From: "André Almeida" <andrealmeid@collabora.com>
To: Thomas Gleixner <tglx@linutronix.de>,
LKML <linux-kernel@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
Adhemerval Zanella <adhemerval.zanella@linaro.org>,
Lukasz Majewski <lukma@denx.de>,
Florian Weimer <fweimer@redhat.com>,
Carlos O'Donell <carlos@redhat.com>,
"Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>,
Davidlohr Bueso <dave@stgolabs.net>,
Ingo Molnar <mingo@kernel.org>,
Darren Hart <dvhart@infradead.org>,
Andrei Vagin <avagin@gmail.com>,
Kurt Kanzenbach <kurt@linutronix.de>,
kernel@collabora.com
Subject: Re: [patch 3/6] futex: Get rid of the val2 conditional dance
Date: Fri, 23 Apr 2021 20:21:58 -0300 [thread overview]
Message-ID: <5817ec9e-9e80-79ef-d09c-6717b0816963@collabora.com> (raw)
In-Reply-To: <87r1j0vdev.ffs@nanos.tec.linutronix.de>
Às 19:34 de 23/04/21, Thomas Gleixner escreveu:
> On Fri, Apr 23 2021 at 18:40, André Almeida wrote:
>>>
>>> - return do_futex(uaddr, op, val, tp, uaddr2, val2, val3);
>>> + return do_futex(uaddr, op, val, tp, uaddr2, (unsigned long)utime, val3);
>>
>> Given do_futex()'s type signature, I think it makes more sense to cast
>> utime to u32.
>
> It's a pointer which you better force cast to unsigned long first.
>
> So the explicit thing would be '(u32)(unsigned long) utime' which is
> what the val2 dance stupidly did with 'int'
>
> val2 = (int) (unsigned long) utime;
>
> But with doing it at function call argument it's implicit, because the
>
> unsigned long to u32 conversion is well defined
>
> while
>
> (u32)ptr
>
> is only well defined on 32bit.
>
I see, thank you for the clarification!
> Thanks,
>
> tglx
>
next prev parent reply other threads:[~2021-04-23 23:22 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-22 19:44 [patch 0/6] futex: Bugfixes and FUTEX_LOCK_PI2 Thomas Gleixner
2021-04-22 19:44 ` [patch 1/6] Revert 337f13046ff0 ("futex: Allow FUTEX_CLOCK_REALTIME with FUTEX_WAIT op") Thomas Gleixner
2021-05-06 18:14 ` [tip: locking/urgent] " tip-bot2 for Thomas Gleixner
2021-04-22 19:44 ` [patch 2/6] futex: Do not apply time namespace adjustment on FUTEX_LOCK_PI Thomas Gleixner
2021-05-06 18:14 ` [tip: locking/urgent] " tip-bot2 for Thomas Gleixner
2021-04-22 19:44 ` [patch 3/6] futex: Get rid of the val2 conditional dance Thomas Gleixner
2021-04-23 21:40 ` André Almeida
2021-04-23 22:34 ` Thomas Gleixner
2021-04-23 23:21 ` André Almeida [this message]
2021-05-06 18:20 ` [tip: locking/urgent] " tip-bot2 for Thomas Gleixner
2021-04-22 19:44 ` [patch 4/6] futex: Make syscall entry points less convoluted Thomas Gleixner
2021-05-06 18:20 ` [tip: locking/urgent] " tip-bot2 for Thomas Gleixner
2021-04-22 19:44 ` [patch 5/6] futex: Prepare futex_lock_pi() for runtime clock selection Thomas Gleixner
2021-04-23 9:34 ` Lukasz Majewski
2021-04-23 10:08 ` Thomas Gleixner
2021-06-23 8:19 ` [tip: locking/core] " tip-bot2 for Thomas Gleixner
2021-04-22 19:44 ` [patch 6/6] futex: Provide FUTEX_LOCK_PI2 to support " Thomas Gleixner
2021-04-23 22:20 ` André Almeida
2021-04-23 22:36 ` Thomas Gleixner
2021-06-23 8:19 ` [tip: locking/core] " tip-bot2 for Thomas Gleixner
2021-05-05 12:59 ` [patch 0/6] futex: Bugfixes and FUTEX_LOCK_PI2 Peter Zijlstra
2021-05-05 13:51 ` Kurt Kanzenbach
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=5817ec9e-9e80-79ef-d09c-6717b0816963@collabora.com \
--to=andrealmeid@collabora.com \
--cc=adhemerval.zanella@linaro.org \
--cc=avagin@gmail.com \
--cc=carlos@redhat.com \
--cc=dave@stgolabs.net \
--cc=dvhart@infradead.org \
--cc=fweimer@redhat.com \
--cc=kernel@collabora.com \
--cc=kurt@linutronix.de \
--cc=linux-kernel@vger.kernel.org \
--cc=lukma@denx.de \
--cc=mingo@kernel.org \
--cc=mtk.manpages@gmail.com \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
/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).