From e22051e7c9f7091256c18829433c6eedaca799a0 Mon Sep 17 00:00:00 2001 From: Jon Hunter Date: Fri, 18 Jun 2021 17:02:19 +0100 Subject: [PATCH] PCI: tegra194: Fix tegra_pcie_ep_raise_msi_irq() ill-defined shift [ Upstream commit f67092eff2bd40650aad54a1a1910160f41d864a ] tegra_pcie_ep_raise_msi_irq() shifted a signed 32-bit value left by 31 bits. The behavior of this is implementation-defined. Replace the shift by BIT(), which is well-defined. Found by cppcheck: $ cppcheck --enable=all drivers/pci/controller/dwc/pcie-tegra194.c Checking drivers/pci/controller/dwc/pcie-tegra194.c ... drivers/pci/controller/dwc/pcie-tegra194.c:1829:23: portability: Shifting signed 32-bit value by 31 bits is implementation-defined behaviour. See condition at line 1826. [shiftTooManyBitsSigned] appl_writel(pcie, (1 << irq), APPL_MSI_CTRL_1); ^ [bhelgaas: commit log] Link: https://lore.kernel.org/r/20210618160219.303092-1-jonathanh@nvidia.com Fixes: c57247f940e8 ("PCI: tegra: Add support for PCIe endpoint mode in Tegra194") Signed-off-by: Jon Hunter Signed-off-by: Lorenzo Pieralisi Signed-off-by: Bjorn Helgaas Signed-off-by: Sasha Levin --- drivers/pci/controller/dwc/pcie-tegra194.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c index d788f4d..506f6a2 100644 --- a/drivers/pci/controller/dwc/pcie-tegra194.c +++ b/drivers/pci/controller/dwc/pcie-tegra194.c @@ -1841,7 +1841,7 @@ static int tegra_pcie_ep_raise_msi_irq(struct tegra_pcie_dw *pcie, u16 irq) if (unlikely(irq > 31)) return -EINVAL; - appl_writel(pcie, (1 << irq), APPL_MSI_CTRL_1); + appl_writel(pcie, BIT(irq), APPL_MSI_CTRL_1); return 0; } -- 2.7.4