kernel.git/drivers/vfio/pci, branch linux-5.9.y

vfio/pci: Bypass IGD init in case of -ENODEV

2020-11-18T18:22:13Z

[ Upstream commit e4eccb853664de7bcf9518fb658f35e748bf1f68 ] 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 Cc: Xiong Zhang Cc: Hang Yuan Cc: Stuart Summers Signed-off-by: Fred Gao Signed-off-by: Alex Williamson Signed-off-by: Sasha Levin

vfio/pci: Implement ioeventfd thread handler for contended memory lock

2020-11-18T18:22:04Z

[ Upstream commit 38565c93c8a1306dc5f245572a545fbea908ac41 ] 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 Tested-by: Ian Pilcher Tested-by: Justin Gatzen Signed-off-by: Alex Williamson Signed-off-by: Sasha Levin

vfio/pci: Clear token on bypass registration failure

2020-10-29T09:11:57Z

[ Upstream commit 852b1beecb6ff9326f7ca4bc0fe69ae860ebdb9e ] 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 Tested-by: guomin chen Signed-off-by: Alex Williamson Signed-off-by: Sasha Levin

vfio/pci: Decouple PCI_COMMAND_MEMORY bit checks from is_virtfn

2020-10-29T09:11:54Z

[ Upstream commit 515ecd5368f1510152fa4f9b9ce55b66ac56c334 ] 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 Reviewed-by: Niklas Schnelle Reviewed-by: Pierre Morel Signed-off-by: Alex Williamson Signed-off-by: Sasha Levin

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59Z

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

vfio-pci: Avoid recursive read-lock usage

2020-08-17T17:08:18Z

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 Tested-by: Zhiyi Guo Reviewed-by: Cornelia Huck Signed-off-by: Alex Williamson

vfio/pci: Add QAT devices to denylist

2020-07-27T19:43:40Z

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 Reviewed-by: Fiona Trahe Reviewed-by: Andy Shevchenko Signed-off-by: Alex Williamson

vfio/pci: Add device denylist

2020-07-27T19:43:40Z

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 Reviewed-by: Cornelia Huck Reviewed-by: Fiona Trahe Reviewed-by: Andy Shevchenko Signed-off-by: Alex Williamson

vfio/pci: Hold igate across releasing eventfd contexts

2020-07-27T19:43:38Z

No need to release and immediately re-acquire igate while clearing out the eventfd ctxs. Reviewed-by: Cornelia Huck Signed-off-by: Alex Williamson

vfio/pci: Add Intel X550 to hidden INTx devices

2020-07-27T19:43:37Z

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 Signed-off-by: Alex Williamson