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2021-07-18Linux 5.14-rc2v5.14-rc2Linus Torvalds
2021-07-18Merge tag 'kbuild-fixes-v5.14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild fixes from Masahiro Yamada: - Restore the original behavior of scripts/setlocalversion when LOCALVERSION is set to empty. - Show Kconfig prompts even for 'make -s' - Fix the combination of COFNIG_LTO_CLANG=y and CONFIG_MODVERSIONS=y for older GNU Make versions * tag 'kbuild-fixes-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: Documentation: Fix intiramfs script name Kbuild: lto: fix module versionings mismatch in GNU make 3.X kbuild: do not suppress Kconfig prompts for silent build scripts/setlocalversion: fix a bug when LOCALVERSION is empty
2021-07-18kbuild: do not suppress Kconfig prompts for silent buildMasahiro Yamada
When a new CONFIG option is available, Kbuild shows a prompt to get the user input. $ make [ snip ] Core Scheduling for SMT (SCHED_CORE) [N/y/?] (NEW) This is the only interactive place in the build process. Commit 174a1dcc9642 ("kbuild: sink stdout from cmd for silent build") suppressed Kconfig prompts as well because syncconfig is invoked by the 'cmd' macro. You cannot notice the fact that Kconfig is waiting for the user input. Use 'kecho' to show the equivalent short log without suppressing stdout from sub-make. Fixes: 174a1dcc9642 ("kbuild: sink stdout from cmd for silent build") Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2021-07-15Revert "Makefile: Enable -Wimplicit-fallthrough for Clang"Linus Torvalds
This reverts commit b7eb335e26a9c7f258c96b3962c283c379d3ede0. It turns out that the problem with the clang -Wimplicit-fallthrough warning is not about the kernel source code, but about clang itself, and that the warning is unusable until clang fixes its broken ways. In particular, when you enable this warning for clang, you not only get warnings about implicit fallthroughs. You also get this: warning: fallthrough annotation in unreachable code [-Wimplicit-fallthrough] which is completely broken becasue it (a) doesn't even tell you where the problem is (seriously: no line numbers, no filename, no nothing). (b) is fundamentally broken anyway, because there are perfectly valid reasons to have a fallthrough statement even if it turns out that it can perhaps not be reached. In the kernel, an example of that second case is code in the scheduler: switch (state) { case cpuset: if (IS_ENABLED(CONFIG_CPUSETS)) { cpuset_cpus_allowed_fallback(p); state = possible; break; } fallthrough; case possible: where if CONFIG_CPUSETS is enabled you actually never hit the fallthrough case at all. But that in no way makes the fallthrough wrong. So the warning is completely broken, and enabling it for clang is a very bad idea. In the meantime, we can keep the gcc option enabled, and make the gcc build use -Wimplicit-fallthrough=5 which means that we will at least continue to require a proper fallthrough statement, and that gcc won't silently accept the magic comment versions. Because gcc does this all correctly, and while the odd "=5" part is kind of obscure, it's documented in [1]: "-Wimplicit-fallthrough=5 doesn’t recognize any comments as fallthrough comments, only attributes disable the warning" so if clang ever fixes its bad behavior we can try enabling it there again. Link: https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html [1] Cc: Kees Cook <keescook@chromium.org> Cc: Gustavo A. R. Silva <gustavoars@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-14Makefile: Enable -Wimplicit-fallthrough for ClangGustavo A. R. Silva
With the recent fixes for fallthrough warnings, it is now possible to enable -Wimplicit-fallthrough for Clang. It's important to mention that since we have adopted the use of the pseudo-keyword macro fallthrough; we also want to avoid having more /* fall through */ comments being introduced. Notice that contrary to GCC, Clang doesn't recognize any comments as implicit fall-through markings when the -Wimplicit-fallthrough option is enabled. So, in order to avoid having more comments being introduced, we have to use the option -Wimplicit-fallthrough=5 for GCC, which similar to Clang, will cause a warning in case a code comment is intended to be used as a fall-through marking. Co-developed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2021-07-11Linux 5.14-rc1v5.14-rc1Linus Torvalds
2021-07-10Merge tag 'kbuild-v5.14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Increase the -falign-functions alignment for the debug option. - Remove ugly libelf checks from the top Makefile. - Make the silent build (-s) more silent. - Re-compile the kernel if KBUILD_BUILD_TIMESTAMP is specified. - Various script cleanups * tag 'kbuild-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (27 commits) scripts: add generic syscallnr.sh scripts: check duplicated syscall number in syscall table sparc: syscalls: use pattern rules to generate syscall headers parisc: syscalls: use pattern rules to generate syscall headers nds32: add arch/nds32/boot/.gitignore kbuild: mkcompile_h: consider timestamp if KBUILD_BUILD_TIMESTAMP is set kbuild: modpost: Explicitly warn about unprototyped symbols kbuild: remove trailing slashes from $(KBUILD_EXTMOD) kconfig.h: explain IS_MODULE(), IS_ENABLED() kconfig: constify long_opts scripts/setlocalversion: simplify the short version part scripts/setlocalversion: factor out 12-chars hash construction scripts/setlocalversion: add more comments to -dirty flag detection scripts/setlocalversion: remove workaround for old make-kpkg scripts/setlocalversion: remove mercurial, svn and git-svn supports kbuild: clean up ${quiet} checks in shell scripts kbuild: sink stdout from cmd for silent build init: use $(call cmd,) for generating include/generated/compile.h kbuild: merge scripts/mkmakefile to top Makefile sh: move core-y in arch/sh/Makefile to arch/sh/Kbuild ...
2021-06-28Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "There's a reasonable amount here and the juicy details are all below. It's worth noting that the MTE/KASAN changes strayed outside of our usual directories due to core mm changes and some associated changes to some other architectures; Andrew asked for us to carry these [1] rather that take them via the -mm tree. Summary: - Optimise SVE switching for CPUs with 128-bit implementations. - Fix output format from SVE selftest. - Add support for versions v1.2 and 1.3 of the SMC calling convention. - Allow Pointer Authentication to be configured independently for kernel and userspace. - PMU driver cleanups for managing IRQ affinity and exposing event attributes via sysfs. - KASAN optimisations for both hardware tagging (MTE) and out-of-line software tagging implementations. - Relax frame record alignment requirements to facilitate 8-byte alignment with KASAN and Clang. - Cleanup of page-table definitions and removal of unused memory types. - Reduction of ARCH_DMA_MINALIGN back to 64 bytes. - Refactoring of our instruction decoding routines and addition of some missing encodings. - Move entry code moved into C and hardened against harmful compiler instrumentation. - Update booting requirements for the FEAT_HCX feature, added to v8.7 of the architecture. - Fix resume from idle when pNMI is being used. - Additional CPU sanity checks for MTE and preparatory changes for systems where not all of the CPUs support 32-bit EL0. - Update our kernel string routines to the latest Cortex Strings implementation. - Big cleanup of our cache maintenance routines, which were confusingly named and inconsistent in their implementations. - Tweak linker flags so that GDB can understand vmlinux when using RELR relocations. - Boot path cleanups to enable early initialisation of per-cpu operations needed by KCSAN. - Non-critical fixes and miscellaneous cleanup" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (150 commits) arm64: tlb: fix the TTL value of tlb_get_level arm64: Restrict undef hook for cpufeature registers arm64/mm: Rename ARM64_SWAPPER_USES_SECTION_MAPS arm64: insn: avoid circular include dependency arm64: smp: Bump debugging information print down to KERN_DEBUG drivers/perf: fix the missed ida_simple_remove() in ddr_perf_probe() perf/arm-cmn: Fix invalid pointer when access dtc object sharing the same IRQ number arm64: suspend: Use cpuidle context helpers in cpu_suspend() PSCI: Use cpuidle context helpers in psci_cpu_suspend_enter() arm64: Convert cpu_do_idle() to using cpuidle context helpers arm64: Add cpuidle context save/restore helpers arm64: head: fix code comments in set_cpu_boot_mode_flag arm64: mm: drop unused __pa(__idmap_text_start) arm64: mm: fix the count comments in compute_indices arm64/mm: Fix ttbr0 values stored in struct thread_info for software-pan arm64: mm: Pass original fault address to handle_mm_fault() arm64/mm: Drop SECTION_[SHIFT|SIZE|MASK] arm64/mm: Use CONT_PMD_SHIFT for ARM64_MEMSTART_SHIFT arm64/mm: Drop SWAPPER_INIT_MAP_SIZE arm64: Conditionally configure PTR_AUTH key of the kernel. ...
2021-06-27Linux 5.13v5.13Linus Torvalds
2021-06-20Linux 5.13-rc7v5.13-rc7Linus Torvalds
2021-06-17kbuild: remove trailing slashes from $(KBUILD_EXTMOD)Masahiro Yamada
M= (or KBUILD_EXTMOD) generally expects a directory path without any trailing slashes, like M=a/b/c. If you add a trailing slash, like M=a/b/c/, you will get ugly build logs (two slashes in a series), but it still works fine as long as it is consistent between 'make modules' and 'make modules_install'. The following commands correctly build and install the modules. $ make M=a/b/c/ modules $ sudo make M=a/b/c/ modules_install Since commit ccae4cfa7bfb ("kbuild: refactor scripts/Makefile.modinst"), a problem happens if you add a trailing slash only for modules_install. $ make M=a/b/c modules $ sudo make M=a/b/c/ modules_install No module is installed in this case, Johannes Berg reported. [1] Trim any trailing slashes from $(KBUILD_EXTMOD). I used the 'dirname' command to remove all the trailing slashes in case someone adds more slashes like M=a/b/c/////. The Make's built-in function, $(dir ...) cannot take care of such a case. [1]: https://lore.kernel.org/lkml/10cc8522b27a051e6a9c3e158a4c4b6414fd04a0.camel@sipsolutions.net/ Fixes: ccae4cfa7bfb ("kbuild: refactor scripts/Makefile.modinst") Reported-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-06-16Merge tag 'clang-features-v5.13-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull clang LTO fix from Kees Cook: "It seems Clang has been scrubbing through the missing LTO IR flags for Clang 13, and the last of these 'only with LTO' flags is fixed now. I've asked that they please consider making these changes in a less 'break all the Clang kernel builds' kind of way in the future. :P Summary: - The '-warn-stack-size' option under LTO has moved in Clang 13 (Tor Vic)" * tag 'clang-features-v5.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: Makefile: lto: Pass -warn-stack-size only on LLD < 13.0.0
2021-06-14Makefile: lto: Pass -warn-stack-size only on LLD < 13.0.0Tor Vic
Since LLVM commit fc018eb, the '-warn-stack-size' flag has been dropped [1], leading to the following error message when building with Clang-13 and LLD-13: ld.lld: error: -plugin-opt=-: ld.lld: Unknown command line argument '-warn-stack-size=2048'. Try: 'ld.lld --help' ld.lld: Did you mean '--asan-stack=2048'? In the same way as with commit 2398ce80152a ("x86, lto: Pass -stack-alignment only on LLD < 13.0.0") , make '-warn-stack-size' conditional on LLD < 13.0.0. [1] https://reviews.llvm.org/D103928 Fixes: 24845dcb170e ("Makefile: LTO: have linker check -Wframe-larger-than") 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> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/7631bab7-a8ab-f884-ab54-f4198976125c@mailbox.org
2021-06-13Linux 5.13-rc6v5.13-rc6Linus Torvalds
2021-06-08Makefile: fix GDB warning with CONFIG_RELRNick Desaulniers
GDB produces the following warning when debugging kernels built with CONFIG_RELR: BFD: /android0/linux-next/vmlinux: unknown type [0x13] section `.relr.dyn' when loading a kernel built with CONFIG_RELR into GDB. It can also prevent debugging symbols using such relocations. Peter sugguests: [That flag] means that lld will use dynamic tags and section type numbers in the OS-specific range rather than the generic range. The kernel itself doesn't care about these numbers; it determines the location of the RELR section using symbols defined by a linker script. Link: https://github.com/ClangBuiltLinux/linux/issues/1057 Suggested-by: Peter Collingbourne <pcc@google.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/r/20210522012626.2811297-1-ndesaulniers@google.com Signed-off-by: Will Deacon <will@kernel.org>
2021-06-06Linux 5.13-rc5v5.13-rc5Linus Torvalds
2021-05-30Linux 5.13-rc4v5.13-rc4Linus Torvalds
2021-05-28Merge tag 'clang-features-v5.13-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull clang feature fixes from Kees Cook: - Correctly pass stack frame size checking under LTO (Nick Desaulniers) - Avoid CFI mismatches by checking initcall_t types (Marco Elver) * tag 'clang-features-v5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: Makefile: LTO: have linker check -Wframe-larger-than init: verify that function is initcall_t at compile-time
2021-05-27kbuild: merge scripts/mkmakefile to top MakefileMasahiro Yamada
scripts/mkmakefile is simple enough to be merged in the Makefile. Use $(call cmd,...) to show the log instead of doing it in the shell script. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-05-26kbuild: require all architectures to have arch/$(SRCARCH)/KbuildMasahiro Yamada
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>
2021-05-24Makefile: LTO: have linker check -Wframe-larger-thanNick Desaulniers
-Wframe-larger-than= requires stack frame information, which the frontend cannot provide. This diagnostic is emitted late during compilation once stack frame size is available. When building with LTO, the frontend simply lowers C to LLVM IR and does not have stack frame information, so it cannot emit this diagnostic. When the linker drives LTO, it restarts optimizations and lowers LLVM IR to object code. At that point, it has stack frame information but doesn't know to check for a specific max stack frame size. I consider this a bug in LLVM that we need to fix. There are some details we're working out related to LTO such as which value to use when there are multiple different values specified per TU, or how to propagate these to compiler synthesized routines properly, if at all. Until it's fixed, ensure we don't miss these. At that point we can wrap this in a compiler version guard or revert this based on the minimum support version of Clang. The error message is not generated during link: LTO vmlinux.o ld.lld: warning: stack size limit exceeded (8224) in foobarbaz Cc: Sami Tolvanen <samitolvanen@google.com> Reported-by: Candle Sun <candlesea@gmail.com> Suggested-by: Fangrui Song <maskray@google.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210312010942.1546679-1-ndesaulniers@google.com
2021-05-24kbuild: remove libelf checks from top MakefileMasahiro Yamada
I do not see a good reason why only the libelf development package must be so carefully checked. Kbuild generally does not check host tools or libraries. For example, x86_64 defconfig fails to build with no libssl development package installed. scripts/extract-cert.c:21:10: fatal error: openssl/bio.h: No such file or directory 21 | #include <openssl/bio.h> | ^~~~~~~~~~~~~~~ To solve the build error, you need to install libssl-dev or openssl-devel package, depending on your distribution. 'apt-file search', 'dnf provides', etc. is your frined to find a proper package to install. This commit removes all the libelf checks from the top Makefile. If libelf is missing, objtool will fail to build in a similar pattern: .../linux/tools/objtool/include/objtool/elf.h:10:10: fatal error: gelf.h: No such file or directory 10 | #include <gelf.h> You need to install libelf-dev, libelf-devel, or elfutils-libelf-devel to proceed. Another remarkable change is, CONFIG_STACK_VALIDATION (without CONFIG_UNWINDER_ORC) previously continued to build with a warning, but now it will treat missing libelf as an error. This is just a one-time installation, so it should not hurt to break a build and make a user install the package. BTW, the traditional way to handle such checks is autotool, but according to [1], I do not expect the kernel build would have similar scripting like './configure' does. [1]: https://lore.kernel.org/lkml/CA+55aFzr2HTZVOuzpHYDwmtRJLsVzE-yqg2DHpHi_9ePsYp5ug@mail.gmail.com/ Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org>
2021-05-24kbuild: hide tools/ build targets from external module buildsMasahiro Yamada
The tools/ directory only exists in the kernel source tree, not in external modules. Do not expose the meaningless targets to external modules. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-05-24Makefile: extend 32B aligned debug option to 64B alignedFeng Tang
Commit 09c60546f04f ("./Makefile: add debug option to enable function aligned on 32 bytes") was introduced to help debugging strange kernel performance changes caused by code alignment change. Recently we found 2 similar cases [1][2] caused by code-alignment changes, which can only be identified by forcing 64 bytes aligned for all functions. Originally, 32 bytes was used mainly for not wasting too much text space, but this option is only for debug anyway where text space is not a big concern. So extend the alignment to 64 bytes to cover more similar cases. [1].https://lore.kernel.org/lkml/20210427090013.GG32408@xsang-OptiPlex-9020/ [2].https://lore.kernel.org/lkml/20210420030837.GB31773@xsang-OptiPlex-9020/ Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-05-23Linux 5.13-rc3v5.13-rc3Linus Torvalds
2021-05-16Linux 5.13-rc2v5.13-rc2Linus Torvalds
2021-05-09Linux 5.13-rc1v5.13-rc1Linus Torvalds
2021-05-08Merge tag 'kbuild-v5.13-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild updates from Masahiro Yamada: - Convert sh and sparc to use generic shell scripts to generate the syscall headers - refactor .gitignore files - Update kernel/config_data.gz only when the content of the .config is really changed, which avoids the unneeded re-link of vmlinux - move "remove stale files" workarounds to scripts/remove-stale-files - suppress unused-but-set-variable warnings by default for Clang as well - fix locale setting LANG=C to LC_ALL=C - improve 'make distclean' - always keep intermediate objects from scripts/link-vmlinux.sh - move IF_ENABLED out of <linux/kconfig.h> to make it self-contained - misc cleanups * tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits) linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h> kbuild: Don't remove link-vmlinux temporary files on exit/signal kbuild: remove the unneeded comments for external module builds kbuild: make distclean remove tag files in sub-directories kbuild: make distclean work against $(objtree) instead of $(srctree) kbuild: refactor modname-multi by using suffix-search kbuild: refactor fdtoverlay rule kbuild: parameterize the .o part of suffix-search arch: use cross_compiling to check whether it is a cross build or not kbuild: remove ARCH=sh64 support from top Makefile .gitignore: prefix local generated files with a slash kbuild: replace LANG=C with LC_ALL=C Makefile: Move -Wno-unused-but-set-variable out of GCC only block kbuild: add a script to remove stale generated files kbuild: update config_data.gz only when the content of .config is changed .gitignore: ignore only top-level modules.builtin .gitignore: move tags and TAGS close to other tag files kernel/.gitgnore: remove stale timeconst.h and hz.bc usr/include: refactor .gitignore genksyms: fix stale comment ...
2021-05-06kbuild: remove the unneeded comments for external module buildsMasahiro Yamada
The supported targets for external modules are listed in the help target a few lines below. Let's not have duplicated information in two places. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-05-06kbuild: make distclean remove tag files in sub-directoriesMasahiro Yamada
'make tags' and friends create tag files in the top directory, but people may manually create tag files in sub-directories. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-05-06kbuild: make distclean work against $(objtree) instead of $(srctree)Masahiro Yamada
This reverts the old commit [1], which seems questionable to me. It claimed 'make distclean' could not remove editor backup files, but I believe KBUILD_OUTPUT or O= was set. When O= is given, Kbuild should always work against $(objtree). If O= is not given, $(objtree) and $(srctree) are the same, therefore $(srctree) is cleaned up. [1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=dd47df980c02eb33833b2690b033c34fba2fa80d Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-05-03kbuild: remove ARCH=sh64 support from top MakefileMasahiro Yamada
Commit 37744feebc08 ("sh: remove sh5 support") removed the SUPERH64 support entirely. Remove the left-over code from the top Makefile. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Arnd Bergmann <arnd@arndb.de>
2021-05-01Merge tag 'integrity-v5.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull IMA updates from Mimi Zohar: "In addition to loading the kernel module signing key onto the builtin keyring, load it onto the IMA keyring as well. Also six trivial changes and bug fixes" * tag 'integrity-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: ima: ensure IMA_APPRAISE_MODSIG has necessary dependencies ima: Fix fall-through warnings for Clang integrity: Add declarations to init_once void arguments. ima: Fix function name error in comment. ima: enable loading of build time generated key on .ima keyring ima: enable signing of modules with build time generated key keys: cleanup build time module signing keys ima: Fix the error code for restoring the PCR value ima: without an IMA policy loaded, return quickly
2021-05-02Makefile: Move -Wno-unused-but-set-variable out of GCC only blockNathan Chancellor
Currently, -Wunused-but-set-variable is only supported by GCC so it is disabled unconditionally in a GCC only block (it is enabled with W=1). clang currently has its implementation for this warning in review so preemptively move this statement out of the GCC only block and wrap it with cc-disable-warning so that both compilers function the same. Cc: stable@vger.kernel.org Link: https://reviews.llvm.org/D100581 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-05-02kbuild: add a script to remove stale generated filesMasahiro Yamada
We maintain .gitignore and Makefiles so build artifacts are properly ignored by Git, and cleaned up by 'make clean'. However, the code is always changing; generated files are often moved to another directory, or removed when they become unnecessary. Such garbage files tend to be left over in the source tree because people usually git-pull without cleaning the tree. This is not only the noise for 'git status', but also a build issue in some cases. One solution is to remove a stale file like commit 223c24a7dba9 ("kbuild: Automatically remove stale <linux/version.h> file") did. Such workaround should be removed after a while, but we forget about that if we scatter the workaround code in random places. So, this commit adds a new script to collect cleanings of stale files. As a start point, move the code in arch/arm/boot/compressed/Makefile into this script. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-29Merge tag 'kconfig-v5.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kconfig updates from Masahiro Yamada: - Change 'option defconfig' to the environment variable KCONFIG_DEFCONFIG_LIST - Refactor tinyconfig without using allnoconfig_y - Remove 'option allnoconfig_y' syntax - Change 'option modules' to 'modules' - Do not use /boot/config-* etc. as base config for cross-compilation - Fix a search bug in nconf - Various code cleanups * tag 'kconfig-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits) kconfig: refactor .gitignore kconfig: highlight xconfig 'comment' lines with '***' kconfig: highlight gconfig 'comment' lines with '***' kconfig: gconf: remove unused code kconfig: remove unused PACKAGE definition kconfig: nconf: stop endless search loops kconfig: split menu.c out of parser.y kconfig: nconf: refactor in print_in_middle() kconfig: nconf: remove meaningless wattrset() call from show_menu() kconfig: nconf: change set_config_filename() to void function kconfig: nconf: refactor attributes setup code kconfig: nconf: remove unneeded default for menu prompt kconfig: nconf: get rid of (void) casts from wattrset() calls kconfig: nconf: fix NORMAL attributes kconfig: mconf,nconf: remove unneeded '\0' termination after snprintf() kconfig: use /boot/config-* etc. as DEFCONFIG_LIST only for native build kconfig: change sym_change_count to a boolean flag kconfig: nconf: fix core dump when searching in empty menu kconfig: lxdialog: A spello fix and a punctuation added kconfig: streamline_config.pl: Couple of typo fixes ...
2021-04-29Merge tag 'kbuild-v5.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild 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 ...
2021-04-27Merge tag 'cfi-v5.13-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull CFI on arm64 support from Kees Cook: "This builds on last cycle's LTO work, and allows the arm64 kernels to be built with Clang's Control Flow Integrity feature. This feature has happily lived in Android kernels for almost 3 years[1], so I'm excited to have it ready for upstream. The wide diffstat is mainly due to the treewide fixing of mismatched list_sort prototypes. Other things in core kernel are to address various CFI corner cases. The largest code portion is the CFI runtime implementation itself (which will be shared by all architectures implementing support for CFI). The arm64 pieces are Acked by arm64 maintainers rather than coming through the arm64 tree since carrying this tree over there was going to be awkward. CFI support for x86 is still under development, but is pretty close. There are a handful of corner cases on x86 that need some improvements to Clang and objtool, but otherwise works well. Summary: - Clean up list_sort prototypes (Sami Tolvanen) - Introduce CONFIG_CFI_CLANG for arm64 (Sami Tolvanen)" * tag 'cfi-v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: arm64: allow CONFIG_CFI_CLANG to be selected KVM: arm64: Disable CFI for nVHE arm64: ftrace: use function_nocfi for ftrace_call arm64: add __nocfi to __apply_alternatives arm64: add __nocfi to functions that jump to a physical address arm64: use function_nocfi with __pa_symbol arm64: implement function_nocfi psci: use function_nocfi for cpu_resume lkdtm: use function_nocfi treewide: Change list_sort to use const pointers bpf: disable CFI in dispatcher functions kallsyms: strip ThinLTO hashes from static functions kthread: use WARN_ON_FUNCTION_MISMATCH workqueue: use WARN_ON_FUNCTION_MISMATCH module: ensure __cfi_check alignment mm: add generic function_nocfi macro cfi: add __cficanonical add support for Clang CFI
2021-04-26Merge tag 'x86-entry-2021-04-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull entry code update from Thomas Gleixner: "Provide support for randomized stack offsets per syscall to make stack-based attacks harder which rely on the deterministic stack layout. The feature is based on the original idea of PaX's RANDSTACK feature, but uses a significantly different implementation. The offset does not affect the pt_regs location on the task stack as this was agreed on to be of dubious value. The offset is applied before the actual syscall is invoked. The offset is stored per cpu and the randomization happens at the end of the syscall which is less predictable than on syscall entry. The mechanism to apply the offset is via alloca(), i.e. abusing the dispised VLAs. This comes with the drawback that stack-clash-protection has to be disabled for the affected compilation units and there is also a negative interaction with stack-protector. Those downsides are traded with the advantage that this approach does not require any intrusive changes to the low level assembly entry code, does not affect the unwinder and the correct stack alignment is handled automatically by the compiler. The feature is guarded with a static branch which avoids the overhead when disabled. Currently this is supported for X86 and ARM64" * tag 'x86-entry-2021-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: arm64: entry: Enable random_kstack_offset support lkdtm: Add REPORT_STACK for checking stack offsets x86/entry: Enable random_kstack_offset support stack: Optionally randomize kernel stack offset each syscall init_on_alloc: Optimize static branches jump_label: Provide CONFIG-driven build state defaults
2021-04-25Linux 5.12v5.12Linus Torvalds
2021-04-25kbuild: Add $(KBUILD_HOSTLDFLAGS) to 'has_libelf' testNathan Chancellor
Normally, invocations of $(HOSTCC) include $(KBUILD_HOSTLDFLAGS), which in turn includes $(HOSTLDFLAGS), which allows users to pass in their own flags when linking. However, the 'has_libelf' test does not, meaning that if a user requests a specific linker via HOSTLDFLAGS=-fuse-ld=..., it is not respected and the build might error. For example, if a user building with clang wants to use all of the LLVM tools without any GNU tools, they might remove all of the GNU tools from their system or PATH then build with $ make HOSTLDFLAGS=-fuse-ld=lld LLVM=1 LLVM_IAS=1 which says use all of the LLVM tools, the integrated assembler, and ld.lld for linking host executables. Without this change, the build will error because $(HOSTCC) uses its default linker, rather than the one requested via -fuse-ld=..., which is GNU ld in clang's case in a default configuration. error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel make[1]: *** [Makefile:1260: prepare-objtool] Error 1 Add $(KBUILD_HOSTLDFLAGS) to the 'has_libelf' test so that the linker choice is respected. Link: https://github.com/ClangBuiltLinux/linux/issues/479 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-25kbuild: merge scripts/Makefile.modsign to scripts/Makefile.modinstMasahiro Yamada
scripts/Makefile.modsign is a subset of scripts/Makefile.modinst, and duplicates the code. Let's merge them. By the way, you do not need to run 'make modules_sign' explicitly because modules are signed as a part of 'make modules_install' when CONFIG_MODULE_SIG_ALL=y. If CONFIG_MODULE_SIG_ALL=n, mod_sign_cmd is set to 'true', so 'make modules_sign' is not functional. In my understanding, the reason of still keeping this is to handle corner cases like commit 64178cb62c32 ("builddeb: fix stripped module signatures if CONFIG_DEBUG_INFO and CONFIG_MODULE_SIG_ALL are set"). Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-25kbuild: move module strip/compression code into scripts/Makefile.modinstMasahiro Yamada
Both mod_strip_cmd and mod_compress_cmd are only used in scripts/Makefile.modinst, hence there is no good reason to define them in the top Makefile. Move the relevant code to scripts/Makefile.modinst. Also, show separate log messages for each of install, strip, sign, and compress. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-25kbuild: refactor scripts/Makefile.modinstMasahiro Yamada
scripts/Makefile.modinst is ugly and weird in multiple ways; it specifies real files $(modules) as phony, makes directory manipulation needlessly too complicated. Clean up the Makefile code, and show the full path of installed modules in the log. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-25kbuild: rename extmod-prefix to extmod_prefixMasahiro Yamada
This seems to be useful in sub-make as well. As a preparation of exporting it, rename extmod-prefix to extmod_prefix because exported variables cannot contain hyphens. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2021-04-25kbuild: check module name conflict for external modules as wellMasahiro Yamada
If there are multiple modules with the same name in the same external module tree, there is ambiguity about which one will be loaded, and very likely something odd is happening. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-25kbuild: show the target directory for depmod logMasahiro Yamada
It is clearer to show the directory which depmod will work on. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-25kbuild: unify modules(_install) for in-tree and external modulesMasahiro Yamada
If you attempt to build or install modules ('make modules(_install)' with CONFIG_MODULES disabled, you will get a clear error message, but nothing for external module builds. Factor out the modules and modules_install rules into the common part, so you will get the same error message when you try to build external modules with CONFIG_MODULES=n. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-25kbuild: remove unneeded mkdir for external modules_installMasahiro Yamada
scripts/Makefile.modinst creates directories as needed. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-04-25kbuild: generate Module.symvers only when vmlinux existsMasahiro Yamada
The external module build shows the following warning if Module.symvers is missing in the kernel tree. WARNING: Symbol version dump "Module.symvers" is missing. Modules may not have dependencies or modversions. I think this is an important heads-up because the resulting modules may not work as expected. This happens when you did not build the entire kernel tree, for example, you might have prepared the minimal setups for external modules by 'make defconfig && make modules_preapre'. A problem is that 'make modules' creates Module.symvers even without vmlinux. In this case, that warning is suppressed since Module.symvers already exists in spite of its incomplete content. The incomplete (i.e. invalid) Module.symvers should not be created. This commit changes the second pass of modpost to dump symbols into modules-only.symvers. The final Module.symvers is created by concatenating vmlinux.symvers and modules-only.symvers if both exist. Module.symvers is supposed to collect symbols from both vmlinux and modules. It might be a bit confusing, and I am not quite sure if it is an official interface, but presumably it is difficult to rename it because some tools (e.g. kmod) parse it. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>