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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DA744C5519F for ; Tue, 17 Nov 2020 10:54:41 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 686512464E for ; Tue, 17 Nov 2020 10:54:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 686512464E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4Cb2rY3QCdzDqFs for ; Tue, 17 Nov 2020 21:54:37 +1100 (AEDT) Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) (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 UTF8SMTPS id 4Cb2pG6wkzzDqR7 for ; Tue, 17 Nov 2020 21:52:38 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Received: by ozlabs.org (Postfix, from userid 1034) id 4Cb2pG5DPhz9sTR; Tue, 17 Nov 2020 21:52:38 +1100 (AEDT) From: Michael Ellerman To: Paul Mackerras , Cédric Le Goater In-Reply-To: <20201105134713.656160-1-clg@kaod.org> References: <20201105134713.656160-1-clg@kaod.org> Subject: Re: [PATCH] KVM: PPC: Book3S HV: XIVE: Fix possible oops when accessing ESB page Message-Id: <160560828682.349300.13298541133310387093.b4-ty@ellerman.id.au> Date: Tue, 17 Nov 2020 21:52:38 +1100 (AEDT) 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: kvm@vger.kernel.org, Gustavo Romero , Greg Kurz , kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, David Gibson Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Thu, 5 Nov 2020 14:47:13 +0100, Cédric Le Goater wrote: > When accessing the ESB page of a source interrupt, the fault handler > will retrieve the page address from the XIVE interrupt 'xive_irq_data' > structure. If the associated KVM XIVE interrupt is not valid, that is > not allocated at the HW level for some reason, the fault handler will > dereference a NULL pointer leading to the oops below : > > WARNING: CPU: 40 PID: 59101 at arch/powerpc/kvm/book3s_xive_native.c:259 xive_native_esb_fault+0xe4/0x240 [kvm] > CPU: 40 PID: 59101 Comm: qemu-system-ppc Kdump: loaded Tainted: G W --------- - - 4.18.0-240.el8.ppc64le #1 > NIP: c00800000e949fac LR: c00000000044b164 CTR: c00800000e949ec8 > REGS: c000001f69617840 TRAP: 0700 Tainted: G W --------- - - (4.18.0-240.el8.ppc64le) > MSR: 9000000000029033 CR: 44044282 XER: 00000000 > CFAR: c00000000044b160 IRQMASK: 0 > GPR00: c00000000044b164 c000001f69617ac0 c00800000e96e000 c000001f69617c10 > GPR04: 05faa2b21e000080 0000000000000000 0000000000000005 ffffffffffffffff > GPR08: 0000000000000000 0000000000000001 0000000000000000 0000000000000001 > GPR12: c00800000e949ec8 c000001ffffd3400 0000000000000000 0000000000000000 > GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > GPR20: 0000000000000000 0000000000000000 c000001f5c065160 c000000001c76f90 > GPR24: c000001f06f20000 c000001f5c065100 0000000000000008 c000001f0eb98c78 > GPR28: c000001dcab40000 c000001dcab403d8 c000001f69617c10 0000000000000011 > NIP [c00800000e949fac] xive_native_esb_fault+0xe4/0x240 [kvm] > LR [c00000000044b164] __do_fault+0x64/0x220 > Call Trace: > [c000001f69617ac0] [0000000137a5dc20] 0x137a5dc20 (unreliable) > [c000001f69617b50] [c00000000044b164] __do_fault+0x64/0x220 > [c000001f69617b90] [c000000000453838] do_fault+0x218/0x930 > [c000001f69617bf0] [c000000000456f50] __handle_mm_fault+0x350/0xdf0 > [c000001f69617cd0] [c000000000457b1c] handle_mm_fault+0x12c/0x310 > [c000001f69617d10] [c00000000007ef44] __do_page_fault+0x264/0xbb0 > [c000001f69617df0] [c00000000007f8c8] do_page_fault+0x38/0xd0 > [c000001f69617e30] [c00000000000a714] handle_page_fault+0x18/0x38 > Instruction dump: > 40c2fff0 7c2004ac 2fa90000 409e0118 73e90001 41820080 e8bd0008 7c2004ac > 7ca90074 39400000 915c0000 7929d182 <0b090000> 2fa50000 419e0080 e89e0018 > ---[ end trace 66c6ff034c53f64f ]--- > xive-kvm: xive_native_esb_fault: accessing invalid ESB page for source 8 ! > > [...] Applied to powerpc/fixes. [1/1] KVM: PPC: Book3S HV: XIVE: Fix possible oops when accessing ESB page https://git.kernel.org/powerpc/c/75b49620267c700f0a07fec7f27f69852db70e46 cheers