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 2C2EF3BCD33 for ; Fri, 3 Jul 2026 11:16:12 +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=1783077374; cv=none; b=UJuJ+zolQfQzcom4h5B/swJpKq4CaQhYM/7ZrWV+LrpI709lu7gbuMAzrPur37CSvBUFvV7spYrnr7iXxWX2tQKfN3CuSxD5UZCcCEs37z1a35bRMr4GHRim1uPCJfdEjlqX2Jm7oPKhwNUzPTRyu93jBH+INTZ7HCGcu+lKptc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783077374; c=relaxed/simple; bh=qR8Z8mfcCWpOhOHlVB6udkXseW1bEhKnL/HnKmin5Yo=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=Q+QTigpvYCEwzhfEcbrsBEILfVaaG4n96igCXeGbFr6apCJId/rYwWi8KxyGNn5NWo+kZwHbXbm2driu8z5LPFzHHBKw1+yMikAsC8h5amR7U3ZWMEMQhyZIjSgG6Xfeh55MPGUNeKruSXQtrLKM9lG+iaWDmpRwkTwgBf/HV7M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=V5zJaOBS; 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="V5zJaOBS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EA471F000E9; Fri, 3 Jul 2026 11:16:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783077372; bh=sWQ5ukA7crvN7Xofjd6i1sjzuHAF/KO53nOPnpW5xK8=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=V5zJaOBS2uKhFE2vLGkpUgFy45CyJsYRtslnLCj7MOjpax4l23ANyD8x9quOxRI/s i3kFIflq76jHh4PMBsyVOrqqJtMtNe4PCqcq88VoSvcd/nB0a1rS2ISIQuXVLhbcb+ MLqjNL8GLjWDAj8gIDPnVglifK47Cz1MTaJ76q+vf0xPMMpYdS0/kQuC+C2oxad1kg +5Pqj/gxP2y2vaXa8IZ/T3CW56Fm1TuZquitxP7RSeDsCFMIRqT5xYT+JaQcAtwkQP pbA6+bcG9l6RRVkWe2kUiOhWrZBaou3fhJW5iNfVxpdQVDngY3gQTsc7tGFuhBu2XS ZoXwu8JrtDV4Q== From: sashiko-bot@kernel.org Subject: Re: [PATCH v3 03/13] power: sequencing: Add pwrseq_power_is_on() Reply-To: sashiko-reviews@lists.linux.dev To: "Chen-Yu Tsai" Cc: conor+dt@kernel.org, robh@kernel.org, devicetree@vger.kernel.org In-Reply-To: <20260703110317.1283411-4-wenst@chromium.org> References: <20260703110317.1283411-1-wenst@chromium.org> <20260703110317.1283411-4-wenst@chromium.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 03 Jul 2026 11:16:11 +0000 Message-Id: <20260703111612.5EA471F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Thank you for your contribution! Sashiko AI review found 3 potential issue(= s) to consider: - [Medium] pwrseq_power_is_on() returns -EINVAL for a NULL descriptor, whic= h evaluates to true in a boolean context and breaks the optional resource p= attern. - [Low] The patch forgets to add the dummy implementation of pwrseq_power_i= s_on() for when CONFIG_POWER_SEQUENCING is disabled. - [Low] Lockless read of desc->powered_on introduces a data race. -- commit c1fd36a14061ff4c3c20d9f5699bb342ce2b052d Author: Chen-Yu Tsai power: sequencing: Add pwrseq_power_is_on() The power sequencing consumer API already does power on state tracking internally. Expose the state to consumers through pwrseq_power_is_on() so that they don't have to reimplement it locally. > diff --git a/drivers/power/sequencing/core.c b/drivers/power/sequencing/c= ore.c > index 02f42da915985..72b96d36920e5 100644 > --- a/drivers/power/sequencing/core.c > +++ b/drivers/power/sequencing/core.c > @@ -968,6 +968,24 @@ int pwrseq_power_off(struct pwrseq_desc *desc) > } > EXPORT_SYMBOL_GPL(pwrseq_power_off); > =20 > +/** > + * pwrseq_power_is_on() - Queries the last requested state of the power = sequencer. > + * @desc: Descriptor referencing the power sequencer. > + * > + * This returns the last requested state of the power sequencer. > + * > + * Returns: > + * On success, 1 for on and 0 for off; negative error number on failure. > + */ > +int pwrseq_power_is_on(struct pwrseq_desc *desc) > +{ > + if (!desc) > + return -EINVAL; [Severity: Medium] Since pwrseq_power_on() gracefully handles an optional sequencer by returning 0 when desc is NULL, should pwrseq_power_is_on() also handle a NU= LL descriptor without returning an error? Because -EINVAL is non-zero, returning it for a NULL descriptor will evaluate to true in a boolean context. Consumers querying the state of an optional sequencer using if (pwrseq_power_is_on(desc)) could falsely evaluate this as powered on. > + > + return desc->powered_on; [Severity: Low] Is it safe to read desc->powered_on locklessly here? Because desc->powered_on is mutated dynamically by pwrseq_power_on() and pwrseq_power_off() under pwrseq->state_lock, concurrent calls to pwrseq_power_is_on() could result in a data race. Could this read use READ_ONCE() (along with WRITE_ONCE() during updates) or be protected by the state_lock? > +} > +EXPORT_SYMBOL_GPL(pwrseq_power_is_on); > + > /** > * pwrseq_to_device() - Get the pwrseq device pointer from a descriptor. > * @desc: Descriptor referencing the power sequencer. [ ... ] > diff --git a/include/linux/pwrseq/consumer.h b/include/linux/pwrseq/consu= mer.h > index 3c907c9e1885d..5a5eaf85d5db9 100644 > --- a/include/linux/pwrseq/consumer.h > +++ b/include/linux/pwrseq/consumer.h > @@ -22,6 +22,7 @@ devm_pwrseq_get(struct device *dev, const char *target); > =20 > int pwrseq_power_on(struct pwrseq_desc *desc); > int pwrseq_power_off(struct pwrseq_desc *desc); > +int pwrseq_power_is_on(struct pwrseq_desc *desc); > =20 > struct device *pwrseq_to_device(struct pwrseq_desc *desc); [ ... ] > #else /* CONFIG_POWER_SEQUENCING */ [ ... ] > static inline int pwrseq_power_on(struct pwrseq_desc *desc) > { > return -ENOSYS; > } > =20 > static inline int pwrseq_power_off(struct pwrseq_desc *desc) > { > return -ENOSYS; > } > =20 > static inline struct device *pwrseq_to_device(struct pwrseq_desc *desc) > { > return NULL; > } > =20 > #endif /* CONFIG_POWER_SEQUENCING */ [Severity: Low] Does this patch miss a dummy implementation of pwrseq_power_is_on() for when CONFIG_POWER_SEQUENCING is disabled? Any consumer driver using this function when the config is disabled will cause a build failure due to an undeclared function. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260703110317.1283= 411-1-wenst@chromium.org?part=3D3