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path: root/arch/arm/kernel/swp_emulate.c
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2017-03-02sched/headers: Prepare to remove the <linux/mm_types.h> dependency from ↵Ingo Molnar1-0/+1
<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 Torvalds1-1/+1
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 Wang1-3/+3
__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 King1-0/+3
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>
2015-03-30ARM: 8322/1: keep .text and .fixup regions closer togetherArd Biesheuvel1-1/+1
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 King1-1/+1
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 Agrawal1-15/+0
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 King1-0/+4
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 Viro1-1/+1
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 Howells1-23/+19
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 Viro1-3/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20ARM: missing ->mmap_sem around find_vma() in swp_emulate.cAl Viro1-0/+2
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 Lindholm1-0/+16
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 Zijlstra1-1/+1
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 Marchi1-1/+1
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 Lindholm1-0/+267
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>