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2023-09-11arch: Remove Itanium (IA-64) architectureArd Biesheuvel1-138/+0
The Itanium architecture is obsolete, and an informal survey [0] reveals that any residual use of Itanium hardware in production is mostly HP-UX or OpenVMS based. The use of Linux on Itanium appears to be limited to enthusiasts that occasionally boot a fresh Linux kernel to see whether things are still working as intended, and perhaps to churn out some distro packages that are rarely used in practice. None of the original companies behind Itanium still produce or support any hardware or software for the architecture, and it is listed as 'Orphaned' in the MAINTAINERS file, as apparently, none of the engineers that contributed on behalf of those companies (nor anyone else, for that matter) have been willing to support or maintain the architecture upstream or even be responsible for applying the odd fix. The Intel firmware team removed all IA-64 support from the Tianocore/EDK2 reference implementation of EFI in 2018. (Itanium is the original architecture for which EFI was developed, and the way Linux supports it deviates significantly from other architectures.) Some distros, such as Debian and Gentoo, still maintain [unofficial] ia64 ports, but many have dropped support years ago. While the argument is being made [1] that there is a 'for the common good' angle to being able to build and run existing projects such as the Grid Community Toolkit [2] on Itanium for interoperability testing, the fact remains that none of those projects are known to be deployed on Linux/ia64, and very few people actually have access to such a system in the first place. Even if there were ways imaginable in which Linux/ia64 could be put to good use today, what matters is whether anyone is actually doing that, and this does not appear to be the case. There are no emulators widely available, and so boot testing Itanium is generally infeasible for ordinary contributors. GCC still supports IA-64 but its compile farm [3] no longer has any IA-64 machines. GLIBC would like to get rid of IA-64 [4] too because it would permit some overdue code cleanups. In summary, the benefits to the ecosystem of having IA-64 be part of it are mostly theoretical, whereas the maintenance overhead of keeping it supported is real. So let's rip off the band aid, and remove the IA-64 arch code entirely. This follows the timeline proposed by the Debian/ia64 maintainer [5], which removes support in a controlled manner, leaving IA-64 in a known good state in the most recent LTS release. Other projects will follow once the kernel support is removed. [0] https://lore.kernel.org/all/CAMj1kXFCMh_578jniKpUtx_j8ByHnt=s7S+yQ+vGbKt9ud7+kQ@mail.gmail.com/ [1] https://lore.kernel.org/all/0075883c-7c51-00f5-2c2d-5119c1820410@web.de/ [2] https://gridcf.org/gct-docs/latest/index.html [3] https://cfarm.tetaneutral.net/machines/list/ [4] https://lore.kernel.org/all/87bkiilpc4.fsf@mid.deneb.enyo.de/ [5] https://lore.kernel.org/all/ff58a3e76e5102c94bb5946d99187b358def688a.camel@physik.fu-berlin.de/ Acked-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-08-18arch/ia64/include: remove CONFIG_IA64_DEBUG_CMPXCHG from uapi headerThomas Huth1-17/+0
CONFIG_* switches should not be exposed in uapi headers. The macros that are defined here are also only useful for the kernel code, so let's move them to asm/cmpxchg.h instead. The only two files that are using these macros are the headers arch/ia64/include/asm/bitops.h and arch/ia64/include/asm/atomic.h and these include asm/cmpxchg.h via asm/intrinsics.h, so this movement should not cause any trouble. Link: https://lkml.kernel.org/r/20230426065032.517693-1-thuth@redhat.com Signed-off-by: Thomas Huth <thuth@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-29locking/arch: Rename all internal __xchg() names to __arch_xchg()Andrzej Hajda1-2/+2
Decrease the probability of this internal facility to be used by driver code. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Acked-by: Palmer Dabbelt <palmer@rivosinc.com> [riscv] Link: https://lore.kernel.org/r/20230118154450.73842-1-andrzej.hajda@intel.com Cc: Linus Torvalds <torvalds@linux-foundation.org>
2023-03-05Remove Intel compiler supportMasahiro Yamada1-5/+1
include/linux/compiler-intel.h had no update in the past 3 years. We often forget about the third C compiler to build the kernel. For example, commit a0a12c3ed057 ("asm goto: eradicate CC_HAS_ASM_GOTO") only mentioned GCC and Clang. init/Kconfig defines CC_IS_GCC and CC_IS_CLANG but not CC_IS_ICC, and nobody has reported any issue. I guess the Intel Compiler support is broken, and nobody is caring about it. Harald Arnesen pointed out ICC (classic Intel C/C++ compiler) is deprecated: $ icc -v icc: remark #10441: The Intel(R) C++ Compiler Classic (ICC) is deprecated and will be removed from product release in the second half of 2023. The Intel(R) oneAPI DPC++/C++ Compiler (ICX) is the recommended compiler moving forward. Please transition to use this compiler. Use '-diag-disable=10441' to disable this message. icc version 2021.7.0 (gcc version 12.1.0 compatibility) Arnd Bergmann provided a link to the article, "Intel C/C++ compilers complete adoption of LLVM". lib/zstd/common/compiler.h and lib/zstd/compress/zstd_fast.c were kept untouched for better sync with https://github.com/facebook/zstd Link: https://www.intel.com/content/www/us/en/developer/articles/technical/adoption-of-llvm-complete-icx.html Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-06-16ia64: fix sparse warnings with cmpxchg() & xchg()Luc Van Oostenryck1-14/+14
On IA64, new sparse's warnings where issued after fixing some __rcu annotations in kernel/bpf/. These new warnings are false positives and appear on IA64 because on this architecture, the macros for cmpxchg() and xchg() make casts that ignore sparse annotations. This patch contains the minimal patch to fix this issue: adding a missing cast and some missing '__force'. Link: https://lore.kernel.org/r/20220601120013.bq5a3ynbkc3hngm5@mail Link: https://lkml.kernel.org/r/20220605160738.79736-1-luc.vanoostenryck@gmail.com Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Reported-by: kernel test robot <lkp@intel.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2021-07-19printk: Userspace format indexing supportChris Down1-2/+2
We have a number of systems industry-wide that have a subset of their functionality that works as follows: 1. Receive a message from local kmsg, serial console, or netconsole; 2. Apply a set of rules to classify the message; 3. Do something based on this classification (like scheduling a remediation for the machine), rinse, and repeat. As a couple of examples of places we have this implemented just inside Facebook, although this isn't a Facebook-specific problem, we have this inside our netconsole processing (for alarm classification), and as part of our machine health checking. We use these messages to determine fairly important metrics around production health, and it's important that we get them right. While for some kinds of issues we have counters, tracepoints, or metrics with a stable interface which can reliably indicate the issue, in order to react to production issues quickly we need to work with the interface which most kernel developers naturally use when developing: printk. Most production issues come from unexpected phenomena, and as such usually the code in question doesn't have easily usable tracepoints or other counters available for the specific problem being mitigated. We have a number of lines of monitoring defence against problems in production (host metrics, process metrics, service metrics, etc), and where it's not feasible to reliably monitor at another level, this kind of pragmatic netconsole monitoring is essential. As one would expect, monitoring using printk is rather brittle for a number of reasons -- most notably that the message might disappear entirely in a new version of the kernel, or that the message may change in some way that the regex or other classification methods start to silently fail. One factor that makes this even harder is that, under normal operation, many of these messages are never expected to be hit. For example, there may be a rare hardware bug which one wants to detect if it was to ever happen again, but its recurrence is not likely or anticipated. This precludes using something like checking whether the printk in question was printed somewhere fleetwide recently to determine whether the message in question is still present or not, since we don't anticipate that it should be printed anywhere, but still need to monitor for its future presence in the long-term. This class of issue has happened on a number of occasions, causing unhealthy machines with hardware issues to remain in production for longer than ideal. As a recent example, some monitoring around blk_update_request fell out of date and caused semi-broken machines to remain in production for longer than would be desirable. Searching through the codebase to find the message is also extremely fragile, because many of the messages are further constructed beyond their callsite (eg. btrfs_printk and other module-specific wrappers, each with their own functionality). Even if they aren't, guessing the format and formulation of the underlying message based on the aesthetics of the message emitted is not a recipe for success at scale, and our previous issues with fleetwide machine health checking demonstrate as much. This provides a solution to the issue of silently changed or deleted printks: we record pointers to all printk format strings known at compile time into a new .printk_index section, both in vmlinux and modules. At runtime, this can then be iterated by looking at <debugfs>/printk/index/<module>, which emits the following format, both readable by humans and able to be parsed by machines: $ head -1 vmlinux; shuf -n 5 vmlinux # <level[,flags]> filename:line function "format" <5> block/blk-settings.c:661 disk_stack_limits "%s: Warning: Device %s is misaligned\n" <4> kernel/trace/trace.c:8296 trace_create_file "Could not create tracefs '%s' entry\n" <6> arch/x86/kernel/hpet.c:144 _hpet_print_config "hpet: %s(%d):\n" <6> init/do_mounts.c:605 prepare_namespace "Waiting for root device %s...\n" <6> drivers/acpi/osl.c:1410 acpi_no_auto_serialize_setup "ACPI: auto-serialization disabled\n" This mitigates the majority of cases where we have a highly-specific printk which we want to match on, as we can now enumerate and check whether the format changed or the printk callsite disappeared entirely in userspace. This allows us to catch changes to printks we monitor earlier and decide what to do about it before it becomes problematic. There is no additional runtime cost for printk callers or printk itself, and the assembly generated is exactly the same. Signed-off-by: Chris Down <chris@chrisdown.name> Cc: Petr Mladek <pmladek@suse.com> Cc: Jessica Yu <jeyu@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Tested-by: Petr Mladek <pmladek@suse.com> Reported-by: kernel test robot <lkp@intel.com> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Jessica Yu <jeyu@kernel.org> # for module.{c,h} Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/e42070983637ac5e384f17fbdbe86d19c7b212a5.1623775748.git.chris@chrisdown.name
2021-05-26locking/atomic: ia64: move to ARCH_ATOMICMark Rutland1-3/+7
We'd like all architectures to convert to ARCH_ATOMIC, as once all architectures are converted it will be possible to make significant cleanups to the atomics headers, and this will make it much easier to generically enable atomic functionality (e.g. debug logic in the instrumented wrappers). As a step towards that, this patch migrates ia64 to ARCH_ATOMIC. The arch code provides arch_{atomic,atomic64,xchg,cmpxchg}*(), and common code wraps these with optional instrumentation to provide the regular functions. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20210525140232.53872-20-mark.rutland@arm.com
2021-01-12ia64: fix xchg() warningArnd Bergmann1-1/+1
The definition if xchg() causes a harmless warning in some files, like: In file included from ../arch/ia64/include/uapi/asm/intrinsics.h:22, from ../arch/ia64/include/asm/intrinsics.h:11, from ../arch/ia64/include/asm/bitops.h:19, from ../include/linux/bitops.h:32, from ../include/linux/kernel.h:11, from ../fs/nfs/read.c:12: ../fs/nfs/read.c: In function 'nfs_read_completion': ../arch/ia64/include/uapi/asm/cmpxchg.h:57:2: warning: value computed is not used [-Wunused-value] 57 | ((__typeof__(*(ptr))) __xchg((unsigned long) (x), (ptr), sizeof(*(ptr)))) | ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ../fs/nfs/read.c:196:5: note: in expansion of macro 'xchg' 196 | xchg(&nfs_req_openctx(req)->error, error); | ^~~~ Change it to a compound expression like the other architectures have to get a clean defconfig build. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2017-11-02License cleanup: add SPDX license identifier to uapi header files with no ↵Greg Kroah-Hartman1-0/+1
license Many user space API headers are missing licensing information, which makes it hard for compliance tools to determine the correct license. By default are files without license information under the default license of the kernel, which is GPLV2. Marking them GPLV2 would exclude them from being included in non GPLV2 code, which is obviously not intended. The user space API headers fall under the syscall exception which is in the kernels COPYING file: NOTE! This copyright does *not* cover user programs that use kernel services by normal system calls - this is merely considered normal use of the kernel, and does *not* fall under the heading of "derived work". otherwise syscall usage would not be possible. Update the files which contain no license information with an SPDX license identifier. The chosen identifier is 'GPL-2.0 WITH Linux-syscall-note' which is the officially assigned identifier for the Linux syscall exception. SPDX license identifiers are a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. See the previous patch in this series for the methodology of how this patch was researched. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-13arch: Remove __ARCH_HAVE_CMPXCHGThomas Gleixner1-2/+0
We removed the only user of this define in the rtmutex code. Get rid of it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
2014-04-18ia64: Fix up smp_mb__{before,after}_clear_bit()Peter Zijlstra1-0/+9
IA64 doesn't actually have acquire/release barriers, its a lie! Add a comment explaining this and fix up the bitop barriers. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/n/tip-akevfh136um9dqvb1ohm55ca@git.kernel.org Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-ia64@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-10-09UAPI: (Scripted) Disintegrate arch/ia64/include/asmDavid Howells1-0/+147
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Kerrisk <mtk.manpages@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com>