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    SubjectRe: [RFC][PATCH 4/6] arm, mm: Convert arm to generic tlb
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    On Thu, 2012-05-17 at 10:51 +0100, Russell King wrote:
    > On Thu, May 17, 2012 at 10:30:23AM +0100, Catalin Marinas wrote:
    > > Another minor thing is that on newer ARM processors (Cortex-A15) we
    > > need the TLB shootdown even on UP systems, so tlb_fast_mode should
    > > always return 0. Something like below (untested):
    >
    > No Catalin, we need this for virtually all ARMv7 CPUs whether they're UP
    > or SMP, not just for A15, because of the speculative prefetch which can
    > re-load TLB entries from the page tables at _any_ time.

    Hmm,. so this is mostly because of the confusion/coupling between
    tlb_remove_page() and tlb_remove_table() I guess. Since I don't see the
    freeing of the actual pages being a problem with speculative TLB
    reloads, just the page-tables.

    Should we introduce a tlb_remove_table() regardless of
    HAVE_RCU_TABLE_FREE which always queues the tables regardless of
    tlb_fast_mode()?




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