Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-24 05:02:12 +00:00
Code Issues Packages Projects Releases Wiki Activity

[S390] Dont overwrite lowcores on smp_send_stop().

Browse Source 
Don't perform a sigp store-status-at-address on smp_send_stop().
It will overwrite the lowcores of other cpus and destroys valueable
debug informations.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Heiko Carstens 2007-11-20 11:13:37 +01:00 committed by Martin Schwidefsky
parent ce7e9fae8d
commit 677d762319
1 changed files with 7 additions and 49 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

56
arch/s390/kernel/smp.c
View File

@ -193,10 +193,16 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
}
EXPORT_SYMBOL(smp_call_function_single);
static void do_send_stop(void)
void smp_send_stop(void)
{
int cpu, rc;
/* Disable all interrupts/machine checks */
__load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK);
/* write magic number to zero page (absolute 0) */
lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC;
/* stop all processors */
for_each_online_cpu(cpu) {
if (cpu == smp_processor_id())
@ -204,60 +210,12 @@ static void do_send_stop(void)
do {
rc = signal_processor(cpu, sigp_stop);
} while (rc == sigp_busy);
}
}
static void do_store_status(void)
{
int cpu, rc;
/* store status of all processors in their lowcores (real 0) */
for_each_online_cpu(cpu) {
if (cpu == smp_processor_id())
continue;
do {
rc = signal_processor_p(
(__u32)(unsigned long) lowcore_ptr[cpu], cpu,
sigp_store_status_at_address);
} while (rc == sigp_busy);
}
}
static void do_wait_for_stop(void)
{
int cpu;
/* Wait for all other cpus to enter stopped state */
for_each_online_cpu(cpu) {
if (cpu == smp_processor_id())
continue;
while (!smp_cpu_not_running(cpu))
cpu_relax();
}
}
/*
* this function sends a 'stop' sigp to all other CPUs in the system.
* it goes straight through.
*/
void smp_send_stop(void)
{
/* Disable all interrupts/machine checks */
__load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK);
/* write magic number to zero page (absolute 0) */
lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC;
/* stop other processors. */
do_send_stop();
/* wait until other processors are stopped */
do_wait_for_stop();
/* store status of other processors. */
do_store_status();
}
/*
* Reboot, halt and power_off routines for SMP.
*/