I am using kernel version 4.14.65 (on Android pie [ARM]).
No additional patches applied on top of vanilla.(Core MM).
If I change in the vmscan.c as below patch, it will work.
Regards,
Pankaj
From: Michal Hocko <mho...@kernel.org>
Sent: 14 March 2019 14:11:20
To: Pankaj Suryawanshi
Cc: linux-kernel@vger.kernel.org; minc...@kernel.org
Subject: [External] Re: vmscan: Reclaim unevictable pages
CAUTION: This email originated from outside of the organization. Do not click
links or open attachments unless you recognize the sender and know the content
is safe.
On Thu 14-03-19 08:23:10, Pankaj Suryawanshi wrote:
>
> Below is the Error Msg :
>
> [ 24.718792] page dumped because: VM_BUG_ON_PAGE(PageLRU(page) ||
> PageUnevictable(page))
> [ 24.726949] page->mem_cgroup:bd008c00
> [ 24.730693] ------------[ cut here ]------------
> [ 24.735304] kernel BUG at mm/vmscan.c:1350!
> [ 24.739478] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
Just curious. Which kernel version is that? Are there any addional
patches applied on top of vanilla?
> Solved the issue by below patch.
>
>
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index be56e2e..2e51edc 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -990,15 +990,17 @@ static unsigned long shrink_page_list(struct list_head
> *page_list,
> page = lru_to_page(page_list);
> list_del(&page->lru);
>
> if (!trylock_page(page)) {
> goto keep;
> }
>
> VM_BUG_ON_PAGE(PageActive(page), page);
>
> sc->nr_scanned++;
>
> if (unlikely(!page_evictable(page)))
> - goto activate_locked;
> + goto cull_mlocked;
>
> if (!sc->may_unmap && page_mapped(page))
> goto keep_locked;
> @@ -1331,6 +1333,12 @@ static unsigned long shrink_page_list(struct list_head
> *page_list,
> } else
> list_add(&page->lru, &free_pages);
> continue;
> +cull_mlocked:
> + if (PageSwapCache(page))
> + try_to_free_swap(page);
> + unlock_page(page);
> + list_add(&page->lru, &ret_pages);
> + continue;
>
> activate_locked:
> /* Not a candidate for swapping, so reclaim swap space. */
>
>
>
>
> From: Pankaj Suryawanshi
> Sent: 14 March 2019 13:23:53
> To: linux-kernel@vger.kernel.org
> Cc: minc...@kernel.org
> Subject: vmscan: Reclaim unevictable pages
>
>
>
> Hello ,
>
> shrink_page_list() returns , number of pages reclaimed, when pages is
> unevictable it returns VM_BUG_ON_PAGE(PageLRU(page) ||
> PageUnevicatble(page),page);
>
> We can add the unevictable pages in reclaim list in shrink_page_list(),
> return total number of reclaim pages including unevictable pages, let the
> caller handle unevictable pages.
>
> Regards,
> Pankaj
>
> *************************************************************************************************************************************************************
> eInfochips Business Disclaimer: This e-mail message and all attachments
> transmitted with it are intended solely for the use of the addressee and may
> contain legally privileged and confidential information. If the reader of
> this message is not the intended recipient, or an employee or agent
> responsible for delivering this message to the intended recipient, you are
> hereby notified that any dissemination, distribution, copying, or other use
> of this message or its attachments is strictly prohibited. If you have
> received this message in error, please notify the sender immediately by
> replying to this message and please delete it from your computer. Any views
> expressed in this message are those of the individual sender unless otherwise
> stated. Company has taken enough precautions to prevent the spread of
> viruses. However the company accepts no liability for any damage caused by
> any virus transmitted by this email.
> *************************************************************************************************************************************************************
--
Michal Hocko
SUSE Labs
