From 1623a554c68f352c17d0a358bc62580dc187f06b Mon Sep 17 00:00:00 2001 From: Vasily Gorbik Date: Mon, 23 Feb 2026 23:33:52 +0100 Subject: [PATCH] s390/kexec: Disable stack protector in s390_reset_system() s390_reset_system() calls set_prefix(0), which switches back to the absolute lowcore. At that point the stack protector canary no longer matches the canary from the lowcore the function was entered with, so the stack check fails. Mark s390_reset_system() __no_stack_protector. This is safe here since its callers (__do_machine_kdump() and __do_machine_kexec()) are effectively no-return and fall back to disabled_wait() on failure. Fixes: f5730d44e05e ("s390: Add stackprotector support") Reported-by: Nikita Dubrovskii Reviewed-by: Heiko Carstens Acked-by: Alexander Gordeev Signed-off-by: Vasily Gorbik --- arch/s390/kernel/ipl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c index dcdc7e274848..049c557c452f 100644 --- a/arch/s390/kernel/ipl.c +++ b/arch/s390/kernel/ipl.c @@ -2377,7 +2377,7 @@ void __init setup_ipl(void) atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb); } -void s390_reset_system(void) +void __no_stack_protector s390_reset_system(void) { /* Disable prefixing */ set_prefix(0);