From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f200.google.com (mail-pf1-f200.google.com [209.85.210.200]) (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 CD7863DC4D3 for ; Fri, 14 Aug 2026 23:49:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.200 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786751367; cv=none; b=VBnXPxhYNDQ98OUd6B5G8/f7rwnWnEPWpQHIxifwbLO0V3kt+CD1na/QYMr9VuVSFXC8Jx7/e398f9nLCUqActZIcG9i/0WguEwJ4n7ifwZhRxXrngjH10Pf0qUpk7AqMBoq4BPCgvcj6OjN7REmqYtT9akjiYAmmuF9tOitQ34= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786751367; c=relaxed/simple; bh=/ECkwXTcbS/nrl8o0PNyBOTEnaTt4kJMaOMMUVKH7IE=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=HCAKCwLVSdSrpQZGVTJaTAOpwN36KW4iNXPAYT3fuo6fHlHAiN8arkIcK/zpwPFnUvVbJmAZ6dY6rcoWJiRImVYN7WCFxZGdl2J83AOZOTKGX7dc0Mty00aPno0RCo3eYpVSXvdlUbWJMwHd3xYbLoV8PELORxW90LRyzEatEpU= 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=tgDEd7KH; arc=none smtp.client-ip=209.85.210.200 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="tgDEd7KH" Received: by mail-pf1-f200.google.com with SMTP id d2e1a72fcca58-848d21bbb55so2060768b3a.0 for ; Fri, 14 Aug 2026 16:49:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1786751359; x=1787356159; 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=Nj+GAK80Vf0LtjqMeVaepRws/HUe3sjBCweZwIjqkZ0=; b=tgDEd7KHYjeQu+VsJLq06dlX9H1wiZaOhcJChoNHiN+02KEUdrayjaa12rNbt2erZm gY5hbxKLmkdcKoS813c+PjztaccHq6biPGAlx/jNtKzmABLDE8c7WcNOXQZC/ni7hBPO pU3u/pgQOipyU79vhH/I8fQntF8ZYYc7+/C3QCG9juag2Uz7kyp3rXRy55QNjW2hQQZt rxDNA3miGierylYJeiCRsSmXdXzQSmCsh6mKzZifprkqliPkTBDwnv8Upc88axtHDyVY KKEEJfWU81MzHJ7JJPu4+XuJRWdSRPHPUeI9UuTn9MDiIPQ9bUNKvgGp2i62SLKmSoiq ZZVg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786751359; x=1787356159; 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=Nj+GAK80Vf0LtjqMeVaepRws/HUe3sjBCweZwIjqkZ0=; b=F9hP8mo9GCt5Nns0pVaPxwJph/i96UA+znI2E2iik+HZI4UjdG+Kkif2BlYheh9iSi b5SkWwtGyFNjXIHZMAi+RD/8fxWZRXpgWot8el3F71yCPz0ocJ4rk7hDQZY78LxZ3N/g oduzIv5ZjNHOidFCcn27DzA1PBmZI+Qq6AQTfCaQHKz7E8/Zp2kBNUUQgiAp0q/4NrdH nzdSH/28y167UVfeO7T3wZc3uBD1ip1wVAyPG5qAocZHlH/OP2OIf5UiLoy1MwHwDij1 HXftGTbb+aHNSXRDNPcazSkNYYplpo3Ncq/6OeJIMkohwutMaTnRkI7sUa4zE7B+IZHm 6A9g== X-Forwarded-Encrypted: i=1; AHgh+RqWGMoEI+tGunf2RDRLkAWZYNqU0dLiewEMQTh4Bqq0GzCrtJ8Ew2DVyb0VU+R64ehNroWlxEfcDzuyPzg=@vger.kernel.org X-Gm-Message-State: AOJu0YwrEcvX8W2z0q0IK2MFHVwviFmQSmwqzqUvr8d71UmaTfJRUwdS QAzlNiQhvGhgLfK2blea8lG8RPGv/re6k9RtAorEKpHfbM4TEyija32NBLue//d/PgOz8hGHyap OE5i86Yvkob4ucQ== X-Received: from pfes10.prod.google.com ([2002:aa7:8d4a:0:b0:848:4642:f1d3]) (user=joshwash job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:3ccf:b0:845:40d1:87fa with SMTP id d2e1a72fcca58-84fde20e2a4mr9752920b3a.25.1786751359066; Fri, 14 Aug 2026 16:49:19 -0700 (PDT) Date: Fri, 14 Aug 2026 16:48:43 -0700 In-Reply-To: <20260814234845.773189-1-joshwash@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260814234845.773189-1-joshwash@google.com> X-Mailer: git-send-email 2.55.0.691.gc56d675ccc-goog Message-ID: <20260814234845.773189-5-joshwash@google.com> Subject: [PATCH net 4/6] 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 , Jordan Rhee , Willem de Bruijn , Ankit Garg , Tim Hostetler , Praveen Kaligineedi , Jeroen de Borst , Stanislav Fomichev , 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 e4d78ae52daf..453b304016b6 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, -- 2.55.0.691.gc56d675ccc-goog