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=-0.7 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 16077C47092 for ; Wed, 2 Jun 2021 08:53:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E2A0E613D0 for ; Wed, 2 Jun 2021 08:53:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232889AbhFBIzh (ORCPT ); Wed, 2 Jun 2021 04:55:37 -0400 Received: from mga01.intel.com ([192.55.52.88]:48991 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229959AbhFBIzf (ORCPT ); Wed, 2 Jun 2021 04:55:35 -0400 IronPort-SDR: URL9a4AKTO1OP3yOojfWTja4CoK/uiMcrgYdVfNAFXJeS0uMt4NK7jEnvDRoU6uYNyzCy81vR5 UjBT+BRRqinQ== X-IronPort-AV: E=McAfee;i="6200,9189,10002"; a="225028228" X-IronPort-AV: E=Sophos;i="5.83,241,1616482800"; d="scan'208";a="225028228" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Jun 2021 01:53:51 -0700 IronPort-SDR: EGZAyGBJeu3qSCpxms65HELWLfWbZoR8DsCYmC9dwVEC+azcYFwkUiZetwahkG9yOU+jn+evtO 4djqrXWJuD9g== X-IronPort-AV: E=Sophos;i="5.83,241,1616482800"; d="scan'208";a="411548964" Received: from smile.fi.intel.com (HELO smile) ([10.237.68.40]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Jun 2021 01:53:49 -0700 Received: from andy by smile with local (Exim 4.94) (envelope-from ) id 1loMdG-00GfBX-Re; Wed, 02 Jun 2021 11:53:46 +0300 Date: Wed, 2 Jun 2021 11:53:46 +0300 From: Andy Shevchenko To: Ard Biesheuvel , Javier =?iso-8859-1?B?VGnh?= Cc: "Eric W. Biederman" , Dave Young , linux-efi , Matt Fleming , Kexec Mailing List , Linux Kernel Mailing List , Mika Westerberg , Jean Delvare Subject: Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel Message-ID: References: <20161215122856.7d24b7a8@endymion> <20161216023213.GA4505@dhcp-128-65.nay.redhat.com> <1481890738.9552.70.camel@linux.intel.com> <20161216143330.69e9c8ee@endymion> <20161217105721.GB6922@dhcp-128-65.nay.redhat.com> <20200120121927.GJ32742@smile.fi.intel.com> <87a76i9ksr.fsf@x220.int.ebiederm.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Fixed Ard's address On Wed, Jun 02, 2021 at 11:37:29AM +0300, Andy Shevchenko wrote: > On Tue, Jan 21, 2020 at 12:18:03AM +0100, Ard Biesheuvel wrote: > > On Mon, 20 Jan 2020 at 23:31, Andy Shevchenko wrote: > > > > > > On Mon, Jan 20, 2020 at 9:28 PM Eric W. Biederman wrote: > > > > Andy Shevchenko writes: > > > > > On Sat, Dec 17, 2016 at 06:57:21PM +0800, Dave Young wrote: > > > > >> Ccing efi people. > > > > >> > > > > >> On 12/16/16 at 02:33pm, Jean Delvare wrote: > > > > >> > On Fri, 16 Dec 2016 14:18:58 +0200, Andy Shevchenko wrote: > > > > >> > > On Fri, 2016-12-16 at 10:32 +0800, Dave Young wrote: > > > > >> > > > On 12/15/16 at 12:28pm, Jean Delvare wrote: > > > > >> > > > > I am no kexec expert but this confuses me. Shouldn't the second > > > > >> > > > > kernel have access to the EFI systab as the first kernel does? It > > > > >> > > > > includes many more pointers than just ACPI and DMI tables, and it > > > > >> > > > > would seem inconvenient to have to pass all these addresses > > > > >> > > > > individually explicitly. > > > > >> > > > > > > > >> > > > Yes, in modern linux kernel, kexec has the support for EFI, I think it > > > > >> > > > should work naturally at least in x86_64. > > > > >> > > > > > > >> > > Thanks for this good news! > > > > >> > > > > > > >> > > Unfortunately Intel Galileo is 32-bit platform. > > > > >> > > > > > >> > If it was done for X86_64 then maybe it can be generalized to X86? > > > > >> > > > > >> For X86_64, we have a new way for efi runtime memmory mapping, in i386 > > > > >> code it still use old ioremap way. It is impossible to use same way as > > > > >> the X86_64 since the virtual address space is limited. > > > > >> > > > > >> But maybe for 32bit, kexec kernel can run in physical mode, but I'm not > > > > >> sure, I would suggest Andy to do a test first with efi=noruntime for > > > > >> kexec 2nd kernel. > > > > > > > > > > Guys, it was quite a long no hear from you. As I told you the proposed work > > > > > around didn't help. Today I found that Microsoft Surface 3 also affected > > > > > by this. > > > > > > > > > > Can we apply these patches for now until you will find better > > > > > solution? > > > > > > > > Not a chance. The patches don't apply to any kernel in the git history. > > > > > > > > Which may be part of your problem. You are or at least were running > > > > with code that has not been merged upstream. > > > > > > It's done against linux-next. > > > Applied clearly. (Not the version in this more than yearly old series > > > of course, that's why I told I can resend) > > > > > > > > P.S. I may resend them rebased on recent vanilla. > > > > > > > > Second. I looked at your test results and they don't directly make > > > > sense. dmidecode bypasses the kernel completely or it did last time > > > > I looked so I don't know why you would be using that to test if > > > > something in the kernel is working. > > > > > > > > However dmidecode failing suggests that the actual problem is something > > > > in the first kernel is stomping the dmi tables. > > > > > > See below. > > > > > > > Adding a command line option won't fix stomped tables. > > > > > > It provides a mechanism, which seems to be absent, to the second > > > kernel to know where to look for SMBIOS tables. > > > > > > > So what I would suggest is: > > > > a) Verify that dmidecode works before kexec. > > > > > > Yes, it does. > > > > > > > b) Test to see if dmidecode works after kexec. > > > > > > No, it doesn't. > > > > > > > c) Once (a) shows that dmidecode works and (b) shows that dmidecode > > > > fails figure out what is stomping your dmi tables during or before > > > > kexec and that is what should get fixed. > > > > > > The problem here as I can see it that EFI and kexec protocols are not > > > friendly to each other. > > > I'm not an expert in either. That's why I'm asking for possible > > > solutions. And this needs to be done in kernel to allow drivers to > > > work. > > > > > > Does the > > > > > > commit 4996c02306a25def1d352ec8e8f48895bbc7dea9 > > > Author: Takao Indoh > > > Date: Thu Jul 14 18:05:21 2011 -0400 > > > > > > ACPI: introduce "acpi_rsdp=" parameter for kdump > > > > > > description shed a light on this? > > > > > > > Now using a non-efi method of dmi detection relies on the > > > > tables being between 0xF0000 and 0x10000. AKA the last 64K > > > > of the first 1MiB of memory. You might check to see if your > > > > dmi tables are in that address range. > > > > > > # dmidecode --no-sysfs > > > # dmidecode 3.2 > > > Scanning /dev/mem for entry point. > > > # No SMBIOS nor DMI entry point found, sorry. > > > > > > === with patch applied === > > > # dmidecode > > > ... > > > Release Date: 03/10/2015 > > > ... > > > > > > > > > > > Otherwise I suspect the good solution is to give efi it's own page > > > > tables in the kernel and switch to it whenever efi functions are called. > > > > > > > > > > > But on 32bit the Linux kernel has historically been just fine directly > > > > accessing the hardware, and ignoring efi and all of the other BIOS's. > > > > > > It seems not only for 32-bit Linux kernel anymore. MS Surface 3 runs > > > 64-bit code. > > > > > > > So if that doesn't work on Intel Galileo that is probably a firmware > > > > problem. > > > > > > It's not only about Galileo anymore. > > > > > > > Looking at the x86 kexec EFI code, it seems that it has special > > handling for the legacy SMBIOS table address, but not for the SMBIOS3 > > table address, which was introduced to accommodate SMBIOS tables > > living in memory that is not 32-bit addressable. > > > > Could anyone check whether these systems provide SMBIOS 3.0 tables, > > and whether their address gets virtually remapped at ExitBootServices? > > Can you tell how to do this and I will try to get information? > > -- > With Best Regards, > Andy Shevchenko > > -- With Best Regards, Andy Shevchenko From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mga05.intel.com ([192.55.52.43]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1loMdM-002nOp-VS for kexec@lists.infradead.org; Wed, 02 Jun 2021 08:53:59 +0000 Date: Wed, 2 Jun 2021 11:53:46 +0300 From: Andy Shevchenko Subject: Re: [PATCH v1 2/2] firmware: dmi_scan: Pass dmi_entry_point to kexec'ed kernel Message-ID: References: <20161215122856.7d24b7a8@endymion> <20161216023213.GA4505@dhcp-128-65.nay.redhat.com> <1481890738.9552.70.camel@linux.intel.com> <20161216143330.69e9c8ee@endymion> <20161217105721.GB6922@dhcp-128-65.nay.redhat.com> <20200120121927.GJ32742@smile.fi.intel.com> <87a76i9ksr.fsf@x220.int.ebiederm.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: 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: Ard Biesheuvel , Javier =?iso-8859-1?B?VGnh?= Cc: "Eric W. Biederman" , Dave Young , linux-efi , Matt Fleming , Kexec Mailing List , Linux Kernel Mailing List , Mika Westerberg , Jean Delvare Fixed Ard's address On Wed, Jun 02, 2021 at 11:37:29AM +0300, Andy Shevchenko wrote: > On Tue, Jan 21, 2020 at 12:18:03AM +0100, Ard Biesheuvel wrote: > > On Mon, 20 Jan 2020 at 23:31, Andy Shevchenko wrote: > > > > > > On Mon, Jan 20, 2020 at 9:28 PM Eric W. Biederman wrote: > > > > Andy Shevchenko writes: > > > > > On Sat, Dec 17, 2016 at 06:57:21PM +0800, Dave Young wrote: > > > > >> Ccing efi people. > > > > >> > > > > >> On 12/16/16 at 02:33pm, Jean Delvare wrote: > > > > >> > On Fri, 16 Dec 2016 14:18:58 +0200, Andy Shevchenko wrote: > > > > >> > > On Fri, 2016-12-16 at 10:32 +0800, Dave Young wrote: > > > > >> > > > On 12/15/16 at 12:28pm, Jean Delvare wrote: > > > > >> > > > > I am no kexec expert but this confuses me. Shouldn't the second > > > > >> > > > > kernel have access to the EFI systab as the first kernel does? It > > > > >> > > > > includes many more pointers than just ACPI and DMI tables, and it > > > > >> > > > > would seem inconvenient to have to pass all these addresses > > > > >> > > > > individually explicitly. > > > > >> > > > > > > > >> > > > Yes, in modern linux kernel, kexec has the support for EFI, I think it > > > > >> > > > should work naturally at least in x86_64. > > > > >> > > > > > > >> > > Thanks for this good news! > > > > >> > > > > > > >> > > Unfortunately Intel Galileo is 32-bit platform. > > > > >> > > > > > >> > If it was done for X86_64 then maybe it can be generalized to X86? > > > > >> > > > > >> For X86_64, we have a new way for efi runtime memmory mapping, in i386 > > > > >> code it still use old ioremap way. It is impossible to use same way as > > > > >> the X86_64 since the virtual address space is limited. > > > > >> > > > > >> But maybe for 32bit, kexec kernel can run in physical mode, but I'm not > > > > >> sure, I would suggest Andy to do a test first with efi=noruntime for > > > > >> kexec 2nd kernel. > > > > > > > > > > Guys, it was quite a long no hear from you. As I told you the proposed work > > > > > around didn't help. Today I found that Microsoft Surface 3 also affected > > > > > by this. > > > > > > > > > > Can we apply these patches for now until you will find better > > > > > solution? > > > > > > > > Not a chance. The patches don't apply to any kernel in the git history. > > > > > > > > Which may be part of your problem. You are or at least were running > > > > with code that has not been merged upstream. > > > > > > It's done against linux-next. > > > Applied clearly. (Not the version in this more than yearly old series > > > of course, that's why I told I can resend) > > > > > > > > P.S. I may resend them rebased on recent vanilla. > > > > > > > > Second. I looked at your test results and they don't directly make > > > > sense. dmidecode bypasses the kernel completely or it did last time > > > > I looked so I don't know why you would be using that to test if > > > > something in the kernel is working. > > > > > > > > However dmidecode failing suggests that the actual problem is something > > > > in the first kernel is stomping the dmi tables. > > > > > > See below. > > > > > > > Adding a command line option won't fix stomped tables. > > > > > > It provides a mechanism, which seems to be absent, to the second > > > kernel to know where to look for SMBIOS tables. > > > > > > > So what I would suggest is: > > > > a) Verify that dmidecode works before kexec. > > > > > > Yes, it does. > > > > > > > b) Test to see if dmidecode works after kexec. > > > > > > No, it doesn't. > > > > > > > c) Once (a) shows that dmidecode works and (b) shows that dmidecode > > > > fails figure out what is stomping your dmi tables during or before > > > > kexec and that is what should get fixed. > > > > > > The problem here as I can see it that EFI and kexec protocols are not > > > friendly to each other. > > > I'm not an expert in either. That's why I'm asking for possible > > > solutions. And this needs to be done in kernel to allow drivers to > > > work. > > > > > > Does the > > > > > > commit 4996c02306a25def1d352ec8e8f48895bbc7dea9 > > > Author: Takao Indoh > > > Date: Thu Jul 14 18:05:21 2011 -0400 > > > > > > ACPI: introduce "acpi_rsdp=" parameter for kdump > > > > > > description shed a light on this? > > > > > > > Now using a non-efi method of dmi detection relies on the > > > > tables being between 0xF0000 and 0x10000. AKA the last 64K > > > > of the first 1MiB of memory. You might check to see if your > > > > dmi tables are in that address range. > > > > > > # dmidecode --no-sysfs > > > # dmidecode 3.2 > > > Scanning /dev/mem for entry point. > > > # No SMBIOS nor DMI entry point found, sorry. > > > > > > === with patch applied === > > > # dmidecode > > > ... > > > Release Date: 03/10/2015 > > > ... > > > > > > > > > > > Otherwise I suspect the good solution is to give efi it's own page > > > > tables in the kernel and switch to it whenever efi functions are called. > > > > > > > > > > > But on 32bit the Linux kernel has historically been just fine directly > > > > accessing the hardware, and ignoring efi and all of the other BIOS's. > > > > > > It seems not only for 32-bit Linux kernel anymore. MS Surface 3 runs > > > 64-bit code. > > > > > > > So if that doesn't work on Intel Galileo that is probably a firmware > > > > problem. > > > > > > It's not only about Galileo anymore. > > > > > > > Looking at the x86 kexec EFI code, it seems that it has special > > handling for the legacy SMBIOS table address, but not for the SMBIOS3 > > table address, which was introduced to accommodate SMBIOS tables > > living in memory that is not 32-bit addressable. > > > > Could anyone check whether these systems provide SMBIOS 3.0 tables, > > and whether their address gets virtually remapped at ExitBootServices? > > Can you tell how to do this and I will try to get information? > > -- > With Best Regards, > Andy Shevchenko > > -- With Best Regards, Andy Shevchenko _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec