On 6/15/21 8:33 AM, Kunihiko Hayashi wrote:
If both POSITION_INDEPENDENT and SYS_RELOC_GD_ENV_ADDR are enabled,
wherever original env is placed anywhere, it should be relocated to
the right address.
Relocation offset gd->reloc_off is calculated with SYS_TEXT_BASE in
setup_reloc() and env address gd->env_addr is relocated by the offset in
initr_reloc_global_data().
gd->env_addr
= (orig env) + gd->reloc_off
= (orig env) + (gd->relocaddr - SYS_TEXT_BASE)
However, SYS_TEXT_BASE isn't always runtime base address when
POSITION_INDEPENDENT is enabled. So the relocated env_addr might point to
wrong address. For example, if SYS_TEXT_BASE is zero, gd->env_addr is
out of memory location and memory exception will occur.
There is a difference between linked address such as SYS_TEXT_BASE and
runtime base address. In _main, the difference is calculated as
"run-vs-link" offset. The env_addr should also be added to the offset
to fix the address.
gd->env_addr
= (orig env) + ("run-vs-link" offset) + gd->reloc_off
= (orig env) + (SYS_TEXT_BASE - _start) + (gd->relocaddr - SYS_TEXT_BASE)
= (orig env) + (gd->relocaddr - _start)
Cc: Marek Vasut <ma...@denx.de>
Signed-off-by: Kunihiko Hayashi <hayashi.kunih...@socionext.com>
Thank you for debugging and fixing this properly.
Acked-by: Marek Vasut <ma...@denx.de>
Tested-by: Marek Vasut <ma...@denx.de>
I did manage to reproduce it on RCar3, and this patch fixes the crash on
boot indeed.
Tom, it would be good to include it in this release too.
