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    SubjectRe: [PATCH 25/30] panic, printk: Add console flush parameter and convert panic_print to a notifier
    On Wed 2022-04-27 19:49:19, Guilherme G. Piccoli wrote:
    > Currently the parameter "panic_print" relies in a function called
    > directly on panic path; one of the flags the users can set for
    > panic_print triggers a console replay mechanism, to show the
    > entire kernel log buffer (from the beginning) in a panic event.
    >
    > Two problems with that: the dual nature of the panic_print
    > isn't really appropriate, the function was originally meant
    > to allow users dumping system information on panic events,
    > and was "overridden" to also force a console flush of the full
    > kernel log buffer. It also turns the code a bit more complex
    > and duplicate than it needs to be.
    >
    > This patch proposes 2 changes: first, we decouple panic_print
    > from the console flushing mechanism, in the form of a new kernel
    > core parameter (panic_console_replay); we kept the functionality
    > on panic_print to avoid userspace breakage, although we comment
    > in both code and documentation that this panic_print usage is
    > deprecated.
    >
    > We converted panic_print function to a panic notifier too, adding
    > it on the panic informational notifier list, executed as the final
    > callback. This allows a more clear code and makes sense, as
    > panic_print_sys_info() is really a panic-time only function.
    > We also moved its code to kernel/printk.c, it seems to make more
    > sense given it's related to printing stuff.

    I really like both changes. Just please split it them into two
    patchset. I mean one patch for the new "panic_console_replay"
    parameter and 2nd that moves "printk_info" into the notifier.

    Best Regards,
    Petr

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