linux.git/arch/arm64/Makefile, branch master

arm64: Add detection code for broken .inst support in binutils

2016-12-06T15:54:21+00:00

Binutils version up to (and including) 2.25 have a pathological behaviour when it comes to mixing .inst directive and arithmetic involving labels. The assembler complains about non-constant expressions and compilation stops pretty quickly. In order to detect this and work around it, let's add a bit of detection code that will set the CONFIG_BROKEN_GAS_INST option should a broken gas be detected. Acked-by: Will Deacon Signed-off-by: Marc Zyngier Signed-off-by: Catalin Marinas

arm64: kernel: force ET_DYN ELF type for CONFIG_RELOCATABLE=y

2016-10-20T10:37:25+00:00

GNU ld used to set the ELF file type to ET_DYN for PIE executables, which is the same file type used for shared libraries. However, this was changed recently, and now PIE executables are emitted as ET_EXEC instead. The distinction is only relevant for ELF loaders, and so there is little reason to care about the difference when building the kernel, which is why the change has gone unnoticed until now. However, debuggers do use the ELF binary, and expect ET_EXEC type files to appear in memory at the exact offset described in the ELF metadata. This means source level debugging is no longer possible when KASLR is in effect or when executing the stub. So add the -shared LD option when building with CONFIG_RELOCATABLE=y. This forces the ELF file type to be set to ET_DYN (which is what you get when building with binutils 2.24 and earlier anyway), and has no other ill effects. Signed-off-by: Ard Biesheuvel Signed-off-by: Will Deacon

arm64: Set UTS_MACHINE in the Makefile

2016-08-31T11:31:38+00:00

The make rpm target depends on proper UTS_MACHINE definition. Also, use the variable in arch/arm64/kernel/setup.c, so that it's not accidentally removed in the future. Reported-and-tested-by: Fabian Vogt Signed-off-by: Michal Marek Signed-off-by: Will Deacon

arm64: errata: Pass --fix-cortex-a53-843419 to ld if workaround enabled

2016-08-26T10:33:22+00:00

Cortex-A53 erratum 843419 is worked around by the linker, although it is a configure-time option to GCC as to whether ld is actually asked to apply the workaround or not. This patch ensures that we pass --fix-cortex-a53-843419 to the linker when both CONFIG_ARM64_ERRATUM_843419=y and the linker supports the option. Acked-by: Ard Biesheuvel Signed-off-by: Will Deacon

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2016-08-06T12:58:59+00:00

Pull arm64 fixes from Will Deacon: - fix HugeTLB leak due to CoW and PTE_RDONLY mismatch - avoid accessing unmapped FDT fields when checking validity - correctly account for vDSO AUX entry in ARCH_DLINFO - fix kallsyms with absolute expressions in linker script - kill unnecessary symbol-based relocs in vmlinux * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: Fix copy-on-write referencing in HugeTLB arm64: mm: avoid fdt_check_header() before the FDT is fully mapped arm64: Define AT_VECTOR_SIZE_ARCH for ARCH_DLINFO arm64: relocatable: suppress R_AARCH64_ABS64 relocations in vmlinux arm64: vmlinux.lds: make __rela_offset and __dynsym_offset ABSOLUTE

arm64: relocatable: suppress R_AARCH64_ABS64 relocations in vmlinux

2016-07-29T09:45:01+00:00

The linker routines that we rely on to produce a relocatable PIE binary treat it as a shared ELF object in some ways, i.e., it emits symbol based R_AARCH64_ABS64 relocations into the final binary since doing so would be appropriate when linking a shared library that is subject to symbol preemption. (This means that an executable can override certain symbols that are exported by a shared library it is linked with, and that the shared library *must* update all its internal references as well, and point them to the version provided by the executable.) Symbol preemption does not occur for OS hosted PIE executables, let alone for vmlinux, and so we would prefer to get rid of these symbol based relocations. This would allow us to simplify the relocation routines, and to strip the .dynsym, .dynstr and .hash sections from the binary. (Note that these are tiny, and are placed in the .init segment, but they clutter up the vmlinux binary.) Note that these R_AARCH64_ABS64 relocations are only emitted for absolute references to symbols defined in the linker script, all other relocatable quantities are covered by anonymous R_AARCH64_RELATIVE relocations that simply list the offsets to all 64-bit values in the binary that need to be fixed up based on the offset between the link time and run time addresses. Fortunately, GNU ld has a -Bsymbolic option, which is intended for shared libraries to allow them to ignore symbol preemption, and unconditionally bind all internal symbol references to its own definitions. So set it for our PIE binary as well, and get rid of the asoociated sections and the relocation code that processes them. Signed-off-by: Ard Biesheuvel [will: fixed conflict with __dynsym_offset linker script entry] Signed-off-by: Will Deacon

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2016-07-27T18:16:05+00:00

Pull arm64 updates from Catalin Marinas: - Kexec support for arm64 - Kprobes support - Expose MIDR_EL1 and REVIDR_EL1 CPU identification registers to sysfs - Trapping of user space cache maintenance operations and emulation in the kernel (CPU errata workaround) - Clean-up of the early page tables creation (kernel linear mapping, EFI run-time maps) to avoid splitting larger blocks (e.g. pmds) into smaller ones (e.g. ptes) - VDSO support for CLOCK_MONOTONIC_RAW in clock_gettime() - ARCH_HAS_KCOV enabled for arm64 - Optimise IP checksum helpers - SWIOTLB optimisation to only allocate/initialise the buffer if the available RAM is beyond the 32-bit mask - Properly handle the "nosmp" command line argument - Fix for the initialisation of the CPU debug state during early boot - vdso-offsets.h build dependency workaround - Build fix when RANDOMIZE_BASE is enabled with MODULES off * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (64 commits) arm64: arm: Fix-up the removal of the arm64 regs_query_register_name() prototype arm64: Only select ARM64_MODULE_PLTS if MODULES=y arm64: mm: run pgtable_page_ctor() on non-swapper translation table pages arm64: mm: make create_mapping_late() non-allocating arm64: Honor nosmp kernel command line option arm64: Fix incorrect per-cpu usage for boot CPU arm64: kprobes: Add KASAN instrumentation around stack accesses arm64: kprobes: Cleanup jprobe_return arm64: kprobes: Fix overflow when saving stack arm64: kprobes: WARN if attempting to step with PSTATE.D=1 arm64: debug: remove unused local_dbg_{enable, disable} macros arm64: debug: remove redundant spsr manipulation arm64: debug: unmask PSTATE.D earlier arm64: localise Image objcopy flags arm64: ptrace: remove extra define for CPSR's E bit kprobes: Add arm64 case in kprobe example module arm64: Add kernel return probes support (kretprobes) arm64: Add trampoline code for kretprobes arm64: kprobes instruction simulation support arm64: Treat all entry code as non-kprobe-able ...

arm64: localise Image objcopy flags

2016-07-19T14:30:23+00:00

We currently define OBJCOPYFLAGS in the top-level arm64 Makefile, and thus these flags will be passed to all uses of objcopy, kernel-wide, for which they are not explicitly overridden. The flags we set are intended for converting vmlinux (and ELF) into Image (a raw binary), and thus the flags chosen are problematic for some other uses which do not expect a raw binary result, e.g. the upcoming lkdtm rodata test: http://www.openwall.com/lists/kernel-hardening/2016/06/08/2 This patch localises the objcopy flags such that they are only used for the vmlinux -> Image conversion. Signed-off-by: Mark Rutland Cc: Will Deacon Acked-by: Kees Cook Tested-by: Laura Abbott Signed-off-by: Catalin Marinas

arm64: fix vdso-offsets.h dependency

2016-07-11T16:10:11+00:00

arm64/kernel/{vdso,signal}.c include vdso-offsets.h, as well as any file that includes asm/vdso.h. Therefore, vdso-offsets.h must be generated before these files are compiled. The current rules in arm64/kernel/Makefile do not actually enforce this, because even though $(obj)/vdso is listed as a prerequisite for vdso-offsets.h, this does not result in the intended effect of building the vdso subdirectory (before all the other objects). As a consequence, depending on the order in which the rules are followed, vdso-offsets.h is updated or not before arm64/kernel/{vdso,signal}.o are built. The current rules also impose an unnecessary dependency on vdso-offsets.h for all arm64/kernel/*.o, resulting in unnecessary rebuilds. This is made obvious when using make -j: touch arch/arm64/kernel/vdso/gettimeofday.S && make -j$NCPUS arch/arm64/kernel will sometimes result in none of arm64/kernel/*.o being rebuilt, sometimes all of them, or even just some of them. It is quite difficult to ensure that a header is generated before it is used with recursive Makefiles by using normal rules. Instead, arch-specific generated headers are normally built in the archprepare recipe in the arch Makefile (see for instance arch/ia64/Makefile). Unfortunately, asm-offsets.h is included in gettimeofday.S, and must therefore be generated before vdso-offsets.h, which is not the case if archprepare is used. For this reason, a rule run after archprepare has to be used. This commit adds rules in arm64/Makefile to build vdso-offsets.h during the prepare step, ensuring that vdso-offsets.h is generated before building anything. It also removes the now-unnecessary dependencies on vdso-offsets.h in arm64/kernel/Makefile. Finally, it removes the duplication of asm-offsets.h between arm64/kernel/vdso/ and include/generated/ and makes include/generated/vdso-offsets.h a target in arm64/kernel/vdso/Makefile. Cc: Will Deacon Cc: Michal Marek Signed-off-by: Kevin Brodsky Signed-off-by: Catalin Marinas

arm64: fix boot image dependencies to not generate invalid images

2016-06-21T19:10:18+00:00

I fixed boot image dependencies for arch/arm in commit 3939f3345050 ("ARM: 8418/1: add boot image dependencies to not generate invalid images"). I see a similar problem for arch/arm64; "make -jN Image Image.gz" would sometimes end up generating bad images where N > 1. Fix the dependency in arch/arm64/Makefile to avoid the race between "make Image" and "make Image.*". Acked-by: Catalin Marinas Signed-off-by: Masahiro Yamada Signed-off-by: Will Deacon