linux_dsm_epyc7002/net/core
Julian Wiedmann 7c4046b1c5 Revert "net: sched: make newly activated qdiscs visible"
This reverts commit 4cda75275f
from net-next.

Brown bag time.

Michal noticed that this change doesn't work at all when
netif_set_real_num_tx_queues() gets called prior to an initial
dev_activate(), as for instance igb does.

Doing so dies with:

[   40.579142] BUG: kernel NULL pointer dereference, address: 0000000000000400
[   40.586922] #PF: supervisor read access in kernel mode
[   40.592668] #PF: error_code(0x0000) - not-present page
[   40.598405] PGD 0 P4D 0
[   40.601234] Oops: 0000 [#1] PREEMPT SMP PTI
[   40.605909] CPU: 18 PID: 1681 Comm: wickedd Tainted: G            E     5.6.0-rc3-ethnl.50-default #1
[   40.616205] Hardware name: Intel Corporation S2600CP/S2600CP, BIOS RMLSDP.86I.R3.27.D685.1305151734 05/15/2013
[   40.627377] RIP: 0010:qdisc_hash_add.part.22+0x2e/0x90
[   40.633115] Code: 00 55 53 89 f5 48 89 fb e8 2f 9b fb ff 85 c0 74 44 48 8b 43 40 48 8b 08 69 43 38 47 86 c8 61 c1 e8 1c 48 83 e8 80 48 8d 14 c1 <48> 8b 04 c1 48 8d 4b 28 48 89 53 30 48 89 43 28 48 85 c0 48 89 0a
[   40.654080] RSP: 0018:ffffb879864934d8 EFLAGS: 00010203
[   40.659914] RAX: 0000000000000080 RBX: ffffffffb8328d80 RCX: 0000000000000000
[   40.667882] RDX: 0000000000000400 RSI: 0000000000000000 RDI: ffffffffb831faa0
[   40.675849] RBP: 0000000000000000 R08: ffffa0752c8b9088 R09: ffffa0752c8b9208
[   40.683816] R10: 0000000000000006 R11: 0000000000000000 R12: ffffa0752d734000
[   40.691783] R13: 0000000000000008 R14: 0000000000000000 R15: ffffa07113c18000
[   40.699750] FS:  00007f94548e5880(0000) GS:ffffa0752e980000(0000) knlGS:0000000000000000
[   40.708782] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   40.715189] CR2: 0000000000000400 CR3: 000000082b6ae006 CR4: 00000000001606e0
[   40.723156] Call Trace:
[   40.725888]  dev_qdisc_set_real_num_tx_queues+0x61/0x90
[   40.731725]  netif_set_real_num_tx_queues+0x94/0x1d0
[   40.737286]  __igb_open+0x19a/0x5d0 [igb]
[   40.741767]  __dev_open+0xbb/0x150
[   40.745567]  __dev_change_flags+0x157/0x1a0
[   40.750240]  dev_change_flags+0x23/0x60

[...]

Fixes: 4cda75275f ("net: sched: make newly activated qdiscs visible")
Reported-by: Michal Kubecek <mkubecek@suse.cz>
CC: Michal Kubecek <mkubecek@suse.cz>
CC: Eric Dumazet <edumazet@google.com>
CC: Jamal Hadi Salim <jhs@mojatatu.com>
CC: Cong Wang <xiyou.wangcong@gmail.com>
CC: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-12 11:19:24 -07:00
..
bpf_sk_storage.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-02-29 15:53:35 -08:00
datagram.c net: datagram: drop 'destructor' argument from several helpers 2020-02-28 12:12:53 -08:00
datagram.h
dev_addr_lists.c net: remove unnecessary variables and callback 2019-10-24 14:53:49 -07:00
dev_ioctl.c net: Introduce peer to peer one step PTP time stamping. 2019-12-25 19:51:34 -08:00
dev.c Revert "net: sched: make newly activated qdiscs visible" 2020-03-12 11:19:24 -07:00
devlink.c devlink: Introduce devlink port flavour virtual 2020-03-03 15:40:40 -08:00
drop_monitor.c net: core: Replace zero-length array with flexible-array member 2020-02-28 12:08:37 -08:00
dst_cache.c
dst.c net: print proper warning on dst underflow 2019-09-26 09:05:56 +02:00
failover.c
fib_notifier.c net: fib_notifier: propagate extack down to the notifier block callback 2019-10-04 11:10:56 -07:00
fib_rules.c net: fib_rules: Correctly set table field when table number exceeds 8 bits 2020-02-16 18:38:24 -08:00
filter.c net: Remove unneeded export of a couple of xdp generic functions 2020-02-24 11:03:38 -08:00
flow_dissector.c bpf: Use bpf_prog_run_pin_on_cpu() at simple call sites. 2020-02-24 16:20:09 -08:00
flow_offload.c flow_offload: pass action cookie through offload structures 2020-02-25 11:05:54 -08:00
gen_estimator.c net_sched: gen_estimator: extend packet counter to 64bit 2019-11-06 21:51:36 -08:00
gen_stats.c net_sched: add TCA_STATS_PKT64 attribute 2019-11-05 18:20:55 -08:00
gro_cells.c
hwbm.c net: hwbm: Make the hwbm_pool lock a mutex 2019-06-09 19:40:10 -07:00
link_watch.c net: link_watch: prevent starvation when processing linkwatch wq 2019-07-01 19:02:47 -07:00
lwt_bpf.c net: ipv6_stub: use ip6_dst_lookup_flow instead of ip6_dst_lookup 2019-12-04 12:27:13 -08:00
lwtunnel.c
Makefile ethtool: move to its own directory 2019-12-12 17:07:05 -08:00
neighbour.c net: neigh: remove unused NEIGH_SYSCTL_MS_JIFFIES_ENTRY 2020-02-20 10:02:23 -08:00
net_namespace.c netns: Constify exported functions 2020-01-17 13:25:24 +01:00
net-procfs.c net: procfs: use index hashlist instead of name hashlist 2019-10-01 14:47:19 -07:00
net-sysfs.c net-sysfs: add queue_change_owner() 2020-02-26 20:07:26 -08:00
net-sysfs.h net-sysfs: add netdev_change_owner() 2020-02-26 20:07:25 -08:00
net-traces.c page_pool: add tracepoints for page_pool with details need by XDP 2019-06-19 11:23:13 -04:00
netclassid_cgroup.c
netevent.c
netpoll.c net: fix skb use after free in netpoll 2019-08-27 20:52:02 -07:00
netprio_cgroup.c netprio: use css ID instead of cgroup ID 2019-11-12 08:18:03 -08:00
page_pool.c net: page_pool: API cleanup and comments 2020-02-20 10:09:25 -08:00
pktgen.c pktgen: Allow on loopback device 2020-03-10 15:44:59 -07:00
ptp_classifier.c
request_sock.c tcp: add rcu protection around tp->fastopen_rsk 2019-10-13 10:13:08 -07:00
rtnetlink.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-02-21 13:39:34 -08:00
scm.c y2038: socket: remove timespec reference in timestamping 2019-11-15 14:38:29 +01:00
secure_seq.c
skbuff.c net: core: Distribute switch variables for initialization 2020-02-20 10:00:19 -08:00
skmsg.c bpf: Use bpf_prog_run_pin_on_cpu() at simple call sites. 2020-02-24 16:20:09 -08:00
sock_diag.c sock: make cookie generation global instead of per netns 2019-08-09 13:14:46 -07:00
sock_map.c bpf, sockmap: Let all kernel-land lookup values in SOCKMAP/SOCKHASH 2020-02-21 22:29:45 +01:00
sock_reuseport.c net: Generate reuseport group ID on group creation 2020-02-21 22:29:45 +01:00
sock.c net, sk_msg: Clear sk_user_data pointer on clone if tagged 2020-02-21 22:29:45 +01:00
stream.c tcp: make sure EPOLLOUT wont be missed 2019-08-19 13:07:43 -07:00
sysctl_net_core.c net, sysctl: Fix compiler warning when only cBPF is present 2019-12-19 17:17:51 +01:00
timestamping.c net: Introduce a new MII time stamping interface. 2019-12-25 19:51:33 -08:00
tso.c net: Use skb accessors in network core 2019-07-22 20:47:56 -07:00
utils.c net: Fix skb->csum update in inet_proto_csum_replace16(). 2020-01-24 20:54:30 +01:00
xdp.c net: page_pool: API cleanup and comments 2020-02-20 10:09:25 -08:00