There has a backport bug between v5.10.79 and v5.10.80 when run bpf selftest "test_sockmap" on 5.10 lts kernel

There has a backport bug between v5.10.79 and v5.10.80 when run bpf selftest "test_sockmap" on 5.10 lts kernel

[Lucien Wang]

Kernel version：16ad71c250c1 (HEAD -> linux-5.10.y, tag: v5.10.209,
origin/linux-5.10.y) Linux 5.10.209

Bug reproduced steps：
1.  cd (kernel source tree root)/tools/testing/selftests/bpf
2.  make test_sockmap ; make test_progs
3.  ./test_sockmap
# 1/ 6  sockmap::txmsg test passthrough:OK
# 2/ 6  sockmap::txmsg test redirect:OK
# 3/ 6  sockmap::txmsg test drop:OK
# 4/ 6  sockmap::txmsg test ingress redirect:OK

After "# 4/ 6  sockmap::txmsg test ingress redirect:OK" display from
terminal, the main process stucks and sends nothing.
4. In other terminal run " ps fax |grep sockmap " ,below is output
  13076 pts/0    S+     0:00  |           \_ ./test_sockmap
  13129 pts/0    S+     0:00  |               \_ ./test_sockmap
  13130 pts/0    Z+     0:00  |               \_ [test_sockmap] <defunct>
  13237 pts/1    S+     0:00              \_ grep --color=auto sockmap
Obversely, because of child process 13129 sleep, so the main process is stuck.

My research:
I use Bisection method to find the bug patch " c842a4c4ae7f bpf:
sockmap, strparser, and tls are reusing qdisc_skb_cb and colliding
"(on linux-5.10.y branch), it backport from v5.16-rc1 ,
It must due to merge high patches incompletely, Please take a few
moment for this.

Re: There has a backport bug between v5.10.79 and v5.10.80 when run bpf selftest "test_sockmap" on 5.10 lts kernel

[Greg KH]

On Fri, Feb 02, 2024 at 11:40:38AM +0800, Lucien Wang wrote:
> Kernel version：16ad71c250c1 (HEAD -> linux-5.10.y, tag: v5.10.209,
> origin/linux-5.10.y) Linux 5.10.209
> 
> Bug reproduced steps：
> 1.  cd (kernel source tree root)/tools/testing/selftests/bpf
> 2.  make test_sockmap ; make test_progs
> 3.  ./test_sockmap
> # 1/ 6  sockmap::txmsg test passthrough:OK
> # 2/ 6  sockmap::txmsg test redirect:OK
> # 3/ 6  sockmap::txmsg test drop:OK
> # 4/ 6  sockmap::txmsg test ingress redirect:OK
> 
> After "# 4/ 6  sockmap::txmsg test ingress redirect:OK" display from
> terminal, the main process stucks and sends nothing.
> 4. In other terminal run " ps fax |grep sockmap " ,below is output
>   13076 pts/0    S+     0:00  |           \_ ./test_sockmap
>   13129 pts/0    S+     0:00  |               \_ ./test_sockmap
>   13130 pts/0    Z+     0:00  |               \_ [test_sockmap] <defunct>
>   13237 pts/1    S+     0:00              \_ grep --color=auto sockmap
> Obversely, because of child process 13129 sleep, so the main process is stuck.
> 
> My research:
> I use Bisection method to find the bug patch " c842a4c4ae7f bpf:
> sockmap, strparser, and tls are reusing qdisc_skb_cb and colliding
> "(on linux-5.10.y branch), it backport from v5.16-rc1 ,
> It must due to merge high patches incompletely, Please take a few
> moment for this.

I do not understand, sorry, what exactly do you want us to do here?

confused,

greg k-h

Re: There has a backport bug between v5.10.79 and v5.10.80 when run bpf selftest "test_sockmap" on 5.10 lts kernel

[Lucien Wang]

There has a bug when I run bpf selftest "test_sockmap" on Linux
5.10.209, and I found it introduced by "c842a4c4ae7f bpf: sockmap,
strparser, and tls are reusing qdisc_skb_cb and colliding".

On Fri, Feb 2, 2024 at 11:03 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Fri, Feb 02, 2024 at 11:40:38AM +0800, Lucien Wang wrote:
> > Kernel version：16ad71c250c1 (HEAD -> linux-5.10.y, tag: v5.10.209,
> > origin/linux-5.10.y) Linux 5.10.209
> >
> > Bug reproduced steps：
> > 1.  cd (kernel source tree root)/tools/testing/selftests/bpf
> > 2.  make test_sockmap ; make test_progs
> > 3.  ./test_sockmap
> > # 1/ 6  sockmap::txmsg test passthrough:OK
> > # 2/ 6  sockmap::txmsg test redirect:OK
> > # 3/ 6  sockmap::txmsg test drop:OK
> > # 4/ 6  sockmap::txmsg test ingress redirect:OK
> >
> > After "# 4/ 6  sockmap::txmsg test ingress redirect:OK" display from
> > terminal, the main process stucks and sends nothing.
> > 4. In other terminal run " ps fax |grep sockmap " ,below is output
> >   13076 pts/0    S+     0:00  |           \_ ./test_sockmap
> >   13129 pts/0    S+     0:00  |               \_ ./test_sockmap
> >   13130 pts/0    Z+     0:00  |               \_ [test_sockmap] <defunct>
> >   13237 pts/1    S+     0:00              \_ grep --color=auto sockmap
> > Obversely, because of child process 13129 sleep, so the main process is stuck.
> >
> > My research:
> > I use Bisection method to find the bug patch " c842a4c4ae7f bpf:
> > sockmap, strparser, and tls are reusing qdisc_skb_cb and colliding
> > "(on linux-5.10.y branch), it backport from v5.16-rc1 ,
> > It must due to merge high patches incompletely, Please take a few
> > moment for this.
>
> I do not understand, sorry, what exactly do you want us to do here?
>
> confused,
>
> greg k-h