The following commit has been merged in the linux branch: commit f8501ba77d69c88a65e4ebbe03bdc65b1edb0b86 Author: Heiko Carstens heiko.carstens@de.ibm.com Date: Thu Oct 29 15:04:13 2009 +0100

[S390] smp: fix sigp stop handling

According to the architecture a cpu must not necessarily enter stopped state after completion of a sigp instruction with "stop" order code. So remove the BUG() statement after self sending sigp stop to avoid that it ever gets reached. Also add a sigp busy check to make sure that the order gets delivered.

Signed-off-by: Heiko Carstens heiko.carstens@de.ibm.com Signed-off-by: Martin Schwidefsky schwidefsky@de.ibm.com

diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c index ee57a42..4890ac6 100644 --- a/arch/s390/kernel/ipl.c +++ b/arch/s390/kernel/ipl.c @@ -1595,10 +1595,9 @@ static void stop_run(struct shutdown_trigger *trigger) { if (strcmp(trigger->name, ON_PANIC_STR) == 0) disabled_wait((unsigned long) __builtin_return_address(0)); - else { - signal_processor(smp_processor_id(), sigp_stop); - for (;;); - } + while (signal_processor(smp_processor_id(), sigp_stop) == sigp_busy) + cpu_relax(); + for (;;); }

static struct shutdown_action stop_action = {SHUTDOWN_ACTION_STOP_STR, diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index c699ac5..c99c45b 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -647,8 +647,8 @@ void __cpu_die(unsigned int cpu) void cpu_die(void) { idle_task_exit(); - signal_processor(smp_processor_id(), sigp_stop); - BUG(); + while (signal_processor(smp_processor_id(), sigp_stop) == sigp_busy) + cpu_relax(); for (;;); }

diff --git a/arch/s390/kernel/swsusp_asm64.S b/arch/s390/kernel/swsusp_asm64.S index 7c8653e..0f4ef3b 100644 --- a/arch/s390/kernel/swsusp_asm64.S +++ b/arch/s390/kernel/swsusp_asm64.S @@ -199,6 +199,7 @@ pgm_check_entry: brc 2,4b /* busy, try again */ 5: sigp %r9,%r2,__SIGP_STOP /* stop resume (current) CPU */ + brc 2,5b /* busy, try again */ 6: j 6b

restart_suspend: