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

From: Jeffrey Merkey
Date: Tue Feb 02 2016 - 17:18:45 EST


On 2/2/16, Maciej W. Rozycki <macro@xxxxxxxxxxxxxx> 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