[PATCH v4 33/35] s390/unwind: Disable KMSAN checks
From: Ilya Leoshkevich <iii@linux.ibm.com>
Date: 2024-06-13 15:40:15
Also in:
linux-mm, linux-s390, lkml
Subsystem:
s390 architecture, the rest · Maintainers:
Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Linus Torvalds
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@google.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> --- 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