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* x86-64: Remove sysdeps/x86_64/x32/dl-machine.hH.J. Lu2024-07-251-11/+16
| | | | | | | | | | | | | | | | | | | | Remove sysdeps/x86_64/x32/dl-machine.h by folding x32 ARCH_LA_PLTENTER, ARCH_LA_PLTEXIT and RTLD_START into sysdeps/x86_64/dl-machine.h. There are no regressions on x86-64 nor x32. There are no changes in x86-64 _dl_start_user. On x32, _dl_start_user changes are <_dl_start_user>: mov %eax,%r12d + mov %esp,%r13d mov (%rsp),%edx mov %edx,%esi - mov %esp,%r13d and $0xfffffff0,%esp mov 0x0(%rip),%edi # <_dl_start_user+0x14> lea 0x8(%r13,%rdx,4),%ecx Signed-off-by: H.J. Lu <hjl.tools@gmail.com> Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* x86_64: Reformat elf_machine_relaXin Wang2024-05-271-4/+5
| | | | | | | | | | | A space is added before the left bracket of the x86_64 elf_machine_rela function, in order to harmonize with the rest of the implementation of the function and to make it easier to retrieve the function. The lines where the function definition is located has been re-indented, as well as its left curly bracket placed in the correct position. Signed-off-by: Xin Wang <yw987194828@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* x86: Update _dl_tlsdesc_dynamic to preserve caller-saved registersH.J. Lu2024-02-281-15/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | Compiler generates the following instruction sequence for GNU2 dynamic TLS access: leaq tls_var@TLSDESC(%rip), %rax call *tls_var@TLSCALL(%rax) or leal tls_var@TLSDESC(%ebx), %eax call *tls_var@TLSCALL(%eax) CALL instruction is transparent to compiler which assumes all registers, except for EFLAGS and RAX/EAX, are unchanged after CALL. When _dl_tlsdesc_dynamic is called, it calls __tls_get_addr on the slow path. __tls_get_addr is a normal function which doesn't preserve any caller-saved registers. _dl_tlsdesc_dynamic saved and restored integer caller-saved registers, but didn't preserve any other caller-saved registers. Add _dl_tlsdesc_dynamic IFUNC functions for FNSAVE, FXSAVE, XSAVE and XSAVEC to save and restore all caller-saved registers. This fixes BZ #31372. Add GLRO(dl_x86_64_runtime_resolve) with GLRO(dl_x86_tlsdesc_dynamic) to optimize elf_machine_runtime_setup. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* x86-64/cet: Make CET feature check specific to Linux/x86H.J. Lu2024-01-111-4/+5
| | | | | | CET feature bits in TCB, which are Linux specific, are used to check if CET features are active. Move CET feature check to Linux/x86 directory. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* x32: Handle displacement overflow in PLT rewrite [BZ #31218]H.J. Lu2024-01-061-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PLT rewrite calculated displacement with ElfW(Addr) disp = value - branch_start - JMP32_INSN_SIZE; On x32, displacement from 0xf7fbe060 to 0x401030 was calculated as unsigned int disp = 0x401030 - 0xf7fbe060 - 5; with disp == 0x8442fcb and caused displacement overflow. The PLT entry was changed to: 0xf7fbe060 <+0>: e9 cb 2f 44 08 jmp 0x401030 0xf7fbe065 <+5>: cc int3 0xf7fbe066 <+6>: cc int3 0xf7fbe067 <+7>: cc int3 0xf7fbe068 <+8>: cc int3 0xf7fbe069 <+9>: cc int3 0xf7fbe06a <+10>: cc int3 0xf7fbe06b <+11>: cc int3 0xf7fbe06c <+12>: cc int3 0xf7fbe06d <+13>: cc int3 0xf7fbe06e <+14>: cc int3 0xf7fbe06f <+15>: cc int3 x32 has 32-bit address range, but it doesn't wrap address around at 4GB, JMP target was changed to 0x100401030 (0xf7fbe060LL + 0x8442fcbLL + 5), which is above 4GB. Always use uint64_t to calculate displacement. This fixes BZ #31218. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* elf: Add ELF_DYNAMIC_AFTER_RELOC to rewrite PLTH.J. Lu2024-01-051-1/+215
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add ELF_DYNAMIC_AFTER_RELOC to allow target specific processing after relocation. For x86-64, add #define DT_X86_64_PLT (DT_LOPROC + 0) #define DT_X86_64_PLTSZ (DT_LOPROC + 1) #define DT_X86_64_PLTENT (DT_LOPROC + 3) 1. DT_X86_64_PLT: The address of the procedure linkage table. 2. DT_X86_64_PLTSZ: The total size, in bytes, of the procedure linkage table. 3. DT_X86_64_PLTENT: The size, in bytes, of a procedure linkage table entry. With the r_addend field of the R_X86_64_JUMP_SLOT relocation set to the memory offset of the indirect branch instruction. Define ELF_DYNAMIC_AFTER_RELOC for x86-64 to rewrite the PLT section with direct branch after relocation when the lazy binding is disabled. PLT rewrite is disabled by default since SELinux may disallow modifying code pages and ld.so can't detect it in all cases. Use $ export GLIBC_TUNABLES=glibc.cpu.plt_rewrite=1 to enable PLT rewrite with 32-bit direct jump at run-time or $ export GLIBC_TUNABLES=glibc.cpu.plt_rewrite=2 to enable PLT rewrite with 32-bit direct jump and on APX processors with 64-bit absolute jump at run-time. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* Update copyright dates with scripts/update-copyrightsPaul Eggert2024-01-011-1/+1
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* x86/cet: Enable shadow stack during startupH.J. Lu2024-01-011-2/+10
| | | | | | | | | | | | | | | | | | | | | | | Previously, CET was enabled by kernel before passing control to user space and the startup code must disable CET if applications or shared libraries aren't CET enabled. Since the current kernel only supports shadow stack and won't enable shadow stack before passing control to user space, we need to enable shadow stack during startup if the application and all shared library are shadow stack enabled. There is no need to disable shadow stack at startup. Shadow stack can only be enabled in a function which will never return. Otherwise, shadow stack will underflow at the function return. 1. GL(dl_x86_feature_1) is set to the CET features which are supported by the processor and are not disabled by the tunable. Only non-zero features in GL(dl_x86_feature_1) should be enabled. After enabling shadow stack with ARCH_SHSTK_ENABLE, ARCH_SHSTK_STATUS is used to check if shadow stack is really enabled. 2. Use ARCH_SHSTK_ENABLE in RTLD_START in dynamic executable. It is safe since RTLD_START never returns. 3. Call arch_prctl (ARCH_SHSTK_ENABLE) from ARCH_SETUP_TLS in static executable. Since the start function using ARCH_SETUP_TLS never returns, it is safe to enable shadow stack in ARCH_SETUP_TLS.
* elf: Remove LD_PROFILE for static binariesAdhemerval Zanella2023-11-211-0/+2
| | | | | | | | | | | The _dl_non_dynamic_init does not parse LD_PROFILE, which does not enable profile for dlopen objects. Since dlopen is deprecated for static objects, it is better to remove the support. It also allows to trim down libc.a of profile support. Checked on x86_64-linux-gnu. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* Update copyright dates with scripts/update-copyrightsJoseph Myers2023-01-061-1/+1
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* x86-64: Only define used SSE/AVX/AVX512 run-time resolversH.J. Lu2022-06-271-4/+8
| | | | | | | When glibc is built with x86-64 ISA level v3, SSE run-time resolvers aren't used. For x86-64 ISA level v4 build, both SSE and AVX resolvers are unused. Check the minimum x86-64 ISA level to exclude the unused run-time resolvers.
* x86-64: Handle fewer relocation types for RTLD_BOOTSTRAPFangrui Song2022-06-161-26/+6
| | | | | | | | | | The RTLD_BOOTSTRAP branch is used to relocate ld.so itself. It only needs to handle RELATIVE, GLOB_DAT, and JUMP_SLOT. RELATIVE has been handled (by _ELF_DYNAMIC_DO_RELOC due to DT_RELACOUNT, or RELR), so the switch statement only needs to handle GLOB_DAT and JUMP_SLOT. We can drop these `#if[n]def RTLD_BOOTSTRAP` and add a large `# ifndef RTLD_BOOTSTRAP` instead.
* elf: Remove ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATAFangrui Song2022-06-151-6/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | If an executable has copy relocations for extern protected data, that can only work if the library containing the definition is built with assumptions (a) the compiler emits GOT-generating relocations (b) the linker produces R_*_GLOB_DAT instead of R_*_RELATIVE. Otherwise the library uses its own definition directly and the executable accesses a stale copy. Note: the GOT relocations defeat the purpose of protected visibility as an optimization, but allow rtld to make the executable and library use the same copy when copy relocations are present, but it turns out this never worked perfectly. ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA has strange semantics when both a.so and b.so define protected var and the executable copy relocates var: b.so accesses its own copy even with GLOB_DAT. The behavior change is from commit 62da1e3b00b51383ffa7efc89d8addda0502e107 (x86) and then copied to nios2 (ae5eae7cfc9c4a8297ff82ec6b794faca1976ecc) and arc (0e7d930c4c11de896fe807f67fa1eb756c9c1e05). Without ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA, b.so accesses the copy relocated data like a.so. There is now a warning for copy relocation on protected symbol since commit 7374c02b683b7110b853a32496a619410364d70b. It's extremely unlikely anyone relies on the ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA behavior, so let's remove it: this removes a check in the symbol lookup code.
* x86_64: Remove _dl_skip_args usageAdhemerval Zanella2022-05-301-11/+2
| | | | | | | | | | | Since ad43cac44a the generic code already shuffles the argv/envp/auxv on the stack to remove the ld.so own arguments and thus _dl_skip_args is always 0. So there is no need to adjust the argc or argv. Checked on x86_64-linux-gnu and i686-linux-gnu. Reviewed-by: H.J. Lu <hjl.tools@gmail.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* x86-64: Ignore r_addend for R_X86_64_GLOB_DAT/R_X86_64_JUMP_SLOTH.J. Lu2022-05-261-2/+4
| | | | | | | | According to x86-64 psABI, r_addend should be ignored for R_X86_64_GLOB_DAT and R_X86_64_JUMP_SLOT. Since linkers always set their r_addends to 0, we can ignore their r_addends. Reviewed-by: Fangrui Song <maskray@google.com>
* Remove -z combreloc and HAVE_Z_COMBRELOCFangrui Song2022-04-041-16/+2
| | | | | | | | | | | | | -z combreloc has been the default regadless of the architecture since binutils commit f4d733664aabd7bd78c82895e030ec9779a92809 (2002). The configure check added in commit fdde83499a05 (2001) has long been unneeded. We can therefore treat HAVE_Z_COMBRELOC as always 1 and delete dead code paths in dl-machine.h files (many were copied from commit a711b01d34ca and ee0cb67ec238). Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Remove prelink supportAdhemerval Zanella2022-02-101-27/+21
| | | | | | | | | | | | | Prelinked binaries and libraries still work, the dynamic tags DT_GNU_PRELINKED, DT_GNU_LIBLIST, DT_GNU_CONFLICT just ignored (meaning the process is reallocated as default). The loader environment variable TRACE_PRELINKING is also removed, since it used solely on prelink. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* Update copyright dates with scripts/update-copyrightsPaul Eggert2022-01-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
* elf: Fix dynamic-link.h usage on rtld.cAdhemerval Zanella2021-10-141-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 4af6982e4c fix does not fully handle RTLD_BOOTSTRAP usage on rtld.c due two issues: 1. RTLD_BOOTSTRAP is also used on dl-machine.h on various architectures and it changes the semantics of various machine relocation functions. 2. The elf_get_dynamic_info() change was done sideways, previously to 490e6c62aa get-dynamic-info.h was included by the first dynamic-link.h include *without* RTLD_BOOTSTRAP being defined. It means that the code within elf_get_dynamic_info() that uses RTLD_BOOTSTRAP is in fact unused. To fix 1. this patch now includes dynamic-link.h only once with RTLD_BOOTSTRAP defined. The ELF_DYNAMIC_RELOCATE call will now have the relocation fnctions with the expected semantics for the loader. And to fix 2. part of 4af6982e4c is reverted (the check argument elf_get_dynamic_info() is not required) and the RTLD_BOOTSTRAP pieces are removed. To reorganize the includes the static TLS definition is moved to its own header to avoid a circular dependency (it is defined on dynamic-link.h and dl-machine.h requires it at same time other dynamic-link.h definition requires dl-machine.h defitions). Also ELF_MACHINE_NO_REL, ELF_MACHINE_NO_RELA, and ELF_MACHINE_PLT_REL are moved to its own header. Only ancient ABIs need special values (arm, i386, and mips), so a generic one is used as default. The powerpc Elf64_FuncDesc is also moved to its own header, since csu code required its definition (which would require either include elf/ folder or add a full path with elf/). Checked on x86_64, i686, aarch64, armhf, powerpc64, powerpc32, and powerpc64le. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* elf: Fix elf_get_dynamic_info definitionAdhemerval Zanella2021-10-121-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before to 490e6c62aa31a8a ('elf: Avoid nested functions in the loader [BZ #27220]'), elf_get_dynamic_info() was defined twice on rtld.c: on the first dynamic-link.h include and later within _dl_start(). The former definition did not define DONT_USE_BOOTSTRAP_MAP and it is used on setup_vdso() (since it is a global definition), while the former does define DONT_USE_BOOTSTRAP_MAP and it is used on loader self-relocation. With the commit change, the function is now included and defined once instead of defined as a nested function. So rtld.c defines without defining RTLD_BOOTSTRAP and it brokes at least powerpc32. This patch fixes by moving the get-dynamic-info.h include out of dynamic-link.h, which then the caller can corirectly set the expected semantic by defining STATIC_PIE_BOOTSTRAP, RTLD_BOOTSTRAP, and/or RESOLVE_MAP. It also required to enable some asserts only for the loader bootstrap to avoid issues when called from setup_vdso(). As a side note, this is another issues with nested functions: it is not clear from pre-processed output (-E -dD) how the function will be build and its semantic (since nested function will be local and extra C defines may change it). I checked on x86_64-linux-gnu (w/o --enable-static-pie), i686-linux-gnu, powerpc64-linux-gnu, powerpc-linux-gnu-power4, aarch64-linux-gnu, arm-linux-gnu, sparc64-linux-gnu, and s390x-linux-gnu. Reviewed-by: Fangrui Song <maskray@google.com>
* elf: Avoid nested functions in the loader [BZ #27220]Fangrui Song2021-10-071-12/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | dynamic-link.h is included more than once in some elf/ files (rtld.c, dl-conflict.c, dl-reloc.c, dl-reloc-static-pie.c) and uses GCC nested functions. This harms readability and the nested functions usage is the biggest obstacle prevents Clang build (Clang doesn't support GCC nested functions). The key idea for unnesting is to add extra parameters (struct link_map *and struct r_scope_elm *[]) to RESOLVE_MAP, ELF_MACHINE_BEFORE_RTLD_RELOC, ELF_DYNAMIC_RELOCATE, elf_machine_rel[a], elf_machine_lazy_rel, and elf_machine_runtime_setup. (This is inspired by Stan Shebs' ppc64/x86-64 implementation in the google/grte/v5-2.27/master which uses mixed extra parameters and static variables.) Future simplification: * If mips elf_machine_runtime_setup no longer needs RESOLVE_GOTSYM, elf_machine_runtime_setup can drop the `scope` parameter. * If TLSDESC no longer need to be in elf_machine_lazy_rel, elf_machine_lazy_rel can drop the `scope` parameter. Tested on aarch64, i386, x86-64, powerpc64le, powerpc64, powerpc32, sparc64, sparcv9, s390x, s390, hppa, ia64, armhf, alpha, and mips64. In addition, tested build-many-glibcs.py with {arc,csky,microblaze,nios2}-linux-gnu and riscv64-linux-gnu-rv64imafdc-lp64d. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Remove "Contributed by" linesSiddhesh Poyarekar2021-09-031-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | We stopped adding "Contributed by" or similar lines in sources in 2012 in favour of git logs and keeping the Contributors section of the glibc manual up to date. Removing these lines makes the license header a bit more consistent across files and also removes the possibility of error in attribution when license blocks or files are copied across since the contributed-by lines don't actually reflect reality in those cases. Move all "Contributed by" and similar lines (Written by, Test by, etc.) into a new file CONTRIBUTED-BY to retain record of these contributions. These contributors are also mentioned in manual/contrib.texi, so we just maintain this additional record as a courtesy to the earlier developers. The following scripts were used to filter a list of files to edit in place and to clean up the CONTRIBUTED-BY file respectively. These were not added to the glibc sources because they're not expected to be of any use in future given that this is a one time task: https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02 Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* x86_64: Simplify elf_machine_{load_address,dynamic}Fangrui Song2021-08-171-14/+7
| | | | | | | and drop reliance on _GLOBAL_OFFSET_TABLE_[0] being the link-time address of _DYNAMIC. &__ehdr_start is a better way to get the load address. Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* x86_64: Remove lazy tlsdesc relocation related codeSzabolcs Nagy2021-04-151-4/+0
| | | | | _dl_tlsdesc_resolve_rela and _dl_tlsdesc_resolve_hold are only used for lazy tlsdesc relocation processing which is no longer supported.
* x86_64: Avoid lazy relocation of tlsdesc [BZ #27137]Szabolcs Nagy2021-04-151-5/+14
| | | | | | | | | | | | | Lazy tlsdesc relocation is racy because the static tls optimization and tlsdesc management operations are done without holding the dlopen lock. This similar to the commit b7cf203b5c17dd6d9878537d41e0c7cc3d270a67 for aarch64, but it fixes a different race: bug 27137. Another issue is that ld auditing ignores DT_BIND_NOW and thus tries to relocate tlsdesc lazily, but that does not work in a BIND_NOW module due to missing DT_TLSDESC_PLT. Unconditionally relocating tlsdesc at load time fixes this bug 27721 too.
* x86: Check IFUNC definition in unrelocated executable [BZ #20019]H.J. Lu2021-01-041-5/+11
| | | | | | Calling an IFUNC function defined in unrelocated executable also leads to segfault. Issue a fatal error message when calling IFUNC function defined in the unrelocated executable from a shared library.
* Update copyright dates with scripts/update-copyrightsPaul Eggert2021-01-021-1/+1
| | | | | | | | | | | | | | | | I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
* x86: Initialize CPU info via IFUNC relocation [BZ 26203]H.J. Lu2020-10-161-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | X86 CPU features in ld.so are initialized by init_cpu_features, which is invoked by DL_PLATFORM_INIT from _dl_sysdep_start. But when ld.so is loaded by static executable, DL_PLATFORM_INIT is never called. Also x86 cache info in libc.o and libc.a is initialized by a constructor which may be called too late. Since some fields in _rtld_global_ro in ld.so are initialized by dynamic relocation, we can also initialize x86 CPU features in _rtld_global_ro in ld.so and cache info in libc.so by initializing dummy function pointers in ld.so and libc.so via IFUNC relocation. Key points: 1. IFUNC is always supported, independent of --enable-multi-arch or --disable-multi-arch. Linker generates IFUNC relocations from input IFUNC objects and ld.so performs IFUNC relocations. 2. There are no IFUNC dependencies in ld.so before dynamic relocation have been performed, 3. The x86 CPU features in ld.so is initialized by DL_PLATFORM_INIT in dynamic executable and by IFUNC relocation in dlopen in static executable. 4. The x86 cache info in libc.o is initialized by IFUNC relocation. 5. In libc.a, both x86 CPU features and cache info are initialized from ARCH_INIT_CPU_FEATURES, not by IFUNC relocation, before __libc_early_init is called. Note: _dl_x86_init_cpu_features can be called more than once from DL_PLATFORM_INIT and during relocation in ld.so.
* x86: Support usable check for all CPU featuresH.J. Lu2020-07-131-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support usable check for all CPU features with the following changes: 1. Change struct cpu_features to struct cpuid_features { struct cpuid_registers cpuid; struct cpuid_registers usable; }; struct cpu_features { struct cpu_features_basic basic; struct cpuid_features features[COMMON_CPUID_INDEX_MAX]; unsigned int preferred[PREFERRED_FEATURE_INDEX_MAX]; ... }; so that there is a usable bit for each cpuid bit. 2. After the cpuid bits have been initialized, copy the known bits to the usable bits. EAX/EBX from INDEX_1 and EAX from INDEX_7 aren't used for CPU feature detection. 3. Clear the usable bits which require OS support. 4. If the feature is supported by OS, copy its cpuid bit to its usable bit. 5. Replace HAS_CPU_FEATURE and CPU_FEATURES_CPU_P with CPU_FEATURE_USABLE and CPU_FEATURE_USABLE_P to check if a feature is usable. 6. Add DEPR_FPU_CS_DS for INDEX_7_EBX_13. 7. Unset MPX feature since it has been deprecated. The results are 1. If the feature is known and doesn't requre OS support, its usable bit is copied from the cpuid bit. 2. Otherwise, its usable bit is copied from the cpuid bit only if the feature is known to supported by OS. 3. CPU_FEATURE_USABLE/CPU_FEATURE_USABLE_P are used to check if the feature can be used. 4. HAS_CPU_FEATURE/CPU_FEATURE_CPU_P are used to check if CPU supports the feature.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2020-01-011-1/+1
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* elf: Do not run IFUNC resolvers for LD_DEBUG=unused [BZ #24214]Florian Weimer2019-12-021-1/+2
| | | | | | | | | This commit adds missing skip_ifunc checks to aarch64, arm, i386, sparc, and x86_64. A new test case ensures that IRELATIVE IFUNC resolvers do not run in various diagnostic modes of the dynamic loader. Reviewed-By: Szabolcs Nagy <szabolcs.nagy@arm.com>
* Prefer https to http for gnu.org and fsf.org URLsPaul Eggert2019-09-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
* Add fall-through comments.Joseph Myers2019-02-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds fall-through comments in some cases where -Wextra produces implicit-fallthrough warnings. The patch is non-exhaustive. Apart from architecture-specific code for non-x86_64 architectures, it does not change sunrpc/xdr.c (legacy code, probably should have such changes, but left to be dealt with separately), or places that already had comments about the fall-through but not matching the form expected by -Wimplicit-fallthrough=3 (the default level with -Wextra; my inclination is to adjust those comments to match rather than downgrading to -Wimplicit-fallthrough=1 to allow any comment), or one place where I thought the implicit fallthrough was not correct and so should be handled separately as a bug fix. I think the key thing to consider in review of this patch is whether the fall-through is indeed intended and correct in each place where such a comment is added. Tested for x86_64. * elf/dl-exception.c (_dl_exception_create_format): Add fall-through comments. * elf/ldconfig.c (parse_conf_include): Likewise. * elf/rtld.c (print_statistics): Likewise. * locale/programs/charmap.c (parse_charmap): Likewise. * misc/mntent_r.c (__getmntent_r): Likewise. * posix/wordexp.c (parse_arith): Likewise. (parse_backtick): Likewise. * resolv/ns_ttl.c (ns_parse_ttl): Likewise. * sysdeps/x86/cpu-features.c (init_cpu_features): Likewise. * sysdeps/x86_64/dl-machine.h (elf_machine_rela): Likewise.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2019-01-011-1/+1
| | | | | | | * All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
* elf: Unify symbol address run-time calculation [BZ #19818]Maciej W. Rozycki2018-04-041-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Wrap symbol address run-time calculation into a macro and use it throughout, replacing inline calculations. There are a couple of variants, most of them different in a functionally insignificant way. Most calculations are right following RESOLVE_MAP, at which point either the map or the symbol returned can be checked for validity as the macro sets either both or neither. In some places both the symbol and the map has to be checked however. My initial implementation therefore always checked both, however that resulted in code larger by as much as 0.3%, as many places know from elsewhere that no check is needed. I have decided the size growth was unacceptable. Having looked closer I realized that it's the map that is the culprit. Therefore I have modified LOOKUP_VALUE_ADDRESS to accept an additional boolean argument telling it to access the map without checking it for validity. This in turn has brought quite nice results, with new code actually being smaller for i686, and MIPS o32, n32 and little-endian n64 targets, unchanged in size for x86-64 and, unusually, marginally larger for big-endian MIPS n64, as follows: i686: text data bss dec hex filename 152255 4052 192 156499 26353 ld-2.27.9000-base.so 152159 4052 192 156403 262f3 ld-2.27.9000-elf-symbol-value.so MIPS/o32/el: text data bss dec hex filename 142906 4396 260 147562 2406a ld-2.27.9000-base.so 142890 4396 260 147546 2405a ld-2.27.9000-elf-symbol-value.so MIPS/n32/el: text data bss dec hex filename 142267 4404 260 146931 23df3 ld-2.27.9000-base.so 142171 4404 260 146835 23d93 ld-2.27.9000-elf-symbol-value.so MIPS/n64/el: text data bss dec hex filename 149835 7376 408 157619 267b3 ld-2.27.9000-base.so 149787 7376 408 157571 26783 ld-2.27.9000-elf-symbol-value.so MIPS/o32/eb: text data bss dec hex filename 142870 4396 260 147526 24046 ld-2.27.9000-base.so 142854 4396 260 147510 24036 ld-2.27.9000-elf-symbol-value.so MIPS/n32/eb: text data bss dec hex filename 142019 4404 260 146683 23cfb ld-2.27.9000-base.so 141923 4404 260 146587 23c9b ld-2.27.9000-elf-symbol-value.so MIPS/n64/eb: text data bss dec hex filename 149763 7376 408 157547 2676b ld-2.27.9000-base.so 149779 7376 408 157563 2677b ld-2.27.9000-elf-symbol-value.so x86-64: text data bss dec hex filename 148462 6452 400 155314 25eb2 ld-2.27.9000-base.so 148462 6452 400 155314 25eb2 ld-2.27.9000-elf-symbol-value.so [BZ #19818] * sysdeps/generic/ldsodefs.h (LOOKUP_VALUE_ADDRESS): Add `set' parameter. (SYMBOL_ADDRESS): New macro. [!ELF_FUNCTION_PTR_IS_SPECIAL] (DL_SYMBOL_ADDRESS): Use SYMBOL_ADDRESS for symbol address calculation. * elf/dl-runtime.c (_dl_fixup): Likewise. (_dl_profile_fixup): Likewise. * elf/dl-symaddr.c (_dl_symbol_address): Likewise. * elf/rtld.c (dl_main): Likewise. * sysdeps/aarch64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/alpha/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/arm/dl-machine.h (elf_machine_rel): Likewise. (elf_machine_rela): Likewise. * sysdeps/hppa/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/hppa/dl-symaddr.c (_dl_symbol_address): Likewise. * sysdeps/i386/dl-machine.h (elf_machine_rel): Likewise. (elf_machine_rela): Likewise. * sysdeps/ia64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/m68k/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/microblaze/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/mips/dl-machine.h (ELF_MACHINE_BEFORE_RTLD_RELOC): Likewise. (elf_machine_reloc): Likewise. (elf_machine_got_rel): Likewise. * sysdeps/mips/dl-trampoline.c (__dl_runtime_resolve): Likewise. * sysdeps/nios2/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/riscv/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sh/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/tile/dl-machine.h (elf_machine_rela): Likewise. * sysdeps/x86_64/dl-machine.h (elf_machine_rela): Likewise. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* x86-64: Use __glibc_likely/__glibc_likely in dl-machine.hH.J. Lu2018-02-051-7/+7
| | | | | | | | | | | | | | | | | | | | The differences in elf/dl-reloc.os are --- before 2018-02-05 03:52:32.803125207 -0800 +++ after 2018-02-05 03:52:14.913711879 -0800 @@ -1129,7 +1129,7 @@ _dl_relocate_object: leaq __PRETTY_FUNCTION__.9767(%rip), %rcx leaq .LC11(%rip), %rsi leaq .LC12(%rip), %rdi - movl $540, %edx + movl $539, %edx call __GI___assert_fail .p2align 4,,10 .p2align 3 * sysdeps/x86_64/dl-machine.h (elf_machine_rela): Replace __builtin_expect with __glibc_likely and __glibc_likely. (elf_machine_lazy_rel): Likewise.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2018-01-011-1/+1
| | | | | | | * All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
* x86-64: Use fxsave/xsave/xsavec in _dl_runtime_resolve [BZ #21265]H.J. Lu2017-10-201-28/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In _dl_runtime_resolve, use fxsave/xsave/xsavec to preserve all vector, mask and bound registers. It simplifies _dl_runtime_resolve and supports different calling conventions. ld.so code size is reduced by more than 1 KB. However, use fxsave/xsave/xsavec takes a little bit more cycles than saving and restoring vector and bound registers individually. Latency for _dl_runtime_resolve to lookup the function, foo, from one shared library plus libc.so: Before After Change Westmere (SSE)/fxsave 345 866 151% IvyBridge (AVX)/xsave 420 643 53% Haswell (AVX)/xsave 713 1252 75% Skylake (AVX+MPX)/xsavec 559 719 28% Skylake (AVX512+MPX)/xsavec 145 272 87% Ryzen (AVX)/xsavec 280 553 97% This is the worst case where portion of time spent for saving and restoring registers is bigger than majority of cases. With smaller _dl_runtime_resolve code size, overall performance impact is negligible. On IvyBridge, differences in build and test time of binutils with lazy binding GCC and binutils are noises. On Westmere, differences in bootstrap and "makc check" time of GCC 7 with lazy binding GCC and binutils are also noises. [BZ #21265] * sysdeps/x86/cpu-features-offsets.sym (XSAVE_STATE_SIZE_OFFSET): New. * sysdeps/x86/cpu-features.c: Include <libc-pointer-arith.h>. (get_common_indeces): Set xsave_state_size, xsave_state_full_size and bit_arch_XSAVEC_Usable if needed. (init_cpu_features): Remove bit_arch_Use_dl_runtime_resolve_slow and bit_arch_Use_dl_runtime_resolve_opt. * sysdeps/x86/cpu-features.h (bit_arch_Use_dl_runtime_resolve_opt): Removed. (bit_arch_Use_dl_runtime_resolve_slow): Likewise. (bit_arch_Prefer_No_AVX512): Updated. (bit_arch_MathVec_Prefer_No_AVX512): Likewise. (bit_arch_XSAVEC_Usable): New. (STATE_SAVE_OFFSET): Likewise. (STATE_SAVE_MASK): Likewise. [__ASSEMBLER__]: Include <cpu-features-offsets.h>. (cpu_features): Add xsave_state_size and xsave_state_full_size. (index_arch_Use_dl_runtime_resolve_opt): Removed. (index_arch_Use_dl_runtime_resolve_slow): Likewise. (index_arch_XSAVEC_Usable): New. * sysdeps/x86/cpu-tunables.c (TUNABLE_CALLBACK (set_hwcaps)): Support XSAVEC_Usable. Remove Use_dl_runtime_resolve_slow. * sysdeps/x86_64/Makefile (tst-x86_64-1-ENV): New if tunables is enabled. * sysdeps/x86_64/dl-machine.h (elf_machine_runtime_setup): Replace _dl_runtime_resolve_sse, _dl_runtime_resolve_avx, _dl_runtime_resolve_avx_slow, _dl_runtime_resolve_avx_opt, _dl_runtime_resolve_avx512 and _dl_runtime_resolve_avx512_opt with _dl_runtime_resolve_fxsave, _dl_runtime_resolve_xsave and _dl_runtime_resolve_xsavec. * sysdeps/x86_64/dl-trampoline.S (DL_RUNTIME_UNALIGNED_VEC_SIZE): Removed. (DL_RUNTIME_RESOLVE_REALIGN_STACK): Check STATE_SAVE_ALIGNMENT instead of VEC_SIZE. (REGISTER_SAVE_BND0): Removed. (REGISTER_SAVE_BND1): Likewise. (REGISTER_SAVE_BND3): Likewise. (REGISTER_SAVE_RAX): Always defined to 0. (VMOV): Removed. (_dl_runtime_resolve_avx): Likewise. (_dl_runtime_resolve_avx_slow): Likewise. (_dl_runtime_resolve_avx_opt): Likewise. (_dl_runtime_resolve_avx512): Likewise. (_dl_runtime_resolve_avx512_opt): Likewise. (_dl_runtime_resolve_sse): Likewise. (_dl_runtime_resolve_sse_vex): Likewise. (USE_FXSAVE): New. (_dl_runtime_resolve_fxsave): Likewise. (USE_XSAVE): Likewise. (_dl_runtime_resolve_xsave): Likewise. (USE_XSAVEC): Likewise. (_dl_runtime_resolve_xsavec): Likewise. * sysdeps/x86_64/dl-trampoline.h (_dl_runtime_resolve_avx512): Removed. (_dl_runtime_resolve_avx512_opt): Likewise. (_dl_runtime_resolve_avx): Likewise. (_dl_runtime_resolve_avx_opt): Likewise. (_dl_runtime_resolve_sse): Likewise. (_dl_runtime_resolve_sse_vex): Likewise. (_dl_runtime_resolve_fxsave): New. (_dl_runtime_resolve_xsave): Likewise. (_dl_runtime_resolve_xsavec): Likewise.
* Revert x86: Allow undefined _DYNAMIC in static executableH.J. Lu2017-10-031-9/+2
| | | | | | | | | | | | This code is used in non-PIE static executable and static PIE. It checks if _DYNAMIC is undefined before using it to compute load address. But not all targets can convert access _DYNAMIC via GOT, which needs dynamic relocation, to PC-relative at link-time. * sysdeps/i386/dl-machine.h (elf_machine_load_address): Don't allow undefined _DYNAMIC in PIE libc.a. * sysdeps/x86_64/dl-machine.h (elf_machine_load_address): Likewse.
* x86: Allow undefined _DYNAMIC in static executableH.J. Lu2017-09-281-2/+9
| | | | | | | | | | | | When --enable-static-pie is used to build static PIE, _DYNAMIC is used to compute the load address of static PIE. But _DYNAMIC is undefined when creating static executable. This patch makes _DYNAMIC weak in PIE libc.a so that it can be undefined. * sysdeps/i386/dl-machine.h (elf_machine_load_address): Allow undefined _DYNAMIC in PIE libc.a. * sysdeps/x86_64/dl-machine.h (elf_machine_load_address): Likewse.
* PowerPC64 ELFv2 PPC64_OPT_LOCALENTRYAlan Modra2017-06-141-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ELFv2 functions with localentry:0 are those with a single entry point, ie. global entry == local entry, that have no requirement on r2 or r12 and guarantee r2 is unchanged on return. Such an external function can be called via the PLT without saving r2 or restoring it on return, avoiding a common load-hit-store for small functions. This patch implements the ld.so changes necessary for this optimization. ld.so needs to check that an optimized plt call sequence is in fact calling a function implemented with localentry:0, end emit a fatal error otherwise. The elf/testobj6.c change is to stop "error while loading shared libraries: expected localentry:0 `preload'" when running elf/preloadtest, which we'd get otherwise. * elf/elf.h (PPC64_OPT_LOCALENTRY): Define. * sysdeps/alpha/dl-machine.h (elf_machine_fixup_plt): Add refsym and sym parameters. Adjust callers. * sysdeps/aarch64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/arm/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/generic/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/hppa/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/i386/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/ia64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/m68k/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/microblaze/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/mips/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/nios2/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/sh/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/tile/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/x86_64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/powerpc/powerpc64/dl-machine.c (_dl_error_localentry): New. (_dl_reloc_overflow): Increase buffser size. Formatting. * sysdeps/powerpc/powerpc64/dl-machine.h (ppc64_local_entry_offset): Delete reloc param, add refsym and sym. Check optimized plt call stubs for localentry:0 functions. Adjust callers. (elf_machine_fixup_plt, elf_machine_plt_conflict): Add refsym and sym parameters. Adjust callers. (_dl_reloc_overflow): Move attribute. (_dl_error_localentry): Declare. * elf/dl-runtime.c (_dl_fixup): Save original sym. Pass refsym and sym to elf_machine_fixup_plt. * elf/testobj6.c (preload): Call printf.
* x86: Set dl_platform and dl_hwcap from CPU features [BZ #21391]H.J. Lu2017-05-031-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | dl_platform and dl_hwcap are set from AT_PLATFORM and AT_HWCAP very early during startup. They are used by dynamic linker to determine platform and build an array of hardware capability names, which are added to search path when loading shared object. dl_platform and dl_hwcap are unused on x86-64. On i386, i386, i486, i586 and i686 platforms were supported and only SSE2 capability was used. On x86, usage of AT_PLATFORM and AT_HWCAP to determine platform and processor capabilities is obsolete since all information is available in dl_x86_cpu_features. This patch sets dl_platform and dl_hwcap from dl_x86_cpu_features in dynamic linker. On i386, the available plaforms are changed to i586 and i686 since i386 has been deprecated. On x86-64, the available plaforms are haswell, which is for Haswell class processors with BMI1, BMI2, LZCNT, MOVBE, POPCNT, AVX2 and FMA, and xeon_phi, which is for Xeon Phi class processors with AVX512F, AVX512CD, AVX512ER and AVX512PF. A capability, avx512_1, is also added to x86-64 for AVX512 ISAs: AVX512F, AVX512CD, AVX512BW, AVX512DQ and AVX512VL. [BZ #21391] * sysdeps/i386/dl-machine.h (dl_platform_init) [IS_IN (rtld)]: Only call init_cpu_features. [!IS_IN (rtld)]: Only set GLRO(dl_platform) to NULL if needed. * sysdeps/x86_64/dl-machine.h (dl_platform_init): Likewise. * sysdeps/i386/dl-procinfo.h: Removed. * sysdeps/unix/sysv/linux/i386/dl-procinfo.h: Don't include <sysdeps/i386/dl-procinfo.h> nor <ldsodefs.h>. Include <sysdeps/x86/dl-procinfo.h>. (_dl_procinfo): Replace _DL_HWCAP_COUNT with 32. * sysdeps/unix/sysv/linux/x86_64/dl-procinfo.h [!IS_IN (ldconfig)]: Include <sysdeps/x86/dl-procinfo.h> instead of <sysdeps/generic/dl-procinfo.h>. * sysdeps/x86/cpu-features.c: Include <dl-hwcap.h>. (init_cpu_features): Set dl_platform, dl_hwcap and dl_hwcap_mask. * sysdeps/x86/cpu-features.h (bit_cpu_LZCNT): New. (bit_cpu_MOVBE): Likewise. (bit_cpu_BMI1): Likewise. (bit_cpu_BMI2): Likewise. (index_cpu_BMI1): Likewise. (index_cpu_BMI2): Likewise. (index_cpu_LZCNT): Likewise. (index_cpu_MOVBE): Likewise. (index_cpu_POPCNT): Likewise. (reg_BMI1): Likewise. (reg_BMI2): Likewise. (reg_LZCNT): Likewise. (reg_MOVBE): Likewise. (reg_POPCNT): Likewise. * sysdeps/x86/dl-hwcap.h: New file. * sysdeps/x86/dl-procinfo.h: Likewise. * sysdeps/x86/dl-procinfo.c (_dl_x86_hwcap_flags): New. (_dl_x86_platforms): Likewise.
* Allow IFUNC relocation against unrelocated shared libraryH.J. Lu2017-02-021-1/+1
| | | | | | | | | | | | | | | | | IFUNC relocation against definition in unrelocated shared library will lead to segfault when the IFUNC function is called. This patch allows such IFUNC relocations with a warning. This isn't a real fix for https://sourceware.org/bugzilla/show_bug.cgi?id=21041 It simply allows the program to load. The program will segfault when longjmp is called. * sysdeps/i386/dl-machine.h (elf_machine_rel): Replace _dl_fatal_printf with _dl_error_printf for IFUNC relocation against unrelocated shared library. * sysdeps/x86_64/dl-machine.h (elf_machine_rela): Likewise.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2017-01-011-1/+1
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* Check IFUNC definition in unrelocated shared library [BZ #20019]H.J. Lu2016-10-281-1/+17
| | | | | | | | | | | | Calling an IFUNC function defined in unrelocated shared library may lead to segfault. This patch issues an error message to request relinking the shared library if it references IFUNC function defined in the unrelocated shared library. [BZ #20019] * sysdeps/i386/dl-machine.h (elf_machine_rel): Check IFUNC definition in unrelocated shared library. * sysdeps/x86_64/dl-machine.h (elf_machine_rela): Likewise.
* X86-64: Add _dl_runtime_resolve_avx[512]_{opt|slow} [BZ #20508]H.J. Lu2016-09-061-2/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is transition penalty when SSE instructions are mixed with 256-bit AVX or 512-bit AVX512 load instructions. Since _dl_runtime_resolve_avx and _dl_runtime_profile_avx512 save/restore 256-bit YMM/512-bit ZMM registers, there is transition penalty when SSE instructions are used with lazy binding on AVX and AVX512 processors. To avoid SSE transition penalty, if only the lower 128 bits of the first 8 vector registers are non-zero, we can preserve %xmm0 - %xmm7 registers with the zero upper bits. For AVX and AVX512 processors which support XGETBV with ECX == 1, we can use XGETBV with ECX == 1 to check if the upper 128 bits of YMM registers or the upper 256 bits of ZMM registers are zero. We can restore only the non-zero portion of vector registers with AVX/AVX512 load instructions which will zero-extend upper bits of vector registers. This patch adds _dl_runtime_resolve_sse_vex which saves and restores XMM registers with 128-bit AVX store/load instructions. It is used to preserve YMM/ZMM registers when only the lower 128 bits are non-zero. _dl_runtime_resolve_avx_opt and _dl_runtime_resolve_avx512_opt are added and used on AVX/AVX512 processors supporting XGETBV with ECX == 1 so that we store and load only the non-zero portion of vector registers. This avoids SSE transition penalty caused by _dl_runtime_resolve_avx and _dl_runtime_profile_avx512 when only the lower 128 bits of vector registers are used. _dl_runtime_resolve_avx_slow is added and used for AVX processors which don't support XGETBV with ECX == 1. Since there is no SSE transition penalty on AVX512 processors which don't support XGETBV with ECX == 1, _dl_runtime_resolve_avx512_slow isn't provided. [BZ #20495] [BZ #20508] * sysdeps/x86/cpu-features.c (init_cpu_features): For Intel processors, set Use_dl_runtime_resolve_slow and set Use_dl_runtime_resolve_opt if XGETBV suports ECX == 1. * sysdeps/x86/cpu-features.h (bit_arch_Use_dl_runtime_resolve_opt): New. (bit_arch_Use_dl_runtime_resolve_slow): Likewise. (index_arch_Use_dl_runtime_resolve_opt): Likewise. (index_arch_Use_dl_runtime_resolve_slow): Likewise. * sysdeps/x86_64/dl-machine.h (elf_machine_runtime_setup): Use _dl_runtime_resolve_avx512_opt and _dl_runtime_resolve_avx_opt if Use_dl_runtime_resolve_opt is set. Use _dl_runtime_resolve_slow if Use_dl_runtime_resolve_slow is set. * sysdeps/x86_64/dl-trampoline.S: Include <cpu-features.h>. (_dl_runtime_resolve_opt): New. Defined for AVX and AVX512. (_dl_runtime_resolve): Add one for _dl_runtime_resolve_sse_vex. * sysdeps/x86_64/dl-trampoline.h (_dl_runtime_resolve_avx_slow): New. (_dl_runtime_resolve_opt): Likewise. (_dl_runtime_profile): Define only if _dl_runtime_profile is defined.
* Call init_cpu_features only if SHARED is definedH.J. Lu2016-05-131-0/+4
| | | | | | | | | | In static executable, since init_cpu_features is called early from __libc_start_main, there is no need to call it again in dl_platform_init. [BZ #20072] * sysdeps/i386/dl-machine.h (dl_platform_init): Call init_cpu_features only if SHARED is defined. * sysdeps/x86_64/dl-machine.h (dl_platform_init): Likewise.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2016-01-041-1/+1
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* Save and restore vector registers in x86-64 ld.soH.J. Lu2015-08-251-6/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds SSE, AVX and AVX512 versions of _dl_runtime_resolve and _dl_runtime_profile, which save and restore the first 8 vector registers used for parameter passing. elf_machine_runtime_setup selects the proper _dl_runtime_resolve or _dl_runtime_profile based on _dl_x86_cpu_features. It avoids race condition caused by FOREIGN_CALL macros, which are only used for x86-64. Performance impact of saving and restoring 8 vector registers are negligible on Nehalem, Sandy Bridge, Ivy Bridge and Haswell when ld.so is optimized with SSE2. [BZ #15128] * sysdeps/x86_64/Makefile [$(subdir) == elf] (tests): Add ifuncmain8. (modules-names): Add ifuncmod8. ($(objpfx)ifuncmain8): New rule. * sysdeps/x86_64/dl-machine.h: Include <dl-procinfo.h> and <cpuid.h>. (elf_machine_runtime_setup): Use _dl_runtime_resolve_sse, _dl_runtime_resolve_avx, or _dl_runtime_resolve_avx512, _dl_runtime_profile_sse, _dl_runtime_profile_avx, or _dl_runtime_profile_avx512, based on HAS_ARCH_FEATURE. * sysdeps/x86_64/dl-trampoline.S: Rewrite. * sysdeps/x86_64/dl-trampoline.h: Likewise. * sysdeps/x86_64/ifuncmain8.c: New file. * sysdeps/x86_64/ifuncmod8.c: Likewise. * sysdeps/x86_64/nptl/tcb-offsets.sym (RTLD_SAVESPACE_SSE): Removed. * sysdeps/x86_64/nptl/tls.h (__128bits): Removed. (tcbhead_t): Change rtld_must_xmm_save to __glibc_unused1. Change rtld_savespace_sse to __glibc_unused2. (RTLD_CHECK_FOREIGN_CALL): Removed. (RTLD_ENABLE_FOREIGN_CALL): Likewise. (RTLD_PREPARE_FOREIGN_CALL): Likewise. (RTLD_FINALIZE_FOREIGN_CALL): Likewise.
* Add _dl_x86_cpu_features to rtld_globalH.J. Lu2015-08-131-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds _dl_x86_cpu_features to rtld_global in x86 ld.so and initializes it early before __libc_start_main is called so that cpu_features is always available when it is used and we can avoid calling __init_cpu_features in IFUNC selectors. * sysdeps/i386/dl-machine.h: Include <cpu-features.c>. (dl_platform_init): Call init_cpu_features. * sysdeps/i386/dl-procinfo.c (_dl_x86_cpu_features): New. * sysdeps/i386/i686/cacheinfo.c (DISABLE_PREFERRED_MEMORY_INSTRUCTION): Removed. * sysdeps/i386/i686/multiarch/Makefile (aux): Remove init-arch. * sysdeps/i386/i686/multiarch/Versions: Removed. * sysdeps/i386/i686/multiarch/ifunc-defines.sym (KIND_OFFSET): Removed. * sysdeps/i386/ldsodefs.h: Include <cpu-features.h>. * sysdeps/unix/sysv/linux/x86/Makefile (libpthread-sysdep_routines): Remove init-arch. * sysdeps/unix/sysv/linux/x86_64/dl-procinfo.c: Include <sysdeps/x86_64/dl-procinfo.c> instead of sysdeps/generic/dl-procinfo.c>. * sysdeps/x86/Makefile [$(subdir) == csu] (gen-as-const-headers): Add cpu-features-offsets.sym and rtld-global-offsets.sym. [$(subdir) == elf] (sysdep-dl-routines): Add dl-get-cpu-features. [$(subdir) == elf] (tests): Add tst-get-cpu-features. [$(subdir) == elf] (tests-static): Add tst-get-cpu-features-static. * sysdeps/x86/Versions: New file. * sysdeps/x86/cpu-features-offsets.sym: Likewise. * sysdeps/x86/cpu-features.c: Likewise. * sysdeps/x86/cpu-features.h: Likewise. * sysdeps/x86/dl-get-cpu-features.c: Likewise. * sysdeps/x86/libc-start.c: Likewise. * sysdeps/x86/rtld-global-offsets.sym: Likewise. * sysdeps/x86/tst-get-cpu-features-static.c: Likewise. * sysdeps/x86/tst-get-cpu-features.c: Likewise. * sysdeps/x86_64/dl-procinfo.c: Likewise. * sysdeps/x86_64/cacheinfo.c (__cpuid_count): Removed. Assume USE_MULTIARCH is defined and don't check it. (is_intel): Replace __cpu_features with GLRO(dl_x86_cpu_features). (is_amd): Likewise. (max_cpuid): Likewise. (intel_check_word): Likewise. (__cache_sysconf): Don't call __init_cpu_features. (__x86_preferred_memory_instruction): Removed. (init_cacheinfo): Don't call __init_cpu_features. Replace __cpu_features with GLRO(dl_x86_cpu_features). * sysdeps/x86_64/dl-machine.h: <cpu-features.c>. (dl_platform_init): Call init_cpu_features. * sysdeps/x86_64/ldsodefs.h: Include <cpu-features.h>. * sysdeps/x86_64/multiarch/Makefile (aux): Remove init-arch. * sysdeps/x86_64/multiarch/Versions: Removed. * sysdeps/x86_64/multiarch/cacheinfo.c: Likewise. * sysdeps/x86_64/multiarch/init-arch.c: Likewise. * sysdeps/x86_64/multiarch/ifunc-defines.sym (KIND_OFFSET): Removed. * sysdeps/x86_64/multiarch/init-arch.h: Rewrite.