linux-kernel - Re: [Patch v2] skbuff: Hide GFP_ATOMIC page allocation failures for dropped packets

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <51A4D4AD.2010507@candelatech.com>
Date:	Tue, 28 May 2013 09:00:45 -0700
From:	Ben Greear <greearb@...delatech.com>
To:	Francois Romieu <romieu@...zoreil.com>
CC:	atomlin@...hat.com, netdev@...r.kernel.org, davem@...emloft.net,
	edumazet@...gle.com, pshelar@...ira.com, mst@...hat.com,
	alexander.h.duyck@...el.com, riel@...hat.com, aquini@...hat.com,
	sergei.shtylyov@...entembedded.com, linux-kernel@...r.kernel.org
Subject: Re: [Patch v2] skbuff: Hide GFP_ATOMIC page allocation failures for
 dropped packets

On 05/27/2013 03:41 PM, Francois Romieu wrote:
> atomlin@...hat.com <atomlin@...hat.com> :
> [...]
>> Failed GFP_ATOMIC allocations by the network stack result in dropped
>> packets, which will be received on a subsequent retransmit, and an
>> unnecessary, noisy warning with a kernel backtrace.
>>
>> These warnings are harmless, but they still cause users to panic and
>> file bug reports over dropped packets. It would be better to hide the
>> failed allocation warnings and backtraces, and let retransmits handle
>> dropped packets quietly.
>
> Linux VM may be perfect but device drivers do stupid things.
>
> Please don't paper over it just because some shit ends in your backyard.

We should rate-limit these messages at least.  When a system is low on memory
the logs can quickly fill up with useless OOM messages, further slowing
the system...

Ben

>


-- 
Ben Greear <greearb@...delatech.com>
Candela Technologies Inc  http://www.candelatech.com

--
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/