From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793878695; b=GIwaDe/tmFEVl3Iuk3GkZMf0fpqpEnqGo1y2XMQmzgX/6ZlxBPH8Ri8JjJUMuh4W+AWJ eubYRFDfriatf9rh+u7u32vd6LePzNlUqo65t5oVacCbl9oXjEhRtHV0hb+Uhfe1ItHye r8ira+AhLHXfYm8a5XbmgM+XMaFNqtEZSNzBq6ex/2y55M4ec4/hcOBcRB3+vXaurDWAn OH0rt8+rhn8Ya69awNzcbUIX0mZZ1J0vgKpePnrBUowSy3zoY2KLTlXOJDBAqmDpbnnv4 /l+DaY6iZQ0IDA0DKRgp1yqI4xoP2acR/L1lDVwBRLxefNk0Z2/og8K1e2RShwMBxrA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793878695; h=Received:DKIM-Signature:Received:Received:X-ME-Sender:X-ME-Received: X-ME-Proxy-Cause:X-ME-Proxy:Feedback-ID:Received:Date:From:To:Cc: Subject:Message-ID:References:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; bh=tbsBhorpX5/hg11/oBkLoGN5x3wli6X3ebAisCWgK2c=; b=vSM6wgKy8N/PWyK3kmzs4lDESG1YZPfoeHnkLxwPIczUB/vDmZS4PfM2c0IZiWmYjPJp wm8ztFpOnA6ne4edxh722riSbIOeD8B5j3OOSUTqrTfhiAqDJVScg+Qqib5AMBHqp0iNa BDVd0uoO1Wu1hejWGDLSGUYw5dS94zk8SthF5iVH7bJEO7HFKoAMTZe+E/kSjufzP7bRn JY/KpxM6iHcJhODNwd6yJ200Sn5xXg8dZfSDxEz9bokCd7uca9c+2m64jGX2ERTomfGaF XNaXy0jc5aCaOCQgi+UhCi+xR8/DwBkY1uRA07w74azPPHE8cdQNoRZkmyOwwXXvMpA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=M9X+iDw2; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5BEBD606A31B for ; Thu, 5 Nov 2026 11:38:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=M9X+iDw2 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 171B81F000C1; Thu, 5 Nov 2026 11:38:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793878694; bh=tbsBhorpX5/hg11/oBkLoGN5x3wli6X3ebAisCWgK2c=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=M9X+iDw2ORrpPUaDkz7MrCQc+gRQbprFWySehjB2KG4rXWODD4igi+duJmMoSnlRl kopf5u3YgN78VtyHl01cXCmfizipTxNpk9SOEBgAAr3E8HL0zkMhopiP05LtJceWrY ED1WnjC2S+xlCNv5zBI0n69ItkHBN5Wv4H+yDUCiuDnOO8jDRfjazJZOuRPLJcFlvn o7n1fCqLc0w49cechdoVyDSWEqcr3LondEMEu5s12GyhP//iaF4cgVTlLRiCFKnT7n YVnsMU9vpesAWl+HTeCTqQOCSgRLztuF/dP3vfs26f6kTtzbNGF3sa+mLKXdYiBHiM st1wzmJSheO8g== Received: from phl-compute-05.internal (phl-compute-05.internal [10.202.2.45]) by mailfauth.ams.internal (Postfix) with ESMTP id 6D272198003A; Thu, 5 Nov 2026 06:38:10 -0500 (EST) Received: from phl-frontend-04 ([10.202.2.163]) by phl-compute-05.internal (MEProxy); Thu, 05 Nov 2026 06:38:12 -0500 X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: dmFkZTFgCBY0H5ERCpEWHMWeRovHwsuqR+Zb+dTNF6i0Wx6f7bDy0HWpqxM/ilEd3SmjwZ vjJAUFeZ/zBNEC3KI2YM+ad6PmkKx4ukR8n5J8nEiKNFWVXyvayr0881g5/mna2LEZcqam I8+YZ6HPM1KFewLEYnolCm4NMYZG7n/P92+sSLWoLbVmG9/cM8ddAdCMCI/zzzsvgYhWH/ U0/un/WLwaEnnvjrs8TM7ghH3lFOprirTdMYV8lQR2O11uKvbkktYbVoKk6QpJLoKDlpMF htE8GiRINFSaJ74JopyvAxB/OOc/3hMfEeCHd9+w/qJ7P2Stp8TOD//K8G5YrP+v/+gaSn rqCy4qK4skVM4GvMeNcty2X+jEl/W9vNjpmQZj7NSp3HcqiH2ME/3kKmcO4vdSZxh38I7J hm8EEkedoYry5QczVgTb4gK5JbJXByKI9E/D12mIdar2rGXlzoLvqb04B6flvcbpWOUqwa xWodXioGRteUh8SVPRSz+jSe33SB4Q/D/xWYp5buKmkf/K7DPwLQz3JakHyyAf5XP2v2k0 ypce1ZV2IEOqx+byeARzy6zXkHBuMXRBPo8mflhhICtYm4kEfDGfscjBvW7nHL41WdHa5c 0QTbN74SZIEmIktDxDq1ZWXtR6RQcPexInTsmSlhYzkCOES6HqFBvU3HrZ1g X-ME-Proxy: Feedback-ID: i10464835:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Thu, 5 Nov 2026 06:38:09 -0500 (EST) Date: Thu, 5 Nov 2026 11:38:08 +0000 From: Kiryl Shutsemau To: Usama Arif Cc: Catalin Marinas , Will Deacon , Mark Rutland , James Morse , Marc Zyngier , Doug Anderson , Breno Leitao , Dawei Li , mrigendrachaubey , kernel-team@meta.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH 1/2] arm64: sdei: Run the event handler on the kernel vectors Message-ID: References: <20261104180936.2981070-2-kas@kernel.org> <20261104182842.3436759-1-usama.arif@linux.dev> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261104182842.3436759-1-usama.arif@linux.dev> On Wed, Nov 04, 2026 at 10:28:41AM -0800, Usama Arif wrote: > Would doing the swap in __sdei_handler(), around the whole NMI > entry and exit pair, close that window? Yes. The WARNs you point at only fire when context tracking is already broken, but the same window has tracepoints: trace_hardirqs_off_finish() fires irq_disable exactly when the event lands in user space, and a BPF program attached there can fault. It applies to 2/2 too: anything that traps in irqentry_nmi_enter() overwrites ELR, ESR and FAR before do_sdei_event() saves them. I'll move both into __sdei_handler(), around irqentry_nmi_enter() and irqentry_nmi_exit(), in v2. do_sdei_event() still needs the interrupted VBAR for the IRQ-like resume, so it will get it as an argument. -- Kiryl Shutsemau / Kirill A. Shutemov