This ensures that we always notify context tracking that we
have exited from user space no matter how we enter the kernel.
It is similar to how arm64 handles context tracking, for example.
This allows the removal of all the exception_enter() calls that
were added in commit 49e4e15619 ("tile: support CONTEXT_TRACKING and
thus NOHZ_FULL").
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
This flag value is saved in ptregs and used to decide whether
to disable irqs when returning from the kernel. Commit 1168df528fe4
("tile: don't assume user privilege is zero") performed a bad
merge from some KVM-enabled code that had not yet been upstreamed.
The only issue with the old code is that we will read the interrupt
mask in more conditions than we need to (e.g., coming from user
space when user space has the Interrupt Critical Section bit set, or
coming from a guest kernel), which is a slow multi-cycle operation.
This change saves those few cycles in the common case.
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
The warning occurs in setup.c, where it is known that it can't be
a problem, but it's still a good idea to silence the warning.
The onstack array is converted from an s32 to a u8, which still
is plenty of range for the values being managed there.
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
This information is easily available in the backtrace data and can
be helpful when trying to figure out the backtrace, particularly
if we're early in kernel entry or late in kernel exit.
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
This change is a prerequisite change for TASK_ISOLATION but also
stands on its own for readability and maintainability. The existing
tile do_work_pending() was called in a loop from assembly on
the slow path; this change moves the loop into C code as well.
For the x86 version see commit c5c46f59e4 ("x86/entry: Add new,
comprehensible entry and exit handlers written in C").
This change exposes a pre-existing bug on the older tilepro platform;
the singlestep processing is done last, but on tilepro (unlike tilegx)
we enable interrupts while doing that processing, so we could in
theory miss a signal or other asynchronous event. A future change
could fix this by breaking the singlestep work into a "prepare"
step done in the main loop, and a "trigger" step done after exiting
the loop. Since this change is intended as purely a restructuring
change, we call out the bug explicitly now, but don't yet fix it.
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Add the arch-specific code to support jump label for TILE-Gx. This
code shares NOP instruction with ftrace, so we move it to a common
header file.
Reviewed-by: Chris Metcalf <cmetcalf@ezchip.com>
Signed-off-by: Zhigang Lu <zlu@ezchip.com>
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
It is used by kgdb, ftrace, kprobe and jump label, so we factor
this out into a helper routine.
Reviewed-by: Chris Metcalf <cmetcalf@ezchip.com>
Signed-off-by: Zhigang Lu <zlu@ezchip.com>
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Pull arch/tile bugfix from Chris Metcalf:
"This fixes a bug in 'make allmodconfig'"
* 'stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
tile: fix build failure
When building with allmodconfig the build was failing with the error:
arch/tile/kernel/usb.c:70:1: warning: data definition has no type or storage class [enabled by default]
arch/tile/kernel/usb.c:70:1: error: type defaults to 'int' in declaration of 'arch_initcall' [-Werror=implicit-int]
arch/tile/kernel/usb.c:70:1: warning: parameter names (without types) in function declaration [enabled by default]
arch/tile/kernel/usb.c:63:19: warning: 'tilegx_usb_init' defined but not used [-Wunused-function]
Include linux/module.h to resolve the build failure.
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.
Remove the argument.
Search and replace was done with coccinelle and some extra helper
scripts around it. Thanks to Julia for her help!
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Pull tile updates from Chris Metcalf:
"This includes secure computing support as well as miscellaneous minor
improvements"
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
tile: correct some typos in opcode type names
tile/vdso: emit a GNU hash as well
tile: Remove finish_arch_switch
tile: enable full SECCOMP support
tile/time: Migrate to new 'set-state' interface
Pull irq updates from Thomas Gleixner:
"This updated pull request does not contain the last few GIC related
patches which were reported to cause a regression. There is a fix
available, but I let it breed for a couple of days first.
The irq departement provides:
- new infrastructure to support non PCI based MSI interrupts
- a couple of new irq chip drivers
- the usual pile of fixlets and updates to irq chip drivers
- preparatory changes for removal of the irq argument from interrupt
flow handlers
- preparatory changes to remove IRQF_VALID"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits)
irqchip/imx-gpcv2: IMX GPCv2 driver for wakeup sources
irqchip: Add bcm2836 interrupt controller for Raspberry Pi 2
irqchip: Add documentation for the bcm2836 interrupt controller
irqchip/bcm2835: Add support for being used as a second level controller
irqchip/bcm2835: Refactor handle_IRQ() calls out of MAKE_HWIRQ
PCI: xilinx: Fix typo in function name
irqchip/gic: Ensure gic_cpu_if_up/down() programs correct GIC instance
irqchip/gic: Only allow the primary GIC to set the CPU map
PCI/MSI: pci-xgene-msi: Consolidate chained IRQ handler install/remove
unicore32/irq: Prepare puv3_gpio_handler for irq argument removal
tile/pci_gx: Prepare trio_handle_level_irq for irq argument removal
m68k/irq: Prepare irq handlers for irq argument removal
C6X/megamode-pic: Prepare megamod_irq_cascade for irq argument removal
blackfin: Prepare irq handlers for irq argument removal
arc/irq: Prepare idu_cascade_isr for irq argument removal
sparc/irq: Use access helper irq_data_get_affinity_mask()
sparc/irq: Use helper irq_data_get_irq_handler_data()
parisc/irq: Use access helper irq_data_get_affinity_mask()
mn10300/irq: Use access helper irq_data_get_affinity_mask()
irqchip/i8259: Prepare i8259_irq_dispatch for irq argument removal
...
Pull scheduler updates from Ingo Molnar:
"The biggest change in this cycle is the rewrite of the main SMP load
balancing metric: the CPU load/utilization. The main goal was to make
the metric more precise and more representative - see the changelog of
this commit for the gory details:
9d89c257df ("sched/fair: Rewrite runnable load and utilization average tracking")
It is done in a way that significantly reduces complexity of the code:
5 files changed, 249 insertions(+), 494 deletions(-)
and the performance testing results are encouraging. Nevertheless we
need to keep an eye on potential regressions, since this potentially
affects every SMP workload in existence.
This work comes from Yuyang Du.
Other changes:
- SCHED_DL updates. (Andrea Parri)
- Simplify architecture callbacks by removing finish_arch_switch().
(Peter Zijlstra et al)
- cputime accounting: guarantee stime + utime == rtime. (Peter
Zijlstra)
- optimize idle CPU wakeups some more - inspired by Facebook server
loads. (Mike Galbraith)
- stop_machine fixes and updates. (Oleg Nesterov)
- Introduce the 'trace_sched_waking' tracepoint. (Peter Zijlstra)
- sched/numa tweaks. (Srikar Dronamraju)
- misc fixes and small cleanups"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
sched/deadline: Fix comment in enqueue_task_dl()
sched/deadline: Fix comment in push_dl_tasks()
sched: Change the sched_class::set_cpus_allowed() calling context
sched: Make sched_class::set_cpus_allowed() unconditional
sched: Fix a race between __kthread_bind() and sched_setaffinity()
sched: Ensure a task has a non-normalized vruntime when returning back to CFS
sched/numa: Fix NUMA_DIRECT topology identification
tile: Reorganize _switch_to()
sched, sparc32: Update scheduler comments in copy_thread()
sched: Remove finish_arch_switch()
sched, tile: Remove finish_arch_switch
sched, sh: Fold finish_arch_switch() into switch_to()
sched, score: Remove finish_arch_switch()
sched, avr32: Remove finish_arch_switch()
sched, MIPS: Get rid of finish_arch_switch()
sched, arm: Remove finish_arch_switch()
sched/fair: Clean up load average references
sched/fair: Provide runnable_load_avg back to cfs_rq
sched/fair: Remove task and group entity load when they are dead
sched/fair: Init cfs_rq's sched_entity load average
...
Pull driver core updates from Greg KH:
"Here is the new patches for the driver core / sysfs for 4.3-rc1.
Very small number of changes here, all the details are in the
shortlog, nothing major happening at all this kernel release, which is
nice to see"
* tag 'driver-core-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
bus: subsys: update return type of ->remove_dev() to void
driver core: correct device's shutdown order
driver core: fix docbook for device_private.device
selftests: firmware: skip timeout checks for kernels without user mode helper
kernel, cpu: Remove bogus __ref annotations
cpu: Remove bogus __ref annotation of cpu_subsys_online()
firmware: fix wrong memory deallocation in fw_add_devm_name()
sysfs.txt: update show method notes about sprintf/snprintf/scnprintf usage
devres: fix devres_get()
This function can leak kernel stack data when the user siginfo_t has a
positive si_code value. The top 16 bits of si_code descibe which fields
in the siginfo_t union are active, but they are treated inconsistently
between copy_siginfo_from_user32, copy_siginfo_to_user32 and
copy_siginfo_to_user.
copy_siginfo_from_user32 is called from rt_sigqueueinfo and
rt_tgsigqueueinfo in which the user has full control overthe top 16 bits
of si_code.
This fixes the following information leaks:
x86: 8 bytes leaked when sending a signal from a 32-bit process to
itself. This leak grows to 16 bytes if the process uses x32.
(si_code = __SI_CHLD)
x86: 100 bytes leaked when sending a signal from a 32-bit process to
a 64-bit process. (si_code = -1)
sparc: 4 bytes leaked when sending a signal from a 32-bit process to a
64-bit process. (si_code = any)
parsic and s390 have similar bugs, but they are not vulnerable because
rt_[tg]sigqueueinfo have checks that prevent sending a positive si_code
to a different process. These bugs are also fixed for consistency.
Signed-off-by: Amanieu d'Antras <amanieu@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Its return value is not used by the subsys core and nothing meaningful
can be done with it, even if we want to use it. The subsys device is
anyway getting removed.
Update prototype of ->remove_dev() to make its return type as void. Fix
all usage sites as well.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move the simulator bits into switch_to() and use
finish_arch_post_lock_switch() for the homecache migration bits.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
The irq argument of most interrupt flow handlers is unused or merily
used instead of a local variable. The handlers which need the irq
argument can retrieve the irq number from the irq descriptor.
Search and update was done with coccinelle and the invaluable help of
Julia Lawall.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Migrate tile driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.
This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Christoph Hellwig
Chris Metcalf
Zhigang Lu
Peter Zijlstra
Linus Torvalds
Sudip Mukherjee
Thomas Gleixner
Amanieu d'Antras
Viresh Kumar