diff options
| author | Jann Horn <jannh@google.com> | 2020-10-15 20:13:00 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-16 11:11:22 -0700 |
| commit | 4d45e75a9955ade5c2f49bd96fc4173b2cec9a72 (patch) | |
| tree | 71b16b0e22ee630e2956a3285990fb49df84685e /drivers/vfio | |
| parent | 7f3bfab52cab96c510fd60dd757a32db7bc52d3c (diff) | |
mm: remove the now-unnecessary mmget_still_valid() hack
The preceding patches have ensured that core dumping properly takes the
mmap_lock. Thanks to that, we can now remove mmget_still_valid() and all
its users.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Link: http://lkml.kernel.org/r/20200827114932.3572699-8-jannh@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/vfio')
| -rw-r--r-- | drivers/vfio/pci/vfio_pci.c | 38 |
1 files changed, 18 insertions, 20 deletions
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 1ab1f5cda4ac..b0f4b92a87ed 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -1480,31 +1480,29 @@ static int vfio_pci_zap_and_vma_lock(struct vfio_pci_device *vdev, bool try) } else { mmap_read_lock(mm); } - if (mmget_still_valid(mm)) { - if (try) { - if (!mutex_trylock(&vdev->vma_lock)) { - mmap_read_unlock(mm); - mmput(mm); - return 0; - } - } else { - mutex_lock(&vdev->vma_lock); + if (try) { + if (!mutex_trylock(&vdev->vma_lock)) { + mmap_read_unlock(mm); + mmput(mm); + return 0; } - list_for_each_entry_safe(mmap_vma, tmp, - &vdev->vma_list, vma_next) { - struct vm_area_struct *vma = mmap_vma->vma; + } else { + mutex_lock(&vdev->vma_lock); + } + list_for_each_entry_safe(mmap_vma, tmp, + &vdev->vma_list, vma_next) { + struct vm_area_struct *vma = mmap_vma->vma; - if (vma->vm_mm != mm) - continue; + if (vma->vm_mm != mm) + continue; - list_del(&mmap_vma->vma_next); - kfree(mmap_vma); + list_del(&mmap_vma->vma_next); + kfree(mmap_vma); - zap_vma_ptes(vma, vma->vm_start, - vma->vm_end - vma->vm_start); - } - mutex_unlock(&vdev->vma_lock); + zap_vma_ptes(vma, vma->vm_start, + vma->vm_end - vma->vm_start); } + mutex_unlock(&vdev->vma_lock); mmap_read_unlock(mm); mmput(mm); } |