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2022-11-08ARM: 9263/1: use .arch directives instead of assembler command line flagsNick Desaulniers
Similar to commit a6c30873ee4a ("ARM: 8989/1: use .fpu assembler directives instead of assembler arguments"). GCC and GNU binutils support setting the "sub arch" via -march=, -Wa,-march, target function attribute, and .arch assembler directive. Clang was missing support for -Wa,-march=, but this was implemented in clang-13. The behavior of both GCC and Clang is to prefer -Wa,-march= over -march= for assembler and assembler-with-cpp sources, but Clang will warn about the -march= being unused. clang: warning: argument unused during compilation: '-march=armv6k' [-Wunused-command-line-argument] Since most assembler is non-conditionally assembled with one sub arch (modulo arch/arm/delay-loop.S which conditionally is assembled as armv4 based on CONFIG_ARCH_RPC, and arch/arm/mach-at91/pm-suspend.S which is conditionally assembled as armv7-a based on CONFIG_CPU_V7), prefer the .arch assembler directive. Add a few more instances found in compile testing as found by Arnd and Nathan. Link: https://github.com/llvm/llvm-project/commit/1d51c699b9e2ebc5bcfdbe85c74cc871426333d4 Link: https://bugs.llvm.org/show_bug.cgi?id=48894 Link: https://github.com/ClangBuiltLinux/linux/issues/1195 Link: https://github.com/ClangBuiltLinux/linux/issues/1315 Suggested-by: Arnd Bergmann <arnd@arndb.de> Suggested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2022-02-25uaccess: fix type mismatch warnings from access_ok()Arnd Bergmann
On some architectures, access_ok() does not do any argument type checking, so replacing the definition with a generic one causes a few warnings for harmless issues that were never caught before. Fix the ones that I found either through my own test builds or that were reported by the 0-day bot. Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-06-09mmap locking API: use coccinelle to convert mmap_sem rwsem call sitesMichel Lespinasse
This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-03Remove 'type' argument from access_ok() functionLinus Torvalds
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-09-27signal/arm: Push siginfo generation into arm_notify_dieEric W. Biederman
In arm_notify_die call force_sig_fault to let the generic code handle siginfo generation. This removes some boiler plate making the code easier to maintain in the long run. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-06-04Merge branch 'siginfo-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull siginfo updates from Eric Biederman: "This set of changes close the known issues with setting si_code to an invalid value, and with not fully initializing struct siginfo. There remains work to do on nds32, arc, unicore32, powerpc, arm, arm64, ia64 and x86 to get the code that generates siginfo into a simpler and more maintainable state. Most of that work involves refactoring the signal handling code and thus careful code review. Also not included is the work to shrink the in kernel version of struct siginfo. That depends on getting the number of places that directly manipulate struct siginfo under control, as it requires the introduction of struct kernel_siginfo for the in kernel things. Overall this set of changes looks like it is making good progress, and with a little luck I will be wrapping up the siginfo work next development cycle" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits) signal/sh: Stop gcc warning about an impossible case in do_divide_error signal/mips: Report FPE_FLTUNK for undiagnosed floating point exceptions signal/um: More carefully relay signals in relay_signal. signal: Extend siginfo_layout with SIL_FAULT_{MCEERR|BNDERR|PKUERR} signal: Remove unncessary #ifdef SEGV_PKUERR in 32bit compat code signal/signalfd: Add support for SIGSYS signal/signalfd: Remove __put_user from signalfd_copyinfo signal/xtensa: Use force_sig_fault where appropriate signal/xtensa: Consistenly use SIGBUS in do_unaligned_user signal/um: Use force_sig_fault where appropriate signal/sparc: Use force_sig_fault where appropriate signal/sparc: Use send_sig_fault where appropriate signal/sh: Use force_sig_fault where appropriate signal/s390: Use force_sig_fault where appropriate signal/riscv: Replace do_trap_siginfo with force_sig_fault signal/riscv: Use force_sig_fault where appropriate signal/parisc: Use force_sig_fault where appropriate signal/parisc: Use force_sig_mceerr where appropriate signal/openrisc: Use force_sig_fault where appropriate signal/nios2: Use force_sig_fault where appropriate ...
2018-05-16proc: introduce proc_create_single{,_data}Christoph Hellwig
Variants of proc_create{,_data} that directly take a seq_file show callback and drastically reduces the boilerplate code in the callers. All trivial callers converted over. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-04-25signal: Ensure every siginfo we send has all bits initializedEric W. Biederman
Call clear_siginfo to ensure every stack allocated siginfo is properly initialized before being passed to the signal sending functions. Note: It is not safe to depend on C initializers to initialize struct siginfo on the stack because C is allowed to skip holes when initializing a structure. The initialization of struct siginfo in tracehook_report_syscall_exit was moved from the helper user_single_step_siginfo into tracehook_report_syscall_exit itself, to make it clear that the local variable siginfo gets fully initialized. In a few cases the scope of struct siginfo has been reduced to make it clear that siginfo siginfo is not used on other paths in the function in which it is declared. Instances of using memset to initialize siginfo have been replaced with calls clear_siginfo for clarity. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2017-03-02sched/headers: Prepare to remove the <linux/mm_types.h> dependency from ↵Ingo Molnar
<linux/sched.h> Update code that relied on sched.h including various MM types for them. This will allow us to remove the <linux/mm_types.h> include from <linux/sched.h>. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-12-15ARM: 8475/1: SWP emulation: Restore original *data when failedShengjiu Wang
__user_swpX_asm maybe failed in first STREX operation, emulate_swpX will try again, but the *data has been changed in first time. which causes the result is wrong. This patch is to fix this issue. When STREX succeed, change the *data. if it fail, *data is not changed. Signed-off-by: Shengjiu Wang <shengjiu.wang@freescale.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-08-26ARM: software-based priviledged-no-access supportRussell King
Provide a software-based implementation of the priviledged no access support found in ARMv8.1. Userspace pages are mapped using a different domain number from the kernel and IO mappings. If we switch the user domain to "no access" when we enter the kernel, we can prevent the kernel from touching userspace. However, the kernel needs to be able to access userspace via the various user accessor functions. With the wrapping in the previous patch, we can temporarily enable access when the kernel needs user access, and re-disable it afterwards. This allows us to trap non-intended accesses to userspace, eg, caused by an inadvertent dereference of the LIST_POISON* values, which, with appropriate user mappings setup, can be made to succeed. This in turn can allow use-after-free bugs to be further exploited than would otherwise be possible. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-03-29ARM: 8322/1: keep .text and .fixup regions closer togetherArd Biesheuvel
This moves all fixup snippets to the .text.fixup section, which is a special section that gets emitted along with the .text section for each input object file, i.e., the snippets are kept much closer to the code they refer to, which helps prevent linker failure on large kernels. Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-11-21ARM: convert printk(KERN_* to pr_*Russell King
Convert many (but not all) printk(KERN_* to pr_* to simplify the code. We take the opportunity to join some printk lines together so we don't split the message across several lines, and we also add a few levels to some messages which were previously missing them. Tested-by: Andrew Lunn <andrew@lunn.ch> Tested-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-09-12ARM: 8135/1: Fix in-correct barrier usage in SWP{B} emulationPunit Agrawal
According to the ARM ARMv7, explicit barriers are necessary when using synchronisation primitives such as SWP{B}. The use of these instructions does not automatically imply a barrier and any ordering requirements by the software must be explicitly expressed with the use of suitable barriers. Based on this, remove the barriers from SWP{B} emulation. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18ARM: SWP emulation: only initialise on ARMv7 CPUsRussell King
Previous CPUs do not have the ability to trap SWP instructions, so it's pointless initialising this code there. Tested-by: Tony Lindgren <tony@atomide.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-05-05arm: single_open() leaksAl Viro
Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-29arm: Don't use create_proc_read_entry()David Howells
Don't use create_proc_read_entry() as that is deprecated, but rather use proc_create_data() and seq_file instead. Signed-off-by: David Howells <dhowells@redhat.com> cc: Russell King <linux@arm.linux.org.uk> cc: Kevin Hilman <khilman@deeprootsystems.com> cc: Tony Lindgren <tony@atomide.com> cc: linux-arm-kernel@lists.infradead.org cc: linux-omap@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-09get rid of a bunch of open-coded create_proc_read_entry()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20ARM: missing ->mmap_sem around find_vma() in swp_emulate.cAl Viro
find_vma() is *not* safe when somebody else is removing vmas. Not just the return value might get bogus just as you are getting it (this instance doesn't try to dereference the resulting vma), the search itself can get buggered in rather spectacular ways. IOW, ->mmap_sem really, really is not optional here. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-13ARM: 7208/1: Add condition code checking to SWP emulation handler.Leif Lindholm
This patch fixes two separate issues with the SWP emulation handler: 1: Certain processors implementing ARMv7-A can (legally) take an undef exception even when the condition code would have meant that the instruction should not have been executed. 2: Opcodes with all flags set (condition code = 0xf) have been reused in recent, and not-so-recent, versions of the ARM architecture to implement unconditional extensions to the instruction set. The existing code would still have processed any undefs triggered by executing an opcode with such a value. This patch uses the new generic ARM instruction set condition code checks to implement proper handling of these situations. Signed-off-by: Leif Lindholm <leif.lindholm@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-01perf: Remove the nmi parameter from the swevent and overflow interfacePeter Zijlstra
The nmi parameter indicated if we could do wakeups from the current context, if not, we would set some state and self-IPI and let the resulting interrupt do the wakeup. For the various event classes: - hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from the PMI-tail (ARM etc.) - tracepoint: nmi=0; since tracepoint could be from NMI context. - software: nmi=[0,1]; some, like the schedule thing cannot perform wakeups, and hence need 0. As one can see, there is very little nmi=1 usage, and the down-side of not using it is that on some platforms some software events can have a jiffy delay in wakeup (when arch_irq_work_raise isn't implemented). The up-side however is that we can remove the nmi parameter and save a bunch of conditionals in fast paths. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Michael Cree <mcree@orcon.net.nz> Cc: Will Deacon <will.deacon@arm.com> Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com> Cc: Anton Blanchard <anton@samba.org> Cc: Eric B Munson <emunson@mgebm.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: David S. Miller <davem@davemloft.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Don Zickus <dzickus@redhat.com> Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-31Fix common misspellingsLucas De Marchi
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2010-11-04ARM: 6396/1: Add SWP/SWPB emulation for ARMv7 processorsLeif Lindholm
The SWP instruction was deprecated in the ARMv6 architecture, superseded by the LDREX/STREX family of instructions for load-linked/store-conditional operations. The ARMv7 multiprocessing extensions mandate that SWP/SWPB instructions are treated as undefined from reset, with the ability to enable them through the System Control Register SW bit. This patch adds the alternative solution to emulate the SWP and SWPB instructions using LDREX/STREX sequences, and log statistics to /proc/cpu/swp_emulation. To correctly deal with copy-on-write, it also modifies cpu_v7_set_pte_ext to change the mappings to priviliged RO when user RO. Signed-off-by: Leif Lindholm <leif.lindholm@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Kirill A. Shutemov <kirill@shutemov.name> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>