kernel/linux.git/drivers/virtio, branch v6.18.40

virtio: rtc: tear down old virtqueues before restore

2026-07-24T14:16:07+00:00

[ Upstream commit 548d2208455f14e6121404c6e30e997bfe0cd264 ] virtio_device_restore() resets the device and restores the negotiated features before calling ->restore(). viortc_freeze() intentionally leaves the existing virtqueues in place so the alarm queue can still wake the system, but viortc_restore() immediately calls viortc_init_vqs() without first deleting those old queues. If virtqueue reinitialization fails on virtio-pci, the transport error path can run vp_del_vqs() against a newly allocated vp_dev->vqs array while vdev->vqs still contains the old virtqueues. vp_del_vqs() then looks up queue state through the new array and can dereference a NULL info pointer in vp_del_vq(), crashing the guest kernel during restore. This can also happen during a non-faulty reinitialization, when one of the vp_find_vqs_msix() attempts is unsuccessful before a later attempt would succeed. Delete the stale virtqueues before rebuilding them. If restore fails before virtio_device_ready(), reuse the remove path to stop the device. Once the device is ready, return errors directly instead of deleting the virtqueues again. Fixes: 0623c7592768 ("virtio_rtc: Add module and driver core") Signed-off-by: Jia Jia Reviewed-by: Peter Hilber Signed-off-by: Michael S. Tsirkin Message-ID: <20260507120801.3677552-1-physicalmtea@gmail.com> Signed-off-by: Sasha Levin

virtio-mmio: fix device release warning on module unload

2026-07-18T14:53:13+00:00

commit c687bc35694698ec4c7f92bf929c3d659f0cecb8 upstream. Driver core expects devices to be allocated dynamically and complains loudly when a device that lacks a release function is freed. Use __root_device_register() to allocate and register the root device instead of open coding using a static device. Note that root_device_register(), which also creates a link to the module, cannot be used as the device is registered when parsing the module parameters which happens before the module kobject has been set up. Fixes: 81a054ce0b46 ("virtio-mmio: Devices parameter parsing") Cc: stable@vger.kernel.org # 3.5 Cc: Pawel Moll Signed-off-by: Johan Hovold Signed-off-by: Michael S. Tsirkin Message-ID: <20260427143710.14702-1-johan@kernel.org> Signed-off-by: Greg Kroah-Hartman

virtio_pci: fix vq info pointer lookup via wrong index

2026-07-18T14:53:13+00:00

commit f7d380fb525c13bdd114369a1979c80c346e6abc upstream. Unbinding a virtio balloon device: echo virtio0 > /sys/bus/virtio/drivers/virtio_balloon/unbind triggers a NULL pointer dereference. The dmesg says: BUG: kernel NULL pointer dereference, address: 0000000000000008 [...] RIP: 0010:__list_del_entry_valid_or_report+0x5/0xf0 Call Trace: vp_del_vqs+0x121/0x230 remove_common+0x135/0x150 virtballoon_remove+0xee/0x100 virtio_dev_remove+0x3b/0x80 device_release_driver_internal+0x187/0x2c0 unbind_store+0xb9/0xe0 kernfs_fop_write_iter.llvm.11660790530567441834+0xf6/0x180 vfs_write+0x2a9/0x3b0 ksys_write+0x5c/0xd0 do_syscall_64+0x54/0x230 entry_SYSCALL_64_after_hwframe+0x29/0x31 [...] The virtio_balloon device registers 5 queues (inflate, deflate, stats, free_page, reporting) but only the first two are unconditional. The stats, free_page and reporting queues are each conditional on their respective feature bits. When any of these features are absent, the corresponding vqs_info entry has name == NULL, creating holes in the array. The root cause is an indexing mismatch introduced when vq info storage was changed to be passed as an argument. vp_find_vqs_msix() and vp_find_vqs_intx() store the info pointer at vp_dev->vqs[i], where 'i' is the caller's sparse array index. However, the virtqueue itself gets vq->index assigned from queue_idx, a dense index that skips NULL entries. When holes exist, 'i' and queue_idx diverge. Later, vp_del_vqs() looks up info via vp_dev->vqs[vq->index] using the dense index into the sparsely-populated array, and hits NULL. Fix this by storing info at vp_dev->vqs[queue_idx] instead of vp_dev->vqs[i], so the store index matches the lookup index (vq->index). Apply the fix to both the MSIX and INTX paths. Cc: Yichun Zhang Cc: Jiri Pirko Cc: stable@vger.kernel.org # v6.11+ Tested-by: Yuka Fixes: 89a1c435aec2 ("virtio_pci: pass vq info as an argument to vp_setup_vq()") Signed-off-by: Ammar Faizi Message-Id: <20260315141808.547081-1-ammarfaizi2@openresty.com> Signed-off-by: Michael S. Tsirkin Signed-off-by: Greg Kroah-Hartman

virtio: clean up features qword/dword terms

2025-12-18T13:03:24+00:00

[ Upstream commit 9513f25056b22100ddffe24898c587873b0d022c ] virtio pci uses word to mean "16 bits". mmio uses it to mean "32 bits". To avoid confusion, let's avoid the term in core virtio altogether. Just say U64 to mean "64 bit". Fixes: e7d4c1c5a546 ("virtio: introduce extended features") Cc: Paolo Abeni Acked-by: Jason Wang Message-ID: Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin

virtio: fix kernel-doc for mapping/free_coherent functions

2025-12-18T13:03:23+00:00

[ Upstream commit f8113000855a8cc2c6d8e19b97a390f1c082285d ] Documentation build reported: WARNING: ./drivers/virtio/virtio_ring.c:3174 function parameter 'vaddr' not described in 'virtqueue_map_free_coherent' WARNING: ./drivers/virtio/virtio_ring.c:3308 expecting prototype for virtqueue_mapping_error(). Prototype was for virtqueue_map_mapping_error() instead The kernel-doc block for virtqueue_map_free_coherent() omitted the @vaddr parameter, and the kernel-doc header for virtqueue_map_mapping_error() used the wrong function name (virtqueue_mapping_error) instead of the actual function name. This change updates: - the function name in the comment to virtqueue_map_mapping_error() - adds the missing @vaddr description in the comment for virtqueue_map_free_coherent() Fixes: b41cb3bcf67f ("virtio: rename dma helpers") Signed-off-by: Kriish Sharma Reviewed-by: Chaitanya Kulkarni Signed-off-by: Michael S. Tsirkin Message-Id: <20251110202920.2250244-1-kriish.sharma2006@gmail.com> Signed-off-by: Sasha Levin

virtio_vdpa: fix misleading return in void function

2025-12-18T13:03:23+00:00

[ Upstream commit e40b6abe0b1247d43bc61942aa7534fca7209e44 ] virtio_vdpa_set_status() is declared as returning void, but it used "return vdpa_set_status()" Since vdpa_set_status() also returns void, the return statement is unnecessary and misleading. Remove it. Fixes: c043b4a8cf3b ("virtio: introduce a vDPA based transport") Signed-off-by: Alok Tiwari Message-Id: <20251001191653.1713923-1-alok.a.tiwari@oracle.com> Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang Signed-off-by: Sasha Levin

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2025-10-04T15:48:16+00:00

Pull virtio updates from Michael Tsirkin: "Just fixes and cleanups this time around. The mapping cleanups are preparing the ground for new features, though" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: virtio-vdpa: Drop redundant conversion to bool vduse: Use fixed 4KB bounce pages for non-4KB page size vduse: switch to use virtio map API instead of DMA API vdpa: introduce map ops vdpa: support virtio_map virtio: introduce map ops in virtio core virtio_ring: rename dma_handle to map_handle virtio: introduce virtio_map container union virtio: rename dma helpers virtio_ring: switch to use dma_{map|unmap}_page() virtio_ring: constify virtqueue pointer for DMA helpers virtio_balloon: Remove redundant __GFP_NOWARN vhost: vringh: Fix copy_to_iter return value check vhost: vringh: Modify the return value check

Merge tag 'dma-mapping-6.18-2025-09-30' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux

2025-10-04T00:41:12+00:00

Pull dma-mapping updates from Marek Szyprowski: - Refactoring of DMA mapping API to physical addresses as the primary interface instead of page+offset parameters This gets much closer to Matthew Wilcox's long term wish for struct-pageless IO to cacheable DRAM and is supporting memdesc project which seeks to substantially transform how struct page works. An advantage of this approach is the possibility of introducing DMA_ATTR_MMIO, which covers existing 'dma_map_resource' flow in the common paths, what in turn lets to use recently introduced dma_iova_link() API to map PCI P2P MMIO without creating struct page Developped by Leon Romanovsky and Jason Gunthorpe - Minor clean-up by Petr Tesarik and Qianfeng Rong * tag 'dma-mapping-6.18-2025-09-30' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: kmsan: fix missed kmsan_handle_dma() signature conversion mm/hmm: properly take MMIO path mm/hmm: migrate to physical address-based DMA mapping API dma-mapping: export new dma_*map_phys() interface xen: swiotlb: Open code map_resource callback dma-mapping: implement DMA_ATTR_MMIO for dma_(un)map_page_attrs() kmsan: convert kmsan_handle_dma to use physical addresses dma-mapping: convert dma_direct_*map_page to be phys_addr_t based iommu/dma: implement DMA_ATTR_MMIO for iommu_dma_(un)map_phys() iommu/dma: rename iommu_dma_*map_page to iommu_dma_*map_phys dma-mapping: rename trace_dma_*map_page to trace_dma_*map_phys dma-debug: refactor to use physical addresses for page mapping iommu/dma: implement DMA_ATTR_MMIO for dma_iova_link(). dma-mapping: introduce new DMA attribute to indicate MMIO memory swiotlb: Remove redundant __GFP_NOWARN dma-direct: clean up the logic in __dma_direct_alloc_pages()

virtio-vdpa: Drop redundant conversion to bool

2025-10-01T11:24:55+00:00

The result of integer comparison already evaluates to bool. No need for explicit conversion. Signed-off-by: Xichao Zhao Message-Id: <20250818102848.578875-1-zhao.xichao@vivo.com> Signed-off-by: Michael S. Tsirkin

vdpa: introduce map ops

2025-10-01T11:24:55+00:00

Virtio core allows the transport to provide device or transport specific mapping functions. This patch adds this support to vDPA. We can simply do this by allowing the vDPA parent to register a virtio_map_ops. Reviewed-by: Christoph Hellwig Signed-off-by: Jason Wang Message-Id: <20250924070045.10361-2-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Eugenio Pérez