From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=195.135.223.131 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794042603; b=K4nWa7W9Em3D5cGycas82ItkCoVlJ9xRLIsotxf5IiGHEeR6g6nHxTIZCP0CRKl1sGvJ YMpZTvzn4SY5yhPVw5ynGdxtzjZrI4lHeqtncqGTFdbCiV4lOSr2h6iK/xf7Upujz3QP4 VQP7WpIVhcilKTwFl01ajEQb4sdp+1tflTBS2+OGvuFU5DxfkJbsnTgoRlTdi797okt9Q RHoE4QaD3aWf+cH3R609YGRT2VBB8667HZafxT0AU54ZfphY4VxsGK80RUmfhHGOjhF/d 16AmGnXi9IV1QsfdtSvV70daBQl+R9jsoGDRQ4kahANGXjcYo+SOya1jQYpRWumiOBQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794042603; h=DMARC-Filter:Received:DKIM-Signature:DKIM-Signature:DKIM-Signature: DKIM-Signature:Received:Received:Date:Message-ID:From:To:Cc:Subject: In-Reply-To:References:User-Agent:MIME-Version:Content-Type: X-Spam-Flag:X-Spam-Level:X-Spamd-Result:X-Spam-Score; bh=58xoYRpmyM84qotsXl7y1fIxuq7D7HoXDGO7AOQk7B8=; b=L+uUmdrfKGRlf1SDDUEeUx9EGENKyEr4uemyoWj+hsvNJPwInQnLzTak18Ta5NiZucVJ dwRLBrM2BZrj3NGMmlUysKssMouWuvWwhCbHj6gE/CfPsEvN49JHZt2khd/4ZpPz5JFUc LjoOR4nkR1+bc+BWWiVmUmfg79FVmru6OeBizwkcaWbMCBhq00oroyPn5IxLkpq/aFmU/ 0j+3sxchu99c+xDm7P5GGHBXvgCOM0ey8AFHO3W7ti5mlUdUoSqaCZu8HpKiwo0xqhHuX Z1+liKKp2cKJSjUAfMhDxUc/GQicjlPHHlLDbKItuxQCVYi0a4lqxUdCpacj5laLi6w== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=suse.de; spf=pass smtp.mailfrom=suse.de; dkim=pass header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=mJWWyvfY; dkim=pass header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=3UNC+BYZ; dkim=pass header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=mJWWyvfY; dkim=neutral header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=3UNC+BYZ; arc=none smtp.remote-ip=195.135.223.131 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.223.131]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7A6F6606A326; Sat, 7 Nov 2026 09:10:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 7A6F6606A326 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=suse.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=mJWWyvfY; dkim=pass header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=3UNC+BYZ; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=mJWWyvfY; dkim=neutral header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=3UNC+BYZ Received: from imap1.dmz-prg2.suse.org (unknown [10.150.64.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 81FC01F797; Sat, 7 Nov 2026 09:10:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1794042600; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=58xoYRpmyM84qotsXl7y1fIxuq7D7HoXDGO7AOQk7B8=; b=mJWWyvfYsr63/+uPnI1Acj71p9RQDqItb/KG5jpvqpbmFugf5PzzrBGcig3lunfgqJqVIG e68KOnuVeT0vr+RXIBrZl7M0JFEt2uFozf7ZB0wT4b3JuojOHmssh1AMzCFS/3Nx6St0hQ 0VJBmHFmjH9wvacbDCpFtJslmoODTtY= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1794042600; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=58xoYRpmyM84qotsXl7y1fIxuq7D7HoXDGO7AOQk7B8=; b=3UNC+BYZBhU61l1PZhUR1NOyAM2IQlcUAvIpiM42+u5bwJuCy7HQTPd3ixz+S9OzBmpQg9 Z7YGPPPvvDzhugCQ== Authentication-Results: smtp-out2.suse.de; none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1794042600; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=58xoYRpmyM84qotsXl7y1fIxuq7D7HoXDGO7AOQk7B8=; b=mJWWyvfYsr63/+uPnI1Acj71p9RQDqItb/KG5jpvqpbmFugf5PzzrBGcig3lunfgqJqVIG e68KOnuVeT0vr+RXIBrZl7M0JFEt2uFozf7ZB0wT4b3JuojOHmssh1AMzCFS/3Nx6St0hQ 0VJBmHFmjH9wvacbDCpFtJslmoODTtY= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1794042600; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=58xoYRpmyM84qotsXl7y1fIxuq7D7HoXDGO7AOQk7B8=; b=3UNC+BYZBhU61l1PZhUR1NOyAM2IQlcUAvIpiM42+u5bwJuCy7HQTPd3ixz+S9OzBmpQg9 Z7YGPPPvvDzhugCQ== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 10929132C9; Sat, 7 Nov 2026 09:10:00 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id V2RiNOfq7mq7YQAAD6G6ig (envelope-from ); Sat, 07 Nov 2026 09:10:00 +0000 Date: Sat, 07 Nov 2026 10:09:59 +0100 Message-ID: <87eccxyplk.wl-tiwai@suse.de> From: Takashi Iwai To: Sreeraj S Kurup Cc: linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, perex@perex.cz, tiwai@suse.com, tiwai@suse.de Subject: Re: [PATCH v2] ALSA: control: Synchronize LED mode accesses In-Reply-To: <20261106183953.2762-1-sreekuttan2156239@gmail.com> References: <20261106180812.5097-1-sreekuttan2156239@gmail.com> <20261106183953.2762-1-sreekuttan2156239@gmail.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) Emacs/30.2 Mule/6.0 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-Spam-Flag: NO X-Spam-Level: X-Spamd-Result: default: False [-12.30 / 50.00]; SUSE_INTERNAL_BYPASS(-9.00)[]; BAYES_HAM(-3.00)[100.00%]; MID_CONTAINS_FROM(1.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; RCVD_VIA_SMTP_AUTH(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; MIME_TRACE(0.00)[0:+]; ARC_NA(0.00)[]; TO_DN_SOME(0.00)[]; FREEMAIL_TO(0.00)[gmail.com]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; TO_MATCH_ENVRCPT_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_FIVE(0.00)[6]; FROM_EQ_ENVFROM(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; RCVD_TLS_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:helo] X-Spam-Score: -12.30 On Fri, 06 Nov 2026 19:39:53 +0100, Sreeraj S Kurup wrote: > > mode_store() updates led->mode while holding > snd_ctl_led_mutex. > > However, snd_ctl_led_set_state() and mode_show() read this > field without holding the same mutex. > > This can cause a data race when userspace changes the mode > while another path reads it. > > Read the mode under snd_ctl_led_mutex in > snd_ctl_led_set_state() and use the local value after > releasing the mutex. > > Also protect the mode read in mode_show() with the mutex. > > Fixes: cb17fe0045aa ("ALSA: control - add sysfs support to the LED trigger module") > Signed-off-by: Sreeraj S Kurup As this sort of data race for a single value has no much impact on the actual behavior, it's more or less just for consistency. So I applied to for-next branch. Thanks. Takashi