@@ -487,8 +487,8 @@ void asm_offsets(void)
OFFSET(SBI_HART_BOOT_STACK_PTR_OFFSET, sbi_hart_boot_data, stack_ptr);
DEFINE(STACKFRAME_SIZE_ON_STACK, ALIGN(sizeof(struct stackframe), STACK_ALIGN));
- OFFSET(STACKFRAME_FP, stackframe, fp);
- OFFSET(STACKFRAME_RA, stackframe, ra);
+ DEFINE(STACKFRAME_FP, offsetof(struct stackframe, fp) - sizeof(struct stackframe));
+ DEFINE(STACKFRAME_RA, offsetof(struct stackframe, ra) - sizeof(struct stackframe));
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS
DEFINE(FREGS_SIZE_ON_STACK, ALIGN(sizeof(struct ftrace_regs), STACK_ALIGN));
@@ -246,8 +246,8 @@ SYM_CODE_END(ret_from_fork)
SYM_FUNC_START(call_on_irq_stack)
/* Create a frame record to save ra and s0 (fp) */
addi sp, sp, -STACKFRAME_SIZE_ON_STACK
- REG_S ra, STACKFRAME_RA(sp)
- REG_S s0, STACKFRAME_FP(sp)
+ REG_S ra, (STACKFRAME_SIZE_ON_STACK + STACKFRAME_RA)(sp)
+ REG_S s0, (STACKFRAME_SIZE_ON_STACK + STACKFRAME_FP)(sp)
addi s0, sp, STACKFRAME_SIZE_ON_STACK
/* Switch to the per-CPU shadow call stack */
@@ -265,8 +265,8 @@ SYM_FUNC_START(call_on_irq_stack)
/* Switch back to the thread stack and restore ra and s0 */
addi sp, s0, -STACKFRAME_SIZE_ON_STACK
- REG_L ra, STACKFRAME_RA(sp)
- REG_L s0, STACKFRAME_FP(sp)
+ REG_L ra, (STACKFRAME_SIZE_ON_STACK + STACKFRAME_RA)(sp)
+ REG_L s0, (STACKFRAME_SIZE_ON_STACK + STACKFRAME_FP)(sp)
addi sp, sp, STACKFRAME_SIZE_ON_STACK
ret
call_on_irq_stack() uses struct member offsets to set up its link in the frame record list. On riscv32, `struct stackframe` is the wrong size to maintain stack pointer alignment, so STACKFRAME_SIZE_ON_STACK includes padding. However, the ABI requires the frame record to be placed immediately below the address stored in s0, so the padding must come before the struct members. Fix the layout by making STACKFRAME_FP and STACKFRAME_RA the negative offsets from s0, instead of the positive offsets from sp. Fixes: 82982fdd5133 ("riscv: Deduplicate IRQ stack switching") Signed-off-by: Samuel Holland <samuel.holland@sifive.com> --- arch/riscv/kernel/asm-offsets.c | 4 ++-- arch/riscv/kernel/entry.S | 8 ++++---- 2 files changed, 6 insertions(+), 6 deletions(-)