diff options
| -rw-r--r-- | src/arch/riscv/trap_util.S | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/src/arch/riscv/trap_util.S b/src/arch/riscv/trap_util.S index 44cfab7c99..5582a0770c 100644 --- a/src/arch/riscv/trap_util.S +++ b/src/arch/riscv/trap_util.S @@ -128,10 +128,14 @@ trap_entry: .Lsmp_hang: bnez sp, .Lsmp_hang - # TODO: Use the old stack pointer (plus an offset) for exceptions in machine - # mode, to avoid overwriting stack data. - la sp, _estack - addi sp,sp,-MENTRY_FRAME_SIZE + # Use a different stack than in the main context, to to avoid overwriting + # stack data. + # TODO: Maybe use the old stack pointer (plus an offset) instead. But only if + # the previous mode was M, because it would be a very bad idea to use a stack + # pointer provided by unprivileged code! + la sp, _estack + addi sp, sp, -2048 # 2 KiB is half of the stack space + addi sp, sp, -MENTRY_FRAME_SIZE save_tf move a0,sp |