Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'vfio-v6.15-rc6' of https://github.com/awilliam/linux-vfio
Pull vfio fix from Alex Williamson:
- Fix an issue in vfio-pci huge_fault handling by aligning faults to
the order, resulting in deterministic use of huge pages. This
avoids a race where simultaneous aligned and unaligned faults to
the same PMD can result in a VM_FAULT_OOM and subsequent VM crash.
(Alex Williamson)
* tag 'vfio-v6.15-rc6' of https://github.com/awilliam/linux-vfio:
vfio/pci: Align huge faults to order
+6
-6
+6
-6
drivers/vfio/pci/vfio_pci_core.c
+6
-6
drivers/vfio/pci/vfio_pci_core.c
···
1646
1646
{
1647
1647
struct vm_area_struct *vma = vmf->vma;
1648
1648
struct vfio_pci_core_device *vdev = vma->vm_private_data;
1649
-
unsigned long pfn, pgoff = vmf->pgoff - vma->vm_pgoff;
1649
+
unsigned long addr = vmf->address & ~((PAGE_SIZE << order) - 1);
1650
+
unsigned long pgoff = (addr - vma->vm_start) >> PAGE_SHIFT;
1651
+
unsigned long pfn = vma_to_pfn(vma) + pgoff;
1650
1652
vm_fault_t ret = VM_FAULT_SIGBUS;
1651
1653
1652
-
pfn = vma_to_pfn(vma) + pgoff;
1653
-
1654
-
if (order && (pfn & ((1 << order) - 1) ||
1655
-
vmf->address & ((PAGE_SIZE << order) - 1) ||
1656
-
vmf->address + (PAGE_SIZE << order) > vma->vm_end)) {
1654
+
if (order && (addr < vma->vm_start ||
1655
+
addr + (PAGE_SIZE << order) > vma->vm_end ||
1656
+
pfn & ((1 << order) - 1))) {
1657
1657
ret = VM_FAULT_FALLBACK;
1658
1658
goto out;
1659
1659
}