From 1833c9f647e9bda1cd24653ff8f9c207b5f5b911 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Sat, 21 Mar 2015 12:43:08 +0100 Subject: [PATCH] s390/smp: reenable smt after resume After a suspend/resume cycle we missed to enable smt again, which leads to all sorts of bugs, since the kernel assumes smt is enabled, while the hardware thinks it is not. Reported-and-tested-by: Sebastian Ott Reported-by: Stefan Haberland Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/swsusp_asm64.S | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/s390/kernel/swsusp_asm64.S b/arch/s390/kernel/swsusp_asm64.S index 6b09fdffbd2f..ca6294645dd3 100644 --- a/arch/s390/kernel/swsusp_asm64.S +++ b/arch/s390/kernel/swsusp_asm64.S @@ -177,6 +177,17 @@ restart_entry: lhi %r1,1 sigp %r1,%r0,SIGP_SET_ARCHITECTURE sam64 +#ifdef CONFIG_SMP + larl %r1,smp_cpu_mt_shift + icm %r1,15,0(%r1) + jz smt_done + llgfr %r1,%r1 +smt_loop: + sigp %r1,%r0,SIGP_SET_MULTI_THREADING + brc 8,smt_done /* accepted */ + brc 2,smt_loop /* busy, try again */ +smt_done: +#endif larl %r1,.Lnew_pgm_check_psw lpswe 0(%r1) pgm_check_entry: -- 2.20.1