linux-kernel - Re: [PATCH] x86: MCE: Fix for mce_panic

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: <20090528081549.GC1065@one.firstfloor.org>
Date:	Thu, 28 May 2009 10:15:49 +0200
From:	Andi Kleen <andi@...stfloor.org>
To:	Hidetoshi Seto <seto.hidetoshi@...fujitsu.com>
Cc:	Andi Kleen <andi@...stfloor.org>, linux-kernel@...r.kernel.org,
	hpa@...or.com, x86@...nel.org, Andi Kleen <ak@...ux.intel.com>
Subject: Re: [PATCH] x86: MCE: Fix for mce_panic_timeout

On Thu, May 28, 2009 at 09:52:55AM +0900, Hidetoshi Seto wrote:
> Andi Kleen wrote:
> > Hidetoshi Seto <seto.hidetoshi@...fujitsu.com> writes:
> >>  - In case of panic_timeout > 0 and mce_bootlog == 0.
> >>    System should reboot after panic, but it doesn't on mce panic because
> >>    current mce code overwrite panic_timeout to 0.
> > 
> > Nope, with bootlog==0 it should _not_ automatically reboot on panic.
> > Automatic rebooting makes mainly sense with boot logging, otherwise
> > you will likely lose the information. Or at least the kernel 
> > cannot know if you lose information or not so it has to err on 
> > the safe side.
> 
> Users already know they might lose the information about the panic
> if panic_timeout > 0.  It is same on all kind of panic.

Yes if they set panic=..., but they don't expect it by default as
this patch does.

> 
> > I changed it now to only override with panic_timeout == 0,
> > as in the user didn't set anything,
> > that's probably the most sensible semantics anyways.
> 
> It's OK with me.
> The logic in this patch also seems good.

Thanks.

> 
> But...
> 
> > v2: Only force panic timeout when it's shorter (H.Seto)
> > v3: Only panic when there is no earlier timeout or it's not zero
> > (based on comment H.Seto)
> 
> "Only panic when ..." ?
> I could not cache the meaning of this changelog.

"Only automatically panic ..."

Ok fair enough, if I ever redo a repost I'll update that line, but I hope
I don't have to touch this trivial patch anymore.

-Andi
-- 
ak@...ux.intel.com -- Speaking for myself only.
--
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/