On Tue, 3 Jun 2025 10:54:49 -0700 Linus Torvalds <torva...@linux-foundation.org> wrote:
> On Tue, 3 Jun 2025 at 10:26, Steven Rostedt <rost...@goodmis.org> wrote: > > > > config DRM_TTM > > tristate > > - depends on DRM && MMU > > + depends on DRM && MMU && SHMEM > > Yeah, except I think you should just make it be > > depends on DRM && SHMEM > > because SHMEM already depends on MMU. Yeah, if I had made this a real patch I would have done that, but this was only for seeing it it would work. > > That said, our docs already say that if you disable SHMEM, it gets > replaced by RAMFS, so maybe just having a ramfs version is the > RightThing(tm). > > I don't think such a ramfs version should just return 0 - much less an > error. I think it should always redirty the page. > > IOW, I think the "ramfs" version should look something like > > folio_mark_dirty(folio); > if (wbc->for_reclaim) > return AOP_WRITEPAGE_ACTIVATE; /* Return with folio locked */ > folio_unlock(folio); > return 0; > > which is what shmem does for the "page is locked" case. I'll let someone that understand the code a bit more than I do to make such a change. My patch was just a "this makes my system build" thing and let those that know this code do the RightThing(tm). -- Steve
