[PATCH resend] powernv/iommu: disable IOMMU bypass with param iommu=nobypass

Michael Ellerman mpe at ellerman.id.au
Thu Jan 22 12:05:31 AEDT 2015


On Wed, 2015-01-21 at 13:23 -0200, Thadeu Lima de Souza Cascardo wrote:
> When IOMMU bypass is enabled, a PCI device can read and write memory
> that was not mapped by the driver without causing an EEH. That might
> cause memory corruption, for example.
> 
> When we disable bypass, DMA reads and writes to addresses not mapped by
> the IOMMU will cause an EEH, allowing us to debug such issues.
> 
> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo at linux.vnet.ibm.com>
> Reviewed-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
> ---
>  Documentation/kernel-parameters.txt       |    2 ++
>  arch/powerpc/platforms/powernv/pci-ioda.c |   24 +++++++++++++++++++++++-
>  2 files changed, 25 insertions(+), 1 deletion(-)

Is this unchanged since v2?

It's marked as under review in patchwork which means I'm looking at it:

  http://patchwork.ozlabs.org/patch/402682/


Please check patchwork in future.

cheers




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