[PATCH v3 1/2] trace: select TIMER_EARLY to avoid infinite recursion

Pragnesh Patel pragnesh.patel at sifive.com
Sun Jan 10 13:42:52 CET 2021


When tracing functions is enabled this adds calls to
__cyg_profile_func_enter() and __cyg_profile_func_exit() to the traced
functions.

__cyg_profile_func_enter() and __cyg_profile_func_exit() invoke
timer_get_us() to record the entry and exit time.

initr_dm() will make gd->dm_root = NULL and gd->timer = NULL, so
timer_get_us() -> get_ticks() -> dm_timer_init() will lead to an
indefinite recursion.

So select TIMER_EARLY when tracing got enabled.

Signed-off-by: Pragnesh Patel <pragnesh.patel at sifive.com>
Reviewed-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Rick Chen <rick at andestech.com>
---

Changes in v3:
- no change

Changes in v2:
- new patch

 lib/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/Kconfig b/lib/Kconfig
index 7673d2e4e0..671386963a 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -210,6 +210,7 @@ config BITREVERSE
 config TRACE
 	bool "Support for tracing of function calls and timing"
 	imply CMD_TRACE
+	select TIMER_EARLY
 	help
 	  Enables function tracing within U-Boot. This allows recording of call
 	  traces including timing information. The command can write data to
-- 
2.17.1



More information about the U-Boot mailing list