Lorenzo Bianconi c576b9c77b bpf: cpumap: Fix possible rcpu kthread hung ... Fix the following cpumap kthread hung. The issue is currently occurring when __cpu_map_load_bpf_program fails (e.g if the bpf prog has not BPF_XDP_CPUMAP as expected_attach_type) $./test_progs -n 101 101/1 cpumap_with_progs:OK 101 xdp_cpumap_attach:OK Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED [ 369.996478] INFO: task cpumap/0/map:7:205 blocked for more than 122 seconds. [ 369.998463] Not tainted 5.8.0-rc4-01472-ge57892f50a07 #212 [ 370.000102] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 370.001918] cpumap/0/map:7 D 0 205 2 0x00004000 [ 370.003228] Call Trace: [ 370.003930] __schedule+0x5c7/0xf50 [ 370.004901] ? io_schedule_timeout+0xb0/0xb0 [ 370.005934] ? static_obj+0x31/0x80 [ 370.006788] ? mark_held_locks+0x24/0x90 [ 370.007752] ? cpu_map_bpf_prog_run_xdp+0x6c0/0x6c0 [ 370.008930] schedule+0x6f/0x160 [ 370.009728] schedule_preempt_disabled+0x14/0x20 [ 370.010829] kthread+0x17b/0x240 [ 370.011433] ? kthread_create_worker_on_cpu+0xd0/0xd0 [ 370.011944] ret_from_fork+0x1f/0x30 [ 370.012348] Showing all locks held in the system: [ 370.013025] 1 lock held by khungtaskd/33: [ 370.013432] #0: ffffffff82b24720 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x28/0x1c3 [ 370.014461] ============================================= Fixes: 9216477449 ("bpf: cpumap: Add the possibility to attach an eBPF program to cpumap") Reported-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Jakub Sitnicki <jakub@cloudflare.com> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/e54f2aabf959f298939e5507b09c48f8c2e380be.1595170625.git.lorenzo@kernel.org		2020-07-21 09:15:28 -07:00
..
arraymap.c	bpf: Remove redundant synchronize_rcu.	2020-07-01 08:07:13 -07:00
bpf_iter.c	bpf: Enable bpf_iter targets registering ctx argument types	2020-05-13 12:30:50 -07:00
bpf_lru_list.c
bpf_lru_list.h	bpf: Fix a typo "inacitve" -> "inactive"	2020-04-06 21:54:10 +02:00
bpf_lsm.c	bpf: Use tracing helpers for lsm programs	2020-06-01 15:08:04 -07:00
bpf_struct_ops_types.h	bpf: tcp: Support tcp_congestion_ops in bpf	2020-01-09 08:46:18 -08:00
bpf_struct_ops.c	bpf: Set map_btf_{name, id} for all map types	2020-06-22 22:22:58 +02:00
btf.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next	2020-07-13 18:04:05 -07:00
cgroup.c	bpf: Don't return EINVAL from {get,set}sockopt when optlen > PAGE_SIZE	2020-06-17 10:54:05 -07:00
core.c	bpf, netns: Handle multiple link attachments	2020-07-17 20:18:16 -07:00
cpumap.c	bpf: cpumap: Fix possible rcpu kthread hung	2020-07-21 09:15:28 -07:00
devmap.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next	2020-07-04 17:48:34 -07:00
disasm.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295	2019-06-05 17:36:38 +02:00
disasm.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295	2019-06-05 17:36:38 +02:00
dispatcher.c	bpf: Remove bpf_image tree	2020-03-13 12:49:52 -07:00
hashtab.c	bpf: Remove redundant synchronize_rcu.	2020-07-01 08:07:13 -07:00
helpers.c	bpf: Implement BPF ring buffer and verifier support for it	2020-06-01 14:38:22 -07:00
inode.c	bpf: Create file bpf iterator	2020-05-09 17:05:26 -07:00
local_storage.c	bpf: Set map_btf_{name, id} for all map types	2020-06-22 22:22:58 +02:00
lpm_trie.c	bpf: Remove redundant synchronize_rcu.	2020-07-01 08:07:13 -07:00
Makefile	flow_dissector: Move out netns_bpf prog callbacks	2020-06-01 15:21:02 -07:00
map_in_map.c	bpf: Implement CAP_BPF	2020-05-15 17:29:41 +02:00
map_in_map.h
map_iter.c	bpf: Enable bpf_iter targets registering ctx argument types	2020-05-13 12:30:50 -07:00
net_namespace.c	bpf, netns: Fix build without CONFIG_INET	2020-07-21 09:12:34 -07:00
offload.c	bpf, offload: Replace bitwise AND by logical AND in bpf_prog_offload_info_fill	2020-02-17 16:53:49 +01:00
percpu_freelist.c	bpf: Dont iterate over possible CPUs with interrupts disabled	2020-02-24 16:18:20 -08:00
percpu_freelist.h
queue_stack_maps.c	bpf: Remove redundant synchronize_rcu.	2020-07-01 08:07:13 -07:00
reuseport_array.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2020-07-11 00:46:00 -07:00
ringbuf.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2020-07-11 00:46:00 -07:00
stackmap.c	bpf: Resolve BTF IDs in vmlinux image	2020-07-13 10:42:02 -07:00
syscall.c	bpf: Introduce SK_LOOKUP program type with a dedicated attach point	2020-07-17 20:18:16 -07:00
sysfs_btf.c	bpf: Support llvm-objcopy for vmlinux BTF	2020-03-19 12:32:38 +01:00
task_iter.c	bpf: Fix bpf_iter's task iterator logic	2020-05-14 18:37:32 -07:00
tnum.c	bpf: Verifier, do explicit ALU32 bounds tracking	2020-03-30 14:59:53 -07:00
trampoline.c	bpf: lsm: Implement attach, detach and execution	2020-03-30 01:34:00 +02:00
verifier.c	bpf: Introduce SK_LOOKUP program type with a dedicated attach point	2020-07-17 20:18:16 -07:00