diff mbox series

[RFC,v2,7/7] Revert "virtio_ring: enable premapped mode whatever use_dma_api"

Message ID e8a8f8c3a2d67b25dd261184da6684fda1813c6d.1725616135.git.mst@redhat.com (mailing list archive)
State RFC
Headers show
Series Revert "virtio_net: rx enable premapped mode by default" | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Guessed tree name to be net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 16 this patch: 16
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 16 this patch: 16
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 16 this patch: 16
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 19 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 22 this patch: 22
netdev/source_inline success Was 0 now: 0

Commit Message

Michael S. Tsirkin Sept. 6, 2024, 9:52 a.m. UTC 
This reverts commit f9dac92ba9081062a6477ee015bd3b8c5914efc4.

leads to crashes with no ACCESS_PLATFORM when
sysctl net.core.high_order_alloc_disable=1

Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Reported-by: Si-Wei Liu <si-wei.liu@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/virtio/virtio_ring.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index be7309b1e860..06b5bdf0920e 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -2782,7 +2782,7 @@  EXPORT_SYMBOL_GPL(virtqueue_resize);
  *
  * Returns zero or a negative error.
  * 0: success.
- * -EINVAL: too late to enable premapped mode, the vq already contains buffers.
+ * -EINVAL: vring does not use the dma api, so we can not enable premapped mode.
  */
 int virtqueue_set_dma_premapped(struct virtqueue *_vq)
 {
@@ -2798,6 +2798,11 @@  int virtqueue_set_dma_premapped(struct virtqueue *_vq)
 		return -EINVAL;
 	}
 
+	if (!vq->use_dma_api) {
+		END_USE(vq);
+		return -EINVAL;
+	}
+
 	vq->premapped = true;
 	vq->do_unmap = false;