From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TQ7SJ-0007Jr-M3 for kexec@lists.infradead.org; Mon, 22 Oct 2012 02:09:29 +0000 Message-ID: <5084A9FA.1090403@redhat.com> Date: Mon, 22 Oct 2012 10:05:46 +0800 From: Dave Young MIME-Version: 1.0 Subject: Re: [PATCH]kdump: pass noefi and acpi_rsdp= to 2nd kernel References: <20120905054445.GA6370@dhcp-16-143.nay.redhat.com> <5047DBA9.8030000@hp.com> <504815EB.9000701@redhat.com> <5048E40E.7040003@hp.com> <5049B6AD.9000304@redhat.com> <504FF4DB.6030601@redhat.com> <507F7394.5020501@redhat.com> <1350572394.3894.18.camel@rhapsody> In-Reply-To: <1350572394.3894.18.camel@rhapsody> 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-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Khalid Aziz Cc: horms@verge.net.au, kexec@lists.infradead.org, vgoyal@redhat.com On 10/18/2012 10:59 PM, Khalid Aziz wrote: > On Thu, 2012-10-18 at 11:12 +0800, Dave Young wrote: >> On 09/12/2012 10:35 AM, Dave Young wrote: >> >>> On 09/07/2012 04:56 PM, Dave Young wrote: >>>> >>>> I did some digging about the efi boot kdump in slackware with kernel >>>> from latest linus tree. I'm surprise that kdump works even without these >>>> "noefi" and "acpi_rsdp=" >>>> >>>> With fedora 17 3.4.3 kernel passing "acpi_rsdp=" is enough for kdump >>>> kernel booting. >>>> >>>> Actually in x86 setup code if bootloader do not pass correct efi_info in >>>> boot_params efi_enabled will be set to 0 automaticlly. >>>> >>>> So as for this patch 'noefi' is not needed. >>>> >>>> I will do more testing to see why linus tree works without "acpi_rsdp=" >>>> >>> >>> There's probably some efi changes between 3.4.3 - 3.6.0-rc4 cause this >>> works. I have not got time to bisect it. >> >> >> During recent test, I found I mistakenly used wrong kernel config >> without CONFIG_EFI in 1st kernel for testing. acpi_rsdp= is still needed. >> >> Just resent the v2 patch, please help to review. >> > > Hi Dave, > > I suspect EFI based systems with Compatibility Support Module (CSM) are > still not going to need this, but I can see native EFI systems with no > CSM needing this. I have reviewed your patch. Good to know, I have no CSM machine to test. Since Simon has applied the patch, I think I can improve this issue later If I can find a machine with CSM. > > BTW, I am no longer at HP, so is no longer valid. > is my permanent personal email address. Thanks for reminding. > > -- > Khalid > > > _______________________________________________ > kexec mailing list > kexec@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/kexec -- Thanks Dave _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec