From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 3B3C93EEAE9 for ; Wed, 2 Sep 2026 19:44:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788378302; cv=none; b=ZNJYnCr450afHMcJPrDjhx6Fw2EQFXrOE2nkEAodEjJeEwkOwg8dK0vef5R8Yc9i9vdoQu/zIz24nbXbKoChEzMXMR562NSU1c09pb9fJtit7R2swRt+lNAD/w2Qnr6z86yDWvmQjQ3cnjjbfuJIrVO9XMeBmlg5eSlsJ29PI4s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788378302; c=relaxed/simple; bh=1xlRM1APFNd4cG8kZlm1fEDE0nCXG6R0HVSS1UpD9BE=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=XDSjXnC4/vY3kqgwmItGVtXsoo2M8+dTbXJQIXwFdXjclo79osVLva9I1lMenwzpzRwEz9PH1NCs+ruxRAVowx0A9BvbO6FAHaayNK95z6f8YGiHQRHNn4l6uEJHQMUsF1bBQLV5fArO9ojpsFuuzPVN0MGBfKXwDHr7PAE82ic= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ML5FQsWZ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ML5FQsWZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE6951F00A3A; Wed, 2 Sep 2026 19:44:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788378280; bh=FQ59A4b36CmQ3qk1zJntjqbygdyZBGI3CJ0IL+snHxk=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=ML5FQsWZvK6L/qeRFNNyEf7RhY3XI5gEafi9szzlOrhWMleQTN/buzcNqNy3apYvY Qj515xIVQgWid/64sFPdoV0GL0MQ3QGnmp7p5nwuYDs6qcUDN59sYr1eDET8Arc4Ql k6hEpbycdhWMVL0gVJA0qqzffD18NKorPW3lyfDiiHTX7vu69qdjD4fzzcOummbhI+ sq6ZC8RBp59zyWEtYkAcnGNZE1lew/zimXsFXTczsvMpt5CDQ5n3ZQSSBylT0kXVtJ AwtfwTMk7iULA5gMEG4ys1hfdK5QiaZj5Cge4c3Um/oTe1SyVfD5y0mMi5tmMGtUQd RhjMqtvYAjIPg== From: sashiko-bot@kernel.org Subject: Re: [PATCH v2 1/6] ACPI: PM: Drop parent state update from acpi_device_get_power() Reply-To: sashiko-reviews@lists.linux.dev To: "Rafael J. Wysocki" Cc: linux-pci@vger.kernel.org In-Reply-To: <2292173.irdbgypaU6@rafael.j.wysocki> References: <5144065.31r3eYUQgx@rafael.j.wysocki> <2292173.irdbgypaU6@rafael.j.wysocki> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 02 Sep 2026 19:44:39 +0000 Message-Id: <20260902194439.DE6951F00A3A@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > From: "Rafael J. Wysocki" >=20 > The parent state update in acpi_device_get_power(), that occurs when the > child device turns out to be in D0 and the parent's power state is still > unknown, is highly questionable because it may cause the reference > counters of the power resources used by the parent in D0 (if any) to > underflow when the parent goes into a low-power state later. Moreover, > there is no reason to do it on reads from the real_power_state sysfs > attribute of the child. >=20 > That check had been added by commit 8f7412a792bc ("ACPI / PM: Infer > parent power state from child if unknown, v2") before starting to > handle the "missing _PSC and no power resources" case directly in > acpi_bus_init_power(), as of commit b3785492268f ("ACPI / PM: Do not > power manage devices in unknown initial states"). It is not necessary > any more and commit b3785492268f should have removed it. >=20 > Drop it now. >=20 > Fixes: b3785492268f ("ACPI / PM: Do not power manage devices in unknown i= nitial states") > Signed-off-by: Rafael J. Wysocki Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/5144065.31r3eYUQgx@= rafael.j.wysocki?part=3D1