From: Laszlo Ersek <lersek@redhat.com>
To: Wei Huang <wei@redhat.com>, qemu-devel@nongnu.org
Cc: qemu-trivial@nongnu.org, mst@redhat.com
Subject: Re: [Qemu-devel] [PATCH 1/1] virtio-rng: fix condition checking on period_ms
Date: Fri, 19 Feb 2016 21:59:19 +0100 [thread overview]
Message-ID: <56C78227.4030207@redhat.com> (raw)
In-Reply-To: <56C781AE.5050004@redhat.com>
On 02/19/16 21:57, Laszlo Ersek wrote:
> On 02/19/16 19:13, Wei Huang wrote:
>> The condition checking on vrng->conf.period_ms appears to be wrong,
>> conflicting with the error comment following it.
>>
>> Signed-off-by: Wei Huang <wei@redhat.com>
>> ---
>> hw/virtio/virtio-rng.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/hw/virtio/virtio-rng.c b/hw/virtio/virtio-rng.c
>> index 473c044..a06427c 100644
>> --- a/hw/virtio/virtio-rng.c
>> +++ b/hw/virtio/virtio-rng.c
>> @@ -149,7 +149,7 @@ static void virtio_rng_device_realize(DeviceState *dev, Error **errp)
>> VirtIORNG *vrng = VIRTIO_RNG(dev);
>> Error *local_err = NULL;
>>
>> - if (!vrng->conf.period_ms > 0) {
>> + if (!(vrng->conf.period_ms > 0)) {
>> error_setg(errp, "'period' parameter expects a positive integer");
>> return;
>> }
>>
>
> The current condition is absolutely weird, but I think it happens to
> work correctly:
>
> Period_ms has type uint32_t. If it is positive, then !period_ms is zero.
> 0>0 is false, hence the error message is not printed.
>
> If period_ms is zero, then !period_ms is 1. 1>0 is true, hence the error
> message is printed.
>
> I would rewrite the check as
>
> if (vrng->conf.period_ms == 0) {
> error_setg(...)
... actually, what the heck are you looking at? :) This has been fixed
up in:
commit a3a292c420d2fec3c07a7ca56fbb064cd57a298a
Author: Amit Shah <amit.shah@redhat.com>
Date: Thu Dec 11 13:17:42 2014 +0530
virtio-rng: fix check for period_ms validity
Thanks
Laszlo
next prev parent reply other threads:[~2016-02-19 20:59 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-19 18:13 [Qemu-devel] [PATCH 1/1] virtio-rng: fix condition checking on period_ms Wei Huang
2016-02-19 20:57 ` Laszlo Ersek
2016-02-19 20:59 ` Laszlo Ersek [this message]
2016-02-19 21:07 ` Wei Huang
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=56C78227.4030207@redhat.com \
--to=lersek@redhat.com \
--cc=mst@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=qemu-trivial@nongnu.org \
--cc=wei@redhat.com \
/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).