summaryrefslogtreecommitdiff
path: root/drivers/vfio/pci/vfio_pci_intrs.c
AgeCommit message (Collapse)Author
2024-04-22vfio/pci: fix potential memory leak in vfio_intx_enable()Ye Bin
If vfio_irq_ctx_alloc() failed will lead to 'name' memory leak. Fixes: 18c198c96a81 ("vfio/pci: Create persistent INTx handler") Signed-off-by: Ye Bin <yebin10@huawei.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/r/20240415015029.3699844-1-yebin10@huawei.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-04-22vfio/pci: Pass eventfd context object through irqfdAlex Williamson
Further avoid lookup of the context object by passing it through the irqfd data field. Reviewed-by: Kevin Tian <kevin.tian@intel.com> Link: https://lore.kernel.org/r/20240401195406.3720453-3-alex.williamson@redhat.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-04-22vfio/pci: Pass eventfd context to IRQ handlerAlex Williamson
Create a link back to the vfio_pci_core_device on the eventfd context object to avoid lookups in the interrupt path. The context is known valid in the interrupt handler. Reviewed-by: Kevin Tian <kevin.tian@intel.com> Link: https://lore.kernel.org/r/20240401195406.3720453-2-alex.williamson@redhat.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-03-11vfio/pci: Create persistent INTx handlerAlex Williamson
A vulnerability exists where the eventfd for INTx signaling can be deconfigured, which unregisters the IRQ handler but still allows eventfds to be signaled with a NULL context through the SET_IRQS ioctl or through unmask irqfd if the device interrupt is pending. Ideally this could be solved with some additional locking; the igate mutex serializes the ioctl and config space accesses, and the interrupt handler is unregistered relative to the trigger, but the irqfd path runs asynchronous to those. The igate mutex cannot be acquired from the atomic context of the eventfd wake function. Disabling the irqfd relative to the eventfd registration is potentially incompatible with existing userspace. As a result, the solution implemented here moves configuration of the INTx interrupt handler to track the lifetime of the INTx context object and irq_type configuration, rather than registration of a particular trigger eventfd. Synchronization is added between the ioctl path and eventfd_signal() wrapper such that the eventfd trigger can be dynamically updated relative to in-flight interrupts or irqfd callbacks. Cc: <stable@vger.kernel.org> Fixes: 89e1f7d4c66d ("vfio: Add PCI device driver") Reported-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Link: https://lore.kernel.org/r/20240308230557.805580-5-alex.williamson@redhat.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-03-11vfio/pci: Lock external INTx masking opsAlex Williamson
Mask operations through config space changes to DisINTx may race INTx configuration changes via ioctl. Create wrappers that add locking for paths outside of the core interrupt code. In particular, irq_type is updated holding igate, therefore testing is_intx() requires holding igate. For example clearing DisINTx from config space can otherwise race changes of the interrupt configuration. This aligns interfaces which may trigger the INTx eventfd into two camps, one side serialized by igate and the other only enabled while INTx is configured. A subsequent patch introduces synchronization for the latter flows. Cc: <stable@vger.kernel.org> Fixes: 89e1f7d4c66d ("vfio: Add PCI device driver") Reported-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Link: https://lore.kernel.org/r/20240308230557.805580-3-alex.williamson@redhat.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-03-11vfio/pci: Disable auto-enable of exclusive INTx IRQAlex Williamson
Currently for devices requiring masking at the irqchip for INTx, ie. devices without DisINTx support, the IRQ is enabled in request_irq() and subsequently disabled as necessary to align with the masked status flag. This presents a window where the interrupt could fire between these events, resulting in the IRQ incrementing the disable depth twice. This would be unrecoverable for a user since the masked flag prevents nested enables through vfio. Instead, invert the logic using IRQF_NO_AUTOEN such that exclusive INTx is never auto-enabled, then unmask as required. Cc: <stable@vger.kernel.org> Fixes: 89e1f7d4c66d ("vfio: Add PCI device driver") Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Link: https://lore.kernel.org/r/20240308230557.805580-2-alex.williamson@redhat.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-11-28eventfd: simplify eventfd_signal()Christian Brauner
Ever since the eventfd type was introduced back in 2007 in commit e1ad7468c77d ("signal/timer/event: eventfd core") the eventfd_signal() function only ever passed 1 as a value for @n. There's no point in keeping that additional argument. Link: https://lore.kernel.org/r/20231122-vfs-eventfd-signal-v2-2-bd549b14ce0c@kernel.org Acked-by: Xu Yilun <yilun.xu@intel.com> Acked-by: Andrew Donnellan <ajd@linux.ibm.com> # ocxl Acked-by: Eric Farman <farman@linux.ibm.com> # s390 Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-05-23vfio/pci: Support dynamic MSI-XReinette Chatre
pci_msix_alloc_irq_at() enables an individual MSI-X interrupt to be allocated after MSI-X enabling. Use dynamic MSI-X (if supported by the device) to allocate an interrupt after MSI-X is enabled. An MSI-X interrupt is dynamically allocated at the time a valid eventfd is assigned. This is different behavior from a range provided during MSI-X enabling where interrupts are allocated for the entire range whether a valid eventfd is provided for each interrupt or not. The PCI-MSIX API requires that some number of irqs are allocated for an initial set of vectors when enabling MSI-X on the device. When dynamic MSIX allocation is not supported, the vector table, and thus the allocated irq set can only be resized by disabling and re-enabling MSI-X with a different range. In that case the irq allocation is essentially a cache for configuring vectors within the previously allocated vector range. When dynamic MSI-X allocation is supported, the API still requires some initial set of irqs to be allocated, but also supports allocating and freeing specific irq vectors both within and beyond the initially allocated range. For consistency between modes, as well as to reduce latency and improve reliability of allocations, and also simplicity, this implementation only releases irqs via pci_free_irq_vectors() when either the interrupt mode changes or the device is released. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/lkml/20230403211841.0e206b67.alex.williamson@redhat.com/ Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/956c47057ae9fd45591feaa82e9ae20929889249.1683740667.git.reinette.chatre@intel.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-05-23vfio/pci: Update stale commentReinette Chatre
In preparation for surrounding code change it is helpful to ensure that existing comments are accurate. Remove inaccurate comment about direct access and update the rest of the comment to reflect the purpose of writing the cached MSI message to the device. Suggested-by: Alex Williamson <alex.williamson@redhat.com> Link: https://lore.kernel.org/lkml/20230330164050.0069e2a5.alex.williamson@redhat.com/ Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/5b605ce7dcdab5a5dfef19cec4d73ae2fdad3ae1.1683740667.git.reinette.chatre@intel.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-05-23vfio/pci: Remove interrupt context counterReinette Chatre
struct vfio_pci_core_device::num_ctx counts how many interrupt contexts have been allocated. When all interrupt contexts are allocated simultaneously num_ctx provides the upper bound of all vectors that can be used as indices into the interrupt context array. With the upcoming support for dynamic MSI-X the number of interrupt contexts does not necessarily span the range of allocated interrupts. Consequently, num_ctx is no longer a trusted upper bound for valid indices. Stop using num_ctx to determine if a provided vector is valid. Use the existence of allocated interrupt. This changes behavior on the error path when user space provides an invalid vector range. Behavior changes from early exit without any modifications to possible modifications to valid vectors within the invalid range. This is acceptable considering that an invalid range is not a valid scenario, see link to discussion. The checks that ensure that user space provides a range of vectors that is valid for the device are untouched. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/lkml/20230316155646.07ae266f.alex.williamson@redhat.com/ Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/e27d350f02a65b8cbacd409b4321f5ce35b3186d.1683740667.git.reinette.chatre@intel.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-05-23vfio/pci: Use xarray for interrupt context storageReinette Chatre
Interrupt context is statically allocated at the time interrupts are allocated. Following allocation, the context is managed by directly accessing the elements of the array using the vector as index. The storage is released when interrupts are disabled. It is possible to dynamically allocate a single MSI-X interrupt after MSI-X is enabled. A dynamic storage for interrupt context is needed to support this. Replace the interrupt context array with an xarray (similar to what the core uses as store for MSI descriptors) that can support the dynamic expansion while maintaining the custom that uses the vector as index. With a dynamic storage it is no longer required to pre-allocate interrupt contexts at the time the interrupts are allocated. MSI and MSI-X interrupt contexts are only used when interrupts are enabled. Their allocation can thus be delayed until interrupt enabling. Only enabled interrupts will have associated interrupt contexts. Whether an interrupt has been allocated (a Linux irq number exists for it) becomes the criteria for whether an interrupt can be enabled. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/lkml/20230404122444.59e36a99.alex.williamson@redhat.com/ Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/40e235f38d427aff79ae35eda0ced42502aa0937.1683740667.git.reinette.chatre@intel.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-05-23vfio/pci: Move to single error pathReinette Chatre
Enabling and disabling of an interrupt involves several steps that can fail. Cleanup after failure is done when the error is encountered, resulting in some repetitive code. Support for dynamic contexts will introduce more steps during interrupt enabling and disabling. Transition to centralized exit path in preparation for dynamic contexts to eliminate duplicate error handling code. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/72dddae8aa710ce522a74130120733af61cffe4d.1683740667.git.reinette.chatre@intel.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-05-23vfio/pci: Prepare for dynamic interrupt context storageReinette Chatre
Interrupt context storage is statically allocated at the time interrupts are allocated. Following allocation, the interrupt context is managed by directly accessing the elements of the array using the vector as index. It is possible to allocate additional MSI-X vectors after MSI-X has been enabled. Dynamic storage of interrupt context is needed to support adding new MSI-X vectors after initial allocation. Replace direct access of array elements with pointers to the array elements. Doing so reduces impact of moving to a new data structure. Move interactions with the array to helpers to mostly contain changes needed to transition to a dynamic data structure. No functional change intended. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/eab289693c8325ede9aba99380f8b8d5143980a4.1683740667.git.reinette.chatre@intel.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-05-23vfio/pci: Remove negative check on unsigned vectorReinette Chatre
User space provides the vector as an unsigned int that is checked early for validity (vfio_set_irqs_validate_and_prepare()). A later negative check of the provided vector is not necessary. Remove the negative check and ensure the type used for the vector is consistent as an unsigned int. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/28521e1b0b091849952b0ecb8c118729fc8cdc4f.1683740667.git.reinette.chatre@intel.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-05-23vfio/pci: Consolidate irq cleanup on MSI/MSI-X disableReinette Chatre
vfio_msi_disable() releases all previously allocated state associated with each interrupt before disabling MSI/MSI-X. vfio_msi_disable() iterates twice over the interrupt state: first directly with a for loop to do virqfd cleanup, followed by another for loop within vfio_msi_set_block() that removes the interrupt handler and its associated state using vfio_msi_set_vector_signal(). Simplify interrupt cleanup by iterating over allocated interrupts once. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/837acb8cbe86a258a50da05e56a1f17c1a19abbe.1683740667.git.reinette.chatre@intel.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-01-23vfio: Use GFP_KERNEL_ACCOUNT for userspace persistent allocationsJason Gunthorpe
Use GFP_KERNEL_ACCOUNT for userspace persistent allocations. The GFP_KERNEL_ACCOUNT option lets the memory allocator know that this is untrusted allocation triggered from userspace and should be a subject of kmem accounting, and as such it is controlled by the cgroup mechanism. The way to find the relevant allocations was for example to look at the close_device function and trace back all the kfrees to their allocations. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Yishai Hadas <yishaih@nvidia.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20230108154427.32609-4-yishaih@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2022-09-01vfio/pci: Mask INTx during runtime suspendAbhishek Sahu
This patch adds INTx handling during runtime suspend/resume. All the suspend/resume related code for the user to put the device into the low power state will be added in subsequent patches. The INTx lines may be shared among devices. Whenever any INTx interrupt comes for the VFIO devices, then vfio_intx_handler() will be called for each device sharing the interrupt. Inside vfio_intx_handler(), it calls pci_check_and_mask_intx() and checks if the interrupt has been generated for the current device. Now, if the device is already in the D3cold state, then the config space can not be read. Attempt to read config space in D3cold state can cause system unresponsiveness in a few systems. To prevent this, mask INTx in runtime suspend callback, and unmask the same in runtime resume callback. If INTx has been already masked, then no handling is needed in runtime suspend/resume callbacks. 'pm_intx_masked' tracks this, and vfio_pci_intx_mask() has been updated to return true if the INTx vfio_pci_irq_ctx.masked value is changed inside this function. For the runtime suspend which is triggered for the no user of VFIO device, the 'irq_type' will be VFIO_PCI_NUM_IRQS and these callbacks won't do anything. The MSI/MSI-X are not shared so similar handling should not be needed for MSI/MSI-X. vfio_msihandler() triggers eventfd_signal() without doing any device-specific config access. When the user performs any config access or IOCTL after receiving the eventfd notification, then the device will be moved to the D0 state first before servicing any request. Another option was to check this flag 'pm_intx_masked' inside vfio_intx_handler() instead of masking the interrupts. This flag is being set inside the runtime_suspend callback but the device can be in non-D3cold state (for example, if the user has disabled D3cold explicitly by sysfs, the D3cold is not supported in the platform, etc.). Also, in D3cold supported case, the device will be in D0 till the PCI core moves the device into D3cold. In this case, there is a possibility that the device can generate an interrupt. Adding check in the IRQ handler will not clear the IRQ status and the interrupt line will still be asserted. This can cause interrupt flooding. Signed-off-by: Abhishek Sahu <abhsahu@nvidia.com> Link: https://lore.kernel.org/r/20220829114850.4341-4-abhsahu@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2022-09-01vfio/pci: Simplify the is_intx/msi/msix/etc definesJason Gunthorpe
Only three of these are actually used, simplify to three inline functions, and open code the if statement in vfio_pci_config.c. Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Link: https://lore.kernel.org/r/3-v2-1bd95d72f298+e0e-vfio_pci_priv_jgg@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2022-09-01vfio/pci: Split linux/vfio_pci_core.hJason Gunthorpe
The header in include/linux should have only the exported interface for other vfio_pci modules to use. Internal definitions for vfio_pci.ko should be in a "priv" header along side the .c files. Move the internal declarations out of vfio_pci_core.h. They either move to vfio_pci_priv.h or to the C file that is the only user. Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Link: https://lore.kernel.org/r/1-v2-1bd95d72f298+e0e-vfio_pci_priv_jgg@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-26vfio/pci: Introduce vfio_pci_core.koMax Gurtovoy
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>
2021-08-26vfio/pci: Rename vfio_pci_device to vfio_pci_core_deviceMax Gurtovoy
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. The new vfio_pci_core_device structure will be the main structure of the core driver and later on vfio_pci_device structure will be the main structure of the generic vfio_pci driver. 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/20210826103912.128972-4-yishaih@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-26vfio/pci: Rename vfio_pci_private.h to vfio_pci_core.hMax Gurtovoy
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/20210826103912.128972-3-yishaih@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-10-19vfio/pci: Clear token on bypass registration failureAlex Williamson
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>
2020-05-18vfio-pci: Invalidate mmaps and block MMIO access on disabled memoryAlex Williamson
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>
2019-12-02vfio/pci: call irq_bypass_unregister_producer() before freeing irqJiang Yi
Since irq_bypass_register_producer() is called after request_irq(), we should do tear-down in reverse order: irq_bypass_unregister_producer() then free_irq(). Specifically free_irq() may release resources required by the irqbypass del_producer() callback. Notably an example provided by Marc Zyngier on arm64 with GICv4 that he indicates has the potential to wedge the hardware: free_irq(irq) __free_irq(irq) irq_domain_deactivate_irq(irq) its_irq_domain_deactivate() [unmap the VLPI from the ITS] kvm_arch_irq_bypass_del_producer(cons, prod) kvm_vgic_v4_unset_forwarding(kvm, irq, ...) its_unmap_vlpi(irq) [Unmap the VLPI from the ITS (again), remap the original LPI] Signed-off-by: Jiang Yi <giangyi@amazon.com> Cc: stable@vger.kernel.org # v4.4+ Fixes: 6d7425f109d26 ("vfio: Register/unregister irq_bypass_producer") Link: https://lore.kernel.org/kvm/20191127164910.15888-1-giangyi@amazon.com Reviewed-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Eric Auger <eric.auger@redhat.com> [aw: commit log] Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-26vfio/pci: Fix integer overflows, bitmask checkVlad Tsyrklevich
The VFIO_DEVICE_SET_IRQS ioctl did not sufficiently sanitize user-supplied integers, potentially allowing memory corruption. This patch adds appropriate integer overflow checks, checks the range bounds for VFIO_IRQ_SET_DATA_NONE, and also verifies that only single element in the VFIO_IRQ_SET_DATA_TYPE_MASK bitmask is set. VFIO_IRQ_SET_ACTION_TYPE_MASK is already correctly checked later in vfio_pci_set_irqs_ioctl(). Furthermore, a kzalloc is changed to a kcalloc because the use of a kzalloc with an integer multiplication allowed an integer overflow condition to be reached without this patch. kcalloc checks for overflow and should prevent a similar occurrence. Signed-off-by: Vlad Tsyrklevich <vlad@tsyrklevich.net> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-09-29vfio_pci: use pci_alloc_irq_vectorsChristoph Hellwig
Simplify the interrupt setup by using the new PCI layer helpers. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-09-26vfio-pci: Disable INTx after MSI/X teardownAlex Williamson
The MSI/X shutdown path can gratuitously enable INTx, which is not something we want to happen if we're dealing with broken INTx device. Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-08-08vfio/pci: Fix NULL pointer oops in error interrupt setup handlingAlex Williamson
There are multiple cases in vfio_pci_set_ctx_trigger_single() where we assume we can safely read from our data pointer without actually checking whether the user has passed any data via the count field. VFIO_IRQ_SET_DATA_NONE in particular is entirely broken since we attempt to pull an int32_t file descriptor out before even checking the data type. The other data types assume the data pointer contains one element of their type as well. In part this is good news because we were previously restricted from doing much sanitization of parameters because it was missed in the past and we didn't want to break existing users. Clearly DATA_NONE is completely broken, so it must not have any users and we can fix it up completely. For DATA_BOOL and DATA_EVENTFD, we'll just protect ourselves, returning error when count is zero since we previously would have oopsed. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Reported-by: Chris Thompson <the_cartographer@hotmail.com> Cc: stable@vger.kernel.org Reviewed-by: Eric Auger <eric.auger@redhat.com>
2016-05-30vfio/pci: Fix ordering of eventfd vs virqfd shutdownAlex Williamson
Both the INTx and MSI/X disable paths do an eventfd_ctx_put() for the trigger eventfd before calling vfio_virqfd_disable() any potential mask and unmask eventfds. This opens a use-after-free race where an inopportune irqfd can reference the freed signalling eventfd. Reorder to avoid this possibility. Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-02-22vfio/pci: Fix unsigned comparison overflowAlex Williamson
Signed versus unsigned comparisons are implicitly cast to unsigned, which result in a couple possible overflows. For instance (start + count) might overflow and wrap, getting through our validation test. Also when unwinding setup, -1 being compared as unsigned doesn't produce the intended stop condition. Fix both of these and also fix vfio_msi_set_vector_signal() to validate parameters before using the vector index, though none of the callers should pass bad indexes anymore. Reported-by: Eric Auger <eric.auger@linaro.org> Reviewed-by: Eric Auger <eric.auger@linaro.org> Tested-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-10-01vfio: Register/unregister irq_bypass_producerFeng Wu
This patch adds the registration/unregistration of an irq_bypass_producer for MSI/MSIx on vfio pci devices. Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Feng Wu <feng.wu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-16vfio: move eventfd support code for VFIO_PCI to a separate fileAntonios Motakis
The virqfd functionality that is used by VFIO_PCI to implement interrupt masking and unmasking via an eventfd, is generic enough and can be reused by another driver. Move it to a separate file in order to allow the code to be shared. Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com> Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com> Reviewed-by: Eric Auger <eric.auger@linaro.org> Tested-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-03-16vfio: pass an opaque pointer on virqfd initializationAntonios Motakis
VFIO_PCI passes the VFIO device structure *vdev via eventfd to the handler that implements masking/unmasking of IRQs via an eventfd. We can replace it in the virqfd infrastructure with an opaque type so we can make use of the mechanism from other VFIO bus drivers. Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com> Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com> Reviewed-by: Eric Auger <eric.auger@linaro.org> Tested-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-03-16vfio: add local lock for virqfd instead of depending on VFIO PCIAntonios Motakis
The Virqfd code needs to keep accesses to any struct *virqfd safe, but this comes into play only when creating or destroying eventfds, so sharing the same spinlock with the VFIO bus driver is not necessary. Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com> Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com> Reviewed-by: Eric Auger <eric.auger@linaro.org> Tested-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-03-16vfio: virqfd: rename vfio_pci_virqfd_init and vfio_pci_virqfd_exitAntonios Motakis
The functions vfio_pci_virqfd_init and vfio_pci_virqfd_exit are not really PCI specific, since we plan to reuse the virqfd code with more VFIO drivers in addition to VFIO_PCI. Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com> [Baptiste Reynal: Move rename vfio_pci_virqfd_init and vfio_pci_virqfd_exit from "vfio: add a vfio_ prefix to virqfd_enable and virqfd_disable and export"] Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com> Reviewed-by: Eric Auger <eric.auger@linaro.org> Tested-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-03-16vfio: add a vfio_ prefix to virqfd_enable and virqfd_disable and exportAntonios Motakis
We want to reuse virqfd functionality in multiple VFIO drivers; before moving these functions to core VFIO, add the vfio_ prefix to the virqfd_enable and virqfd_disable functions, and export them so they can be used from other modules. Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com> Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com> Reviewed-by: Eric Auger <eric.auger@linaro.org> Tested-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-03-12vfio-pci: Add missing break to enable VFIO_PCI_ERR_IRQ_INDEXAlexey Kardashevskiy
This adds a missing break statement to VFIO_DEVICE_SET_IRQS handler without which vfio_pci_set_err_trigger() would never be called. While we are here, add another "break" to VFIO_PCI_REQ_IRQ_INDEX case so if we add more indexes later, we won't miss it. Fixes: 6140a8f56238 ("vfio-pci: Add device request interface") Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10vfio-pci: Add device request interfaceAlex Williamson
Userspace can opt to receive a device request notification, indicating that the device should be released. This is setup the same way as the error IRQ and also supports eventfd signaling. Future support may forcefully remove the device from the user if the request is ignored. Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10vfio-pci: Generalize setup of simple eventfdsAlex Williamson
We want another single vector IRQ index to support signaling of the device request to userspace. Generalize the error reporting IRQ index to avoid code duplication. Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-11-23PCI/MSI: Rename write_msi_msg() to pci_write_msi_msg()Jiang Liu
Rename write_msi_msg() to pci_write_msi_msg() to mark it as PCI specific. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Grant Likely <grant.likely@linaro.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Yingjoe Chen <yingjoe.chen@mediatek.com> Cc: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-09-29vfio/pci: Restore MSIx message prior to enablingGavin Shan
The MSIx vector table lives in device memory, which may be cleared as part of a backdoor device reset. This is the case on the IBM IPR HBA when the BIST is run on the device. When assigned to a QEMU guest, the guest driver does a pci_save_state(), issues a BIST, then does a pci_restore_state(). The BIST clears the MSIx vector table, but due to the way interrupts are configured the pci_restore_state() does not restore the vector table as expected. Eventually this results in an EEH error on Power platforms when the device attempts to signal an interrupt with the zero'd table entry. Fix the problem by restoring the host cached MSI message prior to enabling each vector. Reported-by: Wen Xiong <wenxiong@linux.vnet.ibm.com> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-02-14vfio: Use pci_enable_msi_range() and pci_enable_msix_range()Alexander Gordeev
pci_enable_msix() and pci_enable_msi_block() have been deprecated; use pci_enable_msix_range() and pci_enable_msi_range() instead. [bhelgaas: changelog] Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Alex Williamson <alex.williamson@redhat.com>
2014-01-14vfio-pci: Don't use device_lock around AER interrupt setupAlex Williamson
device_lock is much too prone to lockups. For instance if we have a pending .remove then device_lock is already held. If userspace attempts to modify AER signaling after that point, a deadlock occurs. eventfd setup/teardown is already protected in vfio with the igate mutex. AER is not a high performance interrupt, so we can also use the same mutex to protect signaling versus setup races. Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-08-28vfio-pci: Use fdget() rather than eventfd_fget()Alex Williamson
eventfd_fget() tests to see whether the file is an eventfd file, which we then immediately pass to eventfd_ctx_fileget(), which again tests whether the file is an eventfd file. Simplify slightly by using fdget() so that we only test that we're looking at an eventfd once. fget() could also be used, but fdget() makes use of fget_light() for another slight optimization. Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-05-02Merge tag 'vfio-for-v3.10' of git://github.com/awilliam/linux-vfioLinus Torvalds
Pull vfio updates from Alex Williamson: "Changes include extension to support PCI AER notification to userspace, byte granularity of PCI config space and access to unarchitected PCI config space, better protection around IOMMU driver accesses, default file mode fix, and a few misc cleanups." * tag 'vfio-for-v3.10' of git://github.com/awilliam/linux-vfio: vfio: Set container device mode vfio: Use down_reads to protect iommu disconnects vfio: Convert container->group_lock to rwsem PCI/VFIO: use pcie_flags_reg instead of access PCI-E Capabilities Register vfio-pci: Enable raw access to unassigned config space vfio-pci: Use byte granularity in config map vfio: make local function vfio_pci_intx_unmask_handler() static VFIO-AER: Vfio-pci driver changes for supporting AER VFIO: Wrapper for getting reference to vfio_device
2013-03-25vfio: make local function vfio_pci_intx_unmask_handler() staticWei Yongjun
vfio_pci_intx_unmask_handler() was not declared. It should be static. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-03-15vfio: include <linux/slab.h> for kmallocArnd Bergmann
The vfio drivers call kmalloc or kzalloc, but do not include <linux/slab.h>, which causes build errors on ARM. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Cc: kvm@vger.kernel.org
2013-03-11VFIO-AER: Vfio-pci driver changes for supporting AERVijay Mohan Pandarathil
- New VFIO_SET_IRQ ioctl option to pass the eventfd that is signaled when an error occurs in the vfio_pci_device - Register pci_error_handler for the vfio_pci driver - When the device encounters an error, the error handler registered by the vfio_pci driver gets invoked by the AER infrastructure - In the error handler, signal the eventfd registered for the device. - This results in the qemu eventfd handler getting invoked and appropriate action taken for the guest. Signed-off-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>