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    SubjectRe: Regression due to 7ff9554 "printk: convert byte-buffer to variable-length record buffer"
    On Thu, May 10, 2012 at 10:13 PM, Stephen Warren <swarren@wwwdotorg.org> wrote:
    > On 05/10/2012 02:09 PM, Stephen Warren wrote:
    >> On 05/10/2012 02:06 PM, Kay Sievers wrote:
    >>> On Thu, May 10, 2012 at 9:54 PM, Stephen Warren <swarren@wwwdotorg.org> wrote:
    >>>> On 05/09/2012 12:31 PM, Stephen Warren wrote:
    >>>>> For me, next-20120508 prints nothing when booted, and I think also
    >>>>> hangs. To solve this, I reverted:
    >>>>>
    >>>>> 7ff9554 printk: convert byte-buffer to variable-length record buffer
    >>>>>
    >>>>> In order to build, I also had to revert:
    >>>>>
    >>>>> c4e00da driver-core: extend dev_printk() to pass structured data
    >>>>>
    >>>>> Note: I'm running on an ARM system using a serial console, with
    >>>>> earlyprintk enabled.
    >>>>
    >>>> This issue still occurs in next-20120510.
    >>>>
    >>>> I've tracked it down to the assignment of msg->ts_nsec near the end of
    >>>> log_store(). If I comment this out, everything works. The problem is the
    >>>> assignment, not the call to local_clock():
    >>>>
    >>>> fails:
    >>>>        msg->ts_nsec = local_clock();
    >>>> fails:
    >>>>        msg->ts_nsec = 0;//local_clock();
    >>>> works:
    >>>>        //msg->ts_nsec = local_clock();
    >>>
    >>> Weird.
    >>>
    >>> What happens if you change it to:
    >>>   cpu_clock(logbuf_cpu);
    >>> ?
    >>>
    >>> If it works, the timestamps look ok?
    >>
    >> I doubt that would work - after all, assigning 0 fails, but not
    >> performing the assignment at all works. But, I'll go try it...
    >
    > Calling cpu_clock() instead of local_clock() fails in the same way.

    Ok, didn't really see the assign to 0 you tried, sorry. :)

    And 'dmesg' works when you run the box with the line commented out?

    And 'cat /dev/kmsg'?

    Kay
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