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2024-05-14Makefile: remove redundant tool coverage variablesMasahiro Yamada
Now Kbuild provides reasonable defaults for objtool, sanitizers, and profilers. Remove redundant variables. Note: This commit changes the coverage for some objects: - include arch/mips/vdso/vdso-image.o into UBSAN, GCOV, KCOV - include arch/sparc/vdso/vdso-image-*.o into UBSAN - include arch/sparc/vdso/vma.o into UBSAN - include arch/x86/entry/vdso/extable.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso-image-*.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso32-setup.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vma.o into GCOV, KCOV - include arch/x86/um/vdso/vma.o into KASAN, GCOV, KCOV I believe these are positive effects because all of them are kernel space objects. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Roberto Sassu <roberto.sassu@huawei.com>
2024-05-10kbuild: use $(src) instead of $(srctree)/$(src) for source directoryMasahiro Yamada
Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for checked-in source files. It is merely a convention without any functional difference. In fact, $(obj) and $(src) are exactly the same, as defined in scripts/Makefile.build: src := $(obj) When the kernel is built in a separate output directory, $(src) does not accurately reflect the source directory location. While Kbuild resolves this discrepancy by specifying VPATH=$(srctree) to search for source files, it does not cover all cases. For example, when adding a header search path for local headers, -I$(srctree)/$(src) is typically passed to the compiler. This introduces inconsistency between upstream and downstream Makefiles because $(src) is used instead of $(srctree)/$(src) for the latter. To address this inconsistency, this commit changes the semantics of $(src) so that it always points to the directory in the source tree. Going forward, the variables used in Makefiles will have the following meanings: $(obj) - directory in the object tree $(src) - directory in the source tree (changed by this commit) $(objtree) - the top of the kernel object tree $(srctree) - the top of the kernel source tree Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced with $(src). Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2024-03-26riscv: hwprobe: do not produce frtace relocationVladimir Isaev
Such relocation causes crash of android linker similar to one described in commit e05d57dcb8c7 ("riscv: Fixup __vdso_gettimeofday broke dynamic ftrace"). Looks like this relocation is added by CONFIG_DYNAMIC_FTRACE which is disabled in the default android kernel. Before: readelf -rW arch/riscv/kernel/vdso/vdso.so: Relocation section '.rela.dyn' at offset 0xd00 contains 1 entry: Offset Info Type 0000000000000d20 0000000000000003 R_RISCV_RELATIVE objdump: 0000000000000c86 <__vdso_riscv_hwprobe@@LINUX_4.15>: c86: 0001 nop c88: 0001 nop c8a: 0001 nop c8c: 0001 nop c8e: e211 bnez a2,c92 <__vdso_riscv_hwprobe... After: readelf -rW arch/riscv/kernel/vdso/vdso.so: There are no relocations in this file. objdump: 0000000000000c86 <__vdso_riscv_hwprobe@@LINUX_4.15>: c86: e211 bnez a2,c8a <__vdso_riscv_hwprobe... c88: c6b9 beqz a3,cd6 <__vdso_riscv_hwprobe... c8a: e739 bnez a4,cd8 <__vdso_riscv_hwprobe... c8c: ffffd797 auipc a5,0xffffd Also disable SCS since it also should not be available in vdso. Fixes: aa5af0aa90ba ("RISC-V: Add hwprobe vDSO function and data") Signed-off-by: Roman Artemev <roman.artemev@syntacore.com> Signed-off-by: Vladimir Isaev <vladimir.isaev@syntacore.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Guo Ren <guoren@kernel.org> Link: https://lore.kernel.org/r/20240313085843.17661-1-vladimir.isaev@syntacore.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-17Merge tag 'riscv-for-linus-6.8-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for many new extensions in hwprobe, along with a handful of cleanups - Various cleanups to our page table handling code, so we alwayse use {READ,WRITE}_ONCE - Support for the which-cpus flavor of hwprobe - Support for XIP kernels has been resurrected * tag 'riscv-for-linus-6.8-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (52 commits) riscv: hwprobe: export Zicond extension riscv: hwprobe: export Zacas ISA extension riscv: add ISA extension parsing for Zacas dt-bindings: riscv: add Zacas ISA extension description riscv: hwprobe: export Ztso ISA extension riscv: add ISA extension parsing for Ztso use linux/export.h rather than asm-generic/export.h riscv: Remove SHADOW_OVERFLOW_STACK_SIZE macro riscv; fix __user annotation in save_v_state() riscv: fix __user annotation in traps_misaligned.c riscv: Select ARCH_WANTS_NO_INSTR riscv: Remove obsolete rv32_defconfig file riscv: Allow disabling of BUILTIN_DTB for XIP riscv: Fixed wrong register in XIP_FIXUP_FLASH_OFFSET macro riscv: Make XIP bootable again riscv: Fix set_direct_map_default_noflush() to reset _PAGE_EXEC riscv: Fix module_alloc() that did not reset the linear mapping permissions riscv: Fix wrong usage of lm_alias() when splitting a huge linear mapping riscv: Check if the code to patch lies in the exit section riscv: Use the same CPU operations for all CPUs ...
2024-01-03RISC-V: hwprobe: Introduce which-cpus flagAndrew Jones
Introduce the first flag for the hwprobe syscall. The flag basically reverses its behavior, i.e. instead of populating the values of keys for a given set of cpus, the set of cpus after the call is the result of finding a set which supports the values of the keys. In order to do this, we implement a pair compare function which takes the type of value (a single value vs. a bitmask of booleans) into consideration. We also implement vdso support for the new flag. Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20231122164700.127954-9-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-03RISC-V: hwprobe: Clarify cpus size parameterAndrew Jones
The "count" parameter associated with the 'cpus' parameter of the hwprobe syscall is the size in bytes of 'cpus'. Naming it 'cpu_count' may mislead users (it did me) to think it's the number of CPUs that are or can be represented by 'cpus' instead. This is particularly easy (IMO) to get wrong since 'cpus' is documented to be defined by CPU_SET(3) and CPU_SET(3) also documents a CPU_COUNT() (the number of CPUs in set) macro. CPU_SET(3) refers to the size of cpu sets with 'setsize'. Adopt 'cpusetsize' for the hwprobe parameter and specifically state it is in bytes in Documentation/riscv/hwprobe.rst to clarify. Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20231122164700.127954-7-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-11-23arch: vdso: consolidate gettime prototypesArnd Bergmann
The VDSO functions are defined as globals in the kernel sources but intended to be called from userspace, so there is no need to declare them in a kernel side header. Without a prototype, this now causes warnings such as arch/mips/vdso/vgettimeofday.c:14:5: error: no previous prototype for '__vdso_clock_gettime' [-Werror=missing-prototypes] arch/mips/vdso/vgettimeofday.c:28:5: error: no previous prototype for '__vdso_gettimeofday' [-Werror=missing-prototypes] arch/mips/vdso/vgettimeofday.c:36:5: error: no previous prototype for '__vdso_clock_getres' [-Werror=missing-prototypes] arch/mips/vdso/vgettimeofday.c:42:5: error: no previous prototype for '__vdso_clock_gettime64' [-Werror=missing-prototypes] arch/sparc/vdso/vclock_gettime.c:254:1: error: no previous prototype for '__vdso_clock_gettime' [-Werror=missing-prototypes] arch/sparc/vdso/vclock_gettime.c:282:1: error: no previous prototype for '__vdso_clock_gettime_stick' [-Werror=missing-prototypes] arch/sparc/vdso/vclock_gettime.c:307:1: error: no previous prototype for '__vdso_gettimeofday' [-Werror=missing-prototypes] arch/sparc/vdso/vclock_gettime.c:343:1: error: no previous prototype for '__vdso_gettimeofday_stick' [-Werror=missing-prototypes] Most architectures have already added workarounds for these by adding declarations somewhere, but since these are all compatible, we should really just have one copy, with an #ifdef check for the 32-bit vs 64-bit variant and use that everywhere. Unfortunately, the sparc an um versions are currently incompatible since they never added support for __vdso_clock_gettime64() in 32-bit userland. For the moment, I'm leaving this one out, as I can't easily test it and it requires a larger rework. Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-11-10Merge tag 'riscv-for-linus-6.7-mw2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: - Support for handling misaligned accesses in S-mode - Probing for misaligned access support is now properly cached and handled in parallel - PTDUMP now reflects the SW reserved bits, as well as the PBMT and NAPOT extensions - Performance improvements for TLB flushing - Support for many new relocations in the module loader - Various bug fixes and cleanups * tag 'riscv-for-linus-6.7-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits) riscv: Optimize bitops with Zbb extension riscv: Rearrange hwcap.h and cpufeature.h drivers: perf: Do not broadcast to other cpus when starting a counter drivers: perf: Check find_first_bit() return value of: property: Add fw_devlink support for msi-parent RISC-V: Don't fail in riscv_of_parent_hartid() for disabled HARTs riscv: Fix set_memory_XX() and set_direct_map_XX() by splitting huge linear mappings riscv: Don't use PGD entries for the linear mapping RISC-V: Probe misaligned access speed in parallel RISC-V: Remove __init on unaligned_emulation_finish() RISC-V: Show accurate per-hart isa in /proc/cpuinfo RISC-V: Don't rely on positional structure initialization riscv: Add tests for riscv module loading riscv: Add remaining module relocations riscv: Avoid unaligned access when relocating modules riscv: split cache ops out of dma-noncoherent.c riscv: Improve flush_tlb_kernel_range() riscv: Make __flush_tlb_range() loop over pte instead of flushing the whole tlb riscv: Improve flush_tlb_range() for hugetlb pages riscv: Improve tlb_flush() ...
2023-11-08Merge tag 'riscv-for-linus-6.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for cbo.zero in userspace - Support for CBOs on ACPI-based systems - A handful of improvements for the T-Head cache flushing ops - Support for software shadow call stacks - Various cleanups and fixes * tag 'riscv-for-linus-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (31 commits) RISC-V: hwprobe: Fix vDSO SIGSEGV riscv: configs: defconfig: Enable configs required for RZ/Five SoC riscv: errata: prefix T-Head mnemonics with th. riscv: put interrupt entries into .irqentry.text riscv: mm: Update the comment of CONFIG_PAGE_OFFSET riscv: Using TOOLCHAIN_HAS_ZIHINTPAUSE marco replace zihintpause riscv/mm: Fix the comment for swap pte format RISC-V: clarify the QEMU workaround in ISA parser riscv: correct pt_level name via pgtable_l5/4_enabled RISC-V: Provide pgtable_l5_enabled on rv32 clocksource: timer-riscv: Increase rating of clock_event_device for Sstc clocksource: timer-riscv: Don't enable/disable timer interrupt lkdtm: Fix CFI_BACKWARD on RISC-V riscv: Use separate IRQ shadow call stacks riscv: Implement Shadow Call Stack riscv: Move global pointer loading to a macro riscv: Deduplicate IRQ stack switching riscv: VMAP_STACK overflow detection thread-safe RISC-V: cacheflush: Initialize CBO variables on ACPI systems RISC-V: ACPI: RHCT: Add function to get CBO block sizes ...
2023-11-06riscv: Use SYM_*() assembly macros instead of deprecated onesClément Léger
ENTRY()/END()/WEAK() macros are deprecated and we should make use of the new SYM_*() macros [1] for better annotation of symbols. Replace the deprecated ones with the new ones and fix wrong usage of END()/ENDPROC() to correctly describe the symbols. [1] https://docs.kernel.org/core-api/asm-annotations.html Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20231024132655.730417-3-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-11-05Merge patch series "riscv: vdso.lds.S: some improvement"Palmer Dabbelt
Jisheng Zhang <jszhang@kernel.org> says: This series renews one of my last year RFC patch[1], tries to improve the vdso layout a bit. patch1 removes useless symbols patch2 merges .data section of vdso into .rodata because they are readonly patch3 is the real renew patch, it removes hardcoded 0x800 .text start addr. But I rewrite the commit msg per Andrew's suggestions and move move .note, .eh_frame_hdr, and .eh_frame between .rodata and .text to keep the actual code well away from the non-instruction data. * b4-shazam-merge: riscv: vdso.lds.S: remove hardcoded 0x800 .text start addr riscv: vdso.lds.S: merge .data section into .rodata section riscv: vdso.lds.S: drop __alt_start and __alt_end symbols Link: https://lore.kernel.org/linux-riscv/20221123161805.1579-1-jszhang@kernel.org/ [1] Link: https://lore.kernel.org/r/20230912072015.2424-1-jszhang@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-11-05riscv: vdso.lds.S: remove hardcoded 0x800 .text start addrJisheng Zhang
I believe the hardcoded 0x800 and related comments come from the long history VDSO_TEXT_OFFSET in x86 vdso code, but commit 5b9304933730 ("x86 vDSO: generate vdso-syms.lds") and commit f6b46ebf904f ("x86 vDSO: new layout") removes the comment and hard coding for x86. Similar as x86 and other arch, riscv doesn't need the rigid layout using VDSO_TEXT_OFFSET since it "no longer matters to the kernel". so we could remove the hard coding now, and removing it brings a small vdso.so and aligns with other architectures. Also, having enough separation between data and text is important for I-cache, so similar as x86, move .note, .eh_frame_hdr, and .eh_frame between .rodata and .text. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Link: https://lore.kernel.org/r/20230912072015.2424-4-jszhang@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-11-05riscv: vdso.lds.S: merge .data section into .rodata sectionJisheng Zhang
The .data section doesn't need to be separate from .rodata section, they are both readonly. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Link: https://lore.kernel.org/r/20230912072015.2424-3-jszhang@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-11-05riscv: vdso.lds.S: drop __alt_start and __alt_end symbolsJisheng Zhang
These two symbols are not used, remove them. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Tested-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Link: https://lore.kernel.org/r/20230912072015.2424-2-jszhang@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-11-02RISC-V: hwprobe: Fix vDSO SIGSEGVAndrew Jones
A hwprobe pair key is signed, but the hwprobe vDSO function was only checking that the upper bound was valid. In order to help avoid this type of problem in the future, and in anticipation of this check becoming more complicated with sparse keys, introduce and use a "key is valid" predicate function for the check. Fixes: aa5af0aa90ba ("RISC-V: Add hwprobe vDSO function and data") Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20231010165101.14942-2-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-10-28kbuild: unify vdso_install rulesMasahiro Yamada
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>
2023-10-27riscv: Implement Shadow Call StackSami Tolvanen
Implement CONFIG_SHADOW_CALL_STACK for RISC-V. When enabled, the compiler injects instructions to all non-leaf C functions to store the return address to the shadow stack and unconditionally load it again before returning, which makes it harder to corrupt the return address through a stack overflow, for example. The active shadow call stack pointer is stored in the gp register, which makes SCS incompatible with gp relaxation. Use --no-relax-gp to ensure gp relaxation is disabled and disable global pointer loading. Add SCS pointers to struct thread_info, implement SCS initialization, and task switching Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20230927224757.1154247-12-samitolvanen@google.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-20riscv: replace deprecated scall with ecallFangrui Song
scall is a deprecated alias for ecall. ecall is used in several places, so there is no assembler compatibility concern. Signed-off-by: Fangrui Song <maskray@google.com> Link: https://lore.kernel.org/r/20230423223210.126948-1-maskray@google.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-28Merge tag 'riscv-for-linus-6.4-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for runtime detection of the Svnapot extension - Support for Zicboz when clearing pages - We've moved to GENERIC_ENTRY - Support for !MMU on rv32 systems - The linear region is now mapped via huge pages - Support for building relocatable kernels - Support for the hwprobe interface - Various fixes and cleanups throughout the tree * tag 'riscv-for-linus-6.4-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (57 commits) RISC-V: hwprobe: Explicity check for -1 in vdso init RISC-V: hwprobe: There can only be one first riscv: Allow to downgrade paging mode from the command line dt-bindings: riscv: add sv57 mmu-type RISC-V: hwprobe: Remove __init on probe_vendor_features() riscv: Use --emit-relocs in order to move .rela.dyn in init riscv: Check relocations at compile time powerpc: Move script to check relocations at compile time in scripts/ riscv: Introduce CONFIG_RELOCATABLE riscv: Move .rela.dyn outside of init to avoid empty relocations riscv: Prepare EFI header for relocatable kernels riscv: Unconditionnally select KASAN_VMALLOC if KASAN riscv: Fix ptdump when KASAN is enabled riscv: Fix EFI stub usage of KASAN instrumented strcmp function riscv: Move DTB_EARLY_BASE_VA to the kernel address space riscv: Rework kasan population functions riscv: Split early and final KASAN population functions riscv: Use PUD/P4D/PGD pages for the linear mapping riscv: Move the linear mapping creation in its own function riscv: Get rid of riscv_pfn_base variable ...
2023-04-18RISC-V: Add hwprobe vDSO function and dataEvan Green
Add a vDSO function __vdso_riscv_hwprobe, which can sit in front of the riscv_hwprobe syscall and answer common queries. We stash a copy of static answers for the "all CPUs" case in the vDSO data page. This data is private to the vDSO, so we can decide later to change what's stored there or under what conditions we defer to the syscall. Currently all data can be discovered at boot, so the vDSO function answers all queries when the cpumask is set to the "all CPUs" hint. There's also a boolean in the data that lets the vDSO function know that all CPUs are the same. In that case, the vDSO will also answer queries for arbitrary CPU masks in addition to the "all CPUs" hint. Signed-off-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20230407231103.2622178-7-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-03-21vdso: Improve cmd_vdso_check to check all dynamic relocationsFangrui Song
The actual intention is that no dynamic relocation exists in the VDSO. For this the VDSO build validates that the resulting .so file does not have any relocations which are specified via $(ARCH_REL_TYPE_ABS) per architecture, which is fragile as e.g. ARM64 lacks an entry for R_AARCH64_RELATIVE. Aside of that ARCH_REL_TYPE_ABS is a misnomer as it checks for relative relocations too. However, some GNU ld ports produce unneeded R_*_NONE relocation entries. If a port fails to determine the exact .rel[a].dyn size, the trailing zeros become R_*_NONE relocations. E.g. ld's powerpc port recently fixed https://sourceware.org/bugzilla/show_bug.cgi?id=29540). R_*_NONE are generally a no-op in the dynamic loaders. So just ignore them. Remove the ARCH_REL_TYPE_ABS defines and just validate that the resulting .so file does not contain any R_* relocation entries except R_*_NONE. Signed-off-by: Fangrui Song <maskray@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> # for aarch64 Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> # for vDSO, aarch64 Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Link: https://lore.kernel.org/r/20230310190750.3323802-1-maskray@google.com
2023-01-31riscv: alternative: patch alternatives in the vDSOJisheng Zhang
Make it possible to use alternatives in the vDSO, so that better implementations can be used if possible. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Guo Ren <guoren@kernel.org> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20230128172856.3814-11-jszhang@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-11-29riscv: vdso: fix section overlapping under some conditionsJisheng Zhang
lkp reported a build error, I tried the config and can reproduce build error as below: VDSOLD arch/riscv/kernel/vdso/vdso.so.dbg ld.lld: error: section .note file range overlaps with .text >>> .note range is [0x7C8, 0x803] >>> .text range is [0x800, 0x1993] ld.lld: error: section .text file range overlaps with .dynamic >>> .text range is [0x800, 0x1993] >>> .dynamic range is [0x808, 0x937] ld.lld: error: section .note virtual address range overlaps with .text >>> .note range is [0x7C8, 0x803] >>> .text range is [0x800, 0x1993] Fix it by setting DISABLE_BRANCH_PROFILING which will disable branch tracing for vdso, thus avoid useless _ftrace_annotated_branch section and _ftrace_branch section. Although we can also fix it by removing the hardcoded .text begin address, but I think that's another story and should be put into another patch. Link: https://lore.kernel.org/lkml/202210122123.Cc4FPShJ-lkp@intel.com/#r Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Link: https://lore.kernel.org/r/20221102170254.1925-1-jszhang@kernel.org Fixes: ad5d1122b82f ("riscv: use vDSO common flow to reduce the latency of the time-related functions") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-11-10RISC-V: vdso: Do not add missing symbols to version section in linker scriptNathan Chancellor
Recently, ld.lld moved from '--undefined-version' to '--no-undefined-version' as the default, which breaks the compat vDSO build: ld.lld: error: version script assignment of 'LINUX_4.15' to symbol '__vdso_gettimeofday' failed: symbol not defined ld.lld: error: version script assignment of 'LINUX_4.15' to symbol '__vdso_clock_gettime' failed: symbol not defined ld.lld: error: version script assignment of 'LINUX_4.15' to symbol '__vdso_clock_getres' failed: symbol not defined These symbols are not present in the compat vDSO or the regular vDSO for 32-bit but they are unconditionally included in the version section of the linker script, which is prohibited with '--no-undefined-version'. Fix this issue by only including the symbols that are actually exported in the version section of the linker script. Link: https://github.com/ClangBuiltLinux/linux/issues/1756 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20221108171324.3377226-1-nathan@kernel.org/ Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-11-10riscv: vdso: fix build with llvmJisheng Zhang
Even after commit 89fd4a1df829 ("riscv: jump_label: mark arguments as const to satisfy asm constraints"), building with CC_OPTIMIZE_FOR_SIZE + LLVM=1 can reproduce below build error: CC arch/riscv/kernel/vdso/vgettimeofday.o In file included from <built-in>:4: In file included from lib/vdso/gettimeofday.c:5: In file included from include/vdso/datapage.h:17: In file included from include/vdso/processor.h:10: In file included from arch/riscv/include/asm/vdso/processor.h:7: In file included from include/linux/jump_label.h:112: arch/riscv/include/asm/jump_label.h:42:3: error: invalid operand for inline asm constraint 'i' " .option push \n\t" ^ 1 error generated. I think the problem is when "-Os" is passed as CFLAGS, it's removed by "CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os" which is introduced in commit e05d57dcb8c7 ("riscv: Fixup __vdso_gettimeofday broke dynamic ftrace"), thus no optimization at all for vgettimeofday.c arm64 does remove "-Os" as well, but it forces "-O2" after removing "-Os". I compared the generated vgettimeofday.o with "-O2" and "-Os", I think no big performance difference. So let's tell the kbuild not to remove "-Os" rather than follow arm64 style. vdso related performance can be improved a lot when building kernel with CC_OPTIMIZE_FOR_SIZE after this commit, ("-Os" VS no optimization) Fixes: e05d57dcb8c7 ("riscv: Fixup __vdso_gettimeofday broke dynamic ftrace") Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Tested-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20221031182943.2453-1-jszhang@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-04-26riscv: compat: vdso: Add COMPAT_VDSO base code implementationGuo Ren
There is no vgettimeofday supported in rv32 that makes simple to generate rv32 vdso code which only needs riscv64 compiler. Other architectures need change compiler or -m (machine parameter) to support vdso32 compiling. If rv32 support vgettimeofday (which cause C compile) in future, we would add CROSS_COMPILE to support that makes more requirement on compiler enviornment. linux-rv64/arch/riscv/kernel/compat_vdso/compat_vdso.so.dbg: file format elf64-littleriscv Disassembly of section .text: 0000000000000800 <__vdso_rt_sigreturn>: 800: 08b00893 li a7,139 804: 00000073 ecall 808: 0000 unimp ... 000000000000080c <__vdso_getcpu>: 80c: 0a800893 li a7,168 810: 00000073 ecall 814: 8082 ret ... 0000000000000818 <__vdso_flush_icache>: 818: 10300893 li a7,259 81c: 00000073 ecall 820: 8082 ret linux-rv32/arch/riscv/kernel/vdso/vdso.so.dbg: file format elf32-littleriscv Disassembly of section .text: 00000800 <__vdso_rt_sigreturn>: 800: 08b00893 li a7,139 804: 00000073 ecall 808: 0000 unimp ... 0000080c <__vdso_getcpu>: 80c: 0a800893 li a7,168 810: 00000073 ecall 814: 8082 ret ... 00000818 <__vdso_flush_icache>: 818: 10300893 li a7,259 81c: 00000073 ecall 820: 8082 ret Finally, reuse all *.S from vdso in compat_vdso that makes implementation clear and readable. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Link: https://lore.kernel.org/r/20220405071314.3225832-17-guoren@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2021-10-04riscv/vdso: Add support for time namespacesTong Tiangen
Implement generic vdso time namespace support which also enables time namespaces for riscv. This is quite similar to what arm64 does. selftest/timens test result: 1..10 ok 1 Passed for CLOCK_BOOTTIME (syscall) ok 2 Passed for CLOCK_BOOTTIME (vdso) ok 3 # SKIP CLOCK_BOOTTIME_ALARM isn't supported ok 4 # SKIP CLOCK_BOOTTIME_ALARM isn't supported ok 5 Passed for CLOCK_MONOTONIC (syscall) ok 6 Passed for CLOCK_MONOTONIC (vdso) ok 7 Passed for CLOCK_MONOTONIC_COARSE (syscall) ok 8 Passed for CLOCK_MONOTONIC_COARSE (vdso) ok 9 Passed for CLOCK_MONOTONIC_RAW (syscall) ok 10 Passed for CLOCK_MONOTONIC_RAW (vdso) # Totals: pass:8 fail:0 xfail:0 xpass:0 skip:2 error:0 Signed-off-by: Tong Tiangen <tongtiangen@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-10-02riscv/vdso: Move vdso data page up frontTong Tiangen
As commit 601255ae3c98 ("arm64: vdso: move data page before code pages"), the same issue exists on riscv, testcase is shown below, make sure that vdso.so is bigger than page size, struct timespec tp; clock_gettime(5, &tp); printf("tv_sec: %ld, tv_nsec: %ld\n", tp.tv_sec, tp.tv_nsec); without this patch, test result : tv_sec: 0, tv_nsec: 0 with this patch, test result : tv_sec: 1629271537, tv_nsec: 748000000 Move the vdso data page in front of the VDSO area to fix the issue. Fixes: ad5d1122b82fb ("riscv: use vDSO common flow to reduce the latency of the time-related functions") Signed-off-by: Tong Tiangen <tongtiangen@huawei.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-08-24riscv: explicitly use symbol offsets for VDSOSaleem Abdulrasool
The current implementation of the `__rt_sigaction` reference computed an absolute offset relative to the mapped base of the VDSO. While this can be handled in the medlow model, the medany model cannot handle this as it is meant to be position independent. The current implementation relied on the BFD linker relaxing the PC-relative relocation into an absolute relocation as it was a near-zero address allowing it to be referenced relative to `zero`. We now extract the offsets and create a generated header allowing the build with LLVM and lld to succeed as we no longer depend on the linker rewriting address references near zero. This change was largely modelled after the ARM64 target which does something similar. Signed-off-by: Saleem Abdulrasool <abdulras@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-08-24riscv: Enable Undefined Behavior Sanitizer UBSANJisheng Zhang
Select ARCH_HAS_UBSAN_SANITIZE_ALL in order to allow the user to enable CONFIG_UBSAN_SANITIZE_ALL and instrument the entire kernel for ubsan checks. VDSO is excluded because its build doesn't include the __ubsan_handle_*() functions from lib/ubsan.c, and the VDSO has no sane way to report errors even if it has definitions of these functions. Passed lib/test_ubsan.c test. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: vdso: fix and clean-up MakefileJisheng Zhang
Running "make" on an already compiled kernel tree will rebuild the kernel even without any modifications: CALL linux/scripts/checksyscalls.sh CALL linux/scripts/atomic/check-atomics.sh CHK include/generated/compile.h SO2S arch/riscv/kernel/vdso/vdso-syms.S AS arch/riscv/kernel/vdso/vdso-syms.o AR arch/riscv/kernel/vdso/built-in.a AR arch/riscv/kernel/built-in.a AR arch/riscv/built-in.a GEN .version CHK include/generated/compile.h UPD include/generated/compile.h CC init/version.o AR init/built-in.a LD vmlinux.o The reason is "Any target that utilizes if_changed must be listed in $(targets), otherwise the command line check will fail, and the target will always be built" as explained by Documentation/kbuild/makefiles.rst Fix this build bug by adding vdso-syms.S to $(targets) At the same time, there are two trivial clean up modifications: - the vdso-dummy.o is not needed any more after so remove it. - vdso.lds is a generated file, so it should be prefixed with $(obj)/ instead of $(src)/ Fixes: c2c81bb2f691 ("RISC-V: Fix the VDSO symbol generaton for binutils-2.35+") Cc: stable@vger.kernel.org Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26riscv: Use $(LD) instead of $(CC) to link vDSONathan Chancellor
Currently, the VDSO is being linked through $(CC). This does not match how the rest of the kernel links objects, which is through the $(LD) variable. When linking with clang, there are a couple of warnings about flags that will not be used during the link: clang-12: warning: argument unused during compilation: '-no-pie' [-Wunused-command-line-argument] clang-12: warning: argument unused during compilation: '-pg' [-Wunused-command-line-argument] '-no-pie' was added in commit 85602bea297f ("RISC-V: build vdso-dummy.o with -no-pie") to override '-pie' getting added to the ld command from distribution versions of GCC that enable PIE by default. It is technically no longer needed after commit c2c81bb2f691 ("RISC-V: Fix the VDSO symbol generaton for binutils-2.35+"), which removed vdso-dummy.o in favor of generating vdso-syms.S from vdso.so with $(NM) but this also resolves the issue in case it ever comes back due to having full control over the $(LD) command. '-pg' is for function tracing, it is not used during linking as clang states. These flags could be removed/filtered to fix the warnings but it is easier to just match the rest of the kernel and use $(LD) directly for linking. See commits fe00e50b2db8 ("ARM: 8858/1: vdso: use $(LD) instead of $(CC) to link VDSO") 691efbedc60d ("arm64: vdso: use $(LD) instead of $(CC) to link VDSO") 2ff906994b6c ("MIPS: VDSO: Use $(LD) instead of $(CC) to link VDSO") 2b2a25845d53 ("s390/vdso: Use $(LD) instead of $(CC) to link vDSO") for more information. The flags are converted to linker flags and '--eh-frame-hdr' is added to match what is added by GCC implicitly, which can be seen by adding '-v' to GCC's invocation. Additionally, since this area is being modified, use the $(OBJCOPY) variable instead of an open coded $(CROSS_COMPILE)objcopy so that the user's choice of objcopy binary is respected. Link: https://github.com/ClangBuiltLinux/linux/issues/803 Link: https://github.com/ClangBuiltLinux/linux/issues/970 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Fangrui Song <maskray@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-22riscv: Disable KSAN_SANITIZE for vDSOTobias Klauser
We use the generic C VDSO implementations of a handful of clock-related functions. When kasan is enabled this results in asan stub calls that are unlikely to be resolved by userspace, this just disables KASAN when building the VDSO. Verified the fix on a kernel with KASAN enabled using vDSO selftests. Link: https://lore.kernel.org/lkml/CACT4Y+ZNJBnkKHXUf=tm_yuowvZvHwN=0rmJ=7J+xFd+9r_6pQ@mail.gmail.com/ Tested-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Tested-by: Dmitry Vyukov <dvyukov@google.com> [Palmer: commit text] Fixes: ad5d1122b82f ("riscv: use vDSO common flow to reduce the latency of the time-related functions") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-25riscv: Explicitly specify the build id style in vDSO Makefile againNathan Chancellor
Commit a96843372331 ("kbuild: explicitly specify the build id style") explicitly set the build ID style to SHA1. Commit c2c81bb2f691 ("RISC-V: Fix the VDSO symbol generaton for binutils-2.35+") undid this change, likely unintentionally. Restore it so that the build ID style stays consistent across the tree regardless of linker. Fixes: c2c81bb2f691 ("RISC-V: Fix the VDSO symbol generaton for binutils-2.35+") Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Bill Wendling <morbo@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-11-06RISC-V: Fix the VDSO symbol generaton for binutils-2.35+Palmer Dabbelt
We were relying on GNU ld's ability to re-link executable files in order to extract our VDSO symbols. This behavior was deemed a bug as of binutils-2.35 (specifically the binutils-gdb commit a87e1817a4 ("Have the linker fail if any attempt to link in an executable is made."), but as that has been backported to at least Debian's binutils-2.34 in may manifest in other places. The previous version of this was a bit of a mess: we were linking a static executable version of the VDSO, containing only a subset of the input symbols, which we then linked into the kernel. This worked, but certainly wasn't a supported path through the toolchain. Instead this new version parses the textual output of nm to produce a symbol table. Both rely on near-zero addresses being linkable, but as we rely on weak undefined symbols being linkable elsewhere I don't view this as a major issue. Fixes: e2c0cdfba7f6 ("RISC-V: User-facing API") Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-10-09kbuild: explicitly specify the build id styleBill Wendling
ld's --build-id defaults to "sha1" style, while lld defaults to "fast". The build IDs are very different between the two, which may confuse programs that reference them. Signed-off-by: Bill Wendling <morbo@google.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-08-04riscv: disable stack-protector for vDSOTobias Klauser
Currently, building the vDSO with clang leads assembler errors like the following: /tmp/vgettimeofday-1ae0d2.s: Assembler messages: /tmp/vgettimeofday-1ae0d2.s:28: Error: bad expression /tmp/vgettimeofday-1ae0d2.s:28: Error: illegal operands `auipc a2,%got_pcrel_hi(__stack_chk_guard)' Disable the stack-protector for vDSO to fix these. Link: https://github.com/ClangBuiltLinux/linux/issues/1112 Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-07-30riscv: Allow building with kcov coverageTobias Klauser
Add ARCH_HAS_KCOV and HAVE_GCC_PLUGINS to the riscv Kconfig. Also disable instrumentation of some early boot code and vdso. Boot-tested on QEMU's riscv64 virt machine. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-25riscv: Fixup __vdso_gettimeofday broke dynamic ftraceGuo Ren
For linux-5.8-rc1, enable ftrace of riscv will cause boot panic: [ 2.388980] Run /sbin/init as init process [ 2.529938] init[39]: unhandled signal 4 code 0x1 at 0x0000003ff449e000 [ 2.531078] CPU: 0 PID: 39 Comm: init Not tainted 5.8.0-rc1-dirty #13 [ 2.532719] epc: 0000003ff449e000 ra : 0000003ff449e954 sp : 0000003fffedb900 [ 2.534005] gp : 00000000000e8528 tp : 0000003ff449d800 t0 : 000000000000001e [ 2.534965] t1 : 000000000000000a t2 : 0000003fffedb89e s0 : 0000003fffedb920 [ 2.536279] s1 : 0000003fffedb940 a0 : 0000003ff43d4b2c a1 : 0000000000000000 [ 2.537334] a2 : 0000000000000001 a3 : 0000000000000000 a4 : fffffffffbad8000 [ 2.538466] a5 : 0000003ff449e93a a6 : 0000000000000000 a7 : 0000000000000000 [ 2.539511] s2 : 0000000000000000 s3 : 0000003ff448412c s4 : 0000000000000010 [ 2.541260] s5 : 0000000000000016 s6 : 00000000000d0a30 s7 : 0000003fffedba70 [ 2.542152] s8 : 0000000000000000 s9 : 0000000000000000 s10: 0000003fffedb960 [ 2.543335] s11: 0000000000000000 t3 : 0000000000000000 t4 : 0000003fffedb8a0 [ 2.544471] t5 : 0000000000000000 t6 : 0000000000000000 [ 2.545730] status: 0000000000004020 badaddr: 00000000464c457f cause: 0000000000000002 [ 2.549867] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004 [ 2.551267] CPU: 0 PID: 1 Comm: init Not tainted 5.8.0-rc1-dirty #13 [ 2.552061] Call Trace: [ 2.552626] [<ffffffe00020374a>] walk_stackframe+0x0/0xc4 [ 2.553486] [<ffffffe0002039f4>] show_stack+0x40/0x4c [ 2.553995] [<ffffffe00054a6ae>] dump_stack+0x7a/0x98 [ 2.554615] [<ffffffe00020b9b8>] panic+0x114/0x2f4 [ 2.555395] [<ffffffe00020ebd6>] do_exit+0x89c/0x8c2 [ 2.555949] [<ffffffe00020f930>] do_group_exit+0x3a/0x90 [ 2.556715] [<ffffffe000219e08>] get_signal+0xe2/0x6e6 [ 2.557388] [<ffffffe000202d72>] do_notify_resume+0x6a/0x37a [ 2.558089] [<ffffffe000201c16>] ret_from_exception+0x0/0xc "ra:0x3ff449e954" is the return address of "call _mcount" in the prologue of __vdso_gettimeofday(). Without proper relocate, pc jmp to 0x0000003ff449e000 (vdso map base) with a illegal instruction trap. The solution comes from arch/arm64/kernel/vdso/Makefile: CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) - CC_FLAGS_SCS is ShadowCallStack feature in Clang and only implemented for arm64, no use for riscv. Fixes: ad5d1122b82f ("riscv: use vDSO common flow to reduce the latency of the time-related functions") Cc: stable@vger.kernel.org Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Reviewed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-25riscv: Add extern declarations for vDSO time-related functionsVincent Chen
Add extern declarations for vDSO time-related functions to notify the compiler these functions will be used in somewhere to avoid "no previous prototype" compile warning. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-25riscv: Add -fPIC option to CFLAGS_vgettimeofday.oVincent Chen
The time related vDSO functions use a variable, vdso_data, to access the vDSO data page to get the system time information. Because the vdso_data for CFLAGS_vgettimeofday.o is an external variable defined in vdso.o, the CFLAGS_vgettimeofday.o should be compiled with -fPIC to ensure that vdso_data is addressable. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-10riscv: use vDSO common flow to reduce the latency of the time-related functionsVincent Chen
Even if RISC-V has supported the vDSO feature, the latency of the functions for obtaining the system time is still expensive. It is because these functions still trigger a corresponding system call in the process, which slows down the response time. If we want to remove the system call to reduce the latency, the kernel should have the ability to output the system clock information to userspace. This patch introduces the vDSO common flow to enable the kernel to achieve the above feature and uses "rdtime" instruction to obtain the current time in the user space. Under this condition, the latency cost by the ecall from U-mode to S-mode can be eliminated. After applying this patch, the latency of gettimeofday() measured on the HiFive unleashed board can be reduced by %61. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-04riscv: add Linux note to vdsoAndreas Schwab
The Linux note in the vdso allows glibc to check the running kernel version without having to issue the uname syscall. Signed-off-by: Andreas Schwab <schwab@suse.de> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-04-21riscv: fix vdso build with lldIlie Halip
When building with the LLVM linker this error occurrs: LD arch/riscv/kernel/vdso/vdso-syms.o ld.lld: error: no input files This happens because the lld treats -R as an alias to -rpath, as opposed to ld where -R means --just-symbols. Use the long option name for compatibility between the two. Link: https://github.com/ClangBuiltLinux/linux/issues/805 Reported-by: Dmitry Golovin <dima@golovin.in> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Ilie Halip <ilie.halip@gmail.com> Reviewed-by: Fangrui Song <maskray@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-25.gitignore: add SPDX License IdentifierMasahiro Yamada
Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-18riscv: delete temporary filesIlie Halip
Temporary files used in the VDSO build process linger on even after make mrproper: vdso-dummy.o.tmp, vdso.so.dbg.tmp. Delete them once they're no longer needed. Signed-off-by: Ilie Halip <ilie.halip@gmail.com> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-07-31riscv: Fix perf record without libelf supportMao Han
This patch fix following perf record error by linking vdso.so with build id. perf.data perf.data.old [ perf record: Woken up 1 times to write data ] free(): double free detected in tcache 2 Aborted perf record use filename__read_build_id(util/symbol-minimal.c) to get build id when libelf is not supported. When vdso.so is linked without build id, the section size of PT_NOTE will be zero, buf size will realloc to zero and cause memory corruption. Signed-off-by: Mao Han <han_mao@c-sky.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 286Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation version 2 this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 97 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.025053186@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-29riscv: vdso: drop unnecessary cc-ldoptionNick Desaulniers
Towards the goal of removing cc-ldoption, it seems that --hash-style= was added to binutils 2.17.50.0.2 in 2006. The minimal required version of binutils for the kernel according to Documentation/process/changes.rst is 2.20. Link: https://gcc.gnu.org/ml/gcc/2007-01/msg01141.html Cc: clang-built-linux@googlegroups.com Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>