Re: [PATCH v2] iommu/amd: Fix get_acpihid_device_id()

From: Joerg Roedel
Date: Wed May 13 2020 - 05:15:42 EST


On Mon, May 11, 2020 at 10:33:36AM -0600, Raul E Rangel wrote:
> acpi_dev_hid_uid_match() expects a null pointer for UID if it doesn't
> exist. The acpihid_map_entry contains a char buffer for holding the
> UID. If no UID was provided in the IVRS table, this buffer will be
> zeroed. If we pass in a null string, acpi_dev_hid_uid_match() will
> return false because it will try and match an empty string to the ACPI
> UID of the device.
>
> Fixes: ae5e6c6439c3 ("iommu/amd: Switch to use acpi_dev_hid_uid_match()")
> Suggested-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Signed-off-by: Raul E Rangel <rrangel@xxxxxxxxxxxx>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> ---
>
> Changes in v2:
> - Added Suggested by
> - Fixed commit description
> - Decided to keep `p->uid[0]` instead of `*p->uid` since the data member is an array instead of a pointer.
> - Used clang-format
>
> drivers/iommu/amd_iommu.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)

Applied for v5.7, thanks Raul.