Re: [PATCH 2/7] mmc: Don't use PF_MEMALLOC

From: Minchan Kim
Date: Tue Nov 17 2009 - 05:32:42 EST


On Tue, Nov 17, 2009 at 7:29 PM, Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> wrote:
> On Tue, 17 Nov 2009 16:17:50 +0900 (JST)
> KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> wrote:
>
>> Non MM subsystem must not use PF_MEMALLOC. Memory reclaim need few
>> memory, anyone must not prevent it. Otherwise the system cause
>> mysterious hang-up and/or OOM Killer invokation.
>
> So now what happens if we are paging and all our memory is tied up for
> writeback to a device or CIFS etc which can no longer allocate the memory
> to complete the write out so the MM can reclaim ?
>
> Am I missing something or is this patch set not addressing the case where
> the writeback thread needs to inherit PF_MEMALLOC somehow (at least for
> the I/O in question and those blocking it)
>

I agree.
At least, drivers for writeout is proper for using PF_MEMALLOC, I think.


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



--
Kind regards,
Minchan Kim
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/