From: Alexei Starovoitov <ast@kernel.org>
Date: Mon, 24 Feb 2020 11:27:15 -0800
Subject: bpf: disable preemption for bpf progs attached to uprobe
Patch-mainline: v5.7-rc1
Git-commit: 70ed0706a48e3da3eb4515214fef658ff1184b9f
References: bsc#1162702,bsc#1177028
trace_call_bpf() no longer disables preemption on its own.
All callers of this function has to do it explicitly.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Daniel Wagner <dwagner@suse.de>
Acked-by: Gary Lin <glin@suse.com>
---
kernel/trace/trace_uprobe.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -1125,8 +1125,15 @@ static void __uprobe_perf_func(struct tr
int size, esize;
int rctx;
- if (bpf_prog_array_valid(call) && !trace_call_bpf(call, regs))
- return;
+ if (bpf_prog_array_valid(call)) {
+ u32 ret;
+
+ preempt_disable();
+ ret = trace_call_bpf(call, regs);
+ preempt_enable();
+ if (!ret)
+ return;
+ }
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));