Re: [Libunwind-devel] mincore(2) problems on Linux

[Jason Evans]

On 06/04/2010 02:12 PM, Arun Sharma wrote:
> On Thu, Jun 3, 2010 at 6:19 PM, Jason Evans<address@hidden>  wrote:
> > I have been testing recent versions of libunwind on Centos 5.2 (x86_64) [...]
>
> The "address crossing page boundary" problem is orthogonal to which
> API is used and was not a reason in itself for accepting the patch
> which switched the default to mincore on Linux.

The mincore code doesn't get the "address crossing page boundary" 
problem right anyway, so it's good that other criteria were used. ;-)

> I'd be happy to take a patch to msync() that addresses the page
> crossing problem and reconsider the choice between mincore vs msync if
> there is a good test case to show one is better than the other.

I don't particularly care whether libunwind uses msync or mincore, but 
right now most of libunwind's regression tests fail for me, and if I use 
libunwind for backtracing, I get segfaults.  The attached patch fixes 
the regression for me.  If you prefer not to fix the problem in this 
fashion, hopefully the patch will at least prove useful in 
characterizing the problem.

Thanks,
Jason

0001-Modify-mincore-2-based-validate_mem-checks.patch
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