Divide-by-zero error in qed_hw_get_nvm_info()
From: Kyungwook Boo <hidden>
Date: 2025-03-03 06:41:00
Also in:
lkml
Hello, It seems that qed_hw_info_port_num() reads the value of num_ports from MMIO and then qed_hw_get_nvm_info() performs a division opertation using this value, which could lead to a divide-by-zero error. The following is a call stack example: qed_probe ├── qed_hw_prepare │ ├── qed_hw_prepare_single │ │ ├── qed_get_hw_info │ │ │ ├── qed_hw_info_port_num │ │ │ │ ├── qed_rd (MMIO read: num_ports) │ │ │ ├── qed_hw_get_nvm_info │ │ │ │ ├── MFW_PORT (uses num_ports in modulo) In qed_hw_info_port_num(), cdev->num_ports is read from MMIO: cdev->num_ports = (u8)qed_rd(p_hwfn, p_ptt, addr); This value is then used for modulo operation in qed_hw_get_nvm_info(): port_cfg_addr = MCP_REG_SCRATCH + nvm_cfg1_offset + offsetof(struct nvm_cfg1, port[MFW_PORT(p_hwfn)]); // #define MFW_PORT(_p_hwfn) ((_p_hwfn)->abs_pf_id % \ // qed_device_num_ports((_p_hwfn)->cdev)) Could you check this? Best regards, Kyungwook Boo