From: Khalid Aziz <khalid.aziz@hp.com>
To: Vivek Goyal <vgoyal@redhat.com>
Cc: kexec@lists.infradead.org, horms@verge.net.au,
Dave Young <dyoung@redhat.com>
Subject: Re: [PATCH]kdump: pass noefi and acpi_rsdp= to 2nd kernel
Date: Fri, 14 Sep 2012 14:32:31 -0600 [thread overview]
Message-ID: <5053945F.9060107@hp.com> (raw)
In-Reply-To: <20120913133827.GB4396@redhat.com>
On 09/13/2012 07:38 AM, Vivek Goyal wrote:
> So what does this mean? Second kernel assumes the regular BIOS and tries
> to initialize that way? That sounds broken or is it just fine given
> the fact we are anyway not planning to call into any of the efi services.
> But what about memory maps, ACPI tables etc.
Hi Vivek,
My understanding on x86 side is not as clear as on ia64 side of kexec.
From my reading of the code, second kernel seems to assume a regular
BIOS. It searches through EBDA or upper memory region E0000h-FFFFFh to
find RSDP, if an RSDP pointer was not passed to the second kernel. This
works on my EFI machine which also implements a BIOS compatibility
layer. I wonder how it works on pure EFI machines. Do pure EFI machines
not implement, say EBDA? If yes, acpi_find_root_pointer() should fail
tofind RSDP.As for memory map, all I can find are reference to e820
memory map which again assumes a BIOS but most EFI implementations I
have come across implement a BIOS compatibility layer, so this will work
still. I will look some more into this.
--
Khalid
_______________________________________________
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec
next prev parent reply other threads:[~2012-09-14 20:32 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-05 5:44 [PATCH]kdump: pass noefi and acpi_rsdp= to 2nd kernel Dave Young
2012-09-05 7:45 ` Simon Horman
2012-09-06 2:48 ` Dave Young
2012-09-05 13:18 ` Vivek Goyal
2012-09-06 2:58 ` Dave Young
2012-09-06 20:46 ` Vivek Goyal
2012-09-05 23:09 ` Khalid Aziz
2012-09-06 3:18 ` Dave Young
2012-09-06 17:57 ` Khalid Aziz
2012-09-07 8:56 ` Dave Young
2012-09-07 14:37 ` Khalid Aziz
2012-09-13 13:38 ` Vivek Goyal
2012-09-14 20:32 ` Khalid Aziz [this message]
2012-09-20 7:49 ` Eric W. Biederman
2012-09-21 22:50 ` Khalid Aziz
2012-09-12 2:35 ` Dave Young
2012-10-18 3:12 ` Dave Young
2012-10-18 14:59 ` Khalid Aziz
2012-10-22 2:05 ` Dave Young
2012-09-06 20:24 ` Vivek Goyal
2012-09-07 14:32 ` Khalid Aziz
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=5053945F.9060107@hp.com \
--to=khalid.aziz@hp.com \
--cc=dyoung@redhat.com \
--cc=horms@verge.net.au \
--cc=kexec@lists.infradead.org \
--cc=vgoyal@redhat.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;
as well as URLs for NNTP newsgroup(s).