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. BTW, I am no longer at HP, so <khalid.aziz at hp.com> is no longer valid. <khalid at gonehiking.org> is my permanent personal email address. -- Khalid
