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Miller" , Eric Dumazet , "=?UTF-8?q?Eugenio=20P=C3=A9rez?=" , Jakub Kicinski , Jason Wang , kvm@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, "Michael S. Tsirkin" , Paolo Abeni , Simon Horman , Stefan Hajnoczi , Stefano Garzarella , virtualization@lists.linux.dev, Xuan Zhuo , Jens Axboe , Octavian Purdila Content-Type: text/plain; charset="UTF-8" This series fixes a msg_iter desync issue in the virtio vsock transport that can lead to warnings and eventual -ENOMEM under specific failure scenarios (e.g. partial GUP failure during MSG_ZEROCOPY transmission). To fix this, we need to restore the msg_iter state on transmission failure. However, since virtio vsock transport can be built as a module, we first need to export iov_iter_restore. Patch 1 exports iov_iter_restore. Patch 2 implements the msg_iter restoration in virtio vsock. Changes in v3: - Use EXPORT_SYMBOL_GPL (Jens) Changes in v2: - Use iov_iter_savestate()/iov_iter_restore() (Stefano) - Use a single restore point (Stefano) - Reverse xmas tree (Stefano) - Added comments in the code (Stefano) v2: https://lore.kernel.org/all/20260613000953.467473-1-tavip@google.com/ v1: https://lore.kernel.org/all/20260609004809.1285028-1-tavip@google.com/ Octavian Purdila (2): iov_iter: export iov_iter_restore vsock/virtio: restore msg_iter on transmission failure lib/iov_iter.c | 1 + net/vmw_vsock/virtio_transport_common.c | 13 +++++++++++++ 2 files changed, 14 insertions(+) -- 2.55.0.rc0.799.gd6f94ed593-goog