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 X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6378DC47092 for ; Wed, 2 Jun 2021 12:39:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4C033613BA for ; Wed, 2 Jun 2021 12:39:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229911AbhFBMlS (ORCPT ); Wed, 2 Jun 2021 08:41:18 -0400 Received: from mail-pl1-f172.google.com ([209.85.214.172]:46067 "EHLO mail-pl1-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229852AbhFBMlM (ORCPT ); Wed, 2 Jun 2021 08:41:12 -0400 Received: by mail-pl1-f172.google.com with SMTP id 11so1024563plk.12 for ; Wed, 02 Jun 2021 05:39:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=bLGwi9fO8fdDfHtgfYzu2Scl8l89O7XXWk70aMKsZCY=; b=cqWfgEeJn0SFsy5ID4t7Mw4kU+62niuRGJT/w1bW3N6s9iOZ3nejIs7KubZD+hSeCO 0yeKQMkP1kbWk+tHaNiyOw5lEpNyt2hqGKvjf8BKJLssw5PAugOvA8dQ8L9VxyWshnlA 2RxFUsFa5nsY2lWeAZMd3M/+Qz+kINRZEOx+bcTNiQI/UdoP8filXWYLyPy7mZkV9h0X bFkwx36HLxgb73F90P0Z/Kk2QYof0njOjbxF/NqXMfn/31fiLa8BSRzZ6OUDSANpbKDo C3jUVIGr5n+P6P6BHPmK+DCyJsqfi3SmHGG9t2DasSMUt/L5omLjpIr5Uhm1ULKzIsdv 8Jbg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=bLGwi9fO8fdDfHtgfYzu2Scl8l89O7XXWk70aMKsZCY=; b=nI0Ik4B5LD0PEQBu4d9vvx+riaP/odNU3/o3AUNOGKBN3hDjrlzFwd9ONvVxalreYi ckOnclRq9SufkC1Mm1IixN0nrGry4Jf/wxr5piBLrfWb5bfVenr82Io+HWvxBLCK8TSj oR2QmQhLIzvt7Nc4oksLj5uUu+YiAhRbf61JOdA5Y1OCNBWGwFin81MYTtuFfWaxuVnz fvFLfZPbhKh83+E/U3CbhBu0Ub6SaJJy/GE9e83EfELMND1cGvpPHp5Ef4rVu6/6mEw1 GSDqaPXv5jhIHO7UOOm9rwuXLSpvuj6q4hatreDiIfpYcawPMjHipiEmeQP9WSBs5Fst OKLA== X-Gm-Message-State: AOAM5321b+SMtHAJrP9aPQtbEePbinnRSb4A4bvMIc+c4j+prXhvsO5S 1ZSNAoklJPZvrRACKdf9Pdg= X-Google-Smtp-Source: ABdhPJxA7I6tPZMa7KkxFCelIuzmL7yzN3MFu6QCVDB4UrGVkAy34tQz5LrRrCE4uOan+jl5R1Rczw== X-Received: by 2002:a17:902:e903:b029:108:d6d0:c1d1 with SMTP id k3-20020a170902e903b0290108d6d0c1d1mr7116773pld.67.1622637498583; Wed, 02 Jun 2021 05:38:18 -0700 (PDT) Received: from bj10906pcu1.spreadtrum.com ([117.18.48.102]) by smtp.gmail.com with ESMTPSA id h18sm12586628pgl.87.2021.06.02.05.38.13 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 02 Jun 2021 05:38:18 -0700 (PDT) From: Xuewen Yan To: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com Cc: rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, linux-kernel@vger.kernel.org, zhang.lyra@gmail.com, xuewyan@foxmail.com Subject: [PATCH] sched/uclamp: Avoid setting cpu.uclamp.min bigger than cpu.uclamp.max Date: Wed, 2 Jun 2021 20:38:03 +0800 Message-Id: <20210602123803.15738-1-xuewen.yan94@gmail.com> X-Mailer: git-send-email 2.17.0 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: Xuewen Yan When setting cpu.uclamp.min/max in cgroup, there is no validating like uclamp_validate() in __sched_setscheduler(). It may cause the cpu.uclamp.min is bigger than cpu.uclamp.max. Although there is protection in cpu_util_update_eff(): “eff[UCLAMP_MIN] = min(eff[UCLAMP_MIN], eff[UCLAMP_MAX])”, it's better not to let it happen. Judging the uclamp value before setting uclamp_min/max, avoid the cpu.uclamp.min is bigger than cpu.uclamp.max. Signed-off-by: Xuewen Yan --- kernel/sched/core.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 5226cc26a095..520a2da40dc9 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -8867,6 +8867,30 @@ static ssize_t cpu_uclamp_write(struct kernfs_open_file *of, char *buf, rcu_read_lock(); tg = css_tg(of_css(of)); + + switch (clamp_id) { + case UCLAMP_MIN: { + unsigned int uc_req_max = tg->uclamp_req[UCLAMP_MAX].value; + + if (req.util > uc_req_max) { + nbytes = -EINVAL; + goto unlock; + } + break; + } + case UCLAMP_MAX: { + unsigned int uc_req_min = tg->uclamp_req[UCLAMP_MIN].value; + + if (req.util < uc_req_min) { + nbytes = -EINVAL; + goto unlock; + } + break; + } + default: + nbytes = -EINVAL; + goto unlock; + } if (tg->uclamp_req[clamp_id].value != req.util) uclamp_se_set(&tg->uclamp_req[clamp_id], req.util, false); @@ -8878,7 +8902,7 @@ static ssize_t cpu_uclamp_write(struct kernfs_open_file *of, char *buf, /* Update effective clamps to track the most restrictive value */ cpu_util_update_eff(of_css(of)); - +unlock: rcu_read_unlock(); mutex_unlock(&uclamp_mutex); -- 2.25.1