From: Dan Carpenter <dan.carpenter@oracle.com>
To: Russ Anderson <rja@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Jack Steiner <steiner@sgi.com>,
Dimitri Sivanich <sivanich@sgi.com>,
Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
x86@kernel.org, linux-kernel@vger.kernel.org,
kernel-janitors@vger.kernel.org, rja@americas.sgi.com
Subject: Re: [patch] x86, UV: integer wrap bug in uv_hub_ipi_value()
Date: Tue, 20 Nov 2012 04:28:56 +0000 [thread overview]
Message-ID: <20121120042855.GE6186@mwanda> (raw)
In-Reply-To: <20121120004834.GE5060@sgi.com>
On Mon, Nov 19, 2012 at 06:48:34PM -0600, Russ Anderson wrote:
> On Sat, Nov 17, 2012 at 06:16:11PM +0300, Dan Carpenter wrote:
> > This is a static checker fix. The problem is that we store the bits
> > from "uv_apicid_hibits" into "apicid" (the high 16 bits) but then we
> > shift it 16 bit to the left. "apicid" is an int so it wraps and we lose
> > them.
>
> Is this the complete patch? phys_apicid is an int, but gets
> cast as unsigned long. Doesn't phys_apicid also have to be
> changed to unsigned long? And why ulong instead of uint (on x86_64)?
Uint is 32bit across all arches in linux and unix, according to
wikipedia. The wakeup_secondary_cpu() function pointer takes an int
so I couldn't change the parameter.
>
> I agree with changing signed to unsigned where appropriate, but
> this looks like a partial fix. Am I missing something?
>
I do feel a little embarrassed that I didn't use "unsigned long"
consistently. I just used ulong to make the line a bit shorter, but
I could redo it with "unsigned long" if you want.
regards,
dan carpenter
WARNING: multiple messages have this Message-ID (diff)
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Russ Anderson <rja@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Jack Steiner <steiner@sgi.com>,
Dimitri Sivanich <sivanich@sgi.com>,
Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
x86@kernel.org, linux-kernel@vger.kernel.org,
kernel-janitors@vger.kernel.org, rja@americas.sgi.com
Subject: Re: [patch] x86, UV: integer wrap bug in uv_hub_ipi_value()
Date: Tue, 20 Nov 2012 07:28:56 +0300 [thread overview]
Message-ID: <20121120042855.GE6186@mwanda> (raw)
In-Reply-To: <20121120004834.GE5060@sgi.com>
On Mon, Nov 19, 2012 at 06:48:34PM -0600, Russ Anderson wrote:
> On Sat, Nov 17, 2012 at 06:16:11PM +0300, Dan Carpenter wrote:
> > This is a static checker fix. The problem is that we store the bits
> > from "uv_apicid_hibits" into "apicid" (the high 16 bits) but then we
> > shift it 16 bit to the left. "apicid" is an int so it wraps and we lose
> > them.
>
> Is this the complete patch? phys_apicid is an int, but gets
> cast as unsigned long. Doesn't phys_apicid also have to be
> changed to unsigned long? And why ulong instead of uint (on x86_64)?
Uint is 32bit across all arches in linux and unix, according to
wikipedia. The wakeup_secondary_cpu() function pointer takes an int
so I couldn't change the parameter.
>
> I agree with changing signed to unsigned where appropriate, but
> this looks like a partial fix. Am I missing something?
>
I do feel a little embarrassed that I didn't use "unsigned long"
consistently. I just used ulong to make the line a bit shorter, but
I could redo it with "unsigned long" if you want.
regards,
dan carpenter
next prev parent reply other threads:[~2012-11-20 4:28 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-17 15:16 [patch] x86, UV: integer wrap bug in uv_hub_ipi_value() Dan Carpenter
2012-11-17 15:16 ` Dan Carpenter
2012-11-20 0:48 ` Russ Anderson
2012-11-20 0:48 ` Russ Anderson
2012-11-20 4:28 ` Dan Carpenter [this message]
2012-11-20 4:28 ` Dan Carpenter
2012-11-20 4:55 ` H. Peter Anvin
2012-11-20 4:55 ` H. Peter Anvin
2012-11-20 11:10 ` Alan Cox
2012-11-20 16:27 ` Russ Anderson
2012-11-20 16:27 ` Russ Anderson
2012-11-20 17:09 ` H. Peter Anvin
2012-11-20 17:09 ` H. Peter Anvin
2012-11-20 17:07 ` Russ Anderson
2012-11-20 17:07 ` Russ Anderson
2012-11-21 7:39 ` Dan Carpenter
2012-11-21 7:39 ` Dan Carpenter
2012-12-02 10:44 ` [patch v2] " Dan Carpenter
2012-12-02 10:44 ` Dan Carpenter
2012-12-02 15:33 ` walter harms
2012-12-02 15:33 ` walter harms
2012-12-02 17:28 ` [patch v3] " Dan Carpenter
2012-12-02 17:28 ` Dan Carpenter
2012-12-02 17:35 ` Dan Carpenter
2012-12-02 17:35 ` Dan Carpenter
2012-12-03 7:58 ` [patch v4] " Dan Carpenter
2012-12-03 7:58 ` Dan Carpenter
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=20121120042855.GE6186@mwanda \
--to=dan.carpenter@oracle.com \
--cc=hpa@zytor.com \
--cc=kernel-janitors@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=rja@americas.sgi.com \
--cc=rja@sgi.com \
--cc=sivanich@sgi.com \
--cc=steiner@sgi.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.