lkml.org 
[lkml]   [2023]   [Mar]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] efi/loongarch: Reintroduce efi_relocate_kernel() to relocate kernel
From
Date
Hi, Huacai

On 03/01/2023 05:30 PM, Huacai Chen wrote:
> Hi, Youling,
>
> On Wed, Mar 1, 2023 at 5:21 PM Youling Tang <tangyouling@loongson.cn> wrote:
>>
>> Hi, Huacai
>>
>> On 03/01/2023 04:55 PM, Huacai Chen wrote:
>>> Since Linux-6.3, LoongArch supports PIE kernel now, so let's reintroduce
>>> efi_relocate_kernel() to relocate the core kernel.
>>
>> If we strongly rely on the PIE feature after the modification, we need
>> to modify it as follows,
> There is no strong rely, efi_relocate_kernel() can also handle the
> non-PIE kernel.

IMHO, if EFI_KIMG_PREFERRED_ADDRESS is no longer defined as
`PHYSADDR(VMLINUX_LOAD_ADDRESS)` (physical link address), we need to
relocate through the RELOCATABLE function, so it is recommended to
select RELOCATABLE if EFI_STUB is enabled

Youling.
>
> Huacai
>>
>> --- a/arch/loongarch/Kconfig
>> +++ b/arch/loongarch/Kconfig
>> @@ -137,6 +137,7 @@ config LOONGARCH
>> select PCI_MSI_ARCH_FALLBACKS
>> select PCI_QUIRKS
>> select PERF_USE_VMALLOC
>> + select RELOCATABLE
>> select RTC_LIB
>> select SMP
>> select SPARSE_IRQ
>>
>> or:
>>
>> --- a/arch/loongarch/Kconfig
>> +++ b/arch/loongarch/Kconfig
>> @@ -360,6 +360,7 @@ config EFI_STUB
>> default y
>> depends on EFI
>> select EFI_GENERIC_STUB
>> + select RELOCATABLE
>> help
>>
>> Youling.
>>
>>>
>>> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
>>> ---
>>> drivers/firmware/efi/libstub/loongarch-stub.c | 24 ++++++-------------
>>> 1 file changed, 7 insertions(+), 17 deletions(-)
>>>
>>> diff --git a/drivers/firmware/efi/libstub/loongarch-stub.c b/drivers/firmware/efi/libstub/loongarch-stub.c
>>> index eee7ed43cdfb..72c71ae201f0 100644
>>> --- a/drivers/firmware/efi/libstub/loongarch-stub.c
>>> +++ b/drivers/firmware/efi/libstub/loongarch-stub.c
>>> @@ -21,26 +21,16 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
>>> efi_loaded_image_t *image,
>>> efi_handle_t image_handle)
>>> {
>>> - int nr_pages = round_up(kernel_asize, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE;
>>> - efi_physical_addr_t kernel_addr = EFI_KIMG_PREFERRED_ADDRESS;
>>> efi_status_t status;
>>> + unsigned long kernel_addr = 0;
>>>
>>> - /*
>>> - * Allocate space for the kernel image at the preferred offset. This is
>>> - * the only location in memory from where we can execute the image, so
>>> - * no point in falling back to another allocation.
>>> - */
>>> - status = efi_bs_call(allocate_pages, EFI_ALLOCATE_ADDRESS,
>>> - EFI_LOADER_DATA, nr_pages, &kernel_addr);
>>> - if (status != EFI_SUCCESS)
>>> - return status;
>>> -
>>> - *image_addr = EFI_KIMG_PREFERRED_ADDRESS;
>>> - *image_size = kernel_asize;
>>> + kernel_addr = (unsigned long)&kernel_offset - kernel_offset;
>>> +
>>> + status = efi_relocate_kernel(&kernel_addr, kernel_fsize, kernel_asize,
>>> + EFI_KIMG_PREFERRED_ADDRESS, efi_get_kimg_min_align(), 0x0);
>>>
>>> - memcpy((void *)EFI_KIMG_PREFERRED_ADDRESS,
>>> - (void *)&kernel_offset - kernel_offset,
>>> - kernel_fsize);
>>> + *image_addr = kernel_addr;
>>> + *image_size = kernel_asize;
>>>
>>> return status;
>>> }
>>>
>>

\
 
 \ /
  Last update: 2023-03-27 00:39    [W:0.047 / U:0.096 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site