From: losemyheaven@qq.com (=?gb18030?B?wuS62w==?=)
To: kernelnewbies@lists.kernelnewbies.org
Subject: A question about kernel real-mode code's LMA & VMA
Date: Sat, 7 May 2016 14:40:27 +0800 [thread overview]
Message-ID: <tencent_5688499A3E55ADF12614066C@qq.com> (raw)
Hi,
The following is extracted from Documentation/x86/boot.txt,
which show's memory map when booting a kernel.
117 ~ ~ 118 | Protected-mode kernel | 119 100000 +------------------------+ 120 | I/O memory hole | 121 0A0000 +------------------------+ 122 | Reserved for BIOS | Leave as much as possible unused 123 ~ ~ 124 | Command line | (Can also be below the X+10000 mark) 125 X+10000 +------------------------+ 126 | Stack/heap | For use by the kernel real-mode code. 127 X+08000 +------------------------+ 128 | Kernel setup | The kernel real-mode code. 129 | Kernel boot sector | The kernel legacy boot sector. 130 X +------------------------+ 131 | Boot loader | <- Boot sector entry point 0000:7C00 132 001000 +------------------------+ 133 | Reserved for MBR/BIOS | 134 000800 +------------------------+ 135 | Typically used by MBR | 136 000600 +------------------------+ 137 | BIOS use only | 138 000000 +------------------------+where the address X is as low as the design of the boot loader 141 permits.
The address X is not determined by kernel, so the kernel real-mode code's VMA may not equal to LMA, how kernel solved it??
One more question, in ld script, does the location counter ".", represent VMA??
Thanks.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20160507/2f52d155/attachment.html
reply other threads:[~2016-05-07 6:40 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=tencent_5688499A3E55ADF12614066C@qq.com \
--to=losemyheaven@qq.com \
--cc=kernelnewbies@lists.kernelnewbies.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 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).