From e82752d8b5a7e0a5e4d607fd8713549e2a4e2741 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Fri, 28 May 2010 14:26:48 +0200 Subject: [PATCH] x86/amd-iommu: Fix crash when request_mem_region fails When request_mem_region fails the error path tries to disable the IOMMUs. This accesses the mmio-region which was not allocated leading to a kernel crash. This patch fixes the issue. Cc: stable@kernel.org Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu_init.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c index 3bacb4d..1405346 100644 --- a/arch/x86/kernel/amd_iommu_init.c +++ b/arch/x86/kernel/amd_iommu_init.c @@ -287,8 +287,12 @@ static u8 * __init iommu_map_mmio_space(u64 address) { u8 *ret; - if (!request_mem_region(address, MMIO_REGION_LENGTH, "amd_iommu")) + if (!request_mem_region(address, MMIO_REGION_LENGTH, "amd_iommu")) { + pr_err("AMD-Vi: Can not reserve memory region %llx for mmio\n", + address); + pr_err("AMD-Vi: This is a BIOS bug. Please contact your hardware vendor\n"); return NULL; + } ret = ioremap_nocache(address, MMIO_REGION_LENGTH); if (ret != NULL) @@ -1314,7 +1318,7 @@ static int __init amd_iommu_init(void) ret = amd_iommu_init_dma_ops(); if (ret) - goto free; + goto free_disable; amd_iommu_init_api(); @@ -1332,9 +1336,10 @@ static int __init amd_iommu_init(void) out: return ret; -free: +free_disable: disable_iommus(); +free: amd_iommu_uninit_devices(); free_pages((unsigned long)amd_iommu_pd_alloc_bitmap, -- 2.7.4