From f51af8a63c5f633b572d00319ecdfa31f266b8fb Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Tue, 27 Feb 2018 17:19:52 -0600 Subject: [PATCH] PCI/ASPM: Declare threshold_ns as u32, not u64 aspm_calc_l1ss_info() computes l1_2_threshold in microseconds as: l1_2_threshold = 2 + 4 + t_common_mode + t_power_on; where t_common_mode is at most 255us: PCI_L1SS_CAP_CM_RESTORE_TIME 0x0000ff00 <-- 8 bits; <256us and t_power_on is at most 31 * 100us = 3100us: PCI_L1SS_CAP_P_PWR_ON_VALUE 0x00f80000 <-- 5 bits; <32 PCI_L1SS_CAP_P_PWR_ON_SCALE 0x00030000 <-- *2us, *10us, or *100us So l1_2_threshold is at most 2 + 4 + 255 + 3100 = 3361, which means threshold_ns is at most 3361 * 1000 = 3361000, which easily fits in a u32. Declare threshold_ns as u32, not u64. This fixes a Coverity warning. Addresses-Coverity-ID: 1462501 Signed-off-by: Gustavo A. R. Silva [bhelgaas: changelog] Signed-off-by: Bjorn Helgaas Reviewed-by: Andy Shevchenko --- drivers/pci/pcie/aspm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 57feef2ecfe7..8633fc4e1c11 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -322,7 +322,7 @@ static u32 calc_l1ss_pwron(struct pci_dev *pdev, u32 scale, u32 val) static void encode_l12_threshold(u32 threshold_us, u32 *scale, u32 *value) { - u64 threshold_ns = threshold_us * 1000; + u32 threshold_ns = threshold_us * 1000; /* See PCIe r3.1, sec 7.33.3 and sec 6.18 */ if (threshold_ns < 32) {