Re: [PATCH 2/2] virtio_balloon: fix race between migration and ballooning

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Jan 04, 2016 at 09:27:47AM +0900, Minchan Kim wrote:
> > I think this will cause deadlocks.
> > 
> > pages_lock now nests within page lock, balloon_page_putback
> > nests them in the reverse order.
> 
> In balloon_page_dequeu, we used trylock so I don't think it's
> deadlock.

I went over this again and I don't see the issue anymore.
I think I was mistaken, so I dropped my patch and picked
up yours. Sorry about the noise.


> > 
> > Also, there's another issue there I think: after isolation page could
> > also get freed before we try to lock it.
> 
> If a page was isolated, the page shouldn't stay b_dev_info->pages
> list so balloon_page_dequeue cannot see the page.
> Am I missing something?

I mean without locks, as it is now. With either your or my patch in
place, it's fine.

-- 
MST

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>



[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux]     [Linux OMAP]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]