From: cinap_lenrek@felloff.net
To: 9fans@9fans.net
Subject: Re: [9fans] linking a program to run at a high address
Date: Thu, 15 May 2014 22:16:56 +0200 [thread overview]
Message-ID: <b89cf29d8e335a2f6fb2b3c529ea5a94@felloff.net> (raw)
In-Reply-To: <a877460eee41ee469461a7c848180901@mikro.quanstro.net>
because the immidiate to CALL instruction is 32bit which get sign
extended to 64bit. but the PC *is* 64bit. its just not that easy
to call directly.
#include <u.h>
#include <libc.h>
void
jump(void *p)
{
((void**)&p)[-1] = p;
}
void
main(int argc, char *argv[])
{
char code[8];
code[0] = 0xCC; /* breakpoint */
jump(code);
}
--
cinap
next prev parent reply other threads:[~2014-05-15 20:16 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-15 19:01 ron minnich
2014-05-15 19:11 ` cinap_lenrek
2014-05-15 19:42 ` erik quanstrom
2014-05-15 20:16 ` cinap_lenrek [this message]
2014-05-15 20:27 ` cinap_lenrek
2014-05-15 20:44 ` ron minnich
2014-05-15 19:17 ` erik quanstrom
2014-05-15 19:18 ` cinap_lenrek
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=b89cf29d8e335a2f6fb2b3c529ea5a94@felloff.net \
--to=cinap_lenrek@felloff.net \
--cc=9fans@9fans.net \
/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).