From: Joerg Roedel jroedel@suse.de
[ Upstream commit 42bb5aa043382f09bef2cc33b8431be867c70f8e ]
On some systems it can take a long time for the hardware to enable the GA log of the AMD IOMMU. The current wait time is only 0.1ms, but testing showed that it can take up to 14ms for the GA log to enter running state after it has been enabled.
Sometimes the long delay happens when booting the system, sometimes only on resume. Adjust the timeout accordingly to not print a warning when hardware takes a longer than usual.
There has already been an attempt to fix this with commit
9b45a7738eec ("iommu/amd: Fix loop timeout issue in iommu_ga_log_enable()")
But that commit was based on some wrong math and did not fix the issue in all cases.
Cc: "D. Ziegfeld" dzigg@posteo.de Cc: Jörg-Volker Peetz jvpeetz@web.de Fixes: 8bda0cfbdc1a ("iommu/amd: Detect and initialize guest vAPIC log") Signed-off-by: Joerg Roedel jroedel@suse.de Link: https://lore.kernel.org/r/20220520102214.12563-1-joro@8bytes.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/amd_iommu_init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -86,7 +86,7 @@ #define ACPI_DEVFLAG_LINT1 0x80 #define ACPI_DEVFLAG_ATSDIS 0x10000000
-#define LOOP_TIMEOUT 100000 +#define LOOP_TIMEOUT 2000000 /* * ACPI table definitions *