From 852d4dbd70baa550cc5e8ef789aa719d30e94242 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Sun, 15 Jan 2023 14:15:51 -0700 Subject: [PATCH] trace: Detect an infinite loop If something is wrong with a board's timer function such that it calls functions not marked with notrace, U-Boot will hang. Detect this, print a message and disable the trace. Signed-off-by: Simon Glass --- lib/trace.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/lib/trace.c b/lib/trace.c index bbc316a..1091a57 100644 --- a/lib/trace.c +++ b/lib/trace.c @@ -39,6 +39,7 @@ struct trace_hdr { int depth_limit; /* Depth limit to trace to */ int max_depth; /* Maximum depth seen so far */ int min_depth; /* Minimum depth seen so far */ + bool trace_locked; /* Used to detect recursive tracing */ }; /* Pointer to start of trace buffer */ @@ -133,6 +134,14 @@ void notrace __cyg_profile_func_enter(void *func_ptr, void *caller) if (trace_enabled) { int func; + if (hdr->trace_locked) { + trace_enabled = 0; + puts("trace: recursion detected, disabling\n"); + hdr->trace_locked = false; + return; + } + + hdr->trace_locked = true; trace_swap_gd(); add_ftrace(func_ptr, caller, FUNCF_ENTRY); func = func_ptr_to_num(func_ptr); @@ -146,6 +155,7 @@ void notrace __cyg_profile_func_enter(void *func_ptr, void *caller) if (hdr->depth > hdr->max_depth) hdr->max_depth = hdr->depth; trace_swap_gd(); + hdr->trace_locked = false; } } -- 2.7.4