The unwind code can read uninitialized frames. Furthermore, even in the good case, KMSAN does not emit shadow for backchains. Therefore disable it for the unwinding functions. Reviewed-by: Alexander Potapenko <glider@xxxxxxxxxx> Acked-by: Heiko Carstens <hca@xxxxxxxxxxxxx> Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx> --- arch/s390/kernel/unwind_bc.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/s390/kernel/unwind_bc.c b/arch/s390/kernel/unwind_bc.c index 0ece156fdd7c..cd44be2b6ce8 100644 --- a/arch/s390/kernel/unwind_bc.c +++ b/arch/s390/kernel/unwind_bc.c @@ -49,6 +49,8 @@ static inline bool is_final_pt_regs(struct unwind_state *state, READ_ONCE_NOCHECK(regs->psw.mask) & PSW_MASK_PSTATE; } +/* Avoid KMSAN false positives from touching uninitialized frames. */ +__no_kmsan_checks bool unwind_next_frame(struct unwind_state *state) { struct stack_info *info = &state->stack_info; @@ -118,6 +120,8 @@ bool unwind_next_frame(struct unwind_state *state) } EXPORT_SYMBOL_GPL(unwind_next_frame); +/* Avoid KMSAN false positives from touching uninitialized frames. */ +__no_kmsan_checks void __unwind_start(struct unwind_state *state, struct task_struct *task, struct pt_regs *regs, unsigned long first_frame) { -- 2.45.1