[Skiboot] [PATCH] phb3: Lock the PHB on set_xive callbacks

[Benjamin Herrenschmidt]

Those are called by the interrupts core and thus skip the locking
implicit in the PCI opal calls.

However IODA table access can be racy, so make sure we lock the PHB.

Signed-off-by: Benjamin Herrenschmidt 
---
 hw/phb3.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/hw/phb3.c b/hw/phb3.c
index 52b30c2..9c97b88 100644
--- a/hw/phb3.c
+++ b/hw/phb3.c
@@ -1703,6 +1703,8 @@ static int64_t phb3_msi_set_xive(struct irq_source *is, uint32_t isn,
 	    ive_num > PHB3_MSI_IRQ_MAX)
 		return OPAL_PARAMETER;
 
+	phb_lock(&p->phb);
+
 	/*
 	 * We need strip the link from server. As Milton told
 	 * me, the server is assigned as follows and the left
@@ -1764,6 +1766,8 @@ static int64_t phb3_msi_set_xive(struct irq_source *is, uint32_t isn,
 		out_be64(p->regs + PHB_IVC_UPDATE, ivc);
 	}
 
+	phb_unlock(&p->phb);
+
 	return OPAL_SUCCESS;
 }
 
@@ -1814,6 +1818,8 @@ static int64_t phb3_lsi_set_xive(struct irq_source *is, uint32_t isn,
 	lxive = SETFIELD(IODA2_LXIVT_SERVER, 0ul, server);
 	lxive = SETFIELD(IODA2_LXIVT_PRIORITY, lxive, prio);
 
+	phb_lock(&p->phb);
+
 	/*
 	 * We cache the arguments because we have to mangle
 	 * it in order to hijack 3 bits of priority to extend
@@ -1829,6 +1835,8 @@ static int64_t phb3_lsi_set_xive(struct irq_source *is, uint32_t isn,
 	lxive = SETFIELD(IODA2_LXIVT_PRIORITY, lxive, prio);
 	out_be64(p->regs + PHB_IODA_DATA0, lxive);
 
+	phb_unlock(&p->phb);
+
 	return OPAL_SUCCESS;
 }