Messages in this thread | | | Date | Sat, 10 Jan 2015 11:56:55 -0800 | Subject | Re: Linux 3.19-rc3 | From | Linus Torvalds <> |
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On Sat, Jan 10, 2015 at 11:47 AM, Laszlo Ersek <lersek@redhat.com> wrote: > > I grepped the tree for "fullmm", and only tlb_gather_mmu() seems to set > it. There are several instances of that function, but each sets fullmm to: > > /* Is it from 0 to ~0? */ > tlb->fullmm = !(start | (end+1)); > > So, a nonzero fullmm seems to imply (end == ~0UL).
Yes. But note how it imples "end == ~0ul", but it does *not* imply "tlb->end" having that value.
tlb->end is initialized to zero (not obvious, but it's what the call to __tlb_reset_range() does). It's then updated by __tlb_adjust_range() as we actually flush individual pages.
Linus
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