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2019-10-30Make __syscall_error return long, as expected by syscall() callersCarlos Santos
The return type of syscall() is long so __syscall_error, which is jumped to by syscall handlers to stash an error number into errno, must return long too otherwhise it returs 4294967295L instead of -1L. For example, syscall for x86_64 is defined in libc/sysdeps/linux/x86_64/syscall.S as syscall: movq %rdi, %rax /* Syscall number -> rax. */ movq %rsi, %rdi /* shift arg1 - arg5. */ movq %rdx, %rsi movq %rcx, %rdx movq %r8, %r10 movq %r9, %r8 movq 8(%rsp),%r9 /* arg6 is on the stack. */ syscall /* Do the system call. */ cmpq $-4095, %rax /* Check %rax for error. */ jae __syscall_error /* Branch forward if it failed. */ ret /* Return to caller. */ In libc/sysdeps/linux/x86_64/__syscall_error.c, __syscall_error is defined as int __syscall_error(void) attribute_hidden; int __syscall_error(void) { register int err_no __asm__ ("%rcx"); __asm__ ("mov %rax, %rcx\n\t" "neg %rcx"); __set_errno(err_no); return -1; } So __syscall_error returns -1 as a 32-bit int in a 64-bit register, %rax (0x00000000ffffffff, whose decimal value is decimal 4294967295) and a test like this always returns false: if (syscall(number, ...) == -1) foo(); Fix the error by making __syscall_error return a long, like syscall(). The problem can be circumvented by the caller by coercing the returned value to int before comparing it to -1: if ((int) syscall(number, ...) == -1) foo(); The same problem probably occurs on other 64-bit systems but so far only x86_64 was tested, so this change must be considered experimental. Signed-off-by: Carlos Santos <unixmania@gmail.com>
2017-09-14arc: Ensure that debugger can recognize sigrestorerAnton Kolesov
An issue has been found with current implementation of signal restorer function in uClibc and how GDB handles it. When debugger information is not present, everything worked fine, because GDB would use a built-in logic to determine if function is a signal restorer. However when debugging information is present, debugger would rely solely on it and wouldn't use ARC-specific functions to detect signal handler frames. Because debug information for signal restorer is generated completely by the compiler, it lacks a marker, that identifies this as a signal frame that requires special handling. While it is possible to insert that marker via inline assembly, that still doesn't solve the whole problem, because some other expectations are not met by the debug information - there is no "nop" in front of the function, needed to fool debugger into thinking that this was a function call, and references to previous frame information need to be described manually. The simplest way to fix the problem is just to make sure that signal restorer function will not have any debug function at all, which can be done by writing it in assembly. Alternative, more complex, solution, where debug information for signal frame is manually defined can be found in glibc/sysdeps/unix/sysv/linux/x86_64/sigaction.c [1]. [1] https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/x86_64/sigaction.c;hb=HEAD Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
2017-06-08fcntl.h: fixup namespace for O_DIRECTORY/O_NOFOLLOW/O_CLOEXECWaldemar Brodkorb
Sync with GNU C library. Found while trying to compile linux-rdma to uClibc-ng. Reported-by: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
2017-01-28remove PID cachingWaldemar Brodkorb
Follow GNU C Library from c579f48edba88380635ab98cb612030e3ed8691e and remove the PID caching. These simplifies the architecture specific assembly code. The run of the test suite found no regressions, it even solves some of the test failures for x86/x86_64/sparc. Reviewed-by: Max Filippov <jcmvbkbc@gmail.com> Reviewed-by: Vineet Gupta <Vineet.Gupta1@synopsys.com> Acked-by: Matthew Fortune <Matthew.Fortune@imgtec.com> Acked-by: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
2016-11-13NPTL/ARC: provide a kernel assisted atomic cmpxchgVineet Gupta
For hardware configurations lacking LLOCK/SCOND (say ARC750), use a syscall to atomically do the cmpxchg. This is costly and painful, but really the only way out. Note that kenrel only guarantees this to work in a UP configuraion Reported-by: Avinash Patil <avinashp@quantenna.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-11-13NPTL/ARC: implement __arch_exchange_32_acq using native EXVineet Gupta
ARC EX instruction maps directly to this primitive, thus helps elide the llock/scond based retry loop where possible. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-10-19ARC: update .note.ABI-tag for ABIv4Vineet Gupta
Cc: Anton Kolesov <akolesov@synopsys.com> Cc: linux-snps-arc@lists.infradead.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-08-17ARC: Support syscall ABI v4Vineet Gupta
The syscall ABI includes the gcc functional calling ABI since a syscall implies userland caller and kernel callee. The current gcc ABI (v3) for ARCv2 ISA required 64-bit data be passed in even-odd register pairs, (potentially punching reg holes when passing such values as args). This was partly driven by the fact that the double-word LDD/STD instructions in ARCv2 expect the register alignment and thus gcc forcing this avoids extra MOV at the cost of a few unused register (which we have plenty anyways). This however was rejected as part of upstreaming gcc port to HS. So the new ABI v4 doesn't enforce the even-odd reg restriction. Do note that for ARCompact ISA builds v3 and v4 are practically the same in terms of gcc code generation. This change is dormant for now (gcc 4.8.x based tools) and will only kick in with switch to gcc 6.x based tools. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-08-01arc: crt1: Fix to PIECupertino Miranda
crt1.S needed to use a got relative reference. Libraries like pthreads define a _init and unless it is GOT, the linker will fail because it will try to create a dynamic reloc on .text section, more precisely on __start. Signed-off-by: Cupertino Miranda <cmiranda@synopsys.com> Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Cc: Vlad Zakharov <vzakhar@synopsys.com> Cc: Vineet Gupta <vgupta@synopsys.com>
2016-07-31arc: clone: Simplify CLONE_THREAD detectionAlexey Brodkin
This change was inspired by similar change in glibc: https://sourceware.org/git/?p=glibc.git;a=commit;h=0cb313f7cb0e418b3d56f3a2ac69790522ab825d Current Linux kernel requires CLONE_VM to be set with CLONE_THREAD otherwise returning -EINVAL, see man clone2. This means we don't need to check for both CLONE_THREAD and CLONE_VM instead we may simplify code a lot and just check 1 bit (CLONE_THREAD). Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Acked-by: Vineet Gupta <vgupta@synopsys.com>
2016-07-31arc: clone: Fix CLONE_THREAD detectionAlexey Brodkin
For thread group case (CLONE_THREAD), the cached PID of new process/thread need not be reset. The old logic to decide that was flawed as it would be true only for exact combination of CLONE_THREAD + _VM, but would fail for CLONE_THREAD + _VM + _xyz. More detailed tear-down of current and new code below. Current implementation is: --------------------->8-------------------- ; r12 contains clone flags mov_s r2, CLONE_THREAD_N_VM; r2 contains bit mask and_s r2, r2, r12 ; r2 contains bit mask AND clone flags ; but r12 still contains the same flags brne r2, r12, .Lgo_thread ; here we compare modified mask with ; flags as they were and skip pthread TID/PID ; setup if r2 != r12 which happens all ; the time except clone flags were ; exactly CLONE_THREAD | CLONE_VM --------------------->8-------------------- New implementation is: --------------------->8-------------------- ; r12 contains clone flags mov_s r2, CLONE_THREAD_N_VM; r2 contains bit mask and_s r12, r12, r2 ; r12 contains clone flags AND bit mask ; i.e. we did mask all flags except ; CLONE_THREAD and CLONE_VM breq r2, r12, .Lgo_thread ; here we compare masked flags with ; target mask and if they match we skip ; pthread TID/PID setup --------------------->8-------------------- Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Acked-by: Vineet Gupta <vgupta@synopsys.com>
2016-07-31arc: clone: Recover PID correctlyAlexey Brodkin
Caught by tst-getpid1 test from uClibc's test-suite. It looks like original implementation was not correct. The code in question is supposed to recover PID of the new thread. And by no means that could happen with clone() syscall while getpid() does exactly this. Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Reported-by: Eugeniy Paltsev <paltsev@synopsys.com>
2016-07-31deduplicate jmpbuf-unwind.hWaldemar Brodkorb
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
2016-07-17cleanup PTR_MANGLE/PTR_DEMANGLE supportWaldemar Brodkorb
As this is only implemented for a few architecture and not well tested, just remove it. Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
2016-06-23ARC: Enable shared crt1Vineet Gupta
Currently crt1 takes address of functions (main,_init,_fini) directly which doesn't generate truely position independent code, but zero based values instead. e.g. | __start: | ... | add_s r2,sp,0x4 | mov_s r0, main generates to | 000156ec <__start>: | ... | 156f4: add_s r2,sp,0x4 | 156f6: mov_s r0,0x15f7c | ... | 00015f7c <main>: | 15f7c: push_s blink This works just fine for the normal (non PIE) dynamic executables since they are loaded at address 0. However this is not true for PIE executables. So for Scrt1 we use a true position independent way when taking function addresses. Cc: uclibc@uclibc.org <uclibc@uclibc.org> Cc: devel@uclibc-ng.org <devel@uclibc-ng.org> Cc: Cupertino Miranda <cmiranda@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-06-23ARC: Implement .note.ABI-tag section in crt1.SAnton Kolesov
Linux Standard Base specifies section .note.ABI-tag that can be considered as a marker for ELF files targeted to Linux systems. See https://refspecs.linuxfoundation.org/LSB_1.2.0/gLSB/noteabitag.html This section, for example, is used by the GDB to identify Linux ELFs as compared to baremetal ELFs that do not have this section. Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com> Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
2015-12-07add definitions for O_PATHWaldemar Brodkorb
Only alpha, hppa and sparc need non-default value.
2015-12-05remove __UCLIBC_ASM_GLOBAL_DIRECTIVE__Waldemar Brodkorb
.globl can be used for every architecture so remove the define. Sync with GNU C library.
2015-12-05remove __UCLIBC_HAVE_ASM_GLOBAL_DOT_NAME__Waldemar Brodkorb
It's even no longer required for non-ported ppc64 architecture. Sync with GNU C library. This simplify the macros in include/libc-symbols.h.
2015-10-22NPTL/ARCv2: Implement full memory barrier for NPTLVineet Gupta
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-03-27ARC: don't hard-code ELF_NGREGAlexey Brodkin
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [updated changelog] Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2015-03-27ARC/signal: shield sa_restorer from compiler toggle side-effectsVineet Gupta
when building uClibc with -O0 (DODEBUG build) the default sigrestorer had some extra glue code generated for stack manipulation which was messing up resume from signal path. So annotate the function with -Os so that gcc would only generate the bare min 2 instruction TRAP sequence Reported-and-Debugged-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2015-02-20ARCv2 ISA supportVineet Gupta
This is next gen Instruction Set Architecture from Synopsys and basis for the ARC HS family of processors. http://www.synopsys.com/dw/ipdir.php?ds=arc-hs38-processor&elq_mid=5732&elq_cid=458802 http://www.synopsys.com/IP/ProcessorIP/ARCProcessors/arc-hs/Pages/default.aspx Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2015-02-16ARC: sigaction: inline syscall trapVineet Gupta
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2015-02-16ARC: sigaction: fold default sigrestorer into "C"Vineet Gupta
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2015-02-16ARC: siagction: opencode memcpyVineet Gupta
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2015-02-16ARC: remove stale TRUNCATE64_HAS_4_ARGSVineet Gupta
Not relevant anymore since commit e8cc14e59ed3f66b84e, "libc: rename TRUNCATE64_HAS_4_ARGS to SYSCALL_ALIGN_64BIT" Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2015-02-16ARC: add configuration option for MMU page sizeAlexey Brodkin
ARC CPU may have MMU page size of 4/8(default)/16k. uClibc needs to have page size configured accodring to HW it will be run on. Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2014-08-25fcntl.h: Define F_SETPIPE_SZ and F_GETPIPE_SZKhem Raj
Signed-off-by: Khem Raj <raj.khem@gmail.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2014-08-18ARC/NPTL: clone to set TP if CLONE_SETTLSVineet Gupta
Typically kernel would set the TP register of newly created thread in clone syscall with CLONE_SETTLS. However this implies that: * kernel knows of the exact TP register (which is already different for ARCompact and ARCv2) and is a detail which becomes part of the ABI * kernel also needs to handle the unlikely but possible case of !TLS userspace (e.g. Android libc) case where TP reg is not reserved and thus need not be mucked with (using ELF personality based detection) It is better to confine this detail to userspace runtime and set TP reg right after clone syscall returns. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2014-08-18NPTL: ARC supportVineet Gupta
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2014-07-22ARC: Implement native GDB requirements in procfs.hAnton Kolesov
Native GDB requires elf_fpregset_t to be defined, even if floating point registers are absent. In this case we use empty structure. Additionally we redefined prfpregset_t to use this new type. And there has been an error: it was defined that user_regs_struct has 20 registers, while it has 40. Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2014-07-22ARC: clone: Ensure that @fn returns back to cloneVineet Gupta
This showed up due to longstanding test/unistd/clone failure where post clone, the callback was not exiting and rather falling thru in into main program. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2014-07-22ARC: make sigaction inline with other archesVineet Gupta
Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2014-07-22ARC: syscalls.h: code-reuse/fix-arg-annotationsVineet Gupta
- Use syscalls-common.h vers of INTERNAL_SYSCALL / INLINE_SYSCALL_NOERR - INLINE_SYSCALL takes syscall name (e.g. write) - {INLINE,INTERNAL}_SYSCALL_NCS macros take syscall num (__NR_write) Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2014-04-01ARC: Make vfork weak in libcVineet Gupta
Anton reported: ------------------->8--------------------- Package iperf cannot be built in Buildroot due to following error: /home/akolesov/env/autobuild/tmp/host/usr/bin/arc-buildroot-linux-uclibc-g++ -Wall -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -pipe -Os --static -o iperf -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -pipe -Os -pthread -DHAVE_CONFIG_H Client.o Extractor.o Launch.o List.o Listener.o Locale.o PerfSocket.o ReportCSV.o ReportDefault.o Reporter.o Server.o Settings.o SocketAddr.o gnu_getopt.o gnu_getopt_long.o main.o service.o sockets.o stdio.o tcp_window_size.o ../compat/libcompat.a /home/akolesov/env/autobuild/tmp/host/usr/arc-buildroot-linux-uclibc/sysroot/usr/lib/libc.a(vfork.os): In function `vfork': (.text+0x0): multiple definition of `vfork' /home/akolesov/env/autobuild/tmp/host/usr/arc-buildroot-linux-uclibc/sysroot/usr/lib/libpthread.a(ptfork.os):ptfork.c:(.text+0xc0): first defined here collect2: error: ld returned 1 exit status ------------------->8--------------------- Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Anton Kolesov <Anton.Kolesov@synopsys.com> Cc: Francois Bedard <Francois.Bedard@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2014-01-08ARC: opencode ENTRY/END macros in crt1Vineet Gupta
crt1.S -> include sysdep.h -> include sysnum.h In multistage gcc build, Buildroot happens to build crt1.S before sysnum.h is generated. So break the above include chain and opencode the ENTRY/END macros. Reported-by: Anton Kolesov <akolesov@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2013-12-20ARC port to uClibcVineet Gupta
For this port, I would like to give due credit to: - Folks from Codito technologies (Sameer, Amit, Kanika, Ramana,...) who did the very first port - ARC UK from 2007-2009 (Joern, Irfan, Khurram, Phil... - Late Brendan Kehoe (may he RIP) Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>