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2021-05-24vfio/pci: zap_vma_ptes() needs MMURandy Dunlap1-0/+1
zap_vma_ptes() is only available when CONFIG_MMU is set/enabled. Without CONFIG_MMU, vfio_pci.o has build errors, so make VFIO_PCI depend on MMU. riscv64-linux-ld: drivers/vfio/pci/vfio_pci.o: in function `vfio_pci_mmap_open': vfio_pci.c:(.text+0x1ec): undefined reference to `zap_vma_ptes' riscv64-linux-ld: drivers/vfio/pci/vfio_pci.o: in function `.L0 ': vfio_pci.c:(.text+0x165c): undefined reference to `zap_vma_ptes' Fixes: 11c4cd07ba11 ("vfio-pci: Fault mmaps to enable vma tracking") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: kernel test robot <lkp@intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Cornelia Huck <cohuck@redhat.com> Cc: kvm@vger.kernel.org Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Eric Auger <eric.auger@redhat.com> Message-Id: <20210515190856.2130-1-rdunlap@infradead.org> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-05-24vfio/pci: Fix error return code in vfio_ecap_init()Zhen Lei1-1/+1
The error code returned from vfio_ext_cap_len() is stored in 'len', not in 'ret'. Fixes: 89e1f7d4c66d ("vfio: Add PCI device driver") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com> Message-Id: <20210515020458.6771-1-thunder.leizhen@huawei.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 Torvalds7-646/+195
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 Williamson7-532/+55
'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 Gunthorpe2-5/+6
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 Hellwig5-529/+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: fix a couple of spelling mistakesZhen Lei2-3/+3
There are several spelling mistakes, as follows: thru ==> through presense ==> presence Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Message-Id: <20210326083528.1329-4-thunder.leizhen@huawei.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06vfio/pci: Add support for opregion v2.1+Fred Gao1-0/+53
Before opregion version 2.0 VBT data is stored in opregion mailbox #4, but when VBT data exceeds 6KB size and cannot be within mailbox #4 then from opregion v2.0+, Extended VBT region, next to opregion is used to hold the VBT data, so the total size will be opregion size plus extended VBT region size. Since opregion v2.0 with physical host VBT address would not be practically available for end user and guest can not directly access host physical address, so it is not supported. Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Signed-off-by: Swee Yee Fonn <swee.yee.fonn@intel.com> Signed-off-by: Fred Gao <fred.gao@intel.com> Message-Id: <20210325170953.24549-1-fred.gao@intel.com> Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com> 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>
2021-03-29vfio/nvlink: Add missing SPAPR_TCE_IOMMU dependsJason Gunthorpe1-1/+1
Compiling the nvlink stuff relies on the SPAPR_TCE_IOMMU otherwise there are compile errors: drivers/vfio/pci/vfio_pci_nvlink2.c:101:10: error: implicit declaration of function 'mm_iommu_put' [-Werror,-Wimplicit-function-declaration] ret = mm_iommu_put(data->mm, data->mem); As PPC only defines these functions when the config is set. Previously this wasn't a problem by chance as SPAPR_TCE_IOMMU was the only IOMMU that could have satisfied IOMMU_API on POWERNV. Fixes: 179209fa1270 ("vfio: IOMMU_API should be selected") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <0-v1-83dba9768fc3+419-vfio_nvlink2_kconfig_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-02-19vfio/pci: remove CONFIG_VFIO_PCI_ZDEV from KconfigMax Gurtovoy4-21/+7
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>
2021-02-02vfio-pci/zdev: fix possible segmentation fault issueMax Gurtovoy1-0/+4
In case allocation fails, we must behave correctly and exit with error. Fixes: e6b817d4b821 ("vfio-pci/zdev: Add zPCI capabilities to VFIO_DEVICE_GET_INFO") Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-02-01vfio-pci/zdev: remove unused vdev argumentMax Gurtovoy1-12/+8
Zdev static functions do not use vdev argument. Remove it. 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>
2021-02-01vfio/pci: Fix handling of pci use accessor return codesHeiner Kallweit1-5/+5
The pci user accessors return negative errno's on error. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> [aw: drop Fixes tag, pcibios_err_to_errno() behaves correctly for -errno] Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-12-02vfio/pci/nvlink2: Do not attempt NPU2 setup on POWER8NVL NPUAlexey Kardashevskiy1-2/+5
We execute certain NPU2 setup code (such as mapping an LPID to a device in NPU2) unconditionally if an Nvlink bridge is detected. However this cannot succeed on POWER8NVL machines as the init helpers return an error other than ENODEV which means the device is there is and setup failed so vfio_pci_enable() fails and pass through is not possible. This changes the two NPU2 related init helpers to return -ENODEV if there is no "memory-region" device tree property as this is the distinction between NPU and NPU2. Tested on - POWER9 pvr=004e1201, Ubuntu 19.04 host, Ubuntu 18.04 vm, NVIDIA GV100 10de:1db1 driver 418.39 - POWER8 pvr=004c0100, RHEL 7.6 host, Ubuntu 16.10 vm, NVIDIA P100 10de:15f9 driver 396.47 Fixes: 7f92891778df ("vfio_pci: Add NVIDIA GV100GL [Tesla V100 SXM2] subdriver") Cc: stable@vger.kernel.org # 5.0 Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> 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>
2020-11-03vfio/pci: Implement ioeventfd thread handler for contended memory lockAlex Williamson1-8/+35
The ioeventfd is called under spinlock with interrupts disabled, therefore if the memory lock is contended defer code that might sleep to a thread context. Fixes: bc93b9ae0151 ("vfio-pci: Avoid recursive read-lock usage") Link: https://bugzilla.kernel.org/show_bug.cgi?id=209253#c1 Reported-by: Ian Pilcher <arequipeno@gmail.com> Tested-by: Ian Pilcher <arequipeno@gmail.com> Tested-by: Justin Gatzen <justin.gatzen@gmail.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 Torvalds7-12/+225
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 ...
2020-10-19vfio/pci: Clear token on bypass registration failureAlex Williamson1-1/+3
The eventfd context is used as our irqbypass token, therefore if an eventfd is re-used, our token is the same. The irqbypass code will return an -EBUSY in this case, but we'll still attempt to unregister the producer, where if that duplicate token still exists, results in removing the wrong object. Clear the token of failed producers so that they harmlessly fall out when unregistered. Fixes: 6d7425f109d2 ("vfio: Register/unregister irq_bypass_producer") Reported-by: guomin chen <guomin_chen@sina.com> Tested-by: guomin chen <guomin_chen@sina.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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 Williamson5-0/+205
v5.10/vfio/next
2020-10-12vfio-pci/zdev: Add zPCI capabilities to VFIO_DEVICE_GET_INFOMatthew Rosato5-0/+205
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>
2020-09-22Merge branches 'v5.10/vfio/bardirty', 'v5.10/vfio/dma_avail', ↵Alex Williamson2-11/+14
'v5.10/vfio/misc', 'v5.10/vfio/no-cmd-mem' and 'v5.10/vfio/yan_zhao_fixes' into v5.10/vfio/next
2020-09-22vfio/pci: Decouple PCI_COMMAND_MEMORY bit checks from is_virtfnMatthew Rosato1-10/+14
While it is true that devices with is_virtfn=1 will have a Memory Space Enable bit that is hard-wired to 0, this is not the only case where we see this behavior -- For example some bare-metal hypervisors lack Memory Space Enable bit emulation for devices not setting is_virtfn (s390). Fix this by instead checking for the newly-added no_command_memory bit which directly denotes the need for PCI_COMMAND_MEMORY emulation in vfio. Fixes: abafbc551fdd ("vfio-pci: Invalidate mmaps and block MMIO access on disabled memory") Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-09-21vfio/pci: Don't regenerate vconfig for all BARs if !bardirtyZenghui Yu1-0/+3
Now we regenerate vconfig for all the BARs via vfio_bar_fixup(), every time any offset of any of them are read. Though BARs aren't re-read regularly, the regeneration can be avoided if no BARs had been written since they were last read, in which case vdev->bardirty is false. Let's return immediately in vfio_bar_fixup() if bardirty is false. Suggested-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Zenghui Yu <yuzenghui@huawei.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-09-21vfio/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>
2020-08-17vfio-pci: Avoid recursive read-lock usageAlex Williamson2-24/+98
A down_read on memory_lock is held when performing read/write accesses to MMIO BAR space, including across the copy_to/from_user() callouts which may fault. If the user buffer for these copies resides in an mmap of device MMIO space, the mmap fault handler will acquire a recursive read-lock on memory_lock. Avoid this by reducing the lock granularity. Sequential accesses requiring multiple ioread/iowrite cycles are expected to be rare, therefore typical accesses should not see additional overhead. VGA MMIO accesses are expected to be non-fatal regardless of the PCI memory enable bit to allow legacy probing, this behavior remains with a comment added. ioeventfds are now included in memory access testing, with writes dropped while memory space is disabled. Fixes: abafbc551fdd ("vfio-pci: Invalidate mmaps and block MMIO access on disabled memory") Reported-by: Zhiyi Guo <zhguo@redhat.com> Tested-by: Zhiyi Guo <zhguo@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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>
2020-06-25vfio/pci: Fix SR-IOV VF handling with MMIO blockingAlex Williamson1-1/+16
SR-IOV VFs do not implement the memory enable bit of the command register, therefore this bit is not set in config space after pci_enable_device(). This leads to an unintended difference between PF and VF in hand-off state to the user. We can correct this by setting the initial value of the memory enable bit in our virtualized config space. There's really no need however to ever fault a user on a VF though as this would only indicate an error in the user's management of the enable bit, versus a PF where the same access could trigger hardware faults. Fixes: abafbc551fdd ("vfio-pci: Invalidate mmaps and block MMIO access on disabled memory") 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>
2020-06-05Merge tag 'vfio-v5.8-rc1' of git://github.com/awilliam/linux-vfioLinus Torvalds5-39/+417
Pull VFIO updates from Alex Williamson: - Block accesses to disabled MMIO space (Alex Williamson) - VFIO device migration API (Kirti Wankhede) - type1 IOMMU dirty bitmap API and implementation (Kirti Wankhede) - PCI NULL capability masking (Alex Williamson) - Memory leak fixes (Qian Cai) - Reference leak fix (Qiushi Wu) * tag 'vfio-v5.8-rc1' of git://github.com/awilliam/linux-vfio: vfio iommu: typecast corrections vfio iommu: Use shift operation for 64-bit integer division vfio/mdev: Fix reference count leak in add_mdev_supported_type vfio: Selective dirty page tracking if IOMMU backed device pins pages vfio iommu: Add migration capability to report supported features vfio iommu: Update UNMAP_DMA ioctl to get dirty bitmap before unmap vfio iommu: Implementation of ioctl for dirty pages tracking vfio iommu: Add ioctl definition for dirty pages tracking vfio iommu: Cache pgsize_bitmap in struct vfio_iommu vfio iommu: Remove atomicity of ref_count of pinned pages vfio: UAPI for migration interface for device state vfio/pci: fix memory leaks of eventfd ctx vfio/pci: fix memory leaks in alloc_perm_bits() vfio-pci: Mask cap zero vfio-pci: Invalidate mmaps and block MMIO access on disabled memory vfio-pci: Fault mmaps to enable vma tracking vfio/type1: Support faulting PFNMAP vmas
2020-05-26Merge branches 'v5.8/vfio/alex-block-mmio-v3', 'v5.8/vfio/alex-zero-cap-v2' ↵Alex Williamson5-39/+417
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: fix memory leaks in alloc_perm_bits()Qian Cai1-2/+5
vfio_pci_disable() calls vfio_config_free() but forgets to call free_perm_bits() resulting in memory leaks, unreferenced object 0xc000000c4db2dee0 (size 16): comm "qemu-kvm", pid 4305, jiffies 4295020272 (age 3463.780s) hex dump (first 16 bytes): 00 00 ff 00 ff ff ff ff ff ff ff ff ff ff 00 00 ................ backtrace: [<00000000a6a4552d>] alloc_perm_bits+0x58/0xe0 [vfio_pci] [<00000000ac990549>] vfio_config_init+0xdf0/0x11b0 [vfio_pci] init_pci_cap_msi_perm at drivers/vfio/pci/vfio_pci_config.c:1125 (inlined by) vfio_msi_cap_len at drivers/vfio/pci/vfio_pci_config.c:1180 (inlined by) vfio_cap_len at drivers/vfio/pci/vfio_pci_config.c:1241 (inlined by) vfio_cap_init at drivers/vfio/pci/vfio_pci_config.c:1468 (inlined by) vfio_config_init at drivers/vfio/pci/vfio_pci_config.c:1707 [<000000006db873a1>] vfio_pci_open+0x234/0x700 [vfio_pci] [<00000000630e1906>] vfio_group_fops_unl_ioctl+0x8e0/0xb84 [vfio] [<000000009e34c54f>] ksys_ioctl+0xd8/0x130 [<000000006577923d>] sys_ioctl+0x28/0x40 [<000000006d7b1cf2>] system_call_exception+0x114/0x1e0 [<0000000008ea7dd5>] system_call_common+0xf0/0x278 unreferenced object 0xc000000c4db2e330 (size 16): comm "qemu-kvm", pid 4305, jiffies 4295020272 (age 3463.780s) hex dump (first 16 bytes): 00 ff ff 00 ff ff ff ff ff ff ff ff ff ff 00 00 ................ backtrace: [<000000004c71914f>] alloc_perm_bits+0x44/0xe0 [vfio_pci] [<00000000ac990549>] vfio_config_init+0xdf0/0x11b0 [vfio_pci] [<000000006db873a1>] vfio_pci_open+0x234/0x700 [vfio_pci] [<00000000630e1906>] vfio_group_fops_unl_ioctl+0x8e0/0xb84 [vfio] [<000000009e34c54f>] ksys_ioctl+0xd8/0x130 [<000000006577923d>] sys_ioctl+0x28/0x40 [<000000006d7b1cf2>] system_call_exception+0x114/0x1e0 [<0000000008ea7dd5>] system_call_common+0xf0/0x278 Fixes: 89e1f7d4c66d ("vfio: Add PCI device driver") Signed-off-by: Qian Cai <cai@lca.pw> [aw: rolled in follow-up patch] Signed-off-by: Alex Williamson <alex.williamson@redhat.com>