From 0cb1fd924126f1f581621a5e804df98a02be9dff Mon Sep 17 00:00:00 2001 From: Arun Easi Date: Thu, 3 Sep 2026 10:55:47 -0700 Subject: [PATCH] scsi: fnic: Fix missed link-up when critical IRQ targets offline CPU When CPU Hyper Threading is disabled, sibling CPUs remain present but are reported offline. Managed MSI-X IRQs can still receive affinity masks that include those offline CPUs. If a driver-critical vector is managed, it can be parked on an offline CPU and the driver may miss critical events such as link-up. Keep driver-critical vectors unmanaged so they can be migrated by the IRQ core when their target CPU is offlined. Since HWQ-0 is unmanaged now, in some queue combinations there can be no mappings to it in mq_map. So without the blk-mq fix mentioned below, system may crash during cpu offline/online tests. Fixes: 8a8449ca5e33 ("scsi: fnic: Modify ISRs to support multiqueue (MQ)") Cc: stable@vger.kernel.org Depends-on: commit 10845a105bbc ("blk-mq: skip CPU offline notify on unmapped hctx") Reviewed-by: Sesidhar Baddela Reviewed-by: Arulprabhu Ponnusamy Reviewed-by: Gian Carlo Boffa Reviewed-by: Karan Tilak Kumar Signed-off-by: Arun Easi Reviewed-by: Laurence Oberman Link: https://patch.msgid.link/20260903175547.57971-1-aeasi@cisco.com Signed-off-by: Martin K. Petersen (Oracle) --- drivers/scsi/fnic/fnic.h | 2 +- drivers/scsi/fnic/fnic_isr.c | 13 ++++++++--- drivers/scsi/fnic/fnic_main.c | 41 ++++++++++++++++++++++++++++++++++- 3 files changed, 51 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/fnic/fnic.h b/drivers/scsi/fnic/fnic.h index c576a7f5083e..3ba1592940ca 100644 --- a/drivers/scsi/fnic/fnic.h +++ b/drivers/scsi/fnic/fnic.h @@ -31,7 +31,7 @@ #define DRV_NAME "fnic" #define DRV_DESCRIPTION "Cisco FCoE HBA Driver" -#define DRV_VERSION "1.9.0.0" +#define DRV_VERSION "1.9.0.1" #define PFX DRV_NAME ": " #define DFX DRV_NAME "%d: " diff --git a/drivers/scsi/fnic/fnic_isr.c b/drivers/scsi/fnic/fnic_isr.c index 02856745580f..43149d8312ec 100644 --- a/drivers/scsi/fnic/fnic_isr.c +++ b/drivers/scsi/fnic/fnic_isr.c @@ -245,7 +245,14 @@ int fnic_set_intr_mode_msix(struct fnic *fnic) unsigned int m = ARRAY_SIZE(fnic->wq); unsigned int o = ARRAY_SIZE(fnic->hw_copy_wq); unsigned int min_irqs = n + m + 1 + 1; /*rq, raw wq, wq, err*/ - + /* + * Make driver critical vectors unmanaged, or else it can get tied + * to an offline CPU. This can happen when hyper-threading is off. + */ + struct irq_affinity affd = { + .pre_vectors = n + m + 1, /* rq, raw wq, 1 ioq */ + .post_vectors = 1, /* err */ + }; /* * We need n RQs, m WQs, o Copy WQs, n+m+o CQs, and n+m+o+1 INTRs * (last INTR is used for WQ/RQ errors and notification area) @@ -263,8 +270,8 @@ int fnic_set_intr_mode_msix(struct fnic *fnic) int vec_count = 0; int vecs = fnic->rq_count + fnic->raw_wq_count + fnic->wq_copy_count + 1; - vec_count = pci_alloc_irq_vectors(fnic->pdev, min_irqs, vecs, - PCI_IRQ_MSIX | PCI_IRQ_AFFINITY); + vec_count = pci_alloc_irq_vectors_affinity(fnic->pdev, min_irqs, + vecs, PCI_IRQ_MSIX|PCI_IRQ_AFFINITY, &affd); FNIC_ISR_DBG(KERN_INFO, fnic, "allocated %d MSI-X vectors\n", vec_count); diff --git a/drivers/scsi/fnic/fnic_main.c b/drivers/scsi/fnic/fnic_main.c index 9b3025007075..f13c381a66d7 100644 --- a/drivers/scsi/fnic/fnic_main.c +++ b/drivers/scsi/fnic/fnic_main.c @@ -744,8 +744,19 @@ static int fnic_nvme_drv_init(struct fnic *fnic) return ret; } +static void fnic_mq_init_queue_map(struct fnic *fnic, + struct blk_mq_queue_map *qmap) +{ + unsigned int cpu; + + for_each_possible_cpu(cpu) + qmap->mq_map[cpu] = 0; +} + void fnic_mq_map_queues_cpus(struct Scsi_Host *host) { + const struct cpumask *mask; + unsigned int queue, cpu; struct fnic *fnic = *((struct fnic **) shost_priv(host)); struct pci_dev *l_pdev = fnic->pdev; int intr_mode = fnic->config.intr_mode; @@ -766,7 +777,35 @@ void fnic_mq_map_queues_cpus(struct Scsi_Host *host) return; } - blk_mq_map_hw_queues(qmap, &l_pdev->dev, FNIC_PCI_OFFSET); + fnic_mq_init_queue_map(fnic, qmap); + + /* + * Setup CPU to Queue mapping for all managed MSI-X IRQs. + * Q0 is driver critical and non-managed, hence start from Q1. + */ + for (queue = 1; queue < qmap->nr_queues; queue++) { + int irq_num = pci_irq_vector(fnic->pdev, + queue + FNIC_PCI_OFFSET); + + if (irq_num < 0) + continue; + + mask = pci_irq_get_affinity(fnic->pdev, + queue + FNIC_PCI_OFFSET); + if (!mask) { + shost_printk(KERN_ERR, host, + "failed to get irq_affinity map for queue:%d\n", irq_num); + continue; + } + FNIC_MAIN_DBG(KERN_INFO, fnic, + "got irq_affinity map for %d:\n", irq_num); + for_each_cpu(cpu, mask) { + qmap->mq_map[cpu] = qmap->queue_offset + queue; + FNIC_MAIN_DBG(KERN_INFO, fnic, + "[Q%d] cpu:%d <=> irq:%d\n", + queue, cpu, irq_num); + } + } } static int fnic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)