From: Alexei Starovoitov <ast@kernel.org> mainline inclusion from mainline-5.12-rc1 commit 031d6e02ddbb8dea747c1abb697d556901f07dd4 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5EUVD CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... ------------------------------------------------- In older non-RT kernels migrate_disable() was the same as preempt_disable(). Since commit 74d862b682f5 ("sched: Make migrate_disable/enable() independent of RT") migrate_disable() is real and doesn't prevent sleeping. Running sleepable programs with migration disabled allows to add support for program stats and per-cpu maps later. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: KP Singh <kpsingh@kernel.org> Link: https://lore.kernel.org/bpf/20210210033634.62081-3-alexei.starovoitov@gmail.... (cherry picked from commit 031d6e02ddbb8dea747c1abb697d556901f07dd4) Signed-off-by: Wang Yufen <wangyufen@huawei.com> --- kernel/bpf/trampoline.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index 9bd1731eea0d..e9cc7ac3856f 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -534,11 +534,13 @@ void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start) void notrace __bpf_prog_enter_sleepable(void) { rcu_read_lock_trace(); + migrate_disable(); might_fault(); } void notrace __bpf_prog_exit_sleepable(void) { + migrate_enable(); rcu_read_unlock_trace(); } -- 2.20.1