s390 fixes for 6.17-rc6

- ptep_modify_prot_start() may be called in a loop, which might lead
   to the preempt_count overflow due to the unnecessary preemption
   disabling. Do not disable preemption to prevent the overflow
 
 - Events of type PERF_TYPE_HARDWARE are not tested for sampling and
   return -EOPNOTSUPP eventually. Instead, deny all sampling events by
   CPUMF counter facility and return -ENOENT to allow other PMUs to be
   tried
 
 - The PAI PMU driver returns -EINVAL if an event out of its range.
   That aborts a search for an alternative PMU driver. Instead, return
   -ENOENT to allow other PMUs to be tried
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Merge tag 's390-6.17-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fixes from Alexander Gordeev:

 - ptep_modify_prot_start() may be called in a loop, which might lead to
   the preempt_count overflow due to the unnecessary preemption
   disabling. Do not disable preemption to prevent the overflow

 - Events of type PERF_TYPE_HARDWARE are not tested for sampling and
   return -EOPNOTSUPP eventually.

   Instead, deny all sampling events by CPUMF counter facility and
   return -ENOENT to allow other PMUs to be tried

 - The PAI PMU driver returns -EINVAL if an event out of its range. That
   aborts a search for an alternative PMU driver.

   Instead, return -ENOENT to allow other PMUs to be tried

* tag 's390-6.17-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/cpum_cf: Deny all sampling events by counter PMU
  s390/pai: Deny all events not handled by this PMU
  s390/mm: Prevent possible preempt_count overflow

arch/s390/kernel/perf_cpum_cf.c

@@ -760,8 +760,6 @@ static int __hw_perf_event_init(struct perf_event *event, unsigned int type)
 		break;
 
 	case PERF_TYPE_HARDWARE:
-		if (is_sampling_event(event))	/* No sampling support */
-			return -ENOENT;
 		ev = attr->config;
 		if (!attr->exclude_user && attr->exclude_kernel) {
 			/*
@@ -859,6 +857,8 @@ static int cpumf_pmu_event_init(struct perf_event *event)
 	unsigned int type = event->attr.type;
 	int err = -ENOENT;
 
+	if (is_sampling_event(event))	/* No sampling support */
+		return err;
 	if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_RAW)
 		err = __hw_perf_event_init(event, type);
 	else if (event->pmu->type == type)

arch/s390/kernel/perf_pai_crypto.c

@@ -285,10 +285,10 @@ static int paicrypt_event_init(struct perf_event *event)
 	/* PAI crypto PMU registered as PERF_TYPE_RAW, check event type */
 	if (a->type != PERF_TYPE_RAW && event->pmu->type != a->type)
 		return -ENOENT;
-	/* PAI crypto event must be in valid range */
+	/* PAI crypto event must be in valid range, try others if not */
 	if (a->config < PAI_CRYPTO_BASE ||
 	    a->config > PAI_CRYPTO_BASE + paicrypt_cnt)
-		return -EINVAL;
+		return -ENOENT;
 	/* Allow only CRYPTO_ALL for sampling */
 	if (a->sample_period && a->config != PAI_CRYPTO_BASE)
 		return -EINVAL;

arch/s390/kernel/perf_pai_ext.c

@@ -265,7 +265,7 @@ static int paiext_event_valid(struct perf_event *event)
 		event->hw.config_base = offsetof(struct paiext_cb, acc);
 		return 0;
 	}
-	return -EINVAL;
+	return -ENOENT;
 }
 
 /* Might be called on different CPU than the one the event is intended for. */

arch/s390/mm/pgtable.c

@@ -335,7 +335,6 @@ pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr,
 	int nodat;
 	struct mm_struct *mm = vma->vm_mm;
 
-	preempt_disable();
 	pgste = ptep_xchg_start(mm, addr, ptep);
 	nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
 	old = ptep_flush_lazy(mm, addr, ptep, nodat);
@@ -360,7 +359,6 @@ void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
 	} else {
 		set_pte(ptep, pte);
 	}
-	preempt_enable();
 }
 
 static inline void pmdp_idte_local(struct mm_struct *mm,