From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Message-ID: <5515984D.2020801@arm.com> Date: Fri, 27 Mar 2015 17:50:05 +0000 From: Marc Zyngier MIME-Version: 1.0 Subject: Re: [RFC v2 0/5] arm64: kvm: reset hyp context for kexec References: <1427358326-3708-1-git-send-email-takahiro.akashi@linaro.org> <20150327153131.GK12400@redacted.bos.redhat.com> <55157920.3050003@arm.com> <20150327174044.GL12400@redacted.bos.redhat.com> In-Reply-To: <20150327174044.GL12400@redacted.bos.redhat.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Kyle McMartin Cc: Mark Rutland , "linaro-kernel@lists.linaro.org" , "christoffer.dall@linaro.org" , "geoff@infradead.org" , Catalin Marinas , Will Deacon , "linux-kernel@vger.kernel.org" , AKASHI Takahiro , "broonie@kernel.org" , "david.griego@linaro.org" , "kexec@lists.infradead.org" , "linux-arm-kernel@lists.infradead.org" , "freddy77@gmail.com" On 27/03/15 17:40, Kyle McMartin wrote: > On Fri, Mar 27, 2015 at 03:37:04PM +0000, Marc Zyngier wrote: >>> [ 236.260863] Kernel panic - not syncing: HYP panic: >>> [ 236.260863] PS:600003c9 PC:000003ffffff0830 ESR:0000000096000006 >> >> It would be interesting if you could find out what you have at offset >> 0x830 of hyp-init.o (the stack trace is for EL1, and is not going to >> help much). >> > > Given the alignment, i'm going to assume i'm looking at the right thing: > > 0000000000000820 <__kvm_hyp_reset>: > 820: d51c2000 msr ttbr0_el2, x0 > 824: d5033fdf isb > 828: d50c871f tlbi alle2 > 82c: d5033f9f dsb sy > 830: 10000060 adr x0, 83c <__kvm_hyp_reset+0x1c> > 834: b3403c01 bfxil x1, x0, #0, #16 > 838: d61f0020 br x1 > 83c: d53c1000 mrs x0, sctlr_el2 > > but it seems fairly implausible to be trapping on ADR x0, 1f... ... unless you've just switched TTBR0_EL2 to something slightly inappropriate, and conveniently flushed the TLBs. Also, having 0 as the exception class is fairly indicative you've fetched some crap, which reinforce my idea that the page tables are pointing to nowhere-land. I'll try to review the patches next week, maybe I'll spot something by inspection. Thanks, M. -- Jazz is not dead. It just smells funny... _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec From mboxrd@z Thu Jan 1 00:00:00 1970 From: marc.zyngier@arm.com (Marc Zyngier) Date: Fri, 27 Mar 2015 17:50:05 +0000 Subject: [RFC v2 0/5] arm64: kvm: reset hyp context for kexec In-Reply-To: <20150327174044.GL12400@redacted.bos.redhat.com> References: <1427358326-3708-1-git-send-email-takahiro.akashi@linaro.org> <20150327153131.GK12400@redacted.bos.redhat.com> <55157920.3050003@arm.com> <20150327174044.GL12400@redacted.bos.redhat.com> Message-ID: <5515984D.2020801@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 27/03/15 17:40, Kyle McMartin wrote: > On Fri, Mar 27, 2015 at 03:37:04PM +0000, Marc Zyngier wrote: >>> [ 236.260863] Kernel panic - not syncing: HYP panic: >>> [ 236.260863] PS:600003c9 PC:000003ffffff0830 ESR:0000000096000006 >> >> It would be interesting if you could find out what you have at offset >> 0x830 of hyp-init.o (the stack trace is for EL1, and is not going to >> help much). >> > > Given the alignment, i'm going to assume i'm looking at the right thing: > > 0000000000000820 <__kvm_hyp_reset>: > 820: d51c2000 msr ttbr0_el2, x0 > 824: d5033fdf isb > 828: d50c871f tlbi alle2 > 82c: d5033f9f dsb sy > 830: 10000060 adr x0, 83c <__kvm_hyp_reset+0x1c> > 834: b3403c01 bfxil x1, x0, #0, #16 > 838: d61f0020 br x1 > 83c: d53c1000 mrs x0, sctlr_el2 > > but it seems fairly implausible to be trapping on ADR x0, 1f... ... unless you've just switched TTBR0_EL2 to something slightly inappropriate, and conveniently flushed the TLBs. Also, having 0 as the exception class is fairly indicative you've fetched some crap, which reinforce my idea that the page tables are pointing to nowhere-land. I'll try to review the patches next week, maybe I'll spot something by inspection. Thanks, M. -- Jazz is not dead. It just smells funny... From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753101AbbC0RuN (ORCPT ); Fri, 27 Mar 2015 13:50:13 -0400 Received: from foss.arm.com ([217.140.101.70]:57109 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752971AbbC0RuJ (ORCPT ); Fri, 27 Mar 2015 13:50:09 -0400 Message-ID: <5515984D.2020801@arm.com> Date: Fri, 27 Mar 2015 17:50:05 +0000 From: Marc Zyngier Organization: ARM Ltd User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.4.0 MIME-Version: 1.0 To: Kyle McMartin CC: AKASHI Takahiro , Catalin Marinas , Will Deacon , Mark Rutland , "linux-arm-kernel@lists.infradead.org" , "linaro-kernel@lists.linaro.org" , "geoff@infradead.org" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "broonie@kernel.org" , "david.griego@linaro.org" , "christoffer.dall@linaro.org" , "freddy77@gmail.com" Subject: Re: [RFC v2 0/5] arm64: kvm: reset hyp context for kexec References: <1427358326-3708-1-git-send-email-takahiro.akashi@linaro.org> <20150327153131.GK12400@redacted.bos.redhat.com> <55157920.3050003@arm.com> <20150327174044.GL12400@redacted.bos.redhat.com> In-Reply-To: <20150327174044.GL12400@redacted.bos.redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 27/03/15 17:40, Kyle McMartin wrote: > On Fri, Mar 27, 2015 at 03:37:04PM +0000, Marc Zyngier wrote: >>> [ 236.260863] Kernel panic - not syncing: HYP panic: >>> [ 236.260863] PS:600003c9 PC:000003ffffff0830 ESR:0000000096000006 >> >> It would be interesting if you could find out what you have at offset >> 0x830 of hyp-init.o (the stack trace is for EL1, and is not going to >> help much). >> > > Given the alignment, i'm going to assume i'm looking at the right thing: > > 0000000000000820 <__kvm_hyp_reset>: > 820: d51c2000 msr ttbr0_el2, x0 > 824: d5033fdf isb > 828: d50c871f tlbi alle2 > 82c: d5033f9f dsb sy > 830: 10000060 adr x0, 83c <__kvm_hyp_reset+0x1c> > 834: b3403c01 bfxil x1, x0, #0, #16 > 838: d61f0020 br x1 > 83c: d53c1000 mrs x0, sctlr_el2 > > but it seems fairly implausible to be trapping on ADR x0, 1f... ... unless you've just switched TTBR0_EL2 to something slightly inappropriate, and conveniently flushed the TLBs. Also, having 0 as the exception class is fairly indicative you've fetched some crap, which reinforce my idea that the page tables are pointing to nowhere-land. I'll try to review the patches next week, maybe I'll spot something by inspection. Thanks, M. -- Jazz is not dead. It just smells funny...