From: "H. Peter Anvin" <hpa@zytor.com>
To: Vivek Goyal <vgoyal@redhat.com>
Cc: kexec <kexec@lists.infradead.org>, Ingo Molnar <mingo@elte.hu>,
Yinghai Lu <yinghai@kernel.org>,
caiqian@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: kexec load failure introduced by "x86, memblock: Replace e820_/_early string with memblock_"
Date: Mon, 27 Sep 2010 20:46:42 -0700 [thread overview]
Message-ID: <4CA16522.8060107@zytor.com> (raw)
In-Reply-To: <20100928005358.GA6456@redhat.com>
On 09/27/2010 05:53 PM, Vivek Goyal wrote:
>
> Actually, hardcoding the upper limit to 4G is probably not the best idea.
> Kexec loads the the relocatable binary (purgatory) and I remember that
> one of the generated relocation type was signed 32 bit and allowed max value
> to be 2G only. So IIRC, purgatory code always needed to be loaded below 2G.
>
> I liked HPA's other idea better of introducing memblock_find_in_range_lowest()
> so that we search bottom up and not rely on a specific upper limit.
>
No, it's just another crappy hack which is broken in the same way. It's
better than open-coding, but it's still a hack.
The Right Thing[TM] to do is for kexec to communicate the topmost
address it wants to this code, so it has both the upper and the lower
boundaries available to it instead of just one.
-hpa
--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.
_______________________________________________
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec
WARNING: multiple messages have this Message-ID (diff)
From: "H. Peter Anvin" <hpa@zytor.com>
To: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>, Ingo Molnar <mingo@elte.hu>,
kexec <kexec@lists.infradead.org>,
caiqian@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: kexec load failure introduced by "x86, memblock: Replace e820_/_early string with memblock_"
Date: Mon, 27 Sep 2010 20:46:42 -0700 [thread overview]
Message-ID: <4CA16522.8060107@zytor.com> (raw)
In-Reply-To: <20100928005358.GA6456@redhat.com>
On 09/27/2010 05:53 PM, Vivek Goyal wrote:
>
> Actually, hardcoding the upper limit to 4G is probably not the best idea.
> Kexec loads the the relocatable binary (purgatory) and I remember that
> one of the generated relocation type was signed 32 bit and allowed max value
> to be 2G only. So IIRC, purgatory code always needed to be loaded below 2G.
>
> I liked HPA's other idea better of introducing memblock_find_in_range_lowest()
> so that we search bottom up and not rely on a specific upper limit.
>
No, it's just another crappy hack which is broken in the same way. It's
better than open-coding, but it's still a hack.
The Right Thing[TM] to do is for kexec to communicate the topmost
address it wants to this code, so it has both the upper and the lower
boundaries available to it instead of just one.
-hpa
--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.
next prev parent reply other threads:[~2010-09-28 3:47 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1909915255.2046011285586388234.JavaMail.root@zmail06.collab.prod.int.phx2.redhat.com>
2010-09-27 11:21 ` kexec load failure introduced by "x86, memblock: Replace e820_/_early string with memblock_" caiqian
2010-09-27 11:21 ` caiqian
2010-09-27 22:22 ` Yinghai Lu
2010-09-27 22:22 ` Yinghai Lu
2010-09-27 22:50 ` H. Peter Anvin
2010-09-27 22:50 ` H. Peter Anvin
2010-09-27 23:20 ` Yinghai Lu
2010-09-27 23:20 ` Yinghai Lu
2010-09-27 23:26 ` H. Peter Anvin
2010-09-27 23:26 ` H. Peter Anvin
2010-09-27 23:32 ` Yinghai Lu
2010-09-27 23:32 ` Yinghai Lu
2010-09-27 23:34 ` H. Peter Anvin
2010-09-27 23:34 ` H. Peter Anvin
2010-09-27 23:41 ` Yinghai Lu
2010-09-27 23:41 ` Yinghai Lu
2010-09-28 0:53 ` Vivek Goyal
2010-09-28 0:53 ` Vivek Goyal
2010-09-28 2:41 ` Yinghai Lu
2010-09-28 2:41 ` Yinghai Lu
2010-09-28 3:46 ` H. Peter Anvin [this message]
2010-09-28 3:46 ` H. Peter Anvin
2010-09-28 7:14 ` Yinghai Lu
2010-09-28 7:14 ` Yinghai Lu
2010-09-28 14:01 ` Vivek Goyal
2010-09-28 14:01 ` Vivek Goyal
2010-09-28 13:54 ` Vivek Goyal
2010-09-28 13:54 ` Vivek Goyal
[not found] <1346740216.2003261285553562018.JavaMail.root@zmail06.collab.prod.int.phx2.redhat.com>
2010-09-27 2:42 ` caiqian
2010-09-27 2:42 ` caiqian
2010-09-27 5:58 ` Yinghai Lu
2010-09-27 5:58 ` Yinghai Lu
2010-09-27 6:31 ` Yinghai Lu
2010-09-27 6:31 ` Yinghai Lu
2010-09-27 9:16 ` CAI Qian
2010-09-27 9:16 ` CAI Qian
[not found] <1834151968.1996101285512089968.JavaMail.root@zmail06.collab.prod.int.phx2.redhat.com>
2010-09-26 14:47 ` caiqian
2010-09-26 14:47 ` caiqian
2010-09-26 19:42 ` Yinghai Lu
2010-09-26 19:42 ` Yinghai Lu
[not found] <1614106428.1991831285470588200.JavaMail.root@zmail06.collab.prod.int.phx2.redhat.com>
2010-09-26 3:11 ` caiqian
2010-09-26 3:11 ` caiqian
2010-09-26 6:44 ` Yinghai Lu
2010-09-26 6:44 ` Yinghai Lu
2010-09-26 6:55 ` CAI Qian
2010-09-26 6:55 ` CAI Qian
2010-09-26 6:56 ` Yinghai Lu
2010-09-26 6:56 ` Yinghai Lu
2010-09-26 10:37 ` CAI Qian
2010-09-26 10:37 ` CAI Qian
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=4CA16522.8060107@zytor.com \
--to=hpa@zytor.com \
--cc=caiqian@redhat.com \
--cc=kexec@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=vgoyal@redhat.com \
--cc=yinghai@kernel.org \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.