mirror of
https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git
synced 2026-10-07 04:12:04 -04:00
| Filename | Latest commit message | Latest commit date |
|---|---|---|
7d08b4eba1
[ Upstream commit 65946690ed8d972fdb91a74ee75ac0f0f0d68321 ]
The coreboot_table driver registers a coreboot bus while probing a
"coreboot_table" device representing the coreboot table memory region.
Probing this device (i.e., registering the bus) is a dependency for the
module_init() functions of any driver for this bus (e.g.,
memconsole-coreboot.c / memconsole_driver_init()).
With synchronous probe, this dependency works OK, as the link order in
the Makefile ensures coreboot_table_driver_init() (and thus,
coreboot_table_probe()) completes before a coreboot device driver tries
to add itself to the bus.
With asynchronous probe, however, coreboot_table_probe() may race with
memconsole_driver_init(), and so we're liable to hit one of these two:
1. coreboot_driver_register() eventually hits "[...] the bus was not
initialized.", and the memconsole driver fails to register; or
2. coreboot_driver_register() gets past #1, but still races with
bus_register() and hits some other undefined/crashing behavior (e.g.,
in driver_find() [1])
We can resolve this by registering the bus in our initcall, and only
deferring "device" work (scanning the coreboot memory region and
creating sub-devices) to probe().
[1] Example failure, using 'driver_async_probe=*' kernel command line:
[ 0.114217] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
...
[ 0.114307] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.1.0-rc1 #63
[ 0.114316] Hardware name: Google Scarlet (DT)
...
[ 0.114488] Call trace:
[ 0.114494] _raw_spin_lock+0x34/0x60
[ 0.114502] kset_find_obj+0x28/0x84
[ 0.114511] driver_find+0x30/0x50
[ 0.114520] driver_register+0x64/0x10c
[ 0.114528] coreboot_driver_register+0x30/0x3c
[ 0.114540] memconsole_driver_init+0x24/0x30
[ 0.114550] do_one_initcall+0x154/0x2e0
[ 0.114560] do_initcall_level+0x134/0x160
[ 0.114571] do_initcalls+0x60/0xa0
[ 0.114579] do_basic_setup+0x28/0x34
[ 0.114588] kernel_init_freeable+0xf8/0x150
[ 0.114596] kernel_init+0x2c/0x12c
[ 0.114607] ret_from_fork+0x10/0x20
[ 0.114624] Code: 5280002b 1100054a b900092a f9800011 (885ffc01)
[ 0.114631] ---[ end trace 0000000000000000 ]---
Fixes:
|
||
| .. | ||
| arm_scmi | ||
| broadcom | ||
| efi | ||
| imx | ||
| meson | ||
| psci | ||
| tegra | ||
| xilinx | ||
| arm_scpi.c | ||
| arm_sdei.c | ||
| dmi-id.c | ||
| dmi-sysfs.c | ||
| dmi_scan.c | ||
| edd.c | ||
| iscsi_ibft.c | ||
| iscsi_ibft_find.c | ||
| Kconfig | ||
| Makefile | ||
| memmap.c | ||
| pcdp.c | ||
| pcdp.h | ||
| qcom_scm-32.c | ||
| qcom_scm-64.c | ||
| qcom_scm.c | ||
| qcom_scm.h | ||
| qemu_fw_cfg.c | ||
| raspberrypi.c | ||
| scpi_pm_domain.c | ||
| stratix10-rsu.c | ||
| stratix10-svc.c | ||
| ti_sci.c | ||
| ti_sci.h | ||
| trusted_foundations.c | ||
| turris-mox-rwtm.c | ||