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 module sections only when using Clang LTO. With ld.bfd, merging
sections does not appear to update the symbol tables for the module,
e.g. 'readelf -s' shows the value that a symbol would have had, if
sections were not merged. ld.lld does not show this problem.
The stale symbol table breaks gdb's function disassembler, and presumably
other things, e.g.
gdb -batch -ex "file arch/x86/kvm/kvm.ko" -ex "disassemble kvm_init"
reads the wrong bytes and dumps garbage.
Fixes: dd2776222a ("kbuild: lto: merge module sections")
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210322234438.502582-1-seanjc@google.com
ld-version.sh checks the output from $(LD) --version, but it has a
problem on some locales.
For example, in Italian:
$ LC_MESSAGES=it_IT.UTF-8 ld --version | head -n 1
ld di GNU (GNU Binutils for Debian) 2.35.2
This makes ld-version.sh fail because it expects "GNU ld" for the
BFD linker case.
Add LC_ALL=C to override the user's locale.
BTW, setting LC_MESSAGES=C (or LANG=C) is not enough because it is
ineffective if LC_ALL is set on the user's environment.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=212105
Reported-by: Marco Scardovi
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Recensito-da: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
This is a remnant of commit 78046fabe6 ("kbuild: determine the output
format of DTC by the target suffix").
The parameter "yaml" is meaningless because cmd_dtc no loner takes $(2).
Reported-by: Rob Herring <robh@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This piece of code converts the target suffix to the dtc -O option:
*.dtb -> -O dtb
*.dt.yaml -> -O yaml
Commit ce88c9c794 ("kbuild: Add support to build overlays (%.dtbo)")
added the third case:
*.dtbo -> -O dtbo
This works thanks to commit 163f0469bf2e ("dtc: Allow overlays to have
.dtbo extension") in the upstream DTC, which has already been pulled in
the kernel.
However, I think it is a bit odd because "dtbo" is not a format name.
At least, it does not show up in the help message of dtc.
$ scripts/dtc/dtc --help
[ snip ]
-O, --out-format <arg>
Output formats are:
dts - device tree source text
dtb - device tree blob
yaml - device tree encoded as YAML
asm - assembler source
So, I am not a big fan of the second hunk of that change:
} else if (streq(outform, "dtbo")) {
dt_to_blob(outf, dti, outversion);
Anyway, we did not need to do this in Makefile in the first place.
guess_type_by_name() had already understood ".yaml" before commit
4f0e3a57d6 ("kbuild: Add support for DT binding schema checks"),
and now does ".dtbo" as well.
Makefile does not need to duplicate the same logic. Let's leave it
to dtc.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Commit aec6c60a01 ("kbuild: check the minimum compiler version in
Kconfig") changed how the script detects the compiler version.
Get 'make CROSS_COMPILE=scripts/dummy-tools/' back working again.
Fixes: aec6c60a01 ("kbuild: check the minimum compiler version in Kconfig")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
ppc64le checks for -mprofile-kernel to define MPROFILE_KERNEL Kconfig.
Kconfig calls arch/powerpc/tools/gcc-check-mprofile-kernel.sh for that
purpose. This script performs two checks:
1) build with -mprofile-kernel should contain "_mcount"
2) build with -mprofile-kernel with a function marked as "notrace"
should not produce "_mcount"
So support this in dummy-tools' gcc, so that we have MPROFILE_KERNEL
always true.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Linus reported a build error due to the GCC plugin incompatibility
when the compiler is upgraded. [1]
GCC plugins are tied to a particular GCC version. So, they must be
rebuilt when the compiler is upgraded.
This seems to be a long-standing flaw since the initial support of
GCC plugins.
Extend commit 8b59cd81dc ("kbuild: ensure full rebuild when the
compiler is updated"), so that GCC plugins are covered by the
compiler upgrade detection.
[1]: https://lore.kernel.org/lkml/CAHk-=wieoN5ttOy7SnsGwZv+Fni3R6m-Ut=oxih6bbZ28G+4dw@mail.gmail.com/
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
If LLD was built with -DLLD_VENDOR="xyz", ld.lld --version output
will prefix LLD_VENDOR. Since LLD_VENDOR can contain spaces, the
LLD identifier isn't guaranteed to be $2 either.
Adjust the version checker to handle such versions of lld.
Link: https://lore.kernel.org/lkml/20210302221211.1620858-1-bero@lindev.ch/
Signed-off-by: Bernhard Rosenkränzer <bero@lindev.ch>
[masahiro yamada: refactor the code]
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
There is a test in Kconfig which takes inverted value of a compiler
check:
* config CC_HAS_INT128
def_bool !$(cc-option,$(m64-flag) -D__SIZEOF_INT128__=0)
This results in CC_HAS_INT128 not being in super-config generated by
dummy-tools. So take this into account in the gcc script.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
- Fix coding style issues (Jason Yan)
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Merge tag 'gcc-plugins-v5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull gcc-plugins fixes from Kees Cook:
"Tiny gcc-plugin fixes for v5.12-rc2. These issues are small but have
been reported a couple times now by static analyzers, so best to get
them fixed to reduce the noise. :)
- Fix coding style issues (Jason Yan)"
* tag 'gcc-plugins-v5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
gcc-plugins: latent_entropy: remove unneeded semicolon
gcc-plugins: structleak: remove unneeded variable 'ret'
On little endian system, Use aarch64_be(gcc v7.3) downloaded from
linaro.org to build image with CONFIG_CPU_BIG_ENDIAN = y,
CONFIG_FTRACE = y, CONFIG_DYNAMIC_FTRACE = y.
gcc will create symbols of _mcount but recordmcount can not create
mcount_loc for *.o.
aarch64_be-linux-gnu-objdump -r fs/namei.o | grep mcount
00000000000000d0 R_AARCH64_CALL26 _mcount
...
0000000000007190 R_AARCH64_CALL26 _mcount
The reason is than funciton arm64_is_fake_mcount can not work correctly.
A symbol of _mcount in *.o compiled with big endian compiler likes:
00 00 00 2d 00 00 01 1b
w(rp->r_info) will return 0x2d instead of 0x011b. Because w() takes
uint32_t as parameter, which truncates rp->r_info.
Use w8() instead w() to read relp->r_info
Link: https://lkml.kernel.org/r/20210222135840.56250-1-chenjun102@huawei.com
Fixes: ea0eada456 ("recordmcount: only record relocation of type R_AARCH64_CALL26 on arm64.")
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix the following coccicheck warning:
scripts/gcc-plugins/latent_entropy_plugin.c:539:2-3: Unneeded semicolon
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200418070521.10931-1-yanaijie@huawei.com
Fix the following coccicheck warning:
scripts/gcc-plugins/structleak_plugin.c:177:14-17: Unneeded variable:
"ret". Return "0" on line 207
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200418070505.10715-1-yanaijie@huawei.com
Commit cd195bc477 ("kbuild: split adjust_autoksyms.sh in two parts")
split out the code that needs include/config/auto.conf.
This script no longer needs to include include/config/auto.conf.
Fixes: cd195bc477 ("kbuild: split adjust_autoksyms.sh in two parts")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Commit fbe078d397 ("kbuild: lto: add a default list of used symbols")
does not work as expected if the .config file has already specified
CONFIG_UNUSED_KSYMS_WHITELIST="my/own/white/list" before enabling
CONFIG_LTO_CLANG.
So, the user-supplied whitelist and LTO-specific white list must be
independent of each other.
I refactored the shell script so CONFIG_MODVERSIONS and CONFIG_CLANG_LTO
handle whitelists in the same way.
Fixes: fbe078d397 ("kbuild: lto: add a default list of used symbols")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Some randconfig builds fail with undefined references to _mcount
when CONFIG_TRIM_UNUSED_KSYMS is set:
ERROR: modpost: "_mcount" [drivers/tee/optee/optee.ko] undefined!
ERROR: modpost: "_mcount" [drivers/fsi/fsi-occ.ko] undefined!
ERROR: modpost: "_mcount" [drivers/fpga/dfl-pci.ko] undefined!
Since there is already a list of symbols that get generated at link
time, add this one as well.
Fixes: fbe078d397 ("kbuild: lto: add a default list of used symbols")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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Merge tag 'docs-5.12-2' of git://git.lwn.net/linux
Pull documentation fixes from Jonathan Corbet:
"A handful of late-arriving documentation fixes, nothing all that
notable"
* tag 'docs-5.12-2' of git://git.lwn.net/linux:
docs: proc.rst: fix indentation warning
Documentation: cgroup-v2: fix path to example BPF program
docs: powerpc: Fix tables in syscall64-abi.rst
Documentation: features: refresh feature list
Documentation: features: remove c6x references
docs: ABI: testing: ima_policy: Fixed missing bracket
Fix unaesthetic indentation
scripts: kernel-doc: fix array element capture in pointer-to-func parsing
doc: use KCFLAGS instead of EXTRA_CFLAGS to pass flags from command line
Documentation: proc.rst: add more about the 6 fields in loadavg
Since GCC 8.0 -fsanitize=signed-integer-overflow doesn't work with
-fwrapv. -fwrapv makes signed overflows defines and GCC essentially
disables ubsan checks. On GCC < 8.0 -fwrapv doesn't have influence on
-fsanitize=signed-integer-overflow setting, so it kinda works but
generates false-positves and violates uaccess rules:
lib/iov_iter.o: warning: objtool: iovec_from_user()+0x22d: call to
__ubsan_handle_add_overflow() with UACCESS enabled
Disable signed overflow checks to avoid these problems. Remove unsigned
overflow checks as well. Unsigned overflow appeared as side effect of
commit cdf8a76fda ("ubsan: move cc-option tests into Kconfig"), but it
never worked (kernel doesn't boot). And unsigned overflows are allowed by
C standard, so it just pointless.
Link: https://lkml.kernel.org/r/20210209232348.20510-1-ryabinin.a.a@gmail.com
Signed-off-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the list is uninitialized (next pointer is NULL), list_for_each gets
stuck in an infinite loop. Print a message and treat list as empty.
Link: https://lkml.kernel.org/r/4ae23bb1-c333-f669-da2d-fa35c4f49018@amazon.com
Signed-off-by: George Prekas <prekageo@amazon.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
BPF programs explicitly initialise global variables to 0 to make sure
clang (v10 or older) do not put the variables in the common section. Skip
"initialise globals to 0" check for BPF programs to elimiate error
messages like:
ERROR: do not initialise globals to 0
#19: FILE: samples/bpf/tracex1_kern.c:21:
Link: https://lkml.kernel.org/r/20210209211954.490077-1-songliubraving@fb.com
Signed-off-by: Song Liu <songliubraving@fb.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This check erroneously flags cases like the one in my recent printk
enumeration patch[0], where the spaces are syntactic, and `section:' vs.
`section :' is syntactically important:
ERROR: space prohibited before that ':' (ctx:WxW)
#258: FILE: include/asm-generic/vmlinux.lds.h:314:
+ .printk_fmts : AT(ADDR(.printk_fmts) - LOAD_OFFSET) {
0: https://lore.kernel.org/patchwork/patch/1375749/
Link: https://lkml.kernel.org/r/YBwhqsc2TIVeid3t@chrisdown.name
Link: https://lkml.kernel.org/r/YB6UsjCOy1qrrlSD@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
commit 5799b255c4 ("include/linux/slab.h: add kmalloc_array_node() and
kcalloc_node()") was added in 2017. Update the unnecessary OOM message
test to include it.
Link: https://lkml.kernel.org/r/b9dc4a808b1518e08ab8761480d9872e5d18e7cd.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
objtool requires that all code must be contained in an ELF symbol. Symbol
names that have a '.L' prefix do not emit symbol table entries, as they
have special meaning for the assembler.
'.L' prefixed symbols can be used within a code region, but should be
avoided for denoting a range of code via 'SYM_*_START/END' annotations.
Add a new check to emit a warning on finding the usage of '.L' symbols for
'.S' files, if it denotes range of code via SYM_*_START/END annotation
pair.
Link: https://lkml.kernel.org/r/20210123190459.9701-1-yashsri421@gmail.com
Link: https://lore.kernel.org/lkml/20210112210154.GI4646@sirena.org.uk
Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Suggested-by: Mark Brown <broonie@kernel.org>
Acked-by: Joe Perches <joe@perches.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Aditya Srivastava <yashsri421@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Improve the TYPECAST_INT_CONSTANT test by showing the suggested conversion
for various type of uses like (unsigned int)1 to 1U.
Link: https://lkml.kernel.org/r/ecefe8dcb93fe7028311b69dd297ba52224233d4.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Prefer using ftrace over function entry/exit logging messages.
Warn with various function entry/exit only logging that only
use __func__ with or without descriptive decoration.
Link: https://lkml.kernel.org/r/47c01081533a417c99c9a80a4cd537f8c308503f.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Indentations should use tabs wherever possible.
Replace spaces by tabs for indents.
Link: https://lkml.kernel.org/r/20210105103044.40282-1-dwaipayanray1@gmail.com
Signed-off-by: Dwaipayan Ray <dwaipayanray1@gmail.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some max_length wants to hold as large room as possible to ensure enough
size to tackle with the biggest NR_CPUS. An example below:
kernel/cgroup/cpuset.c:
static struct cftype legacy_files[] = {
{
.name = "cpus",
.seq_show = cpuset_common_seq_show,
.write = cpuset_write_resmask,
.max_write_len = (100U + 6 * NR_CPUS),
.private = FILE_CPULIST,
},
...
}
Link: https://lkml.kernel.org/r/5d4998aa8a8ac7efada2c7daffa9e73559f8b186.1609331255.git.rocking@linux.alibaba.com
Signed-off-by: Peng Wang <rocking@linux.alibaba.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Avoid multiple false positives by ignoring attributes.
Various attributes like volatile and ____cacheline_aligned_in_smp cause
checkpatch to emit invalid "Missing a blank line after declarations"
messages.
Use copies of $sline and $prevline, remove $Attribute and $Sparse, and use
the existing tests to avoid these false positives.
Miscellanea:
o Add volatile to $Attribute
This also reduces checkpatch runtime a bit by moving the indentation
comparison test to the start of the block to avoid multiple unnecessary
regex tests.
Link: https://lkml.kernel.org/r/9015fd00742bf4e5b824ad6d7fd7189530958548.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- 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
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Merge tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
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 misc updates from Andrew Morton:
"A few small subsystems and some of MM.
172 patches.
Subsystems affected by this patch series: hexagon, scripts, ntfs,
ocfs2, vfs, and mm (slab-generic, slab, slub, debug, pagecache, swap,
memcg, pagemap, mprotect, mremap, page-reporting, vmalloc, kasan,
pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
mempolicy, oom-kill, hugetlbfs, and migration)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (172 commits)
mm/migrate: remove unneeded semicolons
hugetlbfs: remove unneeded return value of hugetlb_vmtruncate()
hugetlbfs: fix some comment typos
hugetlbfs: correct some obsolete comments about inode i_mutex
hugetlbfs: make hugepage size conversion more readable
hugetlbfs: remove meaningless variable avoid_reserve
hugetlbfs: correct obsolete function name in hugetlbfs_read_iter()
hugetlbfs: use helper macro default_hstate in init_hugetlbfs_fs
hugetlbfs: remove useless BUG_ON(!inode) in hugetlbfs_setattr()
hugetlbfs: remove special hugetlbfs_set_page_dirty()
mm/hugetlb: change hugetlb_reserve_pages() to type bool
mm, oom: fix a comment in dump_task()
mm/mempolicy: use helper range_in_vma() in queue_pages_test_walk()
numa balancing: migrate on fault among multiple bound nodes
mm, compaction: make fast_isolate_freepages() stay within zone
mm/compaction: fix misbehaviors of fast_find_migrateblock()
mm/compaction: correct deferral logic for proactive compaction
mm/compaction: remove duplicated VM_BUG_ON_PAGE !PageLocked
mm/compaction: remove rcu_read_lock during page compaction
z3fold: simplify the zhdr initialization code in init_z3fold_page()
...
Here are some of the more common spelling mistakes and typos that I've
found while fixing up spelling mistakes in the kernel since September 2020
Link: https://lkml.kernel.org/r/20210210124318.55082-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Here is the large set of char/misc/whatever driver subsystem updates for
5.12-rc1. Over time it seems like this tree is collecting more and more
tiny driver subsystems in one place, making it easier for those
maintainers, which is why this is getting larger.
Included in here are:
- coresight driver updates
- habannalabs driver updates
- virtual acrn driver addition (proper acks from the x86
maintainers)
- broadcom misc driver addition
- speakup driver updates
- soundwire driver updates
- fpga driver updates
- amba driver updates
- mei driver updates
- vfio driver updates
- greybus driver updates
- nvmeem driver updates
- phy driver updates
- mhi driver updates
- interconnect driver udpates
- fsl-mc bus driver updates
- random driver fix
- some small misc driver updates (rtsx, pvpanic, etc.)
All of these have been in linux-next for a while, with the only reported
issue being a merge conflict in include/linux/mod_devicetable.h that you
will hit in your tree due to the dfl_device_id addition from the fpga
subsystem in here. The resolution should be simple.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here is the large set of char/misc/whatever driver subsystem updates
for 5.12-rc1. Over time it seems like this tree is collecting more and
more tiny driver subsystems in one place, making it easier for those
maintainers, which is why this is getting larger.
Included in here are:
- coresight driver updates
- habannalabs driver updates
- virtual acrn driver addition (proper acks from the x86 maintainers)
- broadcom misc driver addition
- speakup driver updates
- soundwire driver updates
- fpga driver updates
- amba driver updates
- mei driver updates
- vfio driver updates
- greybus driver updates
- nvmeem driver updates
- phy driver updates
- mhi driver updates
- interconnect driver udpates
- fsl-mc bus driver updates
- random driver fix
- some small misc driver updates (rtsx, pvpanic, etc.)
All of these have been in linux-next for a while, with the only
reported issue being a merge conflict due to the dfl_device_id
addition from the fpga subsystem in here"
* tag 'char-misc-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (311 commits)
spmi: spmi-pmic-arb: Fix hw_irq overflow
Documentation: coresight: Add PID tracing description
coresight: etm-perf: Support PID tracing for kernel at EL2
coresight: etm-perf: Clarify comment on perf options
ACRN: update MAINTAINERS: mailing list is subscribers-only
regmap: sdw-mbq: use MODULE_LICENSE("GPL")
regmap: sdw: use no_pm routines for SoundWire 1.2 MBQ
regmap: sdw: use _no_pm functions in regmap_read/write
soundwire: intel: fix possible crash when no device is detected
MAINTAINERS: replace my with email with replacements
mhi: Fix double dma free
uapi: map_to_7segment: Update example in documentation
uio: uio_pci_generic: don't fail probe if pdev->irq equals to IRQ_NOTCONNECTED
drivers/misc/vmw_vmci: restrict too big queue size in qp_host_alloc_queue
firewire: replace tricky statement by two simple ones
vme: make remove callback return void
firmware: google: make coreboot driver's remove callback return void
firmware: xilinx: Use explicit values for all enum values
sample/acrn: Introduce a sample of HSM ioctl interface usage
virt: acrn: Introduce an interface for Service VM to control vCPU
...
These have no more user in the upstream code. The use of them has been
warned for a while for external modules. The migration is finished.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Unify the similar build rules.
This supports 'make build_config', which builds scripts/kconfig/conf
but does not invoke it.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
scripts/kconfig/conf.c line 39 defines the default of input_mode as
oldaskconfig. Hence, 'make config' works in the same way even without
the --oldaskconfig option given. Note this in the help message.
This will be helpful to unify build rules in Makefile in the next
commit.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
scripts/kconfig/conf supports -? option to show the help message.
This is not wired up to Makefile, so nobody would notice this, but
it also shows 'invalid option' message.
$ ./scripts/kconfig/conf -?
./scripts/kconfig/conf: invalid option -- '?'
Usage: ./scripts/kconfig/conf [-s] [option] <kconfig-file>
[option] is _one_ of the following:
--listnewconfig List new options
--helpnewconfig List new options and help text
--oldaskconfig Start a new configuration using a line-oriented program
...
The reason is the '?' is missing in the short option list passed to
getopt_long().
While I fixed this issue, I also changed the option '?' to 'h'.
I prefer -h (or --help, if a long option is also desired).
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
conf_askvalue() is only called for oldconfig, syncconfig, and
oldaskconfig. If it is called for other cases, it is a bug.
So, the code after the switch statement is unreachable.
Remove the dead code, and clean up the switch statement.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Unify the outer two if-conditionals into one. This decreases the
indent level by one.
Also, change the if-else blocks:
if (input_mode == listnewconfig) {
...
} else if (input_mode == helpnewconfig) {
...
} else {
...
}
into the switch statement.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Use the saved returned value of sym_get_string_value() instead of
calling it twice.
Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
Link: https://lore.kernel.org/r/20210215181511.2840674-2-mic@digikod.net
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
With c6x architecture removal, scripts/dtc/include-prefixes/c6x symlink
lost its target. Drop the dangling symlink which triggers some distribution
check scripts.
Fixes: a579fcfa8e ("c6x: remove architecture")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210223204114.E7F55E0155@unicorn.suse.cz
- Generate __mcount_loc in objtool (Peter Zijlstra)
- Support running objtool against vmlinux.o (Sami Tolvanen)
- Clang LTO enablement for x86 (Sami Tolvanen)
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Merge tag 'clang-lto-v5.12-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
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
Commit 0da6bcd9fc ("scripts: dtc: Build fdtoverlay tool") enabled
building fdtoverlay, but failed to add it to .gitignore.
Also add a note to keep hostprogs in sync with .gitignore.
Fixes: 0da6bcd9fc ("scripts: dtc: Build fdtoverlay tool")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
With LTO, LLVM bitcode won't be compiled into native code until
modpost_link, or modfinal for modules. This change postpones calls
to objtool until after these steps, and moves objtool_args to
Makefile.lib, so the arguments can be reused in Makefile.modfinal.
As we didn't have objects to process earlier, we use --duplicate
when processing vmlinux.o. This change also disables unreachable
instruction warnings with LTO to avoid warnings about the int3
padding between functions.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
This change adds a --noinstr flag to objtool to allow us to specify
that we're processing vmlinux.o without also enabling noinstr
validation. This is needed to avoid false positives with LTO when we
run objtool on vmlinux.o without CONFIG_DEBUG_ENTRY.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
