From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f197.google.com (mail-pf1-f197.google.com [209.85.210.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 85F2B4A8FE4 for ; Tue, 22 Sep 2026 19:45:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.197 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790106349; cv=none; b=cgVRSp6vcmMNDU7Zlf7suIm3APfrHZi93PZsxYAPNWv0yTCCQZkPnW3ulV+X0B+5meNBq3PABCOMLXarh5PVLDDWDqH2miI4GkDJIw36SdKsviQCynWmCj/+42qTSw95Va/09W7Zoj0l11miYQjK8dYaokVjUUVQd2M+ysFo4EU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790106349; c=relaxed/simple; bh=wRLASX/97yU9zKBfZV8vy5gzmtHXRvnvGYUyP0j3LM0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=V5BTyVZZhGuArtKXYso7vaVFdaLijPhjwLuTrdsljJ9i4U+NfWD2XsoeUiJwL/vmHO1E9oySzlgKr/xE9vnoQ/t+9zj38oPcIdOagT1xhn0oLjBiVPYoe2NVzurnr3Jhl6beXo4R7r0Y5flhnz5xescNgPIPcO4LVX/42fqe40A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--joshwash.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=ijWuoUaj; arc=none smtp.client-ip=209.85.210.197 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--joshwash.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ijWuoUaj" Received: by mail-pf1-f197.google.com with SMTP id d2e1a72fcca58-86ab8302b54so232577b3a.1 for ; Tue, 22 Sep 2026 12:45:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1790106346; x=1790711146; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:from:to:cc:subject:date:message-id:reply-to :content-type; bh=suMSGTXypfIdrYAcS87e+4uWOy37tQcyCih/ffX9UDg=; b=ijWuoUajYq5qsBoxzCYhs4T0TIDziDy9fJI7ZpKf4RQhogTx2Msw7Bc+/mdhn+C2RI GG2iEwC9gfSNuN7UHZumTIcdYOwkcL/A9mGgyKs2mA15sfvOL3rVD2LWF+58wx0ua245 3eA5b7MtiEQJM1Qckh7xJoExx0orI0lYxfTo3XlGXwBUe2NtYmoJh9yKJPKECJDItE+U J/ZpeKWn/XLsBIuhzr2RsIwEEZtWoZdxbVdVByH/qwELVi3LYYTpbK1+RkyvLLqvhof5 ZIynH45jCR2RFxyno7RHzYzQxwO6SfcxzVEgtMLQMfNEDRY8uBoc/dav/pHiSFhsZbJB qqbA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790106346; x=1790711146; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=suMSGTXypfIdrYAcS87e+4uWOy37tQcyCih/ffX9UDg=; b=YNHRORCrgWNHVVwUJJWJLg3T74z9WFomjTAVRSeD7uMslBWSTl5E04RNmRtdA9a7YO Wxs0dUpyReTwbcDZQMfUzQb2XEejWwmUncT47iqtzpdl5CjxNHeH8NJNKjXZQ49YHRBO HRq1tKLInwoCzsE5O/UKcW0kdifWOt+jepOGZHc47Sca6zpXv4Xwew3SrnnPuno/1U9E fTBaZcmPDvFk5+ijsJGB/ytdde9aDPLF7aYl9McPyVGr6jL22bBbiSya+NfWYpK9uJwR yx0gPkDLZ+xMAKmLS1uMw4MWOYuii5KrwOaqSRoSxKLkPfwPyffa5G+4Na77swl+W4fz qTZQ== X-Forwarded-Encrypted: i=1; AKwUvBw11HVhM4gUr3SNRJhL5YWpTOY6CvPRFjYQ5cUzAYj5BUMm7qHKqbmkcS9OfYELpxgs/mk=@vger.kernel.org X-Gm-Message-State: AFuF++kq2+8yIdcPjkOE4bCSGp0v44Jms8JE+ZRSVf/dE0GuJ30TYWmB NUJ/2mIAXMV3iNOZFWjpnz3QrE+0qtXEM1l6X8eJaYeiR/gm/9lC4ZwcjJHo1Bg+K1Lltr0yhsn 8s9BnoJnXzY8x2Q== X-Received: from pfko10.prod.google.com ([2002:a05:6a00:214a:b0:87d:d4a:136c]) (user=joshwash job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:3316:b0:86e:8deb:fbd4 with SMTP id d2e1a72fcca58-87d1a7af6fdmr683675b3a.11.1790106345528; Tue, 22 Sep 2026 12:45:45 -0700 (PDT) Date: Tue, 22 Sep 2026 12:45:28 -0700 In-Reply-To: <20260922194533.631387-1-joshwash@google.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260922194533.631387-1-joshwash@google.com> X-Mailer: git-send-email 2.55.0.1082.g2b9226bbc0-goog Message-ID: <20260922194533.631387-5-joshwash@google.com> Subject: [PATCH net v2 4/9] gve: don't register xsk pool on pre-existing queues in RDA mode From: Joshua Washington To: netdev@vger.kernel.org Cc: Joshua Washington , Harshitha Ramamurthy , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Stanislav Fomichev , Jordan Rhee , Willem de Bruijn , Tim Hostetler , Ankit Garg , Eddie Phillips , Praveen Kaligineedi , Jeroen de Borst , linux-kernel@vger.kernel.org, bpf@vger.kernel.org, stable@vger.kernel.org Content-Type: text/plain; charset="UTF-8" When XSK pools are enabled after an XDP program has already been loaded, XSK pools are registered on pre-existing queues before queues are re-created with the XSK pool fully registered in DQ RDA mode. This can lead to a race condition between the RX NAPI and the control plane thread wherein a pre-existing queue sees the live XSK pool and attempts to use recycled buffers not backed by XSK buffs for AF_XDP ZC traffic. This causes the following kernel panic to occur when attempting to DMA map a NULL XSK buffer: BUG: kernel NULL pointer dereference, address: 0000000000000050 ... RIP: 0010:gve_rx_post_buffers_dqo+0x99/0x190 [gve] ... Call Trace: gve_rx_poll_dqo+0x4d9/0xf10 [gve] gve_napi_poll_dqo+0x76/0x170 [gve] __napi_poll+0x28/0x160 net_rx_action+0x2a0/0x350 handle_softirqs+0xd4/0x280 ? sort_range+0x20/0x20 run_ksoftirqd+0x2d/0x40 smpboot_thread_fn+0xd5/0x1d0 kthread+0xd7/0x100 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x1f/0x30 The XSK pool should only be registered with current queues if XSK buffers are allocated on-the-fly, as is the case in QPL mode. Fixes: c1fffc5d66a7 ("gve: implement DQO RX datapath and control path for AF_XDP zero-copy") Cc: stable@vger.kernel.org Reviewed-by: Jordan Rhee Reviewed-by: Tim Hostetler Signed-off-by: Joshua Washington --- drivers/net/ethernet/google/gve/gve_main.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c index 9cc343a16271..b9bcdc7619b2 100644 --- a/drivers/net/ethernet/google/gve/gve_main.c +++ b/drivers/net/ethernet/google/gve/gve_main.c @@ -1654,20 +1654,18 @@ static int gve_xsk_pool_enable(struct net_device *dev, if (!priv->xdp_prog || !netif_running(dev)) return 0; - err = gve_reg_xsk_pool(priv, dev, pool, qid); - if (err) - goto err_xsk_pool_dma_mapped; - - /* Stop and start RDA queues to repost buffers. */ - if (!gve_is_qpl(priv)) { + if (gve_is_qpl(priv)) { + err = gve_reg_xsk_pool(priv, dev, pool, qid); + if (err) + goto err_xsk_pool_dma_mapped; + } else { + /* Stop and start RDA queues to repost buffers. */ err = gve_configure_rings_xdp(priv, priv->rx_cfg.num_queues); if (err) - goto err_xsk_pool_registered; + goto err_xsk_pool_dma_mapped; } return 0; -err_xsk_pool_registered: - gve_unreg_xsk_pool(priv, qid); err_xsk_pool_dma_mapped: clear_bit(qid, priv->xsk_pools); xsk_pool_dma_unmap(pool, -- 2.55.0.1082.g2b9226bbc0-goog