Re: [patch 01/22] AMD IOMMU: enable device isolation per default

Pavel Machek
2008-12-19T07:21:55Z

On Tue 2008-12-16 16:03:53, Greg KH wrote:
> 2.6.27-stable review patch. If anyone has any objections, please let us know.
>
> ------------------
>
> From: Joerg Roedel <joerg.roedel@amd.com>
>
> commit 3ce1f93c6d53c3f91c3846cf66b018276c8ac2e7 upstream.
>
> Impact: makes device isolation the default for AMD IOMMU
>
> Some device drivers showed double-free bugs of DMA memory while testing
> them with AMD IOMMU. If all devices share the same protection domain
> this can lead to data corruption and data loss. Prevent this by putting
> each device into its own protection domain per default.
>
> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

This does not look like 'fix for a serious bug' to
me. stable_kernel_rules.txt says '...not a "this could be a problem"
type thing'.

Yes, maybe iommu is mature enough that we want it enabled, but...

(Or maybe Documentation/stable_kernel_rules.txt needs updating. The
patch for penguin dirty feet already got in.....)
Pavel
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