openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

bpf: Allow usage of BPF ringbuffer in sleepable programs 

The BPF ringbuffer map is pre-allocated and the implementation logic
does not rely on disabling preemption or per-cpu data structures. Using
the BPF ringbuffer sleepable LSM and tracing programs does not trigger
any warnings with DEBUG_ATOMIC_SLEEP, DEBUG_PREEMPT,
PROVE_RCU and PROVE_LOCKING and LOCKDEP enabled.

This allows helpers like bpf_copy_from_user and bpf_ima_inode_hash to
write to the BPF ring buffer from sleepable BPF programs.

Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210204193622.3367275-2-kpsingh@kernel.org
This commit is contained in:
KP Singh 2021-02-04 19:36:21 +00:00 committed by Andrii Nakryiko
parent ec45c5faa2
commit ba90c2cc02
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
kernel/bpf/verifier.c
View File

@ -10024,9 +10024,11 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env,
return -EINVAL; return -EINVAL;
} }
break; break;
case BPF_MAP_TYPE_RINGBUF:
break;
default: default:
verbose(env, verbose(env,
"Sleepable programs can only use array and hash maps\n"); "Sleepable programs can only use array, hash, and ringbuf maps\n");
return -EINVAL; return -EINVAL;
} }