linux-kernel - Re: "blocked for more than 120 secs" --> a valid situation, how to prevent?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <4C9BEB49.2060208@interlog.com>
Date:	Thu, 23 Sep 2010 20:05:29 -0400
From:	Douglas Gilbert <dgilbert@...erlog.com>
To:	Mark Lord <kernel@...savvy.com>
CC:	Linux Kernel <linux-kernel@...r.kernel.org>,
	IDE/ATA development list <linux-ide@...r.kernel.org>,
	linux-scsi <linux-scsi@...r.kernel.org>
Subject: Re: "blocked for more than 120 secs" --> a valid situation, how to
 prevent?

Mark,
If you issued the SG_IO ioctl with a timeout of at
least 66 minutes (expressed in milliseconds) then
it looks like ata_scsi_queuecmd() has a problem.

The SCSI FORMAT UNIT command can take a long time.
It has an IMMED bit which when set will return
after the command and its parameters have been
received. The progress of the format can then be
polled by other commands. With the IMMED bit clear
the FORMAT UNIT returns when the format completes
(i.e. after an hour or so). Either way, setting the
timeout on the SG_IO ioctl works as expected.

Doug Gilbert


On 10-09-23 07:41 PM, Mark Lord wrote:
> What's the purpose of this stack dump,
> and how can it be prevented in this NORMAL situation??
>
> The command was "hdparm --security-erase NULL /dev/sdb",
> which takes about 66 minutes to complete on this particular drive.
>
> I don't see any obvious way for the task to mark itself
> as needing longer than 120 secs to complete the operation.
>
> Thanks.
>
> [ 1800.373281] INFO: task hdparm:1979 blocked for more than 120 seconds.
> [ 1800.373288] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
> disables this message.
> [ 1800.373294] hdparm D f64a4c00 0 1979 1718 0x00000000
> [ 1800.373303] f3065c38 00200086 c11be0e3 f64a4c00 c1439ac0 c1439ac0
> c1439ac0 c1439ac0
> [ 1800.373317] f571bdb8 c1439ac0 c1439ac0 dbdc5ec7 00000163 dbdb0cfb
> 00000163 f571bb60
> [ 1800.373329] 00000001 f3065d18 7fffffff f571bb60 f3065c64 c1270527
> f684ca50 f684ca50
> [ 1800.373341] Call Trace:
> [ 1800.373355] [<c11be0e3>] ? ata_scsi_queuecmd+0x6a/0x73
> [ 1800.373366] [<c1270527>] schedule_timeout+0x16/0xa5
> [ 1800.373376] [<c111a4a2>] ? __blk_run_queue+0x3d/0x5e
> [ 1800.373383] [<c1118626>] ? elv_insert+0x67/0x18f
> [ 1800.373389] [<c126fd6a>] wait_for_common+0x8a/0xd9
> [ 1800.373399] [<c1028b75>] ? default_wake_function+0x0/0xd
> [ 1800.373406] [<c126fe3a>] wait_for_completion+0x12/0x14
> [ 1800.373413] [<c111d02f>] blk_execute_rq+0x76/0x8f
> [ 1800.373420] [<c111cf1c>] ? blk_end_sync_rq+0x0/0x28
> [ 1800.373428] [<c111cc3f>] ? blk_rq_append_bio+0x14/0x3b
> [ 1800.373434] [<c111ce95>] ? blk_rq_map_user+0x12e/0x1b5
> [ 1800.373442] [<c11201f8>] sg_io+0x269/0x343
> [ 1800.373450] [<c11204be>] scsi_cmd_ioctl+0x1ec/0x396
> [ 1800.373457] [<c11993cf>] ? get_device+0x13/0x18
> [ 1800.373464] [<c11aeabd>] ? sd_open+0x45/0x104
> [ 1800.373472] [<c11aea0e>] sd_ioctl+0x6b/0x8c
> [ 1800.373479] [<c111e2fe>] __blkdev_driver_ioctl+0x66/0x87
> [ 1800.373486] [<c111ebb2>] blkdev_ioctl+0x5fe/0x62c
> [ 1800.373495] [<c1061e3f>] ? filemap_fault+0xb5/0x2fc
> [ 1800.373503] [<c10a7bde>] block_ioctl+0x2a/0x32
> [ 1800.373509] [<c10a7bde>] ? block_ioctl+0x2a/0x32
> [ 1800.373518] [<c109345a>] vfs_ioctl+0x27/0x91
> [ 1800.373524] [<c10a7bb4>] ? block_ioctl+0x0/0x32
> [ 1800.373531] [<c109398d>] do_vfs_ioctl+0x42a/0x45b
> [ 1800.373538] [<c10727b7>] ? handle_mm_fault+0x3d8/0x7c2
> [ 1800.373547] [<c1088e98>] ? fsnotify_modify+0x4f/0x5a
> [ 1800.373555] [<c101b8f9>] ? do_page_fault+0x1e4/0x243
> [ 1800.373562] [<c10939ec>] sys_ioctl+0x2e/0x48
> [ 1800.373570] [<c1002750>] sysenter_do_call+0x12/0x26
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/