From 0f764806438d5576ac58898332e5dcf30bb8a679 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Mon, 21 Dec 2009 15:51:23 +0100 Subject: [PATCH] x86/amd-iommu: Fix initialization failure panic The assumption that acpi_table_parse passes the return value of the hanlder function to the caller proved wrong recently. The return value of the handler function is totally ignored. This makes the initialization code for AMD IOMMU buggy in a way that could cause a kernel panic on initialization. This patch fixes the issue in the AMD IOMMU driver. Cc: stable@kernel.org Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu_init.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c index 1dca9c34eaeb..fb490ce7dd55 100644 --- a/arch/x86/kernel/amd_iommu_init.c +++ b/arch/x86/kernel/amd_iommu_init.c @@ -137,6 +137,11 @@ int amd_iommus_present; /* IOMMUs have a non-present cache? */ bool amd_iommu_np_cache __read_mostly; +/* + * Set to true if ACPI table parsing and hardware intialization went properly + */ +static bool amd_iommu_initialized; + /* * List of protection domains - used during resume */ @@ -929,6 +934,8 @@ static int __init init_iommu_all(struct acpi_table_header *table) } WARN_ON(p != end); + amd_iommu_initialized = true; + return 0; } @@ -1263,6 +1270,9 @@ static int __init amd_iommu_init(void) if (acpi_table_parse("IVRS", init_iommu_all) != 0) goto free; + if (!amd_iommu_initialized) + goto free; + if (acpi_table_parse("IVRS", init_memory_definitions) != 0) goto free; -- 2.20.1