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=-13.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 5FC9BC433DF for ; Sun, 14 Jun 2020 14:54:53 +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 93B11206A4 for ; Sun, 14 Jun 2020 14:54:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=xenosoft.de header.i=@xenosoft.de header.b="qoSaqPPS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 93B11206A4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=xenosoft.de 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 49lHYj2Z20zDqSJ for ; Mon, 15 Jun 2020 00:54:49 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.helo=mo4-p02-ob.smtp.rzone.de (client-ip=81.169.146.168; helo=mo4-p02-ob.smtp.rzone.de; envelope-from=chzigotzky@xenosoft.de; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=xenosoft.de Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=xenosoft.de header.i=@xenosoft.de header.a=rsa-sha256 header.s=strato-dkim-0002 header.b=qoSaqPPS; dkim-atps=neutral Received: from mo4-p02-ob.smtp.rzone.de (mo4-p02-ob.smtp.rzone.de [81.169.146.168]) (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 49lHVz3YplzDqQH for ; Mon, 15 Jun 2020 00:52:24 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1592146338; s=strato-dkim-0002; d=xenosoft.de; h=In-Reply-To:Date:Message-ID:From:References:Cc:To:Subject: X-RZG-CLASS-ID:X-RZG-AUTH:From:Subject:Sender; bh=eFPCeIIF25kt0fObkS64iRLkTdurcInQw6zzOXBLyT0=; b=qoSaqPPSlExEUt+mooxXiY/HpDI7onnsIMwhNLDIRjcZy+q1PFnQfdZA8xK/mN1/vL JI8GdPri5UCeKB2nElo7VA5WD2E4FZ2TkhiCeYPzfIIv4G060ZIxx0yvqbMGgyZG6zGf Z5qyWpuq0oeXt37hmnoqZ/wB2HuvLSmGBI+HEfxUmvjUZfooeT7IUeSPGVEjkaSVHzea F5R7BeXB1LHF7TYEcbcEVJCL6Hze5gXlL2wu/ZA6MzdZSUMKOtqaF8YLHeOAnUFmWZMW Hmo+nNDrPb/kfUEfgs6a1yH5bFfYVKKyaTXkFF64nikenQ4cAyqgHv0fQRlig+XclbK6 KqWg== X-RZG-AUTH: ":L2QefEenb+UdBJSdRCXu93KJ1bmSGnhMdmOod1DhGM4l4Hio94KKxRySfLxnHfJ+Dkjp5DdBJSrwuuqxvPhSI1Vi9hdbute3wuvmUTfEdg9AyQ==" X-RZG-CLASS-ID: mo00 Received: from [IPv6:2a02:8109:89c0:ebfc:15f9:f3ba:c3bc:6875] by smtp.strato.de (RZmta 46.10.4 AUTH) with ESMTPSA id m08564w5EEqA5yF (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits)) (Client did not present a certificate); Sun, 14 Jun 2020 16:52:10 +0200 (CEST) Subject: Re: PowerPC KVM-PR issue To: Nicholas Piggin , "kvm-ppc@vger.kernel.org" , linuxppc-dev References: <067BBAB3-19B6-42C6-AA9F-B9F14314255C@xenosoft.de> <014e1268-dcce-61a3-8bcd-a06c43e0dfaf@csgroup.eu> <7bf97562-3c6d-de73-6dbd-ccca275edc7b@xenosoft.de> <87tuznq89p.fsf@linux.ibm.com>

<7e859f68-9455-f98f-1fa3-071619fa1731@xenosoft.de> <54082b17-31bb-f529-2e9e-b84c5a5aa9ec@xenosoft.de> <1592139127.g2951cl0h6.astroid@bobo.none> From: Christian Zigotzky Message-ID: Date: Sun, 14 Jun 2020 16:52:10 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: <1592139127.g2951cl0h6.astroid@bobo.none> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: de-DE 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: Darren Stevens , "R.T.Dickinson" , Christian Zigotzky Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 14 June 2020 at 02:53 pm, Nicholas Piggin wrote: > Excerpts from Christian Zigotzky's message of June 12, 2020 11:01 pm: >> On 11 June 2020 at 04:47 pm, Christian Zigotzky wrote: >>> On 10 June 2020 at 01:23 pm, Christian Zigotzky wrote: >>>> On 10 June 2020 at 11:06 am, Christian Zigotzky wrote: >>>>> On 10 June 2020 at 00:18 am, Christian Zigotzky wrote: >>>>>> Hello, >>>>>> >>>>>> KVM-PR doesn't work anymore on my Nemo board [1]. I figured out >>>>>> that the Git kernels and the kernel 5.7 are affected. >>>>>> >>>>>> Error message: Fienix kernel: kvmppc_exit_pr_progint: emulation at >>>>>> 700 failed (00000000) >>>>>> >>>>>> I can boot virtual QEMU PowerPC machines with KVM-PR with the >>>>>> kernel 5.6 without any problems on my Nemo board. >>>>>> >>>>>> I tested it with QEMU 2.5.0 and QEMU 5.0.0 today. >>>>>> >>>>>> Could you please check KVM-PR on your PowerPC machine? >>>>>> >>>>>> Thanks, >>>>>> Christian >>>>>> >>>>>> [1] https://en.wikipedia.org/wiki/AmigaOne_X1000 >>>>> I figured out that the PowerPC updates 5.7-1 [1] are responsible for >>>>> the KVM-PR issue. Please test KVM-PR on your PowerPC machines and >>>>> check the PowerPC updates 5.7-1 [1]. >>>>> >>>>> Thanks >>>>> >>>>> [1] >>>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d38c07afc356ddebaa3ed8ecb3f553340e05c969 >>>>> >>>>> >>>> I tested the latest Git kernel with Mac-on-Linux/KVM-PR today. >>>> Unfortunately I can't use KVM-PR with MoL anymore because of this >>>> issue (see screenshots [1]). Please check the PowerPC updates 5.7-1. >>>> >>>> Thanks >>>> >>>> [1] >>>> - >>>> https://i.pinimg.com/originals/0c/b3/64/0cb364a40241fa2b7f297d4272bbb8b7.png >>>> - >>>> https://i.pinimg.com/originals/9a/61/d1/9a61d170b1c9f514f7a78a3014ffd18f.png >>>> >>> Hi All, >>> >>> I bisected today because of the KVM-PR issue. >>> >>> Result: >>> >>> 9600f261acaaabd476d7833cec2dd20f2919f1a0 is the first bad commit >>> commit 9600f261acaaabd476d7833cec2dd20f2919f1a0 >>> Author: Nicholas Piggin >>> Date: Wed Feb 26 03:35:21 2020 +1000 >>> >>> powerpc/64s/exception: Move KVM test to common code >>> >>> This allows more code to be moved out of unrelocated regions. The >>> system call KVMTEST is changed to be open-coded and remain in the >>> tramp area to avoid having to move it to entry_64.S. The custom >>> nature >>> of the system call entry code means the hcall case can be made more >>> streamlined than regular interrupt handlers. >>> >>> mpe: Incorporate fix from Nick: >>> >>> Moving KVM test to the common entry code missed the case of HMI and >>> MCE, which do not do __GEN_COMMON_ENTRY (because they don't want to >>> switch to virt mode). >>> >>> This means a MCE or HMI exception that is taken while KVM is >>> running a >>> guest context will not be switched out of that context, and KVM won't >>> be notified. Found by running sigfuz in guest with patched host on >>> POWER9 DD2.3, which causes some TM related HMI interrupts (which are >>> expected and supposed to be handled by KVM). >>> >>> This fix adds a __GEN_REALMODE_COMMON_ENTRY for those handlers to add >>> the KVM test. This makes them look a little more like other handlers >>> that all use __GEN_COMMON_ENTRY. >>> >>> Signed-off-by: Nicholas Piggin >>> Signed-off-by: Michael Ellerman >>> Link: >>> https://lore.kernel.org/r/20200225173541.1549955-13-npiggin@gmail.com >>> >>> :040000 040000 ec21cec22d165f8696d69532734cb2985d532cb0 >>> 87dd49a9cd7202ec79350e8ca26cea01f1dbd93d M arch >>> >>> ----- >>> >>> The following commit is the problem: powerpc/64s/exception: Move KVM >>> test to common code [1] >>> >>> These changes were included in the PowerPC updates 5.7-1. [2] >>> >>> Another test: >>> >>> git checkout d38c07afc356ddebaa3ed8ecb3f553340e05c969 (PowerPC updates >>> 5.7-1 [2] ) -> KVM-PR doesn't work. >>> >>> After that: git revert d38c07afc356ddebaa3ed8ecb3f553340e05c969 -m 1 >>> -> KVM-PR works. >>> >>> Could you please check the first bad commit? [1] >>> >>> Thanks, >>> Christian >>> >>> >>> [1] >>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9600f261acaaabd476d7833cec2dd20f2919f1a0 >>> [2] >>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d38c07afc356ddebaa3ed8ecb3f553340e05c969 >> Hi All, >> >> I tried to revert the __GEN_REALMODE_COMMON_ENTRY fix for the latest Git >> kernel and for the stable kernel 5.7.2 but without any success. There >> was lot of restructuring work during the kernel 5.7 development time in >> the PowerPC area so it isn't possible reactivate the old code. That >> means we have lost the whole KVM-PR support. I also reported this issue >> to Alexander Graf two days ago. He wrote: "Howdy :). It looks pretty >> broken. Have you ever made a bisect to see where the problem comes from?" >> >> Please check the KVM-PR code. > Does this patch fix it for you? > > The CTR register reload in the KVM interrupt path used the wrong save > area for SLB (and NMI) interrupts. > > Fixes: 9600f261acaaa ("powerpc/64s/exception: Move KVM test to common code") > Reported-by: Christian Zigotzky > Signed-off-by: Nicholas Piggin > --- > arch/powerpc/kernel/exceptions-64s.S | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S > index e70ebb5c318c..fa080694e581 100644 > --- a/arch/powerpc/kernel/exceptions-64s.S > +++ b/arch/powerpc/kernel/exceptions-64s.S > @@ -270,7 +270,7 @@ BEGIN_FTR_SECTION > END_FTR_SECTION_IFSET(CPU_FTR_CFAR) > .endif > > - ld r10,PACA_EXGEN+EX_CTR(r13) > + ld r10,IAREA+EX_CTR(r13) > mtctr r10 > BEGIN_FTR_SECTION > ld r10,IAREA+EX_PPR(r13) > @@ -298,7 +298,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) > > .if IKVM_SKIP > 89: mtocrf 0x80,r9 > - ld r10,PACA_EXGEN+EX_CTR(r13) > + ld r10,IAREA+EX_CTR(r13) > mtctr r10 > ld r9,IAREA+EX_R9(r13) > ld r10,IAREA+EX_R10(r13) Many thanks for the fix! I will test it with the RC1 tomorrow. -- Christian From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christian Zigotzky Date: Sun, 14 Jun 2020 14:52:10 +0000 Subject: Re: PowerPC KVM-PR issue Message-Id: List-Id: References: <067BBAB3-19B6-42C6-AA9F-B9F14314255C@xenosoft.de> <014e1268-dcce-61a3-8bcd-a06c43e0dfaf@csgroup.eu> <7bf97562-3c6d-de73-6dbd-ccca275edc7b@xenosoft.de> <87tuznq89p.fsf@linux.ibm.com>

<7e859f68-9455-f98f-1fa3-071619fa1731@xenosoft.de> <54082b17-31bb-f529-2e9e-b84c5a5aa9ec@xenosoft.de> <1592139127.g2951cl0h6.astroid@bobo.none> In-Reply-To: <1592139127.g2951cl0h6.astroid@bobo.none> MIME-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: quoted-printable To: Nicholas Piggin , "kvm-ppc@vger.kernel.org" , linuxppc-dev Cc: Darren Stevens , "R.T.Dickinson" , Christian Zigotzky On 14 June 2020 at 02:53 pm, Nicholas Piggin wrote: > Excerpts from Christian Zigotzky's message of June 12, 2020 11:01 pm: >> On 11 June 2020 at 04:47 pm, Christian Zigotzky wrote: >>> On 10 June 2020 at 01:23 pm, Christian Zigotzky wrote: >>>> On 10 June 2020 at 11:06 am, Christian Zigotzky wrote: >>>>> On 10 June 2020 at 00:18 am, Christian Zigotzky wrote: >>>>>> Hello, >>>>>> >>>>>> KVM-PR doesn't work anymore on my Nemo board [1]. I figured out >>>>>> that the Git kernels and the kernel 5.7 are affected. >>>>>> >>>>>> Error message: Fienix kernel: kvmppc_exit_pr_progint: emulation at >>>>>> 700 failed (00000000) >>>>>> >>>>>> I can boot virtual QEMU PowerPC machines with KVM-PR with the >>>>>> kernel 5.6 without any problems on my Nemo board. >>>>>> >>>>>> I tested it with QEMU 2.5.0 and QEMU 5.0.0 today. >>>>>> >>>>>> Could you please check KVM-PR on your PowerPC machine? >>>>>> >>>>>> Thanks, >>>>>> Christian >>>>>> >>>>>> [1] https://en.wikipedia.org/wiki/AmigaOne_X1000 >>>>> I figured out that the PowerPC updates 5.7-1 [1] are responsible for >>>>> the KVM-PR issue. Please test KVM-PR on your PowerPC machines and >>>>> check the PowerPC updates 5.7-1 [1]. >>>>> >>>>> Thanks >>>>> >>>>> [1] >>>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/co= mmit/?id=D38c07afc356ddebaa3ed8ecb3f553340e05c969 >>>>> >>>>> >>>> I tested the latest Git kernel with Mac-on-Linux/KVM-PR today. >>>> Unfortunately I can't use KVM-PR with MoL anymore because of this >>>> issue (see screenshots [1]). Please check the PowerPC updates 5.7-1. >>>> >>>> Thanks >>>> >>>> [1] >>>> - >>>> https://i.pinimg.com/originals/0c/b3/64/0cb364a40241fa2b7f297d4272bbb8= b7.png >>>> - >>>> https://i.pinimg.com/originals/9a/61/d1/9a61d170b1c9f514f7a78a3014ffd1= 8f.png >>>> >>> Hi All, >>> >>> I bisected today because of the KVM-PR issue. >>> >>> Result: >>> >>> 9600f261acaaabd476d7833cec2dd20f2919f1a0 is the first bad commit >>> commit 9600f261acaaabd476d7833cec2dd20f2919f1a0 >>> Author: Nicholas Piggin >>> Date:=C2=A0=C2=A0 Wed Feb 26 03:35:21 2020 +1000 >>> >>> =C2=A0=C2=A0=C2=A0 powerpc/64s/exception: Move KVM test to common code >>> >>> =C2=A0=C2=A0=C2=A0 This allows more code to be moved out of unrelocate= d regions. The >>> =C2=A0=C2=A0=C2=A0 system call KVMTEST is changed to be open-coded and= remain in the >>> =C2=A0=C2=A0=C2=A0 tramp area to avoid having to move it to entry_64.S= . The custom >>> nature >>> =C2=A0=C2=A0=C2=A0 of the system call entry code means the hcall case = can be made more >>> =C2=A0=C2=A0=C2=A0 streamlined than regular interrupt handlers. >>> >>> =C2=A0=C2=A0=C2=A0 mpe: Incorporate fix from Nick: >>> >>> =C2=A0=C2=A0=C2=A0 Moving KVM test to the common entry code missed the= case of HMI and >>> =C2=A0=C2=A0=C2=A0 MCE, which do not do __GEN_COMMON_ENTRY (because th= ey don't want to >>> =C2=A0=C2=A0=C2=A0 switch to virt mode). >>> >>> =C2=A0=C2=A0=C2=A0 This means a MCE or HMI exception that is taken whi= le KVM is >>> running a >>> =C2=A0=C2=A0=C2=A0 guest context will not be switched out of that cont= ext, and KVM won't >>> =C2=A0=C2=A0=C2=A0 be notified. Found by running sigfuz in guest with = patched host on >>> =C2=A0=C2=A0=C2=A0 POWER9 DD2.3, which causes some TM related HMI inte= rrupts (which are >>> =C2=A0=C2=A0=C2=A0 expected and supposed to be handled by KVM). >>> >>> =C2=A0=C2=A0=C2=A0 This fix adds a __GEN_REALMODE_COMMON_ENTRY for tho= se handlers to add >>> =C2=A0=C2=A0=C2=A0 the KVM test. This makes them look a little more li= ke other handlers >>> =C2=A0=C2=A0=C2=A0 that all use __GEN_COMMON_ENTRY. >>> >>> =C2=A0=C2=A0=C2=A0 Signed-off-by: Nicholas Piggin >>> =C2=A0=C2=A0=C2=A0 Signed-off-by: Michael Ellerman >>> =C2=A0=C2=A0=C2=A0 Link: >>> https://lore.kernel.org/r/20200225173541.1549955-13-npiggin@gmail.com >>> >>> :040000 040000 ec21cec22d165f8696d69532734cb2985d532cb0 >>> 87dd49a9cd7202ec79350e8ca26cea01f1dbd93d M=C2=A0=C2=A0=C2=A0 arch >>> >>> ----- >>> >>> The following commit is the problem: powerpc/64s/exception: Move KVM >>> test to common code [1] >>> >>> These changes were included in the PowerPC updates 5.7-1. [2] >>> >>> Another test: >>> >>> git checkout d38c07afc356ddebaa3ed8ecb3f553340e05c969 (PowerPC updates >>> 5.7-1 [2] ) -> KVM-PR doesn't work. >>> >>> After that: git revert d38c07afc356ddebaa3ed8ecb3f553340e05c969 -m 1 >>> -> KVM-PR works. >>> >>> Could you please check the first bad commit? [1] >>> >>> Thanks, >>> Christian >>> >>> >>> [1] >>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/comm= it/?id=9600f261acaaabd476d7833cec2dd20f2919f1a0 >>> [2] >>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/comm= it/?id=D38c07afc356ddebaa3ed8ecb3f553340e05c969 >> Hi All, >> >> I tried to revert the __GEN_REALMODE_COMMON_ENTRY fix for the latest Git >> kernel and for the stable kernel 5.7.2 but without any success. There >> was lot of restructuring work during the kernel 5.7 development time in >> the PowerPC area so it isn't possible reactivate the old code. That >> means we have lost the whole KVM-PR support. I also reported this issue >> to Alexander Graf two days ago. He wrote: "Howdy :). It looks pretty >> broken. Have you ever made a bisect to see where the problem comes from?" >> >> Please check the KVM-PR code. > Does this patch fix it for you? > > The CTR register reload in the KVM interrupt path used the wrong save > area for SLB (and NMI) interrupts. > > Fixes: 9600f261acaaa ("powerpc/64s/exception: Move KVM test to common cod= e") > Reported-by: Christian Zigotzky > Signed-off-by: Nicholas Piggin > --- > arch/powerpc/kernel/exceptions-64s.S | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/e= xceptions-64s.S > index e70ebb5c318c..fa080694e581 100644 > --- a/arch/powerpc/kernel/exceptions-64s.S > +++ b/arch/powerpc/kernel/exceptions-64s.S > @@ -270,7 +270,7 @@ BEGIN_FTR_SECTION > END_FTR_SECTION_IFSET(CPU_FTR_CFAR) > .endif > =20 > - ld r10,PACA_EXGEN+EX_CTR(r13) > + ld r10,IAREA+EX_CTR(r13) > mtctr r10 > BEGIN_FTR_SECTION > ld r10,IAREA+EX_PPR(r13) > @@ -298,7 +298,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) > =20 > .if IKVM_SKIP > 89: mtocrf 0x80,r9 > - ld r10,PACA_EXGEN+EX_CTR(r13) > + ld r10,IAREA+EX_CTR(r13) > mtctr r10 > ld r9,IAREA+EX_R9(r13) > ld r10,IAREA+EX_R10(r13) Many thanks for the fix! I will test it with the RC1 tomorrow. -- Christian