diff options
| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2015-10-29 15:07:25 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2015-10-29 16:10:58 +0000 |
| commit | 73effccb9196ccc0241c3fb51dfd8de1d14ae8ed (patch) | |
| tree | b5cc57b7c2930d53923b1edc704de3ff74df6231 | |
| parent | 9702970c7bd3e2d6fecb642a190269131d4ac16c (diff) | |
arm64/efi: do not assume DRAM base is aligned to 2 MB
The current arm64 Image relocation code in the UEFI stub assumes that
the dram_base argument it receives is always a multiple of 2 MB. In
reality, it is simply the lowest start address of all RAM entries in
the UEFI memory map, which means it could be any multiple of 4 KB.
Since the arm64 kernel Image needs to reside TEXT_OFFSET bytes beyond
a 2 MB aligned base, or it will fail to boot, make sure we round dram_base
to 2 MB before using it to calculate the relocation address.
Fixes: e38457c361b30c5a ("arm64: efi: prefer AllocatePages() over efi_low_alloc() for vmlinux")
Reported-by: Timur Tabi <timur@codeaurora.org>
Tested-by: Timur Tabi <timur@codeaurora.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
| -rw-r--r-- | arch/arm64/kernel/efi-stub.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/arch/arm64/kernel/efi-stub.c b/arch/arm64/kernel/efi-stub.c index 816120ece6bc..78dfbd34b6bf 100644 --- a/arch/arm64/kernel/efi-stub.c +++ b/arch/arm64/kernel/efi-stub.c @@ -25,10 +25,20 @@ efi_status_t __init handle_kernel_image(efi_system_table_t *sys_table_arg, unsigned long kernel_size, kernel_memsize = 0; unsigned long nr_pages; void *old_image_addr = (void *)*image_addr; + unsigned long preferred_offset; + + /* + * The preferred offset of the kernel Image is TEXT_OFFSET bytes beyond + * a 2 MB aligned base, which itself may be lower than dram_base, as + * long as the resulting offset equals or exceeds it. + */ + preferred_offset = round_down(dram_base, SZ_2M) + TEXT_OFFSET; + if (preferred_offset < dram_base) + preferred_offset += SZ_2M; /* Relocate the image, if required. */ kernel_size = _edata - _text; - if (*image_addr != (dram_base + TEXT_OFFSET)) { + if (*image_addr != preferred_offset) { kernel_memsize = kernel_size + (_end - _edata); /* @@ -42,7 +52,7 @@ efi_status_t __init handle_kernel_image(efi_system_table_t *sys_table_arg, * Mustang), we can still place the kernel at the address * 'dram_base + TEXT_OFFSET'. */ - *image_addr = *reserve_addr = dram_base + TEXT_OFFSET; + *image_addr = *reserve_addr = preferred_offset; nr_pages = round_up(kernel_memsize, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE; status = efi_call_early(allocate_pages, EFI_ALLOCATE_ADDRESS, |