user/sven/linux.git/arch/tile/kernel/stack.c, branch v3.16.1

arch: tile: re-use kbasename() helper

2013-09-30T14:34:46Z

kbasename() returns the filename part of a pathname. Signed-off-by: Andy Shevchenko

tile: don't assume user privilege is zero

2013-09-03T18:45:52Z

Technically, user privilege is anything less than kernel privilege. We modify the existing user_mode() macro to have this semantic (and use it in a couple of places it wasn't being used before), and add an IS_KERNEL_EX1() macro to the assembly code as well. Signed-off-by: Chris Metcalf

tilegx: change how we find the kernel stack

2013-08-30T15:56:58Z

Previously, we used a special-purpose register (SPR_SYSTEM_SAVE_K_0) to hold the CPU number and the top of the current kernel stack by using the low bits to hold the CPU number, and using the high bits to hold the address of the page just above where we'd want the kernel stack to be. That way we could initialize a new SP when first entering the kernel by just masking the SPR value and subtracting a couple of words. However, it's actually more useful to be able to place an arbitrary kernel-top value in the SPR. This allows us to create a new stack context (e.g. for virtualization) with an arbitrary top-of-stack VA. To make this work, we now store the CPU number in the high bits, above the highest legal VA bit (42 bits in the current tilegx microarchitecture). The full 42 bits are thus available to store the top of stack value. Getting the current cpu (a relatively common operation) is still fast; it's now a shift rather than a mask. We make this change only for tilegx, since tilepro has too few SPR bits to do this, and we don't need this support on tilepro anyway. Signed-off-by: Chris Metcalf

tile: implement gettimeofday() via vDSO

2013-08-13T20:26:21Z

This change creates the framework for vDSO calls, makes the existing rt_sigreturn() mechanism use it, and adds a fast gettimeofday(). Now that we need to expose the vDSO address to userspace, we add AT_SYSINFO_EHDR to the set of aux entries provided to userspace. (You can disable any extra vDSO support by booting with vdso=0, but the rt_sigreturn vDSO page will still be provided.) Note that glibc has supported the tile vDSO since release 2.17. Signed-off-by: Chris Metcalf

tile: support CONFIG_PREEMPT

2013-08-13T20:26:01Z

This change adds support for CONFIG_PREEMPT (full kernel preemption). In addition to the core support, this change includes a number of places where we fix up uses of smp_processor_id() and per-cpu variables. I also eliminate the PAGE_HOME_HERE and PAGE_HOME_UNKNOWN values for page homing, as it turns out they weren't being used. Signed-off-by: Chris Metcalf

tile: avoid recursive backtrace faults

2013-08-13T20:04:14Z

This change adds support for avoiding recursive backtracer crashes; we haven't seen this in practice other than when things are seriously corrupt, but it may help avoid losing the root cause of a crash. Also, don't abort kernel backtracers for invalid userspace PC's. If we do, we lose the ability to backtrace through a userspace call to a bad address above PAGE_OFFSET, even though that it can be perfectly reasonable to continue the backtrace in such a case. Signed-off-by: Chris Metcalf

sched: Rename sched.c as sched/core.c in comments and Documentation

2013-06-19T10:58:42Z

Most of the stuff from kernel/sched.c was moved to kernel/sched/core.c long time back and the comments/Documentation never got updated. I figured it out when I was going through sched-domains.txt and so thought of fixing it globally. I haven't crossed check if the stuff that is referenced in sched/core.c by all these files is still present and hasn't changed as that wasn't the motive behind this patch. Signed-off-by: Viresh Kumar Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/cdff76a265326ab8d71922a1db5be599f20aad45.1370329560.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar

tile: export a handful of symbols appropriately

2013-02-08T18:20:36Z

This was shown up by running with "allmodconfig". I used EXPORT_SYMBOL() to match existing conventions in files that were already exporting symbols, or that were exported that way by other architectures, and otherwise EXPORT_SYMBOL_GPL(). Signed-off-by: Chris Metcalf

tile: avoid defining INT_MASK macro in

2013-02-04T17:53:15Z

Unfortunately, this name conflicts with a different use of the name in various places through the tree, so don't provide it for the kernel. We preserve it for userspace to avoid breaking any userspace code that relies on this definition. This fixes a number of compile errors for various drivers that are enabled by "allyesconfig". Signed-off-by: Chris Metcalf

arch/tile: various bugs in stack backtracer

2012-04-02T16:12:45Z

Fix a long-standing bug in the stack backtracer where we would print garbage to the console instead of kernel function names, if the kernel wasn't built with symbol support (e.g. mboot). Make sure to tag every line of userspace backtrace output if we actually have the mmap_sem, since that way if there's no tag, we know that it's because we couldn't trylock the semaphore. Stop doing a TLB flush and examining page tables during backtrace. Instead, just trust that __copy_from_user_inatomic() will properly fault and return a failure, which it should do in all cases. Fix a latent bug where the backtracer would directly examine a signal context in user space, rather than copying it safely to kernel memory first. This meant that a race with another thread could potentially have caused a kernel panic. Guard against unaligned sp when trying to restart backtrace at an interrupt or signal handler point in the kernel backtracer. Report kernel symbolic information for the call instruction rather than for the following instruction. We still report the actual numeric address corresponding to the instruction after the call, for the sake of consistency with the normal expectations for stack backtracers. Signed-off-by: Chris Metcalf