From: Kim Phillips kim.phillips@amd.com
commit 5f18e9f8868c6d4eae71678e7ebd4977b7d8c8cf upstream.
The second (UID) strcmp in acpi_dev_hid_uid_match considers "0" and "00" different, which can prevent device registration.
Have the AMD IOMMU driver's ivrs_acpihid parsing code remove any leading zeroes to make the UID strcmp succeed. Now users can safely specify "AMDxxxxx:00" or "AMDxxxxx:0" and expect the same behaviour.
Fixes: ca3bf5d47cec ("iommu/amd: Introduces ivrs_acpihid kernel parameter") Signed-off-by: Kim Phillips kim.phillips@amd.com Cc: stable@vger.kernel.org Cc: Suravee Suthikulpanit Suravee.Suthikulpanit@amd.com Cc: Joerg Roedel jroedel@suse.de Link: https://lore.kernel.org/r/20220919155638.391481-1-kim.phillips@amd.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iommu/amd_iommu_init.c | 7 +++++++ 1 file changed, 7 insertions(+)
--- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -2946,6 +2946,13 @@ static int __init parse_ivrs_acpihid(cha return 1; }
+ /* + * Ignore leading zeroes after ':', so e.g., AMDI0095:00 + * will match AMDI0095:0 in the second strcmp in acpi_dev_hid_uid_match + */ + while (*uid == '0' && *(uid + 1)) + uid++; + i = early_acpihid_map_size++; memcpy(early_acpihid_map[i].hid, hid, strlen(hid)); memcpy(early_acpihid_map[i].uid, uid, strlen(uid));