From ee2fa7435b6dddf1ca119f298ad0100cf50c0397 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 17 Sep 2008 13:47:25 +0200 Subject: AMD IOMMU: set iommu sunc flag after command queuing The iommu->need_sync flag must be set after the command is queued to avoid race conditions. Signed-off-by: Joerg Roedel Signed-off-by: Ingo Molnar --- arch/x86/kernel/amd_iommu.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'arch/x86/kernel/amd_iommu.c') diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 69b4d060b21c..a96d8c049a88 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -140,6 +140,7 @@ static int iommu_completion_wait(struct amd_iommu *iommu) static int iommu_queue_inv_dev_entry(struct amd_iommu *iommu, u16 devid) { struct iommu_cmd cmd; + int ret; BUG_ON(iommu == NULL); @@ -147,9 +148,11 @@ static int iommu_queue_inv_dev_entry(struct amd_iommu *iommu, u16 devid) CMD_SET_TYPE(&cmd, CMD_INV_DEV_ENTRY); cmd.data[0] = devid; + ret = iommu_queue_command(iommu, &cmd); + iommu->need_sync = 1; - return iommu_queue_command(iommu, &cmd); + return ret; } /* @@ -159,6 +162,7 @@ static int iommu_queue_inv_iommu_pages(struct amd_iommu *iommu, u64 address, u16 domid, int pde, int s) { struct iommu_cmd cmd; + int ret; memset(&cmd, 0, sizeof(cmd)); address &= PAGE_MASK; @@ -171,9 +175,11 @@ static int iommu_queue_inv_iommu_pages(struct amd_iommu *iommu, if (pde) /* PDE bit - we wan't flush everything not only the PTEs */ cmd.data[2] |= CMD_INV_IOMMU_PAGES_PDE_MASK; + ret = iommu_queue_command(iommu, &cmd); + iommu->need_sync = 1; - return iommu_queue_command(iommu, &cmd); + return ret; } /* -- cgit v1.2.3 From 7e4f88da7bf1887563f70bd5edbbd0479e31dc12 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 17 Sep 2008 14:19:15 +0200 Subject: AMD IOMMU: protect completion wait loop with iommu lock The unlocked polling of the ComWaitInt bit in the IOMMU completion wait path is racy. Protect it with the iommu lock. Signed-off-by: Joerg Roedel Signed-off-by: Ingo Molnar --- arch/x86/kernel/amd_iommu.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'arch/x86/kernel/amd_iommu.c') diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index a96d8c049a88..042fdc27bc92 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -101,10 +101,10 @@ static int iommu_queue_command(struct amd_iommu *iommu, struct iommu_cmd *cmd) */ static int iommu_completion_wait(struct amd_iommu *iommu) { - int ret, ready = 0; + int ret = 0, ready = 0; unsigned status = 0; struct iommu_cmd cmd; - unsigned long i = 0; + unsigned long flags, i = 0; memset(&cmd, 0, sizeof(cmd)); cmd.data[0] = CMD_COMPL_WAIT_INT_MASK; @@ -112,10 +112,12 @@ static int iommu_completion_wait(struct amd_iommu *iommu) iommu->need_sync = 0; - ret = iommu_queue_command(iommu, &cmd); + spin_lock_irqsave(&iommu->lock, flags); + + ret = __iommu_queue_command(iommu, &cmd); if (ret) - return ret; + goto out; while (!ready && (i < EXIT_LOOP_COUNT)) { ++i; @@ -130,6 +132,8 @@ static int iommu_completion_wait(struct amd_iommu *iommu) if (unlikely((i == EXIT_LOOP_COUNT) && printk_ratelimit())) printk(KERN_WARNING "AMD IOMMU: Completion wait loop failed\n"); +out: + spin_unlock_irqrestore(&iommu->lock, flags); return 0; } -- cgit v1.2.3