Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1356155 > unrolled thread

Re: Glibc recvmsg from kernel netlink socket hangs forever

Back to article view | Back to linux.kernel

Contents

  Re: Glibc recvmsg from kernel netlink socket hangs forever Jun Wang <junwang123@gmail.com> - 2016-03-11 20:40 +0100
    Re: Glibc recvmsg from kernel netlink socket hangs forever Guenter Roeck <linux@roeck-us.net> - 2016-03-12 01:00 +0100
      Re: Glibc recvmsg from kernel netlink socket hangs forever Cong Wang <xiyou.wangcong@gmail.com> - 2016-03-12 01:20 +0100
        Re: Glibc recvmsg from kernel netlink socket hangs forever Guenter Roeck <linux@roeck-us.net> - 2016-03-12 02:30 +0100

#1356155 — Re: Glibc recvmsg from kernel netlink socket hangs forever

> On 09/25/2015 08:55 AM, Herbert Xu wrote:
>> On Thu, Sep 24, 2015 at 10:34:10PM -0700, Guenter Roeck wrote:
>>>
>>> Any idea what may be needed for 4.1 ?
>>> I am currently trying https://patchwork.ozlabs.org/patch/473041/,
>>
>> This patch should not make any difference on 4.1 and later because
>> 4.1 is where I rewrote rhashtable resizing and it should work (or
>> if it is broken then the latest kernel should be broken too).
>>
> Yes, applying (only) the above patch to 4.1 didn't help.
>
>>> but I have no idea if that will help with the problem we are seeing there.
>>
>> Having looked at your message agin I don't think the issue I
>> alluded to is relevant since the symptom there ought to be a
>> straight kernel lock-up as opposed to just a user-space one because
>> you will end up with the kernel sending a message to itself.
>>
>> And the fact that 4.2 works is more indicative as the bug is
>> present in both 4.1 and 4.2.
>>
>> I'll try to reproduce this in 4.1 as time permits but no promises.
>>
>
> I applied your patches (and a few additional netlink changes from 4.2)
> to our 4.1 branch. I'll let you know if it makes a difference for us.
>
> Thanks,
> Guenter

Guenter,

Which additional netlink changes from 4.2 did you patch? We still see
the problem with your test program with 4.1.12 which have the
following two patches mentioned by Herbert Xu on this thread.


> https://patchwork.ozlabs.org/patch/519245/
> https://patchwork.ozlabs.org/patch/520824/

Thanks,
Jun

[toc] | [next] | [standalone]

#1356292

On Fri, Mar 11, 2016 at 11:33:17AM -0800, Jun Wang wrote:
> > On 09/25/2015 08:55 AM, Herbert Xu wrote:
> >> On Thu, Sep 24, 2015 at 10:34:10PM -0700, Guenter Roeck wrote:
> >>>
> >>> Any idea what may be needed for 4.1 ?
> >>> I am currently trying https://patchwork.ozlabs.org/patch/473041/,
> >>
> >> This patch should not make any difference on 4.1 and later because
> >> 4.1 is where I rewrote rhashtable resizing and it should work (or
> >> if it is broken then the latest kernel should be broken too).
> >>
> > Yes, applying (only) the above patch to 4.1 didn't help.
> >
> >>> but I have no idea if that will help with the problem we are seeing there.
> >>
> >> Having looked at your message agin I don't think the issue I
> >> alluded to is relevant since the symptom there ought to be a
> >> straight kernel lock-up as opposed to just a user-space one because
> >> you will end up with the kernel sending a message to itself.
> >>
> >> And the fact that 4.2 works is more indicative as the bug is
> >> present in both 4.1 and 4.2.
> >>
> >> I'll try to reproduce this in 4.1 as time permits but no promises.
> >>
> >
> > I applied your patches (and a few additional netlink changes from 4.2)
> > to our 4.1 branch. I'll let you know if it makes a difference for us.
> >
> > Thanks,
> > Guenter
> 
> Guenter,
> 
> Which additional netlink changes from 4.2 did you patch? We still see
> the problem with your test program with 4.1.12 which have the
> following two patches mentioned by Herbert Xu on this thread.
> 
Jun,

Sorry, I don't recall, and I no longer have access to the kernel since
I now work for a different company. I do recall that we had to apply
additional patches later, but I don't remember details.

Guenter

[toc] | [prev] | [next] | [standalone]

#1356298

On Fri, Mar 11, 2016 at 3:50 PM, Guenter Roeck <linux@roeck-us.net> wrote:
> On Fri, Mar 11, 2016 at 11:33:17AM -0800, Jun Wang wrote:
>> Guenter,
>>
>> Which additional netlink changes from 4.2 did you patch? We still see
>> the problem with your test program with 4.1.12 which have the
>> following two patches mentioned by Herbert Xu on this thread.
>>
> Jun,
>
> Sorry, I don't recall, and I no longer have access to the kernel since
> I now work for a different company. I do recall that we had to apply
> additional patches later, but I don't remember details.

I think it is probably this one:

https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/net/netlink/af_netlink.c?h=linux-4.1.y&id=a52ec6de6d1638e8c203d7188c55627f75371612

The original backport is incorrect in 4.1 branch, and it is fixed now.

[toc] | [prev] | [next] | [standalone]

#1356308

On 03/11/2016 04:13 PM, Cong Wang wrote:
> On Fri, Mar 11, 2016 at 3:50 PM, Guenter Roeck <linux@roeck-us.net> wrote:
>> On Fri, Mar 11, 2016 at 11:33:17AM -0800, Jun Wang wrote:
>>> Guenter,
>>>
>>> Which additional netlink changes from 4.2 did you patch? We still see
>>> the problem with your test program with 4.1.12 which have the
>>> following two patches mentioned by Herbert Xu on this thread.
>>>
>> Jun,
>>
>> Sorry, I don't recall, and I no longer have access to the kernel since
>> I now work for a different company. I do recall that we had to apply
>> additional patches later, but I don't remember details.
>
> I think it is probably this one:
>
> https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/net/netlink/af_netlink.c?h=linux-4.1.y&id=a52ec6de6d1638e8c203d7188c55627f75371612
>
> The original backport is incorrect in 4.1 branch, and it is fixed now.
>
Yes, overall I would hope that 4.1.y should be up to date and working now.

Guenter

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web