scsi: lpfc: Fix stack trace seen while setting rrq active

Call traces have been observed running different tests that involve aborts
and setting the rrq active flag.  The lpfc_set_rrq_active routine is doing
a mempool_alloc under the soft_irq processing level. When the mempool needs
to get a new buffer from the free pool and has to wait for memory to become
free it will check the flags passed in on the alloc and dump the stack if
the thread is running in interrupt context.

Replace the GFP_KERNEL flag with GFP_ATOMIC so that the memory allocation
will not attempt to sleep if there is no mem available.

Link: https://lore.kernel.org/r/20200630215001.70793-7-jsmart2021@gmail.com
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/lpfc/lpfc_mem.c b/drivers/scsi/lpfc/lpfc_mem.c
index 726f661..e8c0066 100644 (file)
--- a/drivers/scsi/lpfc/lpfc_mem.c
+++ b/drivers/scsi/lpfc/lpfc_mem.c
@@ -45,6 +45,7 @@
 #define LPFC_MBUF_POOL_SIZE     64      /* max elements in MBUF safety pool */
 #define LPFC_MEM_POOL_SIZE      64      /* max elem in non-DMA safety pool */
 #define LPFC_DEVICE_DATA_POOL_SIZE 64   /* max elements in device data pool */
+#define LPFC_RRQ_POOL_SIZE     256     /* max elements in non-DMA  pool */
 
 int
 lpfc_mem_alloc_active_rrq_pool_s4(struct lpfc_hba *phba) {
@@ -121,7 +122,7 @@ lpfc_mem_alloc(struct lpfc_hba *phba, int align)
 
        if (phba->sli_rev == LPFC_SLI_REV4) {
                phba->rrq_pool =
-                       mempool_create_kmalloc_pool(LPFC_MEM_POOL_SIZE,
+                       mempool_create_kmalloc_pool(LPFC_RRQ_POOL_SIZE,
                                                sizeof(struct lpfc_node_rrq));
                if (!phba->rrq_pool)
                        goto fail_free_nlp_mem_pool;

diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index cefc3cb..88e78ff 100644 (file)
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -1079,7 +1079,7 @@ lpfc_set_rrq_active(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp,
                goto out;
 
        spin_unlock_irqrestore(&phba->hbalock, iflags);
-       rrq = mempool_alloc(phba->rrq_pool, GFP_KERNEL);
+       rrq = mempool_alloc(phba->rrq_pool, GFP_ATOMIC);
        if (!rrq) {
                lpfc_printf_log(phba, KERN_INFO, LOG_SLI,
                                "3155 Unable to allocate RRQ xri:0x%x rxid:0x%x"