diff options
| author | Jisheng Zhang <[email protected]> | 2024-07-21 01:06:59 +0800 |
|---|---|---|
| committer | Palmer Dabbelt <[email protected]> | 2024-09-15 20:58:25 -0700 |
| commit | 8f1534e7440382d118c3d655d3a6014128b2086d (patch) | |
| tree | 125343c989be1ae407db466d0e9ca5edd5f4eff9 | |
| parent | 7e340f4fad46b766705be96f5d1c764a397a7a36 (diff) | |
riscv: avoid Imbalance in RAS
Inspired by[1], modify the code to remove the code of modifying ra to
avoid imbalance RAS (return address stack) which may lead to incorret
predictions on return.
Link: https://lore.kernel.org/linux-riscv/[email protected]/ [1]
Signed-off-by: Jisheng Zhang <[email protected]>
Reviewed-by: Cyril Bur <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>
| -rw-r--r-- | arch/riscv/kernel/entry.S | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index fc41472d512e..c200d329d4bd 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -326,8 +326,8 @@ SYM_CODE_START(ret_from_fork) jalr s0 1: move a0, sp /* pt_regs */ - la ra, ret_from_exception - tail syscall_exit_to_user_mode + call syscall_exit_to_user_mode + j ret_from_exception SYM_CODE_END(ret_from_fork) #ifdef CONFIG_IRQ_STACKS |