From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f47.google.com (mail-wm1-f47.google.com [209.85.128.47]) (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 D2C13224891 for ; Wed, 26 Nov 2025 17:49:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.47 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764179387; cv=none; b=LLlNFgT0SJoEvAMmmPqzIus2TzA7qANAkCM+UoZwu8sdzWKnxQqJ5rb33nMNKLnA8GOJCmeJMT18CM4rfna4aHitzDtP5NpCG90TEiKA2aqV0ikHwXat4mw543ciOVNcMJFHsrY20DmGa+4yLo37+l+moYbRsJGKfN4UPpGsVuA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764179387; c=relaxed/simple; bh=EZRgUZjkuoZ3cQ6aAEafNzlykTDgpLExKuhA6htK22E=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=lB4tLPir8KjQyQJ+OQqF2++AFIIloedkoVLlCfPLidAg9MdD1AGkD/SzC7r+3LudEhqyLv3bVbFltNuu5IAv0FZJsIIksqDpBAVxQ2oFZeD8bDtvSChd5xH2UPEQMLXTX7kFbfuhmGcq+KOzrd50RsJ5wI5v0Wy9cMjLKen+QL8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org; spf=pass smtp.mailfrom=linaro.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b=KaHyg0Kx; arc=none smtp.client-ip=209.85.128.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="KaHyg0Kx" Received: by mail-wm1-f47.google.com with SMTP id 5b1f17b1804b1-4779cb0a33fso68422465e9.0 for ; Wed, 26 Nov 2025 09:49:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1764179384; x=1764784184; darn=lists.linux.dev; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=/LOZIxc4c+5C8jrBtkGFP92aBtdLlWqGsR9z3cYxzug=; b=KaHyg0KxSaxKYC6M07Jq/Z6+prH+A5euMkqI0I6ab2Eaxe4da+5HR0pfYooy0O2j3Q /JNR0IWxf0QwRM7Jxhx8ZaZcQHVvKMwrrbzhGdaTvgZJgVr0PuOs8RVML/yxqGfx/gAj WPtv4NaL2c77tCNdl2+TwxibUkjvH5lfSSuHzZjZAnbjNSSMKIrXcjsmVuGswOA7mVhJ INTewIC/Ej5KH8brKxnrA1HcR1Hw9gPIzLPJFXwiaCD0FB+QC+N38Bn6LvZVfx7zsJwW AsWI2YWd35FbD8NRR6WchvKZtq83uAjalHYMRxRgSnxC1jF/+DIwXZZ+pb8B3ACaMkgC R+tw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1764179384; x=1764784184; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=/LOZIxc4c+5C8jrBtkGFP92aBtdLlWqGsR9z3cYxzug=; b=i4v3hBLvpPU/jnBqsfSgDzecnFMmYVfP4rkzK0hQBCxuauvUjKC8Q6JbdFzrXdIALo 6ShwGG9FkjH/bon+SpLWgwTuTQbiO6X5yiISUxgDYZvUG8aZW9hbxfIFKotkNyPzp+zO A3gNg0Iz/3Jlh3QiraZiMGX7DVqU/Hi+UiLQ4cKo4jeZYm0Xh3k7GaR4FjJywzJjipZj xwnLIPd8r5vvPKqNxVN/xgI9Xp0Q2tnR8F9u+/GG6JPzEG6uKELwiqrx3ZQABlGUVi78 ZnW4Jkya98YRbK5TYulxft31fqjikw66VhlLdPEYZiY54jlG40cX7lb5G9uWwC9G4sFa GV2Q== X-Forwarded-Encrypted: i=1; AJvYcCWEnoDPFAFsG7TX0xBWPPb9gp6BStwSE58s2U+Z1H5mp+ikusen3qel60JafrE7U4GFOK+FH7e35L5mix3P@lists.linux.dev X-Gm-Message-State: AOJu0YzCC5/hTIG6meX4LiPCI7fL/aPS+HXt3ujgOwgU0cBj2M3LEb4X RsClwHr1oltpGIVAkdD+2zGMa6BOM0VXyeCpjQaKaYUC/MMJqKigs74BdzU6RMBYTOg= X-Gm-Gg: ASbGncv53b0N6t1ahV6OxAuhztsXD4yJ3AVChFNbmF0vCTcb1VG2ta10F5qEETp+6hI jzKXMzydBNcXe99y9mmH1OgvZJ+YkBJsm/3TP/uAou1yITawX8X7Sk/EwOkELMs0LsIuNth0AsJ 2fnEqQCuVuL48t7uztL6+iIoYkKzv7HY9g6fq8qZTeEBQcdp0W2pYYpxQ0pHvwd64mre5TAbqO1 ykvcEp6zib4yzmSVX7LJSJKUXjU1X02/P4JHiNA0Ljph3k3jrklEydOGTAEYCraBcfMpyAnzgGI 0tmuF1Ig35DujZ0H90+zAYxNAu6dJNezn2XMvYRDOWRhN3cMOLcyObnUACRsmL0dPJtm9RmcJv2 IDmOScHagM4bt37hM3yO8q2Z+PiEl/c5O+guBUvjT7JZsHMPYZen6VfRSiMukD1jVuwdkC+VU7l aOn0C65PpE/l32gi0= X-Google-Smtp-Source: AGHT+IFh53QIi+oxLq7ptVsKtwjm1PxcTE77Pu2H4HuthrAKa3ytxneiA49pMvTvJJmFtJEUGhPXJw== X-Received: by 2002:a05:600c:1909:b0:477:b642:9dc6 with SMTP id 5b1f17b1804b1-477c020137fmr201952805e9.34.1764179383830; Wed, 26 Nov 2025 09:49:43 -0800 (PST) Received: from localhost ([41.210.155.191]) by smtp.gmail.com with UTF8SMTPSA id 5b1f17b1804b1-479040d3c72sm49384375e9.6.2025.11.26.09.49.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 26 Nov 2025 09:49:43 -0800 (PST) Date: Wed, 26 Nov 2025 20:48:30 +0300 From: Dan Carpenter To: Pavan Kumar Yalagada Cc: parthiban.veerasooran@microchip.com, christian.gromm@microchip.com, gregkh@linuxfoundation.org, laurent.pinchart+renesas@ideasonboard.com, hverkuil+cisco@kernel.org, linux-staging@lists.linux.dev Subject: Re: [PATCH v2] staging: most: video: prevent probes during component exit Message-ID: References: <20251126155910.32694-1-pavankumaryalagada@gmail.com> Precedence: bulk X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251126155910.32694-1-pavankumaryalagada@gmail.com> On Wed, Nov 26, 2025 at 10:59:10AM -0500, Pavan Kumar Yalagada wrote: > @@ -453,6 +455,9 @@ static int comp_probe_channel(struct most_interface *iface, int channel_idx, > struct most_channel_config *ccfg, char *name, > char *args) > { > + if (comp_exiting) > + return -EBUSY; > + > int ret; > struct most_video_dev *mdev = get_comp_dev(iface, channel_idx); You've added this check above the declaration block which is ugly. But what would happen if comp_exiting is false when we check here but it's true by the time we get to the line which says: list_add(&mdev->list, &video_devices); There would still be a race. > > @@ -553,6 +558,7 @@ static int __init comp_init(void) > > static void __exit comp_exit(void) > { > + comp_exiting = true; > struct most_video_dev *mdev, *tmp; In front of the declaration block. > > /* > @@ -575,7 +581,7 @@ static void __exit comp_exit(void) > > most_deregister_configfs_subsys(&comp); > most_deregister_component(&comp); > - BUG_ON(!list_empty(&video_devices)); > + WARN_ON_ONCE(!list_empty(&video_devices)); When the race condition is fixed, then we can just remove this. regards, dan carpenter