From: Alexander Gordeev <agordeev@linux.ibm.com>
Date: Wed, 30 Mar 2022 17:50:16 +0000 (+0200)
Subject: s390/smp: sort out physical vs virtual CPU0 lowcore pointer
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=7714e16f791d948c8bb58aa23bf8ef60b9bba646;p=linux.git

s390/smp: sort out physical vs virtual CPU0 lowcore pointer

SPX instruction called from set_prefix() expects physical
address of the lowcore to be installed, but instead the
virtual address is passed.

Note: this does not fix a bug currently, since virtual and
physical addresses are identical.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
---

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index d860ac3009197..8d91eccc09632 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -494,7 +494,7 @@ static void __init setup_lowcore_dat_off(void)
 	lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
 	lc->preempt_count = PREEMPT_DISABLED;
 
-	set_prefix((u32)(unsigned long) lc);
+	set_prefix(__pa(lc));
 	lowcore_ptr[0] = lc;
 }