From b26e81b871bd18184968f0bb3f12945906eadfce Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 3 Sep 2009 15:08:09 +0200 Subject: x86/amd-iommu: Panic if IOMMU command buffer reset fails To prevent the driver from doing recursive command buffer resets, just panic when that recursion happens. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/amd_iommu_types.h | 3 +++ arch/x86/kernel/amd_iommu.c | 7 +++++++ 2 files changed, 10 insertions(+) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h index c54bc979dc1..e676746a4a3 100644 --- a/arch/x86/include/asm/amd_iommu_types.h +++ b/arch/x86/include/asm/amd_iommu_types.h @@ -337,6 +337,9 @@ struct amd_iommu { /* if one, we need to send a completion wait command */ bool need_sync; + /* becomes true if a command buffer reset is running */ + bool reset_in_progress; + /* default dma_ops domain for that IOMMU */ struct dma_ops_domain *default_dom; }; diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 2333d615f5e..b62a2f64dfc 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -553,9 +553,16 @@ static void reset_iommu_command_buffer(struct amd_iommu *iommu) { pr_err("AMD-Vi: Resetting IOMMU command buffer\n"); + if (iommu->reset_in_progress) + panic("AMD-Vi: ILLEGAL_COMMAND_ERROR while resetting command buffer\n"); + + iommu->reset_in_progress = true; + amd_iommu_reset_cmd_buffer(iommu); flush_all_devices_for_iommu(iommu); flush_all_domains_on_iommu(iommu); + + iommu->reset_in_progress = false; } /**************************************************************************** -- cgit v1.2.3