The patch titled Subject: kmsan: disable instrumentation of unsupported common kernel code has been added to the -mm mm-unstable branch. Its filename is kmsan-disable-instrumentation-of-unsupported-common-kernel-code.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kmsan-disable-instrumentation-of-unsupported-common-kernel-code.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Alexander Potapenko <glider@xxxxxxxxxx> Subject: kmsan: disable instrumentation of unsupported common kernel code Date: Mon, 5 Sep 2022 14:24:20 +0200 EFI stub cannot be linked with KMSAN runtime, so we disable instrumentation for it. Instrumenting kcov, stackdepot or lockdep leads to infinite recursion caused by instrumentation hooks calling instrumented code again. Link: https://lkml.kernel.org/r/20220905122452.2258262-13-glider@xxxxxxxxxx Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx> Reviewed-by: Marco Elver <elver@xxxxxxxxxx> Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Alexei Starovoitov <ast@xxxxxxxxxx> Cc: Andrey Konovalov <andreyknvl@xxxxxxxxx> Cc: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Eric Biggers <ebiggers@xxxxxxxxxx> Cc: Eric Dumazet <edumazet@xxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Cc: Ilya Leoshkevich <iii@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Jens Axboe <axboe@xxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Liu Shixin <liushixin2@xxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Michael S. Tsirkin <mst@xxxxxxxxxx> Cc: Pekka Enberg <penberg@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Petr Mladek <pmladek@xxxxxxxx> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Cc: Vegard Nossum <vegard.nossum@xxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/firmware/efi/libstub/Makefile | 1 + kernel/Makefile | 1 + kernel/locking/Makefile | 3 ++- lib/Makefile | 3 +++ 4 files changed, 7 insertions(+), 1 deletion(-) --- a/drivers/firmware/efi/libstub/Makefile~kmsan-disable-instrumentation-of-unsupported-common-kernel-code +++ a/drivers/firmware/efi/libstub/Makefile @@ -46,6 +46,7 @@ GCOV_PROFILE := n # Sanitizer runtimes are unavailable and cannot be linked here. KASAN_SANITIZE := n KCSAN_SANITIZE := n +KMSAN_SANITIZE := n UBSAN_SANITIZE := n OBJECT_FILES_NON_STANDARD := y --- a/kernel/locking/Makefile~kmsan-disable-instrumentation-of-unsupported-common-kernel-code +++ a/kernel/locking/Makefile @@ -5,8 +5,9 @@ KCOV_INSTRUMENT := n obj-y += mutex.o semaphore.o rwsem.o percpu-rwsem.o -# Avoid recursion lockdep -> KCSAN -> ... -> lockdep. +# Avoid recursion lockdep -> sanitizer -> ... -> lockdep. KCSAN_SANITIZE_lockdep.o := n +KMSAN_SANITIZE_lockdep.o := n ifdef CONFIG_FUNCTION_TRACER CFLAGS_REMOVE_lockdep.o = $(CC_FLAGS_FTRACE) --- a/kernel/Makefile~kmsan-disable-instrumentation-of-unsupported-common-kernel-code +++ a/kernel/Makefile @@ -38,6 +38,7 @@ KCOV_INSTRUMENT_kcov.o := n KASAN_SANITIZE_kcov.o := n KCSAN_SANITIZE_kcov.o := n UBSAN_SANITIZE_kcov.o := n +KMSAN_SANITIZE_kcov.o := n CFLAGS_kcov.o := $(call cc-option, -fno-conserve-stack) -fno-stack-protector # Don't instrument error handlers --- a/lib/Makefile~kmsan-disable-instrumentation-of-unsupported-common-kernel-code +++ a/lib/Makefile @@ -275,6 +275,9 @@ obj-$(CONFIG_POLYNOMIAL) += polynomial.o CFLAGS_stackdepot.o += -fno-builtin obj-$(CONFIG_STACKDEPOT) += stackdepot.o KASAN_SANITIZE_stackdepot.o := n +# In particular, instrumenting stackdepot.c with KMSAN will result in infinite +# recursion. +KMSAN_SANITIZE_stackdepot.o := n KCOV_INSTRUMENT_stackdepot.o := n obj-$(CONFIG_REF_TRACKER) += ref_tracker.o _ Patches currently in -mm which might be from glider@xxxxxxxxxx are stackdepot-reserve-5-extra-bits-in-depot_stack_handle_t.patch instrumentedh-allow-instrumenting-both-sides-of-copy_from_user.patch x86-asm-instrument-usercopy-in-get_user-and-put_user.patch asm-generic-instrument-usercopy-in-cacheflushh.patch kmsan-add-rest-documentation.patch kmsan-introduce-__no_sanitize_memory-and-__no_kmsan_checks.patch kmsan-mark-noinstr-as-__no_sanitize_memory.patch x86-kmsan-pgtable-reduce-vmalloc-space.patch libnvdimm-pfn_dev-increase-max_struct_page_size.patch kmsan-add-kmsan-runtime-core.patch kmsan-disable-instrumentation-of-unsupported-common-kernel-code.patch maintainers-add-entry-for-kmsan.patch mm-kmsan-maintain-kmsan-metadata-for-page-operations.patch mm-kmsan-call-kmsan-hooks-from-slub-code.patch kmsan-handle-task-creation-and-exiting.patch init-kmsan-call-kmsan-initialization-routines.patch instrumentedh-add-kmsan-support.patch kmsan-unpoison-tlb-in-arch_tlb_gather_mmu.patch kmsan-add-iomap-support.patch input-libps2-mark-data-received-in-__ps2_command-as-initialized.patch dma-kmsan-unpoison-dma-mappings.patch virtio-kmsan-check-unpoison-scatterlist-in-vring_map_one_sg.patch kmsan-handle-memory-sent-to-from-usb.patch kmsan-add-tests-for-kmsan.patch kmsan-disable-strscpy-optimization-under-kmsan.patch crypto-kmsan-disable-accelerated-configs-under-kmsan.patch kmsan-disable-physical-page-merging-in-biovec.patch block-kmsan-skip-bio-block-merging-logic-for-kmsan.patch kcov-kmsan-unpoison-area-list-in-kcov_remote_area_put.patch security-kmsan-fix-interoperability-with-auto-initialization.patch objtool-kmsan-list-kmsan-api-functions-as-uaccess-safe.patch x86-kmsan-disable-instrumentation-of-unsupported-code.patch x86-kmsan-skip-shadow-checks-in-__switch_to.patch x86-kmsan-handle-open-coded-assembly-in-lib-iomemc.patch x86-kmsan-use-__msan_-string-functions-where-possible.patch x86-kmsan-sync-metadata-pages-on-page-fault.patch x86-kasan-kmsan-support-config_generic_csum-on-x86-enable-it-for-kasan-kmsan.patch x86-fs-kmsan-disable-config_dcache_word_access.patch entry-kmsan-introduce-kmsan_unpoison_entry_regs.patch bpf-kmsan-initialize-bpf-registers-with-zeroes.patch mm-fs-initialize-fsdata-passed-to-write_begin-write_end-interface.patch x86-kmsan-enable-kmsan-builds-for-x86.patch