# Re: \[PATCH v3 2/6\] PM / Runtime: introduce pm\_runtime\_set\[get\]\_memalloc\_noio()

- From: Alan Stern \<stern@rowland.harvard.edu\>
- Date: 2012-10-31 15:20:08 
- List: netdev
- Page: https://ratatoskr.run/netdev/2012/10/3949674
- Thread: https://ratatoskr.run/netdev/2012/10/3947708/t.md

```text
On Wed, 31 Oct 2012, Ming Lei wrote:

> The below idea may help the problem which 'memalloc_noio' flag isn't set during
> usb_reset_device().
> 
> - for usb mass storage device, call pm_runtime_set_memalloc_noio(true)
>   inside usb_stor_probe2() and uas_probe(), and call
>   pm_runtime_set_memalloc_noio(false) inside uas_disconnect()
>   and usb_stor_disconnect().

Why would you want to do that?  The probe and disconnect routines
usually -- but not always -- run in the khubd thread.  Surely you don't
want to prevent khubd from using GFP_KERNEL?

And what if probe runs in khubd but disconnect runs in a different 
thread?

Alan Stern

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