On Thu, Apr 4, 2019 at 3:25 PM Dave Young <dyoung@xxxxxxxxxx> wrote: > > Hello Kairui > On 03/28/19 at 05:49pm, Kairui Song wrote: > > Since kernel commit e6e094e053af75 ("x86/acpi, x86/boot: Take RSDP address > > from boot params if available"), kernel accept a acpi_rsdp_addr param in > > boot_params. Sync the x86_linux_param_header to support this param. > > > > And previously we are already appending 'acpi_rsdp=' command line only for > > loading crash kernel on EFI systems, it will be better to try to set the > > boot param for any kernel get loaded, to help the kernel finding the > > RSDP value more stably. Otherwise if the user decide to disable EFI > > service in second kernel, it will fail to boot. > > > > There is no better way to find the RSDP address from legacy BIOS > > interface rather than scanning the memory region and search for it, > > which will always be done by the kernel as a fallback, so we only > > look for RSDP in previous boot params, cmdline and EFI firmware. > > It would be good to always pass acpi_rsdp= kernel cmdline in case > efi=old_map. (or maybe efi=noruntime as well, but I did not remember > the behavior of noruntime now), no matter kexec or kdump.. > > And if you want, maybe fill the boot_params instead of passing cmdline > for new kernel which supports the new boot_param field. > > Split the patch to small patches would be better. > > Thanks > Dave Thanks for the review! I'll update in V2 accordingly. -- Best Regards, Kairui Song _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec