From 6082ee72e9d89e80a664418be06f47d728243e85 Mon Sep 17 00:00:00 2001 From: Nicolas Iooss Date: Sun, 26 Jun 2016 10:33:29 +0200 Subject: iommu/amd: Initialize devid variable before using it Commit 2a0cb4e2d423 ("iommu/amd: Add new map for storing IVHD dev entry type HID") added a call to DUMP_printk in init_iommu_from_acpi() which used the value of devid before this variable was initialized. Fixes: 2a0cb4e2d423 ('iommu/amd: Add new map for storing IVHD dev entry type HID') Signed-off-by: Nicolas Iooss Signed-off-by: Joerg Roedel --- drivers/iommu/amd_iommu_init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/iommu/amd_iommu_init.c') diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c index 9e0034196e10..d091defc3426 100644 --- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -1107,13 +1107,13 @@ static int __init init_iommu_from_acpi(struct amd_iommu *iommu, break; } + devid = e->devid; DUMP_printk(" DEV_ACPI_HID(%s[%s])\t\tdevid: %02x:%02x.%x\n", hid, uid, PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid)); - devid = e->devid; flags = e->flags; ret = add_acpi_hid_device(hid, uid, &devid, false); -- cgit v1.2.3-70-g09d2 From 522e5cb76d0663c88f96b6a8301451c8efa37207 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Fri, 1 Jul 2016 16:42:55 +0200 Subject: iommu/amd: Fix unity mapping initialization race There is a race condition in the AMD IOMMU init code that causes requested unity mappings to be blocked by the IOMMU for a short period of time. This results on boot failures and IO_PAGE_FAULTs on some machines. Fix this by making sure the unity mappings are installed before all other DMA is blocked. Fixes: aafd8ba0ca74 ('iommu/amd: Implement add_device and remove_device') Cc: stable@vger.kernel.org # v4.2+ Signed-off-by: Joerg Roedel --- drivers/iommu/amd_iommu_init.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'drivers/iommu/amd_iommu_init.c') diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c index d091defc3426..59741ead7e15 100644 --- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -1568,13 +1568,23 @@ static int __init amd_iommu_init_pci(void) break; } + /* + * Order is important here to make sure any unity map requirements are + * fulfilled. The unity mappings are created and written to the device + * table during the amd_iommu_init_api() call. + * + * After that we call init_device_table_dma() to make sure any + * uninitialized DTE will block DMA, and in the end we flush the caches + * of all IOMMUs to make sure the changes to the device table are + * active. + */ + ret = amd_iommu_init_api(); + init_device_table_dma(); for_each_iommu(iommu) iommu_flush_all_caches(iommu); - ret = amd_iommu_init_api(); - if (!ret) print_iommu_info(); -- cgit v1.2.3-70-g09d2