Re: [PATCH] RFC: Introduce FW_INFO* functions

[Prarit Bhargava <prarit@redhat.com>]

On 09/27/2013 11:40 AM, Joe Perches wrote:
> On Fri, 2013-09-27 at 09:22 -0400, Prarit Bhargava wrote:
>> I'm proposing with this patch to do something similar to the WARN()
>> mechanism that is currently implemented in the kernel.  This
>> patchset introduces FW_INFO() and FW_INFO_DEV() which logs output
> 
> My first thought was "how ugly".
> There must be a better way than scraping dmesg output.

I am in no way married to this patch.  If anyone has a better idea I'd like to
hear it.  The dmesg log is the place that sysadmins are used to looking for it
-- it is the kernel that discovers and reports these issues.  AFAICT we've
always reported FW problems in the kernel log.

> 
>> diff --git a/kernel/panic.c b/kernel/panic.c
> []
>> @@ -445,6 +446,29 @@ void warn_slowpath_fmt_taint(const char *file, int line,
>>  }
>>  EXPORT_SYMBOL(warn_slowpath_fmt_taint);
>>  
>> +void warn_slowpath_fmt_dev(const char *file, int line,
>> +			   struct device *dev, const char *fmt, ...)
>> +{
>> +	struct slowpath_args args;
>> +
>> +	pr_info("[Firmware Info]: ");
>> +	if (dev)
>> +		pr_cont("%s %s: ",
>> +			dev_driver_string(dev), dev_name(dev));
>> +	pr_cont("at %s:%d ", file, line);
>> +
>> +	args.fmt = fmt;
>> +	va_start(args.args, fmt);
>> +	vprintk(args.fmt, args.args);
>> +	va_end(args.args);
>> +	if (dump_hardware_arch_desc())
>> +		pr_info("[Firmware Info]: %s\n", dump_hardware_arch_desc());
>> +	else
>> +		pr_info("[Firmware Info]: Hardware Unidentified\n");
>> +}
>> +EXPORT_SYMBOL(warn_slowpath_fmt_dev);
> 
> This bit should just use %pV and a single printk to
> avoid any possible message interleaving.
> 

Ah ... of course.  I'll definitely do that in a future patch.

Thanks for looking at this Joe.

P.