linux-kernel - Re: shmem_getpage_gfp VM_BUG

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]

Date:	Thu, 25 Oct 2012 14:28:59 -0700 (PDT)
From:	Hugh Dickins <hughd@...gle.com>
To:	Dave Jones <davej@...hat.com>, Hugh Dickins <hughd@...gle.com>,
	linux-mm@...ck.org, linux-kernel@...r.kernel.org
Subject: Re: shmem_getpage_gfp VM_BUG_ON triggered. [3.7rc2]

On Thu, 25 Oct 2012, Dave Jones wrote:
> On Wed, Oct 24, 2012 at 09:36:27PM -0700, Hugh Dickins wrote:
> 
>  > Clutching at straws, I expect this is entirely irrelevant, but:
>  > there isn't a warning on line 1151 of mm/shmem.c in 3.7.0-rc2 nor
>  > in current linux.git; rather, there's a VM_BUG_ON on line 1149.
>  > 
>  > So you've inserted a couple of lines for some reason (more useful
>  > trinity behaviour, perhaps)? 
> 
> detritus from the recent mpol_to_str bug that I was chasing.
> Shouldn't be relevant...
> 
>  > And have some config option I'm
>  > unfamiliar with, that mutates a BUG_ON or VM_BUG_ON into a warning?
> 
> Yes, I do have this..
> 
> -#define VM_BUG_ON(cond) BUG_ON(cond)
> +#define VM_BUG_ON(cond) WARN_ON(cond)
> 
> because I got tired of things not going over my usb serial port when I hit them
> a while ago. BUG_ON is pretty unfriendly to bug finding.

Makes sense, thanks for the reassurance.

Hugh
--
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/