From: Palmer Dabbelt palmer@rivosinc.com
[ Upstream commit b003b3b77d65133a0011ae3b7b255347438c12f6 ]
The standard RISC-V ABIs all require 16-byte stack alignment. We're only calling that one function on the shadow stack so I doubt it'd result in a real issue, but might as well keep this lined up.
Fixes: 31da94c25aea ("riscv: add VMAP_STACK overflow detection") Reviewed-by: Jisheng Zhang jszhang@kernel.org Link: https://lore.kernel.org/r/20221130023515.20217-1-palmer@rivosinc.com Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/riscv/kernel/traps.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 2f4cd85fb651..4102c97309cc 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -211,7 +211,7 @@ static DEFINE_PER_CPU(unsigned long [OVERFLOW_STACK_SIZE/sizeof(long)], * shadow stack, handled_ kernel_ stack_ overflow(in kernel/entry.S) is used * to get per-cpu overflow stack(get_overflow_stack). */ -long shadow_stack[SHADOW_OVERFLOW_STACK_SIZE/sizeof(long)]; +long shadow_stack[SHADOW_OVERFLOW_STACK_SIZE/sizeof(long)] __aligned(16); asmlinkage unsigned long get_overflow_stack(void) { return (unsigned long)this_cpu_ptr(overflow_stack) +