linux-stable.git/include/asm-generic/vmlinux.lds.h, branch v5.13.2 Linux kernel stable tree vmlinux.lds.h: Avoid orphan section with !SMP 2021-06-02T19:43:55+00:00 Nathan Chancellor nathan@kernel.org 2021-05-06T00:14:11+00:00 d4c6399900364facd84c9e35ce1540b6046c345f With x86_64_defconfig and the following configs, there is an orphan section warning: CONFIG_SMP=n CONFIG_AMD_MEM_ENCRYPT=y CONFIG_HYPERVISOR_GUEST=y CONFIG_KVM=y CONFIG_PARAVIRT=y ld: warning: orphan section `.data..decrypted' from `arch/x86/kernel/cpu/vmware.o' being placed in section `.data..decrypted' ld: warning: orphan section `.data..decrypted' from `arch/x86/kernel/kvm.o' being placed in section `.data..decrypted' These sections are created with DEFINE_PER_CPU_DECRYPTED, which ultimately turns into __PCPU_ATTRS, which in turn has a section attribute with a value of PER_CPU_BASE_SECTION + the section name. When CONFIG_SMP is not set, the base section is .data and that is not currently handled in any linker script. Add .data..decrypted to PERCPU_DECRYPTED_SECTION, which is included in PERCPU_INPUT -> PERCPU_SECTION, which is include in the x86 linker script when either CONFIG_X86_64 or CONFIG_SMP is unset, taking care of the warning. Fixes: ac26963a1175 ("percpu: Introduce DEFINE_PER_CPU_DECRYPTED") Link: https://github.com/ClangBuiltLinux/linux/issues/1360 Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> # build Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210506001410.1026691-1-nathan@kernel.org 
With x86_64_defconfig and the following configs, there is an orphan
section warning:

CONFIG_SMP=n
CONFIG_AMD_MEM_ENCRYPT=y
CONFIG_HYPERVISOR_GUEST=y
CONFIG_KVM=y
CONFIG_PARAVIRT=y

ld: warning: orphan section `.data..decrypted' from `arch/x86/kernel/cpu/vmware.o' being placed in section `.data..decrypted'
ld: warning: orphan section `.data..decrypted' from `arch/x86/kernel/kvm.o' being placed in section `.data..decrypted'

These sections are created with DEFINE_PER_CPU_DECRYPTED, which
ultimately turns into __PCPU_ATTRS, which in turn has a section
attribute with a value of PER_CPU_BASE_SECTION + the section name. When
CONFIG_SMP is not set, the base section is .data and that is not
currently handled in any linker script.

Add .data..decrypted to PERCPU_DECRYPTED_SECTION, which is included in
PERCPU_INPUT -> PERCPU_SECTION, which is include in the x86 linker
script when either CONFIG_X86_64 or CONFIG_SMP is unset, taking care of
the warning.

Fixes: ac26963a1175 ("percpu: Introduce DEFINE_PER_CPU_DECRYPTED")
Link: https://github.com/ClangBuiltLinux/linux/issues/1360
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com> # build
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210506001410.1026691-1-nathan@kernel.org
add support for Clang CFI 2021-04-08T23:04:20+00:00 Sami Tolvanen samitolvanen@google.com 2021-04-08T18:28:26+00:00 cf68fffb66d60d96209446bfc4a15291dc5a5d41 This change adds support for Clang’s forward-edge Control Flow Integrity (CFI) checking. With CONFIG_CFI_CLANG, the compiler injects a runtime check before each indirect function call to ensure the target is a valid function with the correct static type. This restricts possible call targets and makes it more difficult for an attacker to exploit bugs that allow the modification of stored function pointers. For more details, see: https://clang.llvm.org/docs/ControlFlowIntegrity.html Clang requires CONFIG_LTO_CLANG to be enabled with CFI to gain visibility to possible call targets. Kernel modules are supported with Clang’s cross-DSO CFI mode, which allows checking between independently compiled components. With CFI enabled, the compiler injects a __cfi_check() function into the kernel and each module for validating local call targets. For cross-module calls that cannot be validated locally, the compiler calls the global __cfi_slowpath_diag() function, which determines the target module and calls the correct __cfi_check() function. This patch includes a slowpath implementation that uses __module_address() to resolve call targets, and with CONFIG_CFI_CLANG_SHADOW enabled, a shadow map that speeds up module look-ups by ~3x. Clang implements indirect call checking using jump tables and offers two methods of generating them. With canonical jump tables, the compiler renames each address-taken function to <function>.cfi and points the original symbol to a jump table entry, which passes __cfi_check() validation. This isn’t compatible with stand-alone assembly code, which the compiler doesn’t instrument, and would result in indirect calls to assembly code to fail. Therefore, we default to using non-canonical jump tables instead, where the compiler generates a local jump table entry <function>.cfi_jt for each address-taken function, and replaces all references to the function with the address of the jump table entry. Note that because non-canonical jump table addresses are local to each component, they break cross-module function address equality. Specifically, the address of a global function will be different in each module, as it's replaced with the address of a local jump table entry. If this address is passed to a different module, it won’t match the address of the same function taken there. This may break code that relies on comparing addresses passed from other components. CFI checking can be disabled in a function with the __nocfi attribute. Additionally, CFI can be disabled for an entire compilation unit by filtering out CC_FLAGS_CFI. By default, CFI failures result in a kernel panic to stop a potential exploit. CONFIG_CFI_PERMISSIVE enables a permissive mode, where the kernel prints out a rate-limited warning instead, and allows execution to continue. This option is helpful for locating type mismatches, but should only be enabled during development. Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210408182843.1754385-2-samitolvanen@google.com 
This change adds support for Clang’s forward-edge Control Flow
Integrity (CFI) checking. With CONFIG_CFI_CLANG, the compiler
injects a runtime check before each indirect function call to ensure
the target is a valid function with the correct static type. This
restricts possible call targets and makes it more difficult for
an attacker to exploit bugs that allow the modification of stored
function pointers. For more details, see:

  https://clang.llvm.org/docs/ControlFlowIntegrity.html

Clang requires CONFIG_LTO_CLANG to be enabled with CFI to gain
visibility to possible call targets. Kernel modules are supported
with Clang’s cross-DSO CFI mode, which allows checking between
independently compiled components.

With CFI enabled, the compiler injects a __cfi_check() function into
the kernel and each module for validating local call targets. For
cross-module calls that cannot be validated locally, the compiler
calls the global __cfi_slowpath_diag() function, which determines
the target module and calls the correct __cfi_check() function. This
patch includes a slowpath implementation that uses __module_address()
to resolve call targets, and with CONFIG_CFI_CLANG_SHADOW enabled, a
shadow map that speeds up module look-ups by ~3x.

Clang implements indirect call checking using jump tables and
offers two methods of generating them. With canonical jump tables,
the compiler renames each address-taken function to <function>.cfi
and points the original symbol to a jump table entry, which passes
__cfi_check() validation. This isn’t compatible with stand-alone
assembly code, which the compiler doesn’t instrument, and would
result in indirect calls to assembly code to fail. Therefore, we
default to using non-canonical jump tables instead, where the compiler
generates a local jump table entry <function>.cfi_jt for each
address-taken function, and replaces all references to the function
with the address of the jump table entry.

Note that because non-canonical jump table addresses are local
to each component, they break cross-module function address
equality. Specifically, the address of a global function will be
different in each module, as it's replaced with the address of a local
jump table entry. If this address is passed to a different module,
it won’t match the address of the same function taken there. This
may break code that relies on comparing addresses passed from other
components.

CFI checking can be disabled in a function with the __nocfi attribute.
Additionally, CFI can be disabled for an entire compilation unit by
filtering out CC_FLAGS_CFI.

By default, CFI failures result in a kernel panic to stop a potential
exploit. CONFIG_CFI_PERMISSIVE enables a permissive mode, where the
kernel prints out a rate-limited warning instead, and allows execution
to continue. This option is helpful for locating type mismatches, but
should only be enabled during development.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210408182843.1754385-2-samitolvanen@google.com
Merge tag 'orphan-handling-v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux 2021-02-26T18:12:19+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-02-26T18:12:19+00:00 2bd3f4eeb3147330d03df56f79378f12f25d73de Pull orphan handling fix from Kees Cook: "Another case of bogus .eh_frame emission was noticed under CONFIG_GCOV_KERNEL=y. Summary: - Define SANITIZER_DISCARDS with CONFIG_GCOV_KERNEL=y (Nathan Chancellor)" * tag 'orphan-handling-v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: vmlinux.lds.h: Define SANITIZER_DISCARDS with CONFIG_GCOV_KERNEL=y 
Pull orphan handling fix from Kees Cook:
 "Another case of bogus .eh_frame emission was noticed under
  CONFIG_GCOV_KERNEL=y.

  Summary:

   - Define SANITIZER_DISCARDS with CONFIG_GCOV_KERNEL=y (Nathan
     Chancellor)"

* tag 'orphan-handling-v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  vmlinux.lds.h: Define SANITIZER_DISCARDS with CONFIG_GCOV_KERNEL=y
vmlinux.lds.h: Define SANTIZER_DISCARDS with CONFIG_GCOV_KERNEL=y 2021-02-25T21:15:25+00:00 Nathan Chancellor nathan@kernel.org 2021-01-30T00:46:51+00:00 f5b6a74d9c08b19740ca056876bf6584acdba582 clang produces .eh_frame sections when CONFIG_GCOV_KERNEL is enabled, even when -fno-asynchronous-unwind-tables is in KBUILD_CFLAGS: $ make CC=clang vmlinux ... ld: warning: orphan section `.eh_frame' from `init/main.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/version.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/do_mounts.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/do_mounts_initrd.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/initramfs.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/calibrate.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/init_task.o' being placed in section `.eh_frame' ... $ rg "GCOV_KERNEL|GCOV_PROFILE_ALL" .config CONFIG_GCOV_KERNEL=y CONFIG_ARCH_HAS_GCOV_PROFILE_ALL=y CONFIG_GCOV_PROFILE_ALL=y This was already handled for a couple of other options in commit d812db78288d ("vmlinux.lds.h: Avoid KASAN and KCSAN's unwanted sections") and there is an open LLVM bug for this issue. Take advantage of that section for this config as well so that there are no more orphan warnings. Link: https://bugs.llvm.org/show_bug.cgi?id=46478 Link: https://github.com/ClangBuiltLinux/linux/issues/1069 Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Fangrui Song <maskray@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Fixes: d812db78288d ("vmlinux.lds.h: Avoid KASAN and KCSAN's unwanted sections") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210130004650.2682422-1-nathan@kernel.org 
clang produces .eh_frame sections when CONFIG_GCOV_KERNEL is enabled,
even when -fno-asynchronous-unwind-tables is in KBUILD_CFLAGS:

$ make CC=clang vmlinux
...
ld: warning: orphan section `.eh_frame' from `init/main.o' being placed in section `.eh_frame'
ld: warning: orphan section `.eh_frame' from `init/version.o' being placed in section `.eh_frame'
ld: warning: orphan section `.eh_frame' from `init/do_mounts.o' being placed in section `.eh_frame'
ld: warning: orphan section `.eh_frame' from `init/do_mounts_initrd.o' being placed in section `.eh_frame'
ld: warning: orphan section `.eh_frame' from `init/initramfs.o' being placed in section `.eh_frame'
ld: warning: orphan section `.eh_frame' from `init/calibrate.o' being placed in section `.eh_frame'
ld: warning: orphan section `.eh_frame' from `init/init_task.o' being placed in section `.eh_frame'
...

$ rg "GCOV_KERNEL|GCOV_PROFILE_ALL" .config
CONFIG_GCOV_KERNEL=y
CONFIG_ARCH_HAS_GCOV_PROFILE_ALL=y
CONFIG_GCOV_PROFILE_ALL=y

This was already handled for a couple of other options in
commit d812db78288d ("vmlinux.lds.h: Avoid KASAN and KCSAN's unwanted
sections") and there is an open LLVM bug for this issue. Take advantage
of that section for this config as well so that there are no more orphan
warnings.

Link: https://bugs.llvm.org/show_bug.cgi?id=46478
Link: https://github.com/ClangBuiltLinux/linux/issues/1069
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Fangrui Song <maskray@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Fixes: d812db78288d ("vmlinux.lds.h: Avoid KASAN and KCSAN's unwanted sections")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210130004650.2682422-1-nathan@kernel.org
Merge tag 'mips_5.12_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux 2021-02-25T20:18:21+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-02-25T20:18:21+00:00 a6525b999970466b548d41e73d3b814233fa42ca Pull more MIPS updates from Thomas Bogendoerfer: - added n64 block driver - fix for ubsan warnings - fix for bcm63xx platform - update of linux-mips mailinglist * tag 'mips_5.12_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: arch: mips: update references to current linux-mips list mips: bmips: init clocks earlier vmlinux.lds.h: catch even more instrumentation symbols into .data n64: store dev instance into disk private data n64: cleanup n64cart_probe() n64: cosmetics changes n64: remove curly brackets n64: use sector SECTOR_SHIFT instead 512 n64: use enums for reg n64: move module param at the top n64: move module info at the end n64: use pr_fmt to avoid duplicate string block: Add n64 cart driver 
Pull more MIPS updates from Thomas Bogendoerfer:

 - added n64 block driver

 - fix for ubsan warnings

 - fix for bcm63xx platform

 - update of linux-mips mailinglist

* tag 'mips_5.12_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  arch: mips: update references to current linux-mips list
  mips: bmips: init clocks earlier
  vmlinux.lds.h: catch even more instrumentation symbols into .data
  n64: store dev instance into disk private data
  n64: cleanup n64cart_probe()
  n64: cosmetics changes
  n64: remove curly brackets
  n64: use sector SECTOR_SHIFT instead 512
  n64: use enums for reg
  n64: move module param at the top
  n64: move module info at the end
  n64: use pr_fmt to avoid duplicate string
  block: Add n64 cart driver
Merge tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild 2021-02-25T18:17:31+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-02-25T18:17:31+00:00 6fbd6cf85a3be127454a1ad58525a3adcf8612ab Pull Kbuild updates from Masahiro Yamada: - Fix false-positive build warnings for ARCH=ia64 builds - Optimize dictionary size for module compression with xz - Check the compiler and linker versions in Kconfig - Fix misuse of extra-y - Support DWARF v5 debug info - Clamp SUBLEVEL to 255 because stable releases 4.4.x and 4.9.x exceeded the limit - Add generic syscall{tbl,hdr}.sh for cleanups across arches - Minor cleanups of genksyms - Minor cleanups of Kconfig * tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (38 commits) initramfs: Remove redundant dependency of RD_ZSTD on BLK_DEV_INITRD kbuild: remove deprecated 'always' and 'hostprogs-y/m' kbuild: parse C= and M= before changing the working directory kbuild: reuse this-makefile to define abs_srctree kconfig: unify rule of config, menuconfig, nconfig, gconfig, xconfig kconfig: omit --oldaskconfig option for 'make config' kconfig: fix 'invalid option' for help option kconfig: remove dead code in conf_askvalue() kconfig: clean up nested if-conditionals in check_conf() kconfig: Remove duplicate call to sym_get_string_value() Makefile: Remove # characters from compiler string Makefile: reuse CC_VERSION_TEXT kbuild: check the minimum linker version in Kconfig kbuild: remove ld-version macro scripts: add generic syscallhdr.sh scripts: add generic syscalltbl.sh arch: syscalls: remove $(srctree)/ prefix from syscall tables arch: syscalls: add missing FORCE and fix 'targets' to make if_changed work gen_compile_commands: prune some directories kbuild: simplify access to the kernel's version ... 
Pull Kbuild updates from Masahiro Yamada:

 - Fix false-positive build warnings for ARCH=ia64 builds

 - Optimize dictionary size for module compression with xz

 - Check the compiler and linker versions in Kconfig

 - Fix misuse of extra-y

 - Support DWARF v5 debug info

 - Clamp SUBLEVEL to 255 because stable releases 4.4.x and 4.9.x
   exceeded the limit

 - Add generic syscall{tbl,hdr}.sh for cleanups across arches

 - Minor cleanups of genksyms

 - Minor cleanups of Kconfig

* tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (38 commits)
  initramfs: Remove redundant dependency of RD_ZSTD on BLK_DEV_INITRD
  kbuild: remove deprecated 'always' and 'hostprogs-y/m'
  kbuild: parse C= and M= before changing the working directory
  kbuild: reuse this-makefile to define abs_srctree
  kconfig: unify rule of config, menuconfig, nconfig, gconfig, xconfig
  kconfig: omit --oldaskconfig option for 'make config'
  kconfig: fix 'invalid option' for help option
  kconfig: remove dead code in conf_askvalue()
  kconfig: clean up nested if-conditionals in check_conf()
  kconfig: Remove duplicate call to sym_get_string_value()
  Makefile: Remove # characters from compiler string
  Makefile: reuse CC_VERSION_TEXT
  kbuild: check the minimum linker version in Kconfig
  kbuild: remove ld-version macro
  scripts: add generic syscallhdr.sh
  scripts: add generic syscalltbl.sh
  arch: syscalls: remove $(srctree)/ prefix from syscall tables
  arch: syscalls: add missing FORCE and fix 'targets' to make if_changed work
  gen_compile_commands: prune some directories
  kbuild: simplify access to the kernel's version
  ...
Merge tag 'modules-for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux 2021-02-23T18:15:33+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-02-23T18:15:33+00:00 21a6ab2131ab0644eeef70507e20273338bf065c Pull module updates from Jessica Yu: - Retire EXPORT_UNUSED_SYMBOL() and EXPORT_SYMBOL_GPL_FUTURE(). These export types were introduced between 2006 - 2008. All the of the unused symbols have been long removed and gpl future symbols were converted to gpl quite a long time ago, and I don't believe these export types have been used ever since. So, I think it should be safe to retire those export types now (Christoph Hellwig) - Refactor and clean up some aged code cruft in the module loader (Christoph Hellwig) - Build {,module_}kallsyms_on_each_symbol only when livepatching is enabled, as it is the only caller (Christoph Hellwig) - Unexport find_module() and module_mutex and fix the last module callers to not rely on these anymore. Make module_mutex internal to the module loader (Christoph Hellwig) - Harden ELF checks on module load and validate ELF structures before checking the module signature (Frank van der Linden) - Fix undefined symbol warning for clang (Fangrui Song) - Fix smatch warning (Dan Carpenter) * tag 'modules-for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: module: potential uninitialized return in module_kallsyms_on_each_symbol() module: remove EXPORT_UNUSED_SYMBOL* module: remove EXPORT_SYMBOL_GPL_FUTURE module: move struct symsearch to module.c module: pass struct find_symbol_args to find_symbol module: merge each_symbol_section into find_symbol module: remove each_symbol_in_section module: mark module_mutex static kallsyms: only build {,module_}kallsyms_on_each_symbol when required kallsyms: refactor {,module_}kallsyms_on_each_symbol module: use RCU to synchronize find_module module: unexport find_module and module_mutex drm: remove drm_fb_helper_modinit powerpc/powernv: remove get_cxl_module module: harden ELF info handling module: Ignore _GLOBAL_OFFSET_TABLE_ when warning for undefined symbols 
Pull module updates from Jessica Yu:

 - Retire EXPORT_UNUSED_SYMBOL() and EXPORT_SYMBOL_GPL_FUTURE(). These
   export types were introduced between 2006 - 2008. All the of the
   unused symbols have been long removed and gpl future symbols were
   converted to gpl quite a long time ago, and I don't believe these
   export types have been used ever since. So, I think it should be safe
   to retire those export types now (Christoph Hellwig)

 - Refactor and clean up some aged code cruft in the module loader
   (Christoph Hellwig)

 - Build {,module_}kallsyms_on_each_symbol only when livepatching is
   enabled, as it is the only caller (Christoph Hellwig)

 - Unexport find_module() and module_mutex and fix the last module
   callers to not rely on these anymore. Make module_mutex internal to
   the module loader (Christoph Hellwig)

 - Harden ELF checks on module load and validate ELF structures before
   checking the module signature (Frank van der Linden)

 - Fix undefined symbol warning for clang (Fangrui Song)

 - Fix smatch warning (Dan Carpenter)

* tag 'modules-for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: potential uninitialized return in module_kallsyms_on_each_symbol()
  module: remove EXPORT_UNUSED_SYMBOL*
  module: remove EXPORT_SYMBOL_GPL_FUTURE
  module: move struct symsearch to module.c
  module: pass struct find_symbol_args to find_symbol
  module: merge each_symbol_section into find_symbol
  module: remove each_symbol_in_section
  module: mark module_mutex static
  kallsyms: only build {,module_}kallsyms_on_each_symbol when required
  kallsyms: refactor {,module_}kallsyms_on_each_symbol
  module: use RCU to synchronize find_module
  module: unexport find_module and module_mutex
  drm: remove drm_fb_helper_modinit
  powerpc/powernv: remove get_cxl_module
  module: harden ELF info handling
  module: Ignore _GLOBAL_OFFSET_TABLE_ when warning for undefined symbols
Merge tag 'clang-lto-v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux 2021-02-23T17:28:51+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-02-23T17:28:51+00:00 79db4d2293eba2ce6265a341bedf6caecad5eeb3 Pull clang LTO updates from Kees Cook: "Clang Link Time Optimization. This is built on the work done preparing for LTO by arm64 folks, tracing folks, etc. This includes the core changes as well as the remaining pieces for arm64 (LTO has been the default build method on Android for about 3 years now, as it is the prerequisite for the Control Flow Integrity protections). While x86 LTO enablement is done, it depends on some pending objtool clean-ups. It's possible that I'll send a "part 2" pull request for LTO that includes x86 support. For merge log posterity, and as detailed in commit dc5723b02e52 ("kbuild: add support for Clang LTO"), here is the lt;dr to do an LTO build: make LLVM=1 LLVM_IAS=1 defconfig scripts/config -e LTO_CLANG_THIN make LLVM=1 LLVM_IAS=1 (To do a cross-compile of arm64, add "CROSS_COMPILE=aarch64-linux-gnu-" and "ARCH=arm64" to the "make" command lines.) Summary: - Clang LTO build infrastructure and arm64-specific enablement (Sami Tolvanen) - Recursive build CC_FLAGS_LTO fix (Alexander Lobakin)" * tag 'clang-lto-v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: kbuild: prevent CC_FLAGS_LTO self-bloating on recursive rebuilds arm64: allow LTO to be selected arm64: disable recordmcount with DYNAMIC_FTRACE_WITH_REGS arm64: vdso: disable LTO drivers/misc/lkdtm: disable LTO for rodata.o efi/libstub: disable LTO scripts/mod: disable LTO for empty.c modpost: lto: strip .lto from module names PCI: Fix PREL32 relocations for LTO init: lto: fix PREL32 relocations init: lto: ensure initcall ordering kbuild: lto: add a default list of used symbols kbuild: lto: merge module sections kbuild: lto: limit inlining kbuild: lto: fix module versioning kbuild: add support for Clang LTO tracing: move function tracer options to Kconfig 
Pull clang LTO updates from Kees Cook:
 "Clang Link Time Optimization.

  This is built on the work done preparing for LTO by arm64 folks,
  tracing folks, etc. This includes the core changes as well as the
  remaining pieces for arm64 (LTO has been the default build method on
  Android for about 3 years now, as it is the prerequisite for the
  Control Flow Integrity protections).

  While x86 LTO enablement is done, it depends on some pending objtool
  clean-ups. It's possible that I'll send a "part 2" pull request for
  LTO that includes x86 support.

  For merge log posterity, and as detailed in commit dc5723b02e52
  ("kbuild: add support for Clang LTO"), here is the lt;dr to do an LTO
  build:

        make LLVM=1 LLVM_IAS=1 defconfig
        scripts/config -e LTO_CLANG_THIN
        make LLVM=1 LLVM_IAS=1

  (To do a cross-compile of arm64, add "CROSS_COMPILE=aarch64-linux-gnu-"
  and "ARCH=arm64" to the "make" command lines.)

  Summary:

   - Clang LTO build infrastructure and arm64-specific enablement (Sami
     Tolvanen)

   - Recursive build CC_FLAGS_LTO fix (Alexander Lobakin)"

* tag 'clang-lto-v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  kbuild: prevent CC_FLAGS_LTO self-bloating on recursive rebuilds
  arm64: allow LTO to be selected
  arm64: disable recordmcount with DYNAMIC_FTRACE_WITH_REGS
  arm64: vdso: disable LTO
  drivers/misc/lkdtm: disable LTO for rodata.o
  efi/libstub: disable LTO
  scripts/mod: disable LTO for empty.c
  modpost: lto: strip .lto from module names
  PCI: Fix PREL32 relocations for LTO
  init: lto: fix PREL32 relocations
  init: lto: ensure initcall ordering
  kbuild: lto: add a default list of used symbols
  kbuild: lto: merge module sections
  kbuild: lto: limit inlining
  kbuild: lto: fix module versioning
  kbuild: add support for Clang LTO
  tracing: move function tracer options to Kconfig
vmlinux.lds.h: catch even more instrumentation symbols into .data 2021-02-23T12:23:11+00:00 Alexander Lobakin alobakin@pm.me 2021-02-23T11:36:21+00:00 49387f628840eac1e7e1113f4f2c150cdecf88c7 LKP caught another bunch of orphaned instrumentation symbols [0]: mipsel-linux-ld: warning: orphan section `.data.$LPBX1' from `init/main.o' being placed in section `.data.$LPBX1' mipsel-linux-ld: warning: orphan section `.data.$LPBX0' from `init/main.o' being placed in section `.data.$LPBX0' mipsel-linux-ld: warning: orphan section `.data.$LPBX1' from `init/do_mounts.o' being placed in section `.data.$LPBX1' mipsel-linux-ld: warning: orphan section `.data.$LPBX0' from `init/do_mounts.o' being placed in section `.data.$LPBX0' mipsel-linux-ld: warning: orphan section `.data.$LPBX1' from `init/do_mounts_initrd.o' being placed in section `.data.$LPBX1' mipsel-linux-ld: warning: orphan section `.data.$LPBX0' from `init/do_mounts_initrd.o' being placed in section `.data.$LPBX0' mipsel-linux-ld: warning: orphan section `.data.$LPBX1' from `init/initramfs.o' being placed in section `.data.$LPBX1' mipsel-linux-ld: warning: orphan section `.data.$LPBX0' from `init/initramfs.o' being placed in section `.data.$LPBX0' mipsel-linux-ld: warning: orphan section `.data.$LPBX1' from `init/calibrate.o' being placed in section `.data.$LPBX1' mipsel-linux-ld: warning: orphan section `.data.$LPBX0' from `init/calibrate.o' being placed in section `.data.$LPBX0' [...] Soften the wildcard to .data.$L* to grab these ones into .data too. [0] https://lore.kernel.org/lkml/202102231519.lWPLPveV-lkp@intel.com Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Alexander Lobakin <alobakin@pm.me> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> 
LKP caught another bunch of orphaned instrumentation symbols [0]:

mipsel-linux-ld: warning: orphan section `.data.$LPBX1' from
`init/main.o' being placed in section `.data.$LPBX1'
mipsel-linux-ld: warning: orphan section `.data.$LPBX0' from
`init/main.o' being placed in section `.data.$LPBX0'
mipsel-linux-ld: warning: orphan section `.data.$LPBX1' from
`init/do_mounts.o' being placed in section `.data.$LPBX1'
mipsel-linux-ld: warning: orphan section `.data.$LPBX0' from
`init/do_mounts.o' being placed in section `.data.$LPBX0'
mipsel-linux-ld: warning: orphan section `.data.$LPBX1' from
`init/do_mounts_initrd.o' being placed in section `.data.$LPBX1'
mipsel-linux-ld: warning: orphan section `.data.$LPBX0' from
`init/do_mounts_initrd.o' being placed in section `.data.$LPBX0'
mipsel-linux-ld: warning: orphan section `.data.$LPBX1' from
`init/initramfs.o' being placed in section `.data.$LPBX1'
mipsel-linux-ld: warning: orphan section `.data.$LPBX0' from
`init/initramfs.o' being placed in section `.data.$LPBX0'
mipsel-linux-ld: warning: orphan section `.data.$LPBX1' from
`init/calibrate.o' being placed in section `.data.$LPBX1'
mipsel-linux-ld: warning: orphan section `.data.$LPBX0' from
`init/calibrate.o' being placed in section `.data.$LPBX0'

[...]

Soften the wildcard to .data.$L* to grab these ones into .data too.

[0] https://lore.kernel.org/lkml/202102231519.lWPLPveV-lkp@intel.com

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Merge tag 'mips_5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux 2021-02-21T21:18:26+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-02-21T21:18:26+00:00 2671fe5e1d48fe2c14a46bdf8fd9d7b24f88c1e2 Pull MIPS updates from Thomas Bogendoerfer: - added support for Nintendo N64 - added support for Realtek RTL83XX SoCs - kaslr support for Loongson64 - first steps to get rid of set_fs() - DMA runtime coherent/non-coherent selection cleanup - cleanups and fixes * tag 'mips_5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (98 commits) Revert "MIPS: Add basic support for ptrace single step" vmlinux.lds.h: catch more UBSAN symbols into .data MIPS: kernel: Drop kgdb_call_nmi_hook MAINTAINERS: Add git tree for KVM/mips MIPS: Use common way to parse elfcorehdr MIPS: Simplify EVA cache handling Revert "MIPS: kernel: {ftrace,kgdb}: Set correct address limit for cache flushes" MIPS: remove CONFIG_DMA_PERDEV_COHERENT MIPS: remove CONFIG_DMA_MAYBE_COHERENT driver core: lift dma_default_coherent into common code MIPS: refactor the runtime coherent vs noncoherent DMA indicators MIPS/alchemy: factor out the DMA coherent setup MIPS/malta: simplify plat_setup_iocoherency MIPS: Add basic support for ptrace single step MAINTAINERS: replace non-matching patterns for loongson{2,3} MIPS: Make check condition for SDBBP consistent with EJTAG spec mips: Replace lkml.org links with lore Revert "MIPS: microMIPS: Fix the judgment of mm_jr16_op and mm_jalr_op" MIPS: crash_dump.c: Simplify copy_oldmem_page() Revert "mips: Manually call fdt_init_reserved_mem() method" ... 
Pull MIPS updates from Thomas Bogendoerfer:

 - added support for Nintendo N64

 - added support for Realtek RTL83XX SoCs

 - kaslr support for Loongson64

 - first steps to get rid of set_fs()

 - DMA runtime coherent/non-coherent selection cleanup

 - cleanups and fixes

* tag 'mips_5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (98 commits)
  Revert "MIPS: Add basic support for ptrace single step"
  vmlinux.lds.h: catch more UBSAN symbols into .data
  MIPS: kernel: Drop kgdb_call_nmi_hook
  MAINTAINERS: Add git tree for KVM/mips
  MIPS: Use common way to parse elfcorehdr
  MIPS: Simplify EVA cache handling
  Revert "MIPS: kernel: {ftrace,kgdb}: Set correct address limit for cache flushes"
  MIPS: remove CONFIG_DMA_PERDEV_COHERENT
  MIPS: remove CONFIG_DMA_MAYBE_COHERENT
  driver core: lift dma_default_coherent into common code
  MIPS: refactor the runtime coherent vs noncoherent DMA indicators
  MIPS/alchemy: factor out the DMA coherent setup
  MIPS/malta: simplify plat_setup_iocoherency
  MIPS: Add basic support for ptrace single step
  MAINTAINERS: replace non-matching patterns for loongson{2,3}
  MIPS: Make check condition for SDBBP consistent with EJTAG spec
  mips: Replace lkml.org links with lore
  Revert "MIPS: microMIPS: Fix the judgment of mm_jr16_op and mm_jalr_op"
  MIPS: crash_dump.c: Simplify copy_oldmem_page()
  Revert "mips: Manually call fdt_init_reserved_mem() method"
  ...