From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King Subject: Re: [PATCHSET] block: fix PIO cache coherency bug, take 2 Date: Sun, 4 Jun 2006 21:44:44 +0100 Message-ID: <20060604204444.GF4484@flint.arm.linux.org.uk> References: <1149392479501-git-send-email-htejun@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1149392479501-git-send-email-htejun@gmail.com> Sender: linux-scsi-owner@vger.kernel.org To: Tejun Heo Cc: Jens Axboe , James Bottomley , Dave Miller , bzolnier@gmail.com, james.steward@dynamicratings.com, jgarzik@pobox.com, mattjreimer@gmail.com, Guennadi Liakhovetski , lkml , linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org List-Id: linux-ide@vger.kernel.org On Sun, Jun 04, 2006 at 12:41:19PM +0900, Tejun Heo wrote: > Russell, can you please verify arm's flush_kernel_dcache_page()? That should be fine from a theoretical standpoint, but I can't say much more than that - I have _great_ difficulty in reproducing the problem with IDE and as such I consider myself out of the game of testing for this problem: | Date: Fri, 13 Jan 2006 22:02:15 +0000 | From: Russell King | To: Tejun Heo | Subject: Re: [PATCHSET] block: fix PIO cache coherency bug | | On Sat, Jan 14, 2006 at 12:24:16AM +0900, Tejun Heo wrote: | > Russell, can you please test whether this fixes the bug on arm? If | > this fixes the bug and people agree with the approach, I'll follow up | > with patches for yet unconverted drivers and documentation update. | | Unfortunately, as I previously explained, I'm not able to test this. | The reason is that in order to reproduce the bug, you need a system | with a VIVT write-back write-allocate cache. | | Unfortunately, the few systems I have which have such a cache do not | have IDE, SCSI nor SATA (not even PCMCIA.) I suggest contacting the | folk who reported the bug in the first instance. You need to approach other members of the ARM community to test these patches. Unfortunately I don't have a list of who has found the problem and who is in a state to be able to reproduce it - since most members are embedded engineers, they tend to move on to other projects quite rapidly. What I suggest is that we just throw _something_ which looks right into the kernel and see what happens. I can't see any other possible way to proceed, _especially_ as we've had 6 months of very little progress on this issue. > I tried to implement flush_anon_page() too but didn't know what to do > with anon_vma object. I'm not sure what this is about... -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 Serial core