linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Feng Tang <feng.tang@intel.com>
To: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@kernel.org>,
	H Peter Anvin <hpa@linux.intel.com>,
	Peter Zijlstra <peterz@infradead.org>,
	"Stuart R . Anderson" <stuart.r.anderson@intel.com>,
	alan@linux.intel.com, x86@kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] x86/earlyprintk: Add a force option for pciserial device
Date: Mon, 1 Oct 2018 22:18:10 +0800	[thread overview]
Message-ID: <20181001141810.fbo3amfqnr5243mc@shbuild888> (raw)
In-Reply-To: <20181001123916.GC7269@zn.tnic>

Hi Boris,

On Mon, Oct 01, 2018 at 02:39:16PM +0200, Borislav Petkov wrote:
> On Sun, Sep 30, 2018 at 09:16:19PM +0800, Feng Tang wrote:
> > Got your point. As the following [,baudrate] is also optional, and this
> > "force" could be the last option for pciserial. The check may be
> > 
> > 	if (!strncmp(s, "force,", 6) || !strncmp(s, "force ", 6)) {
> > 		force = 1;
> > 		s += 6;
> > 	}
> 
> You have !strncmp(s, "force,", 6) twice in there. I have no clue what
> you're trying to say.

I was trying to address your last comments:

"No, you need to force the presence of "," otherwise cmdlines like this:

earlyprintk=pciserial,0:XX.X,forcedoodoo

work too."

As I rechecked, the baud rate for pciserial is optional, so there may
be no ",baudrate" following the "force". So this 2 strncmp is to
cover conditions for with and without baudrate.

> 
> > Do you mean this? 
> > 
> > 	if (((classcode >> 16 != PCI_CLASS_COMMUNICATION_MODEM) &&
> > 	     (classcode >> 16 != PCI_CLASS_COMMUNICATION_SERIAL)) ||
> > 	   (((classcode >> 8) & 0xff) != 0x02)) /* 16550 I/F at BAR0 */ {
> > 		if (!force)
> > 			return;
> > 	}
> 
> Yes.

Ok, thanks


Thanks,
Feng

  reply	other threads:[~2018-10-01 14:12 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-09-28  9:40 [PATCH v2] x86/earlyprintk: Add a force option for pciserial device Feng Tang
2018-09-29 16:34 ` Borislav Petkov
2018-09-30 13:16   ` Feng Tang
2018-10-01 12:39     ` Borislav Petkov
2018-10-01 14:18       ` Feng Tang [this message]
2018-10-01 20:30         ` Borislav Petkov
2018-10-02  9:16           ` Feng Tang
2018-10-02  9:17             ` Thomas Gleixner
2018-10-02  9:48               ` Feng Tang
2018-10-02 10:44                 ` Thomas Gleixner
2018-10-02 12:10                   ` Feng Tang
2018-10-02 15:31                     ` Feng Tang
2018-10-02 15:41                       ` Thomas Gleixner
2018-10-02 15:49                         ` Feng Tang

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20181001141810.fbo3amfqnr5243mc@shbuild888 \
    --to=feng.tang@intel.com \
    --cc=alan@linux.intel.com \
    --cc=bp@alien8.de \
    --cc=hpa@linux.intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=peterz@infradead.org \
    --cc=stuart.r.anderson@intel.com \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).