KVM: PPC: Book3S HV: Workaround POWER9 DD1.0 bug causing IPB bit loss
authorBenjamin Herrenschmidt <benh@kernel.crashing.org>
Fri, 18 Aug 2017 02:10:52 +0000 (12:10 +1000)
committerPaul Mackerras <paulus@ozlabs.org>
Thu, 24 Aug 2017 10:01:39 +0000 (20:01 +1000)
commit2c4fb78f78b6e420604ee1b05bdfb5c1d637869f
treebb24b5693f1c1770030c1f880684e1b130dc8262
parentbd0fdb191c8523a9126bb14ac1b22cb47698ebf5
KVM: PPC: Book3S HV: Workaround POWER9 DD1.0 bug causing IPB bit loss

This adds a workaround for a bug in POWER9 DD1 chips where changing
the CPPR (Current Processor Priority Register) can cause bits in the
IPB (Interrupt Pending Buffer) to get lost.  Thankfully it only
happens when manually manipulating CPPR which is quite rare.  When it
does happen it can cause interrupts to be delayed or lost.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
arch/powerpc/kvm/book3s_xive_template.c