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We're using pci_irq_vector() to obtain the interrupt number and then bind it to the CPU start perf under the protection of spinlock in pmu::start(). pci_irq_vector() might sleep since [1] because it will call msi_domain_get_virq() to get the MSI interrupt number and it needs to acquire dev->msi.data->mutex. Getting a mutex will sleep on contention. So use pci_irq_vector() in an atomic context is problematic. This patch cached the interrupt number in the probe() and uses the cached data instead to avoid potential sleep. [1] commit82ff8e6b78("PCI/MSI: Use msi_get_virq() in pci_get_vector()") Fixes:ff0de066b4("hwtracing: hisi_ptt: Add trace function support for HiSilicon PCIe Tune and Trace device") Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20230621092804.15120-6-yangyicong@huawei.com