From: Alexander Gordeev Date: Mon, 3 Apr 2023 06:44:36 +0000 (+0200) Subject: s390/kexec: turn DAT mode off immediately before purgatory X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=7a04d491edf4766e7724671355b1ab27cae81a4a;p=linux.git s390/kexec: turn DAT mode off immediately before purgatory The kernel code is not guaranteed DAT-off mode safe. Turn the DAT mode off immediately before entering the purgatory. Further, to avoid subtle side effects reset the system immediately before turning DAT mode off while making all necessary preparations in advance. Signed-off-by: Alexander Gordeev Reviewed-by: Heiko Carstens Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik --- diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c index 2a8e73266428e..eb473fc835b23 100644 --- a/arch/s390/kernel/machine_kexec.c +++ b/arch/s390/kernel/machine_kexec.c @@ -254,14 +254,13 @@ static void __do_machine_kexec(void *data) relocate_kernel_t data_mover; struct kimage *image = data; - s390_reset_system(); data_mover = (relocate_kernel_t) page_to_phys(image->control_code_page); - - __arch_local_irq_stnsm(0xfb); /* disable DAT - avoid no-execute */ - /* Call the moving routine */ diag308_subcode = DIAG308_CLEAR_RESET; if (sclp.has_iplcc) diag308_subcode |= DIAG308_FLAG_EI; + s390_reset_system(); + + __arch_local_irq_stnsm(0xfb); /* disable DAT - avoid no-execute */ (*data_mover)(&image->head, image->start, diag308_subcode); /* Die if kexec returns */