On Wed, Oct 30, 2019 at 1:14 PM Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> wrote: > > On Wed, 30 Oct 2019 at 08:36, Prabhakar Kushwaha > <prabhakar.pkin@xxxxxxxxx> wrote: > > > > On Wed, Oct 30, 2019 at 12:43 PM Ard Biesheuvel > > <ard.biesheuvel@xxxxxxxxxx> wrote: > > > > > > On Tue, 29 Oct 2019 at 18:17, Prabhakar Kushwaha > > > <prabhakar.pkin@xxxxxxxxx> wrote: > > > > > > > > Hi All, > > > > > > > > I am working on Ubuntu-18.04 with UEFI on ARM64(64 bit) platform. The > > > > UEFI used is having ACPI tables. > > > > > > > > I am trying to understand where and how /sys/firmware/fdt is getting > > > > created. is it created by UEFI or grub and passed to Linux? > > > > > > > > > > Neither. It is created by Linux itself. > > > > > > > > > > > > > Thanks Ard, > > > > Can you please point me the code where it is getting created. > > I want to add below in /sys/firmware/fdt. > > > > #size-cells = <0x02>; > > #address-cells = <0x02>; > > > > Actually, in your case it is GRUB not the kernel that creates the FDT. > It does this to pass the initrd information. > > So if you want to add these properties, you should add them there. > > Can you explain why doing this is necessary? I am trying to test kexec -p (kdump feature) on CentOS-release 7.7.1908 and Ubuntu-18.04 distributions. "kexec -p" command show error on Ubuntu. While no error on CentOS CentOS: $ kexec -p /boot/vmlinuz-`uname -r` --initrd=/boot/initramfs-`uname -r`.img --reuse-cmdline $ ==> No error Ubuntu $ kexec -p /boot/vmlinuz-`uname -r` --initrd=/boot/initrd.img-`uname -r` --reuse-cmdline $ kexec: elfcorehdr doesn't fit cells-size. $ kexec: setup_2nd_dtb failed. $ kexec: load failed. $ Cannot load /boot/vmlinuz-5.4.0-rc4+ Note: Both CentOS and Ubuntu has Linux-5.4-rc4 tag. When i debugged further reason for Ubuntu error is due to address-cells and size-cells as "1" log from kexec tool :- load_crashdump_segments: elfcorehdr 0x7f7cbfc000-0x7f7cbff7ff read_1st_dtb: found name =dtb_sys /sys/firmware/fdt get_cells_size: #address-cells:1 #size-cells:1 On CentOS both values are "2". log from kexec tool :- load_crashdump_segments: elfcorehdr 0xbf98bf0000-0xbf98bf33ff read_1st_dtb: found nmae=dtb_sys /sys/firmware/fdt get_cells_size: #address-cells:2 #size-cells:2 Note: Kexec tool read values from /sys/firmware/fdt. I am trying to figure out why 2 distributions showing different values. --pk _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec