From f1c853b53cf2b49eb32791072c8a8ee04f122f58 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Sun, 12 Feb 2012 14:28:20 +0000 Subject: [PATCH] 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 Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/platforms/powernv/pci.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c index a70bc1e385eb..f92b9ef7340e 100644 --- a/arch/powerpc/platforms/powernv/pci.c +++ b/arch/powerpc/platforms/powernv/pci.c @@ -52,32 +52,38 @@ static int pnv_msi_check_device(struct pci_dev* pdev, int nvec, int type) static unsigned int pnv_get_one_msi(struct pnv_phb *phb) { - unsigned int id; + unsigned long flags; + unsigned int id, rc; + + spin_lock_irqsave(&phb->lock, flags); - spin_lock(&phb->lock); 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) -- 2.34.1