[PATCH v4 04/12] iwlegacy: Check if pcie_capability_read_*() reads ~0
From: Saheed O. Bolarinwa <hidden>
Date: 2020-07-31 12:02:34
Also in:
linux-kernel-mentees, linux-pci, linux-wireless, lkml
Subsystem:
intel wireless 3945abg/bg, 4965agn (iwlegacy), the rest · Maintainers:
Stanislaw Gruszka, Linus Torvalds
On failure pcie_capability_read_dword() sets it's last parameter, val to 0. However, with Patch 12/12, it is possible that val is set to ~0 on failure. This would introduce a bug because (x & x) == (~0 & x). Since ~0 is an invalid value here, Add an extra check for ~0 to the if condition to ensure success. Suggested-by: Bjorn Helgaas <redacted> Signed-off-by: Saheed O. Bolarinwa <redacted> --- drivers/net/wireless/intel/iwlegacy/common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/wireless/intel/iwlegacy/common.c b/drivers/net/wireless/intel/iwlegacy/common.c
index 348c17ce72f5..659027563260 100644
--- a/drivers/net/wireless/intel/iwlegacy/common.c
+++ b/drivers/net/wireless/intel/iwlegacy/common.c@@ -4287,7 +4287,7 @@ il_apm_init(struct il_priv *il) */ if (il->cfg->set_l0s) { pcie_capability_read_word(il->pci_dev, PCI_EXP_LNKCTL, &lctl); - if (lctl & PCI_EXP_LNKCTL_ASPM_L1) { + if ((lctl != (u16)~0) && (lctl & PCI_EXP_LNKCTL_ASPM_L1)) { /* L1-ASPM enabled; disable(!) L0S */ il_set_bit(il, CSR_GIO_REG, CSR_GIO_REG_VAL_L0S_ENABLED);
--
2.18.4