power: supply: bq25890: Fix race causing oops at boot
Before this commit the driver was registering its interrupt handler before
it registered the power_supply, causing bq->charger to potentially be NULL
when the interrupt handler runs, triggering a NULL pointer exception in
the interrupt handler:
[ 21.213531] BUG: kernel NULL pointer dereference, address: 0000000000000680
...
[ 21.213573] Hardware name: Xiaomi Inc Mipad2/Mipad, BIOS MIPad-P4.X64.0043.R03.1603071414 03/07/2016
[ 21.213576] RIP: 0010:__lock_acquire+0x5c5/0x1de0
...
[ 21.213629] Call Trace:
[ 21.213636] ? disable_irq_nosync+0x10/0x10
[ 21.213644] ? __mutex_unlock_slowpath+0x35/0x260
[ 21.213655] lock_acquire+0xb5/0x2b0
[ 21.213661] ? power_supply_changed+0x23/0x90
[ 21.213670] ? disable_irq_nosync+0x10/0x10
[ 21.213676] _raw_spin_lock_irqsave+0x48/0x60
[ 21.213682] ? power_supply_changed+0x23/0x90
[ 21.213687] power_supply_changed+0x23/0x90
[ 21.213697] __bq25890_handle_irq+0x5e/0xe0 [bq25890_charger]
[ 21.213709] bq25890_irq_handler_thread+0x26/0x40 [bq25890_charger]
[ 21.213718] irq_thread_fn+0x20/0x60
...
Fix this by moving the power_supply_register() call to above the
request_threaded_irq() call.
Note this fix includes making the following 2 (necessary) changes:
1. Switch to the devm version of power_supply_register() to avoid the
need to make the error-handling in probe() more complicated.
2. Rename the "irq_fail" label to "err_unregister_usb_notifier" since
the old name no longer makes sense after this fix.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
1 file changed