DPDK patches and discussions
 help / color / mirror / Atom feed
From: tgw_team(腾讯网关团队) <tgw_team@tencent.com>
To: Andrew Rybchenko <arybchenko@solarflare.com>,
	Tencent TGW team <quzeyao@gmail.com>,
	Thomas Monjalon <thomas@monjalon.net>,
	Ferruh Yigit <ferruh.yigit@intel.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] [PATCH] rte_ethdev: fix unsafe memory access by calling RX callback.
Date: Wed, 4 Mar 2020 16:26:14 +0000
Message-ID: <3729706a2990414f9bfd40183d07655f@tencent.com> (raw)
In-Reply-To: <61a6b7d5533643d692c40dc0ab1a2cdc@tencent.com>

As a newcomer, I'm sorry for my mistakes. I will try to do better in the future.

>On 3/4/20 5:05 PM, Tencent TGW team wrote:
>> When compiling with -O0,
>> the compiler does not optimize two memory accesses into one.
>> Leads to accessing a null pointer when calling the RX callback.
>> The way to access the TX callback is correct.
>
>It looks like the patch is not passed through check-git-log.sh.
>RX -> Rx, TX -> Tx

Sorry, I will check and refine in patch v2.

>>
>> 
>> Signed-off-by: Tencent TGW team <tgw_team@tencent.com>

>If I'm not mistaken, it must be a person here, not team.

Is there any way to submit patches as a team?

>> ---
>>  lib/librte_ethdev/rte_ethdev.h | 6 ++----
>>  1 file changed, 2 insertions(+), 4 deletions(-)
>> 
>> diff --git a/lib/librte_ethdev/rte_ethdev.h b/lib/librte_ethdev/rte_ethdev.h
>> index d1a593ad1..35eb580ff 100644
>> --- a/lib/librte_ethdev/rte_ethdev.h
>> +++ b/lib/librte_ethdev/rte_ethdev.h
>> @@ -4388,10 +4388,8 @@ rte_eth_rx_burst(uint16_t port_id, uint16_t queue_id,
>>                                     rx_pkts, nb_pkts);
>>  
>>  #ifdef RTE_ETHDEV_RXTX_CALLBACKS
>> -     if (unlikely(dev->post_rx_burst_cbs[queue_id] != NULL)) {
>> -             struct rte_eth_rxtx_callback *cb =
>> -                             dev->post_rx_burst_cbs[queue_id];
>> -
>> +     struct rte_eth_rxtx_callback *cb = dev->post_rx_burst_cbs[queue_id];
>> +     if (unlikely(cb != NULL)) {
>>                do {
>>                        nb_rx = cb->fn.rx(port_id, queue_id, rx_pkts, nb_rx,
>>                                                nb_pkts, cb->param);
>> 

>Sorry, but I don't understand. I don't see the difference in
>potential NULL pointer deference above. What is the compiler? Version?

gcc version 7.4.0
I think this problem has nothing to do with the compiler version.

>Or is it a race condition with queue post Rx burst callback
>removal  while traffic is running?

You're right.

  parent reply	other threads:[~2020-03-04 16:26 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-04 14:05 Tencent TGW team
2020-03-04 14:16 ` Andrew Rybchenko
     [not found]   ` <61a6b7d5533643d692c40dc0ab1a2cdc@tencent.com>
2020-03-04 16:26     ` tgw_team(腾讯网关团队) [this message]
2020-03-04 16:15 ` Stephen Hemminger
2020-03-04 16:38   ` [dpdk-dev] [PATCH] rte_ethdev: fix unsafe memory access by calling RX callback.(Internet mail) tgw_team(腾讯网关团队)
2020-03-04 17:37     ` Stephen Hemminger
2020-03-04 17:44       ` [dpdk-dev] [PATCH] rte_ethdev: fix unsafe memory access by calling RX callback tgw_team(腾讯网关团队)
2020-03-04 17:33 ` [dpdk-dev] [PATCH v2] rte_ethdev: safer memory access by calling Rx callback ZY Qiu
2020-03-04 17:56   ` Stephen Hemminger
2020-03-04 18:31     ` tgw_team(腾讯网关团队)
2020-03-05  9:19   ` Bruce Richardson
2020-03-05 11:27     ` Ananyev, Konstantin
2020-03-05 14:23       ` tgw_team(腾讯网关团队)
2020-03-05 14:47       ` Liang, Ma
2020-03-05 15:19         ` Ananyev, Konstantin
2020-03-05 15:42           ` Liang, Ma
2020-03-05 16:47   ` [dpdk-dev] [PATCH v3] rte_ethdev: safer memory access by calling Rx/Tx callback ZY Qiu
2020-03-05 17:23     ` Jerin Jacob
2020-03-11 12:22     ` Ananyev, Konstantin
2020-03-11 12:26       ` Jerin Jacob
2020-10-01 15:14         ` Ferruh Yigit

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=3729706a2990414f9bfd40183d07655f@tencent.com \
    --to=tgw_team@tencent.com \
    --cc=arybchenko@solarflare.com \
    --cc=dev@dpdk.org \
    --cc=ferruh.yigit@intel.com \
    --cc=quzeyao@gmail.com \
    --cc=thomas@monjalon.net \
    /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

DPDK patches and discussions

This inbox may be cloned and mirrored by anyone:

	git clone --mirror https://inbox.dpdk.org/dev/0 dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 dev dev/ https://inbox.dpdk.org/dev \
		dev@dpdk.org
	public-inbox-index dev

Example config snippet for mirrors.
Newsgroup available over NNTP:
	nntp://inbox.dpdk.org/inbox.dpdk.dev


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git