From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f182.google.com (mail-pf1-f182.google.com [209.85.210.182]) (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 49D121F4CBA; Thu, 3 Apr 2025 10:43:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743677016; cv=none; b=j2NW4gv1Bx/tFSMeMntu82tiAmamTOb25OB9RgumKlfkMsJzjQoarB6X9G419V2IDGjkcEDbPwatXZUCmLeF85E8Thb4Z9jSp3PI830s1wiW+7jz13hQOaNeeqRF4YRSFhVtayX+vMIQA9sZIpsZXVo8jTrxN34+D+97pb4RvAc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743677016; c=relaxed/simple; bh=BnDJa1NQQgaQiyi+V0Ba6o9o2I6eOeRoTuZjMFY/ckE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=iUzRVXFQf2NilfkQT89ULipLSdjferi3oYEl2vpxcA79QvLDIl7ODN8zqS9Wti528Lbm6DZs2SHN7N0CtNAHEI5Tpmr/tMmq7Qw0VbnFmjBxhirBSzBkvX0U9p/AAPP2fj150ZnaeUFE7pn7APmpm8KcWa3CRTE4xfuIb+fpR9M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=IwN3+68V; arc=none smtp.client-ip=209.85.210.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="IwN3+68V" Received: by mail-pf1-f182.google.com with SMTP id d2e1a72fcca58-736b350a22cso585955b3a.1; Thu, 03 Apr 2025 03:43:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1743677014; x=1744281814; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=XKfPpP5X7BAGuDFo2uD9oJkA83aeZkArrNDesmfrThk=; b=IwN3+68VtAnEcYhnRXG0Mmoa92k6uJM9FpJEPqoS/bITgyfQWOtk4fxp7CxD6Z2UOg qtnm0zUT66QEVrqER8FNiM0GCIYbEJvtJr6aE7yVcvxr+0kF2aTCDYKptgE94EawMAXE X8KHUvnmiVBt6ECI1CrMc2ZpNCUaLd/yXQs+advW3P0FUX5dJgENRBKYAof8weF/sF5B suoU93xZaoX6wHUNLd6mR+gAXAUylKbQmtGhEDMXWXumPFA+W2yFdXv3nqmSGTsIdkVT odhtFmnu/I7pJYSJvHN6r3s2Aj6IF0QTepimLClyKRUKV3x3WdwrAxl2XDYVvpxD1DHT zahw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1743677014; x=1744281814; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=XKfPpP5X7BAGuDFo2uD9oJkA83aeZkArrNDesmfrThk=; b=Z2iZObPc9jTLHfkrMp97EXy56gC3aibEEsVzW2pTV8zEvtTGMzcwzznqJoNrtLrwSM ewfFKsrvTePpxLikcEXwWbKrbqAZQ8XGfu6VayRuj8xJ5YT8OzbSk7UQNNEK6T8xPC7v iiE4mL3O3hpx0PRHmYfsewjPbdrnUIziG0b9pjCB58wZfU8XBR5BmxJR1ydMtEvarwr9 vxGnGqFEvlhlh6vVEVmZJZiIcfoVUb1FS5wP4361Cyps0Kpxa6UclwIZRuDbUL2lLCut tL1KvqyyRAqWaL1GoZP+PEWAqVFb1S1HPxmPibu1jWK/MjjTFdcGrBrXXUo+/juWU27T Q1sw== X-Forwarded-Encrypted: i=1; AJvYcCUqB7Uz/SLahjPzd8FBOSAHQjeb1UMZrfweXpwKSDtwlfNc9UzNzyloUFVC9lj2KbJliMBewi0iaGZGysXR@vger.kernel.org, AJvYcCW4T6SxcA9J1oURZbu1qbVrZOfdptTiCUOVBdl9lMmNZeVgwl+vQztBCHvhY2xV2rPqrs0=@vger.kernel.org, AJvYcCWgnOnP66K77iY8bWVhd/ZiHl2eglhUnm7Hmh/XHNVUB/81mXoMi1XoGapY7otPfZSD0Skdrwrs@vger.kernel.org X-Gm-Message-State: AOJu0YxILkt1DwLZds4oXiT9Oq4qG8N0Pd0HlID2O95JS9nMOieq+Sdo 1Os+okRdZzzqY1sz5gtTpXTgXiqVHnW1hQ1eEsDLVU31lMkny0L9 X-Gm-Gg: ASbGncuAdaVmrejkWSjkPX5ARAZIUiaFSLuDSv9ilSxR/eGuq2DtbzFcbItnqCube/6 wvUY2cVslREZ3k5EqxXvui3MB4bimjrxAxdHTmDV1W3botOktjaIIhVLq0eDvasd6U5kWGf6JR3 AB9CtcOprkp+MdOLtMmRXbDL+D60RgtHnZlGTi2FyD8+fkiaRbIbJb5TnTYrqqTcdY+W+vUcygL yk2QQMn1zak/cH6648K8kwZw5y5PyZqvrgPg0A1Wa37gJ91ujcADX9SsBtpltTD/RyNd7vkz58m rpziL/reBoBVoWrZJgAnWadr8t9uwr0GpdUSodL9OSyfP4BERX2DoyyhD1PiuwayCHND9TIbDH5 2JlKTLLii8oLVmzi5Wba6Auw= X-Google-Smtp-Source: AGHT+IHkcCi0YR0D+hOGCuMNoTiX/WY5jnF7Ek8IM7ApPidPGWeW9JEmR3voupoks8wnoR3rCxGzhw== X-Received: by 2002:a05:6a00:399d:b0:736:53bc:f1ab with SMTP id d2e1a72fcca58-739d9e96e15mr2649550b3a.12.1743677014350; Thu, 03 Apr 2025 03:43:34 -0700 (PDT) Received: from ?IPV6:2001:ee0:4f4e:bd30:2142:e08e:e207:d31c? ([2001:ee0:4f4e:bd30:2142:e08e:e207:d31c]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-739d9805a00sm1144603b3a.81.2025.04.03.03.43.28 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 03 Apr 2025 03:43:33 -0700 (PDT) Message-ID: <8aad5ff9-6eab-411d-9569-9a2303561ac0@gmail.com> Date: Thu, 3 Apr 2025 17:43:26 +0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] virtio-net: disable delayed refill when setting up xdp To: virtualization@lists.linux.dev Cc: "Michael S . Tsirkin" , Jason Wang , Xuan Zhuo , Andrew Lunn , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , =?UTF-8?Q?Eugenio_P=C3=A9rez?= , "David S . Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org References: <20250402054210.67623-1-minhquangbui99@gmail.com> Content-Language: en-US From: Bui Quang Minh In-Reply-To: <20250402054210.67623-1-minhquangbui99@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 4/2/25 12:42, Bui Quang Minh wrote: > When setting up XDP for a running interface, we call napi_disable() on > the receive queue's napi. In delayed refill_work, it also calls > napi_disable() on the receive queue's napi. This can leads to deadlock > when napi_disable() is called on an already disabled napi. This commit > fixes this by disabling future and cancelling all inflight delayed > refill works before calling napi_disabled() in virtnet_xdp_set. > > Fixes: 4941d472bf95 ("virtio-net: do not reset during XDP set") > Signed-off-by: Bui Quang Minh > --- > drivers/net/virtio_net.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 7e4617216a4b..33406d59efe2 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -5956,6 +5956,15 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, > if (!prog && !old_prog) > return 0; > > + /* > + * Make sure refill_work does not run concurrently to > + * avoid napi_disable race which leads to deadlock. > + */ > + if (netif_running(dev)) { > + disable_delayed_refill(vi); > + cancel_delayed_work_sync(&vi->refill); > + } > + > if (prog) > bpf_prog_add(prog, vi->max_queue_pairs - 1); > > @@ -6004,6 +6013,8 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, > virtnet_napi_tx_enable(&vi->sq[i]); > } > } > + if (netif_running(dev)) > + enable_delayed_refill(vi); While doing some testing, it look likes that we must call try_fill_recv to resume the rx path. I'll do more testing and send a new v2 patch. > > return 0; > > @@ -6019,6 +6030,7 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, > virtnet_napi_enable(&vi->rq[i]); > virtnet_napi_tx_enable(&vi->sq[i]); > } > + enable_delayed_refill(vi); > } > if (prog) > bpf_prog_sub(prog, vi->max_queue_pairs - 1);