From dc1c4165d189350cb51bdd3057deb6ecd164beda Mon Sep 17 00:00:00 2001 From: =?utf8?q?C=C3=A9dric=20Le=20Goater?= Date: Tue, 12 Dec 2017 12:02:04 +0000 Subject: [PATCH] KVM: PPC: Book3S: fix XIVE migration of pending interrupts MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit When restoring a pending interrupt, we are setting the Q bit to force a retrigger in xive_finish_unmask(). But we also need to force an EOI in this case to reach the same initial state : P=1, Q=0. This can be done by not setting 'old_p' for pending interrupts which will inform xive_finish_unmask() that an EOI needs to be sent. Fixes: 5af50993850a ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller") Cc: stable@vger.kernel.org # v4.12+ Suggested-by: Benjamin Herrenschmidt Signed-off-by: Cédric Le Goater Reviewed-by: Laurent Vivier Tested-by: Laurent Vivier Signed-off-by: Michael Ellerman --- arch/powerpc/kvm/book3s_xive.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c index bf457843e032..b5e6d227a034 100644 --- a/arch/powerpc/kvm/book3s_xive.c +++ b/arch/powerpc/kvm/book3s_xive.c @@ -1558,7 +1558,7 @@ static int xive_set_source(struct kvmppc_xive *xive, long irq, u64 addr) /* * Restore P and Q. If the interrupt was pending, we - * force both P and Q, which will trigger a resend. + * force Q and !P, which will trigger a resend. * * That means that a guest that had both an interrupt * pending (queued) and Q set will restore with only @@ -1566,7 +1566,7 @@ static int xive_set_source(struct kvmppc_xive *xive, long irq, u64 addr) * is perfectly fine as coalescing interrupts that haven't * been presented yet is always allowed. */ - if (val & KVM_XICS_PRESENTED || val & KVM_XICS_PENDING) + if (val & KVM_XICS_PRESENTED && !(val & KVM_XICS_PENDING)) state->old_p = true; if (val & KVM_XICS_QUEUED || val & KVM_XICS_PENDING) state->old_q = true; -- 2.39.5