On Mon, Nov 13, 2017 at 12:14:41PM -0800, Guenter Roeck wrote: > The sysfs warning, yes. However, after unbinding and rebinding the > driver, "cat /sys/firmware/vpd/rw_raw" will result in a crash. > > Sequence: > > echo vpd > /sys/bus/platform/drivers/vpd/unbind > echo vpd > /sys/bus/platform/drivers/vpd/bind # <-- nasty message > > cat /sys/firmware/vpd/rw_raw # <-- crash
I'd disable unbind (.suppress_bind_attrs = true) and commented out unload for now. And then looked into fixing properly. > > Guenter > > On Mon, Nov 13, 2017 at 11:23 AM, Greg Kroah-Hartman > <gre...@linuxfoundation.org> wrote: > > On Mon, Nov 13, 2017 at 11:09:21AM -0800, Guenter Roeck wrote: > >> 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. > > > > The kernel should not 'crash', just spit out a nasty warning, right? > > > > thanks, > > > > greg k-h -- Dmitry
