Alex Williamson 48d8476b41 vfio/type1: Fix task tracking for QEMU vCPU hotplug ... MAP_DMA ioctls might be called from various threads within a process, for example when using QEMU, the vCPU threads are often generating these calls and we therefore take a reference to that vCPU task. However, QEMU also supports vCPU hotplug on some machines and the task that called MAP_DMA may have exited by the time UNMAP_DMA is called, resulting in the mm_struct pointer being NULL and thus a failure to match against the existing mapping. To resolve this, we instead take a reference to the thread group_leader, which has the same mm_struct and resource limits, but is less likely exit, at least in the QEMU case. A difficulty here is guaranteeing that the capabilities of the group_leader match that of the calling thread, which we resolve by tracking CAP_IPC_LOCK at the time of calling rather than at an indeterminate time in the future. Potentially this also results in better efficiency as this is now recorded once per MAP_DMA ioctl. Reported-by: Xu Yandong <xuyandong2@huawei.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>		2018-06-08 10:21:39 -06:00
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mdev
pci	VFIO updates for v4.17-rc1	2018-04-06 19:44:27 -07:00
platform
Kconfig
Makefile
vfio.c
vfio_iommu_spapr_tce.c
vfio_iommu_type1.c	vfio/type1: Fix task tracking for QEMU vCPU hotplug	2018-06-08 10:21:39 -06:00
vfio_spapr_eeh.c
virqfd.c