In gicv3_redist_lpi_pending() we update cs->hpplpi to indicate the new highest priority pending LPI after changing the requested LPI pending bit. However the overall highest priority pending interrupt information won't be updated unless we call gicv3_redist_update(). We do that from the callsite in gicv3-redist_process_lpi(), but not from the callsite in icc_activate_irq(). The effect is that when the guest acknowledges an LPI by reading ICC_IAR1_EL1, we mark it as not pending in the data structure but still leave it in cs->hppi so will offer it to the guest again.
The effect is that if we are using an emulated GICv3 and ITS and using devices which use LPIs (ie PCI devices) then Linux will complain "irq 54: nobody cared" and then hang (probably because the stale bogus interrupt info meant we never tried to deliver some other real interrupt). Add the missing gicv3_redist_update() call. Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> --- Marked for-6.2 because this is a bug fix to the ITS support which is new in this release. At least for me this is necessary to boot Debian on the virt board, since the ITS is default-enabled. The failure seemed to be somewhat intermittent; I haven't bothered to try to work out why. hw/intc/arm_gicv3_cpuif.c | 1 + 1 file changed, 1 insertion(+) diff --git a/hw/intc/arm_gicv3_cpuif.c b/hw/intc/arm_gicv3_cpuif.c index 3fe5de8ad7d..2d9f2ad2b6c 100644 --- a/hw/intc/arm_gicv3_cpuif.c +++ b/hw/intc/arm_gicv3_cpuif.c @@ -906,6 +906,7 @@ static void icc_activate_irq(GICv3CPUState *cs, int irq) gicv3_update(cs->gic, irq, 1); } else { gicv3_redist_lpi_pending(cs, irq, 0); + gicv3_redist_update(cs); } } -- 2.25.1