From: Andrew Morton <akpm@osdl.org>
To: Jakub Jelinek <jakub@redhat.com>
Cc: roland@redhat.com, mtk-lkml@gmx.net, torvalds@osdl.org,
drepper@redhat.com, linux-kernel@vger.kernel.org,
michael.kerrisk@gmx.net, tonnerre@thundrix.ch
Subject: Re: [PATCH] waitid system call
Date: Mon, 30 Aug 2004 23:40:57 -0700 [thread overview]
Message-ID: <20040830234057.2bdec761.akpm@osdl.org> (raw)
In-Reply-To: <20040831062656.GU11465@devserv.devel.redhat.com>
Jakub Jelinek <jakub@redhat.com> wrote:
>
> On Mon, Aug 30, 2004 at 11:04:46PM -0700, Roland McGrath wrote:
> > + /*
> > + * For a WNOHANG return, clear out all the fields
> > + * we would set so the user can easily tell the
> > + * difference.
> > + */
> > + if (!retval)
> > + retval = put_user(0, &infop->si_signo);
> > + if (!retval)
> > + retval = put_user(0, &infop->si_errno);
> > + if (!retval)
> > + retval = put_user(0, &infop->si_code);
> > + if (!retval)
> > + retval = put_user(0, &infop->si_pid);
> > + if (!retval)
> > + retval = put_user(0, &infop->si_uid);
> > + if (!retval)
> > + retval = put_user(0, &infop->si_status);
>
> Is it really necessary to check the exit code after each put_user?
> if (!retval && access_ok(VERIFY_WRITE, infop, sizeof(*infop)))) {
> retval = __put_user(0, &infop->si_signo);
> retval |= __put_user(0, &infop->si_errno);
> retval |= __put_user(0, &infop->si_code);
> retval |= __put_user(0, &infop->si_pid);
> retval |= __put_user(0, &infop->si_uid);
> retval |= __put_user(0, &infop->si_status);
> }
> is what kernel usually does when filling multiple structure members.
I don't think it matters much. Taking seven trips into the fault handler
where one would do seems a bit dumb though.
next prev parent reply other threads:[~2004-08-31 6:43 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-08-15 23:03 [PATCH] waitid system call Roland McGrath
2004-08-16 5:40 ` Roland McGrath
2004-08-16 17:15 ` Michael Kerrisk
2004-08-16 21:12 ` Roland McGrath
2004-08-19 17:20 ` Michael Kerrisk
2004-08-19 20:53 ` Roland McGrath
2004-08-20 6:00 ` Michael Kerrisk
2004-08-20 9:02 ` Michael Kerrisk
2004-08-20 20:04 ` Roland McGrath
2004-08-24 11:51 ` Michael Kerrisk
2004-08-31 6:04 ` Roland McGrath
2004-08-31 6:26 ` Jakub Jelinek
2004-08-31 6:37 ` Roland McGrath
2004-08-31 6:40 ` Andrew Morton [this message]
2004-08-31 15:53 ` Bill Davidsen
2004-08-31 18:26 ` Linus Torvalds
2004-08-31 23:51 ` Roland McGrath
2004-09-01 11:31 ` Michael Kerrisk
2004-08-31 7:22 ` Michael Kerrisk
2004-08-22 8:53 ` Tonnerre
[not found] <2tCiy-8pK-13@gated-at.bofh.it>
2004-08-16 0:03 ` Andi Kleen
2004-08-16 2:10 ` Roland McGrath
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=20040830234057.2bdec761.akpm@osdl.org \
--to=akpm@osdl.org \
--cc=drepper@redhat.com \
--cc=jakub@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=michael.kerrisk@gmx.net \
--cc=mtk-lkml@gmx.net \
--cc=roland@redhat.com \
--cc=tonnerre@thundrix.ch \
--cc=torvalds@osdl.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