linux-kernel - Re: [PATCH] mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON

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] [day] [month] [year] [list]

Message-ID: <52BE0AE6.5000208@oracle.com>
Date:	Fri, 27 Dec 2013 18:19:02 -0500
From:	Sasha Levin <sasha.levin@...cle.com>
To:	akpm@...ux-foundation.org
CC:	linux-mm@...ck.org, linux-kernel@...r.kernel.org,
	Sasha Levin <sasha.levin@...cle.com>
Subject: Re: [PATCH] mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE

On 12/26/2013 10:20 PM, Sasha Levin wrote:
> Most of the VM_BUG_ON assertions are performed on a page. Usually, when
> one of these assertions fails we'll get a BUG_ON with a call stack and
> the registers.
>
> I've recently noticed based on the requests to add a small piece of code
> that dumps the page to various VM_BUG_ON sites that the page dump is quite
> useful to people debugging issues in mm.
>
> This patch adds a VM_BUG_ON_PAGE(cond, page) which beyond doing what
> VM_BUG_ON() does, also dumps the page before executing the actual BUG_ON.

Somewhat related to that, I've tried adding a VM_BUG_ON_PAGE in SetPageXXX()
and ClearPageXXX macros to catch cases where page flags are being set or
cleared twice.

There seems to be a lot of those...

Is that a valid use? Or should it be fixed?


Thanks,
Sasha
--
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/