Re: [PATCH] powerpc: Fix loading of kernel + initramfs with kexec_file_load()

From: Thiago Jung Bauermann
Date: Thu May 23 2019 - 00:46:32 EST



Dave Young <dyoung@xxxxxxxxxx> writes:

> On 05/22/19 at 07:01pm, Thiago Jung Bauermann wrote:
>> Commit b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
>> changed kexec_add_buffer() to skip searching for a memory location if
>> kexec_buf.mem is already set, and use the address that is there.
>>
>> In powerpc code we reuse a kexec_buf variable for loading both the kernel
>> and the initramfs by resetting some of the fields between those uses, but
>> not mem. This causes kexec_add_buffer() to try to load the kernel at the
>> same address where initramfs will be loaded, which is naturally rejected:
>>
>> # kexec -s -l --initrd initramfs vmlinuz
>> kexec_file_load failed: Invalid argument
>>
>> Setting the mem field before every call to kexec_add_buffer() fixes this
>> regression.
>>
>> Fixes: b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()")
>> Signed-off-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx>
>> ---
>> arch/powerpc/kernel/kexec_elf_64.c | 6 +++++-
>> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> Reviewed-by: Dave Young <dyoung@xxxxxxxxxx>

Thanks!

--
Thiago Jung Bauermann
IBM Linux Technology Center