linux-kernel - Re: [Regression] 3.15 mmc related ext4 corruption with qemu-system-arm

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:	Fri, 13 Jun 2014 13:35:36 +0200
From:	Ulf Hansson <ulf.hansson@...aro.org>
To:	Peter Maydell <peter.maydell@...aro.org>
Cc:	John Stultz <john.stultz@...aro.org>,
	Chris Ball <chris@...ntf.net>,
	Johan Rudholm <jrudholm@...il.com>,
	Russell King - ARM Linux <linux@....linux.org.uk>,
	"Theodore Ts'o" <tytso@....edu>,
	lkml <linux-kernel@...r.kernel.org>
Subject: Re: [Regression] 3.15 mmc related ext4 corruption with qemu-system-arm

On 12 June 2014 14:15, Peter Maydell <peter.maydell@...aro.org> wrote:
> On 12 June 2014 13:09, Ulf Hansson <ulf.hansson@...aro.org> wrote:
>> A simple fix; for the arm_variant, go back to use the old behaviour.
>>
>> A quite simple fix; Invent a new primecell-periphid and a new
>> corresponding variant and use the old behaviour for this variant. The
>> new primecell-periphid then needs to be provided through DT for the
>> QEMU dtb.
>>
>> Is there any of the above solution you see as the preferred one?
>
> Those both sound like workarounds, not fixes, to me. Somebody
> needs to identify whether the bug here is in:
>  * the kernel (unlikely, but possibly the kernel has a race
>    condition that only gets triggered by QEMU's "operations
>    that take time in h/w happen instantaneously in emulation"
>    behaviour)
>  * the QEMU model of the PL181
>  * the QEMU model of the SD card
> and then fix whichever of these is not conforming to the
> specs/docs/etc.

You are right. But...

Since we (or actually me) have made the ARM model to break (it worked
nicely before), I just wanted to restore the behaviour as a quick fix.
I believe going into this in detail can take some more time,
especially if it's related to the ARM model, right!?

Kind regards
Uffe

>
> Also, there's no such thing as a "QEMU dtb", at least for
> most of our board models. QEMU models the actual hardware
> (sometimes buggily or incompletely) and so should use the
> exact same dtb you would use with the hardware.
>
> thanks
> -- PMM
--
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/