linux.git/scripts/link-vmlinux.sh, branch v5.15.185 Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git kbuild: fix short log for AS in link-vmlinux.sh 2024-07-18T11:07:36+00:00 Masahiro Yamada masahiroy@kernel.org 2024-05-20T12:42:11+00:00 f44608dd02119d1e3cdcc673e7e9a51d2d469ef9 [ Upstream commit 3430f65d6130ccbc86f0ff45642eeb9e2032a600 ] In convention, short logs print the output file, not the input file. Let's change the suffix for 'AS' since it assembles *.S into *.o. [Before] LD .tmp_vmlinux.kallsyms1 NM .tmp_vmlinux.kallsyms1.syms KSYMS .tmp_vmlinux.kallsyms1.S AS .tmp_vmlinux.kallsyms1.S LD .tmp_vmlinux.kallsyms2 NM .tmp_vmlinux.kallsyms2.syms KSYMS .tmp_vmlinux.kallsyms2.S AS .tmp_vmlinux.kallsyms2.S LD vmlinux [After] LD .tmp_vmlinux.kallsyms1 NM .tmp_vmlinux.kallsyms1.syms KSYMS .tmp_vmlinux.kallsyms1.S AS .tmp_vmlinux.kallsyms1.o LD .tmp_vmlinux.kallsyms2 NM .tmp_vmlinux.kallsyms2.syms KSYMS .tmp_vmlinux.kallsyms2.S AS .tmp_vmlinux.kallsyms2.o LD vmlinux Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 3430f65d6130ccbc86f0ff45642eeb9e2032a600 ]

In convention, short logs print the output file, not the input file.

Let's change the suffix for 'AS' since it assembles *.S into *.o.

[Before]

  LD      .tmp_vmlinux.kallsyms1
  NM      .tmp_vmlinux.kallsyms1.syms
  KSYMS   .tmp_vmlinux.kallsyms1.S
  AS      .tmp_vmlinux.kallsyms1.S
  LD      .tmp_vmlinux.kallsyms2
  NM      .tmp_vmlinux.kallsyms2.syms
  KSYMS   .tmp_vmlinux.kallsyms2.S
  AS      .tmp_vmlinux.kallsyms2.S
  LD      vmlinux

[After]

  LD      .tmp_vmlinux.kallsyms1
  NM      .tmp_vmlinux.kallsyms1.syms
  KSYMS   .tmp_vmlinux.kallsyms1.S
  AS      .tmp_vmlinux.kallsyms1.o
  LD      .tmp_vmlinux.kallsyms2
  NM      .tmp_vmlinux.kallsyms2.syms
  KSYMS   .tmp_vmlinux.kallsyms2.S
  AS      .tmp_vmlinux.kallsyms2.o
  LD      vmlinux

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
kbuild: Fix changing ELF file type for output of gen_btf for big endian 2024-02-23T07:55:05+00:00 Nathan Chancellor nathan@kernel.org 2024-02-13T02:05:10+00:00 ac0f160a364e9312ccbb7a5adae3ce06e9dd7c24 commit e3a9ee963ad8ba677ca925149812c5932b49af69 upstream. Commit 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF") changed the ELF type of .btf.vmlinux.bin.o to ET_REL via dd, which works fine for little endian platforms: 00000000 7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00 |.ELF............| -00000010 03 00 b7 00 01 00 00 00 00 00 00 80 00 80 ff ff |................| +00000010 01 00 b7 00 01 00 00 00 00 00 00 80 00 80 ff ff |................| However, for big endian platforms, it changes the wrong byte, resulting in an invalid ELF file type, which ld.lld rejects: 00000000 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00 |.ELF............| -00000010 00 03 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................| +00000010 01 03 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................| Type: <unknown>: 103 ld.lld: error: .btf.vmlinux.bin.o: unknown file type Fix this by updating the entire 16-bit e_type field rather than just a single byte, so that everything works correctly for all platforms and linkers. 00000000 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00 |.ELF............| -00000010 00 03 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................| +00000010 00 01 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................| Type: REL (Relocatable file) While in the area, update the comment to mention that binutils 2.35+ matches LLD's behavior of rejecting an ET_EXEC input, which occurred after the comment was added. Cc: stable@vger.kernel.org Fixes: 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF") Link: https://github.com/llvm/llvm-project/pull/75643 Suggested-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Fangrui Song <maskray@google.com> Reviewed-by: Nicolas Schier <nicolas@fjasle.eu> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Justin Stitt <justinstitt@google.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> [nathan: Fix silent conflict due to lack of 7d153696e5db in older trees] Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e3a9ee963ad8ba677ca925149812c5932b49af69 upstream.

Commit 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF")
changed the ELF type of .btf.vmlinux.bin.o to ET_REL via dd, which works
fine for little endian platforms:

   00000000  7f 45 4c 46 02 01 01 00  00 00 00 00 00 00 00 00  |.ELF............|
  -00000010  03 00 b7 00 01 00 00 00  00 00 00 80 00 80 ff ff  |................|
  +00000010  01 00 b7 00 01 00 00 00  00 00 00 80 00 80 ff ff  |................|

However, for big endian platforms, it changes the wrong byte, resulting
in an invalid ELF file type, which ld.lld rejects:

   00000000  7f 45 4c 46 02 02 01 00  00 00 00 00 00 00 00 00  |.ELF............|
  -00000010  00 03 00 16 00 00 00 01  00 00 00 00 00 10 00 00  |................|
  +00000010  01 03 00 16 00 00 00 01  00 00 00 00 00 10 00 00  |................|

  Type:                              <unknown>: 103

  ld.lld: error: .btf.vmlinux.bin.o: unknown file type

Fix this by updating the entire 16-bit e_type field rather than just a
single byte, so that everything works correctly for all platforms and
linkers.

   00000000  7f 45 4c 46 02 02 01 00  00 00 00 00 00 00 00 00  |.ELF............|
  -00000010  00 03 00 16 00 00 00 01  00 00 00 00 00 10 00 00  |................|
  +00000010  00 01 00 16 00 00 00 01  00 00 00 00 00 10 00 00  |................|

  Type:                              REL (Relocatable file)

While in the area, update the comment to mention that binutils 2.35+
matches LLD's behavior of rejecting an ET_EXEC input, which occurred
after the comment was added.

Cc: stable@vger.kernel.org
Fixes: 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF")
Link: https://github.com/llvm/llvm-project/pull/75643
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Fangrui Song <maskray@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
[nathan: Fix silent conflict due to lack of 7d153696e5db in older trees]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kbuild: Unify options for BTF generation for vmlinux and modules 2022-09-08T10:28:08+00:00 Jiri Olsa jolsa@redhat.com 2022-09-04T13:19:00+00:00 0baced0e0938f2895ceba54038eaf15ed91032e7 commit e27f05147bff21408c1b8410ad8e90cd286e7952 upstream. Using new PAHOLE_FLAGS variable to pass extra arguments to pahole for both vmlinux and modules BTF data generation. Adding new scripts/pahole-flags.sh script that detect and prints pahole options. [ fixed issues found by kernel test robot ] Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211029125729.70002-1-jolsa@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e27f05147bff21408c1b8410ad8e90cd286e7952 upstream.

Using new PAHOLE_FLAGS variable to pass extra arguments to
pahole for both vmlinux and modules BTF data generation.

Adding new scripts/pahole-flags.sh script that detect and
prints pahole options.

[ fixed issues found by kernel test robot ]

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211029125729.70002-1-jolsa@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86/retbleed: Add fine grained Kconfig knobs 2022-07-23T10:54:10+00:00 Peter Zijlstra peterz@infradead.org 2022-06-27T22:21:17+00:00 cc3011cdbe5f834b0e9873b841d1be02be9a1524 commit f43b9876e857c739d407bc56df288b0ebe1a9164 upstream. Do fine-grained Kconfig for all the various retbleed parts. NOTE: if your compiler doesn't support return thunks this will silently 'upgrade' your mitigation to IBPB, you might not like this. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> [cascardo: there is no CONFIG_OBJTOOL] [cascardo: objtool calling and option parsing has changed] Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f43b9876e857c739d407bc56df288b0ebe1a9164 upstream.

Do fine-grained Kconfig for all the various retbleed parts.

NOTE: if your compiler doesn't support return thunks this will
silently 'upgrade' your mitigation to IBPB, you might not like this.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
[cascardo: there is no CONFIG_OBJTOOL]
[cascardo: objtool calling and option parsing has changed]
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
objtool: Add entry UNRET validation 2022-07-23T10:54:06+00:00 Peter Zijlstra peterz@infradead.org 2022-06-14T21:16:03+00:00 dab72c3c32ccde4f362fff993759b0133448d394 commit a09a6e2399ba0595c3042b3164f3ca68a3cff33e upstream. Since entry asm is tricky, add a validation pass that ensures the retbleed mitigation has been done before the first actual RET instruction. Entry points are those that either have UNWIND_HINT_ENTRY, which acts as UNWIND_HINT_EMPTY but marks the instruction as an entry point, or those that have UWIND_HINT_IRET_REGS at +0. This is basically a variant of validate_branch() that is intra-function and it will simply follow all branches from marked entry points and ensures that all paths lead to ANNOTATE_UNRET_END. If a path hits RET or an indirection the path is a fail and will be reported. There are 3 ANNOTATE_UNRET_END instances: - UNTRAIN_RET itself - exception from-kernel; this path doesn't need UNTRAIN_RET - all early exceptions; these also don't need UNTRAIN_RET Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> [cascardo: tools/objtool/builtin-check.c no link option validation] [cascardo: tools/objtool/check.c opts.ibt is ibt] [cascardo: tools/objtool/include/objtool/builtin.h leave unret option as bool, no struct opts] [cascardo: objtool is still called from scripts/link-vmlinux.sh] [cascardo: no IBT support] Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a09a6e2399ba0595c3042b3164f3ca68a3cff33e upstream.

Since entry asm is tricky, add a validation pass that ensures the
retbleed mitigation has been done before the first actual RET
instruction.

Entry points are those that either have UNWIND_HINT_ENTRY, which acts
as UNWIND_HINT_EMPTY but marks the instruction as an entry point, or
those that have UWIND_HINT_IRET_REGS at +0.

This is basically a variant of validate_branch() that is
intra-function and it will simply follow all branches from marked
entry points and ensures that all paths lead to ANNOTATE_UNRET_END.

If a path hits RET or an indirection the path is a fail and will be
reported.

There are 3 ANNOTATE_UNRET_END instances:

 - UNTRAIN_RET itself
 - exception from-kernel; this path doesn't need UNTRAIN_RET
 - all early exceptions; these also don't need UNTRAIN_RET

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
[cascardo: tools/objtool/builtin-check.c no link option validation]
[cascardo: tools/objtool/check.c opts.ibt is ibt]
[cascardo: tools/objtool/include/objtool/builtin.h leave unret option as bool, no struct opts]
[cascardo: objtool is still called from scripts/link-vmlinux.sh]
[cascardo: no IBT support]
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86: Add straight-line-speculation mitigation 2022-05-15T18:18:51+00:00 Peter Zijlstra peterz@infradead.org 2021-12-04T13:43:44+00:00 370d33da35e31c1544eb77bcf2539f09b1064b9c [ Upstream commit e463a09af2f0677b9485a7e8e4e70b396b2ffb6f ] Make use of an upcoming GCC feature to mitigate straight-line-speculation for x86: https://gcc.gnu.org/g:53a643f8568067d7700a9f2facc8ba39974973d3 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102952 https://bugs.llvm.org/show_bug.cgi?id=52323 It's built tested on x86_64-allyesconfig using GCC-12 and GCC-11. Maintenance overhead of this should be fairly low due to objtool validation. Size overhead of all these additional int3 instructions comes to: text data bss dec hex filename 22267751 6933356 2011368 31212475 1dc43bb defconfig-build/vmlinux 22804126 6933356 1470696 31208178 1dc32f2 defconfig-build/vmlinux.sls Or roughly 2.4% additional text. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20211204134908.140103474@infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit e463a09af2f0677b9485a7e8e4e70b396b2ffb6f ]

Make use of an upcoming GCC feature to mitigate
straight-line-speculation for x86:

  https://gcc.gnu.org/g:53a643f8568067d7700a9f2facc8ba39974973d3
  https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102952
  https://bugs.llvm.org/show_bug.cgi?id=52323

It's built tested on x86_64-allyesconfig using GCC-12 and GCC-11.

Maintenance overhead of this should be fairly low due to objtool
validation.

Size overhead of all these additional int3 instructions comes to:

     text	   data	    bss	    dec	    hex	filename
  22267751	6933356	2011368	31212475	1dc43bb	defconfig-build/vmlinux
  22804126	6933356	1470696	31208178	1dc32f2	defconfig-build/vmlinux.sls

Or roughly 2.4% additional text.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211204134908.140103474@infradead.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kbuild: merge vmlinux_link() between ARCH=um and other architectures 2021-09-02T23:17:21+00:00 Masahiro Yamada masahiroy@kernel.org 2021-08-19T00:57:39+00:00 5df77ad61fd71b1b342ba40d913ad5595480691c For ARCH=um, ${CC} is used as the linker driver. Hence, the linker options are prefixed with -Wl, . Merge the similar code. I replaced the -T option with the long option --script= so that it works well with/without ${wl}. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> 
For ARCH=um, ${CC} is used as the linker driver. Hence, the linker
options are prefixed with -Wl, .

Merge the similar code.

I replaced the -T option with the long option --script= so that it
works well with/without ${wl}.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
kbuild: do not remove 'linux' link in scripts/link-vmlinux.sh 2021-09-02T23:17:21+00:00 Masahiro Yamada masahiroy@kernel.org 2021-08-19T00:57:38+00:00 d40aecd108d2a6413d53f6f8339e787a23150595 arch/um/Makefile passes the -f option to the ln command: linux: vmlinux @echo ' LINK $@' $(Q)ln -f $< $@ So, the hard link is always re-created, and the old one is removed anyway. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> 
arch/um/Makefile passes the -f option to the ln command:

  linux: vmlinux
          @echo '  LINK $@'
          $(Q)ln -f $< $@

So, the hard link is always re-created, and the old one is removed
anyway.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
kbuild: merge vmlinux_link() between the ordinary link and Clang LTO 2021-09-02T23:17:20+00:00 Masahiro Yamada masahiroy@kernel.org 2021-08-19T00:57:37+00:00 8f1305124ea48943d1dd07683ed4f82c69b232ee When Clang LTO is enabled, vmlinux_link() reuses vmlinux.o instead of re-linking ${KBUILD_VMLINUX_OBJS} and ${KBUILD_VMLINUX_LIBS}. That is the only difference here, so merge the similar code. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> 
When Clang LTO is enabled, vmlinux_link() reuses vmlinux.o instead of
re-linking ${KBUILD_VMLINUX_OBJS} and ${KBUILD_VMLINUX_LIBS}.

That is the only difference here, so merge the similar code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Merge tag 'kbuild-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild 2021-07-10T18:01:38+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-07-10T18:01:38+00:00 81361b837a3450f0a44255fddfd7a4c72502b667 Pull Kbuild updates from Masahiro Yamada: - Increase the -falign-functions alignment for the debug option. - Remove ugly libelf checks from the top Makefile. - Make the silent build (-s) more silent. - Re-compile the kernel if KBUILD_BUILD_TIMESTAMP is specified. - Various script cleanups * tag 'kbuild-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (27 commits) scripts: add generic syscallnr.sh scripts: check duplicated syscall number in syscall table sparc: syscalls: use pattern rules to generate syscall headers parisc: syscalls: use pattern rules to generate syscall headers nds32: add arch/nds32/boot/.gitignore kbuild: mkcompile_h: consider timestamp if KBUILD_BUILD_TIMESTAMP is set kbuild: modpost: Explicitly warn about unprototyped symbols kbuild: remove trailing slashes from $(KBUILD_EXTMOD) kconfig.h: explain IS_MODULE(), IS_ENABLED() kconfig: constify long_opts scripts/setlocalversion: simplify the short version part scripts/setlocalversion: factor out 12-chars hash construction scripts/setlocalversion: add more comments to -dirty flag detection scripts/setlocalversion: remove workaround for old make-kpkg scripts/setlocalversion: remove mercurial, svn and git-svn supports kbuild: clean up ${quiet} checks in shell scripts kbuild: sink stdout from cmd for silent build init: use $(call cmd,) for generating include/generated/compile.h kbuild: merge scripts/mkmakefile to top Makefile sh: move core-y in arch/sh/Makefile to arch/sh/Kbuild ... 
Pull Kbuild updates from Masahiro Yamada:

 - Increase the -falign-functions alignment for the debug option.

 - Remove ugly libelf checks from the top Makefile.

 - Make the silent build (-s) more silent.

 - Re-compile the kernel if KBUILD_BUILD_TIMESTAMP is specified.

 - Various script cleanups

* tag 'kbuild-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (27 commits)
  scripts: add generic syscallnr.sh
  scripts: check duplicated syscall number in syscall table
  sparc: syscalls: use pattern rules to generate syscall headers
  parisc: syscalls: use pattern rules to generate syscall headers
  nds32: add arch/nds32/boot/.gitignore
  kbuild: mkcompile_h: consider timestamp if KBUILD_BUILD_TIMESTAMP is set
  kbuild: modpost: Explicitly warn about unprototyped symbols
  kbuild: remove trailing slashes from $(KBUILD_EXTMOD)
  kconfig.h: explain IS_MODULE(), IS_ENABLED()
  kconfig: constify long_opts
  scripts/setlocalversion: simplify the short version part
  scripts/setlocalversion: factor out 12-chars hash construction
  scripts/setlocalversion: add more comments to -dirty flag detection
  scripts/setlocalversion: remove workaround for old make-kpkg
  scripts/setlocalversion: remove mercurial, svn and git-svn supports
  kbuild: clean up ${quiet} checks in shell scripts
  kbuild: sink stdout from cmd for silent build
  init: use $(call cmd,) for generating include/generated/compile.h
  kbuild: merge scripts/mkmakefile to top Makefile
  sh: move core-y in arch/sh/Makefile to arch/sh/Kbuild
  ...