powerpc/powernv: Disable interrupts while taking phb->lock
We need to disable interrupts when taking the phb->lock. Otherwise
we could deadlock with pci_lock taken from an interrupt.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
index a70bc1e..f92b9ef 100644
--- a/arch/powerpc/platforms/powernv/pci.c
+++ b/arch/powerpc/platforms/powernv/pci.c
@@ -52,32 +52,38 @@
static unsigned int pnv_get_one_msi(struct pnv_phb *phb)
{
- unsigned int id;
+ unsigned long flags;
+ unsigned int id, rc;
- spin_lock(&phb->lock);
+ spin_lock_irqsave(&phb->lock, flags);
+
id = find_next_zero_bit(phb->msi_map, phb->msi_count, phb->msi_next);
if (id >= phb->msi_count && phb->msi_next)
id = find_next_zero_bit(phb->msi_map, phb->msi_count, 0);
if (id >= phb->msi_count) {
- spin_unlock(&phb->lock);
- return 0;
+ rc = 0;
+ goto out;
}
__set_bit(id, phb->msi_map);
- spin_unlock(&phb->lock);
- return id + phb->msi_base;
+ rc = id + phb->msi_base;
+out:
+ spin_unlock_irqrestore(&phb->lock, flags);
+ return rc;
}
static void pnv_put_msi(struct pnv_phb *phb, unsigned int hwirq)
{
+ unsigned long flags;
unsigned int id;
if (WARN_ON(hwirq < phb->msi_base ||
hwirq >= (phb->msi_base + phb->msi_count)))
return;
id = hwirq - phb->msi_base;
- spin_lock(&phb->lock);
+
+ spin_lock_irqsave(&phb->lock, flags);
__clear_bit(id, phb->msi_map);
- spin_unlock(&phb->lock);
+ spin_unlock_irqrestore(&phb->lock, flags);
}
static int pnv_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)