On 08/03/2021 22.31, Marc Zyngier wrote:
+ if ((read_sysreg_s(SYS_ICH_HCR_EL2) & ICH_HCR_EN) && + read_sysreg_s(SYS_ICH_MISR_EL2) != 0) { + pr_err("vGIC IRQ fired, disabling.\n");Please add a _ratelimited here. Whilst debugging KVM on this machine, I ended up with this firing at such a rate that it was impossible to do anything useful. Ratelimiting it allowed me to pinpoint the problem.
Ouch. Done for v4.
+static void aic_fiq_eoi(struct irq_data *d) +{ + /* We mask to ack (where we can), so we need to unmask at EOI. */ + if (!irqd_irq_disabled(d) && !irqd_irq_masked(d))Ah, be careful here: irqd_irq_masked() doesn't do what you think it does for per-CPU interrupts. It's been on my list to fix for the rVIC implementation, but I never got around to doing it, and all decent ICs hide this from SW by having a HW-managed mask, similar to what is on the IRQ side. I can see two possibilities: - you can track the masked state directly and use that instead of these predicates - you can just drop the masking altogether as this is only useful to a hosted hypervisor (KVM), which will have to do its own masking behind the scenes anyway
Since you're using the masking in KVM after all, I'm tracking the mask state in a percpu variable now. Also folded in your two minor bugfixes from the KVM series. Cheers!
-- Hector Martin ([email protected]) Public Key: https://mrcn.st/pub
