kernel/linux.git/drivers/iommu/amd/init.c, branch v6.12.81

Revert "iommu/amd: Skip enabling command/event buffers for kdump"

2026-01-11T14:25:21+00:00

This reverts commit 3344716ddee01d7caa35b470d30fd87781c661b1 which is commit 9be15fbfc6c5c89c22cf6e209f66ea43ee0e58bb upstream. This causes problems in older kernel trees as SNP host kdump is not supported in them, so drop it from the stable branches. Reported-by: Ashish Kalra Link: https://lore.kernel.org/r/dacdff7f-0606-4ed5-b056-2de564404d51@amd.com Cc: Vasant Hegde Cc: Sairaj Kodilkar Cc: Joerg Roedel Cc: Sasha Levin Signed-off-by: Greg Kroah-Hartman

iommu/amd: Fix pci_segment memleak in alloc_pci_segment()

2026-01-08T09:14:39+00:00

commit 75ba146c2674ba49ed8a222c67f9abfb4a4f2a4f upstream. Fix a memory leak of struct amd_iommu_pci_segment in alloc_pci_segment() when system memory (or contiguous memory) is insufficient. Fixes: 04230c119930 ("iommu/amd: Introduce per PCI segment device table") Fixes: eda797a27795 ("iommu/amd: Introduce per PCI segment rlookup table") Fixes: 99fc4ac3d297 ("iommu/amd: Introduce per PCI segment alias_table") Cc: stable@vger.kernel.org Signed-off-by: Jinhui Guo Signed-off-by: Joerg Roedel Signed-off-by: Greg Kroah-Hartman

iommu/amd: Skip enabling command/event buffers for kdump

2025-11-13T20:34:19+00:00

[ Upstream commit 9be15fbfc6c5c89c22cf6e209f66ea43ee0e58bb ] After a panic if SNP is enabled in the previous kernel then the kdump kernel boots with IOMMU SNP enforcement still enabled. IOMMU command buffers and event buffer registers remain locked and exclusive to the previous kernel. Attempts to enable command and event buffers in the kdump kernel will fail, as hardware ignores writes to the locked MMIO registers as per AMD IOMMU spec Section 2.12.2.1. Skip enabling command buffers and event buffers for kdump boot as they are already enabled in the previous kernel. Reviewed-by: Vasant Hegde Tested-by: Sairaj Kodilkar Signed-off-by: Ashish Kalra Link: https://lore.kernel.org/r/576445eb4f168b467b0fc789079b650ca7c5b037.1756157913.git.ashish.kalra@amd.com Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin

iommu/amd: Avoid stack buffer overflow from kernel cmdline

2025-08-28T14:31:13+00:00

[ Upstream commit 8503d0fcb1086a7cfe26df67ca4bd9bd9e99bdec ] While the kernel command line is considered trusted in most environments, avoid writing 1 byte past the end of "acpiid" if the "str" argument is maximum length. Reported-by: Simcha Kosman Closes: https://lore.kernel.org/all/AS8P193MB2271C4B24BCEDA31830F37AE84A52@AS8P193MB2271.EURP193.PROD.OUTLOOK.COM Fixes: b6b26d86c61c ("iommu/amd: Add a length limitation for the ivrs_acpihid command-line parameter") Signed-off-by: Kees Cook Reviewed-by: Ankit Soni Link: https://lore.kernel.org/r/20250804154023.work.970-kees@kernel.org Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin

iommu/amd: Fix potential buffer overflow in parse_ivrs_acpihid

2025-05-09T07:50:33+00:00

commit 8dee308e4c01dea48fc104d37f92d5b58c50b96c upstream. There is a string parsing logic error which can lead to an overflow of hid or uid buffers. Comparing ACPIID_LEN against a total string length doesn't take into account the lengths of individual hid and uid buffers so the check is insufficient in some cases. For example if the length of hid string is 4 and the length of the uid string is 260, the length of str will be equal to ACPIID_LEN + 1 but uid string will overflow uid buffer which size is 256. The same applies to the hid string with length 13 and uid string with length 250. Check the length of hid and uid strings separately to prevent buffer overflow. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: ca3bf5d47cec ("iommu/amd: Introduces ivrs_acpihid kernel parameter") Cc: stable@vger.kernel.org Signed-off-by: Pavel Paklov Link: https://lore.kernel.org/r/20250325092259.392844-1-Pavel.Paklov@cyberprotect.ru Signed-off-by: Joerg Roedel Signed-off-by: Greg Kroah-Hartman

iommu/amd: Expicitly enable CNTRL.EPHEn bit in resume path

2025-02-21T13:01:22+00:00

[ Upstream commit ef75966abf950c0539534effa4960caa29fb7167 ] With recent kernel, AMDGPU failed to resume after suspend on certain laptop. Sample log: ----------- Nov 14 11:52:19 Thinkbook kernel: iommu ivhd0: AMD-Vi: Event logged [ILLEGAL_DEV_TABLE_ENTRY device=0000:06:00.0 pasid=0x00000 address=0x135300000 flags=0x0080] Nov 14 11:52:19 Thinkbook kernel: AMD-Vi: DTE[0]: 7d90000000000003 Nov 14 11:52:19 Thinkbook kernel: AMD-Vi: DTE[1]: 0000100103fc0009 Nov 14 11:52:19 Thinkbook kernel: AMD-Vi: DTE[2]: 2000000117840013 Nov 14 11:52:19 Thinkbook kernel: AMD-Vi: DTE[3]: 0000000000000000 This is because in resume path, CNTRL[EPHEn] is not set. Fix this by setting CNTRL[EPHEn] to 1 in resume path if EFR[EPHSUP] is set. Note May be better approach is to save the control register in suspend path and restore it in resume path instead of trying to set indivisual bits. We will have separate patch for that. Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219499 Fixes: c4cb23111103 ("iommu/amd: Add support for enable/disable IOPF") Tested-by: Hamish McIntyre-Bhatty Signed-off-by: Vasant Hegde Link: https://lore.kernel.org/r/20250127094411.5931-1-vasant.hegde@amd.com Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin

iommu/amd: Add kernel parameters to limit V1 page-sizes

2024-09-10T09:48:57+00:00

Add two new kernel command line parameters to limit the page-sizes used for v1 page-tables: nohugepages - Limits page-sizes to 4KiB v2_pgsizes_only - Limits page-sizes to 4Kib/2Mib/1GiB; The same as the sizes used with v2 page-tables This is needed for multiple scenarios. When assigning devices to SEV-SNP guests the IOMMU page-sizes need to match the sizes in the RMP table, otherwise the device will not be able to access all shared memory. Also, some ATS devices do not work properly with arbitrary IO page-sizes as supported by AMD-Vi, so limiting the sizes used by the driver is a suitable workaround. All-in-all, these parameters are only workarounds until the IOMMU core and related APIs gather the ability to negotiate the page-sizes in a better way. Signed-off-by: Joerg Roedel Reviewed-by: Vasant Hegde Link: https://lore.kernel.org/r/20240905072240.253313-1-joro@8bytes.org

iommu/amd: Update PASID, GATS, GLX, SNPAVICSUP feature related macros

2024-08-23T09:17:47+00:00

Clean up and reorder them according to the bit index. There is no functional change. Suggested-by: Jason Gunthorpe Signed-off-by: Suravee Suthikulpanit Reviewed-by: Vasant Hegde Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/20240816221650.62295-1-suravee.suthikulpanit@amd.com Signed-off-by: Joerg Roedel

iommu/amd: Fix GT feature enablement again

2024-06-27T10:14:19+00:00

Current code configures GCR3 even when device is attached to identity domain. So that we can support SVA with identity domain. This means in attach device path it updates Guest Translation related bits in DTE. Commit de111f6b4f6a ("iommu/amd: Enable Guest Translation after reading IOMMU feature register") missed to enable Control[GT] bit in resume path. Its causing certain laptop to fail to resume after suspend. This is because we have inconsistency between between control register (GT is disabled) and DTE (where we have enabled guest translation related bits) in resume path. And IOMMU hardware throws ILLEGAL_DEV_TABLE_ENTRY. Fix it by enabling GT bit in resume path. Reported-by: Błażej Szczygieł Link: https://bugzilla.kernel.org/show_bug.cgi?id=218975 Fixes: de111f6b4f6a ("iommu/amd: Enable Guest Translation after reading IOMMU feature register") Tested-by: Błażej Szczygieł Signed-off-by: Vasant Hegde Reviewed-by: Jerry Snitselaar Link: https://lore.kernel.org/r/20240621101533.20216-1-vasant.hegde@amd.com Signed-off-by: Joerg Roedel

iommu/amd: Fix panic accessing amd_iommu_enable_faulting

2024-06-13T09:16:05+00:00

This fixes a bug introduced by commit d74169ceb0d2 ("iommu/vt-d: Allocate DMAR fault interrupts locally"). The panic happens when amd_iommu_enable_faulting is called from CPUHP_AP_ONLINE_DYN context. Fixes: d74169ceb0d2 ("iommu/vt-d: Allocate DMAR fault interrupts locally") Signed-off-by: Dimitri Sivanich Tested-by: Yi Zhang Reviewed-by: Jerry Snitselaar Reviewed-by: Vasant Hegde Link: https://lore.kernel.org/r/ZljHE/R4KLzGU6vx@hpe.com Signed-off-by: Joerg Roedel