From: Simon Horman <horms@verge.net.au>
To: Matthew Fleming <mdf356@gmail.com>
Cc: kexec@lists.infradead.org
Subject: Re: PATCH: bug in locate_hole()
Date: Tue, 4 Mar 2014 13:03:31 +0900 [thread overview]
Message-ID: <20140304040331.GG18200@verge.net.au> (raw)
In-Reply-To: <CAMBSHm_fvPTjdEwgVdyMGPi=3et+JEP-G5TNV986yXWYw35YYw@mail.gmail.com>
Thanks Matthew.
Could you provide a signed-off-by line?
On Mon, Mar 03, 2014 at 04:34:35PM -0800, Matthew Fleming 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.
>
> Thanks,
> matthew
> --- kexec.c.orig 2014-03-03 16:08:53.289844106 -0800
> +++ kexec.c 2014-03-03 16:09:04.960844107 -0800
> @@ -272,17 +272,17 @@ unsigned long locate_hole(struct kexec_i
> }
> /* Is there enough space left so we can use it? */
> size = end - start;
> if (!hole_size || size >= hole_size - 1) {
> if (hole_end > 0) {
> hole_base = start;
> break;
> } else {
> - hole_base = _ALIGN_DOWN(end - hole_size,
> + hole_base = _ALIGN_DOWN(end - hole_size + 1,
> hole_align);
> }
> }
> }
> free(mem_range);
> if (hole_base == ULONG_MAX) {
> fprintf(stderr, "Could not find a free area of memory of "
> "0x%lx bytes...\n", hole_size);
> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec
_______________________________________________
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec
next prev parent reply other threads:[~2014-03-04 4:03 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-04 0:34 PATCH: bug in locate_hole() Matthew Fleming
2014-03-04 4:03 ` Simon Horman [this message]
2014-03-04 14:55 ` Matthew Fleming
2014-03-05 1:24 ` Baoquan He
2014-03-05 2:52 ` Matthew Fleming
2014-03-06 2:17 ` Simon Horman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20140304040331.GG18200@verge.net.au \
--to=horms@verge.net.au \
--cc=kexec@lists.infradead.org \
--cc=mdf356@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox