kernel.git/drivers/dma/idxd/cdev.c, branch linux-6.3.y

mm: replace vma->vm_flags direct modifications with modifier calls

2023-02-10T00:51:39Z

Replace direct modifications to vma->vm_flags with calls to modifier functions to be able to track flag changes and to keep vma locking correctness. [akpm@linux-foundation.org: fix drivers/misc/open-dice.c, per Hyeonggon Yoo] Link: https://lkml.kernel.org/r/20230126193752.297968-5-surenb@google.com Signed-off-by: Suren Baghdasaryan Acked-by: Michal Hocko Acked-by: Mel Gorman Acked-by: Mike Rapoport (IBM) Acked-by: Sebastian Reichel Reviewed-by: Liam R. Howlett Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Andy Lutomirski Cc: Arjun Roy Cc: Axel Rasmussen Cc: David Hildenbrand Cc: David Howells Cc: Davidlohr Bueso Cc: David Rientjes Cc: Eric Dumazet Cc: Greg Thelen Cc: Hugh Dickins Cc: Ingo Molnar Cc: Jann Horn Cc: Joel Fernandes Cc: Johannes Weiner Cc: Kent Overstreet Cc: Laurent Dufour Cc: Lorenzo Stoakes Cc: Matthew Wilcox Cc: Minchan Kim Cc: Paul E. McKenney Cc: Peter Oskolkov Cc: Peter Xu Cc: Peter Zijlstra Cc: Punit Agrawal Cc: Sebastian Andrzej Siewior Cc: Shakeel Butt Cc: Soheil Hassas Yeganeh Cc: Song Liu Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton

Merge tag 'v6.1-rc7' into iommufd.git for-next

2022-12-02T16:04:39Z

Resolve conflicts in drivers/vfio/vfio_main.c by using the iommfd version. The rc fix was done a different way when iommufd patches reworked this code. Signed-off-by: Jason Gunthorpe

iommu: Remove SVM_FLAG_SUPERVISOR_MODE support

2022-11-03T14:47:45Z

The current kernel DMA with PASID support is based on the SVA with a flag SVM_FLAG_SUPERVISOR_MODE. The IOMMU driver binds the kernel memory address space to a PASID of the device. The device driver programs the device with kernel virtual address (KVA) for DMA access. There have been security and functional issues with this approach: - The lack of IOTLB synchronization upon kernel page table updates. (vmalloc, module/BPF loading, CONFIG_DEBUG_PAGEALLOC etc.) - Other than slight more protection, using kernel virtual address (KVA) has little advantage over physical address. There are also no use cases yet where DMA engines need kernel virtual addresses for in-kernel DMA. This removes SVM_FLAG_SUPERVISOR_MODE support from the IOMMU interface. The device drivers are suggested to handle kernel DMA with PASID through the kernel DMA APIs. The drvdata parameter in iommu_sva_bind_device() and all callbacks is not needed anymore. Cleanup them as well. Link: https://lore.kernel.org/linux-iommu/20210511194726.GP1002214@nvidia.com/ Signed-off-by: Jacob Pan Signed-off-by: Lu Baolu Reviewed-by: Jason Gunthorpe Reviewed-by: Jean-Philippe Brucker Reviewed-by: Kevin Tian Reviewed-by: Fenghua Yu Tested-by: Zhangfei Gao Tested-by: Tony Zhu Link: https://lore.kernel.org/r/20221031005917.45690-4-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel

dmaengine: idxd: Do not enable user type Work Queue without Shared Virtual Addressing

2022-10-19T13:32:10Z

When the idxd_user_drv driver is bound to a Work Queue (WQ) device without IOMMU or with IOMMU Passthrough without Shared Virtual Addressing (SVA), the application gains direct access to physical memory via the device by programming physical address to a submitted descriptor. This allows direct userspace read and write access to arbitrary physical memory. This is inconsistent with the security goals of a good kernel API. Unlike vfio_pci driver, the IDXD char device driver does not provide any ways to pin user pages and translate the address from user VA to IOVA or PA without IOMMU SVA. Therefore the application has no way to instruct the device to perform DMA function. This makes the char device not usable for normal application usage. Since user type WQ without SVA cannot be used for normal application usage and presents the security issue, bind idxd_user_drv driver and enable user type WQ only when SVA is enabled (i.e. user PASID is enabled). Fixes: 448c3de8ac83 ("dmaengine: idxd: create user driver for wq 'device'") Cc: stable@vger.kernel.org Suggested-by: Arjan Van De Ven Signed-off-by: Fenghua Yu Reviewed-by: Dave Jiang Reviewed-by: Jerry Snitselaar Link: https://lore.kernel.org/r/20221014222541.3912195-1-fenghua.yu@intel.com Signed-off-by: Vinod Koul

dmaengine: idxd: Separate user and kernel pasid enabling

2022-05-16T12:49:29Z

The idxd driver always gated the pasid enabling under a single knob and this assumption is incorrect. The pasid used for kernel operation can be independently toggled and has no dependency on the user pasid (and vice versa). Split the two so they are independent "enabled" flags. Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/165231431746.986466.5666862038354800551.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul

dmaengine: idxd: Fix the error handling path in idxd_cdev_register()

2022-05-16T11:28:32Z

If a call to alloc_chrdev_region() fails, the already allocated resources are leaking. Add the needed error handling path to fix the leak. Fixes: 42d279f9137a ("dmaengine: idxd: add char driver to expose submission portal to userland") Signed-off-by: Christophe JAILLET Acked-by: Dave Jiang Link: https://lore.kernel.org/r/1b5033dcc87b5f2a953c413f0306e883e6114542.1650521591.git.christophe.jaillet@wanadoo.fr Signed-off-by: Vinod Koul

dmaengine: idxd: refactor wq driver enable/disable operations

2022-04-22T07:24:20Z

Move the core driver operations from wq driver to the drv_enable_wq() and drv_disable_wq() functions. The move should reduce the wq driver's knowledge of the core driver operations and prevent code confusion for future wq drivers. Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/165047301643.3841827.11222723219862233060.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul

dmaengine: idxd: remove interrupt disable for dev_lock

2021-08-29T13:44:20Z

The spinlock is not being used in hard interrupt context. There is no need to disable irq when acquiring the lock. The interrupt thread handler also is not in bottom half context, therefore we can also remove disabling of the bh. Convert all dev_lock acquisition to plain spin_lock() calls. Reviewed-by: Dan Williams Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/162984026772.1939166.11504067782824765879.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul

dmanegine: idxd: add software command status

2021-07-28T12:26:55Z

Enabling device and wq returns standard errno and that does not provide enough details to indicate what exactly failed. The hardware command status is only 8bits. Expand the command status to 32bits and use the upper 16 bits to define software errors to provide more details on the exact failure. Bit 31 will be used to indicate the error is software set as the driver is using some of the spec defined hardware error as well. Cc: Ramesh Thomas Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/162681373579.1968485.5891788397526827892.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul

dmaengine: idxd: move dsa_drv support to compatible mode

2021-07-21T04:39:16Z

The original architecture of /sys/bus/dsa invented a scheme whereby a single entry in the list of bus drivers, /sys/bus/drivers/dsa, handled all device types and internally routed them to different different drivers. Those internal drivers were invisible to userspace. With the idxd driver transitioned to a proper bus device-driver model, the legacy behavior needs to be preserved due to it being exposed to user space via sysfs. Create a compat driver to provide the legacy behavior for /sys/bus/dsa/drivers/dsa. This should satisfy user tool accel-config v3.2 or ealier where this behavior is expected. If the distro has a newer accel-config then the legacy mode does not need to be enabled. When the compat driver binds the device (i.e. dsa0) to the dsa driver, it will be bound to the new idxd_drv. The wq device (i.e. wq0.0) will be bound to either the dmaengine_drv or the user_drv. The dsa_drv becomes a routing mechansim for the new drivers. It will not support additional external drivers that are implemented later. Reviewed-by: Dan Williams Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/162637468705.744545.4399080971745974435.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul