diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2020-05-29 05:42:55 -0400 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-06-01 04:26:05 -0400 |
| commit | a8387d0b471f7c8d4d936af0d6dc44dff5c41c6c (patch) | |
| tree | 32c5927976e9b8a29ea2337d81a27cfbf3cf2a17 /virt | |
| parent | cc440cdad5b7a4c1de12dace725209eb3e0cf663 (diff) | |
| download | lwn-a8387d0b471f7c8d4d936af0d6dc44dff5c41c6c.tar.gz lwn-a8387d0b471f7c8d4d936af0d6dc44dff5c41c6c.zip | |
Revert "KVM: No need to retry for hva_to_pfn_remapped()"
This reverts commit 5b494aea13fe9ec67365510c0d75835428cbb303.
If unlocked==true then the vma pointer could be invalidated, so the 2nd
follow_pfn() is potentially racy: we do need to get out and redo
find_vma_intersection().
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/kvm_main.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index da6da386b591..c9c6db5f77c2 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1831,6 +1831,8 @@ static int hva_to_pfn_remapped(struct vm_area_struct *vma, r = fixup_user_fault(current, current->mm, addr, (write_fault ? FAULT_FLAG_WRITE : 0), &unlocked); + if (unlocked) + return -EAGAIN; if (r) return r; @@ -1901,12 +1903,15 @@ static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async, goto exit; } +retry: vma = find_vma_intersection(current->mm, addr, addr + 1); if (vma == NULL) pfn = KVM_PFN_ERR_FAULT; else if (vma->vm_flags & (VM_IO | VM_PFNMAP)) { r = hva_to_pfn_remapped(vma, addr, async, write_fault, writable, &pfn); + if (r == -EAGAIN) + goto retry; if (r < 0) pfn = KVM_PFN_ERR_FAULT; } else { |