From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> commit eb9be8310c58c166f9fae3b71c0ad9d6741b4897 upstream. The patchwork automation reported a sparse complaint that spin_shadow_stack was not declared and should be static: ../arch/riscv/kernel/traps.c:335:15: warning: symbol 'spin_shadow_stack' was not declared. Should it be static? However, this is used in entry.S and therefore shouldn't be static. The same applies to the shadow_stack that this pseudo spinlock is trying to protect, so do like its charge and add a declaration to thread_info.h Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> Fixes: 7e1864332fbc ("riscv: fix race when vmap stack overflow") Reviewed-by: Guo Ren <guoren@xxxxxxxxxx> Link: https://lore.kernel.org/r/20230210185945.915806-1-conor@xxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/riscv/include/asm/thread_info.h | 1 + 1 file changed, 1 insertion(+) --- a/arch/riscv/include/asm/thread_info.h +++ b/arch/riscv/include/asm/thread_info.h @@ -43,6 +43,7 @@ #ifndef __ASSEMBLY__ extern long shadow_stack[SHADOW_OVERFLOW_STACK_SIZE / sizeof(long)]; +extern unsigned long spin_shadow_stack; #include <asm/processor.h> #include <asm/csr.h>