From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794065084; b=R4ZMFyFv4P54ZAYzbsDiLpRHUbPzwAl417iba7g3rMdFv64/GMJGL2hcdeSHm/GXIhq+ XSBrW02+Q165iw6wgJFoYS5ovuwalqz0vgvhZQI9zWb2raf8RzSgsdvHnkUB8oLS1IPro 5UXwawS18SBhAMLUAjb2ApcvCXghJpYKBx1OYtVTllYcSiHlFg4FjETqXq8EBHT8vJD88 da+UHHC8LN83687RbdM1RwTrXamVdBXWdopnECs80syMjQb63Lp+kpGg4cKKa5GDE+Mz0 dZTi779XyJ//jche5Vdv5jmZ8/rDcamtjHsYPweWJ4XE5H9VPx2FeoCJFwBlWpSfJ4Q== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794065084; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=gG9fQdpJtmYJQFqWX+RuCkogPI8mm+gW+Nl8BBtI+3o=; b=KYYjNJI9SwVI+UNQ7iMlx7EtfGSgopvMe8v7yqBsG77/1kxj8Ju/7c/Kdzs3pe2gNQRY Sfscc1FD/ikFTLzZ3iBWUVcrqmjME0nbQBN/HJblSpT3SwZdIVOJZE2YWZlT+6Me7tKkc eYoUkwv/r3CwHZo+ke9Mwo9D5TBWLs5f2qolVc+AR8SJ4uZinTauhUb3aqPwfxCBY/Rrs GwS+eNfiPO1UH2s1z5sVTV5GHk+oI4LIN73mrCkjzYdnXsRFzdo8y0z2XQ/MvLeqD2U0Q gtzyUVakxMJVuVzhxP5D8NZtArE+kq+XkLR8tj8OZygHX567sgR2zLxqzkyMOJgoHKQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=pTpIVu2V; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 215F5606A326; Sat, 7 Nov 2026 15:24:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=pTpIVu2V Received: by smtp.kernel.org (Postfix) with ESMTPSA id C20831F0089F; Sat, 7 Nov 2026 15:24:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794065084; bh=gG9fQdpJtmYJQFqWX+RuCkogPI8mm+gW+Nl8BBtI+3o=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=pTpIVu2VPsqQoNMbgUd+p0a+ETzneAKjim8XdQ6kxxUJzEBssLZDdVlzXrJYilaMs MAP06yBHYFA30V0F/ThjF4vgoWr+fLmegQ2u8uaAh1cce8HTbszP9Uv8Opcn6OqhjT eCxpFgX5Joe4ByLw2sa41aGLF/SKeGILvlqCgWvI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Marcelo Tosatti , Ximing Zhang , =?UTF-8?q?Asaf=20Nuri=20Bertizlio=C4=9Flu?= , Guenter Roeck , Sasha Levin Subject: [PATCH 7.3 0880/1257] hwmon: (coretemp) Fix handling of isolated SMT siblings Date: Sat, 7 Nov 2026 08:52:56 -0500 Message-ID: <20261107135003.630328573@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134939.434104957@linuxfoundation.org> References: <20261107134939.434104957@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ximing Zhang [ Upstream commit 37c1974a0ec4ec4624a270291a179c53f8f4fbca ] Commit 0f8b916bc5b5 ("hwmon: (coretemp) avoid RDMSR interrupts to isolated CPUs") prevents create_core_data() from creating temperature data for an isolated CPU. coretemp_cpu_online(), however, still adds that CPU to pdata->cpumask. When an isolated SMT thread is processed before a housekeeping sibling, the mask makes coretemp_cpu_online() believe that the core is already represented. The housekeeping sibling then gets no temperature attributes. Package attributes are similarly not retried when the first CPU processed in a die is isolated. The mask is also used to select a replacement CPU when a sensor target goes offline. Including isolated CPUs permits the driver to retarget a sensor to one, causing subsequent sysfs reads to send an RDMSR IPI to an isolated CPU. Keep isolated CPUs out of pdata->cpumask by moving the housekeeping check to coretemp_cpu_online(). Sensor creation is then deferred to an eligible CPU, and hotplug replacement targets remain on housekeeping CPUs. Tested on an Intel Core i7-10510U running 6.18.50-3-cachyos-lts, with nohz_full=1 on CPU 1 and its housekeeping SMT sibling on CPU 5. The stock driver omitted Core 1 after module load and retained its readable sensor after CPU 5 was offlined. The patched driver exposed Core 1, removed it when CPU 5 went offline, and restored it when CPU 5 returned. Fixes: 0f8b916bc5b5 ("hwmon: (coretemp) avoid RDMSR interrupts to isolated CPUs") Cc: stable@vger.kernel.org Cc: Marcelo Tosatti Signed-off-by: Ximing Zhang Tested-by: Asaf Nuri Bertizlioğlu Link: https://patch.msgid.link/20261016-codex-coretemp-housekeeping-v1-1-96618c5676b2@gmail.com Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/coretemp.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c index bee2c9896d4c5..9ed21c8c093a5 100644 --- a/drivers/hwmon/coretemp.c +++ b/drivers/hwmon/coretemp.c @@ -568,9 +568,6 @@ static int create_core_data(struct platform_device *pdev, unsigned int cpu, u64 val; int err; - if (!housekeeping_cpu(cpu, HK_TYPE_MISC)) - return 0; - tdata = init_temp_data(pdata, cpu, pkg_flag); if (!tdata) return -ENOMEM; @@ -690,6 +687,14 @@ static int coretemp_cpu_online(unsigned int cpu) if (!cpu_has(c, X86_FEATURE_DTHERM)) return -ENODEV; + /* + * Keep isolated CPUs out of pdata->cpumask. Besides tracking the CPUs + * available to this driver, the mask is used to select the CPU on which + * to read the temperature MSRs. + */ + if (!housekeeping_cpu(cpu, HK_TYPE_MISC)) + return 0; + pdata = platform_get_drvdata(pdev); if (!pdata->hwmon_dev) { struct device *hwmon; @@ -719,8 +724,8 @@ static int coretemp_cpu_online(unsigned int cpu) } /* - * Check whether a thread sibling is already online. If not add the - * interface for this CPU core. + * Check whether a housekeeping thread sibling is already online. If + * not, add the interface for this CPU core. */ if (!cpumask_intersects(&pdata->cpumask, topology_sibling_cpumask(cpu))) coretemp_add_core(pdev, cpu, 0); @@ -750,9 +755,9 @@ static int coretemp_cpu_offline(unsigned int cpu) cpumask_clear_cpu(cpu, &pd->cpumask); /* - * If this is the last thread sibling, remove the CPU core - * interface, If there is still a sibling online, transfer the - * target cpu of that core interface to it. + * If this is the last housekeeping thread sibling, remove the CPU core + * interface. If there is still a housekeeping sibling online, transfer + * the target CPU of that core interface to it. */ target = cpumask_any_and(&pd->cpumask, topology_sibling_cpumask(cpu)); if (target >= nr_cpu_ids) { @@ -764,7 +769,8 @@ static int coretemp_cpu_offline(unsigned int cpu) } /* - * If all cores in this pkg are offline, remove the interface. + * If all housekeeping cores in this pkg are offline, remove the + * interface. */ tdata = get_temp_data(pd, -1); if (cpumask_empty(&pd->cpumask)) { @@ -777,7 +783,7 @@ static int coretemp_cpu_offline(unsigned int cpu) /* * Check whether this core is the target for the package - * interface. We need to assign it to some other cpu. + * interface. We need to assign it to some other housekeeping CPU. */ if (tdata && tdata->cpu == cpu) { target = cpumask_first(&pd->cpumask); -- 2.53.0