kernel.git/arch/arm/include/asm/thread_info.h, branch linux-3.17.y

ARM: 8226/1: cacheflush: get rid of restarting block

2014-12-06T23:57:29Z

commit 3f4aa45ceea5789a4aade536acc27f2e0d3da5e1 upstream. We cannot restart cacheflush safely if a process provides user-defined signal handler and signal is pending. In this case -EINTR is returned and it is expected that process re-invokes syscall. However, there are a few problems with that: * looks like nobody bothers checking return value from cacheflush * but if it did, we don't provide the restart address for that, so the process has to use the same range again * ...and again, what might lead to looping forever So, remove cacheflush restarting code and terminate cache flushing as early as fatal signal is pending. Reported-by: Chanho Min Signed-off-by: Vladimir Murzin Acked-by: Will Deacon Signed-off-by: Russell King Signed-off-by: Greg Kroah-Hartman

ARM: 8078/1: get rid of hardcoded assumptions about kernel stack size

2014-07-01T14:05:47Z

Changing kernel stack size on arm is not as simple as it should be: 1) THREAD_SIZE macro doesn't respect PAGE_SIZE and THREAD_SIZE_ORDER 2) stack size is hardcoded in get_thread_info macro This patch fixes it by calculating THREAD_SIZE and thread_info address taking into account PAGE_SIZE and THREAD_SIZE_ORDER. Now changing stack size becomes simply changing THREAD_SIZE_ORDER. Signed-off-by: Andrey Ryabinin Acked-by: Nicolas Pitre Signed-off-by: Russell King

ARM: 8069/1: Make thread_save_fp macro aware of THUMB2 mode

2014-06-17T13:47:36Z

The thread_save_fp macro has been defined so that it always reads the fp member of the cpu_context_save struct. However, in the case of THUMB2 the fp is saved not in the fp (r11) member but rather in r7. This patch changes the way the macro is defined such that FP is read from the correct place depending on whether we are a THUMB2 kernel or not. This enables the backtrace in sitaution such as "echo t > /proc/sysrq-trigger" or the function in which a process sleeping when "ps -Al" is invoked. Signed-off-by: Nikolay Borisov Reviewed-by: Anurag Aggarwal Acked-by: Will Deacon Signed-off-by: Russell King

ARM: add uprobes support

2014-03-18T20:39:40Z

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 Signed-off-by: David A. Long

preempt: Make PREEMPT_ACTIVE generic

2013-11-13T19:21:47Z

No point in having this bit defined by architecture. Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20130917183629.090698799@linutronix.de

Merge branch 'for-rmk/cacheflush-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into devel-stable

2013-08-28T17:38:40Z

ARM: cacheflush: split user cache-flushing into interruptible chunks

2013-08-20T10:54:53Z

Flushing a large, non-faulting VMA from userspace can potentially result in a long time spent flushing the cache line-by-line without preemption occurring (in the case of CONFIG_PREEMPT=n). Whilst this doesn't affect the stability of the system, it can certainly affect the responsiveness and CPU availability for other tasks. This patch splits up the user cacheflush code so that it flushes in chunks of a page. After each chunk has been flushed, we may reschedule if appropriate and, before processing the next chunk, we allow any pending signals to be handled before resuming from where we left off. Signed-off-by: Will Deacon

ARM: 7790/1: Fix deferred mm switch on VIVT processors

2013-07-26T11:02:09Z

As of commit b9d4d42ad9 (ARM: Remove __ARCH_WANT_INTERRUPTS_ON_CTXSW on pre-ARMv6 CPUs), the mm switching on VIVT processors is done in the finish_arch_post_lock_switch() function to avoid whole cache flushing with interrupts disabled. The need for deferred mm switch is stored as a thread flag (TIF_SWITCH_MM). However, with preemption enabled, we can have another thread switch before finish_arch_post_lock_switch(). If the new thread has the same mm as the previous 'next' thread, the scheduler will not call switch_mm() and the TIF_SWITCH_MM flag won't be set for the new thread. This patch moves the switch pending flag to the mm_context_t structure since this is specific to the mm rather than thread. Signed-off-by: Catalin Marinas Reported-by: Marc Kleine-Budde Tested-by: Marc Kleine-Budde Cc: # 3.5+ Signed-off-by: Russell King

ARM: 7735/2: Preserve the user r/w register TPIDRURW on context switch and fork

2013-06-24T14:21:59Z

Since commit 6a1c53124aa1 the user writeable TLS register was zeroed to prevent it from being used as a covert channel between two tasks. There are more and more applications coming to Windows RT, Wine could support them, but mostly they expect to have the thread environment block (TEB) in TPIDRURW. This patch preserves that register per thread instead of clearing it. Unlike the TPIDRURO, which is already switched, the TPIDRURW can be updated from userspace so needs careful treatment in the case that we modify TPIDRURW and call fork(). To avoid this we must always read TPIDRURW in copy_thread. Signed-off-by: André Hentschel Signed-off-by: Will Deacon Signed-off-by: Jonathan Austin Signed-off-by: Russell King

ARM: 7688/1: add support for context tracking subsystem

2013-04-03T16:00:01Z

commit 91d1aa43 (context_tracking: New context tracking susbsystem) generalized parts of the RCU userspace extended quiescent state into the context tracking subsystem. Context tracking is then used to implement adaptive tickless (a.k.a extended nohz) To support the new context tracking subsystem on ARM, the user/kernel boundary transtions need to be instrumented. For exceptions and IRQs in usermode, the existing usr_entry macro is used to instrument the user->kernel transition. For the return to usermode path, the ret_to_user* path is instrumented. Using the usr_entry macro, this covers interrupts in userspace, data abort and prefetch abort exceptions in userspace as well as undefined exceptions in userspace (which is where FP emulation and VFP are handled.) For syscalls, the slow return path is covered by instrumenting the ret_to_user path. In addition, the syscall entry point is instrumented which covers the user->kernel transition for both fast and slow syscalls, and an additional instrumentation point is added for the fast syscall return path (ret_fast_syscall). Cc: Mats Liljegren Cc: Frederic Weisbecker Signed-off-by: Kevin Hilman Signed-off-by: Russell King