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    SubjectRe: [PATCH v5 0/2] printk: Console owner and waiter logic cleanup
    On Wed, 10 Jan 2018 17:29:00 +0100
    Petr Mladek <pmladek@suse.com> wrote:

    > he next versions used lazy offload from console_unlock() when
    > the thread spent there too much time. IMHO, this is one
    > very promising solution. It guarantees that softlockup
    > would never happen. But it tries hard to get the messages
    > out immediately.
    >
    > Unfortunately, it is very complicated. We have troubles to understand
    > the concerns, for example see the long discussion about v3 at
    > https://lkml.kernel.org/r/20170509082859.854-1-sergey.senozhatsky@gmail.com
    > I admit that I did not have enough time to review this.
    >
    >
    > Anyway, in October, 2017, Steven came up with a completely
    > different approach (console owner/waiter transfer). It does
    > not guarantee that the softlockup will not happen. But it
    > does not suffer from the problem that blocked the obvious
    > solution for years. It moves the owner at runtime, so
    > it is guaranteed that the new owner would continue
    > printing.

    Yes, I believe my solution and the offloading solution are two agnostic
    solutions, and they are not mutually exclusive. They both can be
    applied. But mine shouldn't be controversial as it has no down sides
    from the current printk solution.

    After adding this one, if issues come up, we should have a better idea
    of how to handle them, because I'm betting the issues will only come up
    in some pretty unique scenarios. And they may even be solved without
    having to touch printk (and hurt the get out ASAP requirement). I don't
    want to paper over some real issues of those that use printk, with
    printk work arounds.

    -- Steve

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