[ovs-discuss] fix coredump in ofproto_destroy__

[Ben Pfaff]

On Tue, Aug 14, 2018 at 04:08:27AM +0000, liucheng (J) wrote:
> Hi,all:
> Threr is a coredump when I add and delete bridges. When the rcu thread call ofproto_destroy__, the main thread may call ofproto_create. But the ofproto_destroy__ fun doesn't have the ofproto_mutex when access the all_ofprotos.
> 
> The statack is under below:
> 
> #0  0x00007f824aa0d197 in raise () from /usr/lib64/libc.so.6
> Missing separate debuginfos, use: debuginfo-install dpdk-mlx4-pmd-16.11-R5.RC6.003.x86_64 glibc-2.17-157.h13.x86_64 keyutils-libs-1.5.8-3.x86_64 krb5-libs-1.13.2-12.h2.x86_64 libcom_err-1.42.9-9.h1.x86_64 libgcc-4.8.3-10.h2.x86_64 libibverbs-1.2.1mlnx1-OFED.4.0.1.5.3.40200.x86_64 libnl-1.1.4-3.x86_64 libselinux-2.2.2-6.x86_64 numactl-libs-2.0.9-4.x86_64 openssl-libs-1.0.1e-60.1.h2.x86_64 pcre-8.32-15.1.h2.x86_64 uvpkmc-1.0.0-725.x86_64 xz-libs-5.1.2-9alpha.x86_64 zlib-1.2.7-14.x86_64
> (gdb) bt
> #0  0x00007f824aa0d197 in raise () from /usr/lib64/libc.so.6
> #1  0x00007f824aa0e888 in abort () from /usr/lib64/libc.so.6
> #2  0x0000000000658249 in PAT_abort ()
> #3  0x000000000065538d in patchIllInsHandler ()
> #4  <signal handler called>
> #5  0x0000000000478a5b in hmap_remove (node=0x3320150, hmap=0x95fc40 <all_ofprotos>) at include/openvswitch/hmap.h:287
> #6  ofproto_destroy__ (ofproto=0x3320150) at ofproto/ofproto.c:1642
> #7  0x0000000000535e46 in ovsrcu_call_postponed () at lib/ovs_rcu.c:323
> #8  0x0000000000536014 in ovsrcu_postpone_thread (arg=<optimized out>) at lib/ovs_rcu.c:338
> #9  0x0000000000538488 in ovsthread_wrapper (aux_=<optimized out>) at lib/ovs_thread.c:682
> #10 0x00007f824c130dc5 in start_thread () from /usr/lib64/libpthread.so.0
> #11 0x00007f824aacf7bd in clone () from /usr/lib64/libc.so.6
> 
> 
> Here is the fix patch:

Thanks.  May I have a Signed-off-by for this?

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