Re: [RFC PATCH 1/2] mm, vmscan: account the number of isolated pagesper zone

From: Michal Hocko
Date: Wed Jan 25 2017 - 07:35:01 EST

On Wed 25-01-17 19:33:59, Tetsuo Handa wrote:
> Michal Hocko wrote:
> > I think we are missing a check for fatal_signal_pending in
> > iomap_file_buffered_write. This means that an oom victim can consume the
> > full memory reserves. What do you think about the following? I haven't
> > tested this but it mimics generic_perform_write so I guess it should
> > work.
> Looks OK to me. I worried
> #define AOP_FLAG_UNINTERRUPTIBLE 0x0001 /* will not do a short write */
> which forbids (!?) aborting the loop. But it seems that this flag is
> no longer checked (i.e. set but not used). So, everybody should be ready
> for short write, although I don't know whether exofs / hfs / hfsplus are
> doing appropriate error handling.

Those were using generic implementation before and that handles this
case AFAICS.

Michal Hocko