6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Masahiro Yamada <masahiroy@xxxxxxxxxx>
[ Upstream commit 712aba5543b88996bc4682086471076fbf048927 ]
As commit afa974b77128 ("kbuild: add real-prereqs shorthand for
$(filter-out FORCE,$^)") explained, $(real-prereqs) is not just a list
of objects when linking a multi-object module. If a single-object module
is turned into a multi-object module, $^ (and therefore $(real-prereqs)
as well) contains header files recorded in the *.cmd file. Such headers
must be filtered out.
Now that a DTB can be built either from a single source or multiple
source files, the same issue can occur.
Consider the following scenario:
First, foo.dtb is implemented as a single-blob device tree.
The code looks something like this:
[Sample Code 1]
Makefile:
dtb-y += foo.dtb
foo.dts:
#include <dt-bindings/gpio/gpio.h>
/dts-v1/;
/ { };
When it is compiled, .foo.dtb.cmd records that foo.dtb depends on
scripts/dtc/include-prefixes/dt-bindings/gpio/gpio.h.
Later, foo.dtb is split into a base and an overlay. The code looks
something like this:
[Sample Code 2]
Makefile:
dtb-y += foo.dtb
foo-dtbs := foo-base.dtb foo-addon.dtbo
foo-base.dts:
#include <dt-bindings/gpio/gpio.h>
/dts-v1/;
/ { };
foo-addon.dtso:
/dts-v1/;
/plugin/;
/ { };
If you rebuild foo.dtb without 'make clean', you will get this error:
Overlay 'scripts/dtc/include-prefixes/dt-bindings/gpio/gpio.h' is incomplete
$(real-prereqs) contains not only foo-base.dtb and foo-addon.dtbo but
also scripts/dtc/include-prefixes/dt-bindings/gpio/gpio.h, which is
passed to scripts/dtc/fdtoverlay.
Fixes: 15d16d6dadf6 ("kbuild: Add generic rule to apply fdtoverlay")
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
scripts/Makefile.lib | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 68d0134bdbf9d..e702552fb131a 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -395,8 +395,12 @@ cmd_dtc = $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ;
-d $(depfile).dtc.tmp $(dtc-tmp) ; \
cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)
+# NOTE:
+# Do not replace $(filter %.dtb %.dtbo, $^) with $(real-prereqs). When a single
+# DTB is turned into a multi-blob DTB, $^ will contain header file dependencies
+# recorded in the .*.cmd file.
quiet_cmd_fdtoverlay = DTOVL $@
- cmd_fdtoverlay = $(objtree)/scripts/dtc/fdtoverlay -o $@ -i $(real-prereqs)
+ cmd_fdtoverlay = $(objtree)/scripts/dtc/fdtoverlay -o $@ -i $(filter %.dtb %.dtbo, $^)
$(multi-dtb-y): FORCE
$(call if_changed,fdtoverlay)
--
2.43.0
