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2024-02-15membarrier: riscv: Provide core serializing commandAndrea Parri1-1/+17
RISC-V uses xRET instructions on return from interrupt and to go back to user-space; the xRET instruction is not core serializing. Use FENCE.I for providing core serialization as follows: - by calling sync_core_before_usermode() on return from interrupt (cf. ipi_sync_core()), - via switch_mm() and sync_core_before_usermode() (respectively, for uthread->uthread and kthread->uthread transitions) before returning to user-space. On RISC-V, the serialization in switch_mm() is activated by resetting the icache_stale_mask of the mm at prepare_sync_core_cmd(). Suggested-by: Palmer Dabbelt <palmer@dabbelt.com> Signed-off-by: Andrea Parri <parri.andrea@gmail.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://lore.kernel.org/r/20240131144936.29190-5-parri.andrea@gmail.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-09-11Documentation: Drop IA64 from feature descriptionsArd Biesheuvel2-2/+0
Itanium (IA64) is going away, so drop it from the kernel feature documentation. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-03-27s390: enable ARCH_HAS_MEMBARRIER_SYNC_COREHeiko Carstens1-2/+2
s390 trivially supports the ARCH_HAS_MEMBARRIER_SYNC_CORE requirements since the used lpswe(y) instruction to return from any kernel context to user space performs CPU serialization. This is very similar to arm, arm64 and powerpc. See commit 70216e18e519 ("membarrier: Provide core serializing command, *_SYNC_CORE") for further details. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2022-12-05Documentation/features: Use loongarch instead of loongTiezhu Yang2-2/+2
The official arch name is LoongArch [1], we should use small letter loongarch instead of loong in Documentation/features, just use the features-refresh.sh to refresh all the related files. [1] https://www.kernel.org/doc/html/latest/loongarch/index.html Fixes: 5860800e8696 ("Documentation/features: Update the arch support status files") Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Link: https://lore.kernel.org/r/1670156327-9631-3-git-send-email-yangtiezhu@loongson.cn Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-06-09Documentation/features: Update the arch support status filesZheng Zengkai2-0/+2
The arch support status files don't match reality as of v5.19-rc1, use the features-refresh.sh to refresh all the arch-support.txt files in place. The main effect is to add entries for the new loong architecture. Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Link: https://lore.kernel.org/r/20220609025656.143460-1-zhengzengkai@huawei.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-04-04Merge branch 'remove-h8300' of git://git.infradead.org/users/hch/misc into ↵Arnd Bergmann2-2/+0
asm-generic * 'remove-h8300' of git://git.infradead.org/users/hch/misc: remove the h8300 architecture This is clearly the least actively maintained architecture we have at the moment, and probably the least useful. It is now the only one that does not support MMUs at all, and most of the boards only support 4MB of RAM, out of which the defconfig kernel needs more than half just for .text/.data. Guenter Roeck did the original patch to remove the architecture in 2013 after it had already been obsolete for a while, and Yoshinori Sato brought it back in a much more modern form in 2015. Looking at the git history since the reinstantiation, it's clear that almost all commits in the tree are build fixes or cross-architecture cleanups: $ git log --no-merges --format=%an v4.5.. arch/h8300/ | sort | uniq -c | sort -rn | head -n 12 25 Masahiro Yamada 18 Christoph Hellwig 14 Mike Rapoport 9 Arnd Bergmann 8 Mark Rutland 7 Peter Zijlstra 6 Kees Cook 6 Ingo Molnar 6 Al Viro 5 Randy Dunlap 4 Yury Norov Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-03-07nds32: Remove the architectureAlan Kao2-2/+0
The nds32 architecture, also known as AndeStar V3, is a custom 32-bit RISC target designed by Andes Technologies. Support was added to the kernel in 2016 as the replacement RISC-V based V5 processors were already announced, and maintained by (current or former) Andes employees. As explained by Alan Kao, new customers are now all using RISC-V, and all known nds32 users are already on longterm stable kernels provided by Andes, with no development work going into mainline support any more. While the port is still in a reasonably good shape, it only gets worse over time without active maintainers, so it seems best to remove it before it becomes unusable. As always, if it turns out that there are mainline users after all, and they volunteer to maintain the port in the future, the removal can be reverted. Link: https://lore.kernel.org/linux-mm/YhdWNLUhk+x9RAzU@yamatobi.andestech.com/ Link: https://lore.kernel.org/lkml/20220302065213.82702-1-alankao@andestech.com/ Link: https://www.andestech.com/en/products-solutions/andestar-architecture/ Signed-off-by: Alan Kao <alankao@andestech.com> [arnd: rewrite changelog to provide more background] Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-02-23remove the h8300 architectureChristoph Hellwig2-2/+0
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-02-25Documentation: features: refresh feature listArnd Bergmann1-1/+1
Run the update script to document the recent feature additions on riscv, mips and csky. Fixes: c109f42450ec ("csky: Add kmemleak support") Fixes: 8b3165e54566 ("MIPS: Enable GCOV") Fixes: 1ddc96bd42da ("MIPS: kernel: Support extracting off-line stack traces from user-space with perf") Fixes: 74784081aac8 ("riscv: Add uprobes supported") Fixes: 829adda597fe ("riscv: Add KPROBES_ON_FTRACE supported") Fixes: c22b0bcb1dd0 ("riscv: Add kprobes supported") Fixes: dcdc7a53a890 ("RISC-V: Implement ptrace regs and stack API") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20210225142841.3385428-2-arnd@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-02-25Documentation: features: remove c6x referencesArnd Bergmann2-2/+0
The references to arch/c6x are obsolete now that the architecture is gone. Remove them. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20210225142841.3385428-1-arnd@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-08-07Merge tag 'powerpc-5.9-1' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Add support for (optionally) using queued spinlocks & rwlocks. - Support for a new faster system call ABI using the scv instruction on Power9 or later. - Drop support for the PROT_SAO mmap/mprotect flag as it will be unsupported on Power10 and future processors, leaving us with no way to implement the functionality it requests. This risks breaking userspace, though we believe it is unused in practice. - A bug fix for, and then the removal of, our custom stack expansion checking. We now allow stack expansion up to the rlimit, like other architectures. - Remove the remnants of our (previously disabled) topology update code, which tried to react to NUMA layout changes on virtualised systems, but was prone to crashes and other problems. - Add PMU support for Power10 CPUs. - A change to our signal trampoline so that we don't unbalance the link stack (branch return predictor) in the signal delivery path. - Lots of other cleanups, refactorings, smaller features and so on as usual. Thanks to: Abhishek Goel, Alastair D'Silva, Alexander A. Klimov, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Balamuruhan S, Bharata B Rao, Bill Wendling, Bin Meng, Cédric Le Goater, Chris Packham, Christophe Leroy, Christoph Hellwig, Daniel Axtens, Dan Williams, David Lamparter, Desnes A. Nunes do Rosario, Erhard F., Finn Thain, Frederic Barrat, Ganesh Goudar, Gautham R. Shenoy, Geoff Levand, Greg Kurz, Gustavo A. R. Silva, Hari Bathini, Harish, Imre Kaloz, Joel Stanley, Joe Perches, John Crispin, Jordan Niethe, Kajol Jain, Kamalesh Babulal, Kees Cook, Laurent Dufour, Leonardo Bras, Li RongQing, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Cave-Ayland, Michal Suchanek, Milton Miller, Mimi Zohar, Murilo Opsfelder Araujo, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nayna Jain, Nicholas Piggin, Oliver O'Halloran, Palmer Dabbelt, Pedro Miraglia Franco de Carvalho, Philippe Bergheaud, Pingfan Liu, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Randy Dunlap, Ravi Bangoria, Sachin Sant, Sam Bobroff, Sandipan Das, Santosh Sivaraj, Satheesh Rajendran, Shirisha Ganta, Sourabh Jain, Srikar Dronamraju, Stan Johnson, Stephen Rothwell, Thadeu Lima de Souza Cascardo, Thiago Jung Bauermann, Tom Lane, Vaibhav Jain, Vladis Dronov, Wei Yongjun, Wen Xiong, YueHaibing. * tag 'powerpc-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (337 commits) selftests/powerpc: Fix pkey syscall redefinitions powerpc: Fix circular dependency between percpu.h and mmu.h powerpc/powernv/sriov: Fix use of uninitialised variable selftests/powerpc: Skip vmx/vsx/tar/etc tests on older CPUs powerpc/40x: Fix assembler warning about r0 powerpc/papr_scm: Add support for fetching nvdimm 'fuel-gauge' metric powerpc/papr_scm: Fetch nvdimm performance stats from PHYP cpuidle: pseries: Fixup exit latency for CEDE(0) cpuidle: pseries: Add function to parse extended CEDE records cpuidle: pseries: Set the latency-hint before entering CEDE selftests/powerpc: Fix online CPU selection powerpc/perf: Consolidate perf_callchain_user_[64|32]() powerpc/pseries/hotplug-cpu: Remove double free in error path powerpc/pseries/mobility: Add pr_debug() for device tree changes powerpc/pseries/mobility: Set pr_fmt() powerpc/cacheinfo: Warn if cache object chain becomes unordered powerpc/cacheinfo: Improve diagnostics about malformed cache lists powerpc/cacheinfo: Use name@unit instead of full DT path in debug messages powerpc/cacheinfo: Set pr_fmt() powerpc: fix function annotations to avoid section mismatch warnings with gcc-10 ...
2020-07-23powerpc: Select ARCH_HAS_MEMBARRIER_SYNC_CORENicholas Piggin1-2/+2
powerpc return from interrupt and return from system call sequences are context synchronising. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200716013522.338318-1-npiggin@gmail.com
2020-07-01arch: remove unicore32 portMike Rapoport2-2/+0
The unicore32 port do not seem maintained for a long time now, there is no upstream toolchain that can create unicore32 binaries and all the links to prebuilt toolchains for unicore32 are dead. Even compilers that were available are not supported by the kernel anymore. Guenter Roeck says: I have stopped building unicore32 images since v4.19 since there is no available compiler that is still supported by the kernel. I am surprised that support for it has not been removed from the kernel. Remove unicore32 port. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Guenter Roeck <linux@roeck-us.net>
2019-01-07Documentation/features: Add csky kernel featuresGuo Ren2-0/+2
core/ cBPF-JIT : TODO | core/ eBPF-JIT : TODO | core/ generic-idle-thread : ok | core/ jump-labels : TODO | core/ tracehook : ok | debug/ KASAN : TODO | debug/ gcov-profile-all : TODO | debug/ kgdb : TODO | debug/ kprobes-on-ftrace : TODO | debug/ kprobes : TODO | debug/ kretprobes : TODO | debug/ optprobes : TODO | debug/ stackprotector : TODO | debug/ uprobes : TODO | debug/ user-ret-profiler : TODO | io/ dma-contiguous : ok | locking/ cmpxchg-local : TODO | locking/ lockdep : TODO | locking/ queued-rwlocks : ok | locking/ queued-spinlocks : TODO | locking/ rwsem-optimized : TODO | perf/ kprobes-event : TODO | perf/ perf-regs : TODO | perf/ perf-stackdump : TODO | sched/ membarrier-sync-core : TODO | sched/ numa-balancing : .. | seccomp/ seccomp-filter : TODO | time/ arch-tick-broadcast : TODO | time/ clockevents : ok | time/ context-tracking : TODO | time/ irq-time-acct : TODO | time/ modern-timekeeping : ok | time/ virt-cpuacct : TODO | vm/ ELF-ASLR : TODO | vm/ PG_uncached : TODO | vm/ THP : .. | vm/ batch-unmap-tlb-flush: TODO | vm/ huge-vmap : TODO | vm/ ioremap_prot : TODO | vm/ numa-memblock : .. | vm/ pte_special : TODO | Signed-off-by: Guo Ren <ren_guo@c-sky.com> Cc: Arnd Bergmann <arnd@arndb.de>
2018-07-11ARM: 8777/1: Hook up SYNC_CORE functionality for sys_membarrier()Will Deacon1-4/+4
Exception return implies context synchronization, so we can hook up the SYNC_CORE option to sys_membarrier() simply by selecting the Kconfig option, just like we've done for arm64 already. Cc: Orion Hodson <oth@google.com> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-05-08Documentation/features: Refresh the arch support status files in placeAndrea Parri2-2/+6
Now that the script 'features-refresh.sh' is available, uses this script to refresh all the arch-support.txt files in place. Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-03-26Documentation: arch-support: remove obsolete architecturesArnd Bergmann2-12/+0
A number of architecture ports are obsolete and getting dropped, so we no longer want to track the respective features. We already removed the lines for metag and mn10300, this does the same edits for all the others. For the remaining 21 architectures, this shows how many are known to implement each given feature: 19 time/modern-timekeeping/arch-support.txt 19 time/clockevents/arch-support.txt 15 core/tracehook/arch-support.txt 14 core/generic-idle-thread/arch-support.txt 13 locking/lockdep/arch-support.txt 12 io/dma-api-debug/arch-support.txt 11 debug/kgdb/arch-support.txt 10 time/virt-cpuacct/arch-support.txt 9 debug/kretprobes/arch-support.txt 9 debug/kprobes/arch-support.txt 8 vm/THP/arch-support.txt 8 vm/pte_special/arch-support.txt 8 vm/numa-memblock/arch-support.txt 8 io/sg-chain/arch-support.txt 7 perf/kprobes-event/arch-support.txt 7 locking/rwsem-optimized/arch-support.txt 7 debug/gcov-profile-all/arch-support.txt 7 core/jump-labels/arch-support.txt 7 core/BPF-JIT/arch-support.txt 6 vm/ELF-ASLR/arch-support.txt 6 time/context-tracking/arch-support.txt 6 seccomp/seccomp-filter/arch-support.txt 6 debug/stackprotector/arch-support.txt 5 time/irq-time-acct/arch-support.txt 5 io/dma-contiguous/arch-support.txt 5 debug/uprobes/arch-support.txt 4 vm/ioremap_prot/arch-support.txt 4 time/arch-tick-broadcast/arch-support.txt 4 perf/perf-stackdump/arch-support.txt 4 perf/perf-regs/arch-support.txt 3 debug/KASAN/arch-support.txt 2 vm/PG_uncached/arch-support.txt 2 vm/huge-vmap/arch-support.txt 2 sched/numa-balancing/arch-support.txt 2 sched/membarrier-sync-core/arch-support.txt 2 locking/cmpxchg-local/arch-support.txt 2 debug/optprobes/arch-support.txt 2 debug/kprobes-on-ftrace/arch-support.txt 1 vm/TLB/arch-support.txt 1 locking/queued-spinlocks/arch-support.txt 1 locking/queued-rwlocks/arch-support.txt 1 debug/user-ret-profiler/arch-support.txt 0 lib/strncasecmp/arch-support.txt Note that the list does not include riscv or nds32 yet, these still need to be added. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-03-10mn10300: Remove the architectureDavid Howells2-2/+0
Remove the MN10300 arch as the hardware is defunct. Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David Howells <dhowells@redhat.com> cc: Masahiro Yamada <yamada.masahiro@socionext.com> cc: linux-am33-list@redhat.com Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22docs: Remove remaining references to metagJames Hogan2-2/+0
Remove any remaining references to the Meta architecture in Documentation/, primarily from Documentation/features/. Signed-off-by: James Hogan <jhogan@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-metag@vger.kernel.org Cc: linux-doc@vger.kernel.org
2018-02-10membarrier-sync-core: Document architecture supportMathieu Desnoyers1-0/+62
Ensure we gather architecture requirements about each architecture supporting the "sync_core" membarrier command in a single file under Documentation/features. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrea Parri <parri.andrea@gmail.com> Cc: Andrew Hunter <ahh@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Avi Kivity <avi@scylladb.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Dave Watson <davejwatson@fb.com> Cc: David Sehr <sehr@google.com> Cc: Greg Hackmann <ghackmann@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maged Michael <maged.michael@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-api@vger.kernel.org Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/1518208256-22034-1-git-send-email-mathieu.desnoyers@efficios.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-01docs: remove all references to AVR32 architectureHans-Christian Noren Egtvedt1-1/+0
The AVR32 architecture support has been removed from the Linux kernel, hence remove all references to it from Documentation. Signed-off-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> Signed-off-by: Håvard Skinnemoen <hskinnemoen@gmail.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2015-06-03Documentation/features/sched: Add feature description and arch support ↵Ingo Molnar1-0/+40
status file for 'numa-balancing' Cc: <linux-api@vger.kernel.org> Cc: <linux-arch@vger.kernel.org> Cc: <linux-kernel@vger.kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>