From: Chen Gang <gang.chen@asianux.com>
To: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>,
KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
riel@redhat.com, hughd@google.com, xemul@parallels.com,
Wanpeng Li <liwanp@linux.vnet.ibm.com>,
Cyrill Gorcunov <gorcunov@gmail.com>,
linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH v2] mm/shmem.c: check the return value of mpol_to_str()
Date: Wed, 18 Sep 2013 09:37:04 +0800 [thread overview]
Message-ID: <523903C0.6000609@asianux.com> (raw)
In-Reply-To: <alpine.DEB.2.02.1309171552141.21696@chino.kir.corp.google.com>
On 09/18/2013 06:53 AM, David Rientjes wrote:
> On Tue, 17 Sep 2013, Chen Gang wrote:
>
>>> BUG_ON() is safe. but I still don't like it. As far as I heard, Google
>>> changes BUG_ON as nop. So, BUG_ON(mpol_to_str() < 0) breaks google.
>>> Please treat an assertion as assertion. Not any other something.
>>>
>
> Google does not disable BUG_ON(), sheesh.
>
That sounds a good news.
>> Hmm... in kernel wide, BUG_ON() is 'common' 'standard' assertion, and
>> "mm/" is a common sub-system (not architecture specific), so when we
>> use BUG_ON(), we already 'express' our 'opinion' enough to readers.
>>
>
> That's ridiculous, we're not going to panic the kernel at runtime because
> a buffer is too small. Make it a compile-time error like I suggested so
> we catch this before we even build the kernel.
>
It seems not quite polite? ;-)
BUG_ON() is widely and commonly used in kernel wide, and BUG_ON() can be
customized by any architectures, so I guess, if google really think it
is necessary, it will customize it.
If "compile-time error" will make code complex to both readers and
writers (e.g. our case), forcing "compile-time error" may still be good
enough to google, but may not be good enough for others.
So in my opinion, for our case which is a common sub-system, not an
architecture specific sub-system, better use "run-time error".
Thanks.
--
Chen Gang
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2013-09-18 1:38 UTC|newest]
Thread overview: 92+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-20 3:56 [PATCH 0/3] mm: mempolicy: the failure processing about mpol_to_str() Chen Gang
2013-08-20 3:56 ` Chen Gang
2013-08-20 3:57 ` [PATCH 1/3] mm/mempolicy.c: still fill buffer as full as possible when buffer space is not enough in mpol_to_str() Chen Gang
2013-08-20 3:57 ` Chen Gang
2013-08-20 3:58 ` [PATCH 2/3] fs/proc/task_mmu.c: check the return value of mpol_to_str() Chen Gang
2013-08-20 3:58 ` Chen Gang
2013-08-20 3:59 ` [PATCH 3/3] mm/shmem.c: " Chen Gang
2013-08-20 3:59 ` Chen Gang
2013-08-20 5:30 ` [PATCH 0/3] mm: mempolicy: the failure processing about mpol_to_str() Cyrill Gorcunov
2013-08-20 5:30 ` Cyrill Gorcunov
2013-08-20 5:41 ` Chen Gang
2013-08-20 5:41 ` Chen Gang
2013-08-20 6:47 ` Cyrill Gorcunov
2013-08-20 6:47 ` Cyrill Gorcunov
2013-08-20 7:48 ` Chen Gang
2013-08-20 7:48 ` Chen Gang
2013-08-20 7:51 ` Chen Gang
2013-08-20 7:51 ` Chen Gang
2013-08-20 8:09 ` Chen Gang
2013-08-20 8:09 ` Chen Gang
2013-08-20 8:13 ` Chen Gang F T
2013-08-20 8:13 ` Chen Gang F T
2013-08-20 8:20 ` Chen Gang
2013-08-20 8:20 ` Chen Gang
2013-08-20 8:25 ` Cyrill Gorcunov
2013-08-20 8:25 ` Cyrill Gorcunov
2013-08-20 8:31 ` Chen Gang
2013-08-20 8:31 ` Chen Gang
2013-08-21 2:21 ` [PATCH 0/3] mm: shmem: check the return value of mpol_to_str() Chen Gang
2013-08-21 2:21 ` Chen Gang
2013-08-21 2:22 ` [PATCH 1/3] fs/proc/task_mmu.c: " Chen Gang
2013-08-21 2:22 ` Chen Gang
2013-08-21 2:23 ` [PATCH 2/3] mm/shmem.c: let shmem_show_mpol() return value Chen Gang
2013-08-21 2:23 ` Chen Gang
2013-08-21 2:24 ` [PATCH 3/3] mm/shmem.c: check the return value of mpol_to_str() Chen Gang
2013-08-21 2:24 ` Chen Gang
2013-08-21 22:03 ` [PATCH 2/3] mm/shmem.c: let shmem_show_mpol() return value Andrew Morton
2013-08-21 22:03 ` Andrew Morton
2013-08-22 0:52 ` Chen Gang
2013-08-22 0:52 ` Chen Gang
2013-08-22 1:04 ` [PATCH] mm/shmem.c: check the return value of mpol_to_str() Chen Gang
2013-08-22 1:04 ` Chen Gang
2013-09-03 5:32 ` Chen Gang
2013-09-03 5:32 ` Chen Gang
2013-09-05 0:24 ` [PATCH v2] " Chen Gang
2013-09-09 20:30 ` David Rientjes
2013-09-10 0:47 ` Chen Gang
2013-09-10 6:43 ` David Rientjes
2013-09-10 7:01 ` Chen Gang
2013-09-12 0:33 ` David Rientjes
2013-09-12 2:19 ` KOSAKI Motohiro
2013-09-12 3:13 ` Chen Gang
2013-09-13 21:12 ` David Rientjes
2013-09-14 2:51 ` KOSAKI Motohiro
2013-09-16 3:27 ` Chen Gang
2013-09-16 20:13 ` David Rientjes
2013-09-17 0:45 ` Chen Gang
2013-09-17 22:51 ` David Rientjes
2013-09-18 1:20 ` Chen Gang
2013-09-12 3:02 ` Chen Gang
2013-09-12 18:19 ` KOSAKI Motohiro
2013-09-13 2:23 ` Chen Gang
2013-09-13 16:50 ` KOSAKI Motohiro
2013-09-16 2:55 ` Chen Gang
2013-09-16 16:16 ` KOSAKI Motohiro
2013-09-17 1:10 ` Chen Gang
2013-09-17 22:53 ` David Rientjes
2013-09-18 1:37 ` Chen Gang [this message]
2013-09-18 22:17 ` David Rientjes
2013-09-13 21:14 ` David Rientjes
2013-09-16 3:17 ` Chen Gang
2013-09-25 2:58 ` [patch] mm, mempolicy: make mpol_to_str robust and always succeed David Rientjes
2013-09-25 2:58 ` David Rientjes
2013-09-25 3:11 ` Dave Jones
2013-09-25 3:11 ` Dave Jones
2013-09-25 3:18 ` David Rientjes
2013-09-25 3:18 ` David Rientjes
2013-09-25 3:25 ` Dave Jones
2013-09-25 3:25 ` Dave Jones
2013-09-25 17:58 ` David Rientjes
2013-09-25 17:58 ` David Rientjes
2013-09-25 21:30 ` Andrew Morton
2013-09-25 21:30 ` Andrew Morton
2013-09-25 22:06 ` David Rientjes
2013-09-25 22:06 ` David Rientjes
2013-08-21 5:31 ` [PATCH 0/3] mm: shmem: check the return value of mpol_to_str() Cyrill Gorcunov
2013-08-21 5:31 ` Cyrill Gorcunov
2013-08-21 5:48 ` Chen Gang
2013-08-21 5:48 ` Chen Gang
-- strict thread matches above, loose matches on Subject: below --
2013-09-19 0:31 [PATCH v2] mm/shmem.c: " Chen,Gang( 陈刚)
[not found] <20130919003142.B72EC1840296@intranet.asianux.com>
2013-09-23 21:46 ` David Rientjes
2013-09-24 2:28 ` Chen Gang
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=523903C0.6000609@asianux.com \
--to=gang.chen@asianux.com \
--cc=akpm@linux-foundation.org \
--cc=gorcunov@gmail.com \
--cc=hughd@google.com \
--cc=kosaki.motohiro@gmail.com \
--cc=kosaki.motohiro@jp.fujitsu.com \
--cc=linux-mm@kvack.org \
--cc=liwanp@linux.vnet.ibm.com \
--cc=riel@redhat.com \
--cc=rientjes@google.com \
--cc=xemul@parallels.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 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.