linux-kernel - Re: [PATCH v8 2/5] usb: early: add driver for xhci debug capability

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 1 Jun 2017 11:35:35 +0800
From:   Lu Baolu <baolu.lu@...ux.intel.com>
To:     Steven Rostedt <rostedt@...dmis.org>
Cc:     Vlastimil Babka <vbabka.lkml@...il.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Ingo Molnar <mingo@...hat.com>,
        Mathias Nyman <mathias.nyman@...ux.intel.com>,
        tglx@...utronix.de, peterz@...radead.org,
        linux-usb@...r.kernel.org, x86@...nel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH v8 2/5] usb: early: add driver for xhci debug capability

Hi,

On 05/31/2017 02:24 PM, Steven Rostedt wrote:
> On Wed, 31 May 2017 11:27:19 +0800
> Lu Baolu <baolu.lu@...ux.intel.com> wrote:
>
>   
>>>> +
>>>> +#define XDBC_TRACE
>>>> +#ifdef XDBC_TRACE
>>>> +#define	xdbc_trace	trace_printk  
>>> Did you forget to remove the #define XDBC_TRACE?
>>>
>>> Enabling this driver brings the "trace_printk() being used.
>>> Allocating extra memory. This means that this is a DEBUG kernel and
>>> it is unsafe for production use." message in 4.12-rcX dmesg.  
>> This feature is only for a DEBUG kernel, should not be enabled for
>> any production kernel. This was the reason I enabled trace_printk()
>> by default.
> Yes, it is perfectly fine to use trace_printk() for debug only configs.
> But if if you have it there and it is helpful to debug something that
> happens in a production system, you may want to look into creating a
> real tracepoint for the locations.

Yes. Good suggestion. I will try this.

Thank you!

Best regards,
Lu Baolu

>
> -- Steve
> --
> To unsubscribe from this list: send the line "unsubscribe linux-usb" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>