Re: mm: swap: locking in release_pages()

[Michal Hocko]

On Tue 05-04-22 13:36:09, Alexander Sverdlin wrote:
> Hello Michal,
> 
> thanks for the quick reply!
> 
> On 05/04/2022 12:43, Michal Hocko wrote:
> >> 1. Crash of v5.4.170 on an ARM32 machine:
> >>
> >> Unable to handle kernel NULL pointer dereference at virtual address 00000104
> >> pgd = e138149d
> >> [00000104] *pgd=84d2fd003, *pmd=8ffd6f003
> >> Internal error: Oops: a07 [#1] PREEMPT SMP ARM
> >> ...
> >> CPU: 1 PID: 6172 Comm: AaSysInfoRColle Tainted: G    B      O      5.4.170-... #1
> >> Hardware name: Keystone
> >> PC is at release_pages+0x194/0x358
> >> LR is at release_pages+0x10c/0x358
> > Which LOC does this correspond to? (faddr2line should give you a nice
> > output).
> 
> Sorry, I forgot this info in the initial report:
> 
> this is indeed the del_page_from_lru_list() in this crash.

Could you be more specific please? Is the problem in list_del or
update_lru_size?

-- 
Michal Hocko
SUSE Labs