android_kernel_xiaomi_sm8450/drivers/uio
Alexandre Belloni ae61cf5b99 uio: ensure class is registered before devices
When both uio and the uio drivers are built in the kernel, it is possible
for a driver to register devices before the uio class is registered.

This may result in a NULL pointer dereference later on in
get_device_parent() when accessing the class glue_dirs spinlock.

The trace looks like that:

Unable to handle kernel NULL pointer dereference at virtual address 00000140
[...]
[<ffff0000089cc234>] _raw_spin_lock+0x14/0x48
[<ffff0000084f56bc>] device_add+0x154/0x6a0
[<ffff0000084f5e48>] device_create_groups_vargs+0x120/0x128
[<ffff0000084f5edc>] device_create+0x54/0x60
[<ffff0000086e72c0>] __uio_register_device+0x120/0x4a8
[<ffff000008528b7c>] jaguar2_pci_probe+0x2d4/0x558
[<ffff0000083fc18c>] local_pci_probe+0x3c/0xb8
[<ffff0000083fd81c>] pci_device_probe+0x11c/0x180
[<ffff0000084f88bc>] driver_probe_device+0x22c/0x2d8
[<ffff0000084f8a24>] __driver_attach+0xbc/0xc0
[<ffff0000084f69fc>] bus_for_each_dev+0x4c/0x98
[<ffff0000084f81b8>] driver_attach+0x20/0x28
[<ffff0000084f7d08>] bus_add_driver+0x1b8/0x228
[<ffff0000084f93c0>] driver_register+0x60/0xf8
[<ffff0000083fb918>] __pci_register_driver+0x40/0x48

Return EPROBE_DEFER in that case so the driver can register the device
later.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-12 09:46:46 +02:00
..
Kconfig uio-hv-generic: new userspace i/o driver for VMBus 2016-12-06 11:52:49 +01:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
uio_aec.c uio: uio_aec: remove unnecessary pci_set_drvdata() 2013-09-26 08:47:25 -07:00
uio_cif.c uio: add SPDX license tags 2018-07-21 15:41:20 +02:00
uio_dmem_genirq.c uio: fix dmem_region_start computation 2016-08-31 13:07:30 +02:00
uio_fsl_elbc_gpcm.c uio: add SPDX license tags 2018-07-21 15:41:20 +02:00
uio_hv_generic.c uio_hv_generic: drop #ifdef DEBUG 2018-09-12 09:46:46 +02:00
uio_mf624.c uio_mf624: Align memory regions to page size and set correct offsets 2017-04-08 18:13:28 +02:00
uio_netx.c uio: add SPDX license tags 2018-07-21 15:41:20 +02:00
uio_pci_generic.c uio: add SPDX license tags 2018-07-21 15:41:20 +02:00
uio_pdrv_genirq.c Revert "uio: constify of_device_id array" 2015-04-03 16:04:21 +02:00
uio_pruss.c uio: pruss: fix error handling in probe 2018-08-02 10:14:26 +02:00
uio_sercos3.c uio: add SPDX license tags 2018-07-21 15:41:20 +02:00
uio.c uio: ensure class is registered before devices 2018-09-12 09:46:46 +02:00