bpf: Revert bpf_overrid_function() helper changes.

NACK'd by x86 maintainer.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 35 deletions

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 1865b0d4cdeb..506efe6e8ed9 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -13,10 +13,6 @@
 #include <linux/filter.h>
 #include <linux/uaccess.h>
 #include <linux/ctype.h>
-#include <linux/kprobes.h>
-#include <asm/kprobes.h>
-
-#include "trace_probe.h"
 #include "trace.h"
 
 u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
@@ -80,29 +76,6 @@ unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
 }
 EXPORT_SYMBOL_GPL(trace_call_bpf);
 
-#ifdef CONFIG_BPF_KPROBE_OVERRIDE
-BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc)
-{
-	__this_cpu_write(bpf_kprobe_override, 1);
-	regs_set_return_value(regs, rc);
-	arch_ftrace_kprobe_override_function(regs);
-	return 0;
-}
-#else
-BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc)
-{
-	return -EINVAL;
-}
-#endif
-
-static const struct bpf_func_proto bpf_override_return_proto = {
-	.func		= bpf_override_return,
-	.gpl_only	= true,
-	.ret_type	= RET_INTEGER,
-	.arg1_type	= ARG_PTR_TO_CTX,
-	.arg2_type	= ARG_ANYTHING,
-};
-
 BPF_CALL_3(bpf_probe_read, void *, dst, u32, size, const void *, unsafe_ptr)
 {
 	int ret;
@@ -578,10 +551,6 @@ static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func
 		return &bpf_get_stackid_proto;
 	case BPF_FUNC_perf_event_read_value:
 		return &bpf_perf_event_read_value_proto;
-	case BPF_FUNC_override_return:
-		pr_warn_ratelimited("%s[%d] is installing a program with bpf_override_return helper that may cause unexpected behavior!",
-				    current->comm, task_pid_nr(current));
-		return &bpf_override_return_proto;
 	default:
 		return tracing_func_proto(func_id);
 	}
@@ -797,10 +766,6 @@ int perf_event_attach_bpf_prog(struct perf_event *event,
 	struct bpf_prog_array *new_array;
 	int ret = -EEXIST;
 
-	/* Kprobe override only works for ftrace based kprobes. */
-	if (prog->kprobe_override && !trace_kprobe_ftrace(event->tp_event))
-		return -EINVAL;
-
 	mutex_lock(&bpf_event_mutex);
 
 	if (event->prog)