* Martin Schwidefsky (schwidefsky@de.ibm.com)
*/
-#include <linux/config.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/workqueue.h>
+#include <linux/time.h>
+#include <linux/kthread.h>
#include <asm/lowcore.h>
unsigned int chain;
sem = (struct semaphore *)param;
- /* Set a nice name. */
- daemonize("kmcheck");
repeat:
down_interruptible(sem);
slow = 0;
break;
case CRW_RSC_CPATH:
pr_debug("source is channel path %02X\n", crw[0].rsid);
+ /*
+ * Check for solicited machine checks. These are
+ * created by reset channel path and need not be
+ * reported to the common I/O layer.
+ */
+ if (crw[chain].slct) {
+ DBG(KERN_INFO"solicited machine check for "
+ "channel path %02X\n", crw[0].rsid);
+ break;
+ }
switch (crw[0].erc) {
case CRW_ERC_IPARM: /* Path has come. */
ret = chp_process_crw(crw[0].rsid, 1);
return kill_task;
}
+#define MAX_IPD_COUNT 29
+#define MAX_IPD_TIME (5 * 60 * USEC_PER_SEC) /* 5 minutes */
+
/*
* machine check handler.
*/
void
s390_do_machine_check(struct pt_regs *regs)
{
+ static DEFINE_SPINLOCK(ipd_lock);
+ static unsigned long long last_ipd;
+ static int ipd_count;
+ unsigned long long tmp;
struct mci *mci;
struct mcck_struct *mcck;
int umode;
+ lockdep_off();
+
mci = (struct mci *) &S390_lowcore.mcck_interruption_code;
mcck = &__get_cpu_var(cpu_mcck);
umode = user_mode(regs);
s390_handle_damage("processing backup machine "
"check with damage.");
}
- if (!umode)
- s390_handle_damage("processing backup machine "
- "check in kernel mode.");
- mcck->kill_task = 1;
- mcck->mcck_code = *(unsigned long long *) mci;
+
+ /*
+ * Nullifying exigent condition, therefore we might
+ * retry this instruction.
+ */
+
+ spin_lock(&ipd_lock);
+
+ tmp = get_clock();
+
+ if (((tmp - last_ipd) >> 12) < MAX_IPD_TIME)
+ ipd_count++;
+ else
+ ipd_count = 1;
+
+ last_ipd = tmp;
+
+ if (ipd_count == MAX_IPD_COUNT)
+ s390_handle_damage("too many ipd retries.");
+
+ spin_unlock(&ipd_lock);
}
else {
/* Processing damage -> stopping machine */
mcck->warning = 1;
set_thread_flag(TIF_MCCK_PENDING);
}
+ lockdep_on();
}
/*
static int __init
machine_check_crw_init (void)
{
- kernel_thread(s390_collect_crw_info, &m_sem, CLONE_FS|CLONE_FILES);
+ kthread_run(s390_collect_crw_info, &m_sem, "kmcheck");
ctl_set_bit(14, 28); /* enable channel report MCH */
return 0;
}