linux-kernel - Re: [PATCH v1] ARM:sa1100: Remove a redundant spin lock

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]

Date:	Wed, 2 Jul 2014 19:02:12 +0800
From:	"Yang,Wei" <Wei.Yang@...driver.com>
To:	Russell King - ARM Linux <linux@....linux.org.uk>
CC:	<mroberto@...i.cetuc.puc-rio.br>, <linux-kernel@...r.kernel.org>,
	<linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH v1] ARM:sa1100: Remove a redundant spin lock

On 07/02/2014 06:19 PM, Russell King - ARM Linux wrote:
> On Wed, Jul 02, 2014 at 05:19:40PM +0800, Yang,Wei wrote:
>> Hi Guys,
>>
>> What about this patch?
> The only concern on the face of it is that it removes mutual exclusion
> from the pci config write path, where a read-modifiy-write operation is
> performed.
>
> However, the PCI code already gives that guarantee (drivers/pci/access.c)
> so this should be safe.
>
> As this is fairly old code, it would be useful to know what the motivation
> is behind this change.  Is it purely clean up, or is it something that
> you've tested, or is this a change that you require for something else?
>
> Thanks.
>
Hmm, I fixed a bug of pci config read/write of an ARM board, but 
unfortunately, so far ML does not support it. So
I cannot send the fix, but I grepped the pci source code of ARM 
architecure, I found that the pci code of a few boards always
define a static spin lock to excluse the pci config read/write path. I 
just intended to clean up them. If you agree the change,
I want to send v2 to also remove this mutual exclusion for something 
else board which also used the mutual exclusion.

Thanks
Wei
--
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/