4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Heiko Carstens <heiko.carstens@xxxxxxxxxx> commit 8f100bb1ff27873dd71f636da670e503b9ade3c6 upstream. Add the missing lpp magic initialization for cpu 0. Without this all samples on cpu 0 do not have the most significant bit set in the program parameter field, which we use to distinguish between guest and host samples if the pid is also 0. We did initialize the lpp magic in the absolute zero lowcore but forgot that when switching to the allocated lowcore on cpu 0 only. Reported-by: Shu Juan Zhang <zhshuj@xxxxxxxxxx> Acked-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> Fixes: e22cf8ca6f75 ("s390/cpumf: rework program parameter setting to detect guest samples") Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/s390/kernel/setup.c | 1 + 1 file changed, 1 insertion(+) --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -329,6 +329,7 @@ static void __init setup_lowcore(void) + PAGE_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs); lc->current_task = (unsigned long) init_thread_union.thread_info.task; lc->thread_info = (unsigned long) &init_thread_union; + lc->lpp = LPP_MAGIC; lc->machine_flags = S390_lowcore.machine_flags; lc->stfl_fac_list = S390_lowcore.stfl_fac_list; memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list, -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html