linux-kernel - Re: [PATCH 01/11] ftrace: handle generic arch calls

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]

Message-ID: <20081029201646.GA1816@cs181140183.pp.htv.fi>
Date:	Wed, 29 Oct 2008 22:16:46 +0200
From:	Adrian Bunk <bunk@...nel.org>
To:	Sam Ravnborg <sam@...nborg.org>
Cc:	Steven Rostedt <rostedt@...dmis.org>,
	LKML <linux-kernel@...r.kernel.org>, Ingo Molnar <mingo@...e.hu>,
	Frederic Weisbecker <fweisbec@...il.com>,
	Abhishek Sagar <sagar.abhishek@...il.com>,
	"David S. Miller" <davem@...emloft.net>,
	Thomas Gleixner <tglx@...utronix.de>,
	Peter Zijlstra <peterz@...radead.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Steven Rostedt <srostedt@...hat.com>
Subject: Re: [PATCH 01/11] ftrace: handle generic arch calls

On Wed, Oct 29, 2008 at 08:49:56PM +0100, Sam Ravnborg wrote:
> On Wed, Oct 29, 2008 at 03:24:19PM -0400, Steven Rostedt wrote:
> > 
> > On Wed, 29 Oct 2008, Sam Ravnborg wrote:
> > > >  
> > > > +if ($arch eq "x86") {
> > > > +    if ($bits == 64) {
> > > > +	$arch = "x86_64";
> > > > +    } else {
> > > > +	$arch = "i386";
> > > > +    }
> > > > +}
> > > > +
> > > >  if ($arch eq "x86_64") {
> > > >      $section_regex = "Disassembly of section";
> > > >      $function_regex = "^([0-9a-fA-F]+)\\s+<(.*?)>:";
> > > > 
> > > 
> > > This looks strange to my eyes.
> > > Why not do the more obvious:
> > > if ($arch eq "x86" && $bits == 64) {
> > > 
> > > The change above is like trying to stick to the old i386/x86_64
> > > notation.
> > 
> > Trying to fix it tells me my answer to why I did it his way ;-)
> > 
> > I have queued patches that will support other archs so x86 is not the
> > only arch that can be used here. But x86 is special, it seems to be the 
> > only arch (that I know of, correct me if I'm wrong) that can compile with
> > multiple archs defined: make ARCH=x86_64, make ARCH=i386, or
> > make ARCH=x86. All are legit.
> > 
> > Now how do we handle this. I've been fine for all my testing to do just 
> > x86_64 and i386 because a normal make of x86 will use automatically set
> > ARCH to i386 or x86_64 depending on the build.
> > 
> > But then Adrian Bunk pointed out that "make ARCH=x86" fails. Now I need to 
> > add a case for x86, but still allow for x86_64 or i386 being passed in.
> > 
> > Since x86 is the ambiguous case, I made it the one that would be converted 
> > to i386 or x86_64 since those could be passed in directly.
> The trick is usually to replace use of ARCH with SRCARCH.

That won't help - what he wants to know is whether he's on 32bit or
on 64bit.

> 	Sam

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/