From: Bob Liu <bob.liu@oracle.com>
To: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>, axboe@kernel.dk
Cc: syzbot <syzbot+b48daca8639150bc5e73@syzkaller.appspotmail.com>,
linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
syzkaller-bugs@googlegroups.com
Subject: Re: INFO: task syz-executor can't die for more than 143 seconds. (2)
Date: Mon, 28 Oct 2019 16:51:12 +0800 [thread overview]
Message-ID: <24296ff7-4a5f-2bd9-63c7-07831f7b4d8d@oracle.com> (raw)
In-Reply-To: <3fbc4bb2-a03b-fbfa-4803-47a6d0075ff2@I-love.SAKURA.ne.jp>
On 10/24/19 6:08 PM, Tetsuo Handa wrote:
> On 2019/10/23 16:56, syzbot wrote:
>> Hello,
>>
>> syzbot found the following crash on:
>>
>> HEAD commit: c4b9850b Add linux-next specific files for 20191018
>> git tree: linux-next
>> console output: https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_x_log.txt-3Fx-3D177b3ab0e00000&d=DwICaQ&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=1ktT0U2YS_I8Zz2o-MS1YcCAzWZ6hFGtyTgvVMGM7gI&m=wOlNeKk9puri9Fvxn8bGDrlWHd-4GPMeJ9rb2CVqXaE&s=PZfBliKlYjm16VnyPzu-3i0SgqlbByIB0iI8jVhcGuk&e=
>> kernel config: https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_x_.config-3Fx-3Dc940ef12efcd1ec&d=DwICaQ&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=1ktT0U2YS_I8Zz2o-MS1YcCAzWZ6hFGtyTgvVMGM7gI&m=wOlNeKk9puri9Fvxn8bGDrlWHd-4GPMeJ9rb2CVqXaE&s=z8tV220wKFTQIJH1tSYLUl8ecAnll94C_mFVcHkuTlc&e=
>> dashboard link: https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_bug-3Fextid-3Db48daca8639150bc5e73&d=DwICaQ&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=1ktT0U2YS_I8Zz2o-MS1YcCAzWZ6hFGtyTgvVMGM7gI&m=wOlNeKk9puri9Fvxn8bGDrlWHd-4GPMeJ9rb2CVqXaE&s=VZ2ZdnAqEd_AkXJujidN3EgwscGpUAdsZjuObKjXN-U&e=
>> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
>> syz repro: https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_x_repro.syz-3Fx-3D1356b8ff600000&d=DwICaQ&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=1ktT0U2YS_I8Zz2o-MS1YcCAzWZ6hFGtyTgvVMGM7gI&m=wOlNeKk9puri9Fvxn8bGDrlWHd-4GPMeJ9rb2CVqXaE&s=Q_svUYj2OBYmIJXnResNzOWVUCyjRpxnpun2Cu15S9M&e=
>> C reproducer: https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_x_repro.c-3Fx-3D14f48687600000&d=DwICaQ&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=1ktT0U2YS_I8Zz2o-MS1YcCAzWZ6hFGtyTgvVMGM7gI&m=wOlNeKk9puri9Fvxn8bGDrlWHd-4GPMeJ9rb2CVqXaE&s=FGZNxR7w-rU29MhJxJtno-c_wUXCJHgPC5V1YNp7h58&e=
>
> The reproducer is trying to allocate 64TB of disk space on /dev/nullb0 using fallocate()
> but __blkdev_issue_zero_pages() cannot bail out upon SIGKILL (and therefore cannot
> terminate for minutes). Can we make it killable?
Yeah, I think we can consider add fatal_signal_pending(current) checking in the while() loop..
> I don't know what action is needed
> for undoing this loop...
>
> while (nr_sects != 0) {
> bio = blk_next_bio(bio, __blkdev_sectors_to_bio_pages(nr_sects),
> gfp_mask);
> bio->bi_iter.bi_sector = sector;
> bio_set_dev(bio, bdev);
> bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
>
> while (nr_sects != 0) {
> sz = min((sector_t) PAGE_SIZE, nr_sects << 9);
> bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0);
> nr_sects -= bi_size >> 9;
> sector += bi_size >> 9;
> if (bi_size < sz)
> break;
> }
> cond_resched();
> }
>
next prev parent reply other threads:[~2019-10-28 8:51 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-23 7:56 INFO: task syz-executor can't die for more than 143 seconds. (2) syzbot
2019-10-24 10:08 ` Tetsuo Handa
2019-10-28 8:51 ` Bob Liu [this message]
2019-11-08 11:41 ` [PATCH] block: Bail out iteration functions upon SIGKILL Tetsuo Handa
2019-11-08 18:13 ` Chaitanya Kulkarni
2019-11-08 22:18 ` Chaitanya Kulkarni
2019-11-12 4:05 ` Damien Le Moal
2019-11-12 14:47 ` Tetsuo Handa
2019-11-13 1:54 ` Damien Le Moal
2019-11-13 6:55 ` Ming Lei
2019-11-13 7:11 ` Damien Le Moal
2019-11-13 7:49 ` Ming Lei
2019-11-15 10:05 ` Tetsuo Handa
2019-11-18 0:02 ` Damien Le Moal
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=24296ff7-4a5f-2bd9-63c7-07831f7b4d8d@oracle.com \
--to=bob.liu@oracle.com \
--cc=axboe@kernel.dk \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=penguin-kernel@I-love.SAKURA.ne.jp \
--cc=syzbot+b48daca8639150bc5e73@syzkaller.appspotmail.com \
--cc=syzkaller-bugs@googlegroups.com \
/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).