From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f175.google.com (mail-pg1-f175.google.com [209.85.215.175]) (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 A7C231BE86D for ; Wed, 14 Aug 2024 20:22:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.175 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723666946; cv=none; b=CCSJHyy8M/xxVxItZ12y7XoOenM2voU7rXA6T5Mt4QKWJK48860xYO9DG5niXs08GseKnNZBiFreiPWRb3o+cIGmqC83q218cuTWYWOBGPle5BtJv8r5bxvVuFCnpfSwhrTZ7g5bzqcnyTCo4fuSqN51/fVQvTMP+SLCEI3laAE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723666946; c=relaxed/simple; bh=5SRnXsvGe0ks1PPk2d6iR2E36xrdoQ/xKFVPBkEc0G8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=I3W9kG3Ivg+WIQSsf/L5CShy1MKN3tLG12Fla87AZB0l2sLhIdUEsNERygcPBAyGGMmzTu0ihSa4R3amYxXrVNPUnWBXjHo9r5A8C/4FHho2jwcmkj7s0zZgZu8oxNIUiY/Wvn/hKOrT62scy+gaBjUhDdnLA0RnTu/QpT1beqo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk; spf=pass smtp.mailfrom=kernel.dk; dkim=pass (2048-bit key) header.d=kernel-dk.20230601.gappssmtp.com header.i=@kernel-dk.20230601.gappssmtp.com header.b=fwhs2YKg; arc=none smtp.client-ip=209.85.215.175 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kernel.dk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20230601.gappssmtp.com header.i=@kernel-dk.20230601.gappssmtp.com header.b="fwhs2YKg" Received: by mail-pg1-f175.google.com with SMTP id 41be03b00d2f7-75abb359fa5so44946a12.0 for ; Wed, 14 Aug 2024 13:22:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1723666943; x=1724271743; 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=3qrLHDtIlgRrYjlbN2SIttaAtVkHKsw4QroqjhY2qOA=; b=fwhs2YKgxuOfojl6WgZszKAS5tEhCkLnpAN5NGBczmLdI4grvofulZLsuyIvozQ+7a +hgwttuGNTh7q9OFX3jm9yiwzEZN5Sl5bncFYFN544jc5rdKlMoVM/b2hYdPsvSffLRJ rThwPfX88UdOZkg6DANdhzUMNgmt2K04xi6WIXhne4UUFqHUKnblPXgys5uXcUqUwcs1 lGFj50xjyjNBfuiRs9l5AAGudUi24qB35H3j7fNaYNLGBEGQAwLUz6U6J8GOISTOcKlE JXb9kByScn+BgyoNPy/T1ala5Abcs89KhPB/Uaxy1FhLxN456pm7moWEAO77HtddLah+ ZtTA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1723666943; x=1724271743; 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=3qrLHDtIlgRrYjlbN2SIttaAtVkHKsw4QroqjhY2qOA=; b=Rt+dSTIZSeS2bbt4z8H8slNOW8sK0z8jSypOwR9UNG0g/hteEZivZcqQL0GDRroq+M KVT4hv3s3xrJ6618qIlCxDRfVXGudpUAgP5SF87T1UQOlc/mnrMHPScaqJqY0EF9c2CR ZSXIHOWmw9Y+eKVktYtKVGkqMAS3jgLqgwfKHtgnvSWkwO8wYAkje3lwZ6jvHuWgwjOa qOEwZPu/iA9H51kdEs+Vm7tRXY/NWAo4eQ/FmKGD4oaEBusEpuB0keSOgUrAVPvuFU/L +m0Y2RC65l6/HkNy45YZS1lO2jk3seZyyxYmt03R4DTgIdngspwuONa0bkMUHtjhS3yY s9bg== X-Forwarded-Encrypted: i=1; AJvYcCUGC0mBNX56ng9I234A6MgGTkhb7pPAfmXDFxlkQzsbfs3JIcIF1lodMTucFvcckqc/LJ8z00hlTM5ZfRE=@vger.kernel.org X-Gm-Message-State: AOJu0YyFtHPS6rwaCIytaLKA8JwYPmGvqms/ncUX0w8wnIrHGJ22/AM0 B4s9MYPpk5XynsnTvgIrGNcZHwfNKBCPc+Ymg38sAbMD9kHIOqBGaRQrxsqaFo8= X-Google-Smtp-Source: AGHT+IHvS4UxsLTCsRRg68/apHusWWi9hP1XGhri9rFG6yGlwDroEV/2XrWn3KKUdwV+vsDuC1Zbjg== X-Received: by 2002:a05:6a00:9446:b0:70a:efec:6b88 with SMTP id d2e1a72fcca58-7127831d8e9mr331374b3a.3.1723666942573; Wed, 14 Aug 2024 13:22:22 -0700 (PDT) Received: from [192.168.1.150] ([198.8.77.157]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-710e5ac4184sm7717850b3a.215.2024.08.14.13.22.21 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 14 Aug 2024 13:22:22 -0700 (PDT) Message-ID: <6e729890-7374-4335-ab7d-ead00775057e@kernel.dk> Date: Wed, 14 Aug 2024 14:22:20 -0600 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] block: Fix potential deadlock warning in blk_mq_mark_tag_wait To: Bart Van Assche , Li Lingfeng , hch@lst.de, jack@suse.cz, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Cc: yukuai1@huaweicloud.com, yukuai3@huawei.com, houtao1@huawei.com, yi.zhang@huawei.com, yangerkun@huawei.com, lilingfeng3@huawei.com References: <20240814113542.911023-1-lilingfeng@huaweicloud.com> Content-Language: en-US From: Jens Axboe In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/14/24 1:52 PM, Bart Van Assche wrote: > On 8/14/24 4:35 AM, Li Lingfeng wrote: >> When interrupt is turned on while a lock holding by spin_lock_irq it >> throws a warning because of potential deadlock. > > Which tool reported the warning? Please mention this in the patch > description. >> >> blk_mq_mark_tag_wait >> spin_lock_irq(&wq->lock) >> --> turn off interrupt and get lockA >> blk_mq_get_driver_tag >> __blk_mq_tag_busy >> spin_lock_irq(&tags->lock) >> spin_unlock_irq(&tags->lock) >> --> release lockB and turn on interrupt accidentally > > The above call chain does not match the code in Linus' master tree. > Please fix this. > >> Fix it by using spin_lock_irqsave to get lockB instead of spin_lock_irq. >> Fixes: 4f1731df60f9 ("blk-mq: fix potential io hang by wrong 'wake_batch'") >> Signed-off-by: Li Lingfeng > > Please leave a blank line between the patch description and the section > with tags. Please just include the actual lockdep trace rather than a doctored up one, it's a lot more descriptive. And use the real lock names rather than turn it into hypotheticals. -- Jens Axboe