[PATCH] MIPS: boot: compressed: fix the vmlinuz link with ld.lld

[PATCH] MIPS: boot: compressed: fix the vmlinuz link with ld.lld

[Rosen Penev]

ld.lld cannot link a 32-bit executable at a sign-extended address. With
a sign-extended ZBOOT_LOAD_ADDRESS, such as the BCM47XX default of
0xffffffff80400000, the vmlinuz link fails:

  ld.lld: error: section .text at 0xffffffff80400000 of size 0x35a4
  exceeds available address space

arch/mips/Makefile already avoids this for vmlinux by linking at
LINKER_LOAD_ADDRESS, which drops the upper 32 bits on 32-bit kernels.
Do the same for vmlinuz. The address computed by calc_vmlinuz_load_addr
is already derived from LINKER_LOAD_ADDRESS, which is why only an
explicit ZBOOT_LOAD_ADDRESS is affected.

Assisted-by: LLM
Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 arch/mips/boot/compressed/Makefile | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile
index e0b8ec9a9516..ee554eaaa18f 100644
--- a/arch/mips/boot/compressed/Makefile
+++ b/arch/mips/boot/compressed/Makefile
@@ -96,12 +96,20 @@ VMLINUZ_LOAD_ADDRESS = $(shell $(obj)/calc_vmlinuz_load_addr \
 endif
 UIMAGE_LOADADDR = $(VMLINUZ_LOAD_ADDRESS)
 
+# Like LINKER_LOAD_ADDRESS in arch/mips/Makefile: ld.lld cannot link a
+# 32-bit executable at a sign-extended address, so drop the upper 32 bits.
+ifdef CONFIG_64BIT
+VMLINUZ_LINK_ADDRESS = $(VMLINUZ_LOAD_ADDRESS)
+else
+VMLINUZ_LINK_ADDRESS = $(subst 0xffffffff,0x,$(VMLINUZ_LOAD_ADDRESS))
+endif
+
 vmlinuzobjs-y += $(obj)/piggy.o
 
 targets += ../../../../vmlinuz
 
 quiet_cmd_zld = LD      $@
-      cmd_zld = $(LD) $(KBUILD_LDFLAGS) -Ttext $(VMLINUZ_LOAD_ADDRESS) -T $< $(vmlinuzobjs-y) -o $@
+      cmd_zld = $(LD) $(KBUILD_LDFLAGS) -Ttext $(VMLINUZ_LINK_ADDRESS) -T $< $(vmlinuzobjs-y) -o $@
 quiet_cmd_strip = STRIP   $@
       cmd_strip = $(STRIP) -s $@
 
-- 
2.56.0