Keep 6.1 in-sync with Build ID fixes.
I've build tested this on {x86_64, arm64, riscv, powerpc, s390, sh}.
Changes for v2: - include 1/7 2348e6bf4421 ("riscv: remove special treatment for the link order of head.o") - include 2/7 994b7ac1697b ("arm64: remove special treatment for the link order of head.o") - rebase 7/7 c1c551bebf92 ("sh: define RUNTIME_DISCARD_EXIT") from upstream
Previous threads: [1] https://lore.kernel.org/all/cover.1674876902.git.tom.saeger@oracle.com/ [2] https://lore.kernel.org/all/3df32572ec7016e783d37e185f88495831671f5d.1671143... [3] https://lore.kernel.org/all/cover.1670358255.git.tom.saeger@oracle.com/
Signed-off-by: Tom Saeger tom.saeger@oracle.com --- Jisheng Zhang (1): riscv: remove special treatment for the link order of head.o
Masahiro Yamada (3): arm64: remove special treatment for the link order of head.o arch: fix broken BuildID for arm64 and riscv s390: define RUNTIME_DISCARD_EXIT to fix link error with GNU ld < 2.36
Michael Ellerman (2): powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT powerpc/vmlinux.lds: Don't discard .rela* for relocatable builds
Tom Saeger (1): sh: define RUNTIME_DISCARD_EXIT
arch/powerpc/kernel/vmlinux.lds.S | 6 +++++- arch/s390/kernel/vmlinux.lds.S | 2 ++ arch/sh/kernel/vmlinux.lds.S | 1 + include/asm-generic/vmlinux.lds.h | 5 +++++ scripts/head-object-list.txt | 2 -- 5 files changed, 13 insertions(+), 3 deletions(-) --- base-commit: d60c95efffe84428e3611431bf688f50bfc13f4e change-id: 20230210-tsaeger-upstream-linux-6-1-y-06c93fbe5bc8
Best regards,
From: Jisheng Zhang jszhang@kernel.org
commit 2348e6bf44213c5f447ff698e43c089185241ed7 upstream.
arch/riscv/kernel/head.o does not need any special treatment - the only requirement is the ".head.text" section must be placed before the normal ".text" section.
The linker script does the right thing to do. The build system does not need to manipulate the link order of head.o.
Signed-off-by: Jisheng Zhang jszhang@kernel.org Link: https://lore.kernel.org/r/20221018141200.1040-1-jszhang@kernel.org Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Tom Saeger tom.saeger@oracle.com --- scripts/head-object-list.txt | 1 - 1 file changed, 1 deletion(-)
diff --git a/scripts/head-object-list.txt b/scripts/head-object-list.txt index b16326a92c45..105ea7ac4751 100644 --- a/scripts/head-object-list.txt +++ b/scripts/head-object-list.txt @@ -39,7 +39,6 @@ arch/powerpc/kernel/entry_64.o arch/powerpc/kernel/fpu.o arch/powerpc/kernel/vector.o arch/powerpc/kernel/prom_init.o -arch/riscv/kernel/head.o arch/s390/kernel/head64.o arch/sh/kernel/head_32.o arch/sparc/kernel/head_32.o
From: Masahiro Yamada masahiroy@kernel.org
commit 994b7ac1697b4581b7726d2ac64321e3c840229b upstream.
In the previous discussion (see the Link tag), Ard pointed out that arm/arm64/kernel/head.o does not need any special treatment - the only piece that must appear right at the start of the binary image is the image header which is emitted into .head.text.
The linker script does the right thing to do. The build system does not need to manipulate the link order of head.o.
Link: https://lore.kernel.org/lkml/CAMj1kXH77Ja8bSsq2Qj8Ck9iSZKw=1F8Uy-uAWGVDm4-CG... Suggested-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Masahiro Yamada masahiroy@kernel.org Reviewed-by: Nicolas Schier nicolas@fjasle.eu Link: https://lore.kernel.org/r/20221012233500.156764-1-masahiroy@kernel.org Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Tom Saeger tom.saeger@oracle.com --- scripts/head-object-list.txt | 1 - 1 file changed, 1 deletion(-)
diff --git a/scripts/head-object-list.txt b/scripts/head-object-list.txt index 105ea7ac4751..b074134cfac2 100644 --- a/scripts/head-object-list.txt +++ b/scripts/head-object-list.txt @@ -15,7 +15,6 @@ arch/alpha/kernel/head.o arch/arc/kernel/head.o arch/arm/kernel/head-nommu.o arch/arm/kernel/head.o -arch/arm64/kernel/head.o arch/csky/kernel/head.o arch/hexagon/kernel/head.o arch/ia64/kernel/head.o
From: Masahiro Yamada masahiroy@kernel.org
commit 99cb0d917ffa1ab628bb67364ca9b162c07699b1 upstream.
Dennis Gilmore reports that the BuildID is missing in the arm64 vmlinux since commit 994b7ac1697b ("arm64: remove special treatment for the link order of head.o").
The issue is that the type of .notes section, which contains the BuildID, changed from NOTES to PROGBITS.
Ard Biesheuvel figured out that whichever object gets linked first gets to decide the type of a section. The PROGBITS type is the result of the compiler emitting .note.GNU-stack as PROGBITS rather than NOTE.
While Ard provided a fix for arm64, I want to fix this globally because the same issue is happening on riscv since commit 2348e6bf4421 ("riscv: remove special treatment for the link order of head.o"). This problem will happen in general for other architectures if they start to drop unneeded entries from scripts/head-object-list.txt.
Discard .note.GNU-stack in include/asm-generic/vmlinux.lds.h.
Link: https://lore.kernel.org/lkml/CAABkxwuQoz1CTbyb57n0ZX65eSYiTonFCU8-LCQc=74D=x... Fixes: 994b7ac1697b ("arm64: remove special treatment for the link order of head.o") Fixes: 2348e6bf4421 ("riscv: remove special treatment for the link order of head.o") Reported-by: Dennis Gilmore dennis@ausil.us Suggested-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Masahiro Yamada masahiroy@kernel.org Acked-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Tom Saeger tom.saeger@oracle.com --- include/asm-generic/vmlinux.lds.h | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 3dc5824141cd..7ad6f51b3d91 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -929,7 +929,12 @@ #define PRINTK_INDEX #endif
+/* + * Discard .note.GNU-stack, which is emitted as PROGBITS by the compiler. + * Otherwise, the type of .notes section would become PROGBITS instead of NOTES. + */ #define NOTES \ + /DISCARD/ : { *(.note.GNU-stack) } \ .notes : AT(ADDR(.notes) - LOAD_OFFSET) { \ __start_notes = .; \ KEEP(*(.note.*)) \
From: Michael Ellerman mpe@ellerman.id.au
commit 4b9880dbf3bdba3a7c56445137c3d0e30aaa0a40 upstream.
The powerpc linker script explicitly includes .exit.text, because otherwise the link fails due to references from __bug_table and __ex_table. The code is freed (discarded) at runtime along with .init.text and data.
That has worked in the past despite powerpc not defining RUNTIME_DISCARD_EXIT because DISCARDS appears late in the powerpc linker script (line 410), and the explicit inclusion of .exit.text earlier (line 280) supersedes the discard.
However commit 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv") introduced an earlier use of DISCARD as part of the RO_DATA macro (line 136). With binutils < 2.36 that causes the DISCARD directives later in the script to be applied earlier [1], causing .exit.text to actually be discarded at link time, leading to build errors:
'.exit.text' referenced in section '__bug_table' of crypto/algboss.o: defined in discarded section '.exit.text' of crypto/algboss.o '.exit.text' referenced in section '__ex_table' of drivers/nvdimm/core.o: defined in discarded section '.exit.text' of drivers/nvdimm/core.o
Fix it by defining RUNTIME_DISCARD_EXIT, which causes the generic DISCARDS macro to not include .exit.text at all.
1: https://lore.kernel.org/lkml/87fscp2v7k.fsf@igel.home/
Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv") Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/20230105132349.384666-1-mpe@ellerman.id.au Signed-off-by: Tom Saeger tom.saeger@oracle.com --- arch/powerpc/kernel/vmlinux.lds.S | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index 8c3862b4c259..c5ea7d03d539 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -8,6 +8,7 @@ #define BSS_FIRST_SECTIONS *(.bss.prominit) #define EMITS_PT_NOTE #define RO_EXCEPTION_TABLE_ALIGN 0 +#define RUNTIME_DISCARD_EXIT
#define SOFT_MASK_TABLE(align) \ . = ALIGN(align); \
From: Michael Ellerman mpe@ellerman.id.au
commit 07b050f9290ee012a407a0f64151db902a1520f5 upstream.
Relocatable kernels must not discard relocations, they need to be processed at runtime. As such they are included for CONFIG_RELOCATABLE builds in the powerpc linker script (line 340).
However they are also unconditionally discarded later in the script (line 414). Previously that worked because the earlier inclusion superseded the discard.
However commit 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv") introduced an earlier use of DISCARD as part of the RO_DATA macro (line 137). With binutils < 2.36 that causes the DISCARD directives later in the script to be applied earlier, causing .rela* to actually be discarded at link time, leading to build warnings and a kernel that doesn't boot:
ld: warning: discarding dynamic section .rela.init.rodata
Fix it by conditionally discarding .rela* only when CONFIG_RELOCATABLE is disabled.
Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv") Signed-off-by: Michael Ellerman mpe@ellerman.id.au
Link: https://lore.kernel.org/r/20230105132349.384666-2-mpe@ellerman.id.au Signed-off-by: Tom Saeger tom.saeger@oracle.com --- arch/powerpc/kernel/vmlinux.lds.S | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index c5ea7d03d539..a4c6efadc90c 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -411,9 +411,12 @@ SECTIONS DISCARDS /DISCARD/ : { *(*.EMB.apuinfo) - *(.glink .iplt .plt .rela* .comment) + *(.glink .iplt .plt .comment) *(.gnu.version*) *(.gnu.attributes) *(.eh_frame) +#ifndef CONFIG_RELOCATABLE + *(.rela*) +#endif } }
From: Masahiro Yamada masahiroy@kernel.org
commit a494398bde273143c2352dd373cad8211f7d94b2 upstream.
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/Y7Jal56f6UBh1abE@dev-arch.thelio-3990X/ Reported-by: Nathan Chancellor nathan@kernel.org Signed-off-by: Masahiro Yamada masahiroy@kernel.org Link: https://lore.kernel.org/r/20230105031306.1455409-1-masahiroy@kernel.org Signed-off-by: Heiko Carstens hca@linux.ibm.com Signed-off-by: Tom Saeger tom.saeger@oracle.com --- 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 f81d96710595..cbf9c1b0beda 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>
commit c1c551bebf928889e7a8fef7415b44f9a64975f4 upstream.
sh vmlinux fails to link with GNU ld < 2.40 (likely < 2.36) since commit 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv").
This is similar to fixes for powerpc and s390: commit 4b9880dbf3bd ("powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT"). commit a494398bde27 ("s390: define RUNTIME_DISCARD_EXIT to fix link error with GNU ld < 2.36").
$ sh4-linux-gnu-ld --version | head -n1 GNU ld (GNU Binutils for Debian) 2.35.2
$ make ARCH=sh CROSS_COMPILE=sh4-linux-gnu- microdev_defconfig $ make ARCH=sh CROSS_COMPILE=sh4-linux-gnu-
`.exit.text' referenced in section `__bug_table' of crypto/algboss.o: defined in discarded section `.exit.text' of crypto/algboss.o `.exit.text' referenced in section `__bug_table' of drivers/char/hw_random/core.o: defined in discarded section `.exit.text' of drivers/char/hw_random/core.o make[2]: *** [scripts/Makefile.vmlinux:34: vmlinux] Error 1 make[1]: *** [Makefile:1252: vmlinux] Error 2
arch/sh/kernel/vmlinux.lds.S keeps EXIT_TEXT:
/* * .exit.text is discarded at runtime, not link time, to deal with * references from __bug_table */ .exit.text : AT(ADDR(.exit.text)) { EXIT_TEXT }
However, EXIT_TEXT is thrown away by DISCARD(include/asm-generic/vmlinux.lds.h) because sh does not define RUNTIME_DISCARD_EXIT.
GNU ld 2.40 does not have this issue and builds fine. This corresponds with Masahiro's comments in a494398bde27: "Nathan [Chancellor] 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."
Link: https://lkml.kernel.org/r/9166a8abdc0f979e50377e61780a4bba1dfa2f52.167451846... Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv") Link: https://lore.kernel.org/all/Y7Jal56f6UBh1abE@dev-arch.thelio-3990X/ Link: https://lore.kernel.org/all/20230123194218.47ssfzhrpnv3xfez@oracle.com/ Signed-off-by: Tom Saeger tom.saeger@oracle.com Tested-by: John Paul Adrian Glaubitz glaubitz@physik.fu-berlin.de Cc: Ard Biesheuvel ardb@kernel.org Cc: Arnd Bergmann arnd@arndb.de Cc: Christoph Hellwig hch@lst.de Cc: Dennis Gilmore dennis@ausil.us Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: Masahiro Yamada masahiroy@kernel.org Cc: Naresh Kamboju naresh.kamboju@linaro.org Cc: Nathan Chancellor nathan@kernel.org Cc: Palmer Dabbelt palmer@rivosinc.com Cc: Rich Felker dalias@libc.org Cc: Yoshinori Sato ysato@users.sourceforge.jp Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Tom Saeger tom.saeger@oracle.com --- arch/sh/kernel/vmlinux.lds.S | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/sh/kernel/vmlinux.lds.S b/arch/sh/kernel/vmlinux.lds.S index 3161b9ccd2a5..b6276a3521d7 100644 --- a/arch/sh/kernel/vmlinux.lds.S +++ b/arch/sh/kernel/vmlinux.lds.S @@ -4,6 +4,7 @@ * Written by Niibe Yutaka and Paul Mundt */ OUTPUT_ARCH(sh) +#define RUNTIME_DISCARD_EXIT #include <asm/thread_info.h> #include <asm/cache.h> #include <asm/vmlinux.lds.h>
On Fri, Feb 10, 2023 at 01:17:15PM -0700, Tom Saeger wrote:
Keep 6.1 in-sync with Build ID fixes.
I've build tested this on {x86_64, arm64, riscv, powerpc, s390, sh}.
Changes for v2:
- include 1/7 2348e6bf4421 ("riscv: remove special treatment for the link order of head.o")
- include 2/7 994b7ac1697b ("arm64: remove special treatment for the link order of head.o")
- rebase 7/7 c1c551bebf92 ("sh: define RUNTIME_DISCARD_EXIT") from upstream
Previous threads: [1] https://lore.kernel.org/all/cover.1674876902.git.tom.saeger@oracle.com/ [2] https://lore.kernel.org/all/3df32572ec7016e783d37e185f88495831671f5d.1671143... [3] https://lore.kernel.org/all/cover.1670358255.git.tom.saeger@oracle.com/
Signed-off-by: Tom Saeger tom.saeger@oracle.com
Jisheng Zhang (1): riscv: remove special treatment for the link order of head.o
Masahiro Yamada (3): arm64: remove special treatment for the link order of head.o arch: fix broken BuildID for arm64 and riscv s390: define RUNTIME_DISCARD_EXIT to fix link error with GNU ld < 2.36
Michael Ellerman (2): powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT powerpc/vmlinux.lds: Don't discard .rela* for relocatable builds
Tom Saeger (1): sh: define RUNTIME_DISCARD_EXIT
arch/powerpc/kernel/vmlinux.lds.S | 6 +++++- arch/s390/kernel/vmlinux.lds.S | 2 ++ arch/sh/kernel/vmlinux.lds.S | 1 + include/asm-generic/vmlinux.lds.h | 5 +++++ scripts/head-object-list.txt | 2 -- 5 files changed, 13 insertions(+), 3 deletions(-)
base-commit: d60c95efffe84428e3611431bf688f50bfc13f4e change-id: 20230210-tsaeger-upstream-linux-6-1-y-06c93fbe5bc8
Now queued up, thanks.
greg k-h
linux-stable-mirror@lists.linaro.org