From nobody Fri Dec 19 15:18:23 2025 Received: from mail-pl1-f177.google.com (mail-pl1-f177.google.com [209.85.214.177]) (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 A14C1194ACA for ; Wed, 4 Sep 2024 09:06:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.177 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725440764; cv=none; b=OuehnuFi5vEz90wnnhMPVhNSNIQ/qaGhXtDATIx5DxzeoPinGNx2mCZw3bqSZGIk+Q0EGm5b604rtNEcE0jtIP0rvuKWdLtR0HTxEl9EQf/IH+AZuzlYebj8Q1okVjG/ahX+V6uEWDfbEonGCFvcIjySQYEGsHG1WkYijwEAiZ8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725440764; c=relaxed/simple; bh=jDBq4Ng87U5vWLCtGk/fTMd743FQxW3hZo2L1hthBoE=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=fHf4mceJkvIwaycgiDhPHAwdY0fga5Talo+3AOcIr4ASg6rp4NHpGM8dNHy9qa5yAVfZsyB4caTL/1q/Y184zOYCQ2ZG3hTX2yuzfGf14oXMaxCfLAGIcuWeuy1Wl9zedntHqYnd3n5VUcBLQNdd2TJC3vVenSn2sOdINpxbFqQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=broadcom.com; spf=fail smtp.mailfrom=broadcom.com; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b=Qr6Ybpzl; arc=none smtp.client-ip=209.85.214.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=broadcom.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=broadcom.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b="Qr6Ybpzl" Received: by mail-pl1-f177.google.com with SMTP id d9443c01a7336-2068a7c9286so19240485ad.1 for ; Wed, 04 Sep 2024 02:06:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; t=1725440762; x=1726045562; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=s2WW0Uh5MFwXmQymV6WF9+7CjegjBeXRtTOVI/P2KHw=; b=Qr6YbpzlxeEIyLeLCA+SVeoRtFEYXxM0RirkVD9YcGfPck5FEvduwNo3Tj5OXKsQLH ymXqY+DG1JiAGEHJPj9W/ZJldBlDvIYJConhm8pZ5i0xcFKJ4ebDGTgSb1S6BqC8vdv5 ii7/vrFRWaLy6VX7nLz3h+phRCPRt462aNnCA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1725440762; x=1726045562; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=s2WW0Uh5MFwXmQymV6WF9+7CjegjBeXRtTOVI/P2KHw=; b=vgB+K41qIUJse9z1xS5eLrdGMJkf4ihkdYKE9Fh+gaqJsTRljG8Kj1gk7Rstn7ViO7 FeinMmhLjBYajI7bhGsiwgrNPe0SiQooi/x4fmRrQNvqZejUC8Nwa63TMMwQf9mE0OXo KBxYNXO5PhOUhR/34kWwTcLAUYKM7oWhvshzzGLBqElG3B6T2+aUfPmyw9/hwfLptwbl CGL8Abw1hQXCQUUjh3uyi7XbW+KfngMKqCpH2aBirj9b91wGb4dAgFKae4soYllVA3cs Y3E0qjoWFTy8KzsoEcieCgokzzNbdGGcPm+6ZzymCVXJeV6/kButMlC0sj2TfceHGrVy izlg== X-Forwarded-Encrypted: i=1; AJvYcCVS+9AQvh5Y04104pBAly6x9FeoeJTCq1ua3UrcQ5nfus8F4GXtUBHPmq5nAVO0Z2MnKW7uWK64urA9s0A=@vger.kernel.org X-Gm-Message-State: AOJu0YzqzJVUoiJaWeSNzf6/vDAgTC1TS5pLqg6dxPNSFwmBGlV2pgOO W17uFxw9Am54s9+cM7xK3jY8zRiKkKy8HRi+9glIRLsSKuKOx7WOsKuWv1/l7Q== X-Google-Smtp-Source: AGHT+IEBsx5mNF1aMY3Pulj+ByK6nJUa4wjeFTWqbIBmNujyGWU5qrkO+va3WqSnQ1IWgwTrsH7VXw== X-Received: by 2002:a17:902:ce10:b0:205:8456:df0c with SMTP id d9443c01a7336-2058456df32mr82458875ad.26.1725440761785; Wed, 04 Sep 2024 02:06:01 -0700 (PDT) Received: from shivania.eng.vmware.com ([66.170.99.1]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-206aea52a8asm9670135ad.182.2024.09.04.02.05.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 04 Sep 2024 02:06:01 -0700 (PDT) From: Shivani Agarwal To: stable@vger.kernel.org, gregkh@linuxfoundation.org Cc: mst@redhat.com, jasowang@redhat.com, xuanzhuo@linux.alibaba.com, eperezma@redhat.com, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, virtualization@lists.linux.dev, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, ajay.kaher@broadcom.com, alexey.makhalov@broadcom.com, vasavi.sirnapalli@broadcom.com, Breno Leitao , Heng Qi , Sasha Levin , Shivani Agarwal Subject: [PATCH v5.15] virtio_net: Fix napi_skb_cache_put warning Date: Wed, 4 Sep 2024 02:05:53 -0700 Message-Id: <20240904090553.15076-1-shivani.agarwal@broadcom.com> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Breno Leitao [ Upstream commit f8321fa75102246d7415a6af441872f6637c93ab ] After the commit bdacf3e34945 ("net: Use nested-BH locking for napi_alloc_cache.") was merged, the following warning began to appear: WARNING: CPU: 5 PID: 1 at net/core/skbuff.c:1451 napi_skb_cache_put+0x82/= 0x4b0 __warn+0x12f/0x340 napi_skb_cache_put+0x82/0x4b0 napi_skb_cache_put+0x82/0x4b0 report_bug+0x165/0x370 handle_bug+0x3d/0x80 exc_invalid_op+0x1a/0x50 asm_exc_invalid_op+0x1a/0x20 __free_old_xmit+0x1c8/0x510 napi_skb_cache_put+0x82/0x4b0 __free_old_xmit+0x1c8/0x510 __free_old_xmit+0x1c8/0x510 __pfx___free_old_xmit+0x10/0x10 The issue arises because virtio is assuming it's running in NAPI context even when it's not, such as in the netpoll case. To resolve this, modify virtnet_poll_tx() to only set NAPI when budget is available. Same for virtnet_poll_cleantx(), which always assumed that it was in a NAPI context. Fixes: df133f3f9625 ("virtio_net: bulk free tx skbs") Suggested-by: Jakub Kicinski Signed-off-by: Breno Leitao Reviewed-by: Jakub Kicinski Acked-by: Michael S. Tsirkin Acked-by: Jason Wang Reviewed-by: Heng Qi Link: https://patch.msgid.link/20240712115325.54175-1-leitao@debian.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin [Shivani: Modified to apply on v5.15.y] Signed-off-by: Shivani Agarwal --- drivers/net/virtio_net.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index bd0cb3a03b7b..d8138ad4f865 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1548,7 +1548,7 @@ static bool is_xdp_raw_buffer_queue(struct virtnet_in= fo *vi, int q) return false; } =20 -static void virtnet_poll_cleantx(struct receive_queue *rq) +static void virtnet_poll_cleantx(struct receive_queue *rq, int budget) { struct virtnet_info *vi =3D rq->vq->vdev->priv; unsigned int index =3D vq2rxq(rq->vq); @@ -1561,7 +1561,7 @@ static void virtnet_poll_cleantx(struct receive_queue= *rq) if (__netif_tx_trylock(txq)) { do { virtqueue_disable_cb(sq->vq); - free_old_xmit_skbs(sq, true); + free_old_xmit_skbs(sq, !!budget); } while (unlikely(!virtqueue_enable_cb_delayed(sq->vq))); =20 if (sq->vq->num_free >=3D 2 + MAX_SKB_FRAGS) @@ -1580,7 +1580,7 @@ static int virtnet_poll(struct napi_struct *napi, int= budget) unsigned int received; unsigned int xdp_xmit =3D 0; =20 - virtnet_poll_cleantx(rq); + virtnet_poll_cleantx(rq, budget); =20 received =3D virtnet_receive(rq, budget, &xdp_xmit); =20 @@ -1683,7 +1683,7 @@ static int virtnet_poll_tx(struct napi_struct *napi, = int budget) txq =3D netdev_get_tx_queue(vi->dev, index); __netif_tx_lock(txq, raw_smp_processor_id()); virtqueue_disable_cb(sq->vq); - free_old_xmit_skbs(sq, true); + free_old_xmit_skbs(sq, !!budget); =20 if (sq->vq->num_free >=3D 2 + MAX_SKB_FRAGS) netif_tx_wake_queue(txq); --=20 2.39.4