On Sun, Jun 11, 2023 at 04:54:17PM -0700, Bo Gan wrote:
Harts need to use per-hart stack before any function call, even if that function is a simple one. When the callee uses stack for register save/ restore, especially RA, if nested call, concurrent access by multiple harts on the same stack will cause data-race.
This patch sets up SP before `board_init_f_alloc_reserve`. A side effect of this is that the memory layout has changed as the following:
+----------------+ +----------------+ <----- SPL_STACK/ | ...... | | hart 0 stack | SYS_INIT_SP_ADDR | malloc_base | +----------------+ +----------------+ | hart 1 stack | | GD | +----------------+ If not SMP, N=1 +----------------+ | ...... | | hart 0 stack | +----------------+ +----------------+ ==> | hart N-1 stack| | hart 1 stack | +----------------+ +----------------+ | ...... | | ...... | | malloc_base | +----------------+ +----------------+ | hart N-1 stack| | GD | +----------------+ +----------------+ | | | |
Signed-off-by: Bo Gan ganboing@gmail.com Cc: Rick Chen rick@andestech.com Cc: Leo ycliang@andestech.com Cc: Sean Anderson seanga2@gmail.com Cc: Bin Meng bmeng.cn@gmail.com Cc: Lukas Auer lukas.auer@aisec.fraunhofer.de Reviewed-by: Rick Chen rick@andestech.com
v2:
- Fixed macro CONFIG_SYS_INIT_SP_ADDR -> SYS_INIT_SP_ADDR
- Tested SPL with VisionFive 2 board
arch/riscv/cpu/start.S | 37 ++++++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 13 deletions(-)
Reviewed-by: Leo Yu-Chi Liang ycliang@andestech.com