From 031d6e02ddbb8dea747c1abb697d556901f07dd4 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Tue, 9 Feb 2021 19:36:27 -0800 Subject: bpf: Run sleepable programs with migration disabled 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 Signed-off-by: Daniel Borkmann Acked-by: KP Singh Link: https://lore.kernel.org/bpf/20210210033634.62081-3-alexei.starovoitov@gmail.com --- kernel/bpf/trampoline.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel/bpf') diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index 5be3beeedd74..89fc849ba271 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -425,11 +425,13 @@ 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(); } -- cgit v1.2.3