From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Chi, Xiaobo (Nokia - CN/Hangzhou)" Subject: Re: [PATCH] vhost: eventfd_link's minor number shall be specified Date: Mon, 9 Nov 2015 10:19:54 +0000 Message-ID: References: <1446789877-11656-1-git-send-email-xiaobo.chi@nokia.com> <20151109042237.GK2326@yliu-dev.sh.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Cc: "dev@dpdk.org" , "changchun.ouyang@intel.com" To: "Chi, Xiaobo (Nokia - CN/Hangzhou)" , "EXT Yuanhan Liu" Return-path: Received: from demumfd001.nsn-inter.net (demumfd001.nsn-inter.net [93.183.12.32]) by dpdk.org (Postfix) with ESMTP id A00243979 for ; Mon, 9 Nov 2015 11:21:59 +0100 (CET) In-Reply-To: Content-Language: en-US List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Hi, And following is a test by me, we can see that if I firstly insert my kmod_= test.ko, then insert eventfd_link.ko, error will happen with hint " Device = or resource busy". This is because the default minor device number, 0, has = been occupied by my kmod_test.ko . root@distro:~/test$ lsmod Module Size Used by kmod_test 927 0=20 vboxsf 35930 4=20 vboxguest 222130 1 vboxsf microcode 10315 0=20 autofs4 25051 0=20 root@distro:~/test$ modinfo kmod_test modinfo: ERROR: Module kmod_test not found. root@distro:~/test$ modinfo kmod_test.ko filename: /root/test/kmod_test.ko alias: devname:test description: my test author: Xiaobo Chi license: GPL v2 version: 0.0.1 srcversion: C2BDEBC81A17F8197C7C44A depends: =20 vermagic: 3.18.9-pc64-distro.git-v1.7 SMP mod_unload=20 root@distro:~/test$ dmesg -c root@distro:~/test$ ls eventfd_link.ko kmod_test.ko kmod_test.mod.o main Makefile M= odule.symvers kmod_test.c kmod_test.mod.c kmod_test.o main.c modules.order root@distro:~/test$ insmod ./eventfd_link.ko=20 insmod: ERROR: could not insert module ./eventfd_link.ko: Device or resourc= e busy root@distro:~/test$ dmesg -c brgs, Xiaobo Chi -----Original Message----- From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of EXT Chi, Xiaobo (Nokia= - CN/Hangzhou) Sent: Monday, November 09, 2015 6:03 PM To: EXT Yuanhan Liu Cc: dev@dpdk.org; changchun.ouyang@intel.com Subject: Re: [dpdk-dev] [PATCH] vhost: eventfd_link's minor number shall be= specified Hi, For miscdevices, the major device_no is same, so the minor device_no should= be set to ditinguish different misc devices; if not set the minor, it may= fail while insmod due to the default minor value, 0, has been used by othe= r miscdevice. MISC_DYNAMIC_MINOR means to let Linux kernel dynamically assi= gn one minor devide number while loading. You can refer to the kni_misc.c Brgs, Chi Xiaobo -----Original Message----- From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of EXT Yuanhan Liu Sent: Monday, November 09, 2015 12:23 PM To: Chi, Xiaobo (Nokia - CN/Hangzhou) Cc: dev@dpdk.org; changchun.ouyang@intel.com Subject: Re: [dpdk-dev] [PATCH] vhost: eventfd_link's minor number shall be= specified On Fri, Nov 06, 2015 at 02:04:37PM +0800, Xiaobo Chi wrote: > eventfd_link_misc's minor number shall be MISC_DYNAMIC_MINOR to let Linu= x kernel dynamically assign one while loading. For such (fix) patch, I'd like to see what exact issue your patch fixes. And if it fixes an issue, you'd better title your patch with something like "vhost: fix ...", so that it's likely Thomas will put it into high priority. --yliu >=20 > Signed-off-by: Xiaobo Chi > --- > lib/librte_vhost/eventfd_link/eventfd_link.c | 1 + > 1 file changed, 1 insertion(+) >=20 > diff --git a/lib/librte_vhost/eventfd_link/eventfd_link.c b/lib/librte_vh= ost/eventfd_link/eventfd_link.c > index c54a938..4b05b5a 100644 > --- a/lib/librte_vhost/eventfd_link/eventfd_link.c > +++ b/lib/librte_vhost/eventfd_link/eventfd_link.c > @@ -249,6 +249,7 @@ static const struct file_operations eventfd_link_fops= =3D { > =20 > =20 > static struct miscdevice eventfd_link_misc =3D { > + .minor =3D MISC_DYNAMIC_MINOR, > .name =3D "eventfd-link", > .fops =3D &eventfd_link_fops, > }; > --=20 > 1.9.4.msysgit.2