linux-kernel - Re: [PATCH 1/2] ARC: show_regs: avoid page allocator

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: <C2D7FE5348E1B147BCA15975FBA23075014642386D@US01WEMBX2.internal.synopsys.com>
Date:   Thu, 20 Dec 2018 18:38:26 +0000
From:   Vineet Gupta <vineet.gupta1@...opsys.com>
To:     Michal Hocko <mhocko@...nel.org>
CC:     "linux-snps-arc@...ts.infradead.org" 
        <linux-snps-arc@...ts.infradead.org>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-arch@...r.kernel.org" <linux-arch@...r.kernel.org>,
        Peter Zijlstra <peterz@...radead.org>
Subject: Re: [PATCH 1/2] ARC: show_regs: avoid page allocator

On 12/20/18 4:57 AM, Michal Hocko wrote:
>> Despite this, lockdep still barfs (see next change), but this patch
>> still has merit as in we use smaller/localized buffers now and there's
>> less instructoh trace to sift thru when debugging pesky issues.
> But show_regs is called from contexts which might be called from deep
> call chains (e.g WARN). Is it safe to allocate such a large stack there?

ARC has 8K pages and 256 additional bytes of stack usage doesn't seem absurdly
high to me !

-Vineet