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 83252270552 for ; Fri, 25 Sep 2026 02:31:16 +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=1790303477; cv=none; b=W7GdzEqNx3LYKUChvlvGMuEaVvfsrcHWPL9juMLYbQq5ftDQu5/muEGIULRVduEWyRRIVOdQ2xXdLJqsQWEdIZDV25Fvv4wFbExknVwdH33ITtWyVXxFsKY/0T/j55wSoBVYt96NULP5aK3ZdbCluFQi/1zpe+1ijAscYuZFs+w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790303477; c=relaxed/simple; bh=fUZRymZ7Skzg07w0oS+sIcXWjOo7C2Cp7zlQ4WCnEgw=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=adGtDgsOngIHD9/0iPgho4hu7cP2bL8Eq+PguJFkCga7n7bY3lATqseoqlhHxhsvFIlRlRbpbZB8sgYfUJ8BwgICrmBvJLxRNsQNB5Cq6UxXLwgOyAPB6tx+TAQG8xAPeSSBrrmz4HPx1gGFoJGhcbvuL34HuL/B2wQFHHXW6p4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JZAgeDmi; 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="JZAgeDmi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0C6971F000FF; Fri, 25 Sep 2026 02:31:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790303476; bh=fUZRymZ7Skzg07w0oS+sIcXWjOo7C2Cp7zlQ4WCnEgw=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=JZAgeDmihBd1AQFRjxoZ6yBaZUHB/PtLLpoOROXbl2Q6REJRmeuO1a2Ss5ijUvtjF tcFrn6mHf6tLdH4lddeYijosAwvZO8yUUHntItO59MH/8h645rZ5OCzUjyGwfJaEWR XSk1dmacGGrqZ4yW/Veck3nfSC7x6WORXxk304uPZ87fUp9U6MLFlBE2DvyAXzmiE1 Jy+3/wEIWIfCbQQbqn3vVdx3fZ5sDp/aLtdAbxnPxv1P38YZlKC1CEEK+tvArA4koW c20mBwh3GjEyTex+zDHWCaBdX5rlAMFteLh8WswYZkoztRAHBxvqdPSpH6F5RIqKjs JIXUbZbBwGCUA== From: sashiko-bot@kernel.org Subject: Re: [PATCH 3/3] hwmon: (coretemp) Add temp%d_fault sysfs attribute Reply-To: sashiko-reviews@lists.linux.dev To: "Ricardo Neri" Cc: linux-hwmon@vger.kernel.org In-Reply-To: <20260924-coretemp-temp-fault-v1-3-1884f0ff97d5@linux.intel.com> References: <20260924-coretemp-temp-fault-v1-0-1884f0ff97d5@linux.intel.com> <20260924-coretemp-temp-fault-v1-3-1884f0ff97d5@linux.intel.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 25 Sep 2026 02:31:15 +0000 Message-Id: <20260925023116.0C6971F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-hwmon@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > The temp%d_input sysfs attribute reports the CPU core temperature > regardless of the valid bit (bit 31) in IA32_[PACKAGE]_THERM_STATUS. > Commit bf6ea084ebb5 ("hwmon: (coretemp) Do not return -EAGAIN for low > temperatures") established this behavior after observing that some Intel > CPUs do not set the valid bit while the temperature is too low to be > measured. The value reported is of more use than an error. Changing this = is > not an option: the interface is long-established and userspace relies on > it never failing. >=20 > Userspace, however, cannot distinguish a genuinely low temperature from > one the CPU could not measure. Until that commit it could: reading > temp%d_input returned -EAGAIN. That signal was removed and nothing > replaced it. Report the inverse of the valid bit through the standard hwm= on > temp%d_fault attribute. Its documented meaning is that the measurement > for that channel should not be trusted. Tools built on libsensors consume > the standard attribute. >=20 > temp%d_input continues to ignore the valid bit. A new update_temp() helper > refreshes the cached temperature and its fault state together, so both > attributes are served from the same reading of the status register. >=20 > Signed-off-by: Ricardo Neri Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260924-coretemp-t= emp-fault-v1-0-1884f0ff97d5@linux.intel.com?part=3D3