linux-kernel - Re: [PATCH] libata: Forcing PIO0 mode on reset must not freeze system

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:	Mon, 11 Feb 2008 06:32:06 -0500
From:	Alan Cox <alan@...hat.com>
To:	Tejun Heo <htejun@...il.com>, linux-kernel@...r.kernel.org,
	linux-ide@...r.kernel.org, alan@...hat.com, jeff@...zik.org
Subject: Re: [PATCH] libata: Forcing PIO0 mode on reset must not freeze system

On Mon, Feb 11, 2008 at 11:29:07AM +0100, Holger Macht wrote:
> > In the above example, even the reset sequence itself can cause hang if
> > the hardware is implemented slightly differently.  The reason why
> > set_piomode() locks up but reset sequence doesn't is simple dumb luck.
> 
> Another thing, whether it's poor luck or not, it worked like this than at
> least 2.6.22. And it was _heavily_ tested. The above commit broke it
> between 2.6.24-rc1 and 2.6.24-rc2, which is at least a regression.

Not neccessarily. It may just be timing chance on your box.

I agree however we should be doing the reset after the PIO0 switch if it
turns out that the precise order of the two events matters.

Alan

--
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/