[PATCH AUTOSEL 5.4 13/37] KVM: PPC: Book3S HV: XICS: Fix mapping of passthrough interrupts

[Sasha Levin]

From: Cédric Le Goater <clg@xxxxxxxx>

[ Upstream commit 1753081f2d445f9157550692fcc4221cd3ff0958 ]

PCI MSIs now live in an MSI domain but the underlying calls, which
will EOI the interrupt in real mode, need an HW IRQ number mapped in
the XICS IRQ domain. Grab it there.

Signed-off-by: Cédric Le Goater <clg@xxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210701132750.1475580-31-clg@xxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/powerpc/kvm/book3s_hv.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index bba358f13471..dc897dff8eb9 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -5020,6 +5020,7 @@ static int kvmppc_set_passthru_irq(struct kvm *kvm, int host_irq, int guest_gsi)
 	struct kvmppc_passthru_irqmap *pimap;
 	struct irq_chip *chip;
 	int i, rc = 0;
+	struct irq_data *host_data;
 
 	if (!kvm_irq_bypass)
 		return 1;
@@ -5084,7 +5085,14 @@ static int kvmppc_set_passthru_irq(struct kvm *kvm, int host_irq, int guest_gsi)
 	 * the KVM real mode handler.
 	 */
 	smp_wmb();
-	irq_map->r_hwirq = desc->irq_data.hwirq;
+
+	/*
+	 * The 'host_irq' number is mapped in the PCI-MSI domain but
+	 * the underlying calls, which will EOI the interrupt in real
+	 * mode, need an HW IRQ number mapped in the XICS IRQ domain.
+	 */
+	host_data = irq_domain_get_irq_data(irq_get_default_host(), host_irq);
+	irq_map->r_hwirq = (unsigned int)irqd_to_hwirq(host_data);
 
 	if (i == pimap->n_mapped)
 		pimap->n_mapped++;
@@ -5092,7 +5100,7 @@ static int kvmppc_set_passthru_irq(struct kvm *kvm, int host_irq, int guest_gsi)
 	if (xics_on_xive())
 		rc = kvmppc_xive_set_mapped(kvm, guest_gsi, desc);
 	else
-		kvmppc_xics_set_mapped(kvm, guest_gsi, desc->irq_data.hwirq);
+		kvmppc_xics_set_mapped(kvm, guest_gsi, irq_map->r_hwirq);
 	if (rc)
 		irq_map->r_hwirq = 0;
 
-- 
2.30.2