Messages in this thread | | | Date | Sun, 24 May 2020 10:42:30 +0300 | From | Mike Rapoport <> | Subject | Re: [PATCH 0/7] Record the mm_struct in the page table pages |
| |
On Tue, Apr 28, 2020 at 06:51:26PM -0700, Matthew Wilcox wrote: > On Wed, Apr 29, 2020 at 03:26:24AM +0300, Kirill A. Shutemov wrote: > > On Tue, Apr 28, 2020 at 12:44:42PM -0700, Matthew Wilcox wrote: > > > From: "Matthew Wilcox (Oracle)" <willy@infradead.org> > > > > > > Pages which are in use as page tables have some space unused in struct > > > page. It would be handy to have a pointer to the struct mm_struct that > > > they belong to so that we can handle uncorrectable errors in page tables > > > more gracefully. There are a few other things we could use it for too, > > > such as checking that the page table entry actually belongs to the task > > > we think it ought to. This patch series does none of that, but does > > > lay the groundwork for it. > > > > > > Matthew Wilcox (Oracle) (7): > > > > How does it work for kernel side of virtual address space? > > init_mm
A note to keep in mind is that most of the kernel page tables are seen as PG_reserved rather than PageTable().
> > And your employer may be interested in semantics around > > CONFIG_ARCH_WANT_HUGE_PMD_SHARE :P > > I was thinking about that. Right now, it's only useful for debugging > purposes (as you point out in a later email). I think it's OK if shared > PMDs aren't supported as well as regular PTEs, just because there are > so few of them that uncorrectable errors are less likely to strike in > those pages. >
-- Sincerely yours, Mike.
| |