From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 51AD3C433F5 for ; Thu, 24 Mar 2022 15:27:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Subject:Cc:To:From:Message-ID:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=OO35lx1ovTsoWpsBOSDTKmaOyJVnmUxW9RcXQVcJHyg=; b=kl0KB264fgDKNg kl2esG9k4aLhP1JrMCwNltUXB4UnY5ti+vEwCNOfqEN9QeBnmpBgRD3YB+lYY6dOqEUqXf19PxMzy kbbYGOMEDwnKuicgeYWzxzipWOtZVpjNQg6VId7DVcB02a4fxr68XxmJP85rMRttZ1t3K32fiTFys xn+34Jjln/YBxjxBeN5raD1R1IAdsY3NDWtupIEBHnmemPUWoPYUPJXDjB3BAPHBsEPab8kh8bXx3 KmfwqcMmg4B4O4V9mUAdYaleSXXkFOQs3DWKi/RdlKT1AC0KaQ0yuAd1A6JJjP6ZaIZHZ6DobJ/P7 SZnoqpE7obuMPPrgAs+A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nXPLi-00H1zA-O0; Thu, 24 Mar 2022 15:26:06 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nXPLf-00H1yo-Dv for linux-arm-kernel@lists.infradead.org; Thu, 24 Mar 2022 15:26:04 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id ED2CAB82427; Thu, 24 Mar 2022 15:26:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BCE41C340EC; Thu, 24 Mar 2022 15:25:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1648135559; bh=R3OYzmrZwFDDSW0DO3RBvLZhUI4PCrdBMhWw74wlBV0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=JVN21YWjeUESh8JX/t/jaqjXBaqHMPgUjrnoan2JgaHYiPO+NuubIXZ8rMBFmc28i eAzmQipPjHKHa+PbcqHC0kcvQUeh0WiGyfOZa9kzFGKaHqliFjjcj/1SnzRBsgw/VV zkLmZX0AbCrSmFSRACFwADSveAwP33X7UL0tH/fKAkyYOVZz525rRObhVWZJtZT2mw fgPIYqtND7YpprfJEXzEOEH90TP1Lr2KhE2pJeqZOI/8G4mMuNuUhdNniqDRAL0xiX byGvqRfAZ9QfLgmjH+pkddHtk7eABEeqzkCd/pjBlF57zC2PWdET/XJYB2fVkTaNtC K3y+LSHcPymNA== Received: from sofa.misterjones.org ([185.219.108.64] helo=why.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nXPLZ-00GjeD-A4; Thu, 24 Mar 2022 15:25:57 +0000 Date: Thu, 24 Mar 2022 15:25:56 +0000 Message-ID: <87mthf5q4b.wl-maz@kernel.org> From: Marc Zyngier To: Joakim Tjernlund Cc: "robin.murphy@arm.com" , "linux-arm-kernel@lists.infradead.org" Subject: Re: SError Interrupt on CPU0, code 0xbf000000 makes kernel panic In-Reply-To: References: <4d981e9f076986eff0b6efd7186f5797d3f5fda5.camel@infinera.com> <54c66f05-6ceb-db48-c320-c5b5b8566416@arm.com> <87o81v5tah.wl-maz@kernel.org> <1d6110707556f2b0e46f20fadd43f80b1c38e085.camel@infinera.com> <3c0c8444-4468-a571-5584-e5d902380705@arm.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: Joakim.Tjernlund@infinera.com, robin.murphy@arm.com, linux-arm-kernel@lists.infradead.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220324_082603_651602_1CA3E371 X-CRM114-Status: GOOD ( 20.18 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, 24 Mar 2022 15:11:42 +0000, Joakim Tjernlund wrote: > > On Thu, 2022-03-24 at 15:05 +0000, Robin Murphy wrote: > > Well, except when it is... try that on a Qualcomm SoC where the EL2 > > firmware will trap you and reset the system before you even know you've > > done anything wrong. If you know enough to know that an error triggered > > by accessing some address is truly benign, you know enough to avoid > > making that access in the first place. > > of course the error will be dealt with but why make bug finding > harder than it has to be? Maybe that was not clear enough from our earlier replies. Let me try again. There is *nothing* more the kernel can do. We don't even know what caused the access (read, write, earthquake or foreign power invasion). By the time we get the SError interrupt, we could well be running something altogether different because all of that is totally asynchronous *by nature*. You're just lucky that you get the response quickly enough that the kernel is still running the offending userspace. M. -- Without deviation from the norm, progress is not possible. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel