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Subject: Re: [PATCH 3/4] BUG_ON on kernel misbehavior on A100U2W driver
From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: Mikulas Patocka <mpatocka@redhat.com>
Cc: torvalds@linux-foundation.org, linux-scsi@vger.kernel.org,
       linux-kernel@vger.kernel.org
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Date: Tue, 15 Jul 2008 10:17:47 -0500
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On Tue, 2008-07-15 at 10:14 -0400, Mikulas Patocka wrote:
> With broken Sparc64 IOMMU accounting, the kernel submits larger requests 
> then allowed. Better to crash on BUG than corrupt memory. This needs to be 
> fixed in sparc64 code.

This analysis is correct ... and the reason we don't add driver work
arounds, so it really needs to be fixed in sparc, not worked around in
the driver.

James