[dm-devel] Re: 2.6.24.2: 4KSTACKS + pcdrw + dm + mount -> stack overflow: ide-cd related? dm-related?

[Andrew Morton <akpm linux-foundation org>]

On Sun, 24 Feb 2008 17:02:26 +0000 Nix <nix esperi org uk> wrote:

> On 24 Feb 2008, Peter Osterlund told this:
> 
> > Nix <nix esperi org uk> writes:
> >> But while I'd normally blame pktcdvd there's only one pktcdvd function
> >> in these tracebacks (pkt_open) and it's not got a significant stack
> >> footprint.
> >
> > Did you verify that with "make checkstack" or just by looking at the
> > source code? On my system, pkt_open() consumes 584 bytes because the
> > compiler decides to inline lots of functions that would not normally
> > be part of long call chains. The following patch fixes that problem on
> > my system.
> 
> I just looked at the source; I forgot `make checkstack' existed.
> 
> On this system:
> 
> 0xc0263e0f pkt_open [vmlinux]:                          556
> 
> which is nearly as bad.
> 
> (As an aside, I'm surprised I didn't oops when packet-writing as well:
> 
> 0xc021270d udf_process_sequence [vmlinux]:              692
> 0xc020f43d udf_add_entry [vmlinux]:                     628
> 
> owch. I guess that's called via a shorter call chain...)

udf_process_sequence() seems to be another victim of gcc inlining.

udf_add_entry() defines a couple of 256-byte local arrays.