Re: iwl3945: order 5 allocation during ifconfig up; vm problem?

From: Marc MERLIN
Date: Wed Sep 12 2012 - 01:57:43 EST


On Wed, Sep 12, 2012 at 07:16:28AM +0200, Eric Dumazet wrote:
> On Tue, 2012-09-11 at 16:25 -0700, Andrew Morton wrote:
>
> > Asking for a 256k allocation is pretty crazy - this is an operating
> > system kernel, not a userspace application.
> >
> > I'm wondering if this is due to a recent change, but I'm having trouble
> > working out where the allocation call site is.
> > --
>
> (Adding Marc Merlin to CC, since he reported same problem)
>
> Thats the firmware loading in iwlwifi driver. Not sure if it can use SG.
>
> drivers/net/wireless/iwlwifi/iwl-drv.c
>
> iwl_alloc_ucode() -> iwl_alloc_fw_desc() -> dma_alloc_coherent()
>
> It seems some sections of /lib/firmware/iwlwifi*.ucode files are above
> 128 Kbytes, so dma_alloc_coherent() try order-5 allocations

Thanks for looping me in, yes, this looks very familiar to me :)

In the other thread, Johannes Berg gave me this patch which is supposed to
help: http://p.sipsolutions.net/11ea33b376a5bac5.txt

Unfortunately due to very long work days, I haven't had the time to try it
out yet, but I will soon.

Would that help in this case too?

And to answer David Rientjes, I also have compaction on:
gandalfthegreat:~# zgrep CONFIG_COMPACTION /proc/config.gz
CONFIG_COMPACTION=y

Full config:
http://marc.merlins.org/tmp/config-3.5.2-amd64-preempt-noide-20120731

If that helps for comparison, my thread is here:
http://www.spinics.net/lists/linux-wireless/msg96438.html

Thanks,
Marc
--
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems ....
.... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/
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