Commit 8f100bb1 authored Mar 10, 2016 by Heiko Carstens Committed by Martin Schwidefsky Mar 10, 2016

s390/cpumf: add missing lpp magic initialization



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@cn.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes: e22cf8ca ("s390/cpumf: rework program parameter setting to detect guest samples")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

parent 7eb792bf

arch/s390/kernel/setup.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -327,6 +327,7 @@ 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,

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