get_runtime_offset returns the offset that needs to be added onto code addresses to arrive at the runtime address. This is 0 after code relocation and the function calculates it by keeping a reference to _text and substituting it from the actual _text address, which is found out in a position-independent manner. For enabling barebox PBL text section to be mappable W^X, we need to avoid relocation entries within code, so let's move the runtime offset into the data section, which is always mapped writable. As ldr has only a 4K range for label references, we switch to ldr_l, which has a 4G range. Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> --- arch/arm/lib64/runtime-offset.S | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/arm/lib64/runtime-offset.S b/arch/arm/lib64/runtime-offset.S index 822e323c142e..b10c104b4dd0 100644 --- a/arch/arm/lib64/runtime-offset.S +++ b/arch/arm/lib64/runtime-offset.S @@ -11,10 +11,12 @@ */ ENTRY(get_runtime_offset) adr x0, _text - ldr x1, linkadr + ldr_l x1, linkadr subs x0, x0, x1 ret +ENDPROC(get_runtime_offset) +.section ".data.runtime_offset","a" .align 3 linkadr: /* @@ -24,4 +26,3 @@ linkadr: * use _text here since that is 0x0 and is correct without relocation. */ .quad _text -ENDPROC(get_runtime_offset) -- 2.39.2
