From 1c6bca6d75bca2cc47b5eafb9f7f16e368ffbeca Mon Sep 17 00:00:00 2001 From: Shahar S Matityahu Date: Mon, 15 Apr 2019 14:43:04 +0300 Subject: iwlwifi: don't panic in error path on non-msix systems The driver uses msix causes-register to handle both msix and non msix interrupts when performing sync nmi. On devices that do not support msix this register is unmapped and accessing it causes a kernel panic. Solve this by differentiating the two cases and accessing the proper causes-register in each case. Reported-by: Michal Hocko Signed-off-by: Shahar S Matityahu Signed-off-by: Luca Coelho --- drivers/net/wireless/intel/iwlwifi/pcie/trans.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c index 79c1dc05f948..c4375b868901 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c @@ -3644,20 +3644,27 @@ out_no_pci: void iwl_trans_pcie_sync_nmi(struct iwl_trans *trans) { + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); unsigned long timeout = jiffies + IWL_TRANS_NMI_TIMEOUT; + u32 inta_addr, sw_err_bit; + + if (trans_pcie->msix_enabled) { + inta_addr = CSR_MSIX_HW_INT_CAUSES_AD; + sw_err_bit = MSIX_HW_INT_CAUSES_REG_SW_ERR; + } else { + inta_addr = CSR_INT; + sw_err_bit = CSR_INT_BIT_SW_ERR; + } iwl_disable_interrupts(trans); iwl_force_nmi(trans); while (time_after(timeout, jiffies)) { - u32 inta_hw = iwl_read32(trans, - CSR_MSIX_HW_INT_CAUSES_AD); + u32 inta_hw = iwl_read32(trans, inta_addr); /* Error detected by uCode */ - if (inta_hw & MSIX_HW_INT_CAUSES_REG_SW_ERR) { + if (inta_hw & sw_err_bit) { /* Clear causes register */ - iwl_write32(trans, CSR_MSIX_HW_INT_CAUSES_AD, - inta_hw & - MSIX_HW_INT_CAUSES_REG_SW_ERR); + iwl_write32(trans, inta_addr, inta_hw & sw_err_bit); break; } -- cgit v1.2.3