The condition register PCI_RCV_INTX is used in irq_mask(), irq_unmask() and irq_ack() callbacks. Accesses to register can occur at the same time without a lock. Add a lock into each callback to prevent the issue. Fixes: 7e6d5cd88a6f ("PCI: uniphier: Add UniPhier PCIe host controller support") Suggested-by: Pali Rohár <pali@xxxxxxxxxx> Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx> --- drivers/pci/controller/dwc/pcie-uniphier.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) The previous patch is as follows: https://lore.kernel.org/linux-pci/1629370566-29984-1-git-send-email-hayashi.kunihiko@xxxxxxxxxxxxx/ Changes in the previous patch: - Change the subject and commit message diff --git a/drivers/pci/controller/dwc/pcie-uniphier.c b/drivers/pci/controller/dwc/pcie-uniphier.c index ebe43e9..5075714 100644 --- a/drivers/pci/controller/dwc/pcie-uniphier.c +++ b/drivers/pci/controller/dwc/pcie-uniphier.c @@ -186,12 +186,17 @@ static void uniphier_pcie_irq_ack(struct irq_data *d) struct pcie_port *pp = irq_data_get_irq_chip_data(d); struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct uniphier_pcie_priv *priv = to_uniphier_pcie(pci); + unsigned long flags; u32 val; + raw_spin_lock_irqsave(&pp->lock, flags); + val = readl(priv->base + PCL_RCV_INTX); val &= ~PCL_RCV_INTX_ALL_STATUS; val |= BIT(irqd_to_hwirq(d) + PCL_RCV_INTX_STATUS_SHIFT); writel(val, priv->base + PCL_RCV_INTX); + + raw_spin_unlock_irqrestore(&pp->lock, flags); } static void uniphier_pcie_irq_mask(struct irq_data *d) @@ -199,12 +204,17 @@ static void uniphier_pcie_irq_mask(struct irq_data *d) struct pcie_port *pp = irq_data_get_irq_chip_data(d); struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct uniphier_pcie_priv *priv = to_uniphier_pcie(pci); + unsigned long flags; u32 val; + raw_spin_lock_irqsave(&pp->lock, flags); + val = readl(priv->base + PCL_RCV_INTX); val &= ~PCL_RCV_INTX_ALL_MASK; val |= BIT(irqd_to_hwirq(d) + PCL_RCV_INTX_MASK_SHIFT); writel(val, priv->base + PCL_RCV_INTX); + + raw_spin_unlock_irqrestore(&pp->lock, flags); } static void uniphier_pcie_irq_unmask(struct irq_data *d) @@ -212,12 +222,17 @@ static void uniphier_pcie_irq_unmask(struct irq_data *d) struct pcie_port *pp = irq_data_get_irq_chip_data(d); struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct uniphier_pcie_priv *priv = to_uniphier_pcie(pci); + unsigned long flags; u32 val; + raw_spin_lock_irqsave(&pp->lock, flags); + val = readl(priv->base + PCL_RCV_INTX); val &= ~PCL_RCV_INTX_ALL_MASK; val &= ~BIT(irqd_to_hwirq(d) + PCL_RCV_INTX_MASK_SHIFT); writel(val, priv->base + PCL_RCV_INTX); + + raw_spin_unlock_irqrestore(&pp->lock, flags); } static struct irq_chip uniphier_pcie_irq_chip = { -- 2.7.4