Re: vmalloc with GFP_NOFS

From: Michal Hocko
Date: Thu May 10 2018 - 01:58:47 EST


On Wed 09-05-18 15:02:31, Darrick J. Wong wrote:
> On Wed, May 09, 2018 at 11:04:47PM +0200, Michal Hocko wrote:
> > On Wed 09-05-18 08:13:51, Darrick J. Wong wrote:
[...]
> > > > FS resp. IO submitting code paths have to be careful when allocating
> > >
> > > Not sure what 'FS resp. IO' means here -- 'FS and IO' ?
> > >
> > > (Or is this one of those things where this looks like plain English text
> > > but in reality it's some sort of markup that I'm not so familiar with?)
> > >
> > > Confused because I've seen 'resp.' used as shorthand for
> > > 'responsible'...
> >
> > Well, I've tried to cover both. Filesystem and IO code paths which
> > allocate while in sensitive context. IO submission is kinda clear but I
> > am not sure what a general term for filsystem code paths would be. I
> > would be greatful for any hints here.
>
> "Code paths in the filesystem and IO stacks must be careful when
> allocating memory to prevent recursion deadlocks caused by direct memory
> reclaim calling back into the FS or IO paths and blocking on already
> held resources (e.g. locks)." ?

Great, thanks!
--
Michal Hocko
SUSE Labs