On Mon, Nov 13, 2017 at 11:04 AM, Dmitry Torokhov <dmitry.torok...@gmail.com> wrote: > > On Mon, Nov 13, 2017 at 10:18:35AM -0800, Randy Dunlap wrote: > > On 11/13/2017 06:41 AM, Guenter Roeck wrote: > > > > > > > > > On Sun, Nov 12, 2017 at 10:36 PM, Randy Dunlap <rdun...@infradead.org > > > <mailto:rdun...@infradead.org>> wrote: > > > > > > sysfs: cannot create duplicate filename '/devices/platform/vpd' > > > > > > on the second load of this driver. I.e., > > > > > > modprobe vpd-sysfs > > > rmmod vpd-sysfs > > > modprobe vpd-sysfs > > > [boom] > > > > > > Neither the platform device nor the platform driver driver are ever > > > unregistered, so this isn't entirely surprising. I'll try to reproduce > > > and send a patch. > > > > > > Seems to be a common theme: > > > > google> grep --color=never "platform.*register" *.c > > coreboot_table-acpi.c: return > > platform_driver_register(&coreboot_table_acpi_driver); > > coreboot_table-of.c: return > > platform_driver_register(&coreboot_table_of_driver); > > These are not unloadable (for better or worse) - they do not have > module_exit() in them. > > > > > gsmi.c: gsmi_dev.pdev = platform_device_register_full(&gsmi_dev_info); > > gsmi.c: platform_device_unregister(gsmi_dev.pdev); > > gsmi.c: platform_device_unregister(gsmi_dev.pdev); > > [looks good] > > > > memconsole-coreboot.c: pdev = > > platform_device_register_simple("memconsole", -1, NULL, 0); > > memconsole-coreboot.c: platform_driver_register(&memconsole_driver); > > Same here: not unloadable. > > > > > vpd.c: pdev = platform_device_register_simple("vpd", -1, NULL, 0); > > vpd.c: platform_driver_register(&vpd_driver); > > Arguably this should not even be a platform driver, there is no hardware > behind it. I was planning on purring some notifiers into coreboot table > driver and using notifiers to attach vpd to them. -ENOTIME though. > Two options for now: clean it up and make it unloadable, or make it bool and drop the exit function. Any preference ?
The problem is easy to reproduce even with the driver is built into the kernel with a simple unbind/bind sequence. And after the unbind, it is easy to crash the system since the sysfs attributes are still there. Guenter
