kernel/linux.git/drivers/iommu, branch linux-7.1.y

Merge tag 'dma-mapping-7.1-2026-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux

2026-06-11T21:22:26+00:00

Pull dma-mapping fix from Marek Szyprowski: "Three more fixes for the DMA-mapping code, related to PCI P2PDMA, DMA debug and DMA link ranges API (Li RongQing and Jason Gunthorpe)" * tag 'dma-mapping-7.1-2026-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: iommu/dma: Do not try to iommu_map a 0 length region in swiotlb dma-debug: fix physical address retrieval in debug_dma_sync_sg_for_device dma-mapping: direct: fix missing mapping for THRU_HOST_BRIDGE segments

iommu/dma: Do not try to iommu_map a 0 length region in swiotlb

2026-06-09T20:23:42+00:00

iommu_dma_iova_link_swiotlb() processes a mapping that is unaligned in three parts, the head, middle and trailer. If the middle is empty because there are no aligned pages it will call down to iommu_map() with a 0 size which the iommupt implementation will fail as illegal. It then tries to do an error unwind and starts from the wrong spot corrupting the mapping so the eventual destruction triggers a WARN_ON. Check for 0 length and avoid mapping and use offset not 0 as the starting point to unlink. This is frequently triggered by using some kinds of thunderbolt NVMe drives that trigger forced SWIOTLB for unaligned memory. NVMe seems to pass in oddly aligned buffers for the passthrough commands from smartctl that hit this condition. Cc: stable@vger.kernel.org Fixes: 433a76207dcf ("dma-mapping: Implement link/unlink ranges API") Reported-by: Mark Lord Signed-off-by: Jason Gunthorpe Reviewed-by: Christoph Hellwig Reviewed-by: Leon Romanovsky Reviewed-by: Samiullah Khawaja Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/0-v1-8536728bc89f+469-swiotlb_warn_jgg@nvidia.com

iommu, debugobjects: avoid gcc-16.1 section mismatch warnings

2026-05-28T07:07:12+00:00

gcc-16 has gained some more advanced inter-procedual optimization techniques that enable it to inline the dummy_tlb_add_page() and dummy_tlb_flush() function pointers into a specialized version of __arm_v7s_unmap: WARNING: modpost: vmlinux: section mismatch in reference: __arm_v7s_unmap+0x2cc (section: .text) -> dummy_tlb_add_page (section: .init.text) ERROR: modpost: Section mismatches detected. >From what I can tell, the transformation is correct, as this is only called when __arm_v7s_unmap() is called from arm_v7s_do_selftests(), which is also __init. Since __arm_v7s_unmap() however is not __init, gcc cannot inline the inner function calls directly. In debug_objects_selftest(), the same thing happens. Both the caller and the leaf function are __init, but the IPA pulls it into a non-init one: WARNING: modpost: vmlinux: section mismatch in reference: lookup_object_or_alloc+0x7c (section: .text.lookup_object_or_alloc) -> is_static_object (section: .init.text) Marking the affected functions as not "__init" would reliably avoid this issue but is not a good solution because it removes an otherwise correct annotation. I tried marking the functions as 'noinline', but that ended up not covering all the affected configurations. With some more experimenting, I found that marking these functions as __attribute__((noipa)) is both logical and reliable. In order to keep the syntax readable, add a custom macro for this in include/linux/compiler_attributes.h next to other related macros and use it to annotate both files. Link: https://lore.kernel.org/all/abRB6g-48ZX6Yl2r@willie-the-truck/ Cc: Will Deacon Cc: Thomas Gleixner Cc: Andrew Morton Cc: Miguel Ojeda Cc: linux-kbuild@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Arnd Bergmann Acked-by: Will Deacon Acked-by: Thomas Gleixner Acked-by: Miguel Ojeda Signed-off-by: Joerg Roedel

iommu/vt-d: Simplify calculate_psi_aligned_address()

2026-05-19T08:38:19+00:00

This is doing far too much math for the simple task of finding a power of 2 that fully spans the given range. Use fls directly on the xor which computes the common binary prefix. Signed-off-by: Jason Gunthorpe Reviewed-by: Kevin Tian Link: https://lore.kernel.org/r/0-v2-895748900b39+5303-iommupt_inv_vtd_jgg@nvidia.com Signed-off-by: Lu Baolu Signed-off-by: Joerg Roedel

iommupt: Fix the end_index calculation in __map_range_leaf()

2026-05-15T05:29:16+00:00

Sashiko noticed a mismatch of units in this math: num_leaves is actually the number of leaf *entries* (so a 16-item contiguous leaf is one num_leaves), while index is in items. The mismatch in maths causes __map_range_leaf() to exit early instead of efficiently filling a larger range of contiguous PTEs. The early exit is caught by the functions above and then __map_range_leaf() is re-invoked, so there is no functional issue. Correct the misuse of units by adjusting num_leaves with the leaf size and avoid the performance cost of looping externally. There are also some mismatched types for num_leaves; simplify things to remove the duplicated calculations. Fixes: d6c65b0fd621 ("iommupt: Avoid rewalking during map") Signed-off-by: Jason Gunthorpe Reviewed-by: Samiullah Khawaja Reviewd-by: Pranjal Shrivastava Tested-by: Josua Mayer Signed-off-by: Joerg Roedel

iommupt: Check for missing PAGE_SIZE in the pgsize_bitmap

2026-05-15T05:29:16+00:00

Sashiko pointed out that the driver could drop PAGE_SIZE from the pgsize_bitmap. That is technically allowed but nothing does it, and such an iommu_domain would not be used with the DMA API today. Still, it is against the design and it is trivial to fix up. Lift the PT_WARN_ON to the if branch and just skip the fast path. Fixes: dcd6a011a8d5 ("iommupt: Add map_pages op") Signed-off-by: Jason Gunthorpe Reviewed-by: Pranjal Shrivastava Reviewed-by: Samiullah Khawaja Tested-by: Josua Mayer Signed-off-by: Joerg Roedel

iommu: Handle unmap error when iommu_debug is enabled

2026-05-15T05:29:16+00:00

Sashiko noticed a latent bug where the map error flow called iommu_unmap() which calls iommu_debug_unmap_begin()/iommu_debug_unmap_end() however since this is an error path the map flow never actually established the original iommu_debug_map() it will malfunction. Lift the unmap error handling into iommu_map_nosync() and reorder it so the trace_map()/iommu_debug_map() records the partial mapping and then immediately unmaps it. This avoid creating the unbalanced tracking and provides saner tracing instead of a unmap unmatched to any map. Fixes: ccc21213f013 ("iommu: Add calls for IOMMU_DEBUG_PAGEALLOC") Signed-off-by: Jason Gunthorpe Reviewed-by: Pranjal Shrivastava Reviewed-by: Samiullah Khawaja Reviewed-by: Mostafa Saleh Tested-by: Josua Mayer Signed-off-by: Joerg Roedel

iommu: Fix up map/unmap debugging for iommupt domains

2026-05-15T05:29:15+00:00

Sashiko noticed a few issues in this path, and a few more were found on review. Tidy them up further. These are intertwined because the debug code depends on some of the WARN_ONs to function right: Lift into iommu_map_nosync(): - The might_sleep_if() - 0 pgsize_bitmap WARN_ON - Promote the illegal domain->type to a WARN_ON - WARN_ON for illegal gfp flags Then remove the return 0 since it is now safe to call iommu_debug_map(). Lift into __iommu_unmap(): - 0 pgsize_bitmap WARN_ON - Promote the illegal domain->type to a WARN_ON - iommu_debug_unmap_begin() This now pairs with the unconditional iommu_debug_map() on the mapping side. Thus iommu debugging now works for iommupt along with some of the other debugging features. Fixes: 99fb8afa16ad ("iommupt: Directly call iommupt's unmap_range()") Fixes: d6c65b0fd621 ("iommupt: Avoid rewalking during map") Signed-off-by: Jason Gunthorpe Reviewed-by: Pranjal Shrivastava Reviewed-by: Samiullah Khawaja Reviewed-by: Mostafa Saleh Tested-by: Josua Mayer Signed-off-by: Joerg Roedel

iommu: Fix loss of errno on map failure for classic ops

2026-05-15T05:29:15+00:00

A typo, likely from a rebase, inverted the condition and caused errors to be lost. Fix it to be "if (ret)". This was breaking iommu_create_device_direct_mappings() on drivers that don't use iommupt and don't fully set up their domain in alloc_pages() (i.e., SMMUv2). In this case the first call of iommu_create_device_direct_mappings() should fail due to the incompletely initialized domain. Since it wrongly returns success, the second call to iommu_create_device_direct_mappings() doesn't happen and IOMMU_RESV_DIRECT is never set up. Cc: stable@vger.kernel.org Fixes: d6c65b0fd621 ("iommupt: Avoid rewalking during map") Reported-by: Josua Mayer Closes: https://lore.kernel.org/all/321c2e57-6a17-4aef-ba42-d2ebd577e472@solid-run.com/ Signed-off-by: Jason Gunthorpe Reviewed-by: Pranjal Shrivastava Reviewed-by: Samiullah Khawaja Reviewed-by: Mostafa Saleh Tested-by: Josua Mayer Signed-off-by: Joerg Roedel

iommu/vt-d: Avoid NULL pointer dereference or refcount corruption

2026-05-11T08:19:37+00:00

Commit 60f030f7418d ("iommu/vt-d: Avoid use of NULL after WARN_ON_ONCE") fixed a NULL pointer dereference in an unlikely situation partly. If dev_pasid is not found in the dev_pasids list, it remains NULL. However, the teardown operations are executed unconditionally, this lead to a NULL pointer dereference or refcount corruption. If the domain was never attached to this IOMMU, info will be NULL, which would cause an immediate dereference when checking --info->refcnt. Even if info is not NULL, decrementing the refcount without having removed a valid PASID might unbalance the count. This could lead to premature dropping of the refcount to 0, potentially causing a use-after-free for the remaining active devices sharing the domain. Fix it by returning early if dev_pasid is NULL, before executing the teardown operations. Issue found by AI review and suggested by Kevin Tian. https://sashiko.dev/#/patchset/20260421031347.1408890-1-zhenzhong.duan%40intel.com Fixes: 60f030f7418d ("iommu/vt-d: Avoid use of NULL after WARN_ON_ONCE") Cc: stable@vger.kernel.org Suggested-by: Kevin Tian Signed-off-by: Zhenzhong Duan Reviewed-by: Kevin Tian Link: https://lore.kernel.org/r/20260422033538.95000-1-zhenzhong.duan@intel.com Signed-off-by: Lu Baolu Signed-off-by: Joerg Roedel