diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 434e3ece6688ef..6d0c95638e1bf9 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -1053,9 +1053,15 @@ static unsigned long get_entry_ip(unsigned long fentry_ip) { u32 instr; - /* Being extra safe in here in case entry ip is on the page-edge. */ - if (get_kernel_nofault(instr, (u32 *) fentry_ip - 1)) - return fentry_ip; + /* We want to be extra safe in case entry ip is on the page edge, + * but otherwise we need to avoid get_kernel_nofault()'s overhead. + */ + if ((fentry_ip & ~PAGE_MASK) < ENDBR_INSN_SIZE) { + if (get_kernel_nofault(instr, (u32 *)(fentry_ip - ENDBR_INSN_SIZE))) + return fentry_ip; + } else { + instr = *(u32 *)(fentry_ip - ENDBR_INSN_SIZE); + } if (is_endbr(instr)) fentry_ip -= ENDBR_INSN_SIZE; return fentry_ip;