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 BC185377ECC for ; Wed, 11 Mar 2026 07:33:04 +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=1773214384; cv=none; b=fy+5fQqOBnugxOQYHlmhko/FUcNJO8AfdYTMPFEk21JsYlNxz9IQ+p+DWHiAX3jiyk3T7opcndRM6gN6ISTiclv3LDwt3AYp32bCxrM8DLo2Ejpiy4hJ24UH744svr+uGEGVoYC4bvpjYsLg96DL/hr/05B/k5qHH4Y0elsjDbE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773214384; c=relaxed/simple; bh=1L1z9Uff7sUPhdTyf+7cRKfl2c8tzKnHFazlYGo6BxY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=GuWsJR46I4y9QGXa0RNNt4iWDtjQMWsqwjgo0NbQE1aI05nSRa1CRQGe3rfFdaS9S4M2dwZEyplEIGJWZedDs3bG8AN6e72i2D1KU5Ts73S79SByWrC/Cn/GUTZCL9wYuSP0Egm1fX2N+D0kB7bMkGvI9/fOLbX3jTZYlhSKqSg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=slkZ0wQO; 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="slkZ0wQO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 66BA8C4CEF7; Wed, 11 Mar 2026 07:33:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773214384; bh=1L1z9Uff7sUPhdTyf+7cRKfl2c8tzKnHFazlYGo6BxY=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=slkZ0wQON4qI26Ggem6ZW/8rFvUos1DIPvjv+CpyBSQAxGaUUSC/72KLd4sADG3p1 70SURf20B5AtpJmaT7EeulhAlun/2wuGUCmUdlHRUemXXYcW9pow01ODgy9usO6bES /UR8CpXeAEu5Va8eF4d54GxN7Ko28p4BqDX44FYv+4CL6+2asfaC4E+L2k82UuuHaX pnfhEKkp7WillH2NV60pYgi2UVmyq+aZIZ64nyH/HM8E4gGVz1835EPEwMKhb0npcF V1fWFlfvhXlsvx0JPSz5ogqZb3k0N4ZR2liIvH1wwgFQBXzlGEY0DVyFu7WEnsU59S 3AYO3hpBJlDWA== Message-ID: <470f5363-8c84-4061-b8c3-4287d11ea6c3@kernel.org> Date: Wed, 11 Mar 2026 08:33:01 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [patch 1/4] sched/mmcid: Prevent CID stalls due to concurrent forks To: Thomas Gleixner , LKML Cc: Peter Zijlstra , Mathieu Desnoyers , Matthieu Baerts References: <20260310201009.257617049@kernel.org> <20260310202525.969061974@kernel.org> Content-Language: en-US From: Jiri Slaby Autocrypt: addr=jirislaby@kernel.org; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Thomas, On 10. 03. 26, 21:28, Thomas Gleixner wrote: > A newly forked task is accounted as MMCID user before the task is visible > in the process' thread list and the global task list. This creates the > following problem: ... > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -4729,8 +4729,12 @@ void sched_cancel_fork(struct task_struc > scx_cancel_fork(p); > } > > +static void sched_mm_cid_fork(struct task_struct *t); This introduces: [ 97s] ../kernel/sched/core.c:4711:13: warning: ‘sched_mm_cid_fork’ used but never defined [ 97s] 4711 | static void sched_mm_cid_fork(struct task_struct *t); [ 97s] | ^~~~~~~~~~~~~~~~~ on !CONFIG_SCHED_MM_CID configs. (gcc15-15.2.1+git10776-2.3) thanks, -- js suse labs