From: Kim Phillips <kim.phillips@amd.com>
Date: Mon, 19 Sep 2022 10:56:37 -0500
Subject: iommu/amd: Fix ivrs_acpihid cmdline parsing code
Git-commit: 5f18e9f8868c6d4eae71678e7ebd4977b7d8c8cf
Patch-mainline: v6.2-rc1
References: git-fixes
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>
---
drivers/iommu/amd/init.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 1a2d425bf568..d14da30b8706 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -3488,6 +3488,13 @@ static int __init parse_ivrs_acpihid(char *str)
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));