From b44f320fffc93a52f0c54320969589e2b8eff698 Mon Sep 17 00:00:00 2001 From: Sriharsha Allenki Date: Wed, 19 May 2021 13:41:49 +0530 Subject: [PATCH] pci: msm: Fix spinlock lockup during notify_client Currently interrupts are not being disabled locally when an event callback is being used. This can lead to a scenario where we try to acquire the same lock as part of global irq handler when a client callback was in progress. Fix this by disabling the interruts locally by using a irqsave version of spinlock when an event callback is being used. Change-Id: I8a2eff826e24fb32c60bd5769390faa960669eb7 Signed-off-by: Sriharsha Allenki --- drivers/pci/controller/pci-msm.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/drivers/pci/controller/pci-msm.c b/drivers/pci/controller/pci-msm.c index 06b5648111a3..2e287aa66279 100644 --- a/drivers/pci/controller/pci-msm.c +++ b/drivers/pci/controller/pci-msm.c @@ -4996,8 +4996,9 @@ static void msm_pcie_notify_client(struct msm_pcie_dev_t *dev, struct msm_pcie_register_event *reg_itr; struct msm_pcie_notify *notify; struct msm_pcie_notify client_notify; + unsigned long flags; - spin_lock(&dev->evt_reg_list_lock); + spin_lock_irqsave(&dev->evt_reg_list_lock, flags); list_for_each_entry(reg_itr, &dev->event_reg_list, node) { if ((reg_itr->events & event) && reg_itr->callback) { notify = ®_itr->notify; @@ -5020,7 +5021,7 @@ static void msm_pcie_notify_client(struct msm_pcie_dev_t *dev, break; } } - spin_unlock(&dev->evt_reg_list_lock); + spin_unlock_irqrestore(&dev->evt_reg_list_lock, flags); } static void handle_wake_func(struct work_struct *work) @@ -8026,6 +8027,7 @@ int msm_pcie_register_event(struct msm_pcie_register_event *reg) struct msm_pcie_dev_t *pcie_dev; struct msm_pcie_register_event *reg_itr; struct pci_dev *pcidev; + unsigned long flags; if (!reg) { pr_err("PCIe: Event registration is NULL\n"); @@ -8046,19 +8048,19 @@ int msm_pcie_register_event(struct msm_pcie_register_event *reg) pcidev = (struct pci_dev *)reg->user; - spin_lock(&pcie_dev->evt_reg_list_lock); + spin_lock_irqsave(&pcie_dev->evt_reg_list_lock, flags); list_for_each_entry(reg_itr, &pcie_dev->event_reg_list, node) { if (reg_itr->user == reg->user) { PCIE_ERR(pcie_dev, "PCIe: RC%d: EP BDF 0x%4x already registered\n", pcie_dev->rc_idx, PCI_DEVID(pcidev->bus->number, pcidev->devfn)); - spin_unlock(&pcie_dev->evt_reg_list_lock); + spin_unlock_irqrestore(&pcie_dev->evt_reg_list_lock, flags); return -EEXIST; } } list_add_tail(®->node, &pcie_dev->event_reg_list); - spin_unlock(&pcie_dev->evt_reg_list_lock); + spin_unlock_irqrestore(&pcie_dev->evt_reg_list_lock, flags); if (pcie_dev->drv_supported) schedule_work(&pcie_drv.drv_connect); @@ -8072,6 +8074,7 @@ int msm_pcie_deregister_event(struct msm_pcie_register_event *reg) struct msm_pcie_dev_t *pcie_dev; struct pci_dev *pcidev; struct msm_pcie_register_event *reg_itr; + unsigned long flags; if (!reg) { pr_err("PCIe: Event deregistration is NULL\n"); @@ -8093,11 +8096,11 @@ int msm_pcie_deregister_event(struct msm_pcie_register_event *reg) pcidev = (struct pci_dev *)reg->user; - spin_lock(&pcie_dev->evt_reg_list_lock); + spin_lock_irqsave(&pcie_dev->evt_reg_list_lock, flags); list_for_each_entry(reg_itr, &pcie_dev->event_reg_list, node) { if (reg_itr->user == reg->user) { list_del(®->node); - spin_unlock(&pcie_dev->evt_reg_list_lock); + spin_unlock_irqrestore(&pcie_dev->evt_reg_list_lock, flags); PCIE_DBG(pcie_dev, "PCIe: RC%d: Event deregistered for BDF 0x%04x\n", pcie_dev->rc_idx, @@ -8105,7 +8108,7 @@ int msm_pcie_deregister_event(struct msm_pcie_register_event *reg) return 0; } } - spin_unlock(&pcie_dev->evt_reg_list_lock); + spin_unlock_irqrestore(&pcie_dev->evt_reg_list_lock, flags); PCIE_DBG(pcie_dev, "PCIe: RC%d: Failed to deregister event for BDF 0x%04x\n",