From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 814B3C433EF for ; Tue, 16 Nov 2021 01:19:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 651D363255 for ; Tue, 16 Nov 2021 01:19:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346334AbhKPBWN (ORCPT ); Mon, 15 Nov 2021 20:22:13 -0500 Received: from mail.kernel.org ([198.145.29.99]:44648 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244819AbhKOTRh (ORCPT ); Mon, 15 Nov 2021 14:17:37 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 42AF963422; Mon, 15 Nov 2021 18:24:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637000647; bh=QGEflUG12v/gP+3OoDI76Jyk3WtgoCdVPYNhXAHYJu8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mTjARGsX8xAajzkZ9M+aB6X0MAHbspjp452u+f0QjQfbh9a68Kczhgq7A3EaecVrB jH4+dqzJ7efQGxuP1HXQeR6EY2eNU37yelllFFSiGQWx4hcUHrcaL5KdalrpWqfTBV I7Oj6doYJ1Tg/NHGvcdnQ5a2nIcbxVthxXLL3QQc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julia Lawall , "Rafael J. Wysocki" , Sasha Levin Subject: [PATCH 5.14 737/849] cpufreq: intel_pstate: Clear HWP desired on suspend/shutdown and offline Date: Mon, 15 Nov 2021 18:03:40 +0100 Message-Id: <20211115165445.176039655@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165419.961798833@linuxfoundation.org> References: <20211115165419.961798833@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rafael J. Wysocki [ Upstream commit dbea75fe18f60e364de6d994fc938a24ba249d81 ] Commit a365ab6b9dfb ("cpufreq: intel_pstate: Implement the ->adjust_perf() callback") caused intel_pstate to use nonzero HWP desired values in certain usage scenarios, but it did not prevent them from being leaked into the confugirations in which HWP desired is expected to be 0. The failing scenarios are switching the driver from the passive mode to the active mode and starting a new kernel via kexec() while intel_pstate is running in the passive mode. To address this issue, ensure that HWP desired will be cleared on offline and suspend/shutdown. Fixes: a365ab6b9dfb ("cpufreq: intel_pstate: Implement the ->adjust_perf() callback") Reported-by: Julia Lawall Tested-by: Julia Lawall Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/cpufreq/intel_pstate.c | 32 ++++++++++++++++++++++++++++++-- 1 file changed, 30 insertions(+), 2 deletions(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 2789cad7403d8..9c56c209aac18 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -1076,9 +1076,16 @@ static void intel_pstate_hwp_offline(struct cpudata *cpu) */ value &= ~GENMASK_ULL(31, 24); value |= HWP_ENERGY_PERF_PREFERENCE(cpu->epp_cached); - WRITE_ONCE(cpu->hwp_req_cached, value); } + /* + * Clear the desired perf field in the cached HWP request value to + * prevent nonzero desired values from being leaked into the active + * mode. + */ + value &= ~HWP_DESIRED_PERF(~0L); + WRITE_ONCE(cpu->hwp_req_cached, value); + value &= ~GENMASK_ULL(31, 0); min_perf = HWP_LOWEST_PERF(READ_ONCE(cpu->hwp_cap_cached)); @@ -2947,6 +2954,27 @@ static int intel_cpufreq_cpu_exit(struct cpufreq_policy *policy) return intel_pstate_cpu_exit(policy); } +static int intel_cpufreq_suspend(struct cpufreq_policy *policy) +{ + intel_pstate_suspend(policy); + + if (hwp_active) { + struct cpudata *cpu = all_cpu_data[policy->cpu]; + u64 value = READ_ONCE(cpu->hwp_req_cached); + + /* + * Clear the desired perf field in MSR_HWP_REQUEST in case + * intel_cpufreq_adjust_perf() is in use and the last value + * written by it may not be suitable. + */ + value &= ~HWP_DESIRED_PERF(~0L); + wrmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, value); + WRITE_ONCE(cpu->hwp_req_cached, value); + } + + return 0; +} + static struct cpufreq_driver intel_cpufreq = { .flags = CPUFREQ_CONST_LOOPS, .verify = intel_cpufreq_verify_policy, @@ -2956,7 +2984,7 @@ static struct cpufreq_driver intel_cpufreq = { .exit = intel_cpufreq_cpu_exit, .offline = intel_cpufreq_cpu_offline, .online = intel_pstate_cpu_online, - .suspend = intel_pstate_suspend, + .suspend = intel_cpufreq_suspend, .resume = intel_pstate_resume, .update_limits = intel_pstate_update_limits, .name = "intel_cpufreq", -- 2.33.0