From 84c43d06a8bf9c33ea03201acbcd5d99b7ec6488 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Tue, 27 Sep 2022 21:10:33 +0800 Subject: [PATCH] iommu/amd: Increase timeout waiting for GA log enablement MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit stable inclusion from stable-v5.10.121 commit de6f6b5400be79457eb7a17fe1a0f499299f16b8 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6CQ Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=de6f6b5400be79457eb7a17fe1a0f499299f16b8 -------------------------------- [ 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" Cc: Jörg-Volker Peetz Fixes: 8bda0cfbdc1a ("iommu/amd: Detect and initialize guest vAPIC log") Signed-off-by: Joerg Roedel Link: https://lore.kernel.org/r/20220520102214.12563-1-joro@8bytes.org Signed-off-by: Sasha Levin Signed-off-by: Zheng Zengkai Acked-by: Xie XiuQi --- drivers/iommu/amd/init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index 6eaefc9e7b3d..e988f6f198c5 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -84,7 +84,7 @@ #define ACPI_DEVFLAG_LINT1 0x80 #define ACPI_DEVFLAG_ATSDIS 0x10000000 -#define LOOP_TIMEOUT 100000 +#define LOOP_TIMEOUT 2000000 /* * ACPI table definitions * -- GitLab