Hi Lucas and Mark, Looks like commit 9ce70d49fa80 ("spi: fix IDR collision on systems with both fixed and dynamic SPI bus numbers") causes the following regression at least for omaps. Reverting commit 9ce70d49fa80 fixes it. Any ideas? Seems it was also reported by the 0day kernel test robot on Saturday: https://www.spinics.net/lists/kernel/msg2624673.html Regards, Tony 8< ------------[ cut here ]------------ WARNING: CPU: 0 PID: 1 at ./include/linux/idr.h:113 spi_register_controller+0x81c/0x93c Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.14.0-rc4-next-20171016 #1377 Hardware name: Generic OMAP4 (Flattened Device Tree) [<c01112a0>] (unwind_backtrace) from [<c010d164>] (show_stack+0x10/0x14) [<c010d164>] (show_stack) from [<c086fd40>] (dump_stack+0xac/0xe0) [<c086fd40>] (dump_stack) from [<c0137ed0>] (__warn+0xd8/0x104) [<c0137ed0>] (__warn) from [<c0137ff0>] (warn_slowpath_null+0x20/0x28) [<c0137ff0>] (warn_slowpath_null) from [<c065ec74>] (spi_register_controller+0x81c/0x93c) [<c065ec74>] (spi_register_controller) from [<c065edc4>] (devm_spi_register_controller+0x30/0x70) [<c065edc4>] (devm_spi_register_controller) from [<c0662930>] (omap2_mcspi_probe+0x274/0x358) [<c0662930>] (omap2_mcspi_probe) from [<c05b7b10>] (platform_drv_probe+0x50/0xb0) [<c05b7b10>] (platform_drv_probe) from [<c05b5bf8>] (driver_probe_device+0x264/0x2ec) [<c05b5bf8>] (driver_probe_device) from [<c05b5d40>] (__driver_attach+0xc0/0xc4) [<c05b5d40>] (__driver_attach) from [<c05b3fe0>] (bus_for_each_dev+0x78/0xc0) [<c05b3fe0>] (bus_for_each_dev) from [<c05b5018>] (bus_add_driver+0xf8/0x208) [<c05b5018>] (bus_add_driver) from [<c05b6bd8>] (driver_register+0x78/0xf4) [<c05b6bd8>] (driver_register) from [<c0101e24>] (do_one_initcall+0x48/0x194) [<c0101e24>] (do_one_initcall) from [<c0c00f28>] (kernel_init_freeable+0x1fc/0x2c4) [<c0c00f28>] (kernel_init_freeable) from [<c0884830>] (kernel_init+0x8/0x110) [<c0884830>] (kernel_init) from [<c0108188>] (ret_from_fork+0x14/0x2c) ---[ end trace 9fd4ad3daaa4f7a3 ]--- ------------[ cut here ]------------ WARNING: CPU: 0 PID: 1 at drivers/spi/spi.c:2123 spi_register_controller+0x5c4/0x93c couldn't get idr Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 4.14.0-rc4-next-20171016 #1377 Hardware name: Generic OMAP4 (Flattened Device Tree) [<c01112a0>] (unwind_backtrace) from [<c010d164>] (show_stack+0x10/0x14) [<c010d164>] (show_stack) from [<c086fd40>] (dump_stack+0xac/0xe0) [<c086fd40>] (dump_stack) from [<c0137ed0>] (__warn+0xd8/0x104) [<c0137ed0>] (__warn) from [<c0137f3c>] (warn_slowpath_fmt+0x40/0x68) [<c0137f3c>] (warn_slowpath_fmt) from [<c065ea1c>] (spi_register_controller+0x5c4/0x93c) [<c065ea1c>] (spi_register_controller) from [<c065edc4>] (devm_spi_register_controller+0x30/0x70) [<c065edc4>] (devm_spi_register_controller) from [<c0662930>] (omap2_mcspi_probe+0x274/0x358) [<c0662930>] (omap2_mcspi_probe) from [<c05b7b10>] (platform_drv_probe+0x50/0xb0) [<c05b7b10>] (platform_drv_probe) from [<c05b5bf8>] (driver_probe_device+0x264/0x2ec) [<c05b5bf8>] (driver_probe_device) from [<c05b5d40>] (__driver_attach+0xc0/0xc4) [<c05b5d40>] (__driver_attach) from [<c05b3fe0>] (bus_for_each_dev+0x78/0xc0) [<c05b3fe0>] (bus_for_each_dev) from [<c05b5018>] (bus_add_driver+0xf8/0x208) [<c05b5018>] (bus_add_driver) from [<c05b6bd8>] (driver_register+0x78/0xf4) [<c05b6bd8>] (driver_register) from [<c0101e24>] (do_one_initcall+0x48/0x194) [<c0101e24>] (do_one_initcall) from [<c0c00f28>] (kernel_init_freeable+0x1fc/0x2c4) [<c0c00f28>] (kernel_init_freeable) from [<c0884830>] (kernel_init+0x8/0x110) [<c0884830>] (kernel_init) from [<c0108188>] (ret_from_fork+0x14/0x2c) ---[ end trace 9fd4ad3daaa4f7a4 ]--- omap2_mcspi: probe of 48098000.spi failed with error -22 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html