From: Doug Ledford <dledford@redhat.com>
To: Dan Carpenter <dan.carpenter@oracle.com>,
Mike Marciniszyn <mike.marciniszyn@intel.com>
Cc: Dennis Dalessandro <dennis.dalessandro@intel.com>,
Sean Hefty <sean.hefty@intel.com>,
Hal Rosenstock <hal.rosenstock@gmail.com>,
linux-rdma@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] IB/hfi1: Fix a wrapping test (make it less strict)
Date: Mon, 23 Oct 2017 15:05:16 +0000 [thread overview]
Message-ID: <1508771116.3325.0.camel@redhat.com> (raw)
In-Reply-To: <20171013105559.tqzh6jhcnvmqhdwy@mwanda>
On Fri, 2017-10-13 at 13:56 +0300, Dan Carpenter wrote:
> The "2 * UINT_MAX" overflows so the test is essentially doing this:
>
> if ((u64)(ts - cce->timestamp) > UINT_MAX - 1) {
>
> I've changed it to a 64bit type.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> Not tested.
>
> diff --git a/drivers/infiniband/hw/hfi1/mad.c
> b/drivers/infiniband/hw/hfi1/mad.c
> index f4c0ffc040cc..3aeea8afd44f 100644
> --- a/drivers/infiniband/hw/hfi1/mad.c
> +++ b/drivers/infiniband/hw/hfi1/mad.c
> @@ -3781,7 +3781,7 @@ static int __subn_get_opa_hfi1_cong_log(struct
> opa_smp *smp, u32 am,
> * required to wrap the counter are supposed to
> * be zeroed (CA10-49 IBTA, release 1.2.1, V1).
> */
> - if ((u64)(ts - cce->timestamp) > (2 * UINT_MAX))
> + if ((u64)(ts - cce->timestamp) > (2ULL * UINT_MAX))
> continue;
> memcpy(cong_log->events[i].local_qp_cn_entry, &cce-
> >lqpn, 3);
> memcpy(cong_log-
> >events[i].remote_qp_number_cn_entry,
Denny, I'm looking for feedback from you on this patch. This fixes a
bug, my only concern is that the code used to work with the bug, could
this make the code not work?
--
Doug Ledford <dledford@redhat.com>
GPG KeyID: B826A3330E572FDD
Key fingerprint = AE6B 1BDA 122B 23B4 265B 1274 B826 A333 0E57 2FDD
WARNING: multiple messages have this Message-ID (diff)
From: Doug Ledford <dledford@redhat.com>
To: Dan Carpenter <dan.carpenter@oracle.com>,
Mike Marciniszyn <mike.marciniszyn@intel.com>
Cc: Dennis Dalessandro <dennis.dalessandro@intel.com>,
Sean Hefty <sean.hefty@intel.com>,
Hal Rosenstock <hal.rosenstock@gmail.com>,
linux-rdma@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] IB/hfi1: Fix a wrapping test (make it less strict)
Date: Mon, 23 Oct 2017 11:05:16 -0400 [thread overview]
Message-ID: <1508771116.3325.0.camel@redhat.com> (raw)
In-Reply-To: <20171013105559.tqzh6jhcnvmqhdwy@mwanda>
On Fri, 2017-10-13 at 13:56 +0300, Dan Carpenter wrote:
> The "2 * UINT_MAX" overflows so the test is essentially doing this:
>
> if ((u64)(ts - cce->timestamp) > UINT_MAX - 1) {
>
> I've changed it to a 64bit type.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> Not tested.
>
> diff --git a/drivers/infiniband/hw/hfi1/mad.c
> b/drivers/infiniband/hw/hfi1/mad.c
> index f4c0ffc040cc..3aeea8afd44f 100644
> --- a/drivers/infiniband/hw/hfi1/mad.c
> +++ b/drivers/infiniband/hw/hfi1/mad.c
> @@ -3781,7 +3781,7 @@ static int __subn_get_opa_hfi1_cong_log(struct
> opa_smp *smp, u32 am,
> * required to wrap the counter are supposed to
> * be zeroed (CA10-49 IBTA, release 1.2.1, V1).
> */
> - if ((u64)(ts - cce->timestamp) > (2 * UINT_MAX))
> + if ((u64)(ts - cce->timestamp) > (2ULL * UINT_MAX))
> continue;
> memcpy(cong_log->events[i].local_qp_cn_entry, &cce-
> >lqpn, 3);
> memcpy(cong_log-
> >events[i].remote_qp_number_cn_entry,
Denny, I'm looking for feedback from you on this patch. This fixes a
bug, my only concern is that the code used to work with the bug, could
this make the code not work?
--
Doug Ledford <dledford@redhat.com>
GPG KeyID: B826A3330E572FDD
Key fingerprint = AE6B 1BDA 122B 23B4 265B 1274 B826 A333 0E57 2FDD
next prev parent reply other threads:[~2017-10-23 15:05 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-13 10:56 [PATCH] IB/hfi1: Fix a wrapping test (make it less strict) Dan Carpenter
2017-10-13 10:56 ` Dan Carpenter
2017-10-23 15:05 ` Doug Ledford [this message]
2017-10-23 15:05 ` Doug Ledford
[not found] ` <1508771116.3325.0.camel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2017-10-23 17:57 ` Dennis Dalessandro
2017-10-23 17:57 ` Dennis Dalessandro
2017-10-23 18:33 ` Doug Ledford
2017-10-23 18:33 ` Doug Ledford
2017-10-23 19:04 ` Jason Gunthorpe
2017-10-23 19:04 ` Jason Gunthorpe
2017-10-24 19:54 ` Marciniszyn, Mike
[not found] ` <32E1700B9017364D9B60AED9960492BC3443EB1C-RjuIdWtd+YbTXloPLtfHfbfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2017-10-24 20:02 ` Jason Gunthorpe
2017-10-24 20:02 ` Jason Gunthorpe
[not found] ` <20171024200216.GA15994-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
2017-10-24 20:03 ` Marciniszyn, Mike
2017-10-24 20:03 ` Marciniszyn, Mike
2017-10-25 5:27 ` Dan Carpenter
2017-10-25 5:27 ` Dan Carpenter
2017-10-25 5:14 ` Dan Carpenter
2017-10-25 5:14 ` 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=1508771116.3325.0.camel@redhat.com \
--to=dledford@redhat.com \
--cc=dan.carpenter@oracle.com \
--cc=dennis.dalessandro@intel.com \
--cc=hal.rosenstock@gmail.com \
--cc=kernel-janitors@vger.kernel.org \
--cc=linux-rdma@vger.kernel.org \
--cc=mike.marciniszyn@intel.com \
--cc=sean.hefty@intel.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 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.