Sometimes it happens that KConfig dependencies are not handled like in the following scenario: - config A bool - config B bool depends on A -config C bool select B If one selects C, then it will select B without checking its dependency to A, if A hasn't been selected elsewhere, it will result in a build crash. This is what happens on the following build error: kernel/built-in.o: In function `marker_update_probe_range': (.text+0x52f64): undefined reference to `tracepoint_probe_register_noupdate' kernel/built-in.o: In function `marker_update_probe_range': (.text+0x52f74): undefined reference to `tracepoint_probe_unregister_noupdate' kernel/built-in.o: In function `marker_update_probe_range': (.text+0x52fb9): undefined reference to `tracepoint_probe_unregister_noupdate' kernel/built-in.o: In function `marker_update_probes': marker.c:(.text+0x530ba): undefined reference to `tracepoint_probe_update_all' CONFIG_KVM_TRACE will select CONFIG_MARKER, but the latter depends on CONFIG_TRACEPOINTS which will not be selected. A temporary fix is to make CONFIG_MARKER select CONFIG_TRACEPOINTS, though it doesn't fix the source KConfig dependency handling problem. Reported-by: Ingo Molnar <mingo@xxxxxxx> Cc: Roman Zippel <zippel@xxxxxxxxxxxxxx> Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx> --- init/Kconfig | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/init/Kconfig b/init/Kconfig index b6400a5..a93f957 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -975,7 +975,7 @@ config TRACEPOINTS config MARKERS bool "Activate markers" - depends on TRACEPOINTS + select TRACEPOINTS help Place an empty function call at each marker site. Can be dynamically changed for a probe function. -- 1.6.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
