kernel/linux.git/drivers/net/ethernet/google, branch v7.1.8

gve: fix Rx queue stall on alloc failure

2026-08-03T09:25:59+00:00

commit b65352a1bac64442ad95e64f385b40ccb9f1b0db upstream. When the system is under extreme memory pressure, page allocations can fail during the Rx buffer refill loop. If the number of buffers posted to hardware falls below a critical low threshold and the refill loop exits due to allocation failures, the queue can stall: 1. The device drops incoming packets because there are no descriptors. 2. Since no packets are processed, no Rx completions are generated. 3. Because no completions occur, NAPI is never scheduled, preventing the refill loop from running again even after memory is freed. This results in a permanent queue stall. Resolve this by introducing a starvation recovery timer for each Rx queue. If the number of buffers posted to hardware falls below a critical low threshold, start a timer to periodically reschedule NAPI. Once NAPI runs and successfully refills the queue above the threshold, the timer is not rescheduled. The threshold is set to 32 because a single maximum-sized Receive Segment Coalescing (RSC) packet can consume up to 19 descriptors in the Rx path. Lower thresholds (such as 8 or 16) would be insufficient to process a complete maximum-sized RSC packet, risking packet drops or unexpected hardware behavior under memory pressure. Setting the threshold to 32 guarantees a safe margin to handle at least one full RSC packet. Cc: stable@vger.kernel.org Fixes: 9b8dd5e5ea48 ("gve: DQO: Add RX path") Reviewed-by: Jordan Rhee Signed-off-by: Eddie Phillips Signed-off-by: Harshitha Ramamurthy Reviewed-by: Przemek Kitszel Link: https://patch.msgid.link/20260709211906.3322883-1-hramamurthy@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

gve: fix header buffer corruption with header-split and HW-GRO

2026-07-24T14:21:16+00:00

commit d676c9a73bdcd8237425dbb826f2bd1a25c36e40 upstream. The DQO RX datapath programs a per-buffer-queue-descriptor header_buf_addr at post time and reads the split header back at completion time. Both the post and the read currently index the header buffer by queue position rather than by the buffer's identity: - post (gve_rx_post_buffers_dqo): header_buf_addr is computed from bufq->tail - read (gve_rx_dqo): the header is read from desc_idx (the completion queue head index) This relies on the buffer-queue index and the completion-queue index being equal for the start of every packet, i.e. on the device consuming posted buffers and returning completions in the exact same order. That assumption does not hold once HW-GRO is enabled with multiple flows: coalesced segments are accepted and completed in an order that may differ from the order buffers were posted, and segments from different flows may interleave. That results in two problems: 1. Wrong header slot on read. Because the read offset is derived from the completion index (desc_idx) while the device wrote the header to the address programmed for the buffer's buf_id, the driver can copy a header belonging to a different packet. This shows up as throughput drop (about 30% drop and large numbers of TCP retransmissions) with header-split and HW-GRO both enabled and many streams. 2. Header buffer reused while still owned by the device. The driver advances bufq->head by one per completion and re-posts buffers based on that. Arrival of N RX completions only guarantees that at least N RX buffer descriptors have been read by the device. It does not guarantee that the device has relinquished the ownership of all the buffers corresponding to those N descriptors. With out-of-order completions (e.g. the completion for a packet copied into buffer N arrives before the completion for a packet copied into buffer N-1), the driver can re-post and overwrite a header buffer that the device is still going to write into, corrupting the header of a packet whose completion has not yet been processed. Fix both issues by indexing the header buffer by buf_id on both the post and read paths. Reading from buf_id's slot is therefore always correct regardless of completion ordering (fixes problem 1). Indexing by buf_id also ties each header slot to the lifetime of its buffer state. A buffer state is only returned to the free/recycle lists when its own completion (buf_id) is processed, so its header slot can only be re-posted after the device is done with it. This makes header slot reuse safe under out-of-order completions (fixes problem 2). Allocate (gve_rx_alloc_hdr_bufs) and free (gve_rx_free_hdr_bufs) the header buffers based on num_buf_states to match the buf_id indexing. Cc: stable@vger.kernel.org Fixes: 5e37d8254e7f ("gve: Add header split data path") Signed-off-by: Ankit Garg Reviewed-by: Praveen Kaligineedi Reviewed-by: Jordan Rhee Reviewed-by: Harshitha Ramamurthy Signed-off-by: Joshua Washington Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/20260617013208.3781453-1-joshwash@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

gve: add support for UDP GSO for DQO format

2026-03-10T02:17:52+00:00

Enable support for UDP GSO when using DQO format. Advertise the feature flag during device initialization and enable offload by default. Signed-off-by: Ankit Garg Reviewed-by: Willem de Bruijn Signed-off-by: Harshitha Ramamurthy Link: https://patch.msgid.link/20260306224816.3391551-1-hramamurthy@google.com Signed-off-by: Jakub Kicinski

gve: Enable hw-gro by default if device supported

2026-03-05T14:49:51+00:00

Change the driver's default behavior to enable hw-gro whenever supported for device. Performance observations: - We observed ~10% improvement in RX single stream throughput across various MTU sizes. - No change in TCP_RR/TCP_CRR latencies Signed-off-by: Ankit Garg Reviewed-by: Willem de Bruijn Reviewed-by: Harshitha Ramamurthy Signed-off-by: Joshua Washington Link: https://patch.msgid.link/20260303195549.2679070-5-joshwash@google.com Signed-off-by: Paolo Abeni

gve: pull network headers into skb linear part

2026-03-05T14:49:51+00:00

Currently, in DQO mode with hw-gro enabled, entire received packet is placed into skb fragments when header-split is disabled. This leaves the skb linear part empty, forcing the networking stack to do multiple small memory copies to access eth, IP and TCP headers. This patch adds a single memcpy to put all headers into linear portion before packet reaches the SW GRO stack; thus eliminating multiple smaller memcpy calls. Additionally, the criteria for calling napi_gro_frags() was updated. Since skb->head is now populated, we instead check if the SKB is the cached NAPI scratchpad to ensure we continue using the zero-allocation path. Signed-off-by: Ankit Garg Reviewed-by: Eric Dumazet Reviewed-by: Harshitha Ramamurthy Signed-off-by: Joshua Washington Link: https://patch.msgid.link/20260303195549.2679070-4-joshwash@google.com Signed-off-by: Paolo Abeni

gve: fix SW coalescing when hw-GRO is used

2026-03-05T14:49:51+00:00

Leaving gso_segs unpopulated on hardware GRO packet prevents further coalescing by software stack because the kernel's GRO logic marks the SKB for flush because the expected length of all segments doesn't match actual payload length. Setting gso_segs correctly results in significantly more segments being coalesced as measured by the result of dev_gro_receive(). gso_segs are derived from payload length. When header-split is enabled, payload is in the non-linear portion of skb. And when header-split is disabled, we have to parse the headers to determine payload length. Signed-off-by: Ankit Garg Reviewed-by: Eric Dumazet Reviewed-by: Jordan Rhee Reviewed-by: Harshitha Ramamurthy Signed-off-by: Joshua Washington Link: https://patch.msgid.link/20260303195549.2679070-3-joshwash@google.com Signed-off-by: Paolo Abeni

gve: Advertise NETIF_F_GRO_HW instead of NETIF_F_LRO

2026-03-05T14:49:51+00:00

The device behind DQO format has always coalesced packets per stricter hardware GRO spec even though it was being advertised as LRO. Update advertised capability to match device behavior. Signed-off-by: Ankit Garg Reviewed-by: Willem de Bruijn Reviewed-by: Harshitha Ramamurthy Signed-off-by: Joshua Washington Link: https://patch.msgid.link/20260303195549.2679070-2-joshwash@google.com Signed-off-by: Paolo Abeni

gve: Enable reading max ring size from the device in DQO-QPL mode

2026-02-28T16:58:29+00:00

The gVNIC device indicates a device option (MODIFY_RING) to the driver, which presents a range of ring sizes from which the user is allowed to select. But in DQO-QPL queue format, the driver ignores the "max" of this range and instead allows the user to configure the ring size in the range [min, default]. This was done because increasing the ring size could result in the number of registered pages being higher than the max allowed by the device. In order to support large ring sizes, stop ignoring the "max" of the range presented in the MODIFY_RING option. Signed-off-by: Matt Olson Signed-off-by: Max Yuan Reviewed-by: Jordan Rhee Reviewed-by: Harshitha Ramamurthy Reviewed-by: Praveen Kaligineedi Signed-off-by: Joshua Washington Link: https://patch.msgid.link/20260225182342.1049816-3-joshwash@google.com Signed-off-by: Jakub Kicinski

gve: Update QPL page registration logic

2026-02-28T16:58:29+00:00

For DQO, change QPL page registration logic to be more flexible to honor the "max_registered_pages" parameter from the gVNIC device. Previously the number of RX pages per QPL was hardcoded to twice the ring size, and the number of TX pages per QPL was dictated by the device in the DQO-QPL device option. Now [in DQO-QPL mode], the driver will ignore the "tx_pages_per_qpl" parameter indicated in the DQO-QPL device option and instead allocate up to (tx_queue_length / 2) pages per TX QPL and up to (rx_queue_length * 2) pages per RX QPL while keeping the total number of pages under the "max_registered_pages". Merge DQO and GQI QPL page calculation logic into a unified gve_update_num_qpl_pages function. Add rx_pages_per_qpl to the priv struct for consumption by both DQO and GQI. Signed-off-by: Matt Olson Signed-off-by: Max Yuan Reviewed-by: Jordan Rhee Reviewed-by: Harshitha Ramamurthy Reviewed-by: Willem de Bruijn Reviewed-by: Praveen Kaligineedi Signed-off-by: Joshua Washington Link: https://patch.msgid.link/20260225182342.1049816-2-joshwash@google.com Signed-off-by: Jakub Kicinski

Merge tag 'net-7.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2026-02-26T16:00:13+00:00

Pull networking fixes from Paolo Abeni: "Including fixes from IPsec, Bluetooth and netfilter Current release - regressions: - wifi: fix dev_alloc_name() return value check - rds: fix recursive lock in rds_tcp_conn_slots_available Current release - new code bugs: - vsock: lock down child_ns_mode as write-once Previous releases - regressions: - core: - do not pass flow_id to set_rps_cpu() - consume xmit errors of GSO frames - netconsole: avoid OOB reads, msg is not nul-terminated - netfilter: h323: fix OOB read in decode_choice() - tcp: re-enable acceptance of FIN packets when RWIN is 0 - udplite: fix null-ptr-deref in __udp_enqueue_schedule_skb(). - wifi: brcmfmac: fix potential kernel oops when probe fails - phy: register phy led_triggers during probe to avoid AB-BA deadlock - eth: - bnxt_en: fix deleting of Ntuple filters - wan: farsync: fix use-after-free bugs caused by unfinished tasklets - xscale: check for PTP support properly Previous releases - always broken: - tcp: fix potential race in tcp_v6_syn_recv_sock() - kcm: fix zero-frag skb in frag_list on partial sendmsg error - xfrm: - fix race condition in espintcp_close() - always flush state and policy upon NETDEV_UNREGISTER event - bluetooth: - purge error queues in socket destructors - fix response to L2CAP_ECRED_CONN_REQ - eth: - mlx5: - fix circular locking dependency in dump - fix "scheduling while atomic" in IPsec MAC address query - gve: fix incorrect buffer cleanup for QPL - team: avoid NETDEV_CHANGEMTU event when unregistering slave - usb: validate USB endpoints" * tag 'net-7.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (72 commits) netfilter: nf_conntrack_h323: fix OOB read in decode_choice() dpaa2-switch: validate num_ifs to prevent out-of-bounds write net: consume xmit errors of GSO frames vsock: document write-once behavior of the child_ns_mode sysctl vsock: lock down child_ns_mode as write-once selftests/vsock: change tests to respect write-once child ns mode net/mlx5e: Fix "scheduling while atomic" in IPsec MAC address query net/mlx5: Fix missing devlink lock in SRIOV enable error path net/mlx5: E-switch, Clear legacy flag when moving to switchdev net/mlx5: LAG, disable MPESW in lag_disable_change() net/mlx5: DR, Fix circular locking dependency in dump selftests: team: Add a reference count leak test team: avoid NETDEV_CHANGEMTU event when unregistering slave net: mana: Fix double destroy_workqueue on service rescan PCI path MAINTAINERS: Update maintainer entry for QUALCOMM ETHQOS ETHERNET DRIVER dpll: zl3073x: Remove redundant cleanup in devm_dpll_init() selftests/net: packetdrill: Verify acceptance of FIN packets when RWIN is 0 tcp: re-enable acceptance of FIN packets when RWIN is 0 vsock: Use container_of() to get net namespace in sysctl handlers net: usb: kaweth: validate USB endpoints ...