Re: [PATCH] migration/rdma: prevent from double free the same mr

[Dr. David Alan Gilbert]

* Li Zhijian (lizhijian@cn.fujitsu.com) wrote:
> backtrace:
> '0x00007ffff5f44ec2 in __ibv_dereg_mr_1_1 (mr=0x7fff1007d390) at 
> /home/lizhijian/rdma-core/libibverbs/verbs.c:478
> 478             void *addr              = mr->addr;

ANy idea why it deletes the same mr twice?
What was your commandline?

Dave

> (gdb) bt
>  #0  0x00007ffff5f44ec2 in __ibv_dereg_mr_1_1 (mr=0x7fff1007d390) at 
> /home/lizhijian/rdma-core/libibverbs/verbs.c:478
>  #1  0x0000555555891fcc in rdma_delete_block (block=<optimized out>, 
> rdma=0x7fff38176010) at ../migration/rdma.c:691
>  #2  qemu_rdma_cleanup (rdma=0x7fff38176010) at ../migration/rdma.c:2365
>  #3  0x00005555558925b0 in qio_channel_rdma_close_rcu (rcu=0x555556b8b6c0) at 
> ../migration/rdma.c:3073
>  #4  0x0000555555d652a3 in call_rcu_thread (opaque=opaque@entry=0x0) at 
> ../util/rcu.c:281
>  #5  0x0000555555d5edf9 in qemu_thread_start (args=0x7fffe88bb4d0) at 
> ../util/qemu-thread-posix.c:541
>  #6  0x00007ffff54c73f9 in start_thread () at /lib64/libpthread.so.0
>  #7  0x00007ffff53f3b03 in clone () at /lib64/libc.so.6 '
> 
> Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
> ---
>  migration/rdma.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/migration/rdma.c b/migration/rdma.c
> index b6cc4bef4a8..0f22b8227c0 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -1143,6 +1143,7 @@ static int qemu_rdma_reg_whole_ram_blocks(RDMAContext 
> *rdma)
>  
>      for (i--; i >= 0; i--) {
>          ibv_dereg_mr(local->block[i].mr);
> +        local->block[i].mr = NULL;
>          rdma->total_registrations--;
>      }
>  
> -- 
> 2.30.2
> 
> 
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK