linux/drivers/vfio, branch v6.7

vfio/pds: Fix possible sleep while in atomic context

2023-11-27T16:29:03Z

The driver could possibly sleep while in atomic context resulting in the following call trace while CONFIG_DEBUG_ATOMIC_SLEEP=y is set: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:283 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2817, name: bash preempt_count: 1, expected: 0 RCU nest depth: 0, expected: 0 Call Trace: dump_stack_lvl+0x36/0x50 __might_resched+0x123/0x170 mutex_lock+0x1e/0x50 pds_vfio_put_lm_file+0x1e/0xa0 [pds_vfio_pci] pds_vfio_put_save_file+0x19/0x30 [pds_vfio_pci] pds_vfio_state_mutex_unlock+0x2e/0x80 [pds_vfio_pci] pci_reset_function+0x4b/0x70 reset_store+0x5b/0xa0 kernfs_fop_write_iter+0x137/0x1d0 vfs_write+0x2de/0x410 ksys_write+0x5d/0xd0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 This can happen if pds_vfio_put_restore_file() and/or pds_vfio_put_save_file() grab the mutex_lock(&lm_file->lock) while the spin_lock(&pds_vfio->reset_lock) is held, which can happen during while calling pds_vfio_state_mutex_unlock(). Fix this by changing the reset_lock to reset_mutex so there are no such conerns. Also, make sure to destroy the reset_mutex in the driver specific VFIO device release function. This also fixes a spinlock bad magic BUG that was caused by not calling spinlock_init() on the reset_lock. Since, the lock is being changed to a mutex, make sure to call mutex_init() on it. Reported-by: Dan Carpenter Closes: https://lore.kernel.org/kvm/1f9bc27b-3de9-4891-9687-ba2820c1b390@moroto.mountain/ Fixes: bb500dbe2ac6 ("vfio/pds: Add VFIO live migration support") Signed-off-by: Brett Creeley Reviewed-by: Shannon Nelson Link: https://lore.kernel.org/r/20231122192532.25791-3-brett.creeley@amd.com Signed-off-by: Alex Williamson

vfio/pds: Fix mutex lock->magic != lock warning

2023-11-27T16:29:03Z

The following BUG was found when running on a kernel with CONFIG_DEBUG_MUTEXES=y set: DEBUG_LOCKS_WARN_ON(lock->magic != lock) RIP: 0010:mutex_trylock+0x10d/0x120 Call Trace: ? __warn+0x85/0x140 ? mutex_trylock+0x10d/0x120 ? report_bug+0xfc/0x1e0 ? handle_bug+0x3f/0x70 ? exc_invalid_op+0x17/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? mutex_trylock+0x10d/0x120 ? mutex_trylock+0x10d/0x120 pds_vfio_reset+0x3a/0x60 [pds_vfio_pci] pci_reset_function+0x4b/0x70 reset_store+0x5b/0xa0 kernfs_fop_write_iter+0x137/0x1d0 vfs_write+0x2de/0x410 ksys_write+0x5d/0xd0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 As shown, lock->magic != lock. This is because mutex_init(&pds_vfio->state_mutex) is called in the VFIO open path. So, if a reset is initiated before the VFIO device is opened the mutex will have never been initialized. Fix this by calling mutex_init(&pds_vfio->state_mutex) in the VFIO init path. Also, don't destroy the mutex on close because the device may be re-opened, which would cause mutex to be uninitialized. Fix this by implementing a driver specific vfio_device_ops.release callback that destroys the mutex before calling vfio_pci_core_release_dev(). Fixes: bb500dbe2ac6 ("vfio/pds: Add VFIO live migration support") Signed-off-by: Brett Creeley Reviewed-by: Shannon Nelson Link: https://lore.kernel.org/r/20231122192532.25791-2-brett.creeley@amd.com Signed-off-by: Alex Williamson

Merge tag 'char-misc-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2023-11-04T00:51:08Z

Pull char/misc updates from Greg KH: "Here is the big set of char/misc and other small driver subsystem changes for 6.7-rc1. Included in here are: - IIO subsystem driver updates and additions (largest part of this pull request) - FPGA subsystem driver updates - Counter subsystem driver updates - ICC subsystem driver updates - extcon subsystem driver updates - mei driver updates and additions - nvmem subsystem driver updates and additions - comedi subsystem dependency fixes - parport driver fixups - cdx subsystem driver and core updates - splice support for /dev/zero and /dev/full - other smaller driver cleanups All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (326 commits) cdx: add sysfs for subsystem, class and revision cdx: add sysfs for bus reset cdx: add support for bus enable and disable cdx: Register cdx bus as a device on cdx subsystem cdx: Create symbol namespaces for cdx subsystem cdx: Introduce lock to protect controller ops cdx: Remove cdx controller list from cdx bus system dts: ti: k3-am625-beagleplay: Add beaglecc1352 greybus: Add BeaglePlay Linux Driver dt-bindings: net: Add ti,cc1352p7 dt-bindings: eeprom: at24: allow NVMEM cells based on old syntax dt-bindings: nvmem: SID: allow NVMEM cells based on old syntax Revert "nvmem: add new config option" MAINTAINERS: coresight: Add missing Coresight files misc: pci_endpoint_test: Add deviceID for J721S2 PCIe EP device support firmware: xilinx: Move EXPORT_SYMBOL_GPL next to zynqmp_pm_feature definition uacce: make uacce_class constant ocxl: make ocxl_class constant cxl: make cxl_class constant misc: phantom: make phantom_class constant ...

Merge tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd

2023-11-02T02:44:56Z

Pull iommufd updates from Jason Gunthorpe: "This brings three new iommufd capabilities: - Dirty tracking for DMA. AMD/ARM/Intel CPUs can now record if a DMA writes to a page in the IOPTEs within the IO page table. This can be used to generate a record of what memory is being dirtied by DMA activities during a VM migration process. A VMM like qemu will combine the IOMMU dirty bits with the CPU's dirty log to determine what memory to transfer. VFIO already has a DMA dirty tracking framework that requires PCI devices to implement tracking HW internally. The iommufd version provides an alternative that the VMM can select, if available. The two are designed to have very similar APIs. - Userspace controlled attributes for hardware page tables (HWPT/iommu_domain). There are currently a few generic attributes for HWPTs (support dirty tracking, and parent of a nest). This is an entry point for the userspace iommu driver to control the HW in detail. - Nested translation support for HWPTs. This is a 2D translation scheme similar to the CPU where a DMA goes through a first stage to determine an intermediate address which is then translated trough a second stage to a physical address. Like for CPU translation the first stage table would exist in VM controlled memory and the second stage is in the kernel and matches the VM's guest to physical map. As every IOMMU has a unique set of parameter to describe the S1 IO page table and its associated parameters the userspace IOMMU driver has to marshal the information into the correct format. This is 1/3 of the feature, it allows creating the nested translation and binding it to VFIO devices, however the API to support IOTLB and ATC invalidation of the stage 1 io page table, and forwarding of IO faults are still in progress. The series includes AMD and Intel support for dirty tracking. Intel support for nested translation. Along the way are a number of internal items: - New iommu core items: ops->domain_alloc_user(), ops->set_dirty_tracking, ops->read_and_clear_dirty(), IOMMU_DOMAIN_NESTED, and iommu_copy_struct_from_user - UAF fix in iopt_area_split() - Spelling fixes and some test suite improvement" * tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (52 commits) iommufd: Organize the mock domain alloc functions closer to Joerg's tree iommufd/selftest: Fix page-size check in iommufd_test_dirty() iommufd: Add iopt_area_alloc() iommufd: Fix missing update of domains_itree after splitting iopt_area iommu/vt-d: Disallow read-only mappings to nest parent domain iommu/vt-d: Add nested domain allocation iommu/vt-d: Set the nested domain to a device iommu/vt-d: Make domain attach helpers to be extern iommu/vt-d: Add helper to setup pasid nested translation iommu/vt-d: Add helper for nested domain allocation iommu/vt-d: Extend dmar_domain to support nested domain iommufd: Add data structure for Intel VT-d stage-1 domain allocation iommu/vt-d: Enhance capability check for nested parent domain allocation iommufd/selftest: Add coverage for IOMMU_HWPT_ALLOC with nested HWPTs iommufd/selftest: Add nested domain allocation for mock domain iommu: Add iommu_copy_struct_from_user helper iommufd: Add a nested HW pagetable object iommu: Pass in parent domain with user_data to domain_alloc_user op iommufd: Share iommufd_hwpt_alloc with IOMMUFD_OBJ_HWPT_NESTED iommufd: Derive iommufd_hwpt_paging from iommufd_hw_pagetable ...

cdx: Create symbol namespaces for cdx subsystem

2023-10-27T11:23:24Z

Create CDX_BUS and CDX_BUS_CONTROLLER symbol namespace for cdx bus subsystem. CDX controller modules are required to import symbols from CDX_BUS_CONTROLLER namespace and other than controller modules to import from CDX_BUS namespace. Signed-off-by: Abhijit Gangurde Link: https://lore.kernel.org/r/20231017160505.10640-4-abhijit.gangurde@amd.com Signed-off-by: Greg Kroah-Hartman

iommufd/iova_bitmap: Move symbols to IOMMUFD namespace

2023-10-24T14:58:42Z

Have the IOVA bitmap exported symbols adhere to the IOMMUFD symbol export convention i.e. using the IOMMUFD namespace. In doing so, import the namespace in the current users. This means VFIO and the vfio-pci drivers that use iova_bitmap_set(). Link: https://lore.kernel.org/r/20231024135109.73787-4-joao.m.martins@oracle.com Suggested-by: Jason Gunthorpe Signed-off-by: Joao Martins Reviewed-by: Jason Gunthorpe Reviewed-by: Brett Creeley Reviewed-by: Kevin Tian Reviewed-by: Alex Williamson Signed-off-by: Jason Gunthorpe

vfio: Move iova_bitmap into iommufd

2023-10-24T14:58:42Z

Both VFIO and IOMMUFD will need iova bitmap for storing dirties and walking the user bitmaps, so move to the common dependency into IOMMUFD. In doing so, create the symbol IOMMUFD_DRIVER which designates the builtin code that will be used by drivers when selected. Today this means MLX5_VFIO_PCI and PDS_VFIO_PCI. IOMMU drivers will do the same (in future patches) when supporting dirty tracking and select IOMMUFD_DRIVER accordingly. Given that the symbol maybe be disabled, add header definitions in iova_bitmap.h for when IOMMUFD_DRIVER=n Link: https://lore.kernel.org/r/20231024135109.73787-3-joao.m.martins@oracle.com Signed-off-by: Joao Martins Reviewed-by: Jason Gunthorpe Reviewed-by: Brett Creeley Reviewed-by: Kevin Tian Reviewed-by: Alex Williamson Signed-off-by: Jason Gunthorpe

vfio/iova_bitmap: Export more API symbols

2023-10-24T14:58:42Z

In preparation to move iova_bitmap into iommufd, export the rest of API symbols that will be used in what could be used by modules, namely: iova_bitmap_alloc iova_bitmap_free iova_bitmap_for_each Link: https://lore.kernel.org/r/20231024135109.73787-2-joao.m.martins@oracle.com Suggested-by: Alex Williamson Signed-off-by: Joao Martins Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Reviewed-by: Alex Williamson Signed-off-by: Jason Gunthorpe

vfio: Fix smatch errors in vfio_combine_iova_ranges()

2023-10-09T21:56:09Z

smatch reports: vfio_combine_iova_ranges() error: uninitialized symbol 'last'. vfio_combine_iova_ranges() error: potentially dereferencing uninitialized 'comb_end'. vfio_combine_iova_ranges() error: potentially dereferencing uninitialized 'comb_start'. These errors are only reachable via invalid input, in the case of @last when we receive an empty rb-tree or for @comb_{start,end} if the rb-tree is empty or otherwise fails to produce a second node that reduces the gap. Add tests with warnings for these cases. Reported-by: Cong Liu Link: https://lore.kernel.org/all/20230920095532.88135-1-liucong2@kylinos.cn Reviewed-by: Jason Gunthorpe Reviewed-by: Brett Creeley Link: https://lore.kernel.org/r/20231002224325.3150842-1-alex.williamson@redhat.com Signed-off-by: Alex Williamson

vfio/cdx: Add parentheses between bitwise AND expression and logical NOT

2023-10-03T17:40:49Z

When building with clang, there is a warning (or error with CONFIG_WERROR=y) due to a bitwise AND and logical NOT in vfio_cdx_bm_ctrl(): drivers/vfio/cdx/main.c:77:6: error: logical not is only applied to the left hand side of this bitwise operator [-Werror,-Wlogical-not-parentheses] 77 | if (!vdev->flags & BME_SUPPORT) | ^ ~ drivers/vfio/cdx/main.c:77:6: note: add parentheses after the '!' to evaluate the bitwise operator first 77 | if (!vdev->flags & BME_SUPPORT) | ^ | ( ) drivers/vfio/cdx/main.c:77:6: note: add parentheses around left hand side expression to silence this warning 77 | if (!vdev->flags & BME_SUPPORT) | ^ | ( ) 1 error generated. Add the parentheses as suggested in the first note, which is clearly what was intended here. Closes: https://github.com/ClangBuiltLinux/linux/issues/1939 Fixes: 8a97ab9b8b31 ("vfio-cdx: add bus mastering device feature support") Signed-off-by: Nathan Chancellor Reviewed-by: Philippe Mathieu-Daudé Acked-by: Nikhil Agarwal Reviewed-by: Nick Desaulniers Link: https://lore.kernel.org/r/20231002-vfio-cdx-logical-not-parentheses-v1-1-a8846c7adfb6@kernel.org Signed-off-by: Alex Williamson