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2022-04-20tlb: hugetlb: Add more sizes to tlb_remove_huge_tlb_entrySteve Capper1-3/+7
[ Upstream commit 697a1d44af8ba0477ee729e632f4ade37999249a ] tlb_remove_huge_tlb_entry only considers PMD_SIZE and PUD_SIZE when updating the mmu_gather structure. Unfortunately on arm64 there are two additional huge page sizes that need to be covered: CONT_PTE_SIZE and CONT_PMD_SIZE. Where an end-user attempts to employ contiguous huge pages, a VM_BUG_ON can be experienced due to the fact that the tlb structure hasn't been correctly updated by the relevant tlb_flush_p.._range() call from tlb_remove_huge_tlb_entry. This patch adds inequality logic to the generic implementation of tlb_remove_huge_tlb_entry s.t. CONT_PTE_SIZE and CONT_PMD_SIZE are effectively covered on arm64. Also, as well as ptes, pmds and puds; p4ds are now considered too. Reported-by: David Hildenbrand <david@redhat.com> Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/linux-mm/811c5c8e-b3a2-85d2-049c-717f17c3a03a@redhat.com/ Signed-off-by: Steve Capper <steve.capper@arm.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220330112543.863-1-steve.capper@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-18vmlinux.lds.h: Handle clang's module.{c,d}tor sectionsNathan Chancellor1-0/+1
commit 848378812e40152abe9b9baf58ce2004f76fb988 upstream. A recent change in LLVM causes module_{c,d}tor sections to appear when CONFIG_K{A,C}SAN are enabled, which results in orphan section warnings because these are not handled anywhere: ld.lld: warning: arch/x86/pci/built-in.a(legacy.o):(.text.asan.module_ctor) is being placed in '.text.asan.module_ctor' ld.lld: warning: arch/x86/pci/built-in.a(legacy.o):(.text.asan.module_dtor) is being placed in '.text.asan.module_dtor' ld.lld: warning: arch/x86/pci/built-in.a(legacy.o):(.text.tsan.module_ctor) is being placed in '.text.tsan.module_ctor' Fangrui explains: "the function asan.module_ctor has the SHF_GNU_RETAIN flag, so it is in a separate section even with -fno-function-sections (default)". Place them in the TEXT_TEXT section so that these technologies continue to work with the newer compiler versions. All of the KASAN and KCSAN KUnit tests continue to pass after this change. Cc: stable@vger.kernel.org Link: https://github.com/ClangBuiltLinux/linux/issues/1432 Link: https://github.com/llvm/llvm-project/commit/7b789562244ee941b7bf2cefeb3fc08a59a01865 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Fangrui Song <maskray@google.com> Acked-by: Marco Elver <elver@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210731023107.1932981-1-nathan@kernel.org [nc: Resolve conflict due to lack of cf68fffb66d60] Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-14sched/core: Initialize the idle task with preemption disabledValentin Schneider1-1/+1
[ Upstream commit f1a0a376ca0c4ef1fc3d24e3e502acbb5b795674 ] As pointed out by commit de9b8f5dcbd9 ("sched: Fix crash trying to dequeue/enqueue the idle thread") init_idle() can and will be invoked more than once on the same idle task. At boot time, it is invoked for the boot CPU thread by sched_init(). Then smp_init() creates the threads for all the secondary CPUs and invokes init_idle() on them. As the hotplug machinery brings the secondaries to life, it will issue calls to idle_thread_get(), which itself invokes init_idle() yet again. In this case it's invoked twice more per secondary: at _cpu_up(), and at bringup_cpu(). Given smp_init() already initializes the idle tasks for all *possible* CPUs, no further initialization should be required. Now, removing init_idle() from idle_thread_get() exposes some interesting expectations with regards to the idle task's preempt_count: the secondary startup always issues a preempt_disable(), requiring some reset of the preempt count to 0 between hot-unplug and hotplug, which is currently served by idle_thread_get() -> idle_init(). Given the idle task is supposed to have preemption disabled once and never see it re-enabled, it seems that what we actually want is to initialize its preempt_count to PREEMPT_DISABLED and leave it there. Do that, and remove init_idle() from idle_thread_get(). Secondary startups were patched via coccinelle: @begone@ @@ -preempt_disable(); ... cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20210512094636.2958515-1-valentin.schneider@arm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-16vmlinux.lds.h: Avoid orphan section with !SMPNathan Chancellor1-0/+1
commit d4c6399900364facd84c9e35ce1540b6046c345f upstream. With x86_64_defconfig and the following configs, there is an orphan section warning: CONFIG_SMP=n CONFIG_AMD_MEM_ENCRYPT=y CONFIG_HYPERVISOR_GUEST=y CONFIG_KVM=y CONFIG_PARAVIRT=y ld: warning: orphan section `.data..decrypted' from `arch/x86/kernel/cpu/vmware.o' being placed in section `.data..decrypted' ld: warning: orphan section `.data..decrypted' from `arch/x86/kernel/kvm.o' being placed in section `.data..decrypted' These sections are created with DEFINE_PER_CPU_DECRYPTED, which ultimately turns into __PCPU_ATTRS, which in turn has a section attribute with a value of PER_CPU_BASE_SECTION + the section name. When CONFIG_SMP is not set, the base section is .data and that is not currently handled in any linker script. Add .data..decrypted to PERCPU_DECRYPTED_SECTION, which is included in PERCPU_INPUT -> PERCPU_SECTION, which is include in the x86 linker script when either CONFIG_X86_64 or CONFIG_SMP is unset, taking care of the warning. Fixes: ac26963a1175 ("percpu: Introduce DEFINE_PER_CPU_DECRYPTED") Link: https://github.com/ClangBuiltLinux/linux/issues/1360 Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> # build Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210506001410.1026691-1-nathan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-30static_call: Allow module use without exposing static_call_keyJosh Poimboeuf1-1/+4
[ Upstream commit 73f44fe19d359635a607e8e8daa0da4001c1cfc2 ] When exporting static_call_key; with EXPORT_STATIC_CALL*(), the module can use static_call_update() to change the function called. This is not desirable in general. Not exporting static_call_key however also disallows usage of static_call(), since objtool needs the key to construct the static_call_site. Solve this by allowing objtool to create the static_call_site using the trampoline address when it builds a module and cannot find the static_call_key symbol. The module loader will then try and map the trampole back to a key before it constructs the normal sites list. Doing this requires a trampoline -> key associsation, so add another magic section that keeps those. Originally-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20210127231837.ifddpn7rhwdaepiu@treble Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04vmlinux.lds.h: Define SANTIZER_DISCARDS with CONFIG_GCOV_KERNEL=yNathan Chancellor1-4/+5
commit f5b6a74d9c08b19740ca056876bf6584acdba582 upstream. clang produces .eh_frame sections when CONFIG_GCOV_KERNEL is enabled, even when -fno-asynchronous-unwind-tables is in KBUILD_CFLAGS: $ make CC=clang vmlinux ... ld: warning: orphan section `.eh_frame' from `init/main.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/version.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/do_mounts.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/do_mounts_initrd.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/initramfs.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/calibrate.o' being placed in section `.eh_frame' ld: warning: orphan section `.eh_frame' from `init/init_task.o' being placed in section `.eh_frame' ... $ rg "GCOV_KERNEL|GCOV_PROFILE_ALL" .config CONFIG_GCOV_KERNEL=y CONFIG_ARCH_HAS_GCOV_PROFILE_ALL=y CONFIG_GCOV_PROFILE_ALL=y This was already handled for a couple of other options in commit d812db78288d ("vmlinux.lds.h: Avoid KASAN and KCSAN's unwanted sections") and there is an open LLVM bug for this issue. Take advantage of that section for this config as well so that there are no more orphan warnings. Link: https://bugs.llvm.org/show_bug.cgi?id=46478 Link: https://github.com/ClangBuiltLinux/linux/issues/1069 Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Fangrui Song <maskray@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Fixes: d812db78288d ("vmlinux.lds.h: Avoid KASAN and KCSAN's unwanted sections") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210130004650.2682422-1-nathan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04vmlinux.lds.h: add DWARF v5 sectionsNick Desaulniers1-1/+6
commit 3c4fa46b30c551b1df2fb1574a684f68bc22067c upstream. We expect toolchains to produce these new debug info sections as part of DWARF v5. Add explicit placements to prevent the linker warnings from --orphan-section=warn. Compilers may produce such sections with explicit -gdwarf-5, or based on the implicit default version of DWARF when -g is used via DEBUG_INFO. This implicit default changes over time, and has changed to DWARF v5 with GCC 11. .debug_sup was mentioned in review, but without compilers producing it today, let's wait to add it until it becomes necessary. Cc: stable@vger.kernel.org Link: https://bugzilla.redhat.com/show_bug.cgi?id=1922707 Reported-by: Chris Murphy <lists@colorremedies.com> Suggested-by: Fangrui Song <maskray@google.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Mark Wielaard <mark@klomp.org> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-17firmware_loader: align .builtin_fw to 8Fangrui Song1-1/+1
[ Upstream commit 793f49a87aae24e5bcf92ad98d764153fc936570 ] arm64 references the start address of .builtin_fw (__start_builtin_fw) with a pair of R_AARCH64_ADR_PREL_PG_HI21/R_AARCH64_LDST64_ABS_LO12_NC relocations. The compiler is allowed to emit the R_AARCH64_LDST64_ABS_LO12_NC relocation because struct builtin_fw in include/linux/firmware.h is 8-byte aligned. The R_AARCH64_LDST64_ABS_LO12_NC relocation requires the address to be a multiple of 8, which may not be the case if .builtin_fw is empty. Unconditionally align .builtin_fw to fix the linker error. 32-bit architectures could use ALIGN(4) but that would add unnecessary complexity, so just use ALIGN(8). Link: https://lkml.kernel.org/r/20201208054646.2913063-1-maskray@google.com Link: https://github.com/ClangBuiltLinux/linux/issues/1204 Fixes: 5658c76 ("firmware: allow firmware files to be built into kernel image") Signed-off-by: Fangrui Song <maskray@google.com> Reported-by: kernel test robot <lkp@intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Douglas Anderson <dianders@chromium.org> Acked-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-27arm64: make atomic helpers __always_inlineArnd Bergmann1-3/+3
[ Upstream commit c35a824c31834d947fb99b0c608c1b9f922b4ba0 ] With UBSAN enabled and building with clang, there are occasionally warnings like WARNING: modpost: vmlinux.o(.text+0xc533ec): Section mismatch in reference from the function arch_atomic64_or() to the variable .init.data:numa_nodes_parsed The function arch_atomic64_or() references the variable __initdata numa_nodes_parsed. This is often because arch_atomic64_or lacks a __initdata annotation or the annotation of numa_nodes_parsed is wrong. for functions that end up not being inlined as intended but operating on __initdata variables. Mark these as __always_inline, along with the corresponding asm-generic wrappers. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210108092024.4034860-1-arnd@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-12local64.h: make <asm/local64.h> mandatoryRandy Dunlap1-0/+1
[ Upstream commit 87dbc209ea04645fd2351981f09eff5d23f8e2e9 ] Make <asm-generic/local64.h> mandatory in include/asm-generic/Kbuild and remove all arch/*/include/asm/local64.h arch-specific files since they only #include <asm-generic/local64.h>. This fixes build errors on arch/c6x/ and arch/nios2/ for block/blk-iocost.c. Build-tested on 21 of 25 arch-es. (tools problems on the others) Yes, we could even rename <asm-generic/local64.h> to <linux/local64.h> and change all #includes to use <linux/local64.h> instead. Link: https://lkml.kernel.org/r/20201227024446.17018-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Suggested-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Masahiro Yamada <masahiroy@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-15Merge branch 'for-5.10-fixes' of ↵Linus Torvalds1-9/+9
git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu Pull percpu fix and cleanup from Dennis Zhou: "A fix for a Wshadow warning in the asm-generic percpu macros came in and then I tacked on the removal of flexible array initializers in the percpu allocator" * 'for-5.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu: percpu: convert flexible array initializers to use struct_size() asm-generic: percpu: avoid Wshadow warning
2020-11-14compiler.h: fix barrier_data() on clangArvind Sankar1-0/+1
Commit 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive") neglected to copy barrier_data() from compiler-gcc.h into compiler-clang.h. The definition in compiler-gcc.h was really to work around clang's more aggressive optimization, so this broke barrier_data() on clang, and consequently memzero_explicit() as well. For example, this results in at least the memzero_explicit() call in lib/crypto/sha256.c:sha256_transform() being optimized away by clang. Fix this by moving the definition of barrier_data() into compiler.h. Also move the gcc/clang definition of barrier() into compiler.h, __memory_barrier() is icc-specific (and barrier() is already defined using it in compiler-intel.h) and doesn't belong in compiler.h. [rdunlap@infradead.org: fix ALPHA builds when SMP is not enabled] Link: https://lkml.kernel.org/r/20201101231835.4589-1-rdunlap@infradead.org Fixes: 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive") Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20201014212631.207844-1-nivedita@alum.mit.edu Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-30Merge tag 'asm-generic-fixes-5.10' of ↵Linus Torvalds1-2/+4
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic fix from Arnd Bergmann: "One small bugfix, fixing a build regression for RISC-V" * tag 'asm-generic-fixes-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: mark __{get,put}_user_fn as __always_inline
2020-10-27vmlinux.lds.h: Keep .ctors.* with .ctorsKees Cook1-0/+1
Under some circumstances, the compiler generates .ctors.* sections. This is seen doing a cross compile of x86_64 from a powerpc64el host: x86_64-linux-gnu-ld: warning: orphan section `.ctors.65435' from `kernel/trace/trace_clock.o' being placed in section `.ctors.65435' x86_64-linux-gnu-ld: warning: orphan section `.ctors.65435' from `kernel/trace/ftrace.o' being placed in section `.ctors.65435' x86_64-linux-gnu-ld: warning: orphan section `.ctors.65435' from `kernel/trace/ring_buffer.o' being placed in section `.ctors.65435' Include these orphans along with the regular .ctors section. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Fixes: 83109d5d5fba ("x86/build: Warn on orphan section placement") Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/r/20201005025720.2599682-1-keescook@chromium.org
2020-10-27asm-generic: mark __{get,put}_user_fn as __always_inlineChristoph Hellwig1-2/+4
Without the explicit __always_inline, some RISC-V configs place the functions out of line, triggering the BUILD_BUG_ON checks in the function. Fixes: 11129e8ed4d9 ("riscv: use memcpy based uaccess for nommu again") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-10-26asm-generic: percpu: avoid Wshadow warningArnd Bergmann1-9/+9
Nesting macros that use the same local variable names causes warnings when building with "make W=2": include/asm-generic/percpu.h:117:14: warning: declaration of '__ret' shadows a previous local [-Wshadow] include/asm-generic/percpu.h:126:14: warning: declaration of '__ret' shadows a previous local [-Wshadow] These are fairly harmless, but since the warning comes from a global header, the warning happens every time the headers are included, which is fairly annoying. Rename the variables to avoid shadowing and shut up the warning. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Signed-off-by: Dennis Zhou <dennis@kernel.org>
2020-10-25treewide: Convert macro and uses of __section(foo) to __section("foo")Joe Perches3-6/+6
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>
2020-10-24Merge tag 'riscv-for-linus-5.10-mw1' of ↵Linus Torvalds1-40/+69
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: "Just a single patch set: the remainder of Christoph's work to remove set_fs, including the RISC-V portion" * tag 'riscv-for-linus-5.10-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: remove address space overrides using set_fs() riscv: implement __get_kernel_nofault and __put_user_nofault riscv: refactor __get_user and __put_user riscv: use memcpy based uaccess for nommu again asm-generic: make the set_fs implementation optional asm-generic: add nommu implementations of __{get,put}_kernel_nofault asm-generic: improve the nommu {get,put}_user handling uaccess: provide a generic TASK_SIZE_MAX definition
2020-10-22Merge tag 'kbuild-v5.10' of ↵Linus Torvalds2-0/+11
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Support 'make compile_commands.json' to generate the compilation database more easily, avoiding stale entries - Support 'make clang-analyzer' and 'make clang-tidy' for static checks using clang-tidy - Preprocess scripts/modules.lds.S to allow CONFIG options in the module linker script - Drop cc-option tests from compiler flags supported by our minimal GCC/Clang versions - Use always 12-digits commit hash for CONFIG_LOCALVERSION_AUTO=y - Use sha1 build id for both BFD linker and LLD - Improve deb-pkg for reproducible builds and rootless builds - Remove stale, useless scripts/namespace.pl - Turn -Wreturn-type warning into error - Fix build error of deb-pkg when CONFIG_MODULES=n - Replace 'hostname' command with more portable 'uname -n' - Various Makefile cleanups * tag 'kbuild-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits) kbuild: Use uname for LINUX_COMPILE_HOST detection kbuild: Only add -fno-var-tracking-assignments for old GCC versions kbuild: remove leftover comment for filechk utility treewide: remove DISABLE_LTO kbuild: deb-pkg: clean up package name variables kbuild: deb-pkg: do not build linux-headers package if CONFIG_MODULES=n kbuild: enforce -Werror=return-type scripts: remove namespace.pl builddeb: Add support for all required debian/rules targets builddeb: Enable rootless builds builddeb: Pass -n to gzip for reproducible packages kbuild: split the build log of kallsyms kbuild: explicitly specify the build id style scripts/setlocalversion: make git describe output more reliable kbuild: remove cc-option test of -Werror=date-time kbuild: remove cc-option test of -fno-stack-check kbuild: remove cc-option test of -fno-strict-overflow kbuild: move CFLAGS_{KASAN,UBSAN,KCSAN} exports to relevant Makefiles kbuild: remove redundant CONFIG_KASAN check from scripts/Makefile.kasan kbuild: do not create built-in objects for external module builds ...
2020-10-22Merge tag 'pci-v5.10-changes' of ↵Linus Torvalds1-12/+27
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: "Enumeration: - Print IRQ number used by PCIe Link Bandwidth Notification (Dongdong Liu) - Add schedule point in pci_read_config() to reduce max latency (Jiang Biao) - Add Kconfig options for MPS/MRRS strategy (Jim Quinlan) Resource management: - Fix pci_iounmap() memory leak when !CONFIG_GENERIC_IOMAP (Lorenzo Pieralisi) PCIe native device hotplug: - Reduce noisiness on hot removal (Lukas Wunner) Power management: - Revert "PCI/PM: Apply D2 delay as milliseconds, not microseconds" that was done on the basis of spec typo (Bjorn Helgaas) - Rename pci_dev.d3_delay to d3hot_delay to remove D3hot/D3cold ambiguity (Krzysztof Wilczyński) - Remove unused pcibios_pm_ops (Vaibhav Gupta) IOMMU: - Enable Translation Blocking for external devices to harden against DMA attacks (Rajat Jain) Error handling: - Add an ACPI APEI notifier chain for vendor CPER records to enable device-specific error handling (Shiju Jose) ASPM: - Remove struct aspm_register_info to simplify code (Saheed O. Bolarinwa) Amlogic Meson PCIe controller driver: - Build as module by default (Kevin Hilman) Ampere Altra PCIe controller driver: - Add MCFG quirk to work around non-standard ECAM implementation (Tuan Phan) Broadcom iProc PCIe controller driver: - Set affinity mask on MSI interrupts (Mark Tomlinson) Broadcom STB PCIe controller driver: - Make PCIE_BRCMSTB depend on ARCH_BRCMSTB (Jim Quinlan) - Add DT bindings for more Brcmstb chips (Jim Quinlan) - Add bcm7278 register info (Jim Quinlan) - Add bcm7278 PERST# support (Jim Quinlan) - Add suspend and resume pm_ops (Jim Quinlan) - Add control of rescal reset (Jim Quinlan) - Set additional internal memory DMA viewport sizes (Jim Quinlan) - Accommodate MSI for older chips (Jim Quinlan) - Set bus max burst size by chip type (Jim Quinlan) - Add support for bcm7211, bcm7216, bcm7445, bcm7278 (Jim Quinlan) Freescale i.MX6 PCIe controller driver: - Use dev_err_probe() to reduce redundant messages (Anson Huang) Freescale Layerscape PCIe controller driver: - Enforce 4K DMA buffer alignment in endpoint test (Hou Zhiqiang) - Add DT compatible strings for ls1088a, ls2088a (Xiaowei Bao) - Add endpoint support for ls1088a, ls2088a (Xiaowei Bao) - Add endpoint test support for lS1088a (Xiaowei Bao) - Add MSI-X support for ls1088a (Xiaowei Bao) HiSilicon HIP PCIe controller driver: - Handle HIP-specific errors via ACPI APEI (Yicong Yang) HiSilicon Kirin PCIe controller driver: - Return -EPROBE_DEFER if the GPIO isn't ready (Bean Huo) Intel VMD host bridge driver: - Factor out physical offset, bus offset, IRQ domain, IRQ allocation (Jon Derrick) - Use generic PCI PM correctly (Jon Derrick) Marvell Aardvark PCIe controller driver: - Fix compilation on s390 (Pali Rohár) - Implement driver 'remove' function and allow to build it as module (Pali Rohár) - Move PCIe reset card code to advk_pcie_train_link() (Pali Rohár) - Convert mvebu a3700 internal SMCC firmware return codes to errno (Pali Rohár) - Fix initialization with old Marvell's Arm Trusted Firmware (Pali Rohár) Microsoft Hyper-V host bridge driver: - Fix hibernation in case interrupts are not re-created (Dexuan Cui) NVIDIA Tegra PCIe controller driver: - Stop checking return value of debugfs_create() functions (Greg Kroah-Hartman) - Convert to use DEFINE_SEQ_ATTRIBUTE macro (Liu Shixin) Qualcomm PCIe controller driver: - Reset PCIe to work around Qsdk U-Boot issue (Ansuel Smith) Renesas R-Car PCIe controller driver: - Add DT documentation for r8a774a1, r8a774b1, r8a774e1 endpoints (Lad Prabhakar) - Add RZ/G2M, RZ/G2N, RZ/G2H IDs to endpoint test (Lad Prabhakar) - Add DT support for r8a7742 (Lad Prabhakar) Socionext UniPhier Pro5 controller driver: - Add DT descriptions of iATU register (host and endpoint) (Kunihiko Hayashi) Synopsys DesignWare PCIe controller driver: - Add link up check in dw_child_pcie_ops.map_bus() (racy, but seems unavoidable) (Hou Zhiqiang) - Fix endpoint Header Type check so multi-function devices work (Hou Zhiqiang) - Skip PCIE_MSI_INTR0* programming if MSI is disabled (Jisheng Zhang) - Stop leaking MSI page in suspend/resume (Jisheng Zhang) - Add common iATU register support instead of keystone-specific code (Kunihiko Hayashi) - Major config space access and other cleanups in dwc core and drivers that use it (al, exynos, histb, imx6, intel-gw, keystone, kirin, meson, qcom, tegra) (Rob Herring) - Add multiple PFs support for endpoint (Xiaowei Bao) - Add MSI-X doorbell mode in endpoint mode (Xiaowei Bao) Miscellaneous: - Use fallthrough pseudo-keyword (Gustavo A. R. Silva) - Fix "0 used as NULL pointer" warnings (Gustavo Pimentel) - Fix "cast truncates bits from constant value" warnings (Gustavo Pimentel) - Remove redundant zeroing for sg_init_table() (Julia Lawall) - Use scnprintf(), not snprintf(), in sysfs "show" functions (Krzysztof Wilczyński) - Remove unused assignments (Krzysztof Wilczyński) - Fix "0 used as NULL pointer" warning (Krzysztof Wilczyński) - Simplify bool comparisons (Krzysztof Wilczyński) - Use for_each_child_of_node() and for_each_node_by_name() (Qinglang Miao) - Simplify return expressions (Qinglang Miao)" * tag 'pci-v5.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (147 commits) PCI: vmd: Update VMD PM to correctly use generic PCI PM PCI: vmd: Create IRQ allocation helper PCI: vmd: Create IRQ Domain configuration helper PCI: vmd: Create bus offset configuration helper PCI: vmd: Create physical offset helper PCI: v3-semi: Remove unneeded break PCI: dwc: Add link up check in dw_child_pcie_ops.map_bus() PCI/ASPM: Remove struct pcie_link_state.l1ss PCI/ASPM: Remove struct aspm_register_info.l1ss_cap PCI/ASPM: Pass L1SS Capabilities value, not struct aspm_register_info PCI/ASPM: Remove struct aspm_register_info.l1ss_ctl1 PCI/ASPM: Remove struct aspm_register_info.l1ss_ctl2 (unused) PCI/ASPM: Remove struct aspm_register_info.l1ss_cap_ptr PCI/ASPM: Remove struct aspm_register_info.latency_encoding PCI/ASPM: Remove struct aspm_register_info.enabled PCI/ASPM: Remove struct aspm_register_info.support PCI/ASPM: Use 'parent' and 'child' for readability PCI/ASPM: Move LTR path check to where it's used PCI/ASPM: Move pci_clear_and_set_dword() earlier PCI: dwc: Fix MSI page leakage in suspend/resume ...
2020-10-18Merge tag 'linux-kselftest-kunit-5.10-rc1' of ↵Linus Torvalds1-1/+9
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull more Kunit updates from Shuah Khan: - add Kunit to kernel_init() and remove KUnit from init calls entirely. This addresses the concern that Kunit would not work correctly during late init phase. - add a linker section where KUnit can put references to its test suites. This is the first step in transitioning to dispatching all KUnit tests from a centralized executor rather than having each as its own separate late_initcall. - add a centralized executor to dispatch tests rather than relying on late_initcall to schedule each test suite separately. Centralized execution is for built-in tests only; modules will execute tests when loaded. - convert bitfield test to use KUnit framework - Documentation updates for naming guidelines and how kunit_test_suite() works. - add test plan to KUnit TAP format * tag 'linux-kselftest-kunit-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: lib: kunit: Fix compilation test when using TEST_BIT_FIELD_COMPILE lib: kunit: add bitfield test conversion to KUnit Documentation: kunit: add a brief blurb about kunit_test_suite kunit: test: add test plan to KUnit TAP format init: main: add KUnit to kernel init kunit: test: create a single centralized executor for all tests vmlinux.lds.h: add linker section for KUnit test suites Documentation: kunit: Add naming guidelines
2020-10-15Merge tag 'hyperv-next-signed' of ↵Linus Torvalds1-1/+3
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull another Hyper-V update from Wei Liu: "One patch from Michael to get VMbus interrupt from ACPI DSDT" * tag 'hyperv-next-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: Drivers: hv: vmbus: Add parsing of VMbus interrupt in ACPI DSDT
2020-10-15Merge tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds2-11/+0
Pull dma-mapping updates from Christoph Hellwig: - rework the non-coherent DMA allocator - move private definitions out of <linux/dma-mapping.h> - lower CMA_ALIGNMENT (Paul Cercueil) - remove the omap1 dma address translation in favor of the common code - make dma-direct aware of multiple dma offset ranges (Jim Quinlan) - support per-node DMA CMA areas (Barry Song) - increase the default seg boundary limit (Nicolin Chen) - misc fixes (Robin Murphy, Thomas Tai, Xu Wang) - various cleanups * tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping: (63 commits) ARM/ixp4xx: add a missing include of dma-map-ops.h dma-direct: simplify the DMA_ATTR_NO_KERNEL_MAPPING handling dma-direct: factor out a dma_direct_alloc_from_pool helper dma-direct check for highmem pages in dma_direct_alloc_pages dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h> dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma dma-mapping: move dma-debug.h to kernel/dma/ dma-mapping: remove <asm/dma-contiguous.h> dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h> dma-contiguous: remove dma_contiguous_set_default dma-contiguous: remove dev_set_cma_area dma-contiguous: remove dma_declare_contiguous dma-mapping: split <linux/dma-mapping.h> cma: decrease CMA_ALIGNMENT lower limit to 2 firewire-ohci: use dma_alloc_pages dma-iommu: implement ->alloc_noncoherent dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods dma-mapping: add a new dma_alloc_pages API dma-mapping: remove dma_cache_sync 53c700: convert to dma_alloc_noncoherent ...
2020-10-14Drivers: hv: vmbus: Add parsing of VMbus interrupt in ACPI DSDTMichael Kelley1-1/+3
On ARM64, Hyper-V now specifies the interrupt to be used by VMbus in the ACPI DSDT. This information is not used on x86 because the interrupt vector must be hardcoded. But update the generic VMbus driver to do the parsing and pass the information to the architecture specific code that sets up the Linux IRQ. Update consumers of the interrupt to get it from an architecture specific function. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/1597434304-40631-1-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2020-10-12Merge branch 'work.quota-compat' of ↵Linus Torvalds1-0/+8
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull compat quotactl cleanups from Al Viro: "More Christoph's compat cleanups: quotactl(2)" * 'work.quota-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: quota: simplify the quotactl compat handling compat: add a compat_need_64bit_alignment_fixup() helper compat: lift compat_s64 and compat_u64 to <asm-generic/compat.h>
2020-10-12Merge branch 'work.csum_and_copy' of ↵Linus Torvalds1-12/+0
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull copy_and_csum cleanups from Al Viro: "Saner calling conventions for csum_and_copy_..._user() and friends" [ Removing 800+ lines of code and cleaning stuff up is good - Linus ] * 'work.csum_and_copy' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: ppc: propagate the calling conventions change down to csum_partial_copy_generic() amd64: switch csum_partial_copy_generic() to new calling conventions sparc64: propagate the calling convention changes down to __csum_partial_copy_...() xtensa: propagate the calling conventions change down into csum_partial_copy_generic() mips: propagate the calling convention change down into __csum_partial_copy_..._user() mips: __csum_partial_copy_kernel() has no users left mips: csum_and_copy_{to,from}_user() are never called under KERNEL_DS sparc32: propagate the calling conventions change down to __csum_partial_copy_sparc_generic() i386: propagate the calling conventions change down to csum_partial_copy_generic() sh: propage the calling conventions change down to csum_partial_copy_generic() m68k: get rid of zeroing destination on error in csum_and_copy_from_user() arm: propagate the calling convention changes down to csum_partial_copy_from_user() alpha: propagate the calling convention changes down to csum_partial_copy.c helpers saner calling conventions for csum_and_copy_..._user() csum_and_copy_..._user(): pass 0xffffffff instead of 0 as initial sum csum_partial_copy_nocheck(): drop the last argument unify generic instances of csum_partial_copy_nocheck() icmp_push_reply(): reorder adding the checksum up skb_copy_and_csum_bits(): don't bother with the last argument
2020-10-12Merge tag 'core-static_call-2020-10-12' of ↵Linus Torvalds1-0/+13
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull static call support from Ingo Molnar: "This introduces static_call(), which is the idea of static_branch() applied to indirect function calls. Remove a data load (indirection) by modifying the text. They give the flexibility of function pointers, but with better performance. (This is especially important for cases where retpolines would otherwise be used, as retpolines can be pretty slow.) API overview: DECLARE_STATIC_CALL(name, func); DEFINE_STATIC_CALL(name, func); DEFINE_STATIC_CALL_NULL(name, typename); static_call(name)(args...); static_call_cond(name)(args...); static_call_update(name, func); x86 is supported via text patching, otherwise basic indirect calls are used, with function pointers. There's a second variant using inline code patching, inspired by jump-labels, implemented on x86 as well. The new APIs are utilized in the x86 perf code, a heavy user of function pointers, where static calls speed up the PMU handler by 4.2% (!). The generic implementation is not really excercised on other architectures, outside of the trivial test_static_call_init() self-test" * tag 'core-static_call-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) static_call: Fix return type of static_call_init tracepoint: Fix out of sync data passing by static caller tracepoint: Fix overly long tracepoint names x86/perf, static_call: Optimize x86_pmu methods tracepoint: Optimize using static_call() static_call: Allow early init static_call: Add some validation static_call: Handle tail-calls static_call: Add static_call_cond() x86/alternatives: Teach text_poke_bp() to emulate RET static_call: Add simple self-test for static calls x86/static_call: Add inline static call implementation for x86-64 x86/static_call: Add out-of-line static call implementation static_call: Avoid kprobes on inline static_call()s static_call: Add inline static call infrastructure static_call: Add basic static call infrastructure compiler.h: Make __ADDRESSABLE() symbol truly unique jump_label,module: Fix module lifetime for __jump_label_mod_text_reserved() module: Properly propagate MODULE_STATE_COMING failure module: Fix up module_notifier return values ...
2020-10-12Merge tag 'core-build-2020-10-12' of ↵Linus Torvalds1-7/+42
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull orphan section checking from Ingo Molnar: "Orphan link sections were a long-standing source of obscure bugs, because the heuristics that various linkers & compilers use to handle them (include these bits into the output image vs discarding them silently) are both highly idiosyncratic and also version dependent. Instead of this historically problematic mess, this tree by Kees Cook (et al) adds build time asserts and build time warnings if there's any orphan section in the kernel or if a section is not sized as expected. And because we relied on so many silent assumptions in this area, fix a metric ton of dependencies and some outright bugs related to this, before we can finally enable the checks on the x86, ARM and ARM64 platforms" * tag 'core-build-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) x86/boot/compressed: Warn on orphan section placement x86/build: Warn on orphan section placement arm/boot: Warn on orphan section placement arm/build: Warn on orphan section placement arm64/build: Warn on orphan section placement x86/boot/compressed: Add missing debugging sections to output x86/boot/compressed: Remove, discard, or assert for unwanted sections x86/boot/compressed: Reorganize zero-size section asserts x86/build: Add asserts for unwanted sections x86/build: Enforce an empty .got.plt section x86/asm: Avoid generating unused kprobe sections arm/boot: Handle all sections explicitly arm/build: Assert for unwanted sections arm/build: Add missing sections arm/build: Explicitly keep .ARM.attributes sections arm/build: Refactor linker script headers arm64/build: Assert for unwanted sections arm64/build: Add missing DWARF sections arm64/build: Use common DISCARDS in linker script arm64/build: Remove .eh_frame* sections due to unwind tables ...
2020-10-09vmlinux.lds.h: add linker section for KUnit test suitesBrendan Higgins1-1/+9
Add a linker section where KUnit can put references to its test suites. This patch is the first step in transitioning to dispatching all KUnit tests from a centralized executor rather than having each as its own separate late_initcall. Co-developed-by: Iurii Zaikin <yzaikin@google.com> Signed-off-by: Iurii Zaikin <yzaikin@google.com> Signed-off-by: Brendan Higgins <brendanhiggins@google.com> Reviewed-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-10-09Merge branch 'kcsan' of ↵Ingo Molnar4-172/+196
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/core Pull KCSAN updates for v5.10 from Paul E. McKenney: - Improve kernel messages. - Be more permissive with bitops races under KCSAN_ASSUME_PLAIN_WRITES_ATOMIC=y. - Optimize debugfs stat counters. - Introduce the instrument_*read_write() annotations, to provide a finer description of certain ops - using KCSAN's compound instrumentation. Use them for atomic RNW and bitops, where appropriate. Doing this might find new races. (Depends on the compiler having tsan-compound-read-before-write=1 support.) - Support atomic built-ins, which will help certain architectures, such as s390. - Misc enhancements and smaller fixes. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-10-06dma-mapping: remove <asm/dma-contiguous.h>Christoph Hellwig2-11/+0
Just provide a weak default definition of dma_contiguous_early_fixup and let arm override it. Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-05asm-generic/io.h: Fix !CONFIG_GENERIC_IOMAP pci_iounmap() implementationLorenzo Pieralisi1-12/+27
For arches that do not select CONFIG_GENERIC_IOMAP, the current pci_iounmap() function does nothing causing obvious memory leaks for mapped regions that are backed by MMIO physical space. In order to detect if a mapped pointer is IO vs MMIO, a check must made available to the pci_iounmap() function so that it can actually detect whether the pointer has to be unmapped. In configurations where CONFIG_HAS_IOPORT_MAP && !CONFIG_GENERIC_IOMAP, a mapped port is detected using an ioport_map() stub defined in asm-generic/io.h. Use the same logic to implement a stub (ie __pci_ioport_unmap()) that detects if the passed in pointer in pci_iounmap() is IO vs MMIO to iounmap conditionally and call it in pci_iounmap() fixing the issue. Leave __pci_ioport_unmap() as a NOP for all other config options. Tested-by: George Cherian <george.cherian@marvell.com> Link: https://lore.kernel.org/lkml/20200905024811.74701-1-yangyingliang@huawei.com Link: https://lore.kernel.org/lkml/20200824132046.3114383-1-george.cherian@marvell.com Link: https://lore.kernel.org/r/a9daf8d8444d0ebd00bc6d64e336ec49dbb50784.1600254147.git.lorenzo.pieralisi@arm.com Reported-by: George Cherian <george.cherian@marvell.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: George Cherian <george.cherian@marvell.com> Cc: Will Deacon <will@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Yang Yingliang <yangyingliang@huawei.com>
2020-10-04asm-generic: make the set_fs implementation optionalChristoph Hellwig1-0/+2
Put all the set_fs related code under CONFIG_SET_FS so that asm-generic/uaccess.h can be used for set_fs-less builds. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-10-04asm-generic: add nommu implementations of __{get,put}_kernel_nofaultChristoph Hellwig1-0/+16
Add native implementations of __{get,put}_kernel_nofault using {get,put}_unaligned, just like the {get,put}_user implementations. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-10-04asm-generic: improve the nommu {get,put}_user handlingChristoph Hellwig1-40/+51
Instead of reusing raw_{copy,to}_from_user implement separate handlers using {get,put}_unaligned. This ensures unaligned access is handled correctly, and avoid the need for the small constant size optimization in raw_{copy,to}_from_user. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-09-25kbuild: preprocess module linker scriptMasahiro Yamada2-0/+11
There was a request to preprocess the module linker script like we do for the vmlinux one. (https://lkml.org/lkml/2020/8/21/512) The difference between vmlinux.lds and module.lds is that the latter is needed for external module builds, thus must be cleaned up by 'make mrproper' instead of 'make clean'. Also, it must be created by 'make modules_prepare'. You cannot put it in arch/$(SRCARCH)/kernel/, which is cleaned up by 'make clean'. I moved arch/$(SRCARCH)/kernel/module.lds to ar