From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Tom Rini <trini@kernel.crashing.org>
Cc: linuxppc-dev@ozlabs.org
Subject: Re: bug in arch/ppc/boot/common/util.S: cmplwi cr0,r3,r4 ?
Date: Tue, 09 Aug 2005 10:33:12 +0200 [thread overview]
Message-ID: <1123576393.30257.155.camel@gaston> (raw)
In-Reply-To: <20050809005050.GF3187@smtp.west.cox.net>
On Mon, 2005-08-08 at 17:50 -0700, Tom Rini wrote:
> On Thu, Aug 04, 2005 at 11:44:08AM +0200, Benjamin Herrenschmidt wrote:
> > On Wed, 2005-08-03 at 15:18 +0200, Frank van Maarseveen wrote:
> > > I think "cmplwi" expects an immediate vale as last operand
> > > around line 255 of arch/ppc/boot/common/util.S:
> > >
> > > addi r4,r4,_etext@l # r8 = &_etext
> > > 1: dcbf r0,r3 # Flush the data cache
> > > icbi r0,r3 # Invalidate the instruction cache
> > > addi r3,r3,0x10 # Increment by one cache line
> > > cmplwi cr0,r3,r4 # Are we at the end yet?
> > > ^^
> > > blt 1b # No, keep flushing and invalidating
> > >
> > > I guess it should have been:
> > >
> > > cmplw cr0,r3,r4 # Are we at the end yet?
> >
> > Yup, looks like a real bug to me, Tom ?
>
> Sounds correct to me. I wonder why the assembler hasn't barfed, or is
> is translating the ascii values of r4. I'll pass this along once 2.6.14
> opens just because the code has been that way for so many years, I don't
> think it's a critical bug.
>
Because our assembler has no clue what r4 is :) Look at our ppc_asm.h
and you'll understand :)
Ben.
prev parent reply other threads:[~2005-08-09 8:38 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-08-03 13:18 bug in arch/ppc/boot/common/util.S: cmplwi cr0,r3,r4 ? Frank van Maarseveen
2005-08-04 9:44 ` Benjamin Herrenschmidt
2005-08-09 0:50 ` Tom Rini
2005-08-09 2:20 ` Hollis Blanchard
2005-08-09 8:33 ` Benjamin Herrenschmidt [this message]
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=1123576393.30257.155.camel@gaston \
--to=benh@kernel.crashing.org \
--cc=linuxppc-dev@ozlabs.org \
--cc=trini@kernel.crashing.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).