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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 CC3A6C27C4F for ; Wed, 26 Jun 2024 09:28:37 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=ellerman.id.au header.i=@ellerman.id.au header.a=rsa-sha256 header.s=201909 header.b=h99XaPul; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4W8GbR0kwnz3cNj for ; Wed, 26 Jun 2024 19:28:35 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=ellerman.id.au header.i=@ellerman.id.au header.a=rsa-sha256 header.s=201909 header.b=h99XaPul; dkim-atps=neutral Received: from mail.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4W8GZd2C62z30T7 for ; Wed, 26 Jun 2024 19:27:53 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ellerman.id.au; s=201909; t=1719394066; bh=Z0cCuqbCi6qeO6wyfodeUIhXjtgD405yHuP4v2jv4aU=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=h99XaPulVs60hJoiREYh00S73G17Yh76fEEhsz8AUNUeRvRgzaiKHp14NpiY5hZHB Ou+uGW7/5X4esOKXkwam45RV+bQgrN9pWprwAR/XfFX12ll+NfHbWYxwdHSN87d1C9 5U0d380qVLVilJNG5oYNWGHRqH7n8FjZ6GJyps348oEmEuKVPQbvTIYbnG+IogUfL4 2+3PCmfUzQgXPqM2R93lUySAU5Z4nCobGYry/HyrPQ7yOz4KHACF2PHeyKAEe/kNKm QHizITY9zX1M+cRXeLpT26+yxHrDQMeaROJu7PimI8+cc06toOjMkK9n0BgGQG91Dj nGdflU55OjXww== Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4W8GZT6JRtz4wb2; Wed, 26 Jun 2024 19:27:45 +1000 (AEST) From: Michael Ellerman To: Nicholas Piggin , linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH] powerpc/pseries: Fix scv instruction crash with kexec In-Reply-To: <20240625134047.298759-1-npiggin@gmail.com> References: <20240625134047.298759-1-npiggin@gmail.com> Date: Wed, 26 Jun 2024 19:27:45 +1000 Message-ID: <87sex0oxym.fsf@mail.lhotse> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nicholas Piggin , Sourabh Jain Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Nicholas Piggin writes: > kexec on pseries disables AIL (reloc_on_exc), required for scv > instruction support, before other CPUs have been shut down. This means > they can execute scv instructions after AIL is disabled, which causes an > interrupt at an unexpected entry location that crashes the kernel. > > Change the kexec sequence to disable AIL after other CPUs have been > brought down. > > As a refresher, the real-mode scv interrupt vector is 0x17000, and the > fixed-location head code probably couldn't easily deal with implementing > such high addresses so it was just decided not to support that interrupt > at all. > > Reported-by: Sourabh Jain Was this reported publicly? I don't remember it. cheers