Re: [PATCH] ubifs: Fix a sleep-in-atomic bug in ubifs_read_nnode

From: Richard Weinberger
Date: Mon Jun 05 2017 - 04:25:50 EST


Jia-Ju Bai,

Am 05.06.2017 um 05:38 schrieb Jia-Ju Bai:
> The driver may sleep under a spin lock, and the function call path is:
> ubifs_change_lp (acquire the lock by spin_lock)
> change_category
> ubifs_remove_from_cat
> remove_from_lpt_heap
> dbg_check_heap
> ubifs_lpt_lookup
> ubifs_read_nnode
> kzalloc(GFP_NOFS) --> may sleep
>
> To fix it, "GFP_NOFS" is replaced with "GFP_ATOMIC".

So, this happens only when dbg_check_heap() is activated, right?

Thanks,
//richard