On 1/21/26 14:47, Jason Gunthorpe wrote: > On Wed, Jan 21, 2026 at 02:59:16PM +0200, Leon Romanovsky wrote: >> From: Leon Romanovsky <[email protected]> >> >> Use the new dma_buf_attach_revocable() helper to restrict attachments to >> importers that support mapping invalidation. >> >> Signed-off-by: Leon Romanovsky <[email protected]> >> --- >> drivers/vfio/pci/vfio_pci_dmabuf.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/vfio/pci/vfio_pci_dmabuf.c >> b/drivers/vfio/pci/vfio_pci_dmabuf.c >> index 5fceefc40e27..85056a5a3faf 100644 >> --- a/drivers/vfio/pci/vfio_pci_dmabuf.c >> +++ b/drivers/vfio/pci/vfio_pci_dmabuf.c >> @@ -31,6 +31,9 @@ static int vfio_pci_dma_buf_attach(struct dma_buf *dmabuf, >> if (priv->revoked) >> return -ENODEV; >> >> + if (!dma_buf_attach_revocable(attachment)) >> + return -EOPNOTSUPP; >> + >> return 0; >> } > > We need to push an urgent -rc fix to implement a pin function here > that always fails. That was missed and it means things like rdma can > import vfio when the intention was to block that. It would be bad for > that uAPI mistake to reach a released kernel. > > It's tricky that NULL pin ops means "I support pin" :|
Well it means: "I have no memory management and my buffers are always pinned.". Christian. > > Jason
