From: Yao Qi <qiyaoltc@gmail.com>
To: Yao Qi <qiyaoltc@gmail.com>,
"gdb-patches@sourceware.org" <gdb-patches@sourceware.org>
Subject: Re: [PATCH] Set unknown_syscall differently on arm linux
Date: Thu, 30 Jun 2016 07:52:00 -0000 [thread overview]
Message-ID: <CAH=s-PNROPwycGYFZ1_Duc4SRN4vCXHuuX+ootCT3bMD5SOEkw@mail.gmail.com> (raw)
In-Reply-To: <20160629174103.GW4685@vapier.lan>
On Wed, Jun 29, 2016 at 6:41 PM, Mike Frysinger <vapier@gentoo.org> wrote:
> On 28 Jun 2016 10:26, Yao Qi wrote:
>> Currently, we use 123456789 as unknown or illegal syscall number, and
>> expect program return ENOSYS. Although 123456789 is an illegal syscall
>> number on arm linux, kernel sends SIGILL rather than returns -ENOSYS.
>
> err, what ? calling random syscalls should not result in signals being
> generated (ignoring obvious ones like __NR_kill). is the kernel broken ?
> i think this needs more investigation & explanation.
I checked kernel source arch/arm/kernel/traps.c:arm_syscall, and that is how
I get the knowledge that kernel doesn't raise SIGIILL if sysno is within
0xf0001..0xf07ff. That is intentional, but I don't know why arm kernel behaves
this way.
--
Yao (齐尧)
next prev parent reply other threads:[~2016-06-30 7:52 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-28 9:26 Yao Qi
2016-06-29 9:53 ` Pedro Alves
2016-06-29 13:56 ` Yao Qi
2016-06-29 17:41 ` Mike Frysinger
2016-06-30 7:52 ` Yao Qi [this message]
2016-06-30 12:58 ` Mike Frysinger
2016-06-30 14:48 ` Yao Qi
2016-07-04 2:20 ` Mike Frysinger
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='CAH=s-PNROPwycGYFZ1_Duc4SRN4vCXHuuX+ootCT3bMD5SOEkw@mail.gmail.com' \
--to=qiyaoltc@gmail.com \
--cc=gdb-patches@sourceware.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