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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL 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 ACDA3C433FF for ; Tue, 30 Jul 2019 01:33:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7AB05206A2 for ; Tue, 30 Jul 2019 01:33:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="HZV5K3sn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730539AbfG3BdY (ORCPT ); Mon, 29 Jul 2019 21:33:24 -0400 Received: from mail-vs1-f73.google.com ([209.85.217.73]:54351 "EHLO mail-vs1-f73.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729221AbfG3BdY (ORCPT ); Mon, 29 Jul 2019 21:33:24 -0400 Received: by mail-vs1-f73.google.com with SMTP id b188so16471859vsc.21 for ; Mon, 29 Jul 2019 18:33:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=Frj/SS/W3AFZFbyzaOV4LWLnrMlPxcryoFLQjik2HTI=; b=HZV5K3snh9+hZYi0hyCp//JyWT/fXpO3R4ntivO3tTKVGtiJDw32+qKHYjRImOIIZW VxTiXkHj+VspcOQwMQmsA2V4AKt/XjP3LHtr1xFiKnUbnM3QWXE/wSzzzjwb8HARp0NL NnuTKiG3/MUCJOwH8yeiqO0PT9JR5nFtwF6U8A53/0E2cI+PwTcE9W+5puIoSJsXHcYY pGpqdjgsz/Gm/zNNZuQ/PWKC68R/embIB/nPMOQPIpfTsQj4rmJs4brzVzJl1hn7d19A ijF6rMV/AiriXix/ERN3pm4aTwkganjyHVi9+SBcKd4uYnPHslwXHHddmjlMGT2iycj7 WlvQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=Frj/SS/W3AFZFbyzaOV4LWLnrMlPxcryoFLQjik2HTI=; b=dGyTAdGB2sjRCiaF0uiHtDB1ZduPGX7POREz1SjE2UVV2O6GfWCp8MdTGlZ6PCuqJF 3tmJfZuEN80mp6lGKWtwT/0r2IUvvOIw14jI3mszfG0sagaOmfzzlglD5Fn6w0GXJNbA GTOoZFk8eaof46I0tmoP6mzWa8vk+kbk5DNh6yinaoAvHLPxdSYdDQnm8Zz1iC6pkMhn hHNa08pnF9pOUkDH4x0nHFcvcvJFRAsF/Xf4ABxlWUd069E15D0K2eShghlbKY+/M7kC dW5v58X3VIvojYU56dN8u5W2G1rh4++SNUbcLAGcrS6MWPkr6VToXwWuc+/ruUvzdwtQ BAjQ== X-Gm-Message-State: APjAAAXTlSfgzZQ7BA4YNS3C9BBPUt1kTwSUesdl/TrWvbXWxl8Cdn+H fOHE2DwCjUqRuY/EqJKEM2LJdMTvSgI= X-Google-Smtp-Source: APXvYqzqfX8t1uXNFJXNaDwGRiqkwrH6h4jiFWfc6T5iZhZ57KmlPWww1KkuiFIxc6pVEcoJJlMga4+hqnw= X-Received: by 2002:ab0:740e:: with SMTP id r14mr68442936uap.108.1564450403321; Mon, 29 Jul 2019 18:33:23 -0700 (PDT) Date: Mon, 29 Jul 2019 18:33:10 -0700 Message-Id: <20190730013310.162367-1-surenb@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.22.0.709.g102302147b-goog Subject: [PATCH 1/1] psi: do not require setsched permission from the trigger creator From: Suren Baghdasaryan To: mingo@redhat.com, peterz@infradead.org Cc: lizefan@huawei.com, hannes@cmpxchg.org, axboe@kernel.dk, dennis@kernel.org, dennisszhou@gmail.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@android.com, Suren Baghdasaryan , Nick Kralevich Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When a process creates a new trigger by writing into /proc/pressure/* files, permissions to write such a file should be used to determine whether the process is allowed to do so or not. Current implementation would also require such a process to have setsched capability. Setting of psi trigger thread's scheduling policy is an implementation detail and should not be exposed to the user level. Remove the permission check by using _nocheck version of the function. Suggested-by: Nick Kralevich Signed-off-by: Suren Baghdasaryan --- kernel/sched/psi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c index 7acc632c3b82..ed9a1d573cb1 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -1061,7 +1061,7 @@ struct psi_trigger *psi_trigger_create(struct psi_group *group, mutex_unlock(&group->trigger_lock); return ERR_CAST(kworker); } - sched_setscheduler(kworker->task, SCHED_FIFO, ¶m); + sched_setscheduler_nocheck(kworker->task, SCHED_FIFO, ¶m); kthread_init_delayed_work(&group->poll_work, psi_poll_work); rcu_assign_pointer(group->poll_kworker, kworker); -- 2.22.0.709.g102302147b-goog