From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout-p-201.mailbox.org (mout-p-201.mailbox.org [80.241.56.171]) (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 23003303A35; Wed, 11 Feb 2026 19:18:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770837482; cv=none; b=oVxUJ7/+OVVhVnW8IjxPLtdevKGSE+uXsM96DVM33wcNEY4rTN3K8FCXVblj5+8s/RaXzBLeZSN+sfvaJ9Ih0aNIAAnHdwMExbmydeVJQJxKB+35fVvCt1GRrURYpnasogSN69LtT7WmUlwj7FiqLVvf+xZCfEd/fb3NTffTB7Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770837482; c=relaxed/simple; bh=lDh8dX0kpuo2VFAo5YwZs9ID0zMqXXMty5OMGfVSOaY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Ep2OKiB4Ivk6iW/M2mlhi6Jj9XlhFRZucrHBz4qwvVqWF3s5jcGLBla6Jo5PFQl0GWI+8tEVQIyXwt5iwPKVQsiKRukCA/mgBmjNUHLbR3DIEA4zOBwQUyAXeQ7k6ToMbbs4We5H5xTBImbLvTFnxiMNxUwfvBiRNQmXk/VP6ck= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org; spf=pass smtp.mailfrom=mailbox.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b=N5y4TIAj; arc=none smtp.client-ip=80.241.56.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mailbox.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b="N5y4TIAj" Received: from smtp202.mailbox.org (smtp202.mailbox.org [IPv6:2001:67c:2050:b231:465::202]) (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 mout-p-201.mailbox.org (Postfix) with ESMTPS id 4fB7Vs2h8Zz9vBY; Wed, 11 Feb 2026 20:17:57 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mailbox.org; s=mail20150812; t=1770837477; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=p5M1b+oSA0YS4SriAeQJke7xSD+ujiJ75qVTi/6MjTI=; b=N5y4TIAjyvdzKisa1jI3YmkiMgSMkt30boCG7jtAgt3N6CtAAoanhTl2BG3lT3e9qjMjBW 7geMYHLA6SAaS3RddyGOhcE5YubSEUSFdw3FHDJ1bddtWGYwiUmYD3i5uixltsxtci5pSA TYRQeb8kG40qtVRKRXTNmU+BjEa7HEcLXVQxauHywLkZvnwy5BW1wNltIGkaTFrnLG/Q/U MFf1Vk1GGNGTyJQqwYjeuycfBO/oZElO0OtyqPOu7Hge4nBk9QlFGC2rwX9k02OCnkhN6P ZOJVw/qYtI4yEIVPI9cKNwQAPD1fFYxfAMdAzMRi314NaUTwkceKMj4P5Ny0UA== Message-ID: Date: Wed, 11 Feb 2026 20:17:52 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH] drm/imagination: Convert to dev_pm_domain_{at,de}tach_list() To: Geert Uytterhoeven , Matt Coster , Thorsten Leemhuis Cc: Frank Binns , Brajesh Gupta , Alessio Belle , Alexandru Dadu , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , "dri-devel@lists.freedesktop.org" , "linux-pm@vger.kernel.org" , "linux-renesas-soc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Linux regressions mailing list References: <194465eda54d1f852a9226cf691ddc5aa208e0a3.1769097977.git.geert+renesas@glider.be> Content-Language: en-US From: Marek Vasut In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-MBO-RS-META: hfo1ysp6dxn384tk37dfppkcoc1of6be X-MBO-RS-ID: c00b551ddfadc58db55 On 1/23/26 2:50 PM, Geert Uytterhoeven wrote: Hello everyone, > On Fri, 23 Jan 2026 at 14:36, Matt Coster wrote: >> On 22/01/2026 16:08, Geert Uytterhoeven wrote: >>> Call the dev_pm_domain_attach_list() and dev_pm_domain_detach_list() >>> helpers instead of open-coding multi PM Domain handling. >>> >>> This changes behavior slightly: >>> - The new handling is also applied in case of a single PM Domain, >>> - PM Domains are now referred to by index instead of by name, but >>> "make dtbs_check" enforces the actual naming and ordering anyway, >>> - There are no longer device links created between virtual domain >>> devices, only between virtual devices and the parent device. >> >> We still need this guarantee, both at start and end of day. In the >> current implementation dev_pm_domain_attach_list() iterates forwards, >> but so does dev_pm_domain_detach_list(). Even if we changed that, I'd >> prefer not to rely on the implementation details when we can declare the >> dependencies explicitly. > > Note that on R-Car, the PM Domains are nested (see e.g. r8a7795_areas[]), > so they are always (un)powered in the correct order. But that may not > be the case in the integration on other SoCs. > >> We had/have a patch (attached) kicking around internally to use the >> *_list() functions but keep the inter-domain links in place; it got held >> up by discussions as to whether we actually need those dependencies for >> the hardware to behave correctly. Your patch spurred me to run around >> the office and nag people a bit, and it seems we really do need to care >> about the ordering. > > OK. > >> Can you add the links back in for a V2 or I can properly send the >> attached patch instead, I don't mind either way. > > Please move forward with your patch, you are the expert. > I prefer not to be blamed for any breakage ;-) Has there been any progress on fixing this kernel crash ? There are already two proposed solutions, but no fix is upstream. -- Best regards, Marek Vasut