Hi Alex, just ran into some corner case with my reanimated IRQ sharing patches that may affect vfio as well: How are vfio_enable/disable_intx synchronized against all other possible spots that call pci_block_user_cfg_access? I hit the recursion bug check in pci_block_user_cfg_access with my code which takes the user_cfg lock like vfio does. It likely races with pci_reset_function here - and should do so in vfio as well. Just taking some lock would mean having to run pci_reset_function with IRQs disabled to synchronize with the IRQ handler (not sure if that is possible at all). Alternatively, we would have to disable the interrupt line or deregister the IRQ while resetting. Or we perform INTx mask manipulation in an unsynchronized fashion, resolving races with user space differently (still need to think about this option). Any other thoughts? Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
