public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Jens Axboe <axboe@kernel.dk>
To: Ming Lei <ming.lei@redhat.com>, Guenter Roeck <linux@roeck-us.net>
Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
	Chris Mason <clm@fb.com>
Subject: Re: [PATCH] block: fix splitting segments
Date: Tue, 7 Jan 2020 15:32:58 -0700	[thread overview]
Message-ID: <25ce5140-ee29-c32c-7f5e-b8c6da5c7e90@kernel.dk> (raw)
In-Reply-To: <20200107223035.GA7505@ming.t460p>

On 1/7/20 3:30 PM, Ming Lei wrote:
> On Tue, Jan 07, 2020 at 10:11:45AM -0800, Guenter Roeck wrote:
>> On Tue, Jan 07, 2020 at 11:23:39PM +0800, Ming Lei wrote:
>>> On Tue, Jan 07, 2020 at 04:47:08AM -0800, Guenter Roeck wrote:
>>>> Hi,
>>>>
>>>> On Sun, Dec 29, 2019 at 10:32:30AM +0800, Ming Lei wrote:
>>>>> There are two issues in get_max_segment_size():
>>>>>
>>>>> 1) the default segment boudary mask is bypassed, and some devices still
>>>>> require segment to not cross the default 4G boundary
>>>>>
>>>>> 2) the segment start address isn't taken into account when checking
>>>>> segment boundary limit
>>>>>
>>>>> Fixes the two issues.
>>>>>
>>>>> Fixes: dcebd755926b ("block: use bio_for_each_bvec() to compute multi-page bvec count")
>>>>> Signed-off-by: Ming Lei <ming.lei@redhat.com>
>>>>
>>>> This patch, pushed into mainline as "block: fix splitting segments on
>>>> boundary masks", results in the following crash when booting 'versatilepb'
>>>> in qemu from disk. Bisect log is attached. Detailed log is at
>>>> https://kerneltests.org/builders/qemu-arm-master/builds/1410/steps/qemubuildcommand/logs/stdio
>>>>
>>>> Guenter
>>>>
>>>> ---
>>>> Crash:
>>>>
>>>> kernel BUG at block/bio.c:1885!
>>>> Internal error: Oops - BUG: 0 [#1] ARM
>>>
>>> Please apply the following debug patch, and post the log.
>>>
>>
>> Here you are:
>>
>> max_sectors 2560 max_segs 96 max_seg_size 65536 mask ffffffff
>> c738da80: 8c80/0 2416 28672, 0
>>          total sectors 56
>>
>> (I replaced %p with %px).
>>
> 
> Please try the following patch and see if it makes a difference.
> If not, replace trace_printk with printk in previous debug patch,
> and apply the debug patch only & post the log.

If it is a 32-bit issue, then we should use a 64-bit type to make
this nicer than ULL. But it seems reasonable that it could be!

-- 
Jens Axboe


  reply	other threads:[~2020-01-07 22:33 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20191229023230.28940-1-ming.lei@redhat.com>
2020-01-07 12:47 ` [PATCH] block: fix splitting segments Guenter Roeck
2020-01-07 15:23   ` Ming Lei
2020-01-07 18:11     ` Guenter Roeck
2020-01-07 22:30       ` Ming Lei
2020-01-07 22:32         ` Jens Axboe [this message]
2020-01-08  1:59           ` Ming Lei
2020-01-08  2:36             ` Jens Axboe
2020-01-07 23:06         ` Guenter Roeck

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=25ce5140-ee29-c32c-7f5e-b8c6da5c7e90@kernel.dk \
    --to=axboe@kernel.dk \
    --cc=clm@fb.com \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@roeck-us.net \
    --cc=ming.lei@redhat.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