[openib-general] Re: core and ipoib questions and oops

[Michael S. Tsirkin]

Quoting Michael S. Tsirkin <mst at mellanox.co.il>:
> #ifconfig ib0 down
> 
> Unable to handle kernel NULL pointer dereference at 0000000000000388
> RIP:
> Code: 49 8b 7d 08 48 81 c7 b4 00 00 00 f3 a6 75 17 49 8b 45 70 8b
> RIP <ffffffff88045204>{:ib_ipoib:ipoib_mcast_join_finish+100} RSP
> <ffff81017348dc58>
> CR2: 0000000000000388

Here's a bit more objdump output, and a corrected analysis:

> Seems to oops at 0xda4 here:
> 0000000000000d40 <ipoib_mcast_join_finish>:
> ipoib_mcast_join_finish():

[...]

drivers/infiniband/ulp/ipoib/ipoib_multicast.c:223
     d9d:       48 89 ee                mov    %rbp,%rsi
drivers/infiniband/ulp/ipoib/ipoib_multicast.c:220
     da0:       48 89 47 38             mov    %rax,0x38(%rdi)
drivers/infiniband/ulp/ipoib/ipoib_multicast.c:223
     da4:       49 8b 7d 08             mov    0x8(%r13),%rdi
     da8:       48 81 c7 b4 00 00 00    add    $0xb4,%rdi
     daf:       f3 a6                   repz cmpsb %es:(%rdi),%ds:(%rsi)
     db1:       75 17                   jne    dca <ipoib_mcast_join_finish+0x8a>

and ipoib_multicast.c:223 is this line:
if (!memcmp(mcast->mcmember.mgid.raw, priv->dev->broadcast + 4,
                    sizeof (union ib_gid))) {

-- 
MST