Worked on the geerlingguy/linux repository to address a critical deadlock issue in the PCI/MSI driver path, focusing on kernel stability under high I/O load. The engineering effort centered on fixing recursive locking in the pci_msix_write_tph_tag function by reordering lock acquisition and function calls, ensuring the MSI descriptor mutex is obtained after the virtual IRQ. This approach improved concurrency control and reduced the risk of system hangs. The work demonstrated expertise in kernel development and device driver maintenance using C, with an emphasis on maintainable code changes that enhance system reliability and enforce proper lock-order discipline in complex kernel subsystems.