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* s390: remove compat vdso codeHeiko Carstens2019-12-011-44/+0
| | | | | | | | | Remove compat vdso code, since there is hardly any compat user space left. Still existing compat user space will have to use system calls instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390/vdso: revise CFI annotations of vDSO functionsHendrik Brueckner2017-12-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | | Revise and add CFI CFA and register rule annotations to the vDSO functions for proper stack unwinding and debugging. Because glibc might call the vDSO in special ways, the vDSO code does not rely on a stack frame created by the caller. The TOD clock value can be therefore not stored in the pre-allocated stack area and additional stack space is required. To correctly annotate these situations with CFI, the .cfi_val_offset directive is required to create relative offsets on the value of the stack register %r15. Because the .cfi_val_offset directive is available with recent GNU assembler versions only, additional checks are necessary. Note that if the vDSO is assembled with an older assembler version, stack unwinding and debugging from within the vDSO code might not be possible. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kernel: emit CFI data in .debug_frame and discard .eh_frame sectionsHendrik Brueckner2017-12-131-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Using perf probe and libdw on kernel modules failed to find CFI data for symbols. The CFI data is stored in the .eh_frame section. The elfutils libdw is not able to extract the CFI data correctly, because the .eh_frame section requires "non-simple" relocations for kernel modules. The suggestion is to avoid these "non-simple" relocations by emitting the CFI data in the .debug_frame section. Let gcc emit respective directives by specifying the -fno-asynchronous-unwind-tables option. Using the .debug_frame section for CFI data, the .eh_frame section becomes unused and, thus, discard it for kernel and modules builds The vDSO requires the .eh_frame section and, hence, emit the CFI data in both, the .eh_frame and .debug_frame sections. See also discussion on elfutils/libdw bugzilla: https://sourceware.org/bugzilla/show_bug.cgi?id=22452 Suggested-by: Mark Wielaard <mark@klomp.org> Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: kernel: Remove redundant license textGreg Kroah-Hartman2017-11-241-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | Now that the SPDX tag is in all arch/s390/kernel/ files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: kernel: add SPDX identifiers to the remaining filesGreg Kroah-Hartman2017-11-241-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the arch/s390/kernel/ files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/vdso: add vdso support for coarse clocksMartin Schwidefsky2014-09-091-2/+9
| | | | | | | Add CLOCK_REALTIME_COARSE and CLOCK_MONOTONIC_COARSE optimization to the 64-bit and 31-bit vdso. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] vdso: get rid of redefinition warningsHeiko Carstens2010-10-291-3/+3
| | | | | | | | | | | | | | | | The CLOCK_* defines in asm-offsets.c are only used for the vdso code however in the meantime they cause other trouble. Just rename them to get permanently rid of this: In file included from /home2/heicarst/linux-2.6/arch/s390/include/asm/asm-offsets.h:1:0, from arch/s390/mm/fault.c:33: include/generated/asm-offsets.h:53:0: warning: "CLOCK_REALTIME" redefined include/linux/time.h:286:0: note: this is the location of the previous definition include/generated/asm-offsets.h:54:0: warning: "CLOCK_MONOTONIC" redefined include/linux/time.h:287:0: note: this is the location of the previous definition Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] introduce vdso on s390Martin Schwidefsky2008-12-251-0/+39
Add a vdso to speed up gettimeofday and clock_getres/clock_gettime for CLOCK_REALTIME/CLOCK_MONOTONIC. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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