When cpumask_next() the return value is greater than or equal to
nr_cpu_ids, it indicates invalid.

Before commit 596ff4a09b89 ("cpumask: re-introduce constant-sized cpumask
optimizations"), when cpumask_next() returned an invalid cpu, the driver
used the judgment equal to nr_cpu_ids to indicate the invalid cpu, so it
happened to work normally, but this is the wrong approach.

After commit 596ff4a09b89 ("cpumask: re-introduce constant-sized cpumask
optimizations"), these incorrect practices actively buggy, so fix it to
correctly.

Signed-off-by: Vernon Yang <vernon...@gmail.com>
---
 drivers/scsi/lpfc/lpfc_init.c | 43 ++++++++++++++++-------------------
 1 file changed, 20 insertions(+), 23 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index 61958a24a43d..acfffdbe9ba1 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -12473,6 +12473,16 @@ lpfc_hba_eq_hdl_array_init(struct lpfc_hba *phba)
        }
 }
 
+static inline int lpfc_next_present_cpu(int n, int first_cpu)
+{
+       n = cpumask_next(n, cpu_present_mask);
+
+       if (n >= nr_cpu_ids)
+               n = first_cpu;
+
+       return n;
+}
+
 /**
  * lpfc_cpu_affinity_check - Check vector CPU affinity mappings
  * @phba: pointer to lpfc hba data structure.
@@ -12561,10 +12571,8 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int 
vectors)
                                    (new_cpup->eq != LPFC_VECTOR_MAP_EMPTY) &&
                                    (new_cpup->phys_id == cpup->phys_id))
                                        goto found_same;
-                               new_cpu = cpumask_next(
-                                       new_cpu, cpu_present_mask);
-                               if (new_cpu == nr_cpumask_bits)
-                                       new_cpu = first_cpu;
+
+                               new_cpu = lpfc_next_present_cpu(new_cpu, 
first_cpu);
                        }
                        /* At this point, we leave the CPU as unassigned */
                        continue;
@@ -12576,9 +12584,7 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int 
vectors)
                         * chance of having multiple unassigned CPU entries
                         * selecting the same IRQ.
                         */
-                       start_cpu = cpumask_next(new_cpu, cpu_present_mask);
-                       if (start_cpu == nr_cpumask_bits)
-                               start_cpu = first_cpu;
+                       start_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
 
                        lpfc_printf_log(phba, KERN_INFO, LOG_INIT,
                                        "3337 Set Affinity: CPU %d "
@@ -12611,10 +12617,8 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int 
vectors)
                                if (!(new_cpup->flag & LPFC_CPU_MAP_UNASSIGN) &&
                                    (new_cpup->eq != LPFC_VECTOR_MAP_EMPTY))
                                        goto found_any;
-                               new_cpu = cpumask_next(
-                                       new_cpu, cpu_present_mask);
-                               if (new_cpu == nr_cpumask_bits)
-                                       new_cpu = first_cpu;
+
+                               new_cpu = lpfc_next_present_cpu(new_cpu, 
first_cpu);
                        }
                        /* We should never leave an entry unassigned */
                        lpfc_printf_log(phba, KERN_ERR, LOG_INIT,
@@ -12630,9 +12634,7 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int 
vectors)
                         * chance of having multiple unassigned CPU entries
                         * selecting the same IRQ.
                         */
-                       start_cpu = cpumask_next(new_cpu, cpu_present_mask);
-                       if (start_cpu == nr_cpumask_bits)
-                               start_cpu = first_cpu;
+                       start_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
 
                        lpfc_printf_log(phba, KERN_INFO, LOG_INIT,
                                        "3338 Set Affinity: CPU %d "
@@ -12703,9 +12705,8 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int 
vectors)
                            new_cpup->core_id == cpup->core_id) {
                                goto found_hdwq;
                        }
-                       new_cpu = cpumask_next(new_cpu, cpu_present_mask);
-                       if (new_cpu == nr_cpumask_bits)
-                               new_cpu = first_cpu;
+
+                       new_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
                }
 
                /* If we can't match both phys_id and core_id,
@@ -12718,9 +12719,7 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int 
vectors)
                            new_cpup->phys_id == cpup->phys_id)
                                goto found_hdwq;
 
-                       new_cpu = cpumask_next(new_cpu, cpu_present_mask);
-                       if (new_cpu == nr_cpumask_bits)
-                               new_cpu = first_cpu;
+                       new_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
                }
 
                /* Otherwise just round robin on cfg_hdw_queue */
@@ -12729,9 +12728,7 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int 
vectors)
                goto logit;
  found_hdwq:
                /* We found an available entry, copy the IRQ info */
-               start_cpu = cpumask_next(new_cpu, cpu_present_mask);
-               if (start_cpu == nr_cpumask_bits)
-                       start_cpu = first_cpu;
+               start_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
                cpup->hdwq = new_cpup->hdwq;
  logit:
                lpfc_printf_log(phba, KERN_INFO, LOG_INIT,
-- 
2.34.1

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