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    SubjectRe: [RFC PATCH 2/2] init: Allow multi-line output of kernel command line
    On Wed, 20 May 2020 13:36:45 -0700 Joe Perches <joe@perches.com> wrote:

    > On Wed, 2020-05-20 at 21:10 +0900, Sergey Senozhatsky wrote:
    > > On (20/05/19 21:58), Joe Perches wrote:
    > > [..]
    > > > > Maybe we can
    > > > > use here something rather random and much shorter instead. E.g.
    > > > > 256 chars. Hmm. How
    > > >
    > > > min(some_max like 132/256, PRINTK_LOG_LINE_MAX)
    > > >
    > > > would work.
    > >
    > > An alternative approach would be to do what we do in the
    > > print_modules() (the list of modules which can definitely
    > > be longer than 1K chars).
    > >
    > > We can split command line in a loop - memchr(pos, ' ') - and
    > > pr_cont() parts of the command line. pr_cont() has overflow
    > > control and it flushes cont buffer before it overflows, so
    > > we should not lose anything.
    >
    > It doesn't matter much here, but I believe
    > there's an 8k max buffer for pr_cont output.
    >
    > include/linux/printk.h:#define CONSOLE_EXT_LOG_MAX 8192
    >
    > Anyway, no worries, it simplifies the loop if
    > done that way.

    I'm wondering if we shold add a kernel puts() (putsk()? yuk) which can
    puts() a string of any length.

    I'm counting around 150 instances of printk("%s", ...) and pr_foo("%s",
    ...) which could perhaps be converted, thus saving an argument.

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