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* x86/stackprotector: Work around strict Clang TLS symbol requirementsArd Biesheuvel2024-11-081-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GCC and Clang both implement stack protector support based on Thread Local Storage (TLS) variables, and this is used in the kernel to implement per-task stack cookies, by copying a task's stack cookie into a per-CPU variable every time it is scheduled in. Both now also implement -mstack-protector-guard-symbol=, which permits the TLS variable to be specified directly. This is useful because it will allow to move away from using a fixed offset of 40 bytes into the per-CPU area on x86_64, which requires a lot of special handling in the per-CPU code and the runtime relocation code. However, while GCC is rather lax in its implementation of this command line option, Clang actually requires that the provided symbol name refers to a TLS variable (i.e., one declared with __thread), although it also permits the variable to be undeclared entirely, in which case it will use an implicit declaration of the right type. The upshot of this is that Clang will emit the correct references to the stack cookie variable in most cases, e.g., 10d: 64 a1 00 00 00 00 mov %fs:0x0,%eax 10f: R_386_32 __stack_chk_guard However, if a non-TLS definition of the symbol in question is visible in the same compilation unit (which amounts to the whole of vmlinux if LTO is enabled), it will drop the per-CPU prefix and emit a load from a bogus address. Work around this by using a symbol name that never occurs in C code, and emit it as an alias in the linker script. Fixes: 3fb0fdb3bbe7 ("x86/stackprotector/32: Make the canary into a regular percpu variable") Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Cc: stable@vger.kernel.org Link: https://github.com/ClangBuiltLinux/linux/issues/1854 Link: https://lore.kernel.org/r/20241105155801.1779119-2-brgerst@gmail.com
* rust: cfi: add support for CFI_CLANG with RustMatthew Maurer2024-09-161-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make it possible to use the Control Flow Integrity (CFI) sanitizer when Rust is enabled. Enabling CFI with Rust requires that CFI is configured to normalize integer types so that all integer types of the same size and signedness are compatible under CFI. Rust and C use the same LLVM backend for code generation, so Rust KCFI is compatible with the KCFI used in the kernel for C. In the case of FineIBT, CFI also depends on -Zpatchable-function-entry for rewriting the function prologue, so we set that flag for Rust as well. The flag for FineIBT requires rustc 1.80.0 or later, so include a Kconfig requirement for that. Enabling Rust will select CFI_ICALL_NORMALIZE_INTEGERS because the flag is required to use Rust with CFI. Using select rather than `depends on` avoids the case where Rust is not visible in menuconfig due to CFI_ICALL_NORMALIZE_INTEGERS not being enabled. One disadvantage of select is that RUST must `depends on` all of the things that CFI_ICALL_NORMALIZE_INTEGERS depends on to avoid invalid configurations. Alice has been using KCFI on her phone for several months, so it is reasonably well tested on arm64. Signed-off-by: Matthew Maurer <mmaurer@google.com> Co-developed-by: Alice Ryhl <aliceryhl@google.com> Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Tested-by: Gatlin Newhouse <gatlin.newhouse@gmail.com> Acked-by: Kees Cook <kees@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20240801-kcfi-v2-2-c93caed3d121@google.com [ Replaced `!FINEIBT` requirement with `!CALL_PADDING` to prevent a build error on older Rust compilers. Fixed typo. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
* x86/rust: support MITIGATION_RETHUNKMiguel Ojeda2024-08-181-0/+5
| | | | | | | | | | | | | | | | | | | | | | The Rust compiler added support for `-Zfunction-return=thunk-extern` [1] in 1.76.0 [2], i.e. the equivalent of `-mfunction-return=thunk-extern`. Thus add support for `MITIGATION_RETHUNK`. Without this, `objtool` would warn if enabled for Rust and already warns under IBT builds, e.g.: samples/rust/rust_print.o: warning: objtool: _R...init+0xa5c: 'naked' return found in RETHUNK build Link: https://github.com/rust-lang/rust/issues/116853 [1] Link: https://github.com/rust-lang/rust/pull/116892 [2] Reviewed-by: Gary Guo <gary@garyguo.net> Tested-by: Alice Ryhl <aliceryhl@google.com> Tested-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://github.com/Rust-for-Linux/linux/issues/945 Link: https://lore.kernel.org/r/20240725183325.122827-4-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
* x86/rust: support MITIGATION_RETPOLINEMiguel Ojeda2024-08-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support `MITIGATION_RETPOLINE` by enabling the target features that Clang does. The existing target feature being enabled was a leftover from our old `rust` branch, and it is not enough: the target feature `retpoline-external-thunk` only implies `retpoline-indirect-calls`, but not `retpoline-indirect-branches` (see LLVM's `X86.td`), unlike Clang's flag of the same name `-mretpoline-external-thunk` which does imply both (see Clang's `lib/Driver/ToolChains/Arch/X86.cpp`). Without this, `objtool` would complain if enabled for Rust, e.g.: rust/core.o: warning: objtool: _R...escape_default+0x13: indirect jump found in RETPOLINE build In addition, change the comment to note that LLVM is the one disabling jump tables when retpoline is enabled, thus we do not need to use `-Zno-jump-tables` for Rust here -- see commit c58f2166ab39 ("Introduce the "retpoline" x86 mitigation technique ...") [1]: The goal is simple: avoid generating code which contains an indirect branch that could have its prediction poisoned by an attacker. In many cases, the compiler can simply use directed conditional branches and a small search tree. LLVM already has support for lowering switches in this way and the first step of this patch is to disable jump-table lowering of switches and introduce a pass to rewrite explicit indirectbr sequences into a switch over integers. As well as a live example at [2]. These should be eventually enabled via `-Ctarget-feature` when `rustc` starts recognizing them (or via a new dedicated flag) [3]. Cc: Daniel Borkmann <daniel@iogearbox.net> Link: https://github.com/llvm/llvm-project/commit/c58f2166ab3987f37cb0d7815b561bff5a20a69a [1] Link: https://godbolt.org/z/G4YPr58qG [2] Link: https://github.com/rust-lang/rust/issues/116852 [3] Reviewed-by: Gary Guo <gary@garyguo.net> Tested-by: Alice Ryhl <aliceryhl@google.com> Tested-by: Benno Lossin <benno.lossin@proton.me> Link: https://github.com/Rust-for-Linux/linux/issues/945 Link: https://lore.kernel.org/r/20240725183325.122827-3-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
* Merge tag 'mm-nonmm-stable-2024-05-22-17-30' of ↵Linus Torvalds2024-05-231-0/+20
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more non-mm updates from Andrew Morton: - A series ("kbuild: enable more warnings by default") from Arnd Bergmann which enables a number of additional build-time warnings. We fixed all the fallout which we could find, there may still be a few stragglers. - Samuel Holland has developed the series "Unified cross-architecture kernel-mode FPU API". This does a lot of consolidation of per-architecture kernel-mode FPU usage and enables the use of newer AMD GPUs on RISC-V. - Tao Su has fixed some selftests build warnings in the series "Selftests: Fix compilation warnings due to missing _GNU_SOURCE definition". - This pull also includes a nilfs2 fixup from Ryusuke Konishi. * tag 'mm-nonmm-stable-2024-05-22-17-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (23 commits) nilfs2: make block erasure safe in nilfs_finish_roll_forward() selftests/harness: use 1024 in place of LINE_MAX Revert "selftests/harness: remove use of LINE_MAX" selftests/fpu: allow building on other architectures selftests/fpu: move FP code to a separate translation unit drm/amd/display: use ARCH_HAS_KERNEL_FPU_SUPPORT drm/amd/display: only use hard-float, not altivec on powerpc riscv: add support for kernel-mode FPU x86: implement ARCH_HAS_KERNEL_FPU_SUPPORT powerpc: implement ARCH_HAS_KERNEL_FPU_SUPPORT LoongArch: implement ARCH_HAS_KERNEL_FPU_SUPPORT lib/raid6: use CC_FLAGS_FPU for NEON CFLAGS arm64: crypto: use CC_FLAGS_FPU for NEON CFLAGS arm64: implement ARCH_HAS_KERNEL_FPU_SUPPORT ARM: crypto: use CC_FLAGS_FPU for NEON CFLAGS ARM: implement ARCH_HAS_KERNEL_FPU_SUPPORT arch: add ARCH_HAS_KERNEL_FPU_SUPPORT x86/fpu: fix asm/fpu/types.h include guard kbuild: enable -Wcast-function-type-strict unconditionally kbuild: enable -Wformat-truncation on clang ...
| * x86: implement ARCH_HAS_KERNEL_FPU_SUPPORTSamuel Holland2024-05-191-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | x86 already provides kernel_fpu_begin() and kernel_fpu_end(), but in a different header. Add a wrapper header, and export the CFLAGS adjustments as found in lib/Makefile. Link: https://lkml.kernel.org/r/20240329072441.591471-11-samuel.holland@sifive.com Signed-off-by: Samuel Holland <samuel.holland@sifive.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Christian König <christian.koenig@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nicolas Schier <nicolas@fjasle.eu> Cc: Palmer Dabbelt <palmer@rivosinc.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: WANG Xuerui <git@xen0n.name> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | arch: Select fbdev helpers with CONFIG_VIDEOThomas Zimmermann2024-05-031-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | Various Kconfig options selected the per-architecture helpers for fbdev. But none of the contained code depends on fbdev. Standardize on CONFIG_VIDEO, which will allow to add more general helpers for video functionality. CONFIG_VIDEO protects each architecture's video/ directory. This allows for the use of more fine-grained control for each directory's files, such as the use of CONFIG_STI_CORE on parisc. v2: - sparc: rebased onto Makefile changes Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: x86@kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* x86/build: Use obj-y to descend into arch/x86/virt/Masahiro Yamada2024-03-301-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | Commit c33621b4c5ad ("x86/virt/tdx: Wire up basic SEAMCALL functions") introduced a new instance of core-y instead of the standardized obj-y syntax. X86 Makefiles descend into subdirectories of arch/x86/virt inconsistently; into arch/x86/virt/ via core-y defined in arch/x86/Makefile, but into arch/x86/virt/svm/ via obj-y defined in arch/x86/Kbuild. This is problematic when you build a single object in parallel because multiple threads attempt to build the same file. $ make -j$(nproc) arch/x86/virt/vmx/tdx/seamcall.o [ snip ] AS arch/x86/virt/vmx/tdx/seamcall.o AS arch/x86/virt/vmx/tdx/seamcall.o fixdep: error opening file: arch/x86/virt/vmx/tdx/.seamcall.o.d: No such file or directory make[4]: *** [scripts/Makefile.build:362: arch/x86/virt/vmx/tdx/seamcall.o] Error 2 Use the obj-y syntax, as it works correctly. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20240330060554.18524-1-masahiroy@kernel.org
* Merge tag 'mm-nonmm-stable-2024-03-14-09-36' of ↵Linus Torvalds2024-03-151-6/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min heap optimizations". - Kuan-Wei Chiu has also sped up the library sorting code in the series "lib/sort: Optimize the number of swaps and comparisons". - Alexey Gladkov has added the ability for code running within an IPC namespace to alter its IPC and MQ limits. The series is "Allow to change ipc/mq sysctls inside ipc namespace". - Geert Uytterhoeven has contributed some dhrystone maintenance work in the series "lib: dhry: miscellaneous cleanups". - Ryusuke Konishi continues nilfs2 maintenance work in the series "nilfs2: eliminate kmap and kmap_atomic calls" "nilfs2: fix kernel bug at submit_bh_wbc()" - Nathan Chancellor has updated our build tools requirements in the series "Bump the minimum supported version of LLVM to 13.0.1". - Muhammad Usama Anjum continues with the selftests maintenance work in the series "selftests/mm: Improve run_vmtests.sh". - Oleg Nesterov has done some maintenance work against the signal code in the series "get_signal: minor cleanups and fix". Plus the usual shower of singleton patches in various parts of the tree. Please see the individual changelogs for details. * tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits) nilfs2: prevent kernel bug at submit_bh_wbc() nilfs2: fix failure to detect DAT corruption in btree and direct mappings ocfs2: enable ocfs2_listxattr for special files ocfs2: remove SLAB_MEM_SPREAD flag usage assoc_array: fix the return value in assoc_array_insert_mid_shortcut() buildid: use kmap_local_page() watchdog/core: remove sysctl handlers from public header nilfs2: use div64_ul() instead of do_div() mul_u64_u64_div_u64: increase precision by conditionally swapping a and b kexec: copy only happens before uchunk goes to zero get_signal: don't initialize ksig->info if SIGNAL_GROUP_EXIT/group_exec_task get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig get_signal: don't abuse ksig->info.si_signo and ksig->sig const_structs.checkpatch: add device_type Normalise "name (ad@dr)" MODULE_AUTHORs to "name <ad@dr>" dyndbg: replace kstrdup() + strchr() with kstrdup_and_replace() list: leverage list_is_head() for list_entry_is_head() nilfs2: MAINTAINERS: drop unreachable project mirror site smp: make __smp_processor_id() 0-argument macro fat: fix uninitialized field in nostale filehandles ...
| * x86: drop stack-alignment plugin optNathan Chancellor2024-02-231-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that the minimum supported version of LLVM for building the kernel has been bumped to 13.0.1, the inner ifeq statement is always false, as the build will fail during the configuration stage for older LLVM versions. This effectively reverts part of commit b33fff07e3e3 ("x86, build: allow LTO to be selected") and its follow up fix, commit 2398ce80152a ("x86, lto: Pass -stack-alignment only on LLD < 13.0.0"). Link: https://lkml.kernel.org/r/20240125-bump-min-llvm-ver-to-13-0-1-v1-3-f5ff9bda41c5@kernel.org Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Conor Dooley <conor@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Nicolas Schier <nicolas@fjasle.eu> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | Merge tag 'arm64-upstream' of ↵Linus Torvalds2024-03-141-0/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "The major features are support for LPA2 (52-bit VA/PA with 4K and 16K pages), the dpISA extension and Rust enabled on arm64. The changes are mostly contained within the usual arch/arm64/, drivers/perf, the arm64 Documentation and kselftests. The exception is the Rust support which touches some generic build files. Summary: - Reorganise the arm64 kernel VA space and add support for LPA2 (at stage 1, KVM stage 2 was merged earlier) - 52-bit VA/PA address range with 4KB and 16KB pages - Enable Rust on arm64 - Support for the 2023 dpISA extensions (data processing ISA), host only - arm64 perf updates: - StarFive's StarLink (integrates one or more CPU cores with a shared L3 memory system) PMU support - Enable HiSilicon Erratum 162700402 quirk for HIP09 - Several updates for the HiSilicon PCIe PMU driver - Arm CoreSight PMU support - Convert all drivers under drivers/perf/ to use .remove_new() - Miscellaneous: - Don't enable workarounds for "rare" errata by default - Clean up the DAIF flags handling for EL0 returns (in preparation for NMI support) - Kselftest update for ptrace() - Update some of the sysreg field definitions - Slight improvement in the code generation for inline asm I/O accessors to permit offset addressing - kretprobes: acquire regs via a BRK exception (previously done via a trampoline handler) - SVE/SME cleanups, comment updates - Allow CALL_OPS+CC_OPTIMIZE_FOR_SIZE with clang (previously disabled due to gcc silently ignoring -falign-functions=N)" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (134 commits) Revert "mm: add arch hook to validate mmap() prot flags" Revert "arm64: mm: add support for WXN memory translation attribute" Revert "ARM64: Dynamically allocate cpumasks and increase supported CPUs to 512" ARM64: Dynamically allocate cpumasks and increase supported CPUs to 512 kselftest/arm64: Add 2023 DPISA hwcap test coverage kselftest/arm64: Add basic FPMR test kselftest/arm64: Handle FPMR context in generic signal frame parser arm64/hwcap: Define hwcaps for 2023 DPISA features arm64/ptrace: Expose FPMR via ptrace arm64/signal: Add FPMR signal handling arm64/fpsimd: Support FEAT_FPMR arm64/fpsimd: Enable host kernel access to FPMR arm64/cpufeature: Hook new identification registers up to cpufeature docs: perf: Fix build warning of hisi-pcie-pmu.rst perf: starfive: Only allow COMPILE_TEST for 64-bit architectures MAINTAINERS: Add entry for StarFive StarLink PMU docs: perf: Add description for StarFive's StarLink PMU dt-bindings: perf: starfive: Add JH8100 StarLink PMU perf: starfive: Add StarLink PMU support docs: perf: Update usage for target filter of hisi-pcie-pmu ...
| * | rust: Refactor the build target to allow the use of builtin targetsJamie Cunliffe2024-02-091-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Eventually we want all architectures to be using the target as defined by rustc. However currently some architectures can't do that and are using the target.json specification. This puts in place the foundation to allow the use of the builtin target definition or a target.json specification. Signed-off-by: Jamie Cunliffe <Jamie.Cunliffe@arm.com> Acked-by: Masahiro Yamada <masahiroy@kernel.org> Tested-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20231020155056.3495121-2-Jamie.Cunliffe@arm.com [catalin.marinas@arm.com: squashed loongarch ifneq fix from WANG Rui] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* | | Merge tag 'x86-core-2024-03-11' of ↵Linus Torvalds2024-03-121-6/+5
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core x86 updates from Ingo Molnar: - The biggest change is the rework of the percpu code, to support the 'Named Address Spaces' GCC feature, by Uros Bizjak: - This allows C code to access GS and FS segment relative memory via variables declared with such attributes, which allows the compiler to better optimize those accesses than the previous inline assembly code. - The series also includes a number of micro-optimizations for various percpu access methods, plus a number of cleanups of %gs accesses in assembly code. - These changes have been exposed to linux-next testing for the last ~5 months, with no known regressions in this area. - Fix/clean up __switch_to()'s broken but accidentally working handling of FPU switching - which also generates better code - Propagate more RIP-relative addressing in assembly code, to generate slightly better code - Rework the CPU mitigations Kconfig space to be less idiosyncratic, to make it easier for distros to follow & maintain these options - Rework the x86 idle code to cure RCU violations and to clean up the logic - Clean up the vDSO Makefile logic - Misc cleanups and fixes * tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) x86/idle: Select idle routine only once x86/idle: Let prefer_mwait_c1_over_halt() return bool x86/idle: Cleanup idle_setup() x86/idle: Clean up idle selection x86/idle: Sanitize X86_BUG_AMD_E400 handling sched/idle: Conditionally handle tick broadcast in default_idle_call() x86: Increase brk randomness entropy for 64-bit systems x86/vdso: Move vDSO to mmap region x86/vdso/kbuild: Group non-standard build attributes and primary object file rules together x86/vdso: Fix rethunk patching for vdso-image-{32,64}.o x86/retpoline: Ensure default return thunk isn't used at runtime x86/vdso: Use CONFIG_COMPAT_32 to specify vdso32 x86/vdso: Use $(addprefix ) instead of $(foreach ) x86/vdso: Simplify obj-y addition x86/vdso: Consolidate targets and clean-files x86/bugs: Rename CONFIG_RETHUNK => CONFIG_MITIGATION_RETHUNK x86/bugs: Rename CONFIG_CPU_SRSO => CONFIG_MITIGATION_SRSO x86/bugs: Rename CONFIG_CPU_IBRS_ENTRY => CONFIG_MITIGATION_IBRS_ENTRY x86/bugs: Rename CONFIG_CPU_UNRET_ENTRY => CONFIG_MITIGATION_UNRET_ENTRY x86/bugs: Rename CONFIG_SLS => CONFIG_MITIGATION_SLS ...
| * \ \ Merge branch 'x86/vdso' into x86/core, to resolve conflict and to prepare ↵Ingo Molnar2024-02-221-2/+1
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | for dependent changes Conflicts: arch/x86/entry/vdso/Makefile We also want to change arch/x86/entry/vdso/Makefile in a followup commit, so merge the trees for this. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | x86/vdso: Use CONFIG_COMPAT_32 to specify vdso32Masahiro Yamada2024-02-081-2/+1
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In arch/x86/Kconfig, COMPAT_32 is defined as (IA32_EMULATION || X86_32). Use it to eliminate redundancy in Makefile. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231121235701.239606-5-masahiroy@kernel.org
| * | | Merge branch 'x86/bugs' into x86/core, to pick up pending changes before ↵Ingo Molnar2024-02-141-4/+4
| |\ \ \ | | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | dependent patches Merge in pending alternatives patching infrastructure changes, before applying more patches. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | x86/bugs: Rename CONFIG_RETHUNK => CONFIG_MITIGATION_RETHUNKBreno Leitao2024-01-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Step 10/10 of the namespace unification of CPU mitigations related Kconfig options. [ mingo: Added one more case. ] Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231121160740.1249350-11-leitao@debian.org
| | * | x86/bugs: Rename CONFIG_SLS => CONFIG_MITIGATION_SLSBreno Leitao2024-01-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Step 6/10 of the namespace unification of CPU mitigations related Kconfig options. Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231121160740.1249350-7-leitao@debian.org
| | * | x86/bugs: Rename CONFIG_RETPOLINE => CONFIG_MITIGATION_RETPOLINEBreno Leitao2024-01-101-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Step 5/10 of the namespace unification of CPU mitigations related Kconfig options. [ mingo: Converted a few more uses in comments/messages as well. ] Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Ariel Miculas <amiculas@cisco.com> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231121160740.1249350-6-leitao@debian.org
* | | | Merge tag 'x86-build-2024-03-11' of ↵Linus Torvalds2024-03-121-0/+3
|\ \ \ \ | |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 build updates from Ingo Molnar: - Reduce <asm/bootparam.h> dependencies - Simplify <asm/efi.h> - Unify *_setup_data definitions into <asm/setup_data.h> - Reduce the size of <asm/bootparam.h> * tag 'x86-build-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Do not include <asm/bootparam.h> in several files x86/efi: Implement arch_ima_efi_boot_mode() in source file x86/setup: Move internal setup_data structures into setup_data.h x86/setup: Move UAPI setup structures into setup_data.h
| * | | x86/setup: Move internal setup_data structures into setup_data.hThomas Zimmermann2024-01-301-0/+3
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move struct_efi_setup_data in order to unify duplicated definition of the data structure in a single place. Also silence clang's warnings about GNU extensions in real-mode code which might occur from the changed includes. [ bp: Massage commit message. ] Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240112095000.8952-3-tzimmermann@suse.de
* | | kbuild: use 4-space indentation when followed by conditionalsMasahiro Yamada2024-02-141-4/+4
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GNU Make manual [1] clearly forbids a tab at the beginning of the conditional directive line: "Extra spaces are allowed and ignored at the beginning of the conditional directive line, but a tab is not allowed." This will not work for the next release of GNU Make, hence commit 82175d1f9430 ("kbuild: Replace tabs with spaces when followed by conditionals") replaced the inappropriate tabs with 8 spaces. However, the 8-space indentation cannot be visually distinguished. Linus suggested 2-4 spaces for those nested if-statements. [2] This commit redoes the replacement with 4 spaces. [1]: https://www.gnu.org/software/make/manual/make.html#Conditional-Syntax [2]: https://lore.kernel.org/all/CAHk-=whJKZNZWsa-VNDKafS_VfY4a5dAjG-r8BZgWk_a-xSepw@mail.gmail.com/ Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* | kbuild: Replace tabs with spaces when followed by conditionalsDmitry Goncharov2024-01-311-5/+5
|/ | | | | | | | | | | | | | | | | | | | | | | | This is needed for the future (post make-4.4.1) versions of gnu make. Starting from https://git.savannah.gnu.org/cgit/make.git/commit/?id=07fcee35f058a876447c8a021f9eb1943f902534 gnu make won't allow conditionals to follow recipe prefix. For example there is a tab followed by ifeq on line 324 in the root Makefile. With the new make this conditional causes the following $ make cpu.o /home/dgoncharov/src/linux-kbuild/Makefile:2063: *** missing 'endif'. Stop. make: *** [Makefile:240: __sub-make] Error 2 This patch replaces tabs followed by conditionals with 8 spaces. See https://savannah.gnu.org/bugs/?64185 and https://savannah.gnu.org/bugs/?64259 for details. Signed-off-by: Dmitry Goncharov <dgoncharov@users.sf.net> Reported-by: Martin Dorey <martin.dorey@hitachivantara.com> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* Merge tag 'kbuild-v6.7' of ↵Linus Torvalds2023-11-041-3/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Implement the binary search in modpost for faster symbol lookup - Respect HOSTCC when linking host programs written in Rust - Change the binrpm-pkg target to generate kernel-devel RPM package - Fix endianness issues for tee and ishtp MODULE_DEVICE_TABLE - Unify vdso_install rules - Remove unused __memexit* annotations - Eliminate stale whitelisting for __devinit/__devexit from modpost - Enable dummy-tools to handle the -fpatchable-function-entry flag - Add 'userldlibs' syntax * tag 'kbuild-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits) kbuild: support 'userldlibs' syntax kbuild: dummy-tools: pretend we understand -fpatchable-function-entry kbuild: Correct missing architecture-specific hyphens modpost: squash ALL_{INIT,EXIT}_TEXT_SECTIONS to ALL_TEXT_SECTIONS modpost: merge sectioncheck table entries regarding init/exit sections modpost: use ALL_INIT_SECTIONS for the section check from DATA_SECTIONS modpost: disallow the combination of EXPORT_SYMBOL and __meminit* modpost: remove EXIT_SECTIONS macro modpost: remove MEM_INIT_SECTIONS macro modpost: remove more symbol patterns from the section check whitelist modpost: disallow *driver to reference .meminit* sections linux/init: remove __memexit* annotations modpost: remove ALL_EXIT_DATA_SECTIONS macro kbuild: simplify cmd_ld_multi_m kbuild: avoid too many execution of scripts/pahole-flags.sh kbuild: remove ARCH_POSTLINK from module builds kbuild: unify no-compiler-targets and no-sync-config-targets kbuild: unify vdso_install rules docs: kbuild: add INSTALL_DTBS_PATH UML: remove unused cmd_vdso_install ...
| * kbuild: unify vdso_install rulesMasahiro Yamada2023-10-281-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, there is no standard implementation for vdso_install, leading to various issues: 1. Code duplication Many architectures duplicate similar code just for copying files to the install destination. Some architectures (arm, sparc, x86) create build-id symlinks, introducing more code duplication. 2. Unintended updates of in-tree build artifacts The vdso_install rule depends on the vdso files to install. It may update in-tree build artifacts. This can be problematic, as explained in commit 19514fc665ff ("arm, kbuild: make "make install" not depend on vmlinux"). 3. Broken code in some architectures Makefile code is often copied from one architecture to another without proper adaptation. 'make vdso_install' for parisc does not work. 'make vdso_install' for s390 installs vdso64, but not vdso32. To address these problems, this commit introduces a generic vdso_install rule. Architectures that support vdso_install need to define vdso-install-y in arch/*/Makefile. vdso-install-y lists the files to install. For example, arch/x86/Makefile looks like this: vdso-install-$(CONFIG_X86_64) += arch/x86/entry/vdso/vdso64.so.dbg vdso-install-$(CONFIG_X86_X32_ABI) += arch/x86/entry/vdso/vdsox32.so.dbg vdso-install-$(CONFIG_X86_32) += arch/x86/entry/vdso/vdso32.so.dbg vdso-install-$(CONFIG_IA32_EMULATION) += arch/x86/entry/vdso/vdso32.so.dbg These files will be installed to $(MODLIB)/vdso/ with the .dbg suffix, if exists, stripped away. vdso-install-y can optionally take the second field after the colon separator. This is needed because some architectures install a vdso file as a different base name. The following is a snippet from arch/arm64/Makefile. vdso-install-$(CONFIG_COMPAT_VDSO) += arch/arm64/kernel/vdso32/vdso.so.dbg:vdso32.so This will rename vdso.so.dbg to vdso32.so during installation. If such architectures change their implementation so that the base names match, this workaround will go away. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Sven Schnelle <svens@linux.ibm.com> # s390 Reviewed-by: Nicolas Schier <nicolas@fjasle.eu> Reviewed-by: Guo Ren <guoren@kernel.org> Acked-by: Helge Deller <deller@gmx.de> # parisc Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
* | Merge tag 'x86_tdx_for_6.7' of ↵Linus Torvalds2023-11-011-0/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 TDX updates from Dave Hansen: "The majority of this is a rework of the assembly and C wrappers that are used to talk to the TDX module and VMM. This is a nice cleanup in general but is also clearing the way for using this code when Linux is the TDX VMM. There are also some tidbits to make TDX guests play nicer with Hyper-V and to take advantage the hardware TSC. Summary: - Refactor and clean up TDX hypercall/module call infrastructure - Handle retrying/resuming page conversion hypercalls - Make sure to use the (shockingly) reliable TSC in TDX guests" [ TLA reminder: TDX is "Trust Domain Extensions", Intel's guest VM confidentiality technology ] * tag 'x86_tdx_for_6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/tdx: Mark TSC reliable x86/tdx: Fix __noreturn build warning around __tdx_hypercall_failed() x86/virt/tdx: Make TDX_MODULE_CALL handle SEAMCALL #UD and #GP x86/virt/tdx: Wire up basic SEAMCALL functions x86/tdx: Remove 'struct tdx_hypercall_args' x86/tdx: Reimplement __tdx_hypercall() using TDX_MODULE_CALL asm x86/tdx: Make TDX_HYPERCALL asm similar to TDX_MODULE_CALL x86/tdx: Extend TDX_MODULE_CALL to support more TDCALL/SEAMCALL leafs x86/tdx: Pass TDCALL/SEAMCALL input/output registers via a structure x86/tdx: Rename __tdx_module_call() to __tdcall() x86/tdx: Make macros of TDCALLs consistent with the spec x86/tdx: Skip saving output regs when SEAMCALL fails with VMFailInvalid x86/tdx: Zero out the missing RSI in TDX_HYPERCALL macro x86/tdx: Retry partially-completed page conversion hypercalls
| * | x86/virt/tdx: Wire up basic SEAMCALL functionsKai Huang2023-09-131-0/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intel Trust Domain Extensions (TDX) protects guest VMs from malicious host and certain physical attacks. A CPU-attested software module called 'the TDX module' runs inside a new isolated memory range as a trusted hypervisor to manage and run protected VMs. TDX introduces a new CPU mode: Secure Arbitration Mode (SEAM). This mode runs only the TDX module itself or other code to load the TDX module. The host kernel communicates with SEAM software via a new SEAMCALL instruction. This is conceptually similar to a guest->host hypercall, except it is made from the host to SEAM software instead. The TDX module establishes a new SEAMCALL ABI which allows the host to initialize the module and to manage VMs. The SEAMCALL ABI is very similar to the TDCALL ABI and leverages much TDCALL infrastructure. Wire up basic functions to make SEAMCALLs for the basic support of running TDX guests: __seamcall(), __seamcall_ret(), and __seamcall_saved_ret() for TDH.VP.ENTER. All SEAMCALLs involved in the basic TDX support don't use "callee-saved" registers as input and output, except the TDH.VP.ENTER. To start to support TDX, create a new arch/x86/virt/vmx/tdx/tdx.c for TDX host kernel support. Add a new Kconfig option CONFIG_INTEL_TDX_HOST to opt-in TDX host kernel support (to distinguish with TDX guest kernel support). So far only KVM uses TDX. Make the new config option depend on KVM_INTEL. Signed-off-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Isaku Yamahata <isaku.yamahata@intel.com> Link: https://lore.kernel.org/all/4db7c3fc085e6af12acc2932294254ddb3d320b3.1692096753.git.kai.huang%40intel.com
* | Merge tag 'rust-6.7' of https://github.com/Rust-for-Linux/linuxLinus Torvalds2023-10-311-0/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull rust updates from Miguel Ojeda: "A small one compared to the previous one in terms of features. In terms of lines, as usual, the 'alloc' version upgrade accounts for most of them. Toolchain and infrastructure: - Upgrade to Rust 1.73.0 This time around, due to how the kernel and Rust schedules have aligned, there are two upgrades in fact. They contain the fixes for a few issues we reported to the Rust project. In addition, a few cleanups indicated by the upgraded compiler or possible thanks to it. For instance, the compiler now detects redundant explicit links. - A couple changes to the Rust 'Makefile' so that it can be used with toybox tools, allowing Rust to be used in the Android kernel build. x86: - Enable IBT if enabled in C Documentation: - Add "The Rust experiment" section to the Rust index page MAINTAINERS: - Add Maintainer Entry Profile field ('P:'). - Update our 'W:' field to point to the webpage we have been building this year" * tag 'rust-6.7' of https://github.com/Rust-for-Linux/linux: docs: rust: add "The Rust experiment" section x86: Enable IBT in Rust if enabled in C rust: Use grep -Ev rather than relying on GNU grep rust: Use awk instead of recent xargs rust: upgrade to Rust 1.73.0 rust: print: use explicit link in documentation rust: task: remove redundant explicit link rust: kernel: remove `#[allow(clippy::new_ret_no_self)]` MAINTAINERS: add Maintainer Entry Profile field for Rust MAINTAINERS: update Rust webpage rust: upgrade to Rust 1.72.1 rust: arc: add explicit `drop()` around `Box::from_raw()`
| * | x86: Enable IBT in Rust if enabled in CMatthew Maurer2023-10-231-0/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These flags are not made conditional on compiler support because at the moment exactly one version of rustc supported, and that one supports these flags. Building without these additional flags will manifest as objtool printing a large number of errors about missing ENDBR and if CFI is enabled (not currently possible) will result in incorrectly structured function prefixes. Signed-off-by: Matthew Maurer <mmaurer@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: "Peter Zijlstra (Intel)" <peterz@infradead.org> Link: https://lore.kernel.org/r/20231009224347.2076221-1-mmaurer@google.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
* / x86/boot: Compile boot code with -std=gnu11 tooAlexey Dobriyan2023-09-281-1/+1
|/ | | | | | | | | | | Use -std=gnu11 for consistency with main kernel code. It doesn't seem to change anything in vmlinux. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: H. Peter Anvin (Intel) <hpa@zytor.com> Link: https://lore.kernel.org/r/2058761e-12a4-4b2f-9690-3c3c1c9902a5@p183
* Merge tag 'kbuild-v6.6' of ↵Linus Torvalds2023-09-051-4/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Enable -Wenum-conversion warning option - Refactor the rpm-pkg target - Fix scripts/setlocalversion to consider annotated tags for rt-kernel - Add a jump key feature for the search menu of 'make nconfig' - Support Qt6 for 'make xconfig' - Enable -Wformat-overflow, -Wformat-truncation, -Wstringop-overflow, and -Wrestrict warnings for W=1 builds - Replace <asm/export.h> with <linux/export.h> for alpha, ia64, and sparc - Support DEB_BUILD_OPTIONS=parallel=N for the debian source package - Refactor scripts/Makefile.modinst and fix some modules_sign issues - Add a new Kconfig env variable to warn symbols that are not defined anywhere - Show help messages of config fragments in 'make help' * tag 'kbuild-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (62 commits) kconfig: fix possible buffer overflow kbuild: Show marked Kconfig fragments in "help" kconfig: add warn-unknown-symbols sanity check kbuild: dummy-tools: make MPROFILE_KERNEL checks work on BE Documentation/llvm: refresh docs modpost: Skip .llvm.call-graph-profile section check kbuild: support modules_sign for external modules as well kbuild: support 'make modules_sign' with CONFIG_MODULE_SIG_ALL=n kbuild: move more module installation code to scripts/Makefile.modinst kbuild: reduce the number of mkdir calls during modules_install kbuild: remove $(MODLIB)/source symlink kbuild: move depmod rule to scripts/Makefile.modinst kbuild: add modules_sign to no-{compiler,sync-config}-targets kbuild: do not run depmod for 'make modules_sign' kbuild: deb-pkg: support DEB_BUILD_OPTIONS=parallel=N in debian/rules alpha: remove <asm/export.h> alpha: replace #include <asm/export.h> with #include <linux/export.h> ia64: remove <asm/export.h> ia64: replace #include <asm/export.h> with #include <linux/export.h> sparc: remove <asm/export.h> ...
| * kbuild: Show marked Kconfig fragments in "help"Kees Cook2023-09-031-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the Kconfig fragments in kernel/configs and arch/*/configs that aren't used internally aren't discoverable through "make help", which consists of hard-coded lists of config fragments. Instead, list all the fragment targets that have a "# Help: " comment prefix so the targets can be generated dynamically. Add logic to the Makefile to search for and display the fragment and comment. Add comments to fragments that are intended to be direct targets. Signed-off-by: Kees Cook <keescook@chromium.org> Co-developed-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Reviewed-by: Nicolas Schier <nicolas@fjasle.eu> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* | Merge drm/drm-next into drm-misc-nextThomas Zimmermann2023-07-241-0/+12
|\| | | | | | | | | | | Backmerging to get v6.5-rc2. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
| * x86/unwind/orc: Add ELF section with ORC version identifierOmar Sandoval2023-06-161-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commits ffb1b4a41016 ("x86/unwind/orc: Add 'signal' field to ORC metadata") and fb799447ae29 ("x86,objtool: Split UNWIND_HINT_EMPTY in two") changed the ORC format. Although ORC is internal to the kernel, it's the only way for external tools to get reliable kernel stack traces on x86-64. In particular, the drgn debugger [1] uses ORC for stack unwinding, and these format changes broke it [2]. As the drgn maintainer, I don't care how often or how much the kernel changes the ORC format as long as I have a way to detect the change. It suffices to store a version identifier in the vmlinux and kernel module ELF files (to use when parsing ORC sections from ELF), and in kernel memory (to use when parsing ORC from a core dump+symbol table). Rather than hard-coding a version number that needs to be manually bumped, Peterz suggested hashing the definitions from orc_types.h. If there is a format change that isn't caught by this, the hashing script can be updated. This patch adds an .orc_header allocated ELF section containing the 20-byte hash to vmlinux and kernel modules, along with the corresponding __start_orc_header and __stop_orc_header symbols in vmlinux. 1: https://github.com/osandov/drgn 2: https://github.com/osandov/drgn/issues/303 Fixes: ffb1b4a41016 ("x86/unwind/orc: Add 'signal' field to ORC metadata") Fixes: fb799447ae29 ("x86,objtool: Split UNWIND_HINT_EMPTY in two") Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lkml.kernel.org/r/aef9c8dc43915b886a8c48509a12ec1b006ca1ca.1686690801.git.osandov@osandov.com
* | fbdev: Split frame buffer support in FB and FB_CORE symbolsJavier Martinez Canillas2023-07-221-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | Currently the CONFIG_FB option has to be enabled even if no legacy fbdev drivers are needed (e.g: only to have support for framebuffer consoles). The DRM subsystem has a fbdev emulation layer, but depends on CONFIG_FB and so it can only be enabled if that dependency is enabled as well. That means fbdev drivers have to be explicitly disabled if users want to enable CONFIG_FB, only to use fbcon and/or the DRM fbdev emulation layer. This patch introduces a non-visible CONFIG_FB_CORE symbol that could be enabled just to have core support needed for CONFIG_DRM_FBDEV_EMULATION, allowing CONFIG_FB to be disabled (and automatically disabling all the fbdev drivers). Nothing from fb_backlight.o and fbmon.o is used by the DRM fbdev emulation layer so these two objects can be compiled out when CONFIG_FB is disabled. Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Helge Deller <deller@gmx.de> Link: https://patchwork.freedesktop.org/patch/msgid/20230719081544.741051-4-javierm@redhat.com
* x86/build: Make 64-bit defconfig the defaultArnd Bergmann2023-02-151-3/+3
| | | | | | | | | | | | | | Running 'make ARCH=x86 defconfig' on anything other than an x86_64 machine currently results in a 32-bit build, which is rarely what anyone wants these days. Change the default so that the 64-bit config gets used unless the user asks for i386_defconfig, uses ARCH=i386 or runs on a system that "uname -m" identifies as i386/i486/i586/i686. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20230215091706.1623070-1-arnd@kernel.org
* x86/build: Move '-mindirect-branch-cs-prefix' out of GCC-only blockNathan Chancellor2023-01-221-1/+1
| | | | | | | | | | | | | | LLVM 16 will have support for this flag so move it out of the GCC-only block to allow LLVM builds to take advantage of it. Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://github.com/ClangBuiltLinux/linux/issues/1665 Link: https://github.com/llvm/llvm-project/commit/6f867f9102838ebe314c1f3661fdf95700386e5a Link: https://lore.kernel.org/r/20230120165826.2469302-1-nathan@kernel.org
* Merge tag 'kbuild-v6.2' of ↵Linus Torvalds2022-12-191-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Support zstd-compressed debug info - Allow W=1 builds to detect objects shared among multiple modules - Add srcrpm-pkg target to generate a source RPM package - Make the -s option detection work for future GNU Make versions - Add -Werror to KBUILD_CPPFLAGS when CONFIG_WERROR=y - Allow W=1 builds to detect -Wundef warnings in any preprocessed files - Raise the minimum supported version of binutils to 2.25 - Use $(intcmp ...) to compare integers if GNU Make >= 4.4 is used - Use $(file ...) to read a file if GNU Make >= 4.2 is used - Print error if GNU Make older than 3.82 is used - Allow modpost to detect section mismatches with Clang LTO - Include vmlinuz.efi into kernel tarballs for arm64 CONFIG_EFI_ZBOOT=y * tag 'kbuild-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (29 commits) buildtar: fix tarballs with EFI_ZBOOT enabled modpost: Include '.text.*' in TEXT_SECTIONS padata: Mark padata_work_init() as __ref kbuild: ensure Make >= 3.82 is used kbuild: refactor the prerequisites of the modpost rule kbuild: change module.order to list *.o instead of *.ko kbuild: use .NOTINTERMEDIATE for future GNU Make versions kconfig: refactor Makefile to reduce process forks kbuild: add read-file macro kbuild: do not sort after reading modules.order kbuild: add test-{ge,gt,le,lt} macros Documentation: raise minimum supported version of binutils to 2.25 kbuild: add -Wundef to KBUILD_CPPFLAGS for W=1 builds kbuild: move -Werror from KBUILD_CFLAGS to KBUILD_CPPFLAGS kbuild: Port silent mode detection to future gnu make. init/version.c: remove #include <generated/utsrelease.h> firmware_loader: remove #include <generated/utsrelease.h> modpost: Mark uuid_le type to be suitable only for MEI kbuild: add ability to make source rpm buildable using koji kbuild: warn objects shared among multiple modules ...
| * kbuild: add test-{ge,gt,le,lt} macrosMasahiro Yamada2022-12-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GNU Make 4.4 introduced $(intcmp ...), which is useful to compare two integers without forking a new process. Add test-{ge,gt,le,lt} macros, which work more efficiently with GNU Make >= 4.4. For older Make versions, they fall back to the 'test' shell command. The first two parameters to $(intcmp ...) must not be empty. To avoid the syntax error, I appended '0' to them. Fortunately, '00' is treated as '0'. This is needed because CONFIG options may expand to an empty string when the kernel configuration is not included. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Palmer Dabbelt <palmer@rivosinc.com> # RISC-V Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
* | x86/ibt: Implement FineIBTPeter Zijlstra2022-11-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement an alternative CFI scheme that merges both the fine-grained nature of kCFI but also takes full advantage of the coarse grained hardware CFI as provided by IBT. To contrast: kCFI is a pure software CFI scheme and relies on being able to read text -- specifically the instruction *before* the target symbol, and does the hash validation *before* doing the call (otherwise control flow is compromised already). FineIBT is a software and hardware hybrid scheme; by ensuring every branch target starts with a hash validation it is possible to place the hash validation after the branch. This has several advantages: o the (hash) load is avoided; no memop; no RX requirement. o IBT WAIT-FOR-ENDBR state is a speculation stop; by placing the hash validation in the immediate instruction after the branch target there is a minimal speculation window and the whole is a viable defence against SpectreBHB. o Kees feels obliged to mention it is slightly more vulnerable when the attacker can write code. Obviously this patch relies on kCFI, but additionally it also relies on the padding from the call-depth-tracking patches. It uses this padding to place the hash-validation while the call-sites are re-written to modify the indirect target to be 16 bytes in front of the original target, thus hitting this new preamble. Notably, there is no hardware that needs call-depth-tracking (Skylake) and supports IBT (Tigerlake and onwards). Suggested-by: Joao Moreira (Intel) <joao@overdrivepizza.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20221027092842.634714496@infradead.org
* | x86/Kconfig: Introduce function paddingThomas Gleixner2022-10-171-0/+6
|/ | | | | | | | | | | | | | | | | Now that all functions are 16 byte aligned, add 16 bytes of NOP padding in front of each function. This prepares things for software call stack tracking and kCFI/FineIBT. This significantly increases kernel .text size, around 5.1% on a x86_64-defconfig-ish build. However, per the random access argument used for alignment, these 16 extra bytes are code that wouldn't be used. Performance measurements back this up by showing no significant performance regressions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220915111146.950884492@infradead.org
* Merge tag 'kbuild-v6.1' of ↵Linus Torvalds2022-10-101-5/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Remove potentially incomplete targets when Kbuid is interrupted by SIGINT etc in case GNU Make may miss to do that when stderr is piped to another program. - Rewrite the single target build so it works more correctly. - Fix rpm-pkg builds with V=1. - List top-level subdirectories in ./Kbuild. - Ignore auto-generated __kstrtab_* and __kstrtabns_* symbols in kallsyms. - Avoid two different modules in lib/zstd/ having shared code, which potentially causes building the common code as build-in and modular back-and-forth. - Unify two modpost invocations to optimize the build process. - Remove head-y syntax in favor of linker scripts for placing particular sections in the head of vmlinux. - Bump the minimal GNU Make version to 3.82. - Clean up misc Makefiles and scripts. * tag 'kbuild-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (41 commits) docs: bump minimal GNU Make version to 3.82 ia64: simplify esi object addition in Makefile Revert "kbuild: Check if linker supports the -X option" kbuild: rebuild .vmlinux.export.o when its prerequisite is updated kbuild: move modules.builtin(.modinfo) rules to Makefile.vmlinux_o zstd: Fixing mixed module-builtin objects kallsyms: ignore __kstrtab_* and __kstrtabns_* symbols kallsyms: take the input file instead of reading stdin kallsyms: drop duplicated ignore patterns from kallsyms.c kbuild: reuse mksysmap output for kallsyms mksysmap: update comment about __crc_* kbuild: remove head-y syntax kbuild: use obj-y instead extra-y for objects placed at the head kbuild: hide error checker logs for V=1 builds kbuild: re-run modpost when it is updated kbuild: unify two modpost invocations kbuild: move vmlinux.o rule to the top Makefile kbuild: move .vmlinux.objs rule to Makefile.modpost kbuild: list sub-directories in ./Kbuild Makefile.compiler: replace cc-ifversion with compiler-specific macros ...
| * kbuild: remove head-y syntaxMasahiro Yamada2022-10-021-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kbuild puts the objects listed in head-y at the head of vmlinux. Conventionally, we do this for head*.S, which contains the kernel entry point. A counter approach is to control the section order by the linker script. Actually, the code marked as __HEAD goes into the ".head.text" section, which is placed before the normal ".text" section. I do not know if both of them are needed. From the build system perspective, head-y is not mandatory. If you can achieve the proper code placement by the linker script only, it would be cleaner. I collected the current head-y objects into head-object-list.txt. It is a whitelist. My hope is it will be reduced in the long run. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
* | x86: enable initial Rust supportMiguel Ojeda2022-09-281-0/+10
|/ | | | | | | | | | | | | | | | Note that only x86_64 is covered and not all features nor mitigations are handled, but it is enough as a starting point and showcases the basics needed to add Rust support for a new architecture. Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com> Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com> Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com> Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com> Co-developed-by: David Gow <davidgow@google.com> Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
* asm goto: eradicate CC_HAS_ASM_GOTONick Desaulniers2022-08-211-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | GCC has supported asm goto since 4.5, and Clang has since version 9.0.0. The minimum supported versions of these tools for the build according to Documentation/process/changes.rst are 5.1 and 11.0.0 respectively. Remove the feature detection script, Kconfig option, and clean up some fallback code that is no longer supported. The removed script was also testing for a GCC specific bug that was fixed in the 4.7 release. Also remove workarounds for bpftrace using clang older than 9.0.0, since other BPF backend fixes are required at this point. Link: https://lore.kernel.org/lkml/CAK7LNATSr=BXKfkdW8f-H5VT_w=xBpT2ZQcZ7rm6JfkdE+QnmA@mail.gmail.com/ Link: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48637 Acked-by: Borislav Petkov <bp@suse.de> Suggested-by: Masahiro Yamada <masahiroy@kernel.org> Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lkdtm: Disable return thunks in rodata.cJosh Poimboeuf2022-07-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following warning was seen: WARNING: CPU: 0 PID: 0 at arch/x86/kernel/alternative.c:557 apply_returns (arch/x86/kernel/alternative.c:557 (discriminator 1)) Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc4-00008-gee88d363d156 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-4 04/01/2014 RIP: 0010:apply_returns (arch/x86/kernel/alternative.c:557 (discriminator 1)) Code: ff ff 74 cb 48 83 c5 04 49 39 ee 0f 87 81 fe ff ff e9 22 ff ff ff 0f 0b 48 83 c5 04 49 39 ee 0f 87 6d fe ff ff e9 0e ff ff ff <0f> 0b 48 83 c5 04 49 39 ee 0f 87 59 fe ff ff e9 fa fe ff ff 48 89 The warning happened when apply_returns() failed to convert "JMP __x86_return_thunk" to RET. It was instead a JMP to nowhere, due to the thunk relocation not getting resolved. That rodata.o code is objcopy'd to .rodata, and later memcpy'd, so relocations don't work (and are apparently silently ignored). LKDTM is only used for testing, so the naked RET should be fine. So just disable return thunks for that file. While at it, disable objtool and KCSAN for the file. Fixes: 0b53c374b9ef ("x86/retpoline: Use -mfunction-return") Reported-by: kernel test robot <oliver.sang@intel.com> Debugged-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/lkml/Ys58BxHxoDZ7rfpr@xsang-OptiPlex-9020/
* x86/retbleed: Add fine grained Kconfig knobsPeter Zijlstra2022-06-291-2/+6
| | | | | | | | | | Do fine-grained Kconfig for all the various retbleed parts. NOTE: if your compiler doesn't support return thunks this will silently 'upgrade' your mitigation to IBPB, you might not like this. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de>
* x86/retpoline: Use -mfunction-returnPeter Zijlstra2022-06-271-0/+2
| | | | | | | | | | | | | | | | | Utilize -mfunction-return=thunk-extern when available to have the compiler replace RET instructions with direct JMPs to the symbol __x86_return_thunk. This does not affect assembler (.S) sources, only C sources. -mfunction-return=thunk-extern has been available since gcc 7.3 and clang 15. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Borislav Petkov <bp@suse.de>
* Merge tag 'kbuild-v5.19' of ↵Linus Torvalds2022-05-261-2/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Add HOSTPKG_CONFIG env variable to allow users to override pkg-config - Support W=e as a shorthand for KCFLAGS=-Werror - Fix CONFIG_IKHEADERS build to support toybox cpio - Add scripts/dummy-tools/pahole to ease distro packagers' life - Suppress false-positive warnings from checksyscalls.sh for W=2 build - Factor out the common code of arch/*/boot/install.sh into scripts/install.sh - Support 'kernel-install' tool in scripts/prune-kernel - Refactor module-versioning to link the symbol versions at the final link of vmlinux and modules - Remove CONFIG_MODULE_REL_CRCS because module-versioning now works in an arch-agnostic way - Refactor modpost, Makefiles * tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (56 commits) genksyms: adjust the output format to modpost kbuild: stop merging *.symversions kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS modpost: extract symbol versions from *.cmd files modpost: add sym_find_with_module() helper modpost: change the license of EXPORT_SYMBOL to bool type modpost: remove left-over cross_compile declaration kbuild: record symbol versions in *.cmd files kbuild: generate a list of objects in vmlinux modpost: move *.mod.c generation to write_mod_c_files() modpost: merge add_{intree_flag,retpoline,staging_flag} to add_header scripts/prune-kernel: Use kernel-install if available kbuild: factor out the common installation code into scripts/install.sh modpost: split new_symbol() to symbol allocation and hash table addition modpost: make sym_add_exported() always allocate a new symbol modpost: make multiple export error modpost: dump Module.symvers in the same order of modules.order modpost: traverse the namespace_list in order modpost: use doubly linked list for dump_lists modpost: traverse unresolved symbols in order ...
| * kbuild: factor out the common installation code into scripts/install.shMasahiro Yamada2022-05-111-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many architectures have similar install.sh scripts. The first half is really generic; it verifies that the kernel image and System.map exist, then executes ~/bin/${INSTALLKERNEL} or /sbin/${INSTALLKERNEL} if available. The second half is kind of arch-specific; it copies the kernel image and System.map to the destination, but the code is slightly different. Factor out the generic part into scripts/install.sh. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nicolas Schier <n.schier@avm.de>