From 338b4e10f939a71194d8ecef7ece205a942cec05 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Mon, 23 Dec 2019 12:09:27 +1100 Subject: vfio/spapr/nvlink2: Skip unpinning pages on error exit The nvlink2 subdriver for IBM Witherspoon machines preregisters GPU memory in the IOMMI API so KVM TCE code can map this memory for DMA as well. This is done by mm_iommu_newdev() called from vfio_pci_nvgpu_regops::mmap. In an unlikely event of failure the data->mem remains NULL and since mm_iommu_put() (which unregisters the region and unpins memory if that was regular memory) does not expect mem=NULL, it should not be called. This adds a check to only call mm_iommu_put() for a valid data->mem. Fixes: 7f92891778df ("vfio_pci: Add NVIDIA GV100GL [Tesla V100 SXM2] subdriver") Signed-off-by: Alexey Kardashevskiy Signed-off-by: Alex Williamson --- drivers/vfio/pci/vfio_pci_nvlink2.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'drivers/vfio/pci') diff --git a/drivers/vfio/pci/vfio_pci_nvlink2.c b/drivers/vfio/pci/vfio_pci_nvlink2.c index f2983f0f84be..3f5f8198a6bb 100644 --- a/drivers/vfio/pci/vfio_pci_nvlink2.c +++ b/drivers/vfio/pci/vfio_pci_nvlink2.c @@ -97,8 +97,10 @@ static void vfio_pci_nvgpu_release(struct vfio_pci_device *vdev, /* If there were any mappings at all... */ if (data->mm) { - ret = mm_iommu_put(data->mm, data->mem); - WARN_ON(ret); + if (data->mem) { + ret = mm_iommu_put(data->mm, data->mem); + WARN_ON(ret); + } mmdrop(data->mm); } -- cgit v1.2.3-58-ga151 From bb3d3cf928d4cc450aa817a9c71f4324ec68fd63 Mon Sep 17 00:00:00 2001 From: Julia Lawall Date: Sun, 29 Dec 2019 16:42:56 +0100 Subject: vfio: vfio_pci_nvlink2: use mmgrab Mmgrab was introduced in commit f1f1007644ff ("mm: add new mmgrab() helper") and most of the kernel was updated to use it. Update a remaining file. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) @@ expression e; @@ - atomic_inc(&e->mm_count); + mmgrab(e); Signed-off-by: Julia Lawall Reviewed-by: Cornelia Huck Signed-off-by: Alex Williamson --- drivers/vfio/pci/vfio_pci_nvlink2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/vfio/pci') diff --git a/drivers/vfio/pci/vfio_pci_nvlink2.c b/drivers/vfio/pci/vfio_pci_nvlink2.c index 3f5f8198a6bb..df4d96038cd4 100644 --- a/drivers/vfio/pci/vfio_pci_nvlink2.c +++ b/drivers/vfio/pci/vfio_pci_nvlink2.c @@ -161,7 +161,7 @@ static int vfio_pci_nvgpu_mmap(struct vfio_pci_device *vdev, data->useraddr = vma->vm_start; data->mm = current->mm; - atomic_inc(&data->mm->mm_count); + mmgrab(data->mm); ret = (int) mm_iommu_newdev(data->mm, data->useraddr, vma_pages(vma), data->gpu_hpa, &data->mem); -- cgit v1.2.3-58-ga151