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    SubjectRe: [PATCH printk v5 1/1] printk: extend console_lock for per-console locking
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    Hi,

    On 06/05/2022 08:43, Marek Szyprowski wrote:
    > Hi John,
    >
    > On 06.05.2022 00:33, John Ogness wrote:
    >> On 2022-05-05, John Ogness <john.ogness@linutronix.de> wrote:
    >>> I will go through and check if all access to AML_UART_CONTROL is
    >>> protected by port->lock.
    >> The startup() callback of the uart_ops is not called with the port
    >> locked. I'm having difficulties identifying if the startup() callback
    >> can occur after the console was already registered via meson_uart_init()
    >> and could be actively printing, but I see other serial drivers are
    >> protecting their registers in the startup() callback with the
    >> port->lock.
    >>
    >> Could you try booting the meson hardware with the following change? (And
    >> removing any previous debug changes I posted?)
    >
    > Bingo! It looks that the startup() is called when getty initializes
    > console. This fixed the issues observed on the Amlogic Meson based boards.
    >
    > Feel free to add:
    >
    > Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
    >
    > Best regards

    Thanks all for figuring out the issue, perhaps other uart drivers could fall
    in the same issue if startup code isn't protected with lock ?

    Neil

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