kernel/git/stable/linux.git/drivers/vfio, branch linux-4.10.y

vfio/type1: Remove locked page accounting workqueue

2017-05-20T12:30:59+00:00

commit 0cfef2b7410b64d7a430947e0b533314c4f97153 upstream. If the mmap_sem is contented then the vfio type1 IOMMU backend will defer locked page accounting updates to a workqueue task. This has a few problems and depending on which side the user tries to play, they might be over-penalized for unmaps that haven't yet been accounted or race the workqueue to enter more mappings than they're allowed. The original intent of this workqueue mechanism seems to be focused on reducing latency through the ioctl, but we cannot do so at the cost of correctness. Remove this workqueue mechanism and update the callers to allow for failure. We can also now recheck the limit under write lock to make sure we don't exceed it. vfio_pin_pages_remote() also now necessarily includes an unwind path which we can jump to directly if the consecutive page pinning finds that we're exceeding the user's memory limits. This avoids the current lazy approach which does accounting and mapping up to the fault, only to return an error on the next iteration to unwind the entire vfio_dma. Reviewed-by: Peter Xu Reviewed-by: Kirti Wankhede Signed-off-by: Alex Williamson Signed-off-by: Greg Kroah-Hartman

vfio: Rework group release notifier warning

2017-03-30T07:44:08+00:00

commit 65b1adebfe43c642dfe3b109edb5d992db5fbe72 upstream. The intent of the original warning is make sure that the mdev vendor driver has removed any group notifiers at the point where the group is closed by the user. Theoretically this would be through an orderly shutdown where any devices are release prior to the group release. We can't always count on an orderly shutdown, the user can close the group before the notifier can be removed or the user task might be killed. We'd like to add this sanity test when the group is idle and the only references are from the devices within the group themselves, but we don't have a good way to do that. Instead check both when the group itself is removed and when the group is opened. A bit later than we'd prefer, but better than the current over aggressive approach. Fixes: ccd46dbae77d ("vfio: support notifier chain in vfio_group") Signed-off-by: Alex Williamson Cc: Jike Song Signed-off-by: Greg Kroah-Hartman

vfio/spapr_tce: Set window when adding additional groups to container

2017-02-07T18:48:16+00:00

If a container already has a group attached, attaching a new group should just program already created IOMMU tables to the hardware via the iommu_table_group_ops::set_window() callback. However commit 6f01cc692a16 ("vfio/spapr: Add a helper to create default DMA window") did not just simplify the code but also removed the set_window() calls in the case of attaching groups to a container which already has tables so it broke VFIO PCI hotplug. This reverts set_window() bits in tce_iommu_take_ownership_ddw(). Fixes: 6f01cc692a16 ("vfio/spapr: Add a helper to create default DMA window") Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson Signed-off-by: Alex Williamson

vfio/spapr: Fix missing mutex unlock when creating a window

2017-02-01T16:48:34+00:00

Commit d9c728949ddc ("vfio/spapr: Postpone default window creation") added an additional exit to the VFIO_IOMMU_SPAPR_TCE_CREATE case and made it possible to return from tce_iommu_ioctl() without unlocking container->lock; this fixes the issue. Fixes: d9c728949ddc ("vfio/spapr: Postpone default window creation") Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson Signed-off-by: Alex Williamson

vfio/spapr: fail tce_iommu_attach_group() when iommu_data is null

2017-01-24T17:12:04+00:00

The recently added mediated VFIO driver doesn't know about powerpc iommu. It thus doesn't register a struct iommu_table_group in the iommu group upon device creation. The iommu_data pointer hence remains null. This causes a kernel oops when userspace tries to set the iommu type of a container associated with a mediated device to VFIO_SPAPR_TCE_v2_IOMMU. [ 82.585440] mtty mtty: MDEV: Registered [ 87.655522] iommu: Adding device 83b8f4f2-509f-382f-3c1e-e6bfe0fa1001 to group 10 [ 87.655527] vfio_mdev 83b8f4f2-509f-382f-3c1e-e6bfe0fa1001: MDEV: group_id = 10 [ 116.297184] Unable to handle kernel paging request for data at address 0x00000030 [ 116.297389] Faulting instruction address: 0xd000000007870524 [ 116.297465] Oops: Kernel access of bad area, sig: 11 [#1] [ 116.297611] SMP NR_CPUS=2048 [ 116.297611] NUMA [ 116.297627] PowerNV ... [ 116.297954] CPU: 33 PID: 7067 Comm: qemu-system-ppc Not tainted 4.10.0-rc5-mdev-test #8 [ 116.297993] task: c000000e7718b680 task.stack: c000000e77214000 [ 116.298025] NIP: d000000007870524 LR: d000000007870518 CTR: 0000000000000000 [ 116.298064] REGS: c000000e77217990 TRAP: 0300 Not tainted (4.10.0-rc5-mdev-test) [ 116.298103] MSR: 9000000000009033 [ 116.298107] CR: 84004444 XER: 00000000 [ 116.298154] CFAR: c00000000000888c DAR: 0000000000000030 DSISR: 40000000 SOFTE: 1 GPR00: d000000007870518 c000000e77217c10 d00000000787b0ed c000000eed2103c0 GPR04: 0000000000000000 0000000000000000 c000000eed2103e0 0000000f24320000 GPR08: 0000000000000104 0000000000000001 0000000000000000 d0000000078729b0 GPR12: c00000000025b7e0 c00000000fe08400 0000000000000001 000001002d31d100 GPR16: 000001002c22c850 00003ffff315c750 0000000043145680 0000000043141bc0 GPR20: ffffffffffffffed fffffffffffff000 0000000020003b65 d000000007706018 GPR24: c000000f16cf0d98 d000000007706000 c000000003f42980 c000000003f42980 GPR28: c000000f1575ac00 c000000003f429c8 0000000000000000 c000000eed2103c0 [ 116.298504] NIP [d000000007870524] tce_iommu_attach_group+0x10c/0x360 [vfio_iommu_spapr_tce] [ 116.298555] LR [d000000007870518] tce_iommu_attach_group+0x100/0x360 [vfio_iommu_spapr_tce] [ 116.298601] Call Trace: [ 116.298610] [c000000e77217c10] [d000000007870518] tce_iommu_attach_group+0x100/0x360 [vfio_iommu_spapr_tce] (unreliable) [ 116.298671] [c000000e77217cb0] [d0000000077033a0] vfio_fops_unl_ioctl+0x278/0x3e0 [vfio] [ 116.298713] [c000000e77217d40] [c0000000002a3ebc] do_vfs_ioctl+0xcc/0x8b0 [ 116.298745] [c000000e77217de0] [c0000000002a4700] SyS_ioctl+0x60/0xc0 [ 116.298782] [c000000e77217e30] [c00000000000b220] system_call+0x38/0xfc [ 116.298812] Instruction dump: [ 116.298828] 7d3f4b78 409effc8 3d220000 e9298020 3c800140 38a00018 608480c0 e8690028 [ 116.298869] 4800249d e8410018 7c7f1b79 41820230 2fa90000 419e0114 e9090020 [ 116.298914] ---[ end trace 1e10b0ced08b9120 ]--- This patch fixes the oops. Reported-by: Vaibhav Jain Signed-off-by: Greg Kurz Signed-off-by: Alex Williamson

vfio/type1: Remove pid_namespace.h include

2017-01-13T15:23:33+00:00

Using has_capability() rather than ns_capable(), we're no longer using this header. Cc: Jike Song Cc: Kirti Wankhede Signed-off-by: Alex Williamson

vfio iommu type1: fix the testing of capability for remote task

2017-01-12T23:05:35+00:00

Before the mdev enhancement type1 iommu used capable() to test the capability of current task; in the course of mdev development a new requirement, testing for another task other than current, was raised. ns_capable() was used for this purpose, however it still tests current, the only difference is, in a specified namespace. Fix it by using has_capability() instead, which tests the cap for specified task in init_user_ns, the same namespace as capable(). Cc: Gerd Hoffmann Signed-off-by: Jike Song Reviewed-by: James Morris Reviewed-by: Kirti Wankhede Signed-off-by: Alex Williamson

vfio-pci: Handle error from pci_iomap

2017-01-04T15:34:39+00:00

Here, pci_iomap can fail, handle this case release selected pci regions and return -ENOMEM. Signed-off-by: Arvind Yadav Signed-off-by: Alex Williamson

vfio-pci: use 32-bit comparisons for register address for gcc-4.5

2016-12-30T15:13:47+00:00

Using ancient compilers (gcc-4.5 or older) on ARM, we get a link failure with the vfio-pci driver: ERROR: "__aeabi_lcmp" [drivers/vfio/pci/vfio-pci.ko] undefined! The reason is that the compiler tries to do a comparison of a 64-bit range. This changes it to convert to a 32-bit number explicitly first, as newer compilers do for themselves. Signed-off-by: Arnd Bergmann Signed-off-by: Alex Williamson

vfio-mdev: Make mdev_device private and abstract interfaces

2016-12-30T15:13:44+00:00

Abstract access to mdev_device so that we can define which interfaces are public rather than relying on comments in the structure. Cc: Zhenyu Wang Cc: Zhi Wang Signed-off-by: Alex Williamson Reviewed-by: Jike Song Reviewed by: Kirti Wankhede