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path: root/drivers/vfio/pci/vfio_pci.c
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2021-08-26vfio/pci: Introduce vfio_pci_core.koMax Gurtovoy1-11/+3
Now that vfio_pci has been split into two source modules, one focusing on the "struct pci_driver" (vfio_pci.c) and a toolbox library of code (vfio_pci_core.c), complete the split and move them into two different kernel modules. As before vfio_pci.ko continues to present the same interface under sysfs and this change will have no functional impact. Splitting into another module and adding exports allows creating new HW specific VFIO PCI drivers that can implement device specific functionality, such as VFIO migration interfaces or specialized device requirements. Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Yishai Hadas <yishaih@nvidia.com> Link: https://lore.kernel.org/r/20210826103912.128972-14-yishaih@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-26PCI / VFIO: Add 'override_only' support for VFIO PCI sub systemMax Gurtovoy1-1/+8
Expose an 'override_only' helper macro (i.e. PCI_DRIVER_OVERRIDE_DEVICE_VFIO) for VFIO PCI sub system and add the required code to prefix its matching entries with "vfio_" in modules.alias file. It allows VFIO device drivers to include match entries in the modules.alias file produced by kbuild that are not used for normal driver autoprobing and module autoloading. Drivers using these match entries can be connected to the PCI device manually, by userspace, using the existing driver_override sysfs. For example the resulting modules.alias may have: alias pci:v000015B3d00001021sv*sd*bc*sc*i* mlx5_core alias vfio_pci:v000015B3d00001021sv*sd*bc*sc*i* mlx5_vfio_pci alias vfio_pci:v*d*sv*sd*bc*sc*i* vfio_pci In this example mlx5_core and mlx5_vfio_pci match to the same PCI device. The kernel will autoload and autobind to mlx5_core but the kernel and udev mechanisms will ignore mlx5_vfio_pci. When userspace wants to change a device to the VFIO subsystem it can implement a generic algorithm: 1) Identify the sysfs path to the device: /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0 2) Get the modalias string from the kernel: $ cat /sys/bus/pci/devices/0000:01:00.0/modalias pci:v000015B3d00001021sv000015B3sd00000001bc02sc00i00 3) Prefix it with vfio_: vfio_pci:v000015B3d00001021sv000015B3sd00000001bc02sc00i00 4) Search modules.alias for the above string and select the entry that has the fewest *'s: alias vfio_pci:v000015B3d00001021sv*sd*bc*sc*i* mlx5_vfio_pci 5) modprobe the matched module name: $ modprobe mlx5_vfio_pci 6) cat the matched module name to driver_override: echo mlx5_vfio_pci > /sys/bus/pci/devices/0000:01:00.0/driver_override 7) unbind device from original module echo 0000:01:00.0 > /sys/bus/pci/devices/0000:01:00.0/driver/unbind 8) probe PCI drivers (or explicitly bind to mlx5_vfio_pci) echo 0000:01:00.0 > /sys/bus/pci/drivers_probe The algorithm is independent of bus type. In future the other buses with VFIO device drivers, like platform and ACPI, can use this algorithm as well. This patch is the infrastructure to provide the information in the modules.alias to userspace. Convert the only VFIO pci_driver which results in one new line in the modules.alias: alias vfio_pci:v*d*sv*sd*bc*sc*i* vfio_pci Later series introduce additional HW specific VFIO PCI drivers, such as mlx5_vfio_pci. Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> # for pci.h Signed-off-by: Yishai Hadas <yishaih@nvidia.com> Link: https://lore.kernel.org/r/20210826103912.128972-11-yishaih@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-26vfio/pci: Move module parameters to vfio_pci.cYishai Hadas1-0/+23
This is a preparation before splitting vfio_pci.ko to 2 modules. As module parameters are a kind of uAPI they need to stay on vfio_pci.ko to avoid a user visible impact. For now continue to keep the implementation of these options in vfio_pci_core.c. Arguably they are vfio_pci functionality, but further splitting of vfio_pci_core.c will be better done in another series Signed-off-by: Yishai Hadas <yishaih@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20210826103912.128972-9-yishaih@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-26vfio/pci: Move igd initialization to vfio_pci.cMax Gurtovoy1-1/+28
igd is related to the vfio_pci pci_driver implementation, move it out of vfio_pci_core.c. This is preparation for splitting vfio_pci.ko into 2 drivers. Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Yishai Hadas <yishaih@nvidia.com> Link: https://lore.kernel.org/r/20210826103912.128972-8-yishaih@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-26vfio/pci: Split the pci_driver code out of vfio_pci_core.cMax Gurtovoy1-0/+223
Split the vfio_pci driver into two logical parts, the 'struct pci_driver' (vfio_pci.c) which implements "Generic VFIO support for any PCI device" and a library of code (vfio_pci_core.c) that helps implementing a struct vfio_device on top of a PCI device. vfio_pci.ko continues to present the same interface under sysfs and this change should have no functional impact. Following patches will turn vfio_pci and vfio_pci_core into a separate module. This is a preparation for allowing another module to provide the pci_driver and allow that module to customize how VFIO is setup, inject its own operations, and easily extend vendor specific functionality. At this point the vfio_pci_core still contains a lot of vfio_pci functionality mixed into it. Following patches will move more of the large scale items out, but another cleanup series will be needed to get everything. Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Yishai Hadas <yishaih@nvidia.com> Link: https://lore.kernel.org/r/20210826103912.128972-7-yishaih@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-26vfio/pci: Rename vfio_pci.c to vfio_pci_core.cMax Gurtovoy1-2320/+0
This is a preparation patch for separating the vfio_pci driver to a subsystem driver and a generic pci driver. This patch doesn't change any logic. Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Yishai Hadas <yishaih@nvidia.com> Link: https://lore.kernel.org/r/20210826103912.128972-2-yishaih@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11vfio/pci: Reorganize VFIO_DEVICE_PCI_HOT_RESET to use the device setJason Gunthorpe1-124/+89
Like vfio_pci_dev_set_try_reset() this code wants to reset all of the devices in the "reset group" which is the same membership as the device set. Instead of trying to reconstruct the device set from the PCI list go directly from the device set's device list to execute the reset. The same basic structure as vfio_pci_dev_set_try_reset() is used. The 'vfio_devices' struct is replaced with the device set linked list and we simply sweep it multiple times under the lock. This eliminates a memory allocation and get/put traffic and another improperly locked test of pci_dev_driver(). Reviewed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Link: https://lore.kernel.org/r/10-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11vfio/pci: Change vfio_pci_try_bus_reset() to use the dev_setJason Gunthorpe1-92/+82
vfio_pci_try_bus_reset() is triggering a reset of the entire_dev set if any device within it has accumulated a needs_reset. This reset can only be done once all of the drivers operating the PCI devices to be reset are in a known safe state. Make this clearer by directly operating on the dev_set instead of the vfio_pci_device. Rename the function to vfio_pci_dev_set_try_reset(). Use the device list inside the dev_set to check that all drivers are in a safe state instead of working backwards from the pci_device. The dev_set->lock directly prevents devices from joining/leaving the set, or changing their state, which further implies the pci_device cannot change drivers or that the vfio_device be freed, eliminating the need for get/put's. If a pci_device to be reset is not in the dev_set then the reset cannot be used as we can't know what the state of that driver is. Directly measure this by checking that every pci_device is in the dev_set - which effectively proves that VFIO drivers are attached to everything. Remove the odd interaction around vfio_pci_set_power_state() - have the only caller avoid its redundant vfio_pci_set_power_state() instead of avoiding it inside vfio_pci_dev_set_try_reset(). This restructuring corrects a call to pci_dev_driver() without holding the device_lock() and removes a hard wiring to &vfio_pci_driver. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Link: https://lore.kernel.org/r/9-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11vfio/pci: Move to the device set infrastructureYishai Hadas1-125/+37
PCI wants to have the usual open/close_device() logic with the slight twist that the open/close_device() must be done under a singelton lock shared by all of the vfio_devices that are in the PCI "reset group". The reset group, and thus the device set, is determined by what devices pci_reset_bus() touches, which is either the entire bus or only the slot. Rely on the core code to do everything reflck was doing and delete reflck entirely. Signed-off-by: Yishai Hadas <yishaih@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Link: https://lore.kernel.org/r/8-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11vfio: Introduce a vfio_uninit_group_dev() API callMax Gurtovoy1-2/+4
This pairs with vfio_init_group_dev() and allows undoing any state that is stored in the vfio_device unrelated to registration. Add appropriately placed calls to all the drivers. The following patch will use this to add pre-registration state for the device set. Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/3-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-06-30vfio/pci: Handle concurrent vma faultsAlex Williamson1-8/+21
io_remap_pfn_range() will trigger a BUG_ON if it encounters a populated pte within the mapping range. This can occur because we map the entire vma on fault and multiple faults can be blocked behind the vma_lock. This leads to traces like the one reported below. We can use our vma_list to test whether a given vma is mapped to avoid this issue. [ 1591.733256] kernel BUG at mm/memory.c:2177! [ 1591.739515] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [ 1591.747381] Modules linked in: vfio_iommu_type1 vfio_pci vfio_virqfd vfio pv680_mii(O) [ 1591.760536] CPU: 2 PID: 227 Comm: lcore-worker-2 Tainted: G O 5.11.0-rc3+ #1 [ 1591.770735] Hardware name: , BIOS HixxxxFPGA 1P B600 V121-1 [ 1591.778872] pstate: 40400009 (nZcv daif +PAN -UAO -TCO BTYPE=--) [ 1591.786134] pc : remap_pfn_range+0x214/0x340 [ 1591.793564] lr : remap_pfn_range+0x1b8/0x340 [ 1591.799117] sp : ffff80001068bbd0 [ 1591.803476] x29: ffff80001068bbd0 x28: 0000042eff6f0000 [ 1591.810404] x27: 0000001100910000 x26: 0000001300910000 [ 1591.817457] x25: 0068000000000fd3 x24: ffffa92f1338e358 [ 1591.825144] x23: 0000001140000000 x22: 0000000000000041 [ 1591.832506] x21: 0000001300910000 x20: ffffa92f141a4000 [ 1591.839520] x19: 0000001100a00000 x18: 0000000000000000 [ 1591.846108] x17: 0000000000000000 x16: ffffa92f11844540 [ 1591.853570] x15: 0000000000000000 x14: 0000000000000000 [ 1591.860768] x13: fffffc0000000000 x12: 0000000000000880 [ 1591.868053] x11: ffff0821bf3d01d0 x10: ffff5ef2abd89000 [ 1591.875932] x9 : ffffa92f12ab0064 x8 : ffffa92f136471c0 [ 1591.883208] x7 : 0000001140910000 x6 : 0000000200000000 [ 1591.890177] x5 : 0000000000000001 x4 : 0000000000000001 [ 1591.896656] x3 : 0000000000000000 x2 : 0168044000000fd3 [ 1591.903215] x1 : ffff082126261880 x0 : fffffc2084989868 [ 1591.910234] Call trace: [ 1591.914837] remap_pfn_range+0x214/0x340 [ 1591.921765] vfio_pci_mmap_fault+0xac/0x130 [vfio_pci] [ 1591.931200] __do_fault+0x44/0x12c [ 1591.937031] handle_mm_fault+0xcc8/0x1230 [ 1591.942475] do_page_fault+0x16c/0x484 [ 1591.948635] do_translation_fault+0xbc/0xd8 [ 1591.954171] do_mem_abort+0x4c/0xc0 [ 1591.960316] el0_da+0x40/0x80 [ 1591.965585] el0_sync_handler+0x168/0x1b0 [ 1591.971608] el0_sync+0x174/0x180 [ 1591.978312] Code: eb1b027f 540000c0 f9400022 b4fffe02 (d4210000) Fixes: 11c4cd07ba11 ("vfio-pci: Fault mmaps to enable vma tracking") Reported-by: Zeng Tao <prime.zeng@hisilicon.com> Suggested-by: Zeng Tao <prime.zeng@hisilicon.com> Link: https://lore.kernel.org/r/162497742783.3883260.3282953006487785034.stgit@omen Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-06-24vfio: use the new pci_dev_trylock() helper to simplify try lockLuis Chamberlain1-7/+4
Use the new pci_dev_trylock() helper to simplify our locking. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20210623022824.308041-3-mcgrof@kernel.org Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-06-15vfio: centralize module refcount in subsystem layerMax Gurtovoy1-7/+0
Remove code duplication and move module refcounting to the subsystem module. Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Link: https://lore.kernel.org/r/20210518192133.59195-2-mgurtovoy@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-29Merge tag 'vfio-v5.13-rc1' of git://github.com/awilliam/linux-vfioLinus Torvalds1-134/+140
Pull VFIO updates from Alex Williamson: - Embed struct vfio_device into vfio driver structures (Jason Gunthorpe) - Make vfio_mdev type safe (Jason Gunthorpe) - Remove vfio-pci NVLink2 extensions for POWER9 (Christoph Hellwig) - Update vfio-pci IGD extensions for OpRegion 2.1+ (Fred Gao) - Various spelling/blank line fixes (Zhen Lei, Zhou Wang, Bhaskar Chowdhury) - Simplify unpin_pages error handling (Shenming Lu) - Fix i915 mdev Kconfig dependency (Arnd Bergmann) - Remove unused structure member (Keqian Zhu) * tag 'vfio-v5.13-rc1' of git://github.com/awilliam/linux-vfio: (43 commits) vfio/gvt: fix DRM_I915_GVT dependency on VFIO_MDEV vfio/iommu_type1: Remove unused pinned_page_dirty_scope in vfio_iommu vfio/mdev: Correct the function signatures for the mdev_type_attributes vfio/mdev: Remove kobj from mdev_parent_ops->create() vfio/gvt: Use mdev_get_type_group_id() vfio/gvt: Make DRM_I915_GVT depend on VFIO_MDEV vfio/mbochs: Use mdev_get_type_group_id() vfio/mdpy: Use mdev_get_type_group_id() vfio/mtty: Use mdev_get_type_group_id() vfio/mdev: Add mdev/mtype_get_type_group_id() vfio/mdev: Remove duplicate storage of parent in mdev_device vfio/mdev: Add missing error handling to dev_set_name() vfio/mdev: Reorganize mdev_device_create() vfio/mdev: Add missing reference counting to mdev_type vfio/mdev: Expose mdev_get/put_parent to mdev_private.h vfio/mdev: Use struct mdev_type in struct mdev_device vfio/mdev: Simplify driver registration vfio/mdev: Add missing typesafety around mdev_device vfio/mdev: Do not allow a mdev_type to have a NULL parent pointer vfio/mdev: Fix missing static's on MDEV_TYPE_ATTR's ...
2021-04-13vfio/pci: Add missing range check in vfio_pci_mmapChristian A. Ehrhardt1-1/+3
When mmaping an extra device region verify that the region index derived from the mmap offset is valid. Fixes: a15b1883fee1 ("vfio_pci: Allow mapping extra regions") Cc: stable@vger.kernel.org Signed-off-by: Christian A. Ehrhardt <lk@c--e.de> Message-Id: <20210412214124.GA241759@lisa.in-ulm.de> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06Merge branches 'v5.13/vfio/embed-vfio_device', 'v5.13/vfio/misc' and ↵Alex Williamson1-20/+1
'v5.13/vfio/nvlink' into v5.13/vfio/next Spelling fixes merged with file deletion. Conflicts: drivers/vfio/pci/vfio_pci_nvlink2.c Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06vfio: Remove device_data from the vfio bus driver APIJason Gunthorpe1-1/+1
There are no longer any users, so it can go away. Everything is using container_of now. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <14-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06vfio/pci: Replace uses of vfio_device_data() with container_ofJason Gunthorpe1-43/+24
This tidies a few confused places that think they can have a refcount on the vfio_device but the device_data could be NULL, that isn't possible by design. Most of the change falls out when struct vfio_devices is updated to just store the struct vfio_pci_device itself. This wasn't possible before because there was no easy way to get from the 'struct vfio_pci_device' to the 'struct vfio_device' to put back the refcount. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <13-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06vfio: Make vfio_device_ops pass a 'struct vfio_device *' instead of 'void *'Jason Gunthorpe1-18/+29
This is the standard kernel pattern, the ops associated with a struct get the struct pointer in for typesafety. The expected design is to use container_of to cleanly go from the subsystem level type to the driver level type without having any type erasure in a void *. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <12-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06vfio/pci: Use vfio_init/register/unregister_group_devJason Gunthorpe1-5/+5
pci already allocates a struct vfio_pci_device with exactly the same lifetime as vfio_device, switch to the new API and embed vfio_device in vfio_pci_device. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Liu Yi L <yi.l.liu@intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <9-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06vfio/pci: Re-order vfio_pci_probe()Jason Gunthorpe1-8/+9
vfio_add_group_dev() must be called only after all of the private data in vdev is fully setup and ready, otherwise there could be races with user space instantiating a device file descriptor and starting to call ops. For instance vfio_pci_reflck_attach() sets vdev->reflck and vfio_pci_open(), called by fops open, unconditionally derefs it, which will crash if things get out of order. Fixes: cc20d7999000 ("vfio/pci: Introduce VF token") Fixes: e309df5b0c9e ("vfio/pci: Parallelize device open and release") Fixes: 6eb7018705de ("vfio-pci: Move idle devices to D3hot power state") Fixes: ecaa1f6a0154 ("vfio-pci: Add VGA arbiter client") Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <8-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06vfio/pci: Move VGA and VF initialization to functionsJason Gunthorpe1-42/+74
vfio_pci_probe() is quite complicated, with optional VF and VGA sub components. Move these into clear init/uninit functions and have a linear flow in probe/remove. This fixes a few little buglets: - vfio_pci_remove() is in the wrong order, vga_client_register() removes a notifier and is after kfree(vdev), but the notifier refers to vdev, so it can use after free in a race. - vga_client_register() can fail but was ignored Organize things so destruction order is the reverse of creation order. Fixes: ecaa1f6a0154 ("vfio-pci: Add VGA arbiter client") Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <7-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06vfio/pci: remove vfio_pci_nvlink2Christoph Hellwig1-18/+0
This driver never had any open userspace (which for VFIO would include VM kernel drivers) that use it, and thus should never have been added by our normal userspace ABI rules. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Message-Id: <20210326061311.1497642-2-hch@lst.de> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06vfio/pci: Remove an unnecessary blank line in vfio_pci_enableZhou Wang1-1/+0
This blank line is unnecessary, so remove it. Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com> Message-Id: <1615808073-178604-1-git-send-email-wangzhou1@hisilicon.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06vfio: pci: Spello fix in the file vfio_pci.cBhaskar Chowdhury1-1/+1
s/permision/permission/ Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Message-Id: <20210314052925.3560-1-unixbhaskar@gmail.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-02-19vfio/pci: remove CONFIG_VFIO_PCI_ZDEV from KconfigMax Gurtovoy1-7/+5
In case we're running on s390 system always expose the capabilities for configuration of zPCI devices. In case we're running on different platform, continue as usual. Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-12-02vfio-pci: Use io_remap_pfn_range() for PCI IO memoryJason Gunthorpe1-2/+2
commit f8f6ae5d077a ("mm: always have io_remap_pfn_range() set pgprot_decrypted()") allows drivers using mmap to put PCI memory mapped BAR space into userspace to work correctly on AMD SME systems that default to all memory encrypted. Since vfio_pci_mmap_fault() is working with PCI memory mapped BAR space it should be calling io_remap_pfn_range() otherwise it will not work on SME systems. Fixes: 11c4cd07ba11 ("vfio-pci: Fault mmaps to enable vma tracking") Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Peter Xu <peterx@redhat.com> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-12-02vfio/pci: Move dummy_resources_list init in vfio_pci_probe()Eric Auger1-2/+1
In case an error occurs in vfio_pci_enable() before the call to vfio_pci_probe_mmaps(), vfio_pci_disable() will try to iterate on an uninitialized list and cause a kernel panic. Lets move to the initialization to vfio_pci_probe() to fix the issue. Signed-off-by: Eric Auger <eric.auger@redhat.com> Fixes: 05f0c03fbac1 ("vfio-pci: Allow to mmap sub-page MMIO BARs if the mmio page is exclusive") CC: Stable <stable@vger.kernel.org> # v4.7+ Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-11-03vfio/pci: Bypass IGD init in case of -ENODEVFred Gao1-1/+1
Bypass the IGD initialization when -ENODEV returns, that should be the case if opregion is not available for IGD or within discrete graphics device's option ROM, or host/lpc bridge is not found. Then use of -ENODEV here means no special device resources found which needs special care for VFIO, but we still allow other normal device resource access. Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Xiong Zhang <xiong.y.zhang@intel.com> Cc: Hang Yuan <hang.yuan@linux.intel.com> Cc: Stuart Summers <stuart.summers@intel.com> Signed-off-by: Fred Gao <fred.gao@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-10-22Merge tag 'vfio-v5.10-rc1' of git://github.com/awilliam/linux-vfioLinus Torvalds1-1/+37
Pull VFIO updates from Alex Williamson: - New fsl-mc vfio bus driver supporting userspace drivers of objects within NXP's DPAA2 architecture (Diana Craciun) - Support for exposing zPCI information on s390 (Matthew Rosato) - Fixes for "detached" VFs on s390 (Matthew Rosato) - Fixes for pin-pages and dma-rw accesses (Yan Zhao) - Cleanups and optimize vconfig regen (Zenghui Yu) - Fix duplicate irq-bypass token registration (Alex Williamson) * tag 'vfio-v5.10-rc1' of git://github.com/awilliam/linux-vfio: (30 commits) vfio iommu type1: Fix memory leak in vfio_iommu_type1_pin_pages vfio/pci: Clear token on bypass registration failure vfio/fsl-mc: fix the return of the uninitialized variable ret vfio/fsl-mc: Fix the dead code in vfio_fsl_mc_set_irq_trigger vfio/fsl-mc: Fixed vfio-fsl-mc driver compilation on 32 bit MAINTAINERS: Add entry for s390 vfio-pci vfio-pci/zdev: Add zPCI capabilities to VFIO_DEVICE_GET_INFO vfio/fsl-mc: Add support for device reset vfio/fsl-mc: Add read/write support for fsl-mc devices vfio/fsl-mc: trigger an interrupt via eventfd vfio/fsl-mc: Add irq infrastructure for fsl-mc devices vfio/fsl-mc: Added lock support in preparation for interrupt handling vfio/fsl-mc: Allow userspace to MMAP fsl-mc device MMIO regions vfio/fsl-mc: Implement VFIO_DEVICE_GET_REGION_INFO ioctl call vfio/fsl-mc: Implement VFIO_DEVICE_GET_INFO ioctl vfio/fsl-mc: Scan DPRC objects on vfio-fsl-mc driver bind vfio: Introduce capability definitions for VFIO_DEVICE_GET_INFO s390/pci: track whether util_str is valid in the zpci_dev s390/pci: stash version in the zpci_dev vfio/fsl-mc: Add VFIO framework skeleton for fsl-mc devices ...
2020-10-16mm: remove the now-unnecessary mmget_still_valid() hackJann Horn1-20/+18
The preceding patches have ensured that core dumping properly takes the mmap_lock. Thanks to that, we can now remove mmget_still_valid() and all its users. Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Hugh Dickins <hughd@google.com> Link: http://lkml.kernel.org/r/20200827114932.3572699-8-jannh@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-12Merge branches 'v5.10/vfio/fsl-mc-v6' and 'v5.10/vfio/zpci-info-v3' into ↵Alex Williamson1-0/+37
v5.10/vfio/next
2020-10-12vfio-pci/zdev: Add zPCI capabilities to VFIO_DEVICE_GET_INFOMatthew Rosato1-0/+37
Define a new configuration entry VFIO_PCI_ZDEV for VFIO/PCI. When this s390-only feature is configured we add capabilities to the VFIO_DEVICE_GET_INFO ioctl that describe features of the associated zPCI device and its underlying hardware. This patch is based on work previously done by Pierre Morel. Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-09-21vfio/pci: Remove redundant declaration of vfio_pci_driverZenghui Yu1-1/+0
It was added by commit 137e5531351d ("vfio/pci: Add sriov_configure support") but duplicates a forward declaration earlier in the file. Remove it. Signed-off-by: Zenghui Yu <yuzenghui@huawei.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-08-24treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva1-1/+1
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-07-27vfio/pci: Add QAT devices to denylistGiovanni Cabiddu1-0/+15
The current generation of Intel® QuickAssist Technology devices are not designed to run in an untrusted environment because of the following issues reported in the document "Intel® QuickAssist Technology (Intel® QAT) Software for Linux" (document number 336211-014): QATE-39220 - GEN - Intel® QAT API submissions with bad addresses that trigger DMA to invalid or unmapped addresses can cause a platform hang QATE-7495 - GEN - An incorrectly formatted request to Intel® QAT can hang the entire Intel® QAT Endpoint The document is downloadable from https://01.org/intel-quickassist-technology at the following link: https://01.org/sites/default/files/downloads/336211-014-qatforlinux-releasenotes-hwv1.7_0.pdf This patch adds the following QAT devices to the denylist: DH895XCC, C3XXX and C62X. Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com> Reviewed-by: Fiona Trahe <fiona.trahe@intel.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-07-27vfio/pci: Add device denylistGiovanni Cabiddu1-0/+33
Add denylist of devices that by default are not probed by vfio-pci. Devices in this list may be susceptible to untrusted application, even if the IOMMU is enabled. To be accessed via vfio-pci, the user has to explicitly disable the denylist. The denylist can be disabled via the module parameter disable_denylist. Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Fiona Trahe <fiona.trahe@intel.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-07-27vfio/pci: Hold igate across releasing eventfd contextsAlex Williamson1-3/+1
No need to release and immediately re-acquire igate while clearing out the eventfd ctxs. Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-07-27vfio/pci: Add Intel X550 to hidden INTx devicesAlex Williamson1-0/+2
Intel document 333717-008, "Intel® Ethernet Controller X550 Specification Update", version 2.7, dated June 2020, includes errata #22, added in version 2.1, May 2016, indicating X550 NICs suffer from the same implementation deficiency as the 700-series NICs: "The Interrupt Status bit in the Status register of the PCIe configuration space is not implemented and is not set as described in the PCIe specification." Without the interrupt status bit, vfio-pci cannot determine when these devices signal INTx. They are therefore added to the nointx quirk. Cc: Jesse Brandeburg <jesse.brandeburg@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-07-17vfio/pci: fix racy on error and request eventfd ctxZeng Tao1-0/+5
The vfio_pci_release call will free and clear the error and request eventfd ctx while these ctx could be in use at the same time in the function like vfio_pci_request, and it's expected to protect them under the vdev->igate mutex, which is missing in vfio_pci_release. This issue is introduced since commit 1518ac272e78 ("vfio/pci: fix memory leaks of eventfd ctx"),and since commit 5c5866c593bb ("vfio/pci: Clear error and request eventfd ctx after releasing"), it's very easily to trigger the kernel panic like this: [ 9513.904346] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 [ 9513.913091] Mem abort info: [ 9513.915871] ESR = 0x96000006 [ 9513.918912] EC = 0x25: DABT (current EL), IL = 32 bits [ 9513.924198] SET = 0, FnV = 0 [ 9513.927238] EA = 0, S1PTW = 0 [ 9513.930364] Data abort info: [ 9513.933231] ISV = 0, ISS = 0x00000006 [ 9513.937048] CM = 0, WnR = 0 [ 9513.940003] user pgtable: 4k pages, 48-bit VAs, pgdp=0000007ec7d12000 [ 9513.946414] [0000000000000008] pgd=0000007ec7d13003, p4d=0000007ec7d13003, pud=0000007ec728c003, pmd=0000000000000000 [ 9513.956975] Internal error: Oops: 96000006 [#1] PREEMPT SMP [ 9513.962521] Modules linked in: vfio_pci vfio_virqfd vfio_iommu_type1 vfio hclge hns3 hnae3 [last unloaded: vfio_pci] [ 9513.972998] CPU: 4 PID: 1327 Comm: bash Tainted: G W 5.8.0-rc4+ #3 [ 9513.980443] Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V3.B270.01 05/08/2020 [ 9513.989274] pstate: 80400089 (Nzcv daIf +PAN -UAO BTYPE=--) [ 9513.994827] pc : _raw_spin_lock_irqsave+0x48/0x88 [ 9513.999515] lr : eventfd_signal+0x6c/0x1b0 [ 9514.003591] sp : ffff800038a0b960 [ 9514.006889] x29: ffff800038a0b960 x28: ffff007ef7f4da10 [ 9514.012175] x27: ffff207eefbbfc80 x26: ffffbb7903457000 [ 9514.017462] x25: ffffbb7912191000 x24: ffff007ef7f4d400 [ 9514.022747] x23: ffff20be6e0e4c00 x22: 0000000000000008 [ 9514.028033] x21: 0000000000000000 x20: 0000000000000000 [ 9514.033321] x19: 0000000000000008 x18: 0000000000000000 [ 9514.038606] x17: 0000000000000000 x16: ffffbb7910029328 [ 9514.043893] x15: 0000000000000000 x14: 0000000000000001 [ 9514.049179] x13: 0000000000000000 x12: 0000000000000002 [ 9514.054466] x11: 0000000000000000 x10: 0000000000000a00 [ 9514.059752] x9 : ffff800038a0b840 x8 : ffff007ef7f4de60 [ 9514.065038] x7 : ffff007fffc96690 x6 : fffffe01faffb748 [ 9514.070324] x5 : 0000000000000000 x4 : 0000000000000000 [ 9514.075609] x3 : 0000000000000000 x2 : 0000000000000001 [ 9514.080895] x1 : ffff007ef7f4d400 x0 : 0000000000000000 [ 9514.086181] Call trace: [ 9514.088618] _raw_spin_lock_irqsave+0x48/0x88 [ 9514.092954] eventfd_signal+0x6c/0x1b0 [ 9514.096691] vfio_pci_request+0x84/0xd0 [vfio_pci] [ 9514.101464] vfio_del_group_dev+0x150/0x290 [vfio] [ 9514.106234] vfio_pci_remove+0x30/0x128 [vfio_pci] [ 9514.111007] pci_device_remove+0x48/0x108 [ 9514.115001] device_release_driver_internal+0x100/0x1b8 [ 9514.120200] device_release_driver+0x28/0x38 [ 9514.124452] pci_stop_bus_device+0x68/0xa8 [ 9514.128528] pci_stop_and_remove_bus_device+0x20/0x38 [ 9514.133557] pci_iov_remove_virtfn+0xb4/0x128 [ 9514.137893] sriov_disable+0x3c/0x108 [ 9514.141538] pci_disable_sriov+0x28/0x38 [ 9514.145445] hns3_pci_sriov_configure+0x48/0xb8 [hns3] [ 9514.150558] sriov_numvfs_store+0x110/0x198 [ 9514.154724] dev_attr_store+0x44/0x60 [ 9514.158373] sysfs_kf_write+0x5c/0x78 [ 9514.162018] kernfs_fop_write+0x104/0x210 [ 9514.166010] __vfs_write+0x48/0x90 [ 9514.169395] vfs_write+0xbc/0x1c0 [ 9514.172694] ksys_write+0x74/0x100 [ 9514.176079] __arm64_sys_write+0x24/0x30 [ 9514.179987] el0_svc_common.constprop.4+0x110/0x200 [ 9514.184842] do_el0_svc+0x34/0x98 [ 9514.188144] el0_svc+0x14/0x40 [ 9514.191185] el0_sync_handler+0xb0/0x2d0 [ 9514.195088] el0_sync+0x140/0x180 [ 9514.198389] Code: b9001020 d2800000 52800022 f9800271 (885ffe61) [ 9514.204455] ---[ end trace 648de00c8406465f ]--- [ 9514.212308] note: bash[1327] exited with preempt_count 1 Cc: Qian Cai <cai@lca.pw> Cc: Alex Williamson <alex.williamson@redhat.com> Fixes: 1518ac272e78 ("vfio/pci: fix memory leaks of eventfd ctx") Signed-off-by: Zeng Tao <prime.zeng@hisilicon.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-06-18vfio/pci: Clear error and request eventfd ctx after releasingAlex Williamson1-2/+6
The next use of the device will generate an underflow from the stale reference. Cc: Qian Cai <cai@lca.pw> Fixes: 1518ac272e78 ("vfio/pci: fix memory leaks of eventfd ctx") Reported-by: Daniel Wagner <dwagner@suse.de> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Tested-by: Daniel Wagner <dwagner@suse.de> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-06-09mmap locking API: convert mmap_sem commentsMichel Lespinasse1-7/+7
Convert comments that reference mmap_sem to reference mmap_lock instead. [akpm@linux-foundation.org: fix up linux-next leftovers] [akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil] [akpm@linux-foundation.org: more linux-next fixups, per Michel] Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09mmap locking API: convert mmap_sem call sites missed by coccinelleMichel Lespinasse1-4/+4
Convert the last few remaining mmap_sem rwsem calls to use the new mmap locking API. These were missed by coccinelle for some reason (I think coccinelle does not support some of the preprocessor constructs in these files ?) [akpm@linux-foundation.org: convert linux-next leftovers] [akpm@linux-foundation.org: more linux-next leftovers] [akpm@linux-foundation.org: more linux-next leftovers] Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-6-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-26Merge branches 'v5.8/vfio/alex-block-mmio-v3', 'v5.8/vfio/alex-zero-cap-v2' ↵Alex Williamson1-26/+327
and 'v5.8/vfio/qian-leak-fixes' into v5.8/vfio/next
2020-05-26vfio/pci: fix memory leaks of eventfd ctxQian Cai1-0/+4
Finished a qemu-kvm (-device vfio-pci,host=0001:01:00.0) triggers a few memory leaks after a while because vfio_pci_set_ctx_trigger_single() calls eventfd_ctx_fdget() without the matching eventfd_ctx_put() later. Fix it by calling eventfd_ctx_put() for those memory in vfio_pci_release() before vfio_device_release(). unreferenced object 0xebff008981cc2b00 (size 128): comm "qemu-kvm", pid 4043, jiffies 4294994816 (age 9796.310s) hex dump (first 32 bytes): 01 00 00 00 6b 6b 6b 6b 00 00 00 00 ad 4e ad de ....kkkk.....N.. ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff ....kkkk........ backtrace: [<00000000917e8f8d>] slab_post_alloc_hook+0x74/0x9c [<00000000df0f2aa2>] kmem_cache_alloc_trace+0x2b4/0x3d4 [<000000005fcec025>] do_eventfd+0x54/0x1ac [<0000000082791a69>] __arm64_sys_eventfd2+0x34/0x44 [<00000000b819758c>] do_el0_svc+0x128/0x1dc [<00000000b244e810>] el0_sync_handler+0xd0/0x268 [<00000000d495ef94>] el0_sync+0x164/0x180 unreferenced object 0x29ff008981cc4180 (size 128): comm "qemu-kvm", pid 4043, jiffies 4294994818 (age 9796.290s) hex dump (first 32 bytes): 01 00 00 00 6b 6b 6b 6b 00 00 00 00 ad 4e ad de ....kkkk.....N.. ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff ....kkkk........ backtrace: [<00000000917e8f8d>] slab_post_alloc_hook+0x74/0x9c [<00000000df0f2aa2>] kmem_cache_alloc_trace+0x2b4/0x3d4 [<000000005fcec025>] do_eventfd+0x54/0x1ac [<0000000082791a69>] __arm64_sys_eventfd2+0x34/0x44 [<00000000b819758c>] do_el0_svc+0x128/0x1dc [<00000000b244e810>] el0_sync_handler+0xd0/0x268 [<00000000d495ef94>] el0_sync+0x164/0x180 Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-05-18vfio-pci: Invalidate mmaps and block MMIO access on disabled memoryAlex Williamson1-33/+258
Accessing the disabled memory space of a PCI device would typically result in a master abort response on conventional PCI, or an unsupported request on PCI express. The user would generally see these as a -1 response for the read return data and the write would be silently discarded, possibly with an uncorrected, non-fatal AER error triggered on the host. Some systems however take it upon themselves to bring down the entire system when they see something that might indicate a loss of data, such as this discarded write to a disabled memory space. To avoid this, we want to try to block the user from accessing memory spaces while they're disabled. We start with a semaphore around the memory enable bit, where writers modify the memory enable state and must be serialized, while readers make use of the memory region and can access in parallel. Writers include both direct manipulation via the command register, as well as any reset path where the internal mechanics of the reset may both explicitly and implicitly disable memory access, and manipulation of the MSI-X configuration, where the MSI-X vector table resides in MMIO space of the device. Readers include the read and write file ops to access the vfio device fd offsets as well as memory mapped access. In the latter case, we make use of our new vma list support to zap, or invalidate, those memory mappings in order to force them to be faulted back in on access. Our semaphore usage will stall user access to MMIO spaces across internal operations like reset, but the user might experience new behavior when trying to access the MMIO space while disabled via the PCI command register. Access via read or write while disabled will return -EIO and access via memory maps will result in a SIGBUS. This is expected to be compatible with known use cases and potentially provides better error handling capabilities than present in the hardware, while avoiding the more readily accessible and severe platform error responses that might otherwise occur. Fixes: CVE-2020-12888 Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-05-18vfio-pci: Fault mmaps to enable vma trackingAlex Williamson1-2/+74
Rather than calling remap_pfn_range() when a region is mmap'd, setup a vm_ops handler to support dynamic faulting of the range on access. This allows us to manage a list of vmas actively mapping the area that we can later use to invalidate those mappings. The open callback invalidates the vma range so that all tracking is inserted in the fault handler and removed in the close handler. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-03-24vfio/pci: Cleanup .probe() exit pathsAlex Williamson1-29/+25
The cleanup is getting a tad long. Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-03-24vfio/pci: Remove dev_fmt definitionAlex Williamson1-1/+0
It currently results in messages like: "vfio-pci 0000:03:00.0: vfio_pci: ..." Which is quite a bit redundant. Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-03-24vfio/pci: Add sriov_configure supportAlex Williamson1-11/+95
With the VF Token interface we can now expect that a vfio userspace driver must be in collaboration with the PF driver, an unwitting userspace driver will not be able to get past the GET_DEVICE_FD step in accessing the device. We can now move on to actually allowing SR-IOV to be enabled by vfio-pci on the PF. Support for this is not enabled by default in this commit, but it does provide a module option for this to be enabled (enable_sriov=1). Enabling VFs is rather straightforward, except we don't want to risk that a VF might get autoprobed and bound to other drivers, so a bus notifier is used to "capture" VFs to vfio-pci using the driver_override support. We assume any later action to bind the device to other drivers is condoned by the system admin and allow it with a log warning. vfio-pci will disable SR-IOV on a PF before releasing the device, allowing a VF driver to be assured other drivers cannot take over the PF and that any other userspace driver must know the shared VF token. This support also does not provide a mechanism for the PF userspace driver itself to manipulate SR-IOV through the vfio API. With this patch SR-IOV can only be enabled via the host sysfs interface and the PF driver user cannot create or remove VFs. Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
generated by cgit v1.2.3 (git 2.39.0) at 2025-02-26 23:58:59 +0300