Re: [PATCH] mm/filemap: do not allocate cache pages beyond end of file at read
From: Kirill A. Shutemov
Date: Mon Oct 28 2019 - 08:57:05 EST
On Mon, Oct 28, 2019 at 01:47:16PM +0100, Linus Torvalds wrote:
> On Mon, Oct 28, 2019 at 1:42 PM Kirill A. Shutemov <kirill@xxxxxxxxxxxxx> wrote:
> > I've tried something of this sort back in 2013:
> > http://lore.kernel.org/r/1377099441-2224-1-git-send-email-kirill.shutemov@xxxxxxxxxxxxxxx
> > and I've got push back.
> > Apparently, some filesystems may not have valid i_size before >readpage().
> > Not sure if it's still the case...
> Well, I agree that there might be some network filesystem that might
> have inode sizes that are stale, but if that's the case then I don't
> think your previous patch works either.
> It too will avoid the readpage() if the read position is beyond i_size.
Yes. That's the reason the patch was rejected back then.
My point is that we need to make sure that this patch not break anything.
Kirill A. Shutemov