable_filter ipt_addrtype xt_DSCP xt_dscp
>>> xt_iprange ip_tables ip6table_filter xt_NFQUEUE xt_owner xt_hashlimit
>>> xt_conntrack xt_mark xt_multiport xt_connmark nf_conntrack xt_string
>>> ip6_tables x_tables it87 hwmon_vid coretemp snd_seq_dummy snd_seq_oss
>>> snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss
>>> snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec
>>> snd_hwdep snd_pcm snd_timer snd i2c_i801 soundcore wmi shpchp e1000e
>>> snd_page_alloc libphy e1000 scsi_wait_scan sl811_hcd ohci_hcd ssb
>>> usb_storage ehci_hcd [last unloaded: tg3]
>>> Feb 14 02:06:16 lupus kernel: [   93.966044]
>>> Feb 14 02:06:16 lupus kernel: [   93.966127] Pid: 7915, comm:
>>> btrfs-transacti Tainted: G      D     2.6.37-plus_v16_zcache #4
>>> FMP55/ipower G3710
>>> Feb 14 02:06:16 lupus kernel: [   93.966266] RIP:
>>> 0010:[<ffffffff8133ef1b>]  [<ffffffff8133ef1b>]
>>> btrfs_encode_fh+0x2b/0x120
>>> Feb 14 02:06:16 lupus kernel: [   93.966440] RSP:
>>> 0018:ffff88023c63b6e0  EFLAGS: 00010246
>>> Feb 14 02:06:16 lupus kernel: [   93.966528] RAX: 00000000000000ff
>>> RBX: ffff88023cde0168 RCX: 0000000000000000
>>> Feb 14 02:06:16 lupus kernel: [   93.966620] RDX: ffff88023c63b71c
>>> RSI: ffff88023c63b750 RDI: 0000000000000006
>>> Feb 14 02:06:16 lupus kernel: [   93.966713] RBP: 0000030341ed0000
>>> R08: ffffffff8133eef0 R09: ffff88023c63b8c0
>>> Feb 14 02:06:16 lupus kernel: [   93.966805] R10: 0000000000000003
>>> R11: 0000000000000001 R12: 00000000ffffffff
>>> Feb 14 02:06:16 lupus kernel: [   93.966897] R13: ffff88023cde0030
>>> R14: ffffea0007d59bc8 R15: 0000000000000001
>>> Feb 14 02:06:16 lupus kernel: [   93.966990] FS:
>>> 0000000000000000(0000) GS:ffff8800bf540000(0000)
>>> knlGS:0000000000000000
>>> Feb 14 02:06:16 lupus kernel: [   93.967120] CS:  0010 DS: 0000 ES:
>>> 0000 CR0: 000000008005003b
>>> Feb 14 02:06:16 lupus kernel: [   93.967209] CR2: 0000030341ed0050
>>> CR3: 0000000001c27000 CR4: 00000000000006e0
>>> Feb 14 02:06:16 lupus kernel: [   93.967302] DR0: 0000000000000000
>>> DR1: 0000000000000000 DR2: 0000000000000000
>>> Feb 14 02:06:16 lupus kernel: [   93.967394] DR3: 0000000000000000
>>> DR6: 00000000ffff0ff0 DR7: 0000000000000400
>>> Feb 14 02:06:16 lupus kernel: [   93.967500] Process btrfs-transacti
>>> (pid: 7915, threadinfo ffff88023c63a000, task ffff88023c7a1620)
>>> Feb 14 02:06:16 lupus kernel: [   93.967630] Stack:
>>> Feb 14 02:06:16 lupus kernel: [   93.967711]  0000000000000000
>>> 0000000000000002 0000000000000000 0000000000000003
>>> Feb 14 02:06:16 lupus kernel: [   93.968057]  ffffea0007d59bc8
>>> ffffffff810e6aaa 0000000000000041 0000000600000002
>>> Feb 14 02:06:16 lupus kernel: [   93.968348]  0000000000000000
>>> ffffffff810e6b3a 0000000000000001 ffffffff00000001
>>> Feb 14 02:06:16 lupus kernel: [   93.968639] Call Trace:
>>> Feb 14 02:06:16 lupus kernel: [   93.968728]  [<ffffffff810e6aaa>] ?
>>> cleancache_get_key+0x4a/0x60
>>> Feb 14 02:06:16 lupus kernel: [   93.968820]  [<ffffffff810e6b3a>] ?
>>> __cleancache_get_page+0x7a/0xd0
>>> Feb 14 02:06:16 lupus kernel: [   93.968914]  [<ffffffff8132e4de>] ?
>>> __extent_read_full_page+0x52e/0x710
>>> Feb 14 02:06:16 lupus kernel: [   93.969008]  [<ffffffff812f3f93>] ?
>>> update_reserved_bytes+0xb3/0x140
>>> Feb 14 02:06:16 lupus kernel: [   93.969102]  [<ffffffff81305060>] ?
>>> btree_get_extent+0x0/0x1c0
>>> Feb 14 02:06:16 lupus kernel: [   93.969193]  [<ffffffff8132bb7c>] ?
>>> merge_state+0x7c/0x150
>>> Feb 14 02:06:16 lupus kernel: [   93.969285]  [<ffffffff81330b21>] ?
>>> read_extent_buffer_pages+0x2d1/0x470
>>> Feb 14 02:06:16 lupus kernel: [   93.969378]  [<ffffffff81305060>] ?
>>> btree_get_extent+0x0/0x1c0
>>> Feb 14 02:06:16 lupus kernel: [   93.969470]  [<ffffffff8130674d>] ?
>>> btree_read_extent_buffer_pages.clone.65+0x4d/0xa0
>>> Feb 14 02:06:16 lupus kernel: [   93.969602]  [<ffffffff813076f9>] ?
>>> read_tree_block+0x39/0x60
>>> Feb 14 02:06:16 lupus kernel: [   93.969694]  [<ffffffff812ed5e6>] ?
>>> read_block_for_search.clone.40+0x116/0x410
>>> Feb 14 02:06:16 lupus kernel: [   93.969878]  [<ffffffff812f0bc7>] ?
>>> btrfs_search_slot+0x307/0xa00
>>> Feb 14 02:06:16 lupus kernel: [   93.969970]  [<ffffffff812f6b18>] ?
>>> lookup_inline_extent_backref+0x98/0x4a0
>>> Feb 14 02:06:16 lupus kernel: [   93.970065]  [<ffffffff810e33d7>] ?
>>> kmem_cache_alloc+0x87/0xa0
>>> Feb 14 02:06:16 lupus kernel: [   93.970157]  [<ffffffff812f891c>] ?
>>> __btrfs_free_extent+0xcc/0x6f0
>>> Feb 14 02:06:16 lupus kernel: [   93.970249]  [<ffffffff812f8434>] ?
>>> update_block_group.clone.62+0xc4/0x280
>>> Feb 14 02:06:16 lupus kernel: [   93.970343]  [<ffffffff812fc4cf>] ?
>>> run_clustered_refs+0x39f/0x880
>>> Feb 14 02:06:16 lupus kernel: [   93.970436]  [<ffffffff812fca77>] ?
>>> btrfs_run_delayed_refs+0xc7/0x220
>>> Feb 14 02:06:16 lupus kernel: [   93.970529]  [<ffffffff810e15f9>] ?
>>> new_slab+0x169/0x1f0
>>> Feb 14 02:06:16 lupus kernel: [   93.970619]  [<ffffffff8130c29c>] ?
>>> btrfs_commit_transaction+0x7c/0x760
>>> Feb 14 02:06:16 lupus kernel: [   93.970713]  [<ffffffff81067ea0>] ?
>>> autoremove_wake_function+0x0/0x30
>>> Feb 14 02:06:16 lupus kernel: [   93.970806]  [<ffffffff81305bc3>] ?
>>> transaction_kthread+0x283/0x2a0
>>> Feb 14 02:06:16 lupus kernel: [   93.970898]  [<ffffffff81305940>] ?
>>> transaction_kthread+0x0/0x2a0
>>> Feb 14 02:06:16 lupus kernel: [   93.970990]  [<ffffffff81305940>] ?
>>> transaction_kthread+0x0/0x2a0
>>> Feb 14 02:06:16 lupus kernel: [   93.971083]  [<ffffffff81067a16>] ?
>>> kthread+0x96/0xa0
>>> Feb 14 02:06:16 lupus kernel: [   93.971174]  [<ffffffff81003514>] ?
>>> kernel_thread_helper+0x4/0x10
>>> Feb 14 02:06:16 lupus kernel: [   93.971266]  [<ffffffff81067980>] ?
>>> kthread+0x0/0xa0
>>> Feb 14 02:06:16 lupus kernel: [   93.971355]  [<ffffffff81003510>] ?
>>> kernel_thread_helper+0x0/0x10
>>> Feb 14 02:06:16 lupus kernel: [   93.971444] Code: 55 b8 ff 00 00 00
>>> 53 48 89 fb 48 83 ec 18 48 8b 6f 10 8b 3a 83 ff 04 0f 86 d5 00 00 00
>>> 85 c9 0f 95 c1 83 ff 07 0f 86 d5 00 00 00 <48> 8b 45 50 bf 05 00 00 00
>>> 48 89 06 84 c9 48 8b 85 68 fe ff ff
>>> Feb 14 02:06:16 lupus kernel: [   93.974280] RIP  [<ffffffff8133ef1b>]
>>> btrfs_encode_fh+0x2b/0x120
>>> Feb 14 02:06:16 lupus kernel: [   93.974412]  RSP <ffff88023c63b6e0>
>>> Feb 14 02:06:16 lupus kernel: [   93.974497] CR2: 0000030341ed0050
>>> Feb 14 02:06:16 lupus kernel: [   93.974599] ---[ end trace
>>> 3313552d105b1536 ]---
>>> Feb 14 02:07:04 lupus kernel: [  141.906124] zcache: destroyed pool id=2
>>> Feb 14 02:07:17 lupus kernel: [  154.783358] SysRq : Keyboard mode set
>>> to system default
>>> Feb 14 02:07:18 lupus kernel: [  155.486147] SysRq : Terminate All Tasks
>>>
>>>
>>> That's all for now
>>>
>>> Thanks & Regards
>>>
>>> Matt
>>>
>>
>> (leaving out several folks from the CC to avoid spamming - if I left
>> out someone wrongfully please re-add)
>>
>> running an addr2line reveals:
>>
>>
>> addr2line -e /usr/src/linux-2.6.37_vanilla/vmlinux -i ffffffff81338cbb
>> export.c:0
>>
>>
>> hope that helps
>>
>>
>> Regards
>>
>> Matt
>>
>
>
> ok, maybe it's useful to have some more details how to reproduce it as
> easily as possible and about my configuration:
>
> preparation steps:
>
> 1) 2.6.37 vanilla kernel with the mentioned changes to zram (and
> xvmalloc), zcache (+ fixes)
>
> configuration specifics:
>
> CONFIG_CRYPTO_PCRYPT=y
>
> 2) on a non-btrfs partition or with zcache disable: get a
> portage-tarball comparable to mine download from one of the
> gentoo-mirrors (http://www.gentoo.org/main/en/mirrors2.xml), e.g. the
> University of California:
> ftp://ftp.ucsb.edu/pub/mirrors/linux/gentoo/snapshots/
>
> (weighing only around 40 MiB) then
>
> get that tarball to a decent size by adding the latest changes from a
> rsync-mirror (http://www.gentoo.org/main/en/mirrors-rsync.xml)
>
> I can also upload my specific tarball weighing at 1.7 GiB at request -
> just point me a place to drop it
>
> 3) creating a tar.bzip2 ball (preferably via 7z or pbzip2 so that it
> can be extracted later in parallel to create some pressure)
>
>
> Hardware:
> core i7 860 (4 cores - ht -> 8 threads), 8 GiB of RAM,
> underlying harddrive is a Samsung HD203WI, NCQ is disabled
> (queue_depth set to "1"), using CFQ as i/o scheduler
>
> echo "13" > /proc/sys/vm/page-cluster
> echo "60" > /proc/sys/vm/swappiness
> echo "3000" > /proc/sys/vm/dirty_expire_centisecs
> echo "1500"  > /proc/sys/vm/dirty_writeback_centisecs
> echo "15" > /proc/sys/vm/dirty_background_ratio
> echo "50"   > /proc/sys/vm/dirty_ratio
> echo "50" > /proc/sys/vm/vfs_cache_pressure
> echo "32768" > /proc/sys/vm/min_free_kbytes
>
> for i in /sys/block/sd*; do
>         /bin/echo "4096" >  $i/queue/read_ahead_kb
>         /bin/echo "64" >  $i/queue/max_sectors_kb
>         /bin/echo "1"   >  $i/queue/rq_affinity
> done
>
> nr_requests is set to "1024"
>
> slice_sync to "150"
> fifo_expire_sync to "50"
>
> echo 4096 > /sys/class/bdi/default/read_ahead_kb
>
>
> steps to get the "result":
>
> 1) cryptsetup-partition with aes or twofish-encryption (512 bits)
> [using cryptsetup 1.1.3* or 1.2*]
>
> 2) on top of that btrfs
>
> 3) extracting the tarball (usually I'm adding a "time" in front to see
> how long it took): time (7z e -so -tbzip2 -mmt=5
> /system/portage_backup_022011.tbz2 | tar
> -xp -C /usr/gentoo/)
>
>
> "result":
>
> 1) it seems to take several seconds or even minutes until that BUG
> message gets shown so maybe some memory (or other kind of subsystem)
> pressure is needed to trigger it
>
>
> I hope that's useful in reproducing the BUG
>
>
> Thanks & Regards
>
> Matt
>

*bump*

adding: Li Zefan, Miao Xie, Yan Zheng, Dan Rosenberg, Josef Bacik and
the btrfs mailing list to CC
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/