kernel/arch/arm/include/asm/traps.h, branch linux-rolling-stable

ARM: 9326/1: make self-contained for ARM

2023-10-05T15:17:05Z

When I compiled the following code for ARM, I encountered numerous errors. [Test Code] #include #include int foo(int *x, int __user *ptr) { return get_user(*x, ptr); } To fix the errors, make some asm headers self-contained: 1. In arch/arm/include/asm/domain.h, include for current_thread_info(). 2. In arch/arm/include/asm/traps.h, remove unneeded __init, and include for asmlinkage. 3. In arch/arm/include/asm/uaccess.h, include for might_fault(). Signed-off-by: Masahiro Yamada Signed-off-by: Russell King (Oracle)

ARM: 9304/1: add prototype for function called only from asm

2023-06-19T08:35:52Z

When building with 'make W=1', the compiler warns about any function definition that does not come with a prototype in a header, to ensure it matches what the caller expects. This includes functions that are only ever caller from assembly code and don't technically need a declaration: arch/arm/kernel/ftrace.c:227:6: error: no previous prototype for 'prepare_ftrace_return' arch/arm/kernel/ptrace.c:850:16: error: no previous prototype for 'syscall_trace_enter' arch/arm/kernel/ptrace.c:878:17: error: no previous prototype for 'syscall_trace_exit' arch/arm/kernel/signal.c:601:1: error: no previous prototype for 'do_work_pending' arch/arm/kernel/signal.c:672:17: error: no previous prototype for 'do_rseq_syscall' arch/arm/kernel/suspend.c:75:6: error: no previous prototype for '__cpu_suspend_save' arch/arm/kernel/traps.c:451:17: error: no previous prototype for 'do_undefinstr' arch/arm/kernel/traps.c:516:39: error: no previous prototype for 'handle_fiq_as_nmi' arch/arm/kernel/traps.c:535:17: error: no previous prototype for 'bad_mode' arch/arm/kernel/traps.c:608:16: error: no previous prototype for 'arm_syscall' arch/arm/kernel/traps.c:734:1: error: no previous prototype for 'baddataabort' arch/arm/kernel/traps.c:774:17: error: no previous prototype for '__div0' arch/arm/kernel/traps.c:97:6: error: no previous prototype for 'dump_backtrace_stm' arch/arm/kernel/unwind.c:40:6: error: no previous prototype for '__aeabi_unwind_cpp_pr0' arch/arm/kernel/unwind.c:45:6: error: no previous prototype for '__aeabi_unwind_cpp_pr1' arch/arm/kernel/unwind.c:50:6: error: no previous prototype for '__aeabi_unwind_cpp_pr2' arch/arm/mm/fault.c:554:1: error: no previous prototype for 'do_DataAbort' arch/arm/mm/fault.c:584:1: error: no previous prototype for 'do_PrefetchAbort' arch/arm/mm/proc-v7-bugs.c:280:6: error: no previous prototype for 'cpu_v7_ca8_ibe' arch/arm/mm/proc-v7-bugs.c:293:6: error: no previous prototype for 'cpu_v7_bugs_init' arch/arm/vdso/vgettimeofday.c:36:6: error: no previous prototype for '__aeabi_unwind_cpp_pr0' arch/arm/vdso/vgettimeofday.c:40:6: error: no previous prototype for '__aeabi_unwind_cpp_pr1' arch/arm/vdso/vgettimeofday.c:44:6: error: no previous prototype for '__aeabi_unwind_cpp_pr2' arch/arm/vfp/vfpmodule.c:323:6: error: no previous prototype for 'VFP_bounce' Add the prototypes anyway, to allow enabling this warning by default in the future. Reviewed-by: Kees Cook Signed-off-by: Arnd Bergmann Signed-off-by: Russell King (Oracle)

arm/asm: add loglvl to c_backtrace()

2020-06-09T16:39:10Z

Currently, the log-level of show_stack() depends on a platform realization. It creates situations where the headers are printed with lower log level or higher than the stacktrace (depending on a platform or user). Furthermore, it forces the logic decision from user to an architecture side. In result, some users as sysrq/kdb/etc are doing tricks with temporary rising console_loglevel while printing their messages. And in result it not only may print unwanted messages from other CPUs, but also omit printing at all in the unlucky case where the printk() was deferred. Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier approach than introducing more printk buffers. Also, it will consolidate printings with headers. Add log level argument to c_backtrace() as a preparation for introducing show_stack_loglvl(). [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Signed-off-by: Dmitry Safonov Signed-off-by: Andrew Morton Cc: Russell King Cc: Will Deacon Link: http://lkml.kernel.org/r/20200418201944.482088-5-dima@arista.com Signed-off-by: Linus Torvalds

signal/arm: Remove tsk parameter from ptrace_break

2019-05-29T14:31:43Z

The ptrace_break function is always called with tsk == current. Make that obvious by removing the tsk parameter. This also makes it clear that ptrace_break calls force_sig_fault on the current task. Signed-off-by: "Eric W. Biederman"

ARM: probes: avoid adding kprobes to sensitive kernel-entry/exit code

2017-12-17T22:14:21Z

Avoid adding kprobes to any of the kernel entry/exit or startup assembly code, or code in the identity-mapped region. This code does not conform to the standard C conventions, which means that the expectations of the kprobes code is not forfilled. Placing kprobes at some of these locations results in the kernel trying to return to userspace addresses while retaining the CPU in kernel mode. Tested-by: Naresh Kamboju Signed-off-by: Russell King

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is 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. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

irq: Make the irqentry text section unconditional

2017-08-10T14:28:53Z

Generate irqentry and softirqentry text sections without any Kconfig dependencies. This will add extra sections, but there should be no performace impact. Suggested-by: Ingo Molnar Signed-off-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: Anil S Keshavamurthy Cc: Chris Zankel Cc: David S . Miller Cc: Francis Deslauriers Cc: Jesper Nilsson Cc: Linus Torvalds Cc: Max Filippov Cc: Mikael Starvik Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Yoshinori Sato Cc: linux-arch@vger.kernel.org Cc: linux-cris-kernel@axis.com Cc: mathieu.desnoyers@efficios.com Link: http://lkml.kernel.org/r/150172789110.27216.3955739126693102122.stgit@devbox Signed-off-by: Ingo Molnar

ARM: earlier initialization of vectors page

2012-01-23T10:24:11Z

Initialize the contents of the vectors page immediately after we allocate the page, but before we map it. This avoids any possible aliases with other mappings which may need to be flushed after the page has been mapped irrespective of the cache type. We follow this later with a flush_cache_all() after all static memory mappings have been initialized, which ensures that this is safe from any cache effects. Tested-by: Catalin Marinas Reviewed-by: Catalin Marinas Acked-by: Nicolas Pitre Signed-off-by: Russell King

ARM: 7004/1: fix traps.h compile warnings

2011-07-22T16:19:02Z

Building kernel 3.0 for an n2100 (plat-iop) results in: In file included from arch/arm/plat-iop/cp6.c:20: /tmp/linux-3.0/arch/arm/include/asm/traps.h:12: warning: 'struct pt_regs' declared inside parameter list /tmp/linux-3.0/arch/arm/include/asm/traps.h:12: warning: its scope is only this definition or declaration, which is probably not what you want /tmp/linux-3.0/arch/arm/include/asm/traps.h:48: warning: 'struct pt_regs' declared inside parameter list /tmp/linux-3.0/arch/arm/include/asm/traps.h:48: warning: 'struct task_struct' declared inside parameter list arch/arm/plat-iop/cp6.c:45: warning: initialization from incompatible pointer type Nothing here depends on the layout of pt_regs or task_struct, so this can be fixed by adding forward struct declarations to asm/traps.h. Signed-off-by: Mikael Pettersson Signed-off-by: Russell King

ARM: 6668/1: ptrace: remove single-step emulation code

2011-02-23T17:24:22Z

PTRACE_SINGLESTEP is a ptrace request designed to offer single-stepping support to userspace when the underlying architecture has hardware support for this operation. On ARM, we set arch_has_single_step() to 1 and attempt to emulate hardware single-stepping by disassembling the current instruction to determine the next pc and placing a software breakpoint on that location. Unfortunately this has the following problems: 1.) Only a subset of ARMv7 instructions are supported 2.) Thumb-2 is unsupported 3.) The code is not SMP safe We could try to fix this code, but it turns out that because of the above issues it is rarely used in practice. GDB, for example, uses PTRACE_POKETEXT and PTRACE_PEEKTEXT to manage breakpoints itself and does not require any kernel assistance. This patch removes the single-step emulation code from ptrace meaning that the PTRACE_SINGLESTEP request will return -EIO on ARM. Portable code must check the return value from a ptrace call and handle the failure gracefully. Acked-by: Nicolas Pitre Signed-off-by: Will Deacon Signed-off-by: Russell King