On OpenWRT 5.4.42 kernel on an imx6, I'm seeing a kernel crash when loading builtin modules of igb driver and mv88e6xxx driver over PCI bus. I've searched for the messages in the kernel code and Google but its all over the place. What does this backtrace mean?
Modules linked in: [ 2.631594][ T28] CPU: 2 PID: 28 Comm: kworker/u8:1 Not tainted 5.4.42 #0 [ 2.631599][ T28] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) 2.670498][ T32] Workqueue: events_unbound async_run_entry_fn [ 2.676560][ T32] [<80016424>] (unwind_backtrace) from [<80012a84>] (show_stack+0x10/0x14) [ 2.685057][ T32] [<80012a84>] (show_stack) from [<8053cb30>] (dump_stack+0x90/0xa4) [ 2.693033][ T32] [<8053cb30>] (dump_stack) from [<800241fc>] (__warn+0xbc/0xd8) [ 2.700636][ T32] [<800241fc>] (__warn) from [<80024268>] (warn_slowpath_fmt+0x50/0x94) [ 2.708849][ T32] [<80024268>] (warn_slowpath_fmt) from [<8004331c>] (__request_module+0xac/0x37c) [ 2.718020][ T32] [<8004331c>] (__request_module) from [<802eaeac>] (phy_request_driver_module+0x118/0x158) [ 2.727967][ T32] [<802eaeac>] (phy_request_driver_module) from [<802ec4ac>] (phy_device_create+0x1e4/0x204) [ 2.737997][ T32] [<802ec4ac>] (phy_device_create) from [<802ec628>] (get_phy_device+0x15c/0x1b0) [ 2.747098][ T32] [<802ec628>] (get_phy_device) from [<803d7ab4>] (of_mdiobus_register_phy+0x74/0x170) [ 2.756615][ T32] [<803d7ab4>] (of_mdiobus_register_phy) from [<803d8040>] (of_mdiobus_register+0x120/0x32c) [ 2.766665][ T32] [<803d8040>] (of_mdiobus_register) from [<802ef248>] (mv88e6xxx_mdio_register+0xdc/0x190) [ 2.776617][ T32] [<802ef248>] (mv88e6xxx_mdio_register) from [<802f10ac>] (mv88e6xxx_probe+0x618/0x714) [ 2.786305][ T32] [<802f10ac>] (mv88e6xxx_probe) from [<802edaf8>] (mdio_probe+0x30/0x54) [ 2.794699][ T32] [<802edaf8>] (mdio_probe) from [<8027a034>] (really_probe+0x1f0/0x364) [ 2.802996][ T32] [<8027a034>] (really_probe) from [<8027a328>] (driver_probe_device+0x60/0x170) [ 2.811986][ T32] [<8027a328>] (driver_probe_device) from [<802785c0>] (bus_for_each_drv+0x70/0x94) [ 2.821231][ T32] [<802785c0>] (bus_for_each_drv) from [<80279dd4>] (__device_attach+0xb4/0x11c) [ 2.830218][ T32] [<80279dd4>] (__device_attach) from [<802791d8>] (bus_probe_device+0x84/0x8c) [ 2.839117][ T32] [<802791d8>] (bus_probe_device) from [<802768d0>] (device_add+0x36c/0x614) [ 2.847759][ T32] [<802768d0>] (device_add) from [<802edb9c>] (mdio_device_register+0x24/0x48) [ 2.856582][ T32] [<802edb9c>] (mdio_device_register) from [<803d81b4>] (of_mdiobus_register+0x294/0x32c) [ 2.866367][ T32] [<803d81b4>] (of_mdiobus_register) from [<8032ccc8>] (igb_probe+0x1088/0x13cc) [ 2.875385][ T32] [<8032ccc8>] (igb_probe) from [<8021f010>] (pci_device_probe+0xd4/0x15c) [ 2.883862][ T32] [<8021f010>] (pci_device_probe) from [<8027a034>] (really_probe+0x1f0/0x364) [ 2.892676][ T32] [<8027a034>] (really_probe) from [<8027a328>] (driver_probe_device+0x60/0x170) [ 2.901663][ T32] [<8027a328>] (driver_probe_device) from [<802785c0>] (bus_for_each_drv+0x70/0x94) [ 2.910910][ T32] [<802785c0>] (bus_for_each_drv) from [<80279dd4>] (__device_attach+0xb4/0x11c) [ 2.919917][ T32] [<80279dd4>] (__device_attach) from [<80213bbc>] (pci_bus_add_device+0x44/0x90) [ 2.928995][ T32] [<80213bbc>] (pci_bus_add_device) from [<80213c34>] (pci_bus_add_devices+0x2c/0x70) [ 2.938420][ T32] [<80213c34>] (pci_bus_add_devices) from [<80213c68>] (pci_bus_add_devices+0x60/0x70) [ 2.948007][ T32] ---[ end trace c8de08d4ca07a3ea ]--- with this device tree : &pcie { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_pcie>; reset-gpio =<&reset_ic 0 1>; child-reset-gpios = <&reset_ic 3 1 &reset_ic 2 1 &reset_ic 1 1>; #gpio-cells = <3>; status = "okay"; fsl,max-link-speed = <2>; /* * PCI bridge: PLX Technology, Inc. PEX 8605 PCI Express 4-port Gen2 Switch * Port 0 to CPU, Port 1 to igb and ports 2 and 3 are accessible through * the half and full size mini PCIe slots on the board. */ pcie@1,0 { /* Connection to CPU */ status = "okay"; fsl,max-link-speed = <2>; }; pcie@2,1 { /* Connection to Intel Gigabit Ethernet Controller*/ status = "okay"; fsl,max-link-speed = <1>; pcie@3,0 { /* The igb */ status = "okay"; fsl,max-link-speed = <1>; eth0: igb0 { compatible = "intel,igb"; /*pinctrl-names = "default"; pinctrl-0 = <&pinctrl_enet>;*/ phy-mode = "mii"; phy-handle = <ð0>; phy-reset-gpios = <&reset_ic 4 GPIO_ACTIVE_LOW>; phy-reset-duration = <100>; status = "okay"; mdio { #address-cells = <1>; #size-cells = <0>; status = "okay"; switch: switch@0 { compatible ="marvell,mv88e6085"; reg = <0>; dsa,member = <0 0>; eeprom-length = <512>; interrupt-parent = <&gpio2>; interrupts = <31IRQ_TYPE_LEVEL_LOW>; interrupt-controller; #interrupt-cells = <2>; ports { #address-cells = <1>; #size-cells = <0>; port@0 { reg = <0>; label = "port0"; phy-handle = <&switchphy0>; }; port@1 { reg = <1>; label = "port1"; phy-handle = <&switchphy1>; }; port@2 { reg = <2>; label = "port0"; phy-handle = <&switchphy2>; }; port@5 { reg = <5>; label = "cpu"; ethernet = <ð0>; }; }; mdio { #address-cells = <1>; #size-cells = <0>; switchphy0:switchphy@0 { reg = <0>; interrupt-parent = <&switch>; interrupts =<0 IRQ_TYPE_LEVEL_HIGH>; }; switchphy1:switchphy@1 { reg = <1>; interrupt-parent = <&switch>; interrupts =<1 IRQ_TYPE_LEVEL_HIGH>; }; switchphy2:switchphy@2 { reg = <2>; interrupt-parent = <&switch>; interrupts =<2 IRQ_TYPE_LEVEL_HIGH>; }; }; }; };