diff options
| author | Eric Dumazet <edumazet@google.com> | 2017-10-08 21:07:18 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-10-08 21:09:00 -0700 |
| commit | 951f788a80ff8b6339c5c1ab888b0d4b4352efd8 (patch) | |
| tree | 2eef7bace5149d10b68a5e09cdcea38ba37acd35 /fs/nfs/nfs4idmap.h | |
| parent | 51a0c00c6bf2156099f80c6892fd409a5d217b96 (diff) | |
ipv6: fix a BUG in rt6_get_pcpu_route()
Ido reported following splat and provided a patch.
[ 122.221814] BUG: using smp_processor_id() in preemptible [00000000] code: sshd/2672
[ 122.221845] caller is debug_smp_processor_id+0x17/0x20
[ 122.221866] CPU: 0 PID: 2672 Comm: sshd Not tainted 4.14.0-rc3-idosch-next-custom #639
[ 122.221880] Hardware name: Mellanox Technologies Ltd. MSN2100-CB2FO/SA001017, BIOS 5.6.5 06/07/2016
[ 122.221893] Call Trace:
[ 122.221919] dump_stack+0xb1/0x10c
[ 122.221946] ? _atomic_dec_and_lock+0x124/0x124
[ 122.221974] ? ___ratelimit+0xfe/0x240
[ 122.222020] check_preemption_disabled+0x173/0x1b0
[ 122.222060] debug_smp_processor_id+0x17/0x20
[ 122.222083] ip6_pol_route+0x1482/0x24a0
...
I believe we can simplify this code path a bit, since we no longer
hold a read_lock and need to release it to avoid a dead lock.
By disabling BH, we make sure we'll prevent code re-entry and
rt6_get_pcpu_route()/rt6_make_pcpu_route() run on the same cpu.
Fixes: 66f5d6ce53e6 ("ipv6: replace rwlock with rcu and spinlock in fib6_table")
Reported-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'fs/nfs/nfs4idmap.h')
0 files changed, 0 insertions, 0 deletions