Re: [PATCH v4 4/4] pr_emerg add WARN_XX() debugger options

From	Jeffrey Merkey <jeffmerkey@gmail.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v4 4/4] pr_emerg add WARN_XX() debugger options
Date	2016-02-02 23:20 +0100
Message-ID	<qXRsK-1hN-7@gated-at.bofh.it> (permalink)
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On 2/2/16, Maciej W. Rozycki <macro@linux-mips.org> wrote:
> On Mon, 1 Feb 2016, Jeffrey Merkey wrote:
>
>> If a debugger is loaded it will not crash, just enter the debugger.
>> But yes, it will int3 if set and no debugger has been loaded to handle
>> the int3 condition.  Hmmm.  Maybe its better just to skip calling
>> pr_emerg and put this logic as a single call somewhere else.
>
>  What's the point?  If you have a debugger loaded, then surely you can
> just set a breakpoint anywhere you like using whatever user interface the
> debugger provides for setting breakpoints.  You can actually set any
> number of software breakpoints you like wherever you like, depending on
> what you actually want to debug.  I fail to see why it would have to be
> prearranged within the kernel -- do you have a configuration where you run
> the kernel from ROM by any chance?
>
>   Maciej
>

No ROM here.  I resubmitted this as series 5 and dropped the change to
pr_emerg for the very reasons you stated.  I verified what you said
was correct by reviewing several code paths and its not a good place
for that.  Folks expect this function to act like a printk on
steroids, not as a terminal placement of a BUG().

Jeff

Thread

[PATCH v4 4/4] pr_emerg add WARN_XX() debugger options Jeffrey Merkey <jeffmerkey@gmail.com> - 2016-02-02 00:40 +0100
  Re: [PATCH v4 4/4] pr_emerg add WARN_XX() debugger options Jeffrey Merkey <jeffmerkey@gmail.com> - 2016-02-02 03:10 +0100
    Re: [PATCH v4 4/4] pr_emerg add WARN_XX() debugger options "Maciej W. Rozycki" <macro@linux-mips.org> - 2016-02-02 20:50 +0100
      Re: [PATCH v4 4/4] pr_emerg add WARN_XX() debugger options Jeffrey Merkey <jeffmerkey@gmail.com> - 2016-02-02 23:20 +0100
  Re: [PATCH v4 4/4] pr_emerg add WARN_XX() debugger options Steven Rostedt <rostedt@goodmis.org> - 2016-02-02 03:10 +0100

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