From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout.web.de (mout.web.de [212.227.15.14]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 180743211; Sat, 20 Jul 2024 15:14:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=212.227.15.14 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721488465; cv=none; b=NCsyN0M2XKKP6sfYlDpfIiU/lE5YABSyInDpSir8Ckcou3g8WLjnzMzOVyS2Es1CApKwqoMoJrrzMmHhZ+pwNCGIJyFAl1ksl5obsRpwQbbBh+mkG4LObfl61ZZMNk/M2HdPP2gnpH/DavFPrTKYZ21CiqK8SpoK49I/3Vpoc3w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721488465; c=relaxed/simple; bh=5pzifyv6T9S3l5lxU+v2lCCh2MU1upZk0O9VOXNqQ2A=; h=Message-ID:Date:MIME-Version:To:Cc:References:Subject:From: In-Reply-To:Content-Type; b=mYtlZ//vA+FS/07Vz6rj/VudSo94yQvtAJIcByQIpu45HmJ5qi+fKznbs1gv7e7CZxZ+13KVJgewYflZB7guSjSn5gCulTGPtxMAZhrMlkwCAoKTMmQ+Xt7btu9zx5HyFaryazKdJ6NAagIDxmuYch9CMk6ylA2BSsy8LMZWf/Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=web.de; spf=pass smtp.mailfrom=web.de; dkim=pass (2048-bit key) header.d=web.de header.i=markus.elfring@web.de header.b=niEuGOg7; arc=none smtp.client-ip=212.227.15.14 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=web.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=web.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=web.de header.i=markus.elfring@web.de header.b="niEuGOg7" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=web.de; s=s29768273; t=1721488426; x=1722093226; i=markus.elfring@web.de; bh=ANLLE1FZ2RR1WHzVhAMXGwQ0A90YNENVV09Nc6XgQhM=; h=X-UI-Sender-Class:Message-ID:Date:MIME-Version:To:Cc:References: Subject:From:In-Reply-To:Content-Type:Content-Transfer-Encoding: cc:content-transfer-encoding:content-type:date:from:message-id: mime-version:reply-to:subject:to; b=niEuGOg7Z67VcGebyFHv3zykSxYdZG1fY+7vLDdpz1JGW6r4YueAX1G33SyKt+Tc 83PGlnI5ZYSmAazeUUkGWWTJ6nlq6Z4TL2XC1qQJxRzG4rgpHmtIlw+VycNvf4gft k0aPq9W/9P9T5EhJqdG6+1VlFQnSWv/Dak6vV8HQJZ4+mCe02rHG9TYEa8ChaPmhO ads+Q7f/cvqQERJhd/TlTMppI/kbikZN/MrpRcGduAEYVyVJ6ok2UgvYIk1Dd+v5A a9O+1RsGm6UUHEOlRSHA36caPsiPca16KhpyqdQJo92cJJsbnnTDJIdluBLDC17/0 m3rM9rwiZXWbuK3xaw== X-UI-Sender-Class: 814a7b36-bfc1-4dae-8640-3722d8ec6cd6 Received: from [192.168.178.21] ([94.31.89.95]) by smtp.web.de (mrweb005 [213.165.67.108]) with ESMTPSA (Nemesis) id 1MK52w-1sl4lg1Eo2-00Y4JF; Sat, 20 Jul 2024 17:13:46 +0200 Message-ID: <2f5e5e81-21e1-421d-94ac-e4507b323680@web.de> Date: Sat, 20 Jul 2024 17:13:40 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: John Stultz , "T. J. Mercier" , Yong Wu , Yunfei Dong , Project_Global_Chrome_Upstream_Group@mediatek.com, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, Angelo Gioacchino Del Regno , Benjamin Gaignard , Hans Verkuil , Jeffrey Kardatzke , Marek Szyprowski , Mauro Carvalho Chehab , Nathan Hebert , Nicolas Dufresne , =?UTF-8?B?TsOtY29sYXMgRi4gUi4gQS4gUHJhZG8=?= , Sebastian Fricke , Tomasz Figa Cc: LKML , Brian Starkey , Chen-Yu Tsai , =?UTF-8?Q?Christian_K=C3=B6nig?= , Daniel Vetter , =?UTF-8?Q?Fritz_K=C3=B6nig?= , Hsin-yi Wang , Matthias Brugger , Steve Cho , Sumit Semwal References: <20240720071606.27930-6-yunfei.dong@mediatek.com> Subject: Re: [PATCH v7 05/28] dma-heap: Add proper kref handling on dma-buf heaps Content-Language: en-GB From: Markus Elfring In-Reply-To: <20240720071606.27930-6-yunfei.dong@mediatek.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:xCN5kVOJmi+99iZxV3ZaFC6z2tacIVcN87B7sFZUAIuVsvE+9jv va3LRkLSLMeceACmgBSFOUukvR38UNxFX/NlWYBwox7+fj26qbNooHxlk6pjhOuseQNeWnL /3+jMkhEj3ZKTq/IwIeY1nUIups/APFVOUGezCq2bLqs5N7p6eSG+gVqkMv/1p3PvzkCQFW Kw/AMe70ASauwualb0xxg== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:fcstDclSA/c=;Ctdm7nJtr8AasI7Q1uuh4tDtijF 9crG4aP1nI9tsA386U6h4nJ4nl+QyJ74s4jG208s6DMRxby79tk8cqJJMXDWAcgLgJY/zECSk r4+qULjryDobIvcd6U1fo70kUgJvuTM+U9CsyCsjt/X9sSfXQ/6FJtLVxH00s0+9BTyjdkPSg cVJVaUIXHWRHC6XMOYDSvqdoMBpcsfJWIEhcIwnn/8vAlCowZYitX3WH4+r21ha5tLMtaaZwm Ppd8g6ucZ8C9nLezzOXaGyb9Upy+Q7UIsGHq38JmxfM9N563opDD+HC558mkAf3QSwQVV2qWe Fg/SlTkdK6g+r1WIQvy78XKG2rp/SvJ4gofIxzvryrB4Chl5g4I9xg0I+q+x4a/2GMy9nV5Dl 02+KmWYHGZA40OYYXhamroFBYKM9a2ibSAHI1b0+LJXs3AkaN3zbdZSSRvhGosBQ7y98S12Fq UMYWAiEhZtFfBCB4E020p1zDd3ye46noeNeNvWAT67NLDcjW/o8njm7XgaNipa/S69N6y2Hoc ep8QAGXO62ZFkUw4ndT65ch9qt2nfnVzP14T+V9eC8zVw2Nm0qGT1duSpiT8aPGwHHVGbEbue MzbvlaC8+GEFmeE3Nz6Vb9yeFrI0kAgHMNjis3L5SBxn99Fp9h1Ot0AAVARbH1AIXW7TNibDs 8RIjviyBlUwBbu2uBGfyxqzBdtU0tjF3xL+pDimUQkFD4EyzH1j143hboMXSWwIDPQ0CP5k0E pVK5CEoEoLmbKrIeqbpK6qsfNKsZ+kCDxKOIRpG98ucqt+TibYt5xyc/NDINRVvEockjhnhQ3 hPxiYz5X+aASwg/7ShR7ehMA== =E2=80=A6 > +++ b/drivers/dma-buf/dma-heap.c =E2=80=A6 > +static void dma_heap_release(struct kref *ref) > +{ =E2=80=A6 > + mutex_lock(&heap_list_lock); > + list_del(&heap->list); > + mutex_unlock(&heap_list_lock); =E2=80=A6 Under which circumstances would you become interested to apply a statement like =E2=80=9Cguard(mutex)(&heap_list_lock);=E2=80=9D? https://elixir.bootlin.com/linux/v6.10/source/include/linux/mutex.h#L196 Regards, Markus