On 12/7/21 10:44, Damien Hedde wrote:
According to the "Arm Generic Interrupt Controller Architecture
Specification GIC architecture version 3 and 4" (version G: page 345
for aarch64 or 509 for aarch32):
LRENP bit of ICH_MISR is set when ICH_HCR.LRENPIE==1 and
ICH_HCR.EOIcount is non-zero.
When only LRENPIE was set (and EOI count was zero), the LRENP bit was
wrongly set and MISR value was wrong.
As an additional consequence, if an hypervisor set ICH_HCR.LRENPIE,
the maintenance interrupt was constantly fired. It happens since patch
9cee1efe92 ("hw/intc: Set GIC maintenance interrupt level to only 0 or 1")
which fixed another bug about maintenance interrupt (most significant
bits of misr, including this one, were ignored in the interrupt trigger).
Fixes: 83f036fe3d ("hw/intc/arm_gicv3: Add accessors for ICH_ system registers")
This commit predates 6.1 release, so technically this is not
a regression for 6.2.