From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 4FD9533710B; Fri, 17 Oct 2025 15:09:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760713784; cv=none; b=RkJ2n8vtR3QGMa9IKG2xubp5jHRC10RRrq28zn4OBS8EF83aXrM7U4hqM+cxoFJbo1mZYkGPUfm/bQQoL855OA7Ut0Mp563iZc2ldGhDu1Q3nalEDl2vvYitRCnrSheTG8gaZij6Sank/CtfpVwOirtHa4wDu8ByERJ3jAYZJ+E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760713784; c=relaxed/simple; bh=5kFpIzrHfJwSGVCn8pMoqqufQn1zu1A/9cf4NPs8i7M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GDJceRuuXQbZkG8iuJm59srpZMhEgOPJtX/jSoTD3Svv4/9uHvNeNPIE6gPTtVeMN0JlhjWDUDZoUi6mfDIwxek/JoWkSn428J1Ys4q1/XyQ4Hi9CzQhDYRJHjmppfny+AaRW1Y3AUbBNHTTcIVdh0/TytNp9CSwRlMza6492Kw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=F0R2RNuv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="F0R2RNuv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 62125C4CEE7; Fri, 17 Oct 2025 15:09:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1760713783; bh=5kFpIzrHfJwSGVCn8pMoqqufQn1zu1A/9cf4NPs8i7M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=F0R2RNuvkQ3FFHmY8lTjw35ngIz3X1nDNg4O+EyoQUP25Te8y+9ZAx841Qy39Q1ww +4OqQzsju0GkCmDozlh2Ngsls6mE3umlEqr1FZyMkhO3kGoOUpUe6jL6f7JV7y5gIy iAGbpN1P0L0XNd4Rwsjk/z/rqYvl7QRGw4JLjtBY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Rafael J. Wysocki" , Zihuan Zhang Subject: [PATCH 6.6 085/201] cpufreq: intel_pstate: Fix object lifecycle issue in update_qos_request() Date: Fri, 17 Oct 2025 16:52:26 +0200 Message-ID: <20251017145137.877950081@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251017145134.710337454@linuxfoundation.org> References: <20251017145134.710337454@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rafael J. Wysocki commit 69e5d50fcf4093fb3f9f41c4f931f12c2ca8c467 upstream. The cpufreq_cpu_put() call in update_qos_request() takes place too early because the latter subsequently calls freq_qos_update_request() that indirectly accesses the policy object in question through the QoS request object passed to it. Fortunately, update_qos_request() is called under intel_pstate_driver_lock, so this issue does not matter for changing the intel_pstate operation mode, but it theoretically can cause a crash to occur on CPU device hot removal (which currently can only happen in virt, but it is formally supported nevertheless). Address this issue by modifying update_qos_request() to drop the reference to the policy later. Fixes: da5c504c7aae ("cpufreq: intel_pstate: Implement QoS supported freq constraints") Cc: 5.4+ # 5.4+ Signed-off-by: Rafael J. Wysocki Reviewed-by: Zihuan Zhang Link: https://patch.msgid.link/2255671.irdbgypaU6@rafael.j.wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/cpufreq/intel_pstate.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -1341,10 +1341,10 @@ static void update_qos_request(enum freq continue; req = policy->driver_data; - cpufreq_cpu_put(policy); - - if (!req) + if (!req) { + cpufreq_cpu_put(policy); continue; + } if (hwp_active) intel_pstate_get_hwp_cap(cpu); @@ -1360,6 +1360,8 @@ static void update_qos_request(enum freq if (freq_qos_update_request(req, freq) < 0) pr_warn("Failed to update freq constraint: CPU%d\n", i); + + cpufreq_cpu_put(policy); } }