From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 775F9541E67; Thu, 15 Oct 2026 17:06:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792083978; cv=none; b=ZATuJLRA1CFfFPMtcNjhTtlnVRRMJaydLLdOLsNG6s/VbChsHMiwdx2LJXOqt4/dRdLiSHYMKxbPJZiHH5Tbs+xJXjFgLRYPrHEyRiAsf/cHg0Z7TeAig7DGMbiOIqPtjW/V/38OoTms2TEUHVxRsTx+FzsxpOprKMSQpfodID0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792083978; c=relaxed/simple; bh=KjodMYbnA9m91a6xcSvuCss6trwsthbdX+Ns66ZfJnk=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References; b=rPE2rVJW+opjAfL6iXIHLKa/HprBSFL/vS4uqyu1caVqV4PFJNbiGmUpmNSi9yLgMFyUQda/dbcED5TAm+WFIXlJ1E8rOTo7gsWllwHUl6RpmNZfueVlfJihB6wHWS5Bu48+i0oit5uChvUN1CkSui/rUQVq2NfnZyoehm8xRLU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZRo7Ui4m; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ZRo7Ui4m" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A311A1F000C4; Thu, 15 Oct 2026 17:06:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792083963; bh=FW422e6T9ArO/ZaeXBPKkSsp7mQcTXDZLhUpxnq/rR4=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=ZRo7Ui4m/YEGepM7LywTBGD+o4zs/G9QI1IqfXPGubjhcONWu6XaavQ+fQ7lV3RFC GfpcUmL5FU0itzz/xywHZwZabQi5aPev1/5CP2EWak1YFAZtqd+pnNMEi/LxZyzvzl Cjbb+jy7YiGJi2GzbFrOkR6Cnt2y4i7eVScLna+EJn1mMSU9lZeUufQ+/X7RZXfk3/ Kb6u1z2PZax11nH2m6x0anHUeCWhpOCuYcFH0i2aClY6/iD8GssMyKtzeNZbIzQewF 80B9XXZax042ureI26vypWTnoECyBKdx089vwikNhyKHZbCm2QZFdMuzg+bXyh3bcu dP+ivXuFUUuVQ== Date: Thu, 15 Oct 2026 07:06:02 -1000 Message-ID: <4e063370a5b974364587fabd04c1aaf7@kernel.org> From: Tejun Heo To: Puranjay Mohan Cc: bpf@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Kumar Kartikeya Dwivedi , Song Liu , Yonghong Song , David Vernet , Andrea Righi , Changwoo Min , sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH bpf-next v4 0/3] bpf, x86: Support fetching AND/OR/XOR atomics in arena In-Reply-To: <20261014125017.1426212-1-puranjay@kernel.org> References: <20261014125017.1426212-1-puranjay@kernel.org> Precedence: bulk X-Mailing-List: sched-ext@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Hello, Puranjay. On Wed, Oct 14, 2026 at 05:50:10AM -0700, Puranjay Mohan wrote: > A fetching AND/OR/XOR against arena memory is rejected on x86-64: > > BPF_ATOMIC stores into R1 arena is not allowed - 1/3: A fetching atomic through a number now fails to load with an empty verifier log, where it used to get the message above. That seems problematic. Can that case keep an error message? - 3/3: sched_ext/for-7.4 already synced a cid.bpf.h from scx which probes for the fetching atomics and keeps the CAS loop as the old-kernel fallback, so this conflicts with it. I'll pull bpf/for-next into sched_ext/for-7.4 and we can do the modifications on top. For 1/3 and 2/3, Acked-by: Tejun Heo Thanks. -- tejun