On Tue, Sep 11, 2007 at 04:05:09PM -0500, Eric Sandeen wrote: > Dave Jones wrote: > > On Tue, Sep 11, 2007 at 03:05:52PM -0500, Eric Sandeen wrote: > > > > > In light of this, I'd like to propose that we turn off > > > DEBUG_STACKOVERFLOW in Fedora, at least on x86/4KSTACKS. I think it > > > does more harm than good; the warning is going to turn deadly most of > > > the time. > > > > > > I also had sent a patch to LKML to print whether or not the stack was > > > overflowing, or had ever overflowed, on a kernel panic. It's not yet > > > been merged. > > > > > > ... any comments? I can file a bug but thought some discussion might be > > > in order. > > > > We could turn it off everywhere expect the -debug kernels and > > just have XFS + -debug be a 'dont do that' thing. > > Well, I didn't actually *say* xfs ... *cough* ;-) > > There have been reports of mount.nfs, for example, using within 600 > bytes of the end of the stack... if they'd caught an interrupt at the > end of whatever callchain that was, they'de be uncomfortably close to > the edge too. > > And - what is the use of keeping the warning turned on *anywhere* when > really, all it does is turn a near-miss into the real thing? If you > actually overrun the stack, you're probably going to oops anyway, and > get about the same backtrace - except, hopefully less often, w/o the > warning going off. > > I see this almost entirely as statistically shaving another ~500 bytes > off the usable stack, without generating much useful information in return. > > Or am I missing some other usefulness of this? Hmm, good point. Dave -- http://www.codemonkey.org.uk _______________________________________________ Fedora-kernel-list mailing list Fedora-kernel-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/fedora-kernel-list
