6.6-stable review patch. If anyone has any objections, please let me know.
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From: Masahiro Yamada masahiroy@kernel.org
[ 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@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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)