From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH 00/11] APEI in_nmi() rework and arm64 SDEI wire-up Date: Mon, 19 Feb 2018 22:05:23 +0100 Message-ID: <20180219210523.GA17922@pd.tnic> References: <20180215185606.26736-1-james.morse@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20180215185606.26736-1-james.morse@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: James Morse Cc: Rafael Wysocki , Tony Luck , Xie XiuQi , linux-mm@kvack.org, Marc Zyngier , Catalin Marinas , Tyler Baicar , Will Deacon , Dongjiu Geng , linux-acpi@vger.kernel.org, Punit Agrawal , linux-arm-kernel@lists.infradead.org, Naoya Horiguchi , kvmarm@lists.cs.columbia.edu, Christoffer Dall , Len Brown List-Id: kvmarm@lists.cs.columbia.edu On Thu, Feb 15, 2018 at 06:55:55PM +0000, James Morse wrote: > Hello! > > The aim of this series is to wire arm64's SDEI into APEI. > > What's SDEI? Its ARM's "Software Delegated Exception Interface" [0]. It's > used by firmware to tell the OS about firmware-first RAS events. > > These Software exceptions can interrupt anything, so I describe them as > NMI-like. They aren't the only NMI-like way to notify the OS about > firmware-first RAS events, the ACPI spec also defines 'NOTFIY_SEA' and > 'NOTIFY_SEI'. > > (Acronyms: SEA, Synchronous External Abort. The CPU requested some memory, > but the owner of that memory said no. These are always synchronous with the > instruction that caused them. SEI, System-Error Interrupt, commonly called > SError. This is an asynchronous external abort, the memory-owner didn't say no > at the right point. Collectively these things are called external-aborts > How is firmware involved? It traps these and re-injects them into the kernel > once its written the CPER records). Thank you about those! This is how people should write 0/N introductory messages with fancy new abbreviations. :-) -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.