diff options
| -rw-r--r-- | arch/riscv/kernel/traps.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index acdfcacd7e57..336d4aadadb1 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -200,18 +200,18 @@ void __init trap_init(void) } #ifdef CONFIG_VMAP_STACK +/* + * Extra stack space that allows us to provide panic messages when the kernel + * has overflowed its stack. + */ static DEFINE_PER_CPU(unsigned long [OVERFLOW_STACK_SIZE/sizeof(long)], overflow_stack)__aligned(16); /* - * shadow stack, handled_ kernel_ stack_ overflow(in kernel/entry.S) is used - * to get per-cpu overflow stack(get_overflow_stack). + * A temporary stack for use by handle_kernel_stack_overflow. This is used so + * we can call into C code to get the per-hart overflow stack. Usage of this + * stack must be protected by spin_shadow_stack. */ 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) + - OVERFLOW_STACK_SIZE; -} /* * A pseudo spinlock to protect the shadow stack from being used by multiple @@ -222,6 +222,12 @@ asmlinkage unsigned long get_overflow_stack(void) */ unsigned long spin_shadow_stack; +asmlinkage unsigned long get_overflow_stack(void) +{ + return (unsigned long)this_cpu_ptr(overflow_stack) + + OVERFLOW_STACK_SIZE; +} + asmlinkage void handle_bad_stack(struct pt_regs *regs) { unsigned long tsk_stk = (unsigned long)current->stack; |