On Tue, Mar 04, 2014 at 06:52:17PM -0800, Matthew Fleming wrote:
> On Mon, Mar 3, 2014 at 4:34 PM, Matthew Fleming <mdf356 at gmail.com> wrote:
> > In upgrading to kexec-tools 2.0.5 I first got the error "Overlapping
> > memory segments at 0xbeff000"
> >
> > Adding some debugging I found locate_hole was returning incorrect
> > values. The below is from the debug I added:
> >
> > XXXMDF: look for hole size 100000, cur range [52b3000, bffffff] size 6d4cfff
> > XXXMDF: look for hole memsz=100000, found beff000
> >
> > Hmm, if we wanted 0x100000 bytes ending at 0xbffffff, that should be
> > 0xbf00000, not 0xbef000. Continuing to the second invocation:
> >
> > XXXMDF: look for hole size 1000, cur range [52b3000, befefff] size 6c4bfff
> > XXXMDF: look for hole size 1000, cur range [bfff000, bffffff] size fff
> > XXXMDF: look for hole memsz=1000, found bffe000
> >
> > Now we die with overlapping ranges, since the 0x100000 bytes at
> > 0xbeff000 overlaps 0x1000 bytes at 0xbffe000.
> >
> > The attached patch fixes the off-by-one that causes the later overlap.
>
> Fix an off-by-one in locate_hole() that can cause it to return a range
> that was previously allocated.
>
> Signed-off-by: Matthew Fleming <mdf356 at gmail.com>
Thanks. I have applied the following:
From: Matthew Fleming <mdf356@xxxxxxxxx>
Fix an off-by-one in locate_hole()
Fix an off-by-one in locate_hole() that can cause it to return a range
that was previously allocated.
In upgrading to kexec-tools 2.0.5 I first got the error "Overlapping
memory segments at 0xbeff000"
Adding some debugging I found locate_hole was returning incorrect
values. The below is from the debug I added:
XXXMDF: look for hole size 100000, cur range [52b3000, bffffff] size 6d4cfff
XXXMDF: look for hole memsz=100000, found beff000
Hmm, if we wanted 0x100000 bytes ending at 0xbffffff, that should be
0xbf00000, not 0xbef000. Continuing to the second invocation:
XXXMDF: look for hole size 1000, cur range [52b3000, befefff] size 6c4bfff
XXXMDF: look for hole size 1000, cur range [bfff000, bffffff] size fff
XXXMDF: look for hole memsz=1000, found bffe000
Now we die with overlapping ranges, since the 0x100000 bytes at
0xbeff000 overlaps 0x1000 bytes at 0xbffe000.
Signed-off-by: Matthew Fleming <mdf356 at gmail.com>
Signed-off-by: Simon Horman <horms at verge.net.au>
---
kexec/kexec.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kexec/kexec.c b/kexec/kexec.c
index 703d524..382f86a 100644
--- a/kexec/kexec.c
+++ b/kexec/kexec.c
@@ -275,7 +275,7 @@ unsigned long locate_hole(struct kexec_info *info,
hole_base = start;
break;
} else {
- hole_base = _ALIGN_DOWN(end - hole_size,
+ hole_base = _ALIGN_DOWN(end - hole_size + 1,
hole_align);
}
}
--
1.8.5.2
