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* ARM: 7443/1: Revert "new way of handling ERESTART_RESTARTBLOCK"Will Deacon2012-07-051-6/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* ARM: 7442/1: Revert "remove unused restart trampoline"Will Deacon2012-07-051-0/+13
| | | | | | | | | | | | 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>
* new helper: signal_delivered()Al Viro2012-06-011-6/+1
| | | | | | | | | | | | | | 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>
* most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from setAl Viro2012-06-011-5/+1
| | | | | | | | 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>
* pull clearing RESTORE_SIGMASK into block_sigmask()Al Viro2012-06-011-15/+3
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* new helper: sigmask_to_save()Al Viro2012-06-011-9/+3
| | | | | | | 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>
* new helper: restore_saved_sigmask()Al Viro2012-06-011-5/+1
| | | | | | | | | 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>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-05-311-2/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * move key_repace_session_keyring() into tracehook_notify_resume()Al Viro2012-05-231-2/+0
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-armLinus Torvalds2012-05-291-67/+18
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * Merge branch 'for-arm' of ↵Russell King2012-05-291-67/+18
| |\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal.git into for-linus Conflicts: arch/arm/kernel/ptrace.c
| | * arm: remove unused restart trampolineAl Viro2012-05-211-13/+0
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * arm: new way of handling ERESTART_RESTARTBLOCKAl Viro2012-05-211-27/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * arm: if we get into work_pending while returning to kernel mode, just go awayAl Viro2012-05-211-9/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * arm: don't call try_to_freeze() from do_signal()Al Viro2012-05-211-4/+0
| | | | | | | | | | | | | | | | | | get_signal_to_deliver() will handle it itself Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * arm: if there's no handler we need to restore sigmask, syscall or no syscallAl Viro2012-05-211-8/+6
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * arm: missing checks of __get_user()/__put_user() return valuesAl Viro2012-05-211-6/+6
| | | | | | | | | | | | | | | Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | new helper: sigsuspend()Al Viro2012-05-211-10/+1
|/ / | | | | | | | | | | | | | | | | 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>
* | Merge branch 'misc' into for-linusRussell King2012-05-211-0/+2
|\ \ | |/ |/| | | | | Conflicts: arch/arm/kernel/ptrace.c
| * ARM: 7374/1: add TRACEHOOK supportWade Farnsworth2012-04-251-0/+2
| | | | | | | | | | | | | | | | | | 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>
* | ARM: 7399/1: vfp: move user vfp state save/restore code out of signal.cWill Deacon2012-04-231-51/+4
|/ | | | | | | | | | | | 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>
* Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-armLinus Torvalds2012-03-291-16/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * ARM: use set_current_blocked() and block_sigmask()Matt Fleming2012-03-241-16/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | ARM: 7306/1: vfp: flush thread hwstate before restoring context from sigframeWill Deacon2012-02-021-3/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | 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>
* ARM: 6892/1: handle ptrace requests to change PC during interrupted system callsArnd Bergmann2011-05-121-37/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Merge branch 'misc' into develRussell King2011-03-161-9/+0
|\ | | | | | | | | Conflicts: arch/arm/Kconfig
| * ARM: 6668/1: ptrace: remove single-step emulation codeWill Deacon2011-02-231-9/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | ARM: Ensure predictable endian state on signal handler entryRussell King2011-02-211-1/+3
|/ | | | | | | | | | | 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>
* ARM: 6051/1: VFP: preserve the HW context when calling signal handlersImre Deak2010-04-141-4/+89
| | | | | | | | | | | | | | | | | | | | | 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>
* ARM: 5793/1: ARM: Check put_user fail in do_signal when enable OABI_COMPATJean PIHET2009-11-231-2/+6
| | | | | | | | | | | | | | | 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>
* ARM: Fix signal restart issues with NX and OABI compatRussell King2009-10-251-24/+17
| | | | | | | | | | | | | | 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>
* Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds2009-09-141-49/+37
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * '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.
| * Merge branch 'master' into develRussell King2009-09-121-2/+2
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| * | ARM: 5677/1: ARM support for TIF_RESTORE_SIGMASK/pselect6/ppoll/epoll_pwaitMikael Pettersson2009-08-151-49/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds support for TIF_RESTORE_SIGMASK to ARM's signal handling, which allows to hook up the pselect6, ppoll, and epoll_pwait syscalls on ARM. Tested here with eabi userspace and a test program with a deliberate race between a child's exit and the parent's sigprocmask/select sequence. Using sys_pselect6() instead of sigprocmask/select reliably prevents the race. The other arch's support for TIF_RESTORE_SIGMASK has evolved over time: In 2.6.16: - add TIF_RESTORE_SIGMASK which parallels TIF_SIGPENDING - test both when checking for pending signal [changed later] - reimplement sys_sigsuspend() to use current->saved_sigmask, TIF_RESTORE_SIGMASK [changed later], and -ERESTARTNOHAND; ditto for sys_rt_sigsuspend(), but drop private code and use common code via __ARCH_WANT_SYS_RT_SIGSUSPEND; - there are now no "extra" calls to do_signal() so its oldset parameter is always &current->blocked so need not be passed, also its return value is changed to void - change handle_signal() to return 0/-errno - change do_signal() to honor TIF_RESTORE_SIGMASK: + get oldset from current->saved_sigmask if TIF_RESTORE_SIGMASK is set + if handle_signal() was successful then clear TIF_RESTORE_SIGMASK + if no signal was delivered and TIF_RESTORE_SIGMASK is set then clear it and restore the sigmask - hook up sys_pselect6() and sys_ppoll() In 2.6.19: - hook up sys_epoll_pwait() In 2.6.26: - allow archs to override how TIF_RESTORE_SIGMASK is implemented; default set_restore_sigmask() sets both TIF_RESTORE_SIGMASK and TIF_SIGPENDING; archs need now just test TIF_SIGPENDING again when checking for pending signal work; some archs now implement TIF_RESTORE_SIGMASK as a secondary/non-atomic thread flag bit - call set_restore_sigmask() in sys_sigsuspend() instead of setting TIF_RESTORE_SIGMASK In 2.6.29-rc: - kill sys_pselect7() which no arch wanted So for 2.6.31-rc6/ARM this patch does the following: - Add TIF_RESTORE_SIGMASK. Use the generic set_restore_sigmask() which sets both TIF_SIGPENDING and TIF_RESTORE_SIGMASK, so TIF_RESTORE_SIGMASK need not claim one of the scarce low thread flags, and existing TIF_SIGPENDING and _TIF_WORK_MASK tests need not be extended for TIF_RESTORE_SIGMASK. - sys_sigsuspend() is reimplemented to use current->saved_sigmask and set_restore_sigmask(), making it identical to most other archs - The private code for sys_rt_sigsuspend() is removed, instead generic code supplies it via __ARCH_WANT_SYS_RT_SIGSUSPEND. - sys_sigsuspend() and sys_rt_sigsuspend() no longer need a pt_regs parameter, so their assembly code wrappers are removed. - handle_signal() is changed to return 0 on success or -errno. - The oldset parameter to do_signal() is now redundant and removed, and the return value is now also redundant and changed to void. - do_signal() is changed to honor TIF_RESTORE_SIGMASK: + get oldset from current->saved_sigmask if TIF_RESTORE_SIGMASK is set + if handle_signal() was successful then clear TIF_RESTORE_SIGMASK + if no signal was delivered and TIF_RESTORE_SIGMASK is set then clear it and restore the sigmask - Hook up sys_pselect6, sys_ppoll, and sys_epoll_pwait. Signed-off-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | | KEYS: Add missing linux/tracehook.h #inclusionsDavid Howells2009-09-091-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | Add #inclusions of linux/tracehook.h to those arch files that had the tracehook call for TIF_NOTIFY_RESUME added when support for that flag was added to that arch. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | KEYS: Add a keyctl to install a process's session keyring on its parent [try #6]David Howells2009-09-021-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a keyctl to install a process's session keyring onto its parent. This replaces the parent's session keyring. Because the COW credential code does not permit one process to change another process's credentials directly, the change is deferred until userspace next starts executing again. Normally this will be after a wait*() syscall. To support this, three new security hooks have been provided: cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in the blank security creds and key_session_to_parent() - which asks the LSM if the process may replace its parent's session keyring. The replacement may only happen if the process has the same ownership details as its parent, and the process has LINK permission on the session keyring, and the session keyring is owned by the process, and the LSM permits it. Note that this requires alteration to each architecture's notify_resume path. This has been done for all arches barring blackfin, m68k* and xtensa, all of which need assembly alteration to support TIF_NOTIFY_RESUME. This allows the replacement to be performed at the point the parent process resumes userspace execution. This allows the userspace AFS pioctl emulation to fully emulate newpag() and the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to alter the parent process's PAG membership. However, since kAFS doesn't use PAGs per se, but rather dumps the keys into the session keyring, the session keyring of the parent must be replaced if, for example, VIOCSETTOK is passed the newpag flag. This can be tested with the following program: #include <stdio.h> #include <stdlib.h> #include <keyutils.h> #define KEYCTL_SESSION_TO_PARENT 18 #define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0) int main(int argc, char **argv) { key_serial_t keyring, key; long ret; keyring = keyctl_join_session_keyring(argv[1]); OSERROR(keyring, "keyctl_join_session_keyring"); key = add_key("user", "a", "b", 1, keyring); OSERROR(key, "add_key"); ret = keyctl(KEYCTL_SESSION_TO_PARENT); OSERROR(ret, "KEYCTL_SESSION_TO_PARENT"); return 0; } Compiled and linked with -lkeyutils, you should see something like: [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: _ses 355907932 --alswrv 4043 -1 \_ keyring: _uid.4043 [dhowells@andromeda ~]$ /tmp/newpag [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: _ses 1055658746 --alswrv 4043 4043 \_ user: a [dhowells@andromeda ~]$ /tmp/newpag hello [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: hello 340417692 --alswrv 4043 4043 \_ user: a Where the test program creates a new session keyring, sticks a user key named 'a' into it and then installs it on its parent. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | | KEYS: Extend TIF_NOTIFY_RESUME to (almost) all architectures [try #6]David Howells2009-09-021-0/+5
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement TIF_NOTIFY_RESUME for most of those architectures in which isn't yet available, and, whilst we're at it, have it call the appropriate tracehook. After this patch, blackfin, m68k* and xtensa still lack support and need alteration of assembly code to make it work. Resume notification can then be used (by a later patch) to install a new session keyring on the parent of a process. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> cc: linux-arch@vger.kernel.org Signed-off-by: James Morris <jmorris@namei.org>
* | ARM: 5638/1: arch/arm/kernel/signal.c: use correct address space for CRUNCHHartley Sweeten2009-08-051-2/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | preserve_crunch_context() calls __copy_to_user() which expects the destination address to be in __user space. setup_sigframe() properly passes the destination address. restore_crunch_context() calls __copy_from_user() which expects the source address to be in __user space. restore_sigframe() properly passes the source address. This fixes {preserve/restore}_crunch_context() to accept the address as __user space and resolves the following sparse warnings: arch/arm/kernel/signal.c:146:31: warning: incorrect type in argument 1 (different address spaces) expected void [noderef] <asn:1>*to got struct crunch_sigframe *frame arch/arm/kernel/signal.c:156:38: warning: incorrect type in argument 2 (different address spaces) expected void const [noderef] <asn:1>*from got struct crunch_sigframe *frame arch/arm/kernel/signal.c:250:48: warning: incorrect type in argument 1 (different address spaces) expected struct crunch_sigframe *frame got struct crunch_sigframe [noderef] <asn:1>*<noident> arch/arm/kernel/signal.c:365:49: warning: incorrect type in argument 1 (different address spaces) expected struct crunch_sigframe *frame got struct crunch_sigframe [noderef] <asn:1>*<noident> Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Merge branch 'master' of ↵David S. Miller2009-06-151-2/+6
|\ | | | | | | | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 Conflicts: Documentation/feature-removal-schedule.txt drivers/scsi/fcoe/fcoe.c net/core/drop_monitor.c net/core/net-traces.c
| * Clear the IT state when invoking a Thumb-2 signal handlerCatalin Marinas2009-05-301-2/+6
| | | | | | | | | | | | | | | | | | If a process is interrupted during an If-Then block and a signal is invoked, the ITSTATE bits must be cleared otherwise the handler would not run correctly. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Joseph S. Myers <joseph@codesourcery.com>
* | syscall: Sort out syscall_restart name clash.Eric W. Biederman2009-05-201-3/+3
|/ | | | | | | | | | | | | | | | | | | | Stephen Rothwell <sfr@canb.auug.org.au> writes: > Today's linux-next build of at least some av32 and arm configs failed like this: > > arch/avr32/kernel/signal.c:216: error: conflicting types for 'restart_syscall' > include/linux/sched.h:2184: error: previous definition of 'restart_syscall' was here > > Caused by commit 690cc3ffe33ac4a2857583c22d4c6244ae11684d ("syscall: > Implement a convinience function restart_syscall") from the net tree. Grrr. Some days it feels like all of the good names are already taken. Let's just rename the two static users in arm and avr32 to get this sorted out. Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [ARM] Convert asm/uaccess.h to linux/uaccess.hRussell King2008-09-061-1/+1
| | | | Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] 4870/1: fix signal return code when enable CONFIG_OABI_COMPATjanboe2008-03-201-2/+2
| | | | | | | fix signal return code when enable CONFIG_OABI_COMPAT Signed-off-by: Janboe Ye <janboe.ye@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] ptrace: clean up single stepping supportRussell King2007-04-211-17/+5
| | | | Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds2006-12-071-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (76 commits) [ARM] 4002/1: S3C24XX: leave parent IRQs unmasked [ARM] 4001/1: S3C24XX: shorten reboot time [ARM] 3983/2: remove unused argument to __bug() [ARM] 4000/1: Osiris: add third serial port in [ARM] 3999/1: RX3715: suspend to RAM support [ARM] 3998/1: VR1000: LED platform devices [ARM] 3995/1: iop13xx: add iop13xx support [ARM] 3968/1: iop13xx: add iop13xx_defconfig [ARM] Update mach-types [ARM] Allow gcc to optimise arm_add_memory a little more [ARM] 3991/1: i.MX/MX1 high resolution time source [ARM] 3990/1: i.MX/MX1 more precise PLL decode [ARM] 3986/1: H1940: suspend to RAM support [ARM] 3985/1: ixp4xx clocksource cleanup [ARM] 3984/1: ixp4xx/nslu2: Fix disk LED numbering (take 2) [ARM] 3994/1: ixp23xx: fix handling of pci master aborts [ARM] 3981/1: sched_clock for PXA2xx [ARM] 3980/1: extend the ARM Versatile sched_clock implementation from 32 to 63 bit [ARM] 3979/1: extend the SA11x0 sched_clock implementation from 32 to 63 bit period [ARM] 3978/1: macro to provide a 63-bit value from a 32-bit hardware counter ...
| * [ARM] Include asm/elf.h instead of asm/procinfo.hRussell King2006-11-301-0/+1
| | | | | | | | | | | | | | These files want to provide/access ELF hwcap information, so should be including asm/elf.h rather than asm/procinfo.h Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* | [PATCH] Add include/linux/freezer.h and move definitions from sched.hNigel Cunningham2006-12-071-0/+1
|/ | | | | | | | | | | | | Move process freezing functions from include/linux/sched.h to freezer.h, so that modifications to the freezer or the kernel configuration don't require recompiling just about everything. [akpm@osdl.org: fix ueagle driver] Signed-off-by: Nigel Cunningham <nigel@suspend2.net> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Remove obsolete #include <linux/config.h>Jörn Engel2006-06-301-1/+0
| | | | | Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [ARM] 3664/1: crunch: add signal frame save/restoreLennert Buytenhek2006-06-281-0/+39
| | | | | | | | | | | Patch from Lennert Buytenhek This patch makes the kernel save Crunch state in userland signal frames, so that any userland signal handler can safely use the Crunch coprocessor without corrupting the Crunch state of the code it preempted. Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Merge signal handler branchRussell King2006-06-241-125/+82
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