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 4DAA61DEFE8; Tue, 2 Jun 2026 22:09:13 +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=1780438154; cv=none; b=nxEsJq+nLxTke8N691vbAsA3sxQZDVX5WxMrUsGMeAM9+30bHBb7a2WQIpJ/3L9JVQ+FWOR7SXMXckP+1o4wUuwXFYHO1bbX9nNnZNdlDvOQVy+HbH3vjTcKeG2iqHxYU5spgsEKYWmL+Fqy8+/+GUsR4mCqCg5GS1A2RLQPlnE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780438154; c=relaxed/simple; bh=GC8FjW8eAZZqSEHEtIR7QWUFGmOxnTJ1Nu6ikhwgeQA=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References; b=SLcSrqtJOKocTBzje9AMR7udXd4oxOm1hxrQId8z3nTzsXXHtj1ladl+A80cRGxYY723Gf/TuqdSM4XWoUl1FMAijufiZpginbMIz9+4AY7UCGOIfGRtgfx1z6B/bgN6VB934zNUiEwXcRtmSENxRzg+L9+Oomg4z9+tsu1EK7A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LezzoyJO; 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="LezzoyJO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D634F1F00893; Tue, 2 Jun 2026 22:09:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780438153; bh=GC8FjW8eAZZqSEHEtIR7QWUFGmOxnTJ1Nu6ikhwgeQA=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=LezzoyJOYE8E5dHI2kTrX2OlVW8csGBo71kbltsEIXgUg7b3ekMDmNG6Bb/sOKisP mBAFZPTtkKRnHQD4pmKo5hbhuMNRyNUbc3HkAm4ILzgTZJrmEO2mPVL83QV0lxShjh p6zpwO8u9X+6fFWJDWQSKUAh5SKN43wkDR4DLRaQ00acWtw+On1hfmIWtMot7YOGsO xUGHWBXkhk/Ujm73YVH8nRDI4SCq8HH8XZzGujRj1bbkqOfqznKCS52wriKePD8x2X bcEt7+QCl4d/m8RdICey8u64NsLkzsUmcx99k6ZMKkmFyW+YpDiE98wvCCVl1FJfyo gAdpWQlO7N+AQ== Date: Tue, 02 Jun 2026 12:09:11 -1000 Message-ID: <8f133924fbf8d259340f3057e505f663@kernel.org> From: Tejun Heo To: bot+bpf-ci@kernel.org, void@manifault.com, arighi@nvidia.com, changwoo@igalia.com, ast@kernel.org, andrii@kernel.org, daniel@iogearbox.net, martin.lau@linux.dev, memxor@gmail.com Cc: peterz@infradead.org, catalin.marinas@arm.com, will@kernel.org, tglx@kernel.org, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, akpm@linux-foundation.org, david@kernel.org, rppt@kernel.org, emil@etsalapatis.com, sched-ext@lists.linux.dev, bpf@vger.kernel.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, eddyz87@gmail.com, yonghong.song@linux.dev, clm@meta.com, ihor.solodrai@linux.dev Subject: Re: [PATCH bpf-next] bpf: Replace scratch PTE atomically when allocating arena pages In-Reply-To: References: <20260601183728.1800490-1-tj@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: On Mon, Jun 01, 2026 at 08:15:34PM +0000, bot+bpf-ci@kernel.org wrote: > After the real page is installed without a flush, can that stale > kaddr -> scratch_page translation persist, so that later kernel-side > accesses at kaddr reach the shared per-arena scratch page instead of > the freshly allocated page? It can on x86, but it's harmless: that CPU faulted on an unallocated address and got scratch-recovered, so reaching either the scratch or the real page is fine. No flush needed. Thanks. -- tejun