- Jan 20, 2022
-
-
Kees Cook authored
The object-size sanitizer is redundant to -Warray-bounds, and inappropriately performs its checks at run-time when all information needed for the evaluation is available at compile-time, making it quite difficult to use: https://bugzilla.kernel.org/show_bug.cgi?id=214861 With -Warray-bounds almost enabled globally, it doesn't make sense to keep this around. Link: https://lkml.kernel.org/r/20211203235346.110809-1-keescook@chromium.org Signed-off-by:
Kees Cook <keescook@chromium.org> Reviewed-by:
Marco Elver <elver@google.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Michal Marek <michal.lkml@markovi.net> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
Rikard Falkeborn authored
Add commonly used structs (>50 instances) which are always or almost always const. Link: https://lkml.kernel.org/r/20211127101134.33101-1-rikard.falkeborn@gmail.com Signed-off-by:
Rikard Falkeborn <rikard.falkeborn@gmail.com> Cc: Joe Perches <joe@perches.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
Joe Perches authored
The Kconfig help test erroneously counts patch context lines as part of the help text. Fix that and improve the message block output. Link: https://lkml.kernel.org/r/06c0cdc157ae1502e8e9eb3624b9ea995cf11e7a.camel@perches.com Signed-off-by:
Joe Perches <joe@perches.com> Tested-by:
Randy Dunlap <rdunlap@infradead.org> Acked-by:
Randy Dunlap <rdunlap@infradead.org> Cc: Andy Whitcroft <apw@canonical.com> Cc: Dwaipayan Ray <dwaipayanray1@gmail.com> Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
Jerome Forissier authored
One exceptions to the COMMIT_LOG_LONG_LINE rule is a file path followed by ':'. That is typically some sort diagnostic message from a compiler or a build tool, in which case we don't want to wrap the lines but keep the message unmodified. The regular expression used to match this pattern currently doesn't accept absolute paths or + characters. This can result in false positives as in the following (out-of-tree) example: ... /home/jerome/work/optee_repo_qemu/build/../toolchains/aarch32/bin/arm-linux-gnueabihf-ld.bfd: /home/jerome/work/toolchains-gcc10.2/aarch32/bin/../lib/gcc/arm-none-linux-gnueabihf/10.2.1/../../../../arm-none-linux-gnueabihf/lib/libstdc++.a(eh_alloc.o): in function `__cxa_allocate_exception': /tmp/dgboter/bbs/build03--cen7x86_64/buildbot/cen7x86_64--arm-none-linux-gnueabihf/build/src/gcc/libstdc++-v3/libsupc++/eh_alloc.cc:284: undefined reference to `malloc' ... Update the regular expression to match the above paths. Link: https://lkml.kernel.org/r/20210923143842.2837983-1-jerome@forissier.org Signed-off-by:
Jerome Forissier <jerome@forissier.org> Acked-by:
Joe Perches <joe@perches.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: Dwaipayan Ray <dwaipayanray1@gmail.com> Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
Randy Dunlap authored
When --nogit is used with scripts/get_maintainer.pl, the script spews 4 lines of unnecessary information (noise). Do not print those lines when --nogit is specified. This change removes the printing of these 4 lines: ./scripts/get_maintainer.pl: No supported VCS found. Add --nogit to options? Using a git repository produces better results. Try Linus Torvalds' latest git repository using: git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git Link: https://lkml.kernel.org/r/20220102031424.3328-1-rdunlap@infradead.org Signed-off-by:
Randy Dunlap <rdunlap@infradead.org> Cc: Joe Perches <joe@perches.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
- Jan 18, 2022
-
-
Yinan Liu authored
elf_mcount_loc and mcount_sort_thread definitions are not initialized immediately within the function, which can cause the judgment logic to use uninitialized values when the initialization logic of subsequent code fails. Link: https://lkml.kernel.org/r/20211212113358.34208-2-yinan@linux.alibaba.com Link: https://lkml.kernel.org/r/20220118065241.42364-1-yinan@linux.alibaba.com Fixes: 72b3942a ("scripts: ftrace - move the sort-processing in ftrace_init") Tested-by:
Nathan Chancellor <nathan@kernel.org> Reviewed-by:
Nathan Chancellor <nathan@kernel.org> Signed-off-by:
Yinan Liu <yinan@linux.alibaba.com> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
-
- Jan 15, 2022
-
-
Drew Fustini authored
Add typo "oveflow" for "overflow". This typo was found and fixed in tools/testing/selftests/bpf/prog_tests/btf_dump.c Link: https://lore.kernel.org/all/20211122070528.837806-1-dfustini@baylibre.com/ Link: https://lkml.kernel.org/r/20211122072302.839102-1-dfustini@baylibre.com Signed-off-by:
Drew Fustini <dfustini@baylibre.com> Suggested-by:
Gustavo A. R. Silva <gustavoars@kernel.org> Cc: Colin Ian King <colin.king@intel.com> Cc: Drew Fustini <dfustini@baylibre.com> Cc: zuoqilin <zuoqilin@yulong.com> Cc: Tom Saeger <tom.saeger@oracle.com> Cc: Sven Eckelmann <sven@narfation.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
Julia Lawall authored
This semantic patch does not take into account the fact that of_node_put can be safely applied to NULL. Thus it gives only false positives. Drop it. Reported-by:
Qing Wang <wangqing@vivo.com> Signed-off-by:
Julia Lawall <Julia.Lawall@inria.fr>
-
Julia Lawall authored
The BUG_ON script was never safe, in that it was not able to check whether the condition was side-effecting. At this point, BUG_ON should be well known, so it has probably outlived its usefuless. Signed-off-by:
Julia Lawall <Julia.Lawall@inria.fr> Suggested-by:
Matthew Wilcox <willy@infradead.org>
-
- Jan 13, 2022
-
-
Yinan Liu authored
When the kernel starts, the initialization of ftrace takes up a portion of the time (approximately 6~8ms) to sort mcount addresses. We can save this time by moving mcount-sorting to compile time. Link: https://lkml.kernel.org/r/20211212113358.34208-2-yinan@linux.alibaba.com Signed-off-by:
Yinan Liu <yinan@linux.alibaba.com> Reported-by:
kernel test robot <lkp@intel.com> Reported-by:
kernel test robot <oliver.sang@intel.com> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
-
Masahiro Yamada authored
Some architectures support self-extracting kernel, which embeds the compressed vmlinux. It has 4 byte data at the end so the decompressor can know the vmlinux size beforehand. GZIP natively has it in the trailer, but for the other compression algorithms, the hand-crafted trailer is added. It is unneeded to generate such _corrupted_ compressed files because it is possible to pass the size data as a separate file. For example, the assembly code: .incbin "compressed-vmlinux-with-size-data" can be transformed to: .incbin "compressed-vmlinux" .incbin "size-data" My hope is, after some reworks of the decompressors, the macros cmd_{bzip2,lzma,lzo,lz4,xzkern,zstd22}_with_size will go away. This new macro, cmd_file_size, will be useful to generate a separate size-data file. Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org> Reviewed-by:
Nicolas Schier <n.schier@avm.de>
-
Masahiro Yamada authored
GZIP-compressed files end with 4 byte data that represents the size of the original input. The decompressors (the self-extracting kernel) exploit it to know the vmlinux size beforehand. To mimic the GZIP's trailer, Kbuild provides cmd_{bzip2,lzma,lzo,lz4,xzkern,zstd22}. Unfortunately these macros are used everywhere despite the appended size data is only useful for the decompressors. There is no guarantee that such hand-crafted trailers are safely ignored. In fact, the kernel refuses compressed initramdfs with the garbage data. That is why usr/Makefile overrides size_append to make it no-op. To limit the use of such broken compressed files, this commit renames the existing macros as follows: cmd_bzip2 --> cmd_bzip2_with_size cmd_lzma --> cmd_lzma_with_size cmd_lzo --> cmd_lzo_with_size cmd_lz4 --> cmd_lz4_with_size cmd_xzkern --> cmd_xzkern_with_size cmd_zstd22 --> cmd_zstd22_with_size To keep the decompressors working, I...
-
Masahiro Yamada authored
The appended file size is only used by the decompressors, which some architectures support. As the comment "zstd22 is used for kernel compression" says, cmd_zstd22 is used in arch/{mips,s390,x86}/boot/compressed/Makefile. On the other hand, there is no good reason to append the file size to cmd_zstd since it is used for other purposes. Actually cmd_zstd is only used in usr/Makefile, where the appended file size is rather harmful. The initramfs with its file size appended is considered as corrupted data, so commit 65e00e04 ("initramfs: refactor the initramfs build rules") added 'override size_append := :' to make it no-op. As a conclusion, this $(size_append) should not exist here. Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org> Reviewed-by:
Nicolas Schier <n.schier@avm.de>
-
- Jan 08, 2022
-
-
Masahiro Yamada authored
extract-cert is only used in certs/Makefile. Move it there and build extract-cert on demand. Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org>
-
Masahiro Yamada authored
The previous commit fixed up all shell scripts to not include include/config/auto.conf. Now that include/config/auto.conf is only included by Makefiles, we can change it into a more Make-friendly form. Previously, Kconfig output string values enclosed with double-quotes (both in the .config and include/config/auto.conf): CONFIG_X="foo bar" Unlike shell, Make handles double-quotes (and single-quotes as well) verbatim. We must rip them off when used. There are some patterns: [1] $(patsubst "%",%,$(CONFIG_X)) [2] $(CONFIG_X:"%"=%) [3] $(subst ",,$(CONFIG_X)) [4] $(shell echo $(CONFIG_X)) These are not only ugly, but also fragile. [1] and [2] do not work if the value contains spaces, like CONFIG_X=" foo bar " [3] does not work correctly if the value contains double-quotes like CONFIG_X="foo\"bar" [4] seems to work better, but has a cost of forking a process. Anyway, quoted strings were always PITA for our Makefiles. This commit changes Kconfig to stop quoting in include/config/auto.conf. These are the string type symbols referenced in Makefiles or scripts: ACPI_CUSTOM_DSDT_FILE ARC_BUILTIN_DTB_NAME ARC_TUNE_MCPU BUILTIN_DTB_SOURCE CC_IMPLICIT_FALLTHROUGH CC_VERSION_TEXT CFG80211_EXTRA_REGDB_KEYDIR EXTRA_FIRMWARE EXTRA_FIRMWARE_DIR EXTRA_TARGETS H8300_BUILTIN_DTB INITRAMFS_SOURCE LOCALVERSION MODULE_SIG_HASH MODULE_SIG_KEY NDS32_BUILTIN_DTB NIOS2_DTB_SOURCE OPENRISC_BUILTIN_DTB SOC_CANAAN_K210_DTB_SOURCE SYSTEM_BLACKLIST_HASH_LIST SYSTEM_REVOCATION_KEYS SYSTEM_TRUSTED_KEYS TARGET_CPU UNUSED_KSYMS_WHITELIST XILINX_MICROBLAZE0_FAMILY XILINX_MICROBLAZE0_HW_VER XTENSA_VARIANT_NAME I checked them one by one, and fixed up the code where necessary. Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org>
-
Masahiro Yamada authored
Richard Weinberger pointed out the risk of sourcing the kernel config from shell scripts [1], and proposed some patches [2], [3]. It is a good point, but it took a long time because I was wondering how to fix this. This commit goes with simple grep approach because there are only a few scripts including the kernel configuration. scripts/link_vmlinux.sh has references to a bunch of CONFIG options, all of which are boolean. I added is_enabled() helper as scripts/package/{mkdebian,builddeb} do. scripts/gen_autoksyms.sh uses 'eval', stating "to expand the whitelist path". I removed it since it is the issue we are trying to fix. I was a bit worried about the cost of invoking the grep command over again. I extracted the grep parts from it, and measured the cost. It was approximately 0.03 sec, which I hope is acceptable. [test code] $ cat test-grep.sh #!/bin/sh is_enabled() { grep -q "^$1=y" include/config/auto.conf } is_enabled CONFIG_LTO_CLANG is_enabled CONFIG_LTO_CLANG is_enabled CONFIG_STACK_VALIDATION is_enabled CONFIG_UNWINDER_ORC is_enabled CONFIG_FTRACE_MCOUNT_USE_OBJTOOL is_enabled CONFIG_VMLINUX_VALIDATION is_enabled CONFIG_FRAME_POINTER is_enabled CONFIG_GCOV_KERNEL is_enabled CONFIG_LTO_CLANG is_enabled CONFIG_RETPOLINE is_enabled CONFIG_X86_SMAP is_enabled CONFIG_LTO_CLANG is_enabled CONFIG_VMLINUX_MAP is_enabled CONFIG_KALLSYMS_ALL is_enabled CONFIG_KALLSYMS_ABSOLUTE_PERCPU is_enabled CONFIG_KALLSYMS_BASE_RELATIVE is_enabled CONFIG_DEBUG_INFO_BTF is_enabled CONFIG_KALLSYMS is_enabled CONFIG_DEBUG_INFO_BTF is_enabled CONFIG_BPF is_enabled CONFIG_BUILDTIME_TABLE_SORT is_enabled CONFIG_KALLSYMS $ time ./test-grep.sh real 0m0.036s user 0m0.027s sys m0.009s [1]: https://lore.kernel.org/all/1919455.eZKeABUfgV@blindfold/ [2]: https://lore.kernel.org/all/20180219092245.26404-1-richard@nod.at/ [3]: https://lore.kernel.org/all/20210920213957.1064-2-richard@nod.at/ Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org> Reviewed-by:
Nicolas Schier <n.schier@avm.de>
-
Masahiro Yamada authored
The complex macro, config_filename, was introduced to do: [1] drop double-quotes from the string value [2] add $(srctree)/ prefix in case the file is not found in $(objtree) [3] escape spaces and more [1] will be more generally handled by Kconfig later. As for [2], Kbuild uses VPATH to search for files in $(objtree), $(srctree) in this order. GNU Make can natively handle it. As for [3], converting $(space) to $(space_escape) back and forth looks questionable to me. It is well-known that GNU Make cannot handle file paths with spaces in the first place. Instead of using the complex macro, use $< so it will be expanded to the file path of the key. Remove config_filename, finally. Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org>
-
Masahiro Yamada authored
Toward the goal of removing the config_filename macro, drop the double-quotes and add $(srctree)/ prefix in an ad hoc way. Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org> Reviewed-by:
Nicolas Schier <n.schier@avm.de>
-
Masahiro Yamada authored
This script is only used by usr/include/Makefile. Make it local to the directory. Update the comment in include/uapi/linux/soundcard.h because 'make headers_check' is no longer functional. Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org>
-
- Jan 07, 2022
-
-
Mauro Carvalho Chehab authored
The name of the package with ctexhook.sty is different on Debian/Ubuntu. Reported-by:
Akira Yokosawa <akiyks@gmail.com> Signed-off-by:
Mauro Carvalho Chehab <mchehab@kernel.org> Tested-by:
Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/r/63882425609a2820fac78f5e94620abeb7ed5f6f.1641429634.git.mchehab@kernel.org Signed-off-by:
Jonathan Corbet <corbet@lwn.net>
-
- Jan 05, 2022
-
-
Jisheng Zhang authored
This is a riscv port of commit d6e2cc56 ("arm64: extable: add `type` and `data` fields"). Signed-off-by:
Jisheng Zhang <jszhang@kernel.org> Signed-off-by:
Palmer Dabbelt <palmer@rivosinc.com>
-
Jisheng Zhang authored
Similar as other architectures such as arm64, x86 and so on, use offsets relative to the exception table entry values rather than absolute addresses for both the exception locationand the fixup. However, RISCV label difference will actually produce two relocations, a pair of R_RISCV_ADD32 and R_RISCV_SUB32. Take below simple code for example: $ cat test.S .section .text 1: nop .section __ex_table,"a" .balign 4 .long (1b - .) .previous $ riscv64-linux-gnu-gcc -c test.S $ riscv64-linux-gnu-readelf -r test.o Relocation section '.rela__ex_table' at offset 0x100 contains 2 entries: Offset Info Type Sym. Value Sym. Name + Addend 000000000000 000600000023 R_RISCV_ADD32 0000000000000000 .L1^B1 + 0 000000000000 000500000027 R_RISCV_SUB32 0000000000000000 .L0 + 0 The modpost will complain the R_RISCV_SUB32 relocation, so we need to patch modpost.c to skip this relocation for .rela__ex_table section. After this patch, the __ex_table section size of defconfig vmlinux is reduced from 7072 Bytes to 3536 Bytes. Signed-off-by:
Jisheng Zhang <jszhang@kernel.org> Reviewed-by:
Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by:
Palmer Dabbelt <palmer@rivosinc.com>
-
Mark Rutland authored
The format of the arm64 and x86 exception table entries is essentially the same as of commits: 46d28947 ("x86/extable: Rework the exception table mechanics") d6e2cc56 ("arm64: extable: add `type` and `data` fields") Both use a 12-byte entry consisting of two 32-bit relative offsets and 32 bits of (absolute) data, and their sort functions are identical aside from commentary, with arm64 saying: /* Don't touch the fixup type or data */ ... and x86 saying: /* Don't touch the fixup type */ Unify the two behind a common sort_relative_table_with_data() function, retaining the arm64 commentary. There should be no functional change as a result of this patch. Signed-off-by:
Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by:
Palmer Dabbelt <palmer@rivosinc.com>
-
- Jan 04, 2022
-
-
Masahiro Yamada authored
As commit 7ae4a78d ("ARM: 8969/1: decompressor: simplify libfdt builds") stated, copying source files during the build time may not end up with as clean code as expected. Do similar for parisc to clean up the Makefile. Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org> Acked-by:
Helge Deller <deller@gmx.de> Signed-off-by:
Helge Deller <deller@gmx.de>
-
- Jan 03, 2022
-
-
Mauro Carvalho Chehab authored
After a change meant to fix support for oriental characters (Chinese, Japanese, Korean), ctex stylesheet is now a requirement for PDF output. Reported-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Mauro Carvalho Chehab <mchehab@kernel.org> Link: https://lore.kernel.org/r/165aa6167f21e3892a6e308688c93c756e94f4e0.1641243581.git.mchehab@kernel.org Signed-off-by:
Jonathan Corbet <corbet@lwn.net>
-
- Dec 24, 2021
-
-
Heiko Carstens authored
Commit 85bf17b2 ("recordmcount.pl: look for jgnop instruction as well as bcrl on s390") added a new alternative mnemonic for the existing brcl instruction. This is required for the combination old gcc version (pre 9.0) and binutils since version 2.37. However at the same time this commit introduced a typo, replacing brcl with bcrl. As a result no mcount locations are detected anymore with old gcc versions (pre 9.0) and binutils before version 2.37. Fix this by using the correct mnemonic again. Reported-by:
Miroslav Benes <mbenes@suse.cz> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: <stable@vger.kernel.org> Fixes: 85bf17b2 ("recordmcount.pl: look for jgnop instruction as well as bcrl on s390") Link: https://lore.kernel.org/r/alpine.LSU.2.21.2112230949520.19849@pobox.suse.cz Signed-off-by:
Heiko Carstens <hca@linux.ibm.com>
-
- Dec 17, 2021
-
-
Masahiro Yamada authored
As commit 7ae4a78d ("ARM: 8969/1: decompressor: simplify libfdt builds") stated, copying source files during the build time may not end up with as clean code as expected. Do similar for the other library files for further cleanups of the Makefile and .gitignore. Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org> Signed-off-by:
Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
-
- Dec 16, 2021
-
-
John Ogness authored
For the gdb command lx-dmesg, the entire descriptor, info, and text data regions are read into memory before printing any records. For large kernel log buffers, this not only causes a huge delay before seeing any records, but it may also lead to python errors of too much memory allocation. Rather than reading in all these regions in advance, read them as needed and only read the regions for the particular record that is being printed. The gdb macro "dmesg" in Documentation/admin-guide/kdump/gdbmacros.txt already prints out the kernel log buffer like this. Signed-off-by:
John Ogness <john.ogness@linutronix.de> Signed-off-by:
Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/874k79c3a9.fsf@jogness.linutronix.de
-
- Dec 12, 2021
-
-
Jerome Marchand authored
On s390, recordmcount.pl is looking for "bcrl 0,<xxx>" instructions in the objdump -d outpout. However since binutils 2.37, objdump -d display "jgnop <xxx>" for the same instruction. Update the mcount_regex so that it accepts both. Signed-off-by:
Jerome Marchand <jmarchan@redhat.com> Reviewed-by:
Miroslav Benes <mbenes@suse.cz> Acked-by:
Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20211210093827.1623286-1-jmarchan@redhat.com Signed-off-by:
Heiko Carstens <hca@linux.ibm.com>
-
- Dec 11, 2021
-
-
Yinan Liu authored
Modified the code style issue of if() {}, keep the code style consistent. Link: https://lkml.kernel.org/r/20211207151348.54921-3-yinan@linux.alibaba.com Signed-off-by:
Yinan Liu <yinan@linux.alibaba.com> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
-
- Dec 09, 2021
-
-
Marco Elver authored
Adds the required KCSAN instrumentation for barriers of atomics. Signed-off-by:
Marco Elver <elver@google.com> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
-
Marco Elver authored
GCC 11 has introduced a new warning option, -Wtsan [1], to warn about unsupported operations in the TSan runtime. But KCSAN != TSan runtime, so none of the warnings apply. [1] https://gcc.gnu.org/onlinedocs/gcc-11.1.0/gcc/Warning-Options.html Ignore the warnings. Currently the warning only fires in the test for __atomic_thread_fence(): kernel/kcsan/kcsan_test.c: In function ‘test_atomic_builtins’: kernel/kcsan/kcsan_test.c:1234:17: warning: ‘atomic_thread_fence’ is not supported with ‘-fsanitize=thread’ [-Wtsan] 1234 | __atomic_thread_fence(__ATOMIC_SEQ_CST); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ which exists to ensure the KCSAN runtime keeps supporting the builtin instrumentation. Signed-off-by:
Marco Elver <elver@google.com> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
-
Marco Elver authored
Source files that disable KCSAN via KCSAN_SANITIZE := n, remove all instrumentation, including explicit barrier instrumentation. With instrumentation for memory barriers, in few places it is required to enable just the explicit instrumentation for memory barriers to avoid false positives. Providing the Makefile variable KCSAN_INSTRUMENT_BARRIERS_obj.o or KCSAN_INSTRUMENT_BARRIERS (for all files) set to 'y' only enables the explicit barrier instrumentation. Signed-off-by:
Marco Elver <elver@google.com> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
-
Marco Elver authored
Add support for modeling a subset of weak memory, which will enable detection of a subset of data races due to missing memory barriers. KCSAN's approach to detecting missing memory barriers is based on modeling access reordering, and enabled if `CONFIG_KCSAN_WEAK_MEMORY=y`, which depends on `CONFIG_KCSAN_STRICT=y`. The feature can be enabled or disabled at boot and runtime via the `kcsan.weak_memory` boot parameter. Each memory access for which a watchpoint is set up, is also selected for simulated reordering within the scope of its function (at most 1 in-flight access). We are limited to modeling the effects of "buffering" (delaying the access), since the runtime cannot "prefetch" accesses (therefore no acquire modeling). Once an access has been selected for reordering, it is checked along every other access until the end of the function scope. If an appropriate memory barrier is encountered, the access will no longer be considered for reordering. When the result of a memory operation should be ordered by a barrier, KCSAN can then detect data races where the conflict only occurs as a result of a missing barrier due to reordering accesses. Suggested-by:
Dmitry Vyukov <dvyukov@google.com> Signed-off-by:
Marco Elver <elver@google.com> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
-
Peter Zijlstra authored
Make use of an upcoming GCC feature to mitigate straight-line-speculation for x86: https://gcc.gnu.org/g:53a643f8568067d7700a9f2facc8ba39974973d3 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102952 https://bugs.llvm.org/show_bug.cgi?id=52323 It's built tested on x86_64-allyesconfig using GCC-12 and GCC-11. Maintenance overhead of this should be fairly low due to objtool validation. Size overhead of all these additional int3 instructions comes to: text data bss dec hex filename 22267751 6933356 2011368 31212475 1dc43bb defconfig-build/vmlinux 22804126 6933356 1470696 31208178 1dc32f2 defconfig-build/vmlinux.sls Or roughly 2.4% additional text. Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by:
Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20211204134908.140103474@infradead.org
-
- Dec 02, 2021
-
-
Nathan Chancellor authored
LLVM versions prior to 11.0.0 have a harder time with dead code elimination, which can cause issues with commonly used expressions such as BUILD_BUG_ON and the bitmask functions/macros in bitfield.h (see the first two issues links below). Whenever there is an issue within LLVM that has been resolved in a later release, the only course of action is to gate the problematic configuration or source code on the toolchain verson or raise the minimum supported version of LLVM for building the kernel, as LLVM has a limited support lifetime compared to GCC. GCC major releases will typically see a few point releases across a two year period on average whereas LLVM major releases are only supported until the next major release and will only see one or two point releases within that timeframe. For example, GCC 8.1 was released in May 2018 and GCC 8.5 was released in May 2021, whereas LLVM 12.0.0 was released in April 2021 and its only point release, 12.0.1, was released in July 2021, giving a minimal window for fixes to be backported. To resolve these build errors around improper dead code elimination, raise the minimum supported version of LLVM for building the kernel to 11.0.0. Doing so is a more proper solution than mucking around with core kernel macros that have always worked with GCC or disabling drivers for using these macros in a proper manner. This type of issue may continue to crop up and require patching, which creates more debt for bumping the minimum supported version in the future. This should have a minimal impact to distributions. Using a script to pull several different Docker images and check the output of 'clang --version': archlinux:latest: clang version 13.0.0 debian:oldoldstable-slim: clang version 3.8.1-24 (tags/RELEASE_381/final) debian:oldstable-slim: clang version 7.0.1-8+deb10u2 (tags/RELEASE_701/final) debian:stable-slim: Debian clang version 11.0.1-2 debian:testing-slim: Debian clang version 11.1.0-4 debian:unstable-slim: Debian clang version 11.1.0-4 fedora:34: clang version 12.0.1 (Fedora 12.0.1-1.fc34) fedora:latest: clang version 13.0.0 (Fedora 13.0.0-3.fc35) fedora:rawhide: clang version 13.0.0 (Fedora 13.0.0-5.fc36) opensuse/leap:15.2: clang version 9.0.1 opensuse/leap:latest: clang version 11.0.1 opensuse/tumbleweed:latest: clang version 13.0.0 ubuntu:bionic: clang version 6.0.0-1ubuntu2 (tags/RELEASE_600/final) ubuntu:latest: clang version 10.0.0-4ubuntu1 ubuntu:hirsute: Ubuntu clang version 12.0.0-3ubuntu1~21.04.2 ubuntu:rolling: Ubuntu clang version 13.0.0-2 ubuntu:devel: Ubuntu clang version 13.0.0-9 In every case, the distribution's version of clang is either older than the current minimum supported version of LLVM 10.0.1 or equal to or greater than the proposed 11.0.0 so nothing should change. Another benefit of this change is LLVM=1 works better with arm64 and x86_64 since commit f12b034a ("scripts/Makefile.clang: default to LLVM_IAS=1") enabled the integrated assembler by default, which only works well with clang 11+ (clang-10 required it to be disabled to successfully build a kernel). Link: https://github.com/ClangBuiltLinux/linux/issues/1293 Link: https://github.com/ClangBuiltLinux/linux/issues/1506 Link: https://github.com/ClangBuiltLinux/linux/issues/1511 Link: https://github.com/llvm/llvm-project/commit/fa496ce3c6774097080c8a9cb808da56f383b938 Link: https://groups.google.com/g/clang-built-linux/c/mPQb9_ZWW0s/m/W7o6S-QTBAAJ Link: https://github.com/ClangBuiltLinux/misc-scripts Signed-off-by:
Nathan Chancellor <nathan@kernel.org> Reviewed-by:
Miguel Ojeda <ojeda@kernel.org> Reviewed-by:
Mark Brown <broonie@kernel.org> Reviewed-by:
Nick Desaulniers <ndesaulniers@google.com> Reviewed-by:
Kees Cook <keescook@chromium.org> Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org>
-
Łukasz Stelmach authored
Show the very same file name that was passed to open() in case the operation failed. Signed-off-by:
Łukasz Stelmach <l.stelmach@samsung.com>
-
Josh Triplett authored
When converting a modular kernel to a monolithic kernel, once the kernel works without loading any modules, this helps to quickly disable all the modules before turning off module support entirely. Refactor conf_rewrite_mod_or_yes to a more general conf_rewrite_tristates that accepts an old and new state. Signed-off-by:
Josh Triplett <josh@joshtriplett.org> Tested-by:
Björn Töpel <bjorn@kernel.org> Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org>
-
- Nov 26, 2021
-
-
Zhaoyu Liu authored
When "make tags", it prompts a warning: ctags: Warning: drivers/pci/controller/pcie-apple.c:150: null expansion of name pattern "\1" The reason is that there is an indentation beside arguments of DECLARE_BITMAP, but it can parsed normally by gtags. It's also allowed in C. Regex [:space:] can match any white space character, so it's a better approach to add it to each item in regex_c. Suggested-by:
Marc Zyngier <maz@kernel.org> Signed-off-by:
Zhaoyu Liu <zackary.liu.pro@gmail.com> Link: https://lore.kernel.org/r/20211103152234.GA23295@pc Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
- Nov 10, 2021
-
-
Masahiro Yamada authored
As commit 7ae4a78d ("ARM: 8969/1: decompressor: simplify libfdt builds") stated, copying source files during the build time may not end up with as clean code as expected. Do similar for mips to clean up the Makefile and .gitignore. Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org> Tested-by:
Paul Cercueil <paul@crapouillou.net> Signed-off-by:
Thomas Bogendoerfer <tsbogend@alpha.franken.de>
-