In the kerneloops.org stats, a new oops is rapidly climbing the charts.

The oops is a page fault in the ext3 "do_slit" function, and the first

report of it was with 2.6.26-rc6-git3.
It happens with various applications; the backtraces are at:
http://www.kerneloops.org/search.php?search=do_split
but are generally of this pattern:
*do_split

ext3_add_entry

ext3_rename

vfs_rename

... <various paths into vfs_rename> ...
or
*do_split

? add_dirent_to_buf

ext3_add_entry

ext3_new_inode

ext3_add_nondir

ext3_create

vfs_create

....
did we change anything in ext
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Arjan, I was just looking at kerneloops last night, seeing the count for

this oops climb, and was wishing there were some way to annotate an oops

signature with more info.  If I could have tagged this with the RH

bugzilla nr. it might have saved a lot of time for folks.  Is this

feasible?  Or is finding the oops text in bugzilla the only way?
Thanks,
-Eric
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there's a way to add a description to oopses (you might have seen some of these

descriptions already); however I've not implemented an account system yet so for

now it's only me who can add these.

--

Ok, that was my guess.  I'll shoot you an email next time.  :)
Thanks,

-Eric

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This is a bug in rawhide in gcc miscompiling something...
https://bugzilla.redhat.com/show_bug.cgi?id=451068
Dave.

--

If I understand it correctly that's a bug in upstream gcc 4.3.1

(but not in gcc 4.3.0)?
Expect a lot more of this to pop up in the future.
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
--

it/s better to find if the gcc guys made a testcase for this bug (they normally do) and

test based on that.

--

The gcc Bugzilla contains a testcase.
But how do you plan to integrate it into a kernel build?
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
--

we already have several of these.

Just look at scripts/gcc-x86_64-has-stack-protector.sh for an example of such a beast.

--

Checking whether gcc supports some flags is easy.
But miscompilations are a different issue.
Especially since we also want to reject broken gcc versions for cross

compilations.
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
--

have you actually looked at this script?

You didn't, since the script doesn't check if gcc supports some flag.

It checks very specifically for a code generation pattern...
Please go look at the script first before responding.
--

I did look, but I missed the last pipe...
Do we know for sure this bug can only trigger on 32bit x86?
Or is there anything else I miss in gcc-x86_64-has-stack-protector.sh

that allows to use this approach to check for wrong code generation

caused by platform independent gcc bugs?
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
--

Adrian Bunk writes:

 > On Thu, Jun 19, 2008 at 03:42:34PM +1000, Dave Airlie wrote:

 > > On Thu, Jun 19, 2008 at 3:36 PM, Arjan van de Ven <arjan@linux.intel.com> wrote:

 > > > In the kerneloops.org stats, a new oops is rapidly climbing the charts.

 > > > The oops is a page fault in the ext3 "do_slit" function, and the first

 > > > report of it was with 2.6.26-rc6-git3.

 > > >

 > > > It happens with various applications; the backtraces are at:

 > > >

 > > > http://www.kerneloops.org/search.php?search=do_split

 > >

 > > This is a bug in rawhide in gcc miscompiling something...

 > >

 > > https://bugzilla.redhat.com/show_bug.cgi?id=451068

 >

 > If I understand it correctly that's a bug in upstream gcc 4.3.1

 > (but not in gcc 4.3.0)?

 >

 > Expect a lot more of this to pop up in the future.

 > Should we #error for gcc 4.3.1?
There are other nasty bugs in gcc-4.3.0. I actually

had to completely ban 4.3.0 in a user-space project

I'm involved with (Erlang) due to gcc PR36339 (fixed

in 4.3.1).
What's the gcc bugzilla number for this new 4.3.1 bug?

--

#36533
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
--

Gaah. I should read all my email instead of wasting my time trying to

match up the code with what I can reproduce..
		Linus

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unfortunately, kerneloops.org didn't pick up the link to this bug (due to the fact

that the oops in the bug was a jpeg....)... maybe one day if I'm really bored

I'll implement OCR into it ;)
sorry about wasting your time
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thanks for letting us know so fast!

I've marked this one in the database as a fedora gcc bug

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