On 10/28/2015 01:08 PM, Mark Rutland wrote:
arm64: efi: ensure kernel is loaded at correct address The kernel image needs to be loaded text_offset_bytes from a 2M-aligned base, per Documentation/arm64/booting.txt. If loaded at the wrong offset modulo 2M, __create_page_tables will create incorrect page tables. The EFI stub implicitly assumes that dram_base (i.e. the lowest address with a EFI_MEMORY_WB attribute) is 2M-aligned, and tries to load the kernel at dram_base + TEXT_OFFSET. If dram_base is not 2M-aligned, the kernel will be loaded at the wrong offset from 2M.
Thanks, I'll use that. I messed up a couple other things, so I need to send out a v3 anyway.
- *image_addr = *reserve_addr = dram_base + TEXT_OFFSET; + *image_addr = *reserve_addr = + round_up(dram_base, SZ_2M) + TEXT_OFFSET;We also need to fix the test for whether we need to relocate the kernel: (*image_addr != (dram_base + TEXT_OFFSET)). When dram_base is not 2M aligned, that is broken, and it's been broken since it was introduced in commit 3c7f255039a2ad6e ("arm64: efi: add EFI stub") in v3.16. It's a bit hideous to fix the general case, though, it seems.
Um, so I should I do something more in my v3 patch, or is this a change for a different patch?
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