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2022-09-21arch: um: Mark the stack non-executable to fix a binutils warningDavid Gow1-1/+1
Since binutils 2.39, ld will print a warning if any stack section is executable, which is the default for stack sections on files without a .note.GNU-stack section. This was fixed for x86 in commit ffcf9c5700e4 ("x86: link vdso and boot with -z noexecstack --no-warn-rwx-segments"), but remained broken for UML, resulting in several warnings: /usr/bin/ld: warning: arch/x86/um/vdso/vdso.o: missing .note.GNU-stack section implies executable stack /usr/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker /usr/bin/ld: warning: .tmp_vmlinux.kallsyms1 has a LOAD segment with RWX permissions /usr/bin/ld: warning: .tmp_vmlinux.kallsyms1.o: missing .note.GNU-stack section implies executable stack /usr/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker /usr/bin/ld: warning: .tmp_vmlinux.kallsyms2 has a LOAD segment with RWX permissions /usr/bin/ld: warning: .tmp_vmlinux.kallsyms2.o: missing .note.GNU-stack section implies executable stack /usr/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker /usr/bin/ld: warning: vmlinux has a LOAD segment with RWX permissions Link both the VDSO and vmlinux with -z noexecstack, fixing the warnings about .note.GNU-stack sections. In addition, pass --no-warn-rwx-segments to dodge the remaining warnings about LOAD segments with RWX permissions in the kallsyms objects. (Note that this flag is apparently not available on lld, so hide it behind a test for BFD, which is what the x86 patch does.) Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ffcf9c5700e49c0aee42dcba9a12ba21338e8136 Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=ba951afb99912da01a6e8434126b8fac7aa75107 Signed-off-by: David Gow <davidgow@google.com> Reviewed-by: Lukas Straub <lukasstraub2@web.de> Tested-by: Lukas Straub <lukasstraub2@web.de> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-19um: Cleanup compiler warning in arch/x86/um/tls_32.cLukas Straub1-6/+0
arch.tls_array is statically allocated so checking for NULL doesn't make sense. This causes the compiler warning below. Remove the checks to silence these warnings. ../arch/x86/um/tls_32.c: In function 'get_free_idx': ../arch/x86/um/tls_32.c:68:13: warning: the comparison will always evaluate as 'true' for the address of 'tls_array' will never be NULL [-Waddress] 68 | if (!t->arch.tls_array) | ^ In file included from ../arch/x86/um/asm/processor.h:10, from ../include/linux/rcupdate.h:30, from ../include/linux/rculist.h:11, from ../include/linux/pid.h:5, from ../include/linux/sched.h:14, from ../arch/x86/um/tls_32.c:7: ../arch/x86/um/asm/processor_32.h:22:31: note: 'tls_array' declared here 22 | struct uml_tls_struct tls_array[GDT_ENTRY_TLS_ENTRIES]; | ^~~~~~~~~ ../arch/x86/um/tls_32.c: In function 'get_tls_entry': ../arch/x86/um/tls_32.c:243:13: warning: the comparison will always evaluate as 'true' for the address of 'tls_array' will never be NULL [-Waddress] 243 | if (!t->arch.tls_array) | ^ ../arch/x86/um/asm/processor_32.h:22:31: note: 'tls_array' declared here 22 | struct uml_tls_struct tls_array[GDT_ENTRY_TLS_ENTRIES]; | ^~~~~~~~~ Signed-off-by: Lukas Straub <lukasstraub2@web.de> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Signed-off-by: Richard Weinberger <richard@nod.at>
2022-09-19um: Cleanup syscall_handler_t cast in syscalls_32.hLukas Straub1-3/+2
Like in f4f03f299a56ce4d73c5431e0327b3b6cb55ebb9 "um: Cleanup syscall_handler_t definition/cast, fix warning", remove the cast to to fix the compiler warning. Signed-off-by: Lukas Straub <lukasstraub2@web.de> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Signed-off-by: Richard Weinberger <richard@nod.at>
2022-08-06Merge tag 'x86-urgent-2022-08-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-1/+2
Pull x86 fixes from Ingo Molnar: - build fix for old(er) binutils - build fix for new GCC - kexec boot environment fix * tag 'x86-urgent-2022-08-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/entry: Build thunk_$(BITS) only if CONFIG_PREEMPTION=y x86/numa: Use cpumask_available instead of hardcoded NULL check x86/bus_lock: Don't assume the init value of DEBUGCTLMSR.BUS_LOCK_DETECT to be zero
2022-08-05Merge tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mmLinus Torvalds1-1/+1
Pull MM updates from Andrew Morton: "Most of the MM queue. A few things are still pending. Liam's maple tree rework didn't make it. This has resulted in a few other minor patch series being held over for next time. Multi-gen LRU still isn't merged as we were waiting for mapletree to stabilize. The current plan is to merge MGLRU into -mm soon and to later reintroduce mapletree, with a view to hopefully getting both into 6.1-rc1. Summary: - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe Lin, Yang Shi, Anshuman Khandual and Mike Rapoport - Some kmemleak fixes from Patrick Wang and Waiman Long - DAMON updates from SeongJae Park - memcg debug/visibility work from Roman Gushchin - vmalloc speedup from Uladzislau Rezki - more folio conversion work from Matthew Wilcox - enhancements for coherent device memory mapping from Alex Sierra - addition of shared pages tracking and CoW support for fsdax, from Shiyang Ruan - hugetlb optimizations from Mike Kravetz - Mel Gorman has contributed some pagealloc changes to improve latency and realtime behaviour. - mprotect soft-dirty checking has been improved by Peter Xu - Many other singleton patches all over the place" [ XFS merge from hell as per Darrick Wong in https://lore.kernel.org/all/YshKnxb4VwXycPO8@magnolia/ ] * tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (282 commits) tools/testing/selftests/vm/hmm-tests.c: fix build mm: Kconfig: fix typo mm: memory-failure: convert to pr_fmt() mm: use is_zone_movable_page() helper hugetlbfs: fix inaccurate comment in hugetlbfs_statfs() hugetlbfs: cleanup some comments in inode.c hugetlbfs: remove unneeded header file hugetlbfs: remove unneeded hugetlbfs_ops forward declaration hugetlbfs: use helper macro SZ_1{K,M} mm: cleanup is_highmem() mm/hmm: add a test for cross device private faults selftests: add soft-dirty into run_vmtests.sh selftests: soft-dirty: add test for mprotect mm/mprotect: fix soft-dirty check in can_change_pte_writable() mm: memcontrol: fix potential oom_lock recursion deadlock mm/gup.c: fix formatting in check_and_migrate_movable_page() xfs: fail dax mount if reflink is enabled on a partition mm/memcontrol.c: remove the redundant updating of stats_flush_threshold userfaultfd: don't fail on unrecognized features hugetlb_cgroup: fix wrong hugetlb cgroup numa stat ...
2022-08-04x86/entry: Build thunk_$(BITS) only if CONFIG_PREEMPTION=yAndrea Righi1-1/+2
With CONFIG_PREEMPTION disabled, arch/x86/entry/thunk_$(BITS).o becomes an empty object file. With some old versions of binutils (i.e., 2.35.90.20210113-1ubuntu1) the GNU assembler doesn't generate a symbol table for empty object files and objtool fails with the following error when a valid symbol table cannot be found: arch/x86/entry/thunk_64.o: warning: objtool: missing symbol table To prevent this from happening, build thunk_$(BITS).o only if CONFIG_PREEMPTION is enabled. BugLink: https://bugs.launchpad.net/bugs/1911359 Fixes: 320100a5ffe5 ("x86/entry: Remove the TRACE_IRQS cruft") Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/Ys/Ke7EWjcX+ZlXO@arighi-desktop
2022-07-17um/mm: enable ARCH_HAS_VM_GET_PAGE_PROTAnshuman Khandual1-1/+1
This enables ARCH_HAS_VM_GET_PAGE_PROT on the platform and exports standard vm_get_page_prot() implementation via DECLARE_VM_GET_PAGE_PROT, which looks up a private and static protection_map[] array. Subsequently all __SXXX and __PXXX macros can be dropped which are no longer needed. Link: https://lkml.kernel.org/r/20220711070600.2378316-25-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Brian Cain <bcain@quicinc.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Christoph Hellwig <hch@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@kernel.org> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17um: include linux/stddef.h for __always_inlineJason A. Donenfeld1-0/+1
When compiling against musl, their shipped <stddef.h> doesn't have __always_inline. So instead explicitly include the kernel uapi header, <linux/stddef.h>, which does. This prevents the following build error: In file included from arch/x86/um/shared/sysdep/stub.h:11, from arch/um/kernel/skas/clone.c:14: arch/x86/um/shared/sysdep/stub_64.h:111:23: error: expected ‘;’ before ‘void’ 111 | static __always_inline void *get_stub_page(void) | ^~~~~ | ; make[4]: *** [scripts/Makefile.build:249: arch/um/kernel/skas/clone.o] Error 1 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2022-07-17UML: add support for KASAN under x86_64Patricia Alfonso2-1/+5
Make KASAN run on User Mode Linux on x86_64. The UML-specific KASAN initializer uses mmap to map the ~16TB of shadow memory to the location defined by KASAN_SHADOW_OFFSET. kasan_init() utilizes constructors to initialize KASAN before main(). The location of the KASAN shadow memory, starting at KASAN_SHADOW_OFFSET, can be configured using the KASAN_SHADOW_OFFSET option. The default location of this offset is 0x100000000000, which keeps it out-of-the-way even on UML setups with more "physical" memory. For low-memory setups, 0x7fff8000 can be used instead, which fits in an immediate and is therefore faster, as suggested by Dmitry Vyukov. There is usually enough free space at this location; however, it is a config option so that it can be easily changed if needed. Note that, unlike KASAN on other architectures, vmalloc allocations still use the shadow memory allocated upfront, rather than allocating and free-ing it per-vmalloc allocation. If another architecture chooses to go down the same path, we should replace the checks for CONFIG_UML with something more generic, such as: - A CONFIG_KASAN_NO_SHADOW_ALLOC option, which architectures could set - or, a way of having architecture-specific versions of these vmalloc and module shadow memory allocation options. Also note that, while UML supports both KASAN in inline mode (CONFIG_KASAN_INLINE) and static linking (CONFIG_STATIC_LINK), it does not support both at the same time. Signed-off-by: Patricia Alfonso <trishalfonso@google.com> Co-developed-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: David Gow <davidgow@google.com> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2022-07-17um: x86: print RIP with symbolJohannes Berg1-2/+2
This is not only nicer to read by default, but also lets decode_stacktrace.sh work on it, rather than removing it. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2022-07-17x86/um: Kconfig: Fix indentationJuerg Haefliger1-5/+5
The convention for indentation seems to be a single tab. Help text is further indented by an additional two whitespaces. Fix the lines that violate these rules. Signed-off-by: Juerg Haefliger <juerg.haefliger@canonical.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2022-05-27um: Fix out-of-bounds read in LDT setupVincent Whitchurch1-2/+4
syscall_stub_data() expects the data_count parameter to be the number of longs, not bytes. ================================================================== BUG: KASAN: stack-out-of-bounds in syscall_stub_data+0x70/0xe0 Read of size 128 at addr 000000006411f6f0 by task swapper/1 CPU: 0 PID: 1 Comm: swapper Not tainted 5.18.0+ #18 Call Trace: show_stack.cold+0x166/0x2a7 __dump_stack+0x3a/0x43 dump_stack_lvl+0x1f/0x27 print_report.cold+0xdb/0xf81 kasan_report+0x119/0x1f0 kasan_check_range+0x3a3/0x440 memcpy+0x52/0x140 syscall_stub_data+0x70/0xe0 write_ldt_entry+0xac/0x190 init_new_ldt+0x515/0x960 init_new_context+0x2c4/0x4d0 mm_init.constprop.0+0x5ed/0x760 mm_alloc+0x118/0x170 0x60033f48 do_one_initcall+0x1d7/0x860 0x60003e7b kernel_init+0x6e/0x3d4 new_thread_handler+0x1e7/0x2c0 The buggy address belongs to stack of task swapper/1 and is located at offset 64 in frame: init_new_ldt+0x0/0x960 This frame has 2 objects: [32, 40) 'addr' [64, 80) 'desc' ================================================================== Fixes: 858259cf7d1c443c83 ("uml: maintain own LDT entries") Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Cc: stable@vger.kernel.org Signed-off-by: Richard Weinberger <richard@nod.at>
2022-04-01Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds1-0/+1
Pull vfs updates from Al Viro: "Assorted bits and pieces" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: aio: drop needless assignment in aio_read() clean overflow checks in count_mounts() a bit seq_file: fix NULL pointer arithmetic warning uml/x86: use x86 load_unaligned_zeropad() asm/user.h: killed unused macros constify struct path argument of finish_automount()/do_add_mount() fs: Remove FIXME comment in generic_write_checks()
2022-03-31Merge tag 'for-linus-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/umlLinus Torvalds2-4/+2
Pull UML updates from Richard Weinberger: - Devicetree support (for testing) - Various cleanups and fixes: UBD, port_user, uml_mconsole - Maintainer update * tag 'for-linus-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: run_helper: Write error message to kernel log on exec failure on host um: port_user: Improve error handling when port-helper is not found um: port_user: Allow setting path to port-helper using UML_PORT_HELPER envvar um: port_user: Search for in.telnetd in PATH um: clang: Strip out -mno-global-merge from USER_CFLAGS docs: UML: Mention telnetd for port channel um: Remove unused timeval_to_ns() function um: Fix uml_mconsole stop/go um: Cleanup syscall_handler_t definition/cast, fix warning uml: net: vector: fix const issue um: Fix WRITE_ZEROES in the UBD Driver um: Migrate vector drivers to NAPI um: Fix order of dtb unflatten/early init um: fix and optimize xor select template for CONFIG64 and timetravel mode um: Document dtb command line option lib/logic_iomem: correct fallback config references um: Remove duplicated include in syscalls_64.c MAINTAINERS: Update UserModeLinux entry
2022-03-21Merge tag 'overflow-v5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linuxLinus Torvalds1-5/+4
Pull overflow updates from Kees Cook: "These changes come in roughly two halves: support of Gustavo A. R. Silva's struct_size() work via additional helpers for catching overflow allocation size calculations, and conversions of selftests to KUnit (which includes some tweaks for UML + Clang): - Convert overflow selftest to KUnit - Convert stackinit selftest to KUnit - Implement size_t saturating arithmetic helpers - Allow struct_size() to be used in initializers" * tag 'overflow-v5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: lib: stackinit: Convert to KUnit um: Allow builds with Clang lib: overflow: Convert to Kunit overflow: Provide constant expression struct_size overflow: Implement size_t saturating arithmetic helpers test_overflow: Regularize test reporting output
2022-03-21um: Allow builds with ClangKees Cook1-5/+4
Add SUBARCH target for Clang+um (which must go last, not alphabetically, so the other SUBARCHes are assigned). Remove open-coded "DEFINE" macro, instead using linux/kbuild.h's version which was updated to use Clang-friendly assembly in commit cf0c3e68aa81 ("kbuild: fix asm-offset generation to work with clang"). Redefine "DEFINE_LONGS" in terms of "COMMENT" and "DEFINE" so that the intended coment actually has useful content. Add a missed "break" to avoid implicit fall-through warnings. This lets me run KUnit tests with Clang: $ ./tools/testing/kunit/kunit.py run --make_options LLVM=1 ... Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: David Gow <davidgow@google.com> Cc: linux-um@lists.infradead.org Cc: linux-kbuild@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Cc: kunit-dev@googlegroups.com Cc: llvm@lists.linux.dev Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/lkml/Yg2YubZxvYvx7%2Fnm@dev-arch.archlinux-ax161/ Tested-by: David Gow <davidgow@google.com> Link: https://lore.kernel.org/lkml/CABVgOSk=oFxsbSbQE-v65VwR2+mXeGXDDjzq8t7FShwjJ3+kUg@mail.gmail.com/ Signed-off-by: Kees Cook <keescook@chromium.org> --- v1: https://lore.kernel.org/lkml/20220217002843.2312603-1-keescook@chromium.org v2: https://lore.kernel.org/lkml/20220224055831.1854786-1-keescook@chromium.org v3: - use kbuild.h to avoid duplication (Masahiro) - fix intended comments (Masahiro) - use SUBARCH (Nathan)
2022-03-11um: Cleanup syscall_handler_t definition/cast, fix warningDavid Gow1-3/+2
The syscall_handler_t type for x86_64 was defined as 'long (*)(void)', but always cast to 'long (*)(long, long, long, long, long, long)' before use. This now triggers a warning (see below). Define syscall_handler_t as the latter instead, and remove the cast. This simplifies the code, and fixes the warning. Warning: In file included from ../arch/um/include/asm/processor-generic.h:13 from ../arch/x86/um/asm/processor.h:41 from ../include/linux/rcupdate.h:30 from ../include/linux/rculist.h:11 from ../include/linux/pid.h:5 from ../include/linux/sched.h:14 from ../include/linux/ptrace.h:6 from ../arch/um/kernel/skas/syscall.c:7: ../arch/um/kernel/skas/syscall.c: In function ‘handle_syscall’: ../arch/x86/um/shared/sysdep/syscalls_64.h:18:11: warning: cast between incompatible function types from ‘long int (*)(void)’ to ‘long int (*)(long int, long int, long int, long int, long int, long int)’ [ -Wcast-function-type] 18 | (((long (*)(long, long, long, long, long, long)) \ | ^ ../arch/x86/um/asm/ptrace.h:36:62: note: in definition of macro ‘PT_REGS_SET_SYSCALL_RETURN’ 36 | #define PT_REGS_SET_SYSCALL_RETURN(r, res) (PT_REGS_AX(r) = (res)) | ^~~ ../arch/um/kernel/skas/syscall.c:46:33: note: in expansion of macro ‘EXECUTE_SYSCALL’ 46 | EXECUTE_SYSCALL(syscall, regs)); | ^~~~~~~~~~~~~~~ Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2022-03-11um: Remove duplicated include in syscalls_64.cYang Li1-1/+0
Fix following includecheck warning: ./arch/x86/um/syscalls_64.c: registers.h is included more than once. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Fixes: dbba7f704aa0 ("um: stop polluting the namespace with registers.h contents") Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2022-02-15elfcore: Replace CONFIG_{IA64, UML} checks with a new optionCatalin Marinas1-0/+1
As arm64 is about to introduce MTE-specific phdrs in the core dump, add a common CONFIG_ARCH_BINFMT_ELF_EXTRA_PHDRS option currently selectable by UML_X86 and IA64. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Eric Biederman <ebiederm@xmission.com> Link: https://lore.kernel.org/r/20220131165456.2160675-2-catalin.marinas@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-01-30uml/x86: use x86 load_unaligned_zeropad()Al Viro1-0/+1
allows, among other things, to drop !DCACHE_WORD_ACCESS mess in x86 csum-partial_64.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-01-23Merge tag 'bitmap-5.17-rc1' of git://github.com/norov/linuxLinus Torvalds1-1/+0
Pull bitmap updates from Yury Norov: - introduce for_each_set_bitrange() - use find_first_*_bit() instead of find_next_*_bit() where possible - unify for_each_bit() macros * tag 'bitmap-5.17-rc1' of git://github.com/norov/linux: vsprintf: rework bitmap_list_string lib: bitmap: add performance test for bitmap_print_to_pagebuf bitmap: unify find_bit operations mm/percpu: micro-optimize pcpu_is_populated() Replace for_each_*_bit_from() with for_each_*_bit() where appropriate find: micro-optimize for_each_{set,clear}_bit() include/linux: move for_each_bit() macros from bitops.h to find.h cpumask: replace cpumask_next_* with cpumask_first_* where appropriate tools: sync tools/bitmap with mother linux all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate cpumask: use find_first_and_bit() lib: add find_first_and_bit() arch: remove GENERIC_FIND_FIRST_BIT entirely include: move find.h from asm_generic to linux bitops: move find_bit_*_le functions from le.h to find.h bitops: protect find_first_{,zero}_bit properly
2022-01-15arch: remove GENERIC_FIND_FIRST_BIT entirelyYury Norov1-1/+0
In 5.12 cycle we enabled GENERIC_FIND_FIRST_BIT config option for ARM64 and MIPS. It increased performance and shrunk .text size; and so far I didn't receive any negative feedback on the change. https://lore.kernel.org/linux-arch/20210225135700.1381396-1-yury.norov@gmail.com/ Now I think it's a good time to switch all architectures to use find_{first,last}_bit() unconditionally, and so remove corresponding config option. The patch does't introduce functioal changes for arc, arm, arm64, mips, m68k, s390 and x86, for other architectures I expect improvement both in performance and .text size. Signed-off-by: Yury Norov <yury.norov@gmail.com> Tested-by: Alexander Lobakin <alobakin@pm.me> (mips) Reviewed-by: Alexander Lobakin <alobakin@pm.me> (mips) Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Will Deacon <will@kernel.org> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2022-01-12Merge tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds3-4/+4
Pull x86 core updates from Borislav Petkov: - Get rid of all the .fixup sections because this generates misleading/wrong stacktraces and confuse RELIABLE_STACKTRACE and LIVEPATCH as the backtrace misses the function which is being fixed up. - Add Straight Line Speculation mitigation support which uses a new compiler switch -mharden-sls= which sticks an INT3 after a RET or an indirect branch in order to block speculation after them. Reportedly, CPUs do speculate behind such insns. - The usual set of cleanups and improvements * tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits) x86/entry_32: Fix segment exceptions objtool: Remove .fixup handling x86: Remove .fixup section x86/word-at-a-time: Remove .fixup usage x86/usercopy: Remove .fixup usage x86/usercopy_32: Simplify __copy_user_intel_nocache() x86/sgx: Remove .fixup usage x86/checksum_32: Remove .fixup usage x86/vmx: Remove .fixup usage x86/kvm: Remove .fixup usage x86/segment: Remove .fixup usage x86/fpu: Remove .fixup usage x86/xen: Remove .fixup usage x86/uaccess: Remove .fixup usage x86/futex: Remove .fixup usage x86/msr: Remove .fixup usage x86/extable: Extend extable functionality x86/entry_32: Remove .fixup usage x86/entry_64: Remove .fixup usage x86/copy_mc_64: Remove .fixup usage ...
2021-12-22um: remove set_fsChristoph Hellwig1-8/+0
Remove address space overrides using set_fs() for User Mode Linux. Note that just like the existing kernel access case of the uaccess routines the new nofault kernel handlers do not actually have any exception handling. This is probably broken, but not change to the status quo. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21uml/i386: missing include in barrier.hAl Viro1-0/+1
we need cpufeatures.h there Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21um: stop polluting the namespace with registers.h contentsAl Viro5-0/+5
Only one extern in there is needed in processor-generic.h, and it's not needed anywhere else. So move it over there and get rid of the include in processor-generic.h, adding includes of registers.h to the few files that need the declarations in it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21um: move amd64 variant of mmap(2) to arch/x86/um/syscalls_64.cAl Viro3-6/+10
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21uml: trim unused junk from arch/x86/um/sys_call_table_*.cAl Viro2-18/+0
a bunch of detritus there - definitions that are never expanded or checked. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21um: registers: Rename function names to avoid conflicts and build problemsRandy Dunlap1-1/+2
The function names init_registers() and restore_registers() are used in several net/ethernet/ and gpu/drm/ drivers for other purposes (not calls to UML functions), so rename them. This fixes multiple build errors. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: linux-um@lists.infradead.org Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-21uml: x86: add FORCE to user_constants.hJohannes Berg1-1/+1
The build system has started warning when filechk is called without FORCE: arch/x86/um/Makefile:44: FORCE prerequisite is missing Add FORCE to make sure the file is checked/rebuilt when necessary (and to quiet up the warning.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: David Gow <davidgow@google.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-12-08x86: Prepare asm files for straight-line-speculationPeter Zijlstra3-4/+4
Replace all ret/retq instructions with RET in preparation of making RET a macro. Since AS is case insensitive it's a big no-op without RET defined. find arch/x86/ -name \*.S | while read file do sed -i 's/\<ret[q]*\>/RET/' $file done Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20211204134907.905503893@infradead.org
2021-08-26um: fix stub location calculationJohannes Berg3-2/+25
In commit 9f0b4807a44f ("um: rework userspace stubs to not hard-code stub location") I changed stub_segv_handler() to do a calculation with a pointer to a stack variable to find the data page that we're using for the stack and the rest of the data. This same commit was meant to do it as well for stub_clone_handler(), but the change inadvertently went into commit 84b2789d6115 ("um: separate child and parent errors in clone stub") instead. This was reported to not be compiled correctly by gcc 5, causing the code to crash here. I'm not sure why, perhaps it's UB because the var isn't initialized? In any case, this trick always seemed bad, so just create a new inline function that does the calculation in assembly. Reported-by: subashab@codeaurora.org Fixes: 9f0b4807a44f ("um: rework userspace stubs to not hard-code stub location") Fixes: 84b2789d6115 ("um: separate child and parent errors in clone stub") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-05-25x86/uml/syscalls: Remove array index from syscall initializersBrian Gerst2-2/+2
The recent syscall table generator rework removed the index from the initializers for native x86 syscall tables, but missed the UML syscall tables. Fixes: 44fe4895f47c ("Stop filling syscall arrays with *_sys_ni_syscall") Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Masahiro Yamada <masahiroy@kernel.org> Link: https://lore.kernel.org/r/20210524181707.132844-2-brgerst@gmail.com
2021-05-20x86/syscalls: Stop filling syscall arrays with *_sys_ni_syscallMasahiro Yamada2-12/+0
This is a follow-up cleanup after switching to the generic syscalltbl.sh. The old x86 specific script skipped non-existing syscalls. So, the generated syscalls_64.h, for example, had a big hole in the syscall numbers 335-423 range. That is why there exists [0 ... __NR_*_syscall_max] = &__*_sys_ni_cyscall. The new script, scripts/syscalltbl.sh automatically fills holes with __SYSCALL(<nr>, sys_ni_syscall), hence such ugly code can go away. The designated initializers, '[nr] =' are also unneeded. Also, there is no need to give __NR_*_syscall_max+1 because the array size is implied by the number of syscalls in the generated headers. Hence, there is no need to include <asm/unistd.h>, either. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210517073815.97426-4-masahiroy@kernel.org
2021-05-20x86/syscalls: Switch to generic syscalltbl.shMasahiro Yamada2-9/+8
Many architectures duplicate similar shell scripts. Convert x86 and UML to use scripts/syscalltbl.sh. The generic script generates seperate headers for x86/64 and x86/x32 syscalls, while the x86 specific script coalesced them into one. Adjust the code accordingly. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210517073815.97426-3-masahiroy@kernel.org
2021-04-15um: elf.h: Fix W=1 warning for empty body in 'do' statementRandy Dunlap1-1/+1
Use the common kernel style to eliminate a warning: ./arch/x86/um/asm/elf.h:215:32: warning: suggest braces around empty body in ‘do’ statement [-Wempty-body] #define SET_PERSONALITY(ex) do ; while(0) ^ Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: linux-um@lists.infradead.org Signed-off-by: Richard Weinberger <richard@nod.at>
2021-04-15um: Add 2 missing libs to fix various build errorsRandy Dunlap1-0/+1
Fix many build errors (at least 18 build error reports) for uml on i386 by adding 2 more library object files. All missing symbols are either cmpxchg8b_emu or atomic*386. Here are a few examples of the build errors that are eliminated: /usr/bin/ld: core.c:(.text+0xd83): undefined reference to `cmpxchg8b_emu' /usr/bin/ld: core.c:(.text+0x2bb2): undefined reference to `atomic64_add_386' /usr/bin/ld: core.c:(.text+0x2c5d): undefined reference to `atomic64_xchg_386' syscall.c:(.text+0x2f49): undefined reference to `atomic64_set_386' /usr/bin/ld: syscall.c:(.text+0x2f54): undefined reference to `atomic64_set_386' syscall.c:(.text+0x33a4): undefined reference to `atomic64_inc_386' /usr/bin/ld: syscall.c:(.text+0x33ac): undefined reference to `atomic64_inc_386' /usr/bin/ld: net/ipv4/inet_timewait_sock.o: in function `inet_twsk_alloc': inet_timewait_sock.c:(.text+0x3d1): undefined reference to `atomic64_read_386' /usr/bin/ld: inet_timewait_sock.c:(.text+0x3dd): undefined reference to `atomic64_set_386' /usr/bin/ld: net/ipv4/inet_connection_sock.o: in function `inet_csk_clone_lock': inet_connection_sock.c:(.text+0x1d74): undefined reference to `atomic64_read_386' /usr/bin/ld: inet_connection_sock.c:(.text+0x1d80): undefined reference to `atomic64_set_386' /usr/bin/ld: net/ipv4/tcp_input.o: in function `inet_reqsk_alloc': tcp_input.c:(.text+0xa345): undefined reference to `atomic64_set_386' /usr/bin/ld: net/mac80211/wpa.o: in function `ieee80211_crypto_tkip_encrypt': wpa.c:(.text+0x739): undefined reference to `atomic64_inc_return_386' Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: kernel test robot <lkp@intel.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: kbuild-all@lists.01.org Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: linux-um@lists.infradead.org Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-04-15um: Fix tag order in stub_32.hJohannes Berg1-1/+1
"static void inline" is the wrong way around, fix that. Reported-by: kernel test robot <lkp@intel.com> Fixes: 9f0b4807a44f ("um: rework userspace stubs to not hard-code stub location") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-02-12um: remove process stub VMAJohannes Berg1-1/+1
This mostly reverts the old commit 3963333fe676 ("uml: cover stubs with a VMA") which had added a VMA to the existing PTEs. However, there's no real reason to have the PTEs in the first place and the VMA cannot be 'fixed' in place, which leads to bugs that userspace could try to unmap them and be forcefully killed, or such. Also, there's a bit of an ugly hole in userspace's address space. Simplify all this: just install the stub code/page at the top of the (inner) address space, i.e. put it just above TASK_SIZE. The pages are simply hard-coded to be mapped in the userspace process we use to implement an mm context, and they're out of reach of the inner mmap/munmap/mprotect etc. since they're above TASK_SIZE. Getting rid of the VMA also makes vma_merge() no longer hit one of the VM_WARN_ON()s there because we installed a VMA while the code assumes the stack VMA is the first one. It also removes a lockdep warning about mmap_sem usage since we no longer have uml_setup_stubs() and thus no longer need to do any manipulation that would require mmap_sem in activate_mm(). Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-02-12um: rework userspace stubs to not hard-code stub locationJohannes Berg5-34/+62
The userspace stacks mostly have a stack (and in the case of the syscall stub we can just set their stack pointer) that points to the location of the stub data page already. Rework the stubs to use the stack pointer to derive the start of the data page, rather than requiring it to be hard-coded. In the clone stub, also integrate the int3 into the stack remap, since we really must not use the stack while we remap it. This prepares for putting the stub at a variable location that's not part of the normal address space of the userspace processes running inside the UML machine. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2021-02-12um: separate child and parent errors in clone stubJohannes Berg2-2/+2
If the two are mixed up, then it looks as though the parent returned an error if the child failed (before) the mmap(), and then the resulting process never gets killed. Fix this by splitting the child and parent errors, reporting and using them appropriately. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2020-10-26arch/um: partially revert the conversion to __section() macroLinus Torvalds1-1/+1
A couple of um files ended up not including the header file that defines the __section() macro, and the simplest fix is to just revert the change for those files. Fixes: 33def8498fdd treewide: Convert macro and uses of __section(foo) to __section("foo") Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net> Cc: Joe Perches <joe@perches.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-25treewide: Convert macro and uses of __section(foo) to __section("foo")Joe Perches1-1/+1
Use a more generic form for __section that requires quotes to avoid complications with clang and gcc differences. Remove the quote operator # from compiler_attributes.h __section macro. Convert all unquoted __section(foo) uses to quoted __section("foo"). Also convert __attribute__((section("foo"))) uses to __section("foo") even if the __attribute__ has multiple list entry forms. Conversion done using the script at: https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-18Merge tag 'for-linus-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/umlLinus Torvalds2-13/+2
Pull UML updates from Richard Weinberger: - Improve support for non-glibc systems - Vector: Add support for scripting and dynamic tap devices - Various fixes for the vector networking driver - Various fixes for time travel mode * tag 'for-linus-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: vector: Add dynamic tap interfaces and scripting um: Clean up stacktrace dump um: Fix incorrect assumptions about max pid length um: Remove dead usage of TIF_IA32 um: Remove redundant NULL check um: change sigio_spinlock to a mutex um: time-travel: Return the sequence number in ACK messages um: time-travel: Fix IRQ handling in time_travel_handle_message() um: Allow static linking for non-glibc implementations um: Some fixes to build UML with musl um: vector: Use GFP_ATOMIC under spin lock um: Fix null pointer dereference in vector_user_bpf
2020-10-11um: Remove dead usage of TIF_IA32Gabriel Krisman Bertazi1-12/+1
This seems like a dead artifact since TIF_IA32 is not even defined as a TI flag for UM. Looking back in git history, it made sense in the old days, but it is apparently not used since UM was split out of the x86 arch/. It is also going away from the x86 tree soon. Also, I think the variable clean up it performs is not needed as 64-bit UML doesn't run 32-bit binaries as far as I can tell, and 32-bit UML has 32-bit ulong. Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2020-10-11um: Some fixes to build UML with muslIgnat Korchagin1-1/+1
musl toolchain and headers are a bit more strict. These fixes enable building UML with musl as well as seem not to break on glibc. Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Tested-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2020-08-20saner calling conventions for csum_and_copy_..._user()Al Viro1-23/+0
All callers of these primitives will * discard anything we might've copied in case of error * ignore the csum value in case of error * always pass 0xffffffff as the initial sum, so the resulting csum value (in case of success, that is) will never be 0. That suggest the following calling conventions: * don't pass err_ptr - just return 0 on error. * don't bother with zeroing destination, etc. in case of error * don't pass the initial sum - just use 0xffffffff. This commit does the minimal conversion in the instances of csum_and_copy_...(); the changes of actual asm code behind them are done later in the series. Note that this asm code is often shared with csum_partial_copy_nocheck(); the difference is that csum_partial_copy_nocheck() passes 0 for initial sum while csum_and_copy_..._user() pass 0xffffffff. Fortunately, we are free to pass 0xffffffff in all cases and subsequent patches will use that freedom without any special comments. A part that could be split off: parisc and uml/i386 claimed to have csum_and_copy_to_user() instances of their own, but those were identical to the generic one, so we simply drop them. Not sure if it's worth a separate commit... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-20unify generic instances of csum_partial_copy_nocheck()Al Viro1-16/+0
quite a few architectures have the same csum_partial_copy_nocheck() - simply memcpy() the data and then return the csum of the copy. hexagon, parisc, ia64, s390, um: explicitly spelled out that way. arc, arm64, csky, h8300, m68k/nommu, microblaze, mips/GENERIC_CSUM, nds32, nios2, openrisc, riscv, unicore32: end up picking the same thing spelled out in lib/checksum.h (with varying amounts of perversions along the way). everybody else (alpha, arm, c6x, m68k/mmu, mips/!GENERIC_CSUM, powerpc, sh, sparc, x86, xtensa) have non-generic variants. For all except c6x the declaration is in their asm/checksum.h. c6x uses the wrapper from asm-generic/checksum.h that would normally lead to the lib/checksum.h instance, but in case of c6x we end up using an asm function from arch/c6x instead. Screw that mess - have architectures with private instances define _HAVE_ARCH_CSUM_AND_COPY in their asm/checksum.h and have the default one right in net/checksum.h conditional on _HAVE_ARCH_CSUM_AND_COPY *not* defined. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-07-07kbuild: remove cc-option test of -fno-stack-protectorMasahiro Yamada1-1/+1
Some Makefiles already pass -fno-stack-protector unconditionally. For example, arch/arm64/kernel/vdso/Makefile, arch/x86/xen/Makefile. No problem report so far about hard-coding this option. So, we can assume all supported compilers know -fno-stack-protector. GCC 4.8 and Clang support this option (https://godbolt.org/z/_HDGzN) Get rid of cc-option from -fno-stack-protector. Remove CONFIG_CC_HAS_STACKPROTECTOR_NONE, which is always 'y'. Note: arch/mips/vdso/Makefile adds -fno-stack-protector twice, first unconditionally, and second conditionally. I removed the second one. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2020-06-09mmap locking API: use coccinelle to convert mmap_sem rwsem call sitesMichel Lespinasse1-2/+2
This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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