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2014-03-18ARM: add uprobes supportDavid A. Long
Using Rabin Vincent's ARM uprobes patches as a base, enable uprobes support on ARM. Caveats: - Thumb is not supported Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: David A. Long <dave.long@linaro.org>
2013-11-12Merge branches 'fixes', 'mmci' and 'sa11x0' into for-nextRussell King
2013-11-07ARM: 7880/1: Clear the IT state independent of the Thumb-2 modeT.J. Purtell
The ARM architecture reference specifies that the IT state bits in the PSR must be all zeros in ARM mode or behavior is unspecified. On the Qualcomm Snapdragon S4/Krait architecture CPUs the processor continues to consider the IT state bits while in ARM mode. This makes it so that some instructions are skipped by the CPU. Signed-off-by: T.J. Purtell <tj@mobisocial.us> [rmk+kernel@arm.linux.org.uk: fixed whitespace formatting in patch] Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-10-19ARM: signal: sigreturn_codes should be endian neutral to work in BE8Victor Kamensky
In case of BE8 kernel data is in BE order whereas code stays in LE order. Move sigreturn_codes to separate .S file and use proper assembler mnemonics for these code snippets. In this case compiler will take care of proper instructions byteswaps for BE8 case. Change assumes that sufficiently Thumb-capable tools are used to build kernel. Problem was discovered during ltp testing of BE system: all rt_sig* tests failed. Tested against the same tests in both BE and LE modes. Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
2013-08-03ARM: fix nommu builds with 48be69a02 (ARM: move signal handlers into a ↵Russell King
vdso-like page) Olof reports that noMMU builds error out with: arch/arm/kernel/signal.c: In function 'setup_return': arch/arm/kernel/signal.c:413:25: error: 'mm_context_t' has no member named 'sigpage' This shows one of the evilnesses of IS_ENABLED(). Get rid of it here and replace it with #ifdef's - and as no noMMU platform can make use of sigpage, depend on CONIFG_MMU not CONFIG_ARM_MPU. Reported-by: Olof Johansson <olof@lixom.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-08-03ARM: fix a cockup in 48be69a02 (ARM: move signal handlers into a vdso-like page)Russell King
Unfortunately, I never committed the fix to a nasty oops which can occur as a result of that commit: ------------[ cut here ]------------ kernel BUG at /home/olof/work/batch/include/linux/mm.h:414! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 490 Comm: killall5 Not tainted 3.11.0-rc3-00288-gabe0308 #53 task: e90acac0 ti: e9be8000 task.ti: e9be8000 PC is at special_mapping_fault+0xa4/0xc4 LR is at __do_fault+0x68/0x48c This doesn't show up unless you do quite a bit of testing; a simple boot test does not do this, so all my nightly tests were passing fine. The reason for this is that install_special_mapping() expects the page array to stick around, and as this was only inserting one page which was stored on the kernel stack, that's why this was blowing up. Reported-by: Olof Johansson <olof@lixom.net> Tested-by: Olof Johansson <olof@lixom.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-08-01ARM: move signal handlers into a vdso-like pageRussell King
Move the signal handlers into a VDSO page rather than keeping them in the vectors page. This allows us to place them randomly within this page, and also map the page at a random location within userspace further protecting these code fragments from ROP attacks. The new VDSO page is also poisoned in the same way as the vector page. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-06-17ARM: mpu: protect the vectors page with an MPU regionJonathan Austin
Without an MMU it is possible for userspace programs to start executing code in places that they have no business executing. The MPU allows some level of protection against this. This patch protects the vectors page from access by userspace processes. Userspace tasks that dereference a null pointer are already protected by an svc at 0x0 that kills them. However when tasks use an offset from a null pointer (eg a function in a null struct) they miss this carefully placed svc and enter the exception vectors in user mode, ending up in the kernel. This patch causes programs that do this to receive a SEGV instead of happily entering the kernel in user-mode, and hence avoid a 'Bad Mode' panic. As part of this change it is necessary to make sigreturn happen via the stack when there is not an sa_restorer function. This change is invisible to userspace, and irrelevant to code compiled using a uClibc toolchain, which always uses an sa_restorer function. Because we don't get to remap the vectors in !MMU kuser_helpers are not in a defined location, and hence aren't usable. This means we don't need to worry about keeping them accessible from PL0 Signed-off-by: Jonathan Austin <jonathan.austin@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> CC: Nicolas Pitre <nico@linaro.org> CC: Catalin Marinas <catalin.marinas@arm.com>
2013-02-14arm: switch to struct ksignal * passingAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03arm: switch to generic old sigaction()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03arm: switch to generic old sigsuspendAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03arm: switch to generic sigaltstackAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-01Uninclude linux/freezer.hRichard Weinberger
This include is no longer needed. (seems to be a leftover from try_to_freeze()) Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-28ARM: 7474/1: get rid of TIF_SYSCALL_RESTARTSYSAl Viro
just let do_work_pending() return 1 on normal local restarts and -1 on those that had been caused by ERESTART_RESTARTBLOCK (and 0 is still "all done, sod off to userland now"). And let the asm glue flip scno to restart_syscall(2) one if it got negative from us... [will: resolved conflicts with audit fixes] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-28ARM: 7473/1: deal with handlerless restarts without leaving the kernelAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-28ARM: 7472/1: pull all work_pending logics into C functionAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-28ARM: 7471/1: Revert "7442/1: Revert "remove unused restart trampoline""Will Deacon
This reverts commit 3b0c06226783ffc836217eb34f7eca311b1e63f7. We no longer require the restart trampoline for syscall restarting. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-28ARM: 7470/1: Revert "7443/1: Revert "new way of handling ERESTART_RESTARTBLOCK""Will Deacon
This reverts commit 433e2f307beff8adba241646ce9108544e0c5a03. Conflicts: arch/arm/kernel/ptrace.c Reintroduce the new syscall restart handling in preparation for further patches from Al Viro. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-05ARM: 7443/1: Revert "new way of handling ERESTART_RESTARTBLOCK"Will Deacon
This reverts commit 6b5c8045ecc7e726cdaa2a9d9c8e5008050e1252. Conflicts: arch/arm/kernel/ptrace.c The new syscall restarting code can lead to problems if we take an interrupt in userspace just before restarting the svc instruction. If a signal is delivered when returning from the interrupt, the TIF_SYSCALL_RESTARTSYS will remain set and cause any syscalls executed from the signal handler to be treated as a restart of the previously interrupted system call. This includes the final sigreturn call, meaning that we may fail to exit from the signal context. Furthermore, if a system call made from the signal handler requires a restart via the restart_block, it is possible to clear the thread flag and fail to restart the originally interrupted system call. The right solution to this problem is to perform the restarting in the kernel, avoiding the possibility of handling a further signal before the restart is complete. Since we're almost at -rc6, let's revert the new method for now and aim for in-kernel restarting at a later date. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-05ARM: 7442/1: Revert "remove unused restart trampoline"Will Deacon
This reverts commit fa18484d0947b976a769d15c83c50617493c81c1. We need the restart trampoline back so that we can revert a related problematic patch 6b5c8045ecc7e726cdaa2a9d9c8e5008050e1252 ("arm: new way of handling ERESTART_RESTARTBLOCK"). Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-06-01new helper: signal_delivered()Al Viro
Does block_sigmask() + tracehook_signal_handler(); called when sigframe has been successfully built. All architectures converted to it; block_sigmask() itself is gone now (merged into this one). I'm still not too happy with the signature, but that's a separate story (IMO we need a structure that would contain signal number + siginfo + k_sigaction, so that get_signal_to_deliver() would fill one, signal_delivered(), handle_signal() and probably setup...frame() - take one). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from setAl Viro
Only 3 out of 63 do not. Renamed the current variant to __set_current_blocked(), added set_current_blocked() that will exclude unblockable signals, switched open-coded instances to it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01pull clearing RESTORE_SIGMASK into block_sigmask()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01new helper: sigmask_to_save()Al Viro
replace boilerplate "should we use ->saved_sigmask or ->blocked?" with calls of obvious inlined helper... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01new helper: restore_saved_sigmask()Al Viro
first fruits of ..._restore_sigmask() helpers: now we can take boilerplate "signal didn't have a handler, clear RESTORE_SIGMASK and restore the blocked mask from ->saved_mask" into a common helper. Open-coded instances switched... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-31Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull second pile of signal handling patches from Al Viro: "This one is just task_work_add() series + remaining prereqs for it. There probably will be another pull request from that tree this cycle - at least for helpers, to get them out of the way for per-arch fixes remaining in the tree." Fix trivial conflict in kernel/irq/manage.c: the merge of Andrew's pile had brought in commit 97fd75b7b8e0 ("kernel/irq/manage.c: use the pr_foo() infrastructure to prefix printks") which changed one of the pr_err() calls that this merge moves around. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: keys: kill task_struct->replacement_session_keyring keys: kill the dummy key_replace_session_keyring() keys: change keyctl_session_to_parent() to use task_work_add() genirq: reimplement exit_irq_thread() hook via task_work_add() task_work_add: generic process-context callbacks avr32: missed _TIF_NOTIFY_RESUME on one of do_notify_resume callers parisc: need to check NOTIFY_RESUME when exiting from syscall move key_repace_session_keyring() into tracehook_notify_resume() TIF_NOTIFY_RESUME is defined on all targets now
2012-05-29Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-armLinus Torvalds
Pull arm updates from Russell King: "This contains both some fixes found when trying to get the Assabet+neponset setup as a replacement firewall with a 3c589 PCMCIA card, and a bunch of changes from Al to fix up the ARM signal handling, particularly some of the restart behaviour." * 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: ARM: neponset: make sure neponset_ncr_frob() is exported ARM: fix out[bwl]() arm: don't open-code ptrace_report_syscall() arm: bury unused _TIF_RESTORE_SIGMASK arm: remove unused restart trampoline arm: new way of handling ERESTART_RESTARTBLOCK arm: if we get into work_pending while returning to kernel mode, just go away arm: don't call try_to_freeze() from do_signal() arm: if there's no handler we need to restore sigmask, syscall or no syscall arm: trim _TIF_WORK_MASK, get rid of useless test and branch... arm: missing checks of __get_user()/__put_user() return values
2012-05-29Merge branch 'for-arm' of ↵Russell King
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal.git into for-linus Conflicts: arch/arm/kernel/ptrace.c
2012-05-23move key_repace_session_keyring() into tracehook_notify_resume()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21new helper: sigsuspend()Al Viro
guts of saved_sigmask-based sigsuspend/rt_sigsuspend. Takes kernel sigset_t *. Open-coded instances replaced with calling it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21arm: remove unused restart trampolineAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21arm: new way of handling ERESTART_RESTARTBLOCKAl Viro
new "syscall start" flag; handled in syscall_trace() by switching syscall number to that of syscall_restart(2). Restarts of that kind (ERESTART_RESTARTBLOCK) are handled by setting that bit; syscall number is not modified until the actual call. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21arm: if we get into work_pending while returning to kernel mode, just go awayAl Viro
checking in do_signal() is pointless - if we get there with !user_mode(regs) (and we might), we'll end up looping indefinitely. Check in work_pending and break out of the loop if so. Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21arm: don't call try_to_freeze() from do_signal()Al Viro
get_signal_to_deliver() will handle it itself Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21arm: if there's no handler we need to restore sigmask, syscall or no syscallAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21arm: missing checks of __get_user()/__put_user() return valuesAl Viro
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21Merge branch 'misc' into for-linusRussell King
Conflicts: arch/arm/kernel/ptrace.c
2012-04-25ARM: 7374/1: add TRACEHOOK supportWade Farnsworth
Add calls to tracehook_report_syscall_{entry,exit} and tracehook_signal_handler Signed-off-by: Steven Walter <stevenrwalter@gmail.com> Signed-off-by: Wade Farnsworth <wade_farnsworth@mentor.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-04-23ARM: 7399/1: vfp: move user vfp state save/restore code out of signal.cWill Deacon
The user VFP state must be preserved (subject to ucontext modifications) across invocation of a signal handler and this is currently handled by vfp_{preserve,restore}_context in signal.c Since this code requires intimate low-level knowledge of the VFP state, this patch moves it into vfpmodule.c. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-03-29Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-armLinus Torvalds
Pull more ARM updates from Russell King. This got a fair number of conflicts with the <asm/system.h> split, but also with some other sparse-irq and header file include cleanups. They all looked pretty trivial, though. * 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (59 commits) ARM: fix Kconfig warning for HAVE_BPF_JIT ARM: 7361/1: provide XIP_VIRT_ADDR for no-MMU builds ARM: 7349/1: integrator: convert to sparse irqs ARM: 7259/3: net: JIT compiler for packet filters ARM: 7334/1: add jump label support ARM: 7333/2: jump label: detect %c support for ARM ARM: 7338/1: add support for early console output via semihosting ARM: use set_current_blocked() and block_sigmask() ARM: exec: remove redundant set_fs(USER_DS) ARM: 7332/1: extract out code patch function from kprobes ARM: 7331/1: extract out insn generation code from ftrace ARM: 7330/1: ftrace: use canonical Thumb-2 wide instruction format ARM: 7351/1: ftrace: remove useless memory checks ARM: 7316/1: kexec: EOI active and mask all interrupts in kexec crash path ARM: Versatile Express: add NO_IOPORT ARM: get rid of asm/irq.h in asm/prom.h ARM: 7319/1: Print debug info for SIGBUS in user faults ARM: 7318/1: gic: refactor irq_start assignment ARM: 7317/1: irq: avoid NULL check in for_each_irq_desc loop ARM: 7315/1: perf: add support for the Cortex-A7 PMU ...
2012-03-24ARM: use set_current_blocked() and block_sigmask()Matt Fleming
As described in e6fa16ab ("signal: sigprocmask() should do retarget_shared_pending()") the modification of current->blocked is incorrect as we need to check for shared signals we're about to block. Also, use the new helper function introduced in commit 5e6292c0f28f ("signal: add block_sigmask() for adding sigmask to current->blocked") which centralises the code for updating current->blocked after successfully delivering a signal and reduces the amount of duplicate code across architectures. In the past some architectures got this code wrong, so using this helper function should stop that from happening again. Cc: Arnd Bergmann <arnd.bergmann@linaro.org> Cc: Dave Martin <dave.martin@linaro.org> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Will Deacon <will.deacon@arm.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-02-02ARM: 7306/1: vfp: flush thread hwstate before restoring context from sigframeWill Deacon
Following execution of a signal handler, we currently restore the VFP context from the ucontext in the signal frame. This involves copying from the user stack into the current thread's vfp_hard_struct and then flushing the new data out to the hardware registers. This is problematic when using a preemptible kernel because we could be context switched whilst updating the vfp_hard_struct. If the current thread has made use of VFP since the last context switch, the VFP notifier will copy from the hardware registers into the vfp_hard_struct, overwriting any data that had been partially copied by the signal code. Disabling preemption across copy_from_user calls is a terrible idea, so instead we move the VFP thread flush *before* we update the vfp_hard_struct. Since the flushing is performed lazily, this has the effect of disabling VFP and clearing the CPU's VFP state pointer, therefore preventing the thread from being updated with stale data on the next context switch. Cc: stable <stable@vger.kernel.org> Tested-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-12ARM: 6892/1: handle ptrace requests to change PC during interrupted system callsArnd Bergmann
GDB's interrupt.exp test cases currenly fail on ARM. The problem is how do_signal handled restarting interrupted system calls: The entry.S assembler code determines that we come from a system call; and that information is passed as "syscall" parameter to do_signal. That routine then calls get_signal_to_deliver [*] and if a signal is to be delivered, calls into handle_signal. If a system call is to be restarted either after the signal handler returns, or if no handler is to be called in the first place, the PC is updated after the get_signal_to_deliver call, either in handle_signal (if we have a handler) or at the end of do_signal (otherwise). Now the problem is that during [*], the call to get_signal_to_deliver, a ptrace intercept may happen. During this intercept, the debugger may change registers, including the PC. This is done by GDB if it wants to execute an "inferior call", i.e. the execution of some code in the debugged program triggered by GDB. To this purpose, GDB will save all registers, allocate a stack frame, set up PC and arguments as appropriate for the call, and point the link register to a dummy breakpoint instruction. Once the process is restarted, it will execute the call and then trap back to the debugger, at which point GDB will restore all registers and continue original execution. This generally works fine. However, now consider what happens when GDB attempts to do exactly that while the process was interrupted during execution of a to-be- restarted system call: do_signal is called with the syscall flag set; it calls get_signal_to_deliver, at which point the debugger takes over and changes the PC to point to a completely different place. Now get_signal_to_deliver returns without a signal to deliver; but now do_signal decides it should be restarting a system call, and decrements the PC by 2 or 4 -- so it now points to 2 or 4 bytes before the function GDB wants to call -- which leads to a subsequent crash. To fix this problem, two things need to be supported: - do_signal must be able to recognize that get_signal_to_deliver changed the PC to a different location, and skip the restart-syscall sequence - once the debugger has restored all registers at the end of the inferior call sequence, do_signal must recognize that *now* it needs to restart the pending system call, even though it was now entered from a breakpoint instead of an actual svc instruction This set of issues is solved on other platforms, usually by one of two mechanisms: - The status information "do_signal is handling a system call that may need restarting" is itself carried in some register that can be accessed via ptrace. This is e.g. on Intel the "orig_eax" register; on Sparc the kernel defines a magic extra bit in the flags register for this purpose. This allows GDB to manage that state: reset it when doing an inferior call, and restore it after the call is finished. - On s390, do_signal transparently handles this problem without requiring GDB interaction, by performing system call restarting in the following way: first, adjust the PC as necessary for restarting the call. Then, call get_signal_to_deliver; and finally just continue execution at the PC. This way, if GDB does not change the PC, everything is as before. If GDB *does* change the PC, execution will simply continue there -- and once GDB restores the PC it saved at that point, it will automatically point to the *restarted* system call. (There is the minor twist how to handle system calls that do *not* need restarting -- do_signal will undo the PC change in this case, after get_signal_to_deliver has returned, and only if ptrace did not change the PC during that call.) Because there does not appear to be any obvious register to carry the syscall-restart information on ARM, we'd either have to introduce a new artificial ptrace register just for that purpose, or else handle the issue transparently like on s390. The patch below implements the second option; using this patch makes the interrupt.exp test cases pass on ARM, with no regression in the GDB test suite otherwise. Cc: patches@linaro.org Signed-off-by: Ulrich Weigand <ulrich.weigand@linaro.org> Signed-off-by: Arnd Bergmann <arnd.bergmann@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-03-16Merge branch 'misc' into develRussell King
Conflicts: arch/arm/Kconfig
2011-02-23ARM: 6668/1: ptrace: remove single-step emulation codeWill Deacon
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 <nicolas.pitre@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-21ARM: Ensure predictable endian state on signal handler entryRussell King
Ensure a predictable endian state when entering signal handlers. This avoids programs which use SETEND to momentarily switch their endian state from having their signal handlers entered with an unpredictable endian state. Cc: <stable@kernel.org> Acked-by: Dave Martin <dave.martin@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-04-14ARM: 6051/1: VFP: preserve the HW context when calling signal handlersImre Deak
From: Imre Deak <imre.deak@nokia.com> Signal handlers can use floating point, so prevent them to corrupt the main thread's VFP context. So far there were two signal stack frame formats defined based on the VFP implementation, but the user struct used for ptrace covers all posibilities, so use it for the signal stack too. Introduce also a new user struct for VFP exception registers. In this too fields not relevant to the current VFP architecture are ignored. Support to save / restore the exception registers was added by Will Deacon. Signed-off-by: Imre Deak <imre.deak@nokia.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-11-23ARM: 5793/1: ARM: Check put_user fail in do_signal when enable OABI_COMPATJean PIHET
Using OABI, the call to put_user in do_signal can fail causing the calling app to hang. The solution is to check if put_user fails and force the app to seg fault in that case. Tested with multiple sleeping apps/threads (using the nanosleep syscall) and suspend/resume. Signed-off-by: janboe <janboe.ye at gmail.com> Signed-off-by: Jean Pihet <jpihet@mvista.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-10-25ARM: Fix signal restart issues with NX and OABI compatRussell King
The signal restarting code was placed on the user stack when OABI compatibility is enabled. Unfortunately, with an EABI NX executable, this results in an attempt to run code from the non-executable stack, which segfaults the application. Fix this by placing the code in the vectors page, along side the signal return code, and directing the application to that code. Reported-by: saeed bishara <saeed.bishara@gmail.com> Tested-by: saeed bishara <saeed.bishara@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-09-14Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (257 commits) [ARM] Update mach-types ARM: 5636/1: Move vendor enum to AMBA include ARM: Fix pfn_valid() for sparse memory [ARM] orion5x: Add LaCie NAS 2Big Network support [ARM] pxa/sharpsl_pm: zaurus c3000 aka spitz: fix resume ARM: 5686/1: at91: Correct AC97 reset line in at91sam9263ek board ARM: 5640/1: This patch modifies the support of AC97 on the at91sam9263 ek board ARM: 5689/1: Update default config of HP Jornada 700-series machines ARM: 5691/1: fix cache aliasing issues between kmap() and kmap_atomic() with highmem ARM: 5688/1: ks8695_serial: disable_irq() lockup ARM: 5687/1: fix an oops with highmem ARM: 5684/1: Add nuc960 platform to w90x900 ARM: 5683/1: Add nuc950 platform to w90x900 ARM: 5682/1: Add cpu.c and dev.c and modify some files of w90p910 platform ARM: 5626/1: add suspend/resume functions to amba-pl011 serial driver ARM: 5625/1: fix hard coded 4K resource size in amba bus detection MMC: MMCI: convert realview MMC to use gpiolib ARM: 5685/1: Make MMCI driver compile without gpiolib ARM: implement highpte ARM: Show FIQ in /proc/interrupts on CONFIG_FIQ ... Fix up trivial conflict in arch/arm/kernel/signal.c. It was due to the TIF_NOTIFY_RESUME addition in commit d0420c83f ("KEYS: Extend TIF_NOTIFY_RESUME to (almost) all architectures") and follow-ups.