Changes in 5.15.57
x86/traps: Use pt_regs directly in fixup_bad_iret()
x86/entry: Switch the stack after error_entry() returns
x86/entry: Move PUSH_AND_CLEAR_REGS out of error_entry()
x86/entry: Don't call error_entry() for XENPV
objtool: Classify symbols
objtool: Explicitly avoid self modifying code in .altinstr_replacement
objtool: Shrink struct instruction
objtool,x86: Replace alternatives with .retpoline_sites
objtool: Introduce CFI hash
x86/retpoline: Remove unused replacement symbols
x86/asm: Fix register order
x86/asm: Fixup odd GEN-for-each-reg.h usage
x86/retpoline: Move the retpoline thunk declarations to nospec-branch.h
x86/retpoline: Create a retpoline thunk array
x86/alternative: Implement .retpoline_sites support
x86/alternative: Handle Jcc __x86_indirect_thunk_\reg
x86/alternative: Try inline spectre_v2=retpoline,amd
x86/alternative: Add debug prints to apply_retpolines()
bpf,x86: Simplify computing label offsets
bpf,x86: Respect X86_FEATURE_RETPOLINE*
objtool: Default ignore INT3 for unreachable
x86/entry: Remove skip_r11rcx
x86/realmode: build with -D__DISABLE_EXPORTS
x86/kvm/vmx: Make noinstr clean
x86/cpufeatures: Move RETPOLINE flags to word 11
x86/retpoline: Cleanup some #ifdefery
x86/retpoline: Swizzle retpoline thunk
x86/retpoline: Use -mfunction-return
x86: Undo return-thunk damage
x86,objtool: Create .return_sites
objtool: skip non-text sections when adding return-thunk sites
x86,static_call: Use alternative RET encoding
x86/ftrace: Use alternative RET encoding
x86/bpf: Use alternative RET encoding
x86/kvm: Fix SETcc emulation for return thunks
x86/vsyscall_emu/64: Don't use RET in vsyscall emulation
x86/sev: Avoid using __x86_return_thunk
x86: Use return-thunk in asm code
x86/entry: Avoid very early RET
objtool: Treat .text.__x86.* as noinstr
x86: Add magic AMD return-thunk
x86/bugs: Report AMD retbleed vulnerability
x86/bugs: Add AMD retbleed= boot parameter
x86/bugs: Enable STIBP for JMP2RET
x86/bugs: Keep a per-CPU IA32_SPEC_CTRL value
x86/entry: Add kernel IBRS implementation
x86/bugs: Optimize SPEC_CTRL MSR writes
x86/speculation: Add spectre_v2=ibrs option to support Kernel IBRS
x86/bugs: Split spectre_v2_select_mitigation() and spectre_v2_user_select_mitigation()
x86/bugs: Report Intel retbleed vulnerability
intel_idle: Disable IBRS during long idle
objtool: Update Retpoline validation
x86/xen: Rename SYS* entry points
x86/xen: Add UNTRAIN_RET
x86/bugs: Add retbleed=ibpb
x86/bugs: Do IBPB fallback check only once
objtool: Add entry UNRET validation
x86/cpu/amd: Add Spectral Chicken
x86/speculation: Fix RSB filling with CONFIG_RETPOLINE=n
x86/speculation: Fix firmware entry SPEC_CTRL handling
x86/speculation: Fix SPEC_CTRL write on SMT state change
x86/speculation: Use cached host SPEC_CTRL value for guest entry/exit
x86/speculation: Remove x86_spec_ctrl_mask
objtool: Re-add UNWIND_HINT_{SAVE_RESTORE}
KVM: VMX: Flatten __vmx_vcpu_run()
KVM: VMX: Convert launched argument to flags
KVM: VMX: Prevent guest RSB poisoning attacks with eIBRS
KVM: VMX: Fix IBRS handling after vmexit
x86/speculation: Fill RSB on vmexit for IBRS
x86/common: Stamp out the stepping madness
x86/cpu/amd: Enumerate BTC_NO
x86/retbleed: Add fine grained Kconfig knobs
x86/bugs: Add Cannon lake to RETBleed affected CPU list
x86/entry: Move PUSH_AND_CLEAR_REGS() back into error_entry
x86/bugs: Do not enable IBPB-on-entry when IBPB is not supported
x86/kexec: Disable RET on kexec
x86/speculation: Disable RRSBA behavior
x86/static_call: Serialize __static_call_fixup() properly
x86/xen: Fix initialisation in hypercall_page after rethunk
x86/asm/32: Fix ANNOTATE_UNRET_SAFE use on 32-bit
x86/speculation: Use DECLARE_PER_CPU for x86_spec_ctrl_current
efi/x86: use naked RET on mixed mode call wrapper
x86/kvm: fix FASTOP_SIZE when return thunks are enabled
KVM: emulate: do not adjust size of fastop and setcc subroutines
tools arch x86: Sync the msr-index.h copy with the kernel sources
tools headers cpufeatures: Sync with the kernel sources
x86/bugs: Remove apostrophe typo
um: Add missing apply_returns()
x86: Use -mindirect-branch-cs-prefix for RETPOLINE builds
Linux 5.15.57
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I41605a6dc38163a964d921f2d4ec8a1a316a5cbc
Commit 156ff4a544ae ("x86/ibt: Base IBT bits") added this option when
building realmode in order to disable IBT there. This is also needed in
order to disable return thunks.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Steps on the way to 5.15-rc1
Fixed up merge conflicts in:
scripts/Makefile.modfinal
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I3a916b7267fc2e4ed2f2bd308b9cff8ca9430660
Pull Kbuild updates from Masahiro Yamada:
- Add -s option (strict mode) to merge_config.sh to make it fail when
any symbol is redefined.
- Show a warning if a different compiler is used for building external
modules.
- Infer --target from ARCH for CC=clang to let you cross-compile the
kernel without CROSS_COMPILE.
- Make the integrated assembler default (LLVM_IAS=1) for CC=clang.
- Add <linux/stdarg.h> to the kernel source instead of borrowing
<stdarg.h> from the compiler.
- Add Nick Desaulniers as a Kbuild reviewer.
- Drop stale cc-option tests.
- Fix the combination of CONFIG_TRIM_UNUSED_KSYMS and CONFIG_LTO_CLANG
to handle symbols in inline assembly.
- Show a warning if 'FORCE' is missing for if_changed rules.
- Various cleanups
* tag 'kbuild-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (39 commits)
kbuild: redo fake deps at include/ksym/*.h
kbuild: clean up objtool_args slightly
modpost: get the *.mod file path more simply
checkkconfigsymbols.py: Fix the '--ignore' option
kbuild: merge vmlinux_link() between ARCH=um and other architectures
kbuild: do not remove 'linux' link in scripts/link-vmlinux.sh
kbuild: merge vmlinux_link() between the ordinary link and Clang LTO
kbuild: remove stale *.symversions
kbuild: remove unused quiet_cmd_update_lto_symversions
gen_compile_commands: extract compiler command from a series of commands
x86: remove cc-option-yn test for -mtune=
arc: replace cc-option-yn uses with cc-option
s390: replace cc-option-yn uses with cc-option
ia64: move core-y in arch/ia64/Makefile to arch/ia64/Kbuild
sparc: move the install rule to arch/sparc/Makefile
security: remove unneeded subdir-$(CONFIG_...)
kbuild: sh: remove unused install script
kbuild: Fix 'no symbols' warning when CONFIG_TRIM_UNUSD_KSYMS=y
kbuild: Switch to 'f' variants of integrated assembler flag
kbuild: Shuffle blank line to improve comment meaning
...
cc-option, __cc-option, cc-option-yn, and cc-disable-warning all invoke
the compiler during build time, and can slow down the build when these
checks become stale for our supported compilers, whose minimally
supported versions increases over time.
See Documentation/process/changes.rst for the current supported minimal
versions (GCC 4.9+, clang 10.0.1+). Compiler version support for these
flags may be verified on godbolt.org.
The following flags are supported by all supported versions of GCC and
Clang. Remove their cc-option, __cc-option, and cc-option-yn tests.
-Wno-address-of-packed-member
-mno-avx
-m32
-mno-80387
-march=k8
-march=nocona
-march=core2
-march=atom
-mtune=generic
-mfentry
[ mingo: Fixed regression on GCC, via partial revert of the stack-boundary changes. ]
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://github.com/ClangBuiltLinux/linux/issues/1436
Link: https://lkml.kernel.org/r/20210812183848.1519994-1-ndesaulniers@google.com
As explained in commit 3204a7fb98 ("kbuild: prefix $(srctree)/ to some
included Makefiles"), I want to stop using --include-dir some day.
I already fixed up the top Makefile, but some arch Makefiles (mips, um,
x86) still include check-in Makefiles without $(srctree)/.
Fix them up so 'need-sub-make := 1' can go away for this case.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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 $(call cmd,) for generating include/generated/compile.h
kbuild: merge scripts/mkmakefile to top Makefile
sh: move core-y in arch/sh/Makefile to arch/sh/Kbuild
...
Pull x86 boot update from Ingo Molnar:
"Modernize the genimage.sh script, add a 'hdimage' target and EFI
support"
* tag 'x86-boot-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Modernize genimage script; hdimage+EFI support
Since LLVM commit 3787ee4, the '-stack-alignment' flag has been dropped
[1], leading to the following error message when building a LTO kernel
with Clang-13 and LLD-13:
ld.lld: error: -plugin-opt=-: ld.lld: Unknown command line argument
'-stack-alignment=8'. Try 'ld.lld --help'
ld.lld: Did you mean '--stackrealign=8'?
It also appears that the '-code-model' flag is not necessary anymore
starting with LLVM-9 [2].
Drop '-code-model' and make '-stack-alignment' conditional on LLD < 13.0.0.
These flags were necessary because these flags were not encoded in the
IR properly, so the link would restart optimizations without them. Now
there are properly encoded in the IR, and these flags exposing
implementation details are no longer necessary.
[1] https://reviews.llvm.org/D103048
[2] https://reviews.llvm.org/D52322
Cc: stable@vger.kernel.org
Link: https://github.com/ClangBuiltLinux/linux/issues/1377
Signed-off-by: Tor Vic <torvic9@mailbox.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/f2c018ee-5999-741e-58d4-e482d5246067@mailbox.org
arch/$(SRCARCH)/Kbuild is useful for Makefile cleanups because you can
use the obj-y syntax.
Add an empty file if it is missing in arch/$(SRCARCH)/.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
When KBUILD_MIXED_TREE is set, vmlinux and related images come from an
out-of-tree location and vmlinux shouldn't be compiled. arch/arm64 and
arch/x86 add the default Images to all target, so remove that default
behavior when KBUILD_MIXED_TREE is set.
This when an out-of-tree module, e.g. virtual-device, runs "make all"
instead of "make modules".
Bug: 178469391
Change-Id: I8c43d5d66a8bf6ed27f91df7e173399d4f4a23c0
Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>
Commit b33fff07e3 ("x86, build: allow LTO to be selected") added a
couple of '-plugin-opt=' flags to KBUILD_LDFLAGS because the code model
and stack alignment are not stored in LLVM bitcode.
However, these flags were added to KBUILD_LDFLAGS prior to the
emulation flag assignment, which uses ':=', so they were overwritten
and never added to $(LD) invocations.
The absence of these flags caused misalignment issues in the
AMDGPU driver when compiling with CONFIG_LTO_CLANG, resulting in
general protection faults.
Shuffle the assignment below the initial one so that the flags are
properly passed along and all of the linker flags stay together.
At the same time, avoid any future issues with clobbering flags by
changing the emulation flag assignment to '+=' since KBUILD_LDFLAGS is
already defined with ':=' in the main Makefile before being exported for
modification here as a result of commit:
ce99d0bf31 ("kbuild: clear LDFLAGS in the top Makefile")
Fixes: b33fff07e3 ("x86, build: allow LTO to be selected")
Reported-by: Anthony Ruhier <aruhier@mailbox.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Anthony Ruhier <aruhier@mailbox.org>
Cc: stable@vger.kernel.org
Link: https://github.com/ClangBuiltLinux/linux/issues/1374
Link: https://lore.kernel.org/r/20210518190106.60935-1-nathan@kernel.org
The image generation scripts in arch/x86/boot are pretty out of date,
except for the isoimage target. Update and clean up the
genimage.sh script, and make it support an arbitrary number of
initramfs files in the image.
Add a "hdimage" target, which can be booted by either BIOS or
EFI (if the kernel is compiled with the EFI stub.) For EFI to be able
to pass the command line to the kernel, we need the EFI shell, but the
firmware builtin EFI shell, if it even exists, is pretty much always
the last resort boot option, so search for OVMF or EDK2 and explicitly
include a copy of the EFI shell.
To make this all work, use bash features in the script. Furthermore,
this version of the script makes use of some mtools features,
especially mpartition, that might not exist in very old version of
mtools, but given all the other dependencies on this script this
doesn't seem such a big deal.
Finally, put a volume label ("LINUX_BOOT") on all generated images.
Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210510082840.628372-1-hpa@zytor.com
Pull Kbuild updates from Masahiro Yamada:
- Evaluate $(call cc-option,...) etc. only for build targets
- Add CONFIG_VMLINUX_MAP to generate .map file when linking vmlinux
- Remove unnecessary --gcc-toolchains Clang flag because the --prefix
flag finds the toolchains
- Do not pass Clang's --prefix flag when using the integrated as
- Check the assembler version in Kconfig time
- Add new CONFIG options, AS_VERSION, AS_IS_GNU, AS_IS_LLVM to clean up
some dependencies in Kconfig
- Fix invalid Module.symvers creation when building only modules
without vmlinux
- Fix false-positive modpost warnings when CONFIG_TRIM_UNUSED_KSYMS is
set, but there is no module to build
- Refactor module installation Makefile
- Support zstd for module compression
- Convert alpha and ia64 to use generic shell scripts to generate the
syscall headers
- Add a new elfnote to indicate if the kernel was built with LTO, which
will be used by pahole
- Flatten the directory structure under include/config/ so CONFIG
options and filenames match
- Change the deb source package name from linux-$(KERNELRELEASE) to
linux-upstream
* tag 'kbuild-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (42 commits)
kbuild: Add $(KBUILD_HOSTLDFLAGS) to 'has_libelf' test
kbuild: deb-pkg: change the source package name to linux-upstream
tools: do not include scripts/Kbuild.include
kbuild: redo fake deps at include/config/*.h
kbuild: remove TMPO from try-run
MAINTAINERS: add pattern for dummy-tools
kbuild: add an elfnote for whether vmlinux is built with lto
ia64: syscalls: switch to generic syscallhdr.sh
ia64: syscalls: switch to generic syscalltbl.sh
alpha: syscalls: switch to generic syscallhdr.sh
alpha: syscalls: switch to generic syscalltbl.sh
sysctl: use min() helper for namecmp()
kbuild: add support for zstd compressed modules
kbuild: remove CONFIG_MODULE_COMPRESS
kbuild: merge scripts/Makefile.modsign to scripts/Makefile.modinst
kbuild: move module strip/compression code into scripts/Makefile.modinst
kbuild: refactor scripts/Makefile.modinst
kbuild: rename extmod-prefix to extmod_prefix
kbuild: check module name conflict for external modules as well
kbuild: show the target directory for depmod log
...
Pull x86 updates from Borislav Petkov:
- Turn the stack canary into a normal __percpu variable on 32-bit which
gets rid of the LAZY_GS stuff and a lot of code.
- Add an insn_decode() API which all users of the instruction decoder
should preferrably use. Its goal is to keep the details of the
instruction decoder away from its users and simplify and streamline
how one decodes insns in the kernel. Convert its users to it.
- kprobes improvements and fixes
- Set the maximum DIE per package variable on Hygon
- Rip out the dynamic NOP selection and simplify all the machinery
around selecting NOPs. Use the simplified NOPs in objtool now too.
- Add Xeon Sapphire Rapids to list of CPUs that support PPIN
- Simplify the retpolines by folding the entire thing into an
alternative now that objtool can handle alternatives with stack ops.
Then, have objtool rewrite the call to the retpoline with the
alternative which then will get patched at boot time.
- Document Intel uarch per models in intel-family.h
- Make Sub-NUMA Clustering topology the default and Cluster-on-Die the
exception on Intel.
* tag 'x86_core_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
x86, sched: Treat Intel SNC topology as default, COD as exception
x86/cpu: Comment Skylake server stepping too
x86/cpu: Resort and comment Intel models
objtool/x86: Rewrite retpoline thunk calls
objtool: Skip magical retpoline .altinstr_replacement
objtool: Cache instruction relocs
objtool: Keep track of retpoline call sites
objtool: Add elf_create_undef_symbol()
objtool: Extract elf_symbol_add()
objtool: Extract elf_strtab_concat()
objtool: Create reloc sections implicitly
objtool: Add elf_create_reloc() helper
objtool: Rework the elf_rebuild_reloc_section() logic
objtool: Fix static_call list generation
objtool: Handle per arch retpoline naming
objtool: Correctly handle retpoline thunk calls
x86/retpoline: Simplify retpolines
x86/alternatives: Optimize optimize_nops()
x86: Add insn_decode_kernel()
x86/kprobes: Move 'inline' to the beginning of the kprobe_is_ss() declaration
...
Pull x86 build updates from Borislav Petkov:
"A bunch of clang build fixes and a Kconfig highmem selection fix for
486SX"
* tag 'x86_build_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/build: Disable HIGHMEM64G selection for M486SX
efi/libstub: Add $(CLANG_FLAGS) to x86 flags
x86/boot: Add $(CLANG_FLAGS) to compressed KBUILD_CFLAGS
x86/build: Propagate $(CLANG_FLAGS) to $(REALMODE_FLAGS)
TMPO is only used by arch/x86/Makefile.
Change arch/x86/Makefile to use $$TMPO.o and remove TMPO from
scripts/Makefile.compiler.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
In particular we want to have this upstream commit:
b908297047: ("bpf: Use NOP_ATOMIC5 instead of emit_nops(&prog, 5) for BPF_TRAMP_F_CALL_ORIG")
... before merging in x86/cpu changes and the removal of the NOP optimizations, and
applying PeterZ's !retpoline objtool series.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When cross-compiling with Clang, the `$(CLANG_FLAGS)' variable
contains additional flags needed to build C and assembly sources
for the target platform. Normally this variable is automatically
included in `$(KBUILD_CFLAGS)' via the top-level Makefile.
The x86 real-mode makefile builds `$(REALMODE_CFLAGS)' from a
plain assignment and therefore drops the Clang flags. This causes
Clang to not recognize x86-specific assembler directives:
arch/x86/realmode/rm/header.S:36:1: error: unknown directive
.type real_mode_header STT_OBJECT ; .size real_mode_header, .-real_mode_header
^
Explicit propagation of `$(CLANG_FLAGS)' to `$(REALMODE_CFLAGS)',
which is inherited by real-mode make rules, fixes cross-compilation
with Clang for x86 targets.
Relevant flags:
* `--target' sets the target architecture when cross-compiling. This
flag must be set for both compilation and assembly (`KBUILD_AFLAGS')
to support architecture-specific assembler directives.
* `-no-integrated-as' tells clang to assemble with GNU Assembler
instead of its built-in LLVM assembler. This flag is set by default
unless `LLVM_IAS=1' is set, because the LLVM assembler can't yet
parse certain GNU extensions.
Signed-off-by: John Millikin <john@john-millikin.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Link: https://lkml.kernel.org/r/20210326000435.4785-2-nathan@kernel.org
The new Ubuntu GCC packages turn on -fcf-protection globally,
which causes a build failure in the x86 realmode code:
cc1: error: ‘-fcf-protection’ is not compatible with this target
Turn it off explicitly on compilers that understand this option.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210323124846.1584944-1-arnd@kernel.org
On 32-bit kernels, the stackprotector canary is quite nasty -- it is
stored at %gs:(20), which is nasty because 32-bit kernels use %fs for
percpu storage. It's even nastier because it means that whether %gs
contains userspace state or kernel state while running kernel code
depends on whether stackprotector is enabled (this is
CONFIG_X86_32_LAZY_GS), and this setting radically changes the way
that segment selectors work. Supporting both variants is a
maintenance and testing mess.
Merely rearranging so that percpu and the stack canary
share the same segment would be messy as the 32-bit percpu address
layout isn't currently compatible with putting a variable at a fixed
offset.
Fortunately, GCC 8.1 added options that allow the stack canary to be
accessed as %fs:__stack_chk_guard, effectively turning it into an ordinary
percpu variable. This lets us get rid of all of the code to manage the
stack canary GDT descriptor and the CONFIG_X86_32_LAZY_GS mess.
(That name is special. We could use any symbol we want for the
%fs-relative mode, but for CONFIG_SMP=n, gcc refuses to let us use any
name other than __stack_chk_guard.)
Forcibly disable stackprotector on older compilers that don't support
the new options and turn the stack canary into a percpu variable. The
"lazy GS" approach is now used for all 32-bit configurations.
Also makes load_gs_index() work on 32-bit kernels. On 64-bit kernels,
it loads the GS selector and updates the user GSBASE accordingly. (This
is unchanged.) On 32-bit kernels, it loads the GS selector and updates
GSBASE, which is now always the user base. This means that the overall
effect is the same on 32-bit and 64-bit, which avoids some ifdeffery.
[ bp: Massage commit message. ]
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/c0ff7dba14041c7e5d1cae5d4df052f03759bef3.1613243844.git.luto@kernel.org
Pull more clang LTO updates from Kees Cook:
"Clang LTO x86 enablement.
Full disclosure: while this has _not_ been in linux-next (since it
initially looked like the objtool dependencies weren't going to make
v5.12), it has been under daily build and runtime testing by Sami for
quite some time. These x86 portions have been discussed on lkml, with
Peter, Josh, and others helping nail things down.
The bulk of the changes are to get objtool working happily. The rest
of the x86 enablement is very small.
Summary:
- Generate __mcount_loc in objtool (Peter Zijlstra)
- Support running objtool against vmlinux.o (Sami Tolvanen)
- Clang LTO enablement for x86 (Sami Tolvanen)"
Link: https://lore.kernel.org/lkml/20201013003203.4168817-26-samitolvanen@google.com/
Link: https://lore.kernel.org/lkml/cover.1611263461.git.jpoimboe@redhat.com/
* tag 'clang-lto-v5.12-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
kbuild: lto: force rebuilds when switching CONFIG_LTO
x86, build: allow LTO to be selected
x86, cpu: disable LTO for cpu.c
x86, vdso: disable LTO only for vDSO
kbuild: lto: postpone objtool
objtool: Split noinstr validation from --vmlinux
x86, build: use objtool mcount
tracing: add support for objtool mcount
objtool: Don't autodetect vmlinux.o
objtool: Fix __mcount_loc generation with Clang's assembler
objtool: Add a pass for generating __mcount_loc
Pass code model and stack alignment to the linker as these are not
stored in LLVM bitcode, and allow CONFIG_LTO_CLANG* to be enabled.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Pull oprofile and dcookies removal from Viresh Kumar:
"Remove oprofile and dcookies support
The 'oprofile' user-space tools don't use the kernel OPROFILE support
any more, and haven't in a long time. User-space has been converted to
the perf interfaces.
The dcookies stuff is only used by the oprofile code. Now that
oprofile's support is getting removed from the kernel, there is no
need for dcookies as well.
Remove kernel's old oprofile and dcookies support"
* tag 'oprofile-removal-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/linux:
fs: Remove dcookies support
drivers: Remove CONFIG_OPROFILE support
arch: xtensa: Remove CONFIG_OPROFILE support
arch: x86: Remove CONFIG_OPROFILE support
arch: sparc: Remove CONFIG_OPROFILE support
arch: sh: Remove CONFIG_OPROFILE support
arch: s390: Remove CONFIG_OPROFILE support
arch: powerpc: Remove oprofile
arch: powerpc: Stop building and using oprofile
arch: parisc: Remove CONFIG_OPROFILE support
arch: mips: Remove CONFIG_OPROFILE support
arch: microblaze: Remove CONFIG_OPROFILE support
arch: ia64: Remove rest of perfmon support
arch: ia64: Remove CONFIG_OPROFILE support
arch: hexagon: Don't select HAVE_OPROFILE
arch: arc: Remove CONFIG_OPROFILE support
arch: arm: Remove CONFIG_OPROFILE support
arch: alpha: Remove CONFIG_OPROFILE support
Pull x86 build updates from Borislav Petkov:
- Treat R_386_PLT32 relocations like R_386_PC32 ones when building
- Add documentation about "make kvm_guest/xen.config" in "make help"
output
* tag 'x86_build_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/build: Treat R_386_PLT32 relocation as R_386_PC32
x86/build: Realign archhelp
x86/build: Add {kvm_guest,xen}.config targets to make help's output
With retpolines disabled, some configurations of GCC, and specifically
the GCC versions 9 and 10 in Ubuntu will add Intel CET instrumentation
to the kernel by default. That breaks certain tracing scenarios by
adding a superfluous ENDBR64 instruction before the fentry call, for
functions which can be called indirectly.
CET instrumentation isn't currently necessary in the kernel, as CET is
only supported in user space. Disable it unconditionally and move it
into the x86's Makefile as CET/CFI... enablement should be a per-arch
decision anyway.
[ bp: Massage and extend commit message. ]
Fixes: 29be86d7f9 ("kbuild: add -fcf-protection=none when using retpoline flags")
Reported-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Cc: <stable@vger.kernel.org>
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Link: https://lkml.kernel.org/r/20210128215219.6kct3h2eiustncws@treble
Add the targets which add additional items to the .config which
facilitate running the kernel as a guest, to the 'make help' output so
that they can be found easier and there's no need to grep the tree each
time to remember what they should be called.
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201217134608.31811-1-bp@alien8.de
Pull x86 build updates from Borislav Petkov:
"Two x86 build fixes:
- Fix the vmlinux size check on 64-bit along with adding useful
clarifications on the topic (Arvind Sankar)
- Remove -m16 workaround now that the GCC versions that need it are
unsupported (Nick Desaulniers)"
* tag 'x86_build_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/build: Remove -m16 workaround for unsupported versions of GCC
x86/build: Fix vmlinux size check on 64-bit
Currently, '--orphan-handling=warn' is spread out across four different
architectures in their respective Makefiles, which makes it a little
unruly to deal with in case it needs to be disabled for a specific
linker version (in this case, ld.lld 10.0.1).
To make it easier to control this, hoist this warning into Kconfig and
the main Makefile so that disabling it is simpler, as the warning will
only be enabled in a couple places (main Makefile and a couple of
compressed boot folders that blow away LDFLAGS_vmlinx) and making it
conditional is easier due to Kconfig syntax. One small additional
benefit of this is saving a call to ld-option on incremental builds
because we will have already evaluated it for CONFIG_LD_ORPHAN_WARN.
To keep the list of supported architectures the same, introduce
CONFIG_ARCH_WANT_LD_ORPHAN_WARN, which an architecture can select to
gain this automatically after all of the sections are specified and size
asserted. A special thanks to Kees Cook for the help text on this
config.
Link: https://github.com/ClangBuiltLinux/linux/issues/1187
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull Kbuild updates from Masahiro Yamada:
- run the checker (e.g. sparse) after the compiler
- remove unneeded cc-option tests for old compiler flags
- fix tar-pkg to install dtbs
- introduce ccflags-remove-y and asflags-remove-y syntax
- allow to trace functions in sub-directories of lib/
- introduce hostprogs-always-y and userprogs-always-y syntax
- various Makefile cleanups
* tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: stop filtering out $(GCC_PLUGINS_CFLAGS) from cc-option base
kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled
kbuild: introduce hostprogs-always-y and userprogs-always-y
kbuild: sort hostprogs before passing it to ifneq
kbuild: move host .so build rules to scripts/gcc-plugins/Makefile
kbuild: Replace HTTP links with HTTPS ones
kbuild: trace functions in subdirectories of lib/
kbuild: introduce ccflags-remove-y and asflags-remove-y
kbuild: do not export LDFLAGS_vmlinux
kbuild: always create directories of targets
powerpc/boot: add DTB to 'targets'
kbuild: buildtar: add dtbs support
kbuild: remove cc-option test of -ffreestanding
kbuild: remove cc-option test of -fno-stack-protector
Revert "kbuild: Create directory for target DTB"
kbuild: run the checker after the compiler
This option is only required for vmlinux on 64-bit, to enforce 2MiB
alignment, so set it in LDFLAGS_vmlinux instead of KBUILD_LDFLAGS. Also
drop the ld-option check: this option was added in binutils-2.18 and all
the other places that use it already don't have the check.
This reduces the size of the intermediate ELF files
arch/x86/boot/setup.elf and arch/x86/realmode/rm/realmode.elf by about
2MiB each. The binary versions are unchanged.
Move the LDFLAGS settings to all be together and just after CFLAGS
settings are done.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Link: https://lore.kernel.org/r/20200722184334.3785418-1-nivedita@alum.mit.edu
Some Makefiles already pass -ffreestanding unconditionally.
For example, arch/arm64/lib/Makefile, arch/x86/purgatory/Makefile.
No problem report so far about hard-coding this option. So, we can
assume all supported compilers know -ffreestanding.
I confirmed GCC 4.8 and Clang manuals document this option.
Get rid of cc-option from -ffreestanding.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Some Makefiles already pass -fno-stack-protector unconditionally.
For example, arch/arm64/kernel/vdso/Makefile, arch/x86/xen/Makefile.
No problem report so far about hard-coding this option. So, we can
assume all supported compilers know -fno-stack-protector.
GCC 4.8 and Clang support this option (https://godbolt.org/z/_HDGzN)
Get rid of cc-option from -fno-stack-protector.
Remove CONFIG_CC_HAS_STACKPROTECTOR_NONE, which is always 'y'.
Note:
arch/mips/vdso/Makefile adds -fno-stack-protector twice, first
unconditionally, and second conditionally. I removed the second one.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
bzlilo is an installation target because it copies files to
$(INSTALL_PATH)/, then runs 'lilo'. However, arch/x86/Makefile and
arch/x86/boot/Makefile have it depend on vmlinux and $(obj)/bzImage,
respectively.
'make bzlilo' may update some build artifacts in the source tree.
As commit
19514fc665 ("arm, kbuild: make "make install" not depend on vmlinux")
explained, this should not happen.
Make 'bzlilo' not depend on any build artifact.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200215063852.8298-1-masahiroy@kernel.org
Doing this probing inside of the Makefiles means we have a maze of
ifdefs inside the source code and child Makefiles that need to make
proper decisions on this too. Instead, we do it at Kconfig time, like
many other compiler and assembler options, which allows us to set up the
dependencies normally for full compilation units. In the process, the
ADX test changes to use %eax instead of %r10 so that it's valid in both
32-bit and 64-bit mode.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
CONFIG_AS_AVX was introduced by commit ea4d26ae24 ("raid5: add AVX
optimized RAID5 checksumming").
We raise the minimal supported binutils version from time to time.
The last bump was commit 1fb12b35e5 ("kbuild: Raise the minimum
required binutils version to 2.21").
I confirmed the code in $(call as-instr,...) can be assembled by the
binutils 2.21 assembler and also by LLVM integrated assembler.
Remove CONFIG_AS_AVX, which is always defined.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
