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So I think on the one hand, we should make the module > parameter read-only; on the other hand, we could also expose this > information in the PCI core device's sysfs directory =E2=80=94 read-only = as well=20 > for now, > or perhaps there's an even better approach? nointxmask never took effect immediately, it was at best setup when the device is opened. We could support that behavior again, but it's actually more limiting, all devices supporting INTx would latch nointxmask on open and therefore require an exclusive interrupt. I've encountered this in debugging, where it's more useful to isolate nointxmask to a single device rather than modify the VM config to remove devices or unload host drivers to free IRQ lines. disable_idle_d3 manages the power state of unused devices, where setting disable_idle_d3 never woke devices that were already bound and idle, it only affected future use of low power states. I do still see value in directing this behavior to specific devices, it's a runtime diagnostic versus directing users to set quirk flags and recompile their kernel. Therefore, neither of these are really improved by making the module parameter itself read-only. Given these are largely diagnostic, debugfs would be the more natural way to expose it versus sysfs. We already have some support for debugfs for exposing migration features and state. This might be a good idea, but I'd also argue it's more of a feature scope, whereas I'd really like to get the Fixes: and behavior restoration scoped change in tree asap. Thanks, Alex