[openib-general] Re: RFC on SDP checkin

[Michael S. Tsirkin]

Quoting r. Libor Michalek <libor at topspin.com>:
> Subject: Re: RFC on SDP checkin
> 
> On Thu, Feb 17, 2005 at 04:03:59PM +0200, Michael S. Tsirkin wrote:
> > Quoting r. Libor Michalek <libor at topspin.com>:
> > > Possible Issues
> > >   
> > > [...] 
> > > 
> > >   - Memory locking for AIO requires a call to do_mlock() which is not a
> > >     kernel exported function, the method for calling the function is not
> > >     standard.
> > 
> > Libor, in my eyes this is the biggest issue with this gen2 sdp code.
> > In short, I dont think using do_mlock is a good idea.
> 
>   I do agree that this is one of the more, if not most, problematic area
> of the code, and I like your alternative suggestion below.

BTW, just noted that sdp_iocb.c gets current->mm directly, and keeps
this pointer cashed instead of calling get_task_mm each time.
Thus it seems a race condition may occur if the task
is exiting while the cashed value is used.

I am not fixing it since we agreed we are changing this to get_user_pages
anyway.


-- 
MST - Michael S. Tsirkin