Hi, On 3/19/20 5:16 PM, Marc Zyngier wrote: > Hi Eric, > > On 2020-03-19 15:43, Auger Eric wrote: >> Hi Marc, >> >> On 3/19/20 4:21 PM, Marc Zyngier wrote: >>> Hi Eric, > > [...] > >>>> The patch looks good to me but I am now lost about how we retrieve the >>>> pending stat of other hw mapped interrupts. Looks we use >>>> irq->pending_latch always. Is that correct? >>> >>> Correct. GICv4.0 doesn't give us an architectural way to look at the >>> vLPI pending state (there isn't even a guarantee about when the GIC >>> will stop writing to memory, if it ever does). >>> >>> With GICv4.1, you can introspect the HW state for SGIs. You can also >>> look at the vLPI state by peeking at the virtual pending table, but >>> you'd need to unmap the VPE first, which I obviously don't want to do >>> for this debug interface, specially as it can be used whilst the guest >>> is up and running. >> OK for vLPIs, what about other HW mapped IRQs (arch timer?) > > Different kind of HW. With those, the injection is still virtual, so the > SW pending bit is still very much valid. You can actually try and make > the timer interrupt pending, it should show up. > > What the irq->hw bit means is "this virtual interrupt is somehow related > to the host_irq". How this is interpreted is completely context-dependent. OK thank you for refreshing my memories ;-) Eric > > Thanks, > > M. _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
