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    SubjectRe: [PATCH] i386 rw_semaphores fix

    > You need sterner testing stuff :) I hit the BUG at the end of rwsem_wake()
    > in about a second running rwsem-4. Removed the BUG and everything stops
    > in D state.
    > Grab rwsem-4 from
    > It's very simple. But running fully in-kernel shortens the
    > code paths enormously and allows you to find those little
    > timing windows. Run rmsem-4 in two modes: one with
    > the schedule() in sched() enabled, and also with it
    > commented out. If it passes that, it works. When
    > you remove the module it'll print out the number of
    > read-grants versus write-grants. If these run at 6:1
    > with schedule() disabled then you've kicked butt.
    > Also, rwsem-4 checks that the rwsems are actually providing
    > exclusion between readers and writers, and between
    > writers and writers. A useful thing to check, that.

    It now works (patch to follow).

    schedule() enabled:
    reads taken: 686273
    writes taken: 193414

    schedule() disabled:
    reads taken: 585619
    writes taken: 292997

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