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 D06BE3932DC; Sun, 10 May 2026 13:55:32 +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=1778421332; cv=none; b=blrcUaEOx/BoNwmOlJThTrPCvJEAEe5rom454O2b1Z6ePfSN12QHaU4CAYbAWXZNFSTnTUonj4nrPT1wigyoSTAsuPevtFnF6PNQCKqVe4MuBNGdYwlmC/g9z2CCZtAXBOngWFYIwa1KgqFijXg4DI+Rzu9mv4+8sX6RMdyYtVM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778421332; c=relaxed/simple; bh=FxRKigehiLGN3UQfHHA5rga4kgJBTzlRe/0ULSv66bw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iSqbZNkCR36raXFu27RP+mFeZ9m0iGgk0z1M52+kgGhoTF1ZjpWhEgmqh87aNOMdQ69Fg7H7ObITK9dvOx/OvA1uXVYrg0HFICdYgMZSd4rwQY7Svo6X9I1QBJvWF0DvTFHISO+ziqVvw31oxNZnRkfJOobiApsoDvvqbKybrVs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pCvx/nXr; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pCvx/nXr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 67DBAC2BCB8; Sun, 10 May 2026 13:55:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778421332; bh=FxRKigehiLGN3UQfHHA5rga4kgJBTzlRe/0ULSv66bw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pCvx/nXr3aBfdCtbSjVXkvK6db2RXP1rJBwcuZUOg/m4AfqSC+MXX5L99Gy/zxvK7 OL2/C7LFEVsi1KnACuq317jmOBGlLQkvjuOfP+i/DKVnQiMSsPotuA+U/VHdvFy/Wr HHnCkWUkYbpKlx2eeSHaPLIHtOiiCD1ZOYcd+uB2lFUOOP0OtVkTV9s2XNkA5Vz1Fv BcMnSp1CMc5zV5N/zXhwJipFkZw97amsZ/b937CphnkkGpEhFO/6IuUcWoVOs3YwPc SlLu268tKdCxKaQVb5Xeg3QHB0cyOzMD4wceprF0CXoCkgoD/1AJAdfBUBt5IWnj3w 808ZNjmzyhzIw== From: Tejun Heo To: suzhidao@xiaomi.com Cc: void@manifault.com, arighi@nvidia.com, changwoo@igalia.com, emil@etsalapatis.com, sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org, Tejun Heo Subject: Re: [PATCH v2] sched_ext: Fix sched_ext_dead() race with scx_root_enable_workfn() Date: Sun, 10 May 2026 03:55:31 -1000 Message-ID: <20260510135531.2291252-1-tj@kernel.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260506054001.1105522-1-suzhidao@xiaomi.com> References: <20260429133155.3825247-1-suzhidao@xiaomi.com> <20260506054001.1105522-1-suzhidao@xiaomi.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hello, Thanks for the report and the patches. The same race window also affects the analogous sub-sched paths and the wrapper-disable paths trip on the NONE state that scx_fail_parent() leaves behind, so I ended up taking a more invasive route - extending the task state machine with SCX_TASK_INIT_BEGIN and SCX_TASK_DEAD - rather than continuing with your localized fix. Posted as a 6-patch series: https://lore.kernel.org/all/20260510074113.2049514-1-tj@kernel.org/ Thanks. -- tejun