Nathan Chancellor reports that the s390 vmlinux fails to link with
GNU ld < 2.36 since commit 99cb0d917ffa ("arch: fix broken BuildID
for arm64 and riscv").
It happens for defconfig, or more specifically for CONFIG_EXPOLINE=y.
$ s390x-linux-gnu-ld --version | head -n1
GNU ld (GNU Binutils for Debian) 2.35.2
$ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- allnoconfig
$ ./scripts/config -e CONFIG_EXPOLINE
$ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- olddefconfig
$ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu-
`.exit.text' referenced in section `.s390_return_reg' of drivers/base/dd.o: defined in discarded section `.exit.text' of drivers/base/dd.o
make[1]: *** [scripts/Makefile.vmlinux:34: vmlinux] Error 1
make: *** [Makefile:1252: vmlinux] Error 2
arch/s390/kernel/vmlinux.lds.S wants to keep EXIT_TEXT:
.exit.text : {
EXIT_TEXT
}
But, at the same time, EXIT_TEXT is thrown away by DISCARD because
s390 does not define RUNTIME_DISCARD_EXIT.
I still do not understand why the latter wins after 99cb0d917ffa,
but defining RUNTIME_DISCARD_EXIT seems correct because the comment
line in arch/s390/kernel/vmlinux.lds.S says:
/*
* .exit.text is discarded at runtime, not link time,
* to deal with references from __bug_table
*/
Nathan also found that binutils commit 21401fc7bf67 ("Duplicate output
sections in scripts") cured this issue, so we cannot reproduce it with
binutils 2.36+, but it is better to not rely on it.
Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv")
Link: https://lore.kernel.org/all/[email protected]/
Reported-by: Nathan Chancellor <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>
---
arch/s390/kernel/vmlinux.lds.S | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S
index 5ea3830af0cc..6e101e6f499d 100644
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -17,6 +17,8 @@
/* Handle ro_after_init data on our own. */
#define RO_AFTER_INIT_DATA
+#define RUNTIME_DISCARD_EXIT
+
#define EMITS_PT_NOTE
#include <asm-generic/vmlinux.lds.h>
--
2.34.1
On Thu, Jan 05, 2023 at 12:13:06PM +0900, Masahiro Yamada wrote:
> Nathan Chancellor reports that the s390 vmlinux fails to link with
> GNU ld < 2.36 since commit 99cb0d917ffa ("arch: fix broken BuildID
> for arm64 and riscv").
>
> It happens for defconfig, or more specifically for CONFIG_EXPOLINE=y.
>
> $ s390x-linux-gnu-ld --version | head -n1
> GNU ld (GNU Binutils for Debian) 2.35.2
> $ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- allnoconfig
> $ ./scripts/config -e CONFIG_EXPOLINE
> $ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- olddefconfig
> $ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu-
> `.exit.text' referenced in section `.s390_return_reg' of drivers/base/dd.o: defined in discarded section `.exit.text' of drivers/base/dd.o
> make[1]: *** [scripts/Makefile.vmlinux:34: vmlinux] Error 1
> make: *** [Makefile:1252: vmlinux] Error 2
>
> arch/s390/kernel/vmlinux.lds.S wants to keep EXIT_TEXT:
>
> .exit.text : {
> EXIT_TEXT
> }
>
> But, at the same time, EXIT_TEXT is thrown away by DISCARD because
> s390 does not define RUNTIME_DISCARD_EXIT.
>
> I still do not understand why the latter wins after 99cb0d917ffa,
> but defining RUNTIME_DISCARD_EXIT seems correct because the comment
> line in arch/s390/kernel/vmlinux.lds.S says:
>
> /*
> * .exit.text is discarded at runtime, not link time,
> * to deal with references from __bug_table
> */
>
> Nathan also found that binutils commit 21401fc7bf67 ("Duplicate output
> sections in scripts") cured this issue, so we cannot reproduce it with
> binutils 2.36+, but it is better to not rely on it.
>
> Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv")
> Link: https://lore.kernel.org/all/[email protected]/
> Reported-by: Nathan Chancellor <[email protected]>
> Signed-off-by: Masahiro Yamada <[email protected]>
> ---
>
> arch/s390/kernel/vmlinux.lds.S | 2 ++
> 1 file changed, 2 insertions(+)
Applied, thanks!