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 918AA3BB57; Wed, 4 Feb 2026 22:32:42 +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=1770244362; cv=none; b=IoLcBTegPW9yI1Fgr6xUt2WUfYLfm7YJWRV3STvk54W1P6OyjYtOl3Ygzlr91629PO20Kh7iuNnLCOJ3WY+5zS8stNPhF6yx5y4+Yk5IDmJOSw/1w1O910wdo5SwkD3j4M93CsVdtBJu9P54B36fl8HarBjN5Mg5hImpNozEw0s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770244362; c=relaxed/simple; bh=7j/t1KHfrd7ogDja6DlFcKyM21ozIktyxx96BUt15Eg=; h=Date:Message-ID:From:To:Cc:Subject; b=d9UMcdwhwfvn2u5Kun84J9/BsH/MRBaCGAGfxcNM/+TLmc4IwfRggvzhJ2AJs/P/xdbEBzbLP9DYHedkJVCBVRGV/DhIeOTgxxBLsRIcolHKow4CYIIaci4w6NzwgorNU++WBWioaoCfCDGkqj/Cc5B+04qsifksEO1u9jsSYso= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Eb3AB9ky; 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="Eb3AB9ky" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0ECAFC16AAE; Wed, 4 Feb 2026 22:32:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770244362; bh=7j/t1KHfrd7ogDja6DlFcKyM21ozIktyxx96BUt15Eg=; h=Date:From:To:Cc:Subject:From; b=Eb3AB9ky38eJTJSPy4ms06kSR11x8DI1GJ15/zhOjP7WA8tmEZFX3e9nODgg/b517 8CdkxqrLbGQ/7Ivez19rV+71Ab0Lp1+hRAvifXqkNcw0lb8TuYLU9Mh1fuVQBneZ6D CZnyfS9WsKHeHvgfCRRRCENvLB9N6pH1Pq/08/TpZGTe0BOSFqobfhaTzzxGj06QFF 4t4Fz6BxZTgD2zCisfRZwUXK7GdyoB7Aik5hlw5ApLCPTdOuZhazpDmTkYVUZnxPjQ IOfH7ZDIXcsVAz54EfPd3LZlm+5nJn2K9LZOtIs8Dl2Ti3Lo/nNJHxEpkrvHfHvjZa WfvJnipJ9ENlg== Date: Wed, 04 Feb 2026 12:32:41 -1000 Message-ID: <403d62bc430249eb2904652103e4efa0@kernel.org> From: Tejun Heo To: Linus Torvalds Cc: David Vernet , Andrea Righi , Changwoo Min , Emil Tsalapatis , sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [GIT PULL] sched_ext: Fix for v6.19-rc8 Precedence: bulk X-Mailing-List: sched-ext@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Hi, Linus. This is a critical regression fix for a change introduced in this cycle. The cgroup exit ordering fix (7900aa699c34) which moved sched_ext_free() to finish_task_switch() created a race window where sched_class operations could be invoked on dead tasks after sched_ext_dead() already ran, leading to invalid SCX task state transitions and NULL pointer dereferences. Thanks. The following changes since commit c9894e6f0160414b57e895332c580cf5c8da6780: tools/sched_ext: update scx_show_state.py for scx_aborting change (2025-12-28 06:11:26 -1000) are available in the Git repository at: https://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext.git tags/sched_ext-for-6.19-rc8-fixes for you to fetch changes up to 0eca95cba2b7bf7b7b4f2fa90734a85fcaa72782: sched_ext: Short-circuit sched_class operations on dead tasks (2026-02-04 12:22:11 -1000) ---------------------------------------------------------------- sched_ext: Fixes for v6.19-rc8 - Fix race where sched_class operations (sched_setscheduler() and friends) could be invoked on dead tasks after sched_ext_dead() already ran, causing invalid SCX task state transitions and NULL pointer dereferences. This was a regression from the cgroup exit ordering fix which moved sched_ext_free() to finish_task_switch(). ---------------------------------------------------------------- Tejun Heo (1): sched_ext: Short-circuit sched_class operations on dead tasks kernel/sched/ext.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) -- tejun