From nobody Tue Feb 10 18:21:21 2026 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4E709245016; Tue, 5 Aug 2025 11:10:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754392258; cv=none; b=H7Tubhlgc04+2qBXet5UP6S83t6DBGeqK4RMRqlBlZB5b+p06+lug6v3uNpzsL66UJZ6etAcJX3TkILX6zLFHOgiu0ijo+AIyPFzLh7BsIjsScj2S9obh6sJDSu8hx/D+gL3GjYOsJq/HCd4XD4P9O79VVt8hG0kyqgqX05lfgk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754392258; c=relaxed/simple; bh=hjOL3ON5fPPF6nNMGzaUMSvif7RbckVL3EFMwbn3B9g=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=RLQYqCjUlP3Oy1wNdK5AXCYHPGGfYWj1VCS8MsLFW3ZWFJZLpmxLyu5b9o9HmixYyTUtB+iKo8fToY7/GIZCCq+ORHGF6VJEP2NJgtf6zhLaRoDSUGkT7ABK+GWK/4lpqmo1Fk/0XF5SGycLs4A8D+A+rLoa1hlCxTNr4vkKVsQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D99932BC2; Tue, 5 Aug 2025 04:10:42 -0700 (PDT) Received: from e127648.cambridge.arm.com (e127648.arm.com [10.1.27.68]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 6D8813F673; Tue, 5 Aug 2025 04:10:48 -0700 (PDT) From: Christian Loehle To: tj@kernel.org, arighi@nvidia.com, void@manifault.com Cc: linux-kernel@vger.kernel.org, sched-ext@lists.linux.dev, changwoo@igalia.com, hodgesd@meta.com, mingo@redhat.com, peterz@infradead.org, Christian Loehle , stable@vger.kernel.org Subject: [PATCH v3 1/3] sched_ext: Mark scx_bpf_cpu_rq as NULL returnable Date: Tue, 5 Aug 2025 12:10:34 +0100 Message-Id: <20250805111036.130121-2-christian.loehle@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250805111036.130121-1-christian.loehle@arm.com> References: <20250805111036.130121-1-christian.loehle@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" scx_bpf_cpu_rq() obviously returns NULL on invalid cpu. Mark it as such. While kf_cpu_valid() will trigger scx_ops_error() that leads to the BPF scheduler exiting, this isn't guaranteed to be immediate, allowing for a dereference of a NULL scx_bpf_cpu_rq() return value. Cc: stable@vger.kernel.org Fixes: 6203ef73fa5c ("sched/ext: Add BPF function to fetch rq") Signed-off-by: Christian Loehle Acked-by: Andrea Righi --- kernel/sched/ext.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 7dedc9a16281..3ea3f0f18030 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -7589,7 +7589,7 @@ BTF_ID_FLAGS(func, scx_bpf_get_online_cpumask, KF_ACQ= UIRE) BTF_ID_FLAGS(func, scx_bpf_put_cpumask, KF_RELEASE) BTF_ID_FLAGS(func, scx_bpf_task_running, KF_RCU) BTF_ID_FLAGS(func, scx_bpf_task_cpu, KF_RCU) -BTF_ID_FLAGS(func, scx_bpf_cpu_rq) +BTF_ID_FLAGS(func, scx_bpf_cpu_rq, KF_RET_NULL) #ifdef CONFIG_CGROUP_SCHED BTF_ID_FLAGS(func, scx_bpf_task_cgroup, KF_RCU | KF_ACQUIRE) #endif --=20 2.34.1