The members of the new struct are the required ones for the new NMI
safe accessor to clcok monotonic. In order to reuse the existing
timekeeping code and to make the update of the fast NMI safe
timekeepers a simple memcpy use the struct for the timekeeper as well
and convert all users.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
cycle_last was added to the clocksource to support the TSC
validation. We moved that to the core code, so we can get rid of the
extra copy.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
We only have to check kdump memory for the MEM_GOING_OFFLINE action.
Therefore skip the test and return NOTIFY_OK for all other memory
hotplug actions.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove check of obsolete variable function_trace_stop as requested by
Steven Rostedt.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The PSW mask check of the PTRACE_POKEUSR_AREA command is incorrect.
The PSW_MASK_USER define contains the PSW_MASK_ASC bits, the ptrace
interface accepts all combinations for the address-space-control
bits. To protect the kernel space the PSW mask check in ptrace needs
to reject the address-space-control bit combination for home space.
Fixes CVE-2014-3534
Cc: stable@vger.kernel.org
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Inlined uaccess functions require the mvcos facility (bit 27), not the tod
clock steering facility (bit 28) for z10 and newer machines.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Transition to using the new generic PERF_PMU_CAP_NO_INTERRUPT method for
failing a sampling event when no PMU interrupt is available.
Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Thomas Huth <thuth@linux.vnet.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1406150204290.16738@vincent-weaver-1.umelst.maine.edu
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The uc_sigmask definition in the kernel differs from the one in the
glibc, the kernel uc_sigmask has 64 bits while the glibc verison
is 1024 bits. The extension of the ucontext structure for 64-bit
register support for 31-bit compat processes added a new field
uc_gprs_high which starts 8 bytes after the uc_sigmask field.
As the glibc view of the ucontext assumes a size of 128 bytes for
uc_sigmask add a 120 byte padding to the kernel structure
ucontext_extended after the 8 byte uc_sigmask.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull core irq updates from Thomas Gleixner:
"The irq department delivers:
- Another tree wide update to get rid of the horrible create_irq
interface along with its even more horrible variants. That also
gets rid of the last leftovers of the initial sparse irq hackery.
arch/driver specific changes have been either acked or ignored.
- A fix for the spurious interrupt detection logic with threaded
interrupts.
- A new ARM SoC interrupt controller
- The usual pile of fixes and improvements all over the place"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
Documentation: brcmstb-l2: Add Broadcom STB Level-2 interrupt controller binding
irqchip: brcmstb-l2: Add Broadcom Set Top Box Level-2 interrupt controller
genirq: Improve documentation to match current implementation
ARM: iop13xx: fix msi support with sparse IRQ
genirq: Provide !SMP stub for irq_set_affinity_notifier()
irqchip: armada-370-xp: Move the devicetree binding documentation
irqchip: gic: Use mask field in GICC_IAR
genirq: Remove dynamic_irq mess
ia64: Use irq_init_desc
genirq: Replace dynamic_irq_init/cleanup
genirq: Remove irq_reserve_irq[s]
genirq: Replace reserve_irqs in core code
s390: Avoid call to irq_reserve_irqs()
s390: Remove pointless arch_show_interrupts()
s390: pci: Check return value of alloc_irq_desc() proper
sh: intc: Remove pointless irq_reserve_irqs() invocation
x86, irq: Remove pointless irq_reserve_irqs() call
genirq: Make create/destroy_irq() ia64 private
tile: Use SPARSE_IRQ
tile: pci: Use irq_alloc/free_hwirq()
...
was a pretty active cycle for KVM. Changes include:
- a lot of s390 changes: optimizations, support for migration,
GDB support and more
- ARM changes are pretty small: support for the PSCI 0.2 hypercall
interface on both the guest and the host (the latter acked by Catalin)
- initial POWER8 and little-endian host support
- support for running u-boot on embedded POWER targets
- pretty large changes to MIPS too, completing the userspace interface
and improving the handling of virtualized timer hardware
- for x86, a larger set of changes is scheduled for 3.17. Still,
we have a few emulator bugfixes and support for running nested
fully-virtualized Xen guests (para-virtualized Xen guests have
always worked). And some optimizations too.
The only missing architecture here is ia64. It's not a coincidence
that support for KVM on ia64 is scheduled for removal in 3.17.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm into next
Pull KVM updates from Paolo Bonzini:
"At over 200 commits, covering almost all supported architectures, this
was a pretty active cycle for KVM. Changes include:
- a lot of s390 changes: optimizations, support for migration, GDB
support and more
- ARM changes are pretty small: support for the PSCI 0.2 hypercall
interface on both the guest and the host (the latter acked by
Catalin)
- initial POWER8 and little-endian host support
- support for running u-boot on embedded POWER targets
- pretty large changes to MIPS too, completing the userspace
interface and improving the handling of virtualized timer hardware
- for x86, a larger set of changes is scheduled for 3.17. Still, we
have a few emulator bugfixes and support for running nested
fully-virtualized Xen guests (para-virtualized Xen guests have
always worked). And some optimizations too.
The only missing architecture here is ia64. It's not a coincidence
that support for KVM on ia64 is scheduled for removal in 3.17"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (203 commits)
KVM: add missing cleanup_srcu_struct
KVM: PPC: Book3S PR: Rework SLB switching code
KVM: PPC: Book3S PR: Use SLB entry 0
KVM: PPC: Book3S HV: Fix machine check delivery to guest
KVM: PPC: Book3S HV: Work around POWER8 performance monitor bugs
KVM: PPC: Book3S HV: Make sure we don't miss dirty pages
KVM: PPC: Book3S HV: Fix dirty map for hugepages
KVM: PPC: Book3S HV: Put huge-page HPTEs in rmap chain for base address
KVM: PPC: Book3S HV: Fix check for running inside guest in global_invalidates()
KVM: PPC: Book3S: Move KVM_REG_PPC_WORT to an unused register number
KVM: PPC: Book3S: Add ONE_REG register names that were missed
KVM: PPC: Add CAP to indicate hcall fixes
KVM: PPC: MPIC: Reset IRQ source private members
KVM: PPC: Graciously fail broken LE hypercalls
PPC: ePAPR: Fix hypercall on LE guest
KVM: PPC: BOOK3S: Remove open coded make_dsisr in alignment handler
KVM: PPC: BOOK3S: Always use the saved DAR value
PPC: KVM: Make NX bit available with magic page
KVM: PPC: Disable NX for old magic page using guests
KVM: PPC: BOOK3S: HV: Add mixed page-size support for guest
...
Pull scheduler updates from Ingo Molnar:
"The main scheduling related changes in this cycle were:
- various sched/numa updates, for better performance
- tree wide cleanup of open coded nice levels
- nohz fix related to rq->nr_running use
- cpuidle changes and continued consolidation to improve the
kernel/sched/idle.c high level idle scheduling logic. As part of
this effort I pulled cpuidle driver changes from Rafael as well.
- standardized idle polling amongst architectures
- continued work on preparing better power/energy aware scheduling
- sched/rt updates
- misc fixlets and cleanups"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (49 commits)
sched/numa: Decay ->wakee_flips instead of zeroing
sched/numa: Update migrate_improves/degrades_locality()
sched/numa: Allow task switch if load imbalance improves
sched/rt: Fix 'struct sched_dl_entity' and dl_task_time() comments, to match the current upstream code
sched: Consolidate open coded implementations of nice level frobbing into nice_to_rlimit() and rlimit_to_nice()
sched: Initialize rq->age_stamp on processor start
sched, nohz: Change rq->nr_running to always use wrappers
sched: Fix the rq->next_balance logic in rebalance_domains() and idle_balance()
sched: Use clamp() and clamp_val() to make sys_nice() more readable
sched: Do not zero sg->cpumask and sg->sgp->power in build_sched_groups()
sched/numa: Fix initialization of sched_domain_topology for NUMA
sched: Call select_idle_sibling() when not affine_sd
sched: Simplify return logic in sched_read_attr()
sched: Simplify return logic in sched_copy_attr()
sched: Fix exec_start/task_hot on migrated tasks
arm64: Remove TIF_POLLING_NRFLAG
metag: Remove TIF_POLLING_NRFLAG
sched/idle: Make cpuidle_idle_call() void
sched/idle: Reflow cpuidle_idle_call()
sched/idle: Delay clearing the polling bit
...
Remove the 96-byte irb array from the lowcore and create a per-cpu
variable instead. That way we will pick up any change in the definition
of the struct irb automatically.
Acked-By: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the check for the extract-cpu-time facility within early startup
code. Both kernel and user space work if the facility is not installed.
The vdso code has a run time check if the ectg is available. Besides that
there is no known user.
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With inlined uaccess functions we always need the mvcos facility.
Checking at each inline place if mvcos is available would make the
inlining of get_user/put_user pointless.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Analog to git commit 28b92e09e2
first cast tk->wall_to_monotonic.tv_nsec to u64 before doing
the shift with tk->shift to avoid loosing relevant bits on a
32-bit kernel.
Cc: stable@vger.kernel.org # 3.13+
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The oi and ni instructions used in entry[64].S to set and clear bits
in the thread-flags are not guaranteed to be atomic in regard to other
CPUs. Split the TIF bits into CPU, pt_regs and thread-info specific
bits. Updates on the TIF bits are done with atomic instructions,
updates on CPU and pt_regs bits are done with non-atomic instructions.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Always switch to the kernel ASCE in switch_mm. Load the secondary
space ASCE in finish_arch_post_lock_switch after checking that
any pending page table operations have completed. The primary
ASCE is loaded in entry[64].S. With this the update_primary_asce
call can be removed from the switch_to macro and from the start
of switch_mm function. Remove the load_primary argument from
update_user_asce/clear_user_asce, rename update_user_asce to
set_user_asce and rename update_primary_asce to load_kernel_asce.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently the smp_stop_cpu() function for SMP kernels enters a busy
loop when "begin" is entered on the z/VM console after Linux is halted.
To avoid this behavior, use the non-SMP variant of smp_stop_cpu()
which stops the CPU again after "begin" is entered. As a side
effect we now have consistent behavior for SMP and non-SMP Linux.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently there are two s390 kernel dump config options "CONFIG_ZFCPDUMP"
and "CONFIG_CRASH_DUMP". In order to keep things simple and because the
"CONFIG_ZFCPDUMP" option already has a dependency to "CONFIG_CRASH_DUMP"
remove the CONFIG_ZFCPDUMP option.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use lowcore constant to improve the code generated for spinlocks.
[ Martin Schwidefsky: patch breakdown and code beautification ]
Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The original bootmem allocator is getting replaced by memblock. To
cover the needs of the s390 kdump implementation the physical memory
list is used.
With this patch the bootmem allocator and its bitmaps are completely
removed from s390.
Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There is no need to mark the lower interrupts as reserved in order to
exclude them from dynamic allocation.
Provide arch_dynirq_lower_bound() to exclude the lower space.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Grant Likely <grant.likely@linaro.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Link: http://lkml.kernel.org/r/20140507154339.811205235@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
S390 is not using the generic show interrupts implementation so the
extra arch_show_interrupts() is just useless.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Grant Likely <grant.likely@linaro.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Link: http://lkml.kernel.org/r/20140507154339.609149081@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds fields which are currently missing but needed for the correct
injection of interrupts.
This is based on a patch by David Hildenbrand
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
per_perc_atmid is currently a two-byte field that combines two
fields, the PER code and the PER Addressing-and-Translation-Mode
Identification (ATMID)
Let's make them accessible indepently and also rename per_cause to
per_code.
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
According to the Principles of Operation, at offset 0xA3
in the lowcore we have the "Architectural-Mode identification",
not an "access identification".
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Actually this also enable sys_setattr and sys_getattr, since I forgot to
increase NR_syscalls when adding those syscalls.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
It doesn't make sense to map user space addresses to kernel symbols when
show_registers() prints a user space psw. So just skip the translation part
if a user space psw is handled.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
smp_stop_cpu() should stop the current cpu even for !CONFIG_SMP.
Otherwise machine_halt() will return and and the machine generates a
panic instread of simply stopping the current cpu:
Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000000
CPU: 0 PID: 1 Comm: systemd-shutdow Not tainted 3.14.0-01527-g2b6ef16a6bc5 #10
[...]
Call Trace:
([<0000000000110db0>] show_trace+0xf8/0x158)
[<0000000000110e7a>] show_stack+0x6a/0xe8
[<000000000074dba8>] panic+0xe4/0x268
[<0000000000140570>] do_exit+0xa88/0xb2c
[<000000000016e12c>] SyS_reboot+0x1f0/0x234
[<000000000075da70>] sysc_nr_ok+0x22/0x28
[<000000007d5a09b4>] 0x7d5a09b4
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The git commit c63badebfe
"s390: optimize control register update" broke the update for
control register 0. After the update do the lctlg from the correct
value.
Cc: <stable@vger.kernel.org> # 3.14
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull second set of s390 patches from Martin Schwidefsky:
"The second part of Heikos uaccess rework, the page table walker for
uaccess is now a thing of the past (yay!)
The code change to fix the theoretical TLB flush problem allows us to
add a TLB flush optimization for zEC12, this machine has new
instructions that allow to do CPU local TLB flushes for single pages
and for all pages of a specific address space.
Plus the usual bug fixing and some more cleanup"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/uaccess: rework uaccess code - fix locking issues
s390/mm,tlb: optimize TLB flushing for zEC12
s390/mm,tlb: safeguard against speculative TLB creation
s390/irq: Use defines for external interruption codes
s390/irq: Add defines for external interruption codes
s390/sclp: add timeout for queued requests
kvm/s390: also set guest pages back to stable on kexec/kdump
lcs: Add missing destroy_timer_on_stack()
s390/tape: Add missing destroy_timer_on_stack()
s390/tape: Use del_timer_sync()
s390/3270: fix crash with multiple reset device requests
s390/bitops,atomic: add missing memory barriers
s390/zcrypt: add length check for aligned data to avoid overflow in msg-type 6
The purpose of this single series of commits from Srivatsa S Bhat (with
a small piece from Gautham R Shenoy) touching multiple subsystems that use
CPU hotplug notifiers is to provide a way to register them that will not
lead to deadlocks with CPU online/offline operations as described in the
changelog of commit 93ae4f978c (CPU hotplug: Provide lockless versions
of callback registration functions).
The first three commits in the series introduce the API and document it
and the rest simply goes through the users of CPU hotplug notifiers and
converts them to using the new method.
/
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Merge tag 'cpu-hotplug-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull CPU hotplug notifiers registration fixes from Rafael Wysocki:
"The purpose of this single series of commits from Srivatsa S Bhat
(with a small piece from Gautham R Shenoy) touching multiple
subsystems that use CPU hotplug notifiers is to provide a way to
register them that will not lead to deadlocks with CPU online/offline
operations as described in the changelog of commit 93ae4f978c ("CPU
hotplug: Provide lockless versions of callback registration
functions").
The first three commits in the series introduce the API and document
it and the rest simply goes through the users of CPU hotplug notifiers
and converts them to using the new method"
* tag 'cpu-hotplug-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (52 commits)
net/iucv/iucv.c: Fix CPU hotplug callback registration
net/core/flow.c: Fix CPU hotplug callback registration
mm, zswap: Fix CPU hotplug callback registration
mm, vmstat: Fix CPU hotplug callback registration
profile: Fix CPU hotplug callback registration
trace, ring-buffer: Fix CPU hotplug callback registration
xen, balloon: Fix CPU hotplug callback registration
hwmon, via-cputemp: Fix CPU hotplug callback registration
hwmon, coretemp: Fix CPU hotplug callback registration
thermal, x86-pkg-temp: Fix CPU hotplug callback registration
octeon, watchdog: Fix CPU hotplug callback registration
oprofile, nmi-timer: Fix CPU hotplug callback registration
intel-idle: Fix CPU hotplug callback registration
clocksource, dummy-timer: Fix CPU hotplug callback registration
drivers/base/topology.c: Fix CPU hotplug callback registration
acpi-cpufreq: Fix CPU hotplug callback registration
zsmalloc: Fix CPU hotplug callback registration
scsi, fcoe: Fix CPU hotplug callback registration
scsi, bnx2fc: Fix CPU hotplug callback registration
scsi, bnx2i: Fix CPU hotplug callback registration
...
But there were a few features that were added.
Uprobes now work with event triggers and multi buffers.
Uprobes have support under ftrace and perf.
The big feature is that the function tracer can now be used within the
multi buffer instances. That is, you can now trace some functions
in one buffer, others in another buffer, all functions in a third buffer
and so on. They are basically agnostic from each other. This only
works for the function tracer and not for the function graph trace,
although you can have the function graph tracer running in the top level
buffer (or any tracer for that matter) and have different function tracing
going on in the sub buffers.
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Merge tag 'trace-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"Most of the changes were largely clean ups, and some documentation.
But there were a few features that were added:
Uprobes now work with event triggers and multi buffers and have
support under ftrace and perf.
The big feature is that the function tracer can now be used within the
multi buffer instances. That is, you can now trace some functions in
one buffer, others in another buffer, all functions in a third buffer
and so on. They are basically agnostic from each other. This only
works for the function tracer and not for the function graph trace,
although you can have the function graph tracer running in the top
level buffer (or any tracer for that matter) and have different
function tracing going on in the sub buffers"
* tag 'trace-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (45 commits)
tracing: Add BUG_ON when stack end location is over written
tracepoint: Remove unused API functions
Revert "tracing: Move event storage for array from macro to standalone function"
ftrace: Constify ftrace_text_reserved
tracepoints: API doc update to tracepoint_probe_register() return value
tracepoints: API doc update to data argument
ftrace: Fix compilation warning about control_ops_free
ftrace/x86: BUG when ftrace recovery fails
ftrace: Warn on error when modifying ftrace function
ftrace: Remove freelist from struct dyn_ftrace
ftrace: Do not pass data to ftrace_dyn_arch_init
ftrace: Pass retval through return in ftrace_dyn_arch_init()
ftrace: Inline the code from ftrace_dyn_table_alloc()
ftrace: Cleanup of global variables ftrace_new_pgs and ftrace_update_cnt
tracing: Evaluate len expression only once in __dynamic_array macro
tracing: Correctly expand len expressions from __dynamic_array macro
tracing/module: Replace include of tracepoint.h with jump_label.h in module.h
tracing: Fix event header migrate.h to include tracepoint.h
tracing: Fix event header writeback.h to include tracepoint.h
tracing: Warn if a tracepoint is not set via debugfs
...
The current uaccess code uses a page table walk in some circumstances,
e.g. in case of the in atomic futex operations or if running on old
hardware which doesn't support the mvcos instruction.
However it turned out that the page table walk code does not correctly
lock page tables when accessing page table entries.
In other words: a different cpu may invalidate a page table entry while
the current cpu inspects the pte. This may lead to random data corruption.
Adding correct locking however isn't trivial for all uaccess operations.
Especially copy_in_user() is problematic since that requires to hold at
least two locks, but must be protected against ABBA deadlock when a
different cpu also performs a copy_in_user() operation.
So the solution is a different approach where we change address spaces:
User space runs in primary address mode, or access register mode within
vdso code, like it currently already does.
The kernel usually also runs in home space mode, however when accessing
user space the kernel switches to primary or secondary address mode if
the mvcos instruction is not available or if a compare-and-swap (futex)
instruction on a user space address is performed.
KVM however is special, since that requires the kernel to run in home
address space while implicitly accessing user space with the sie
instruction.
So we end up with:
User space:
- runs in primary or access register mode
- cr1 contains the user asce
- cr7 contains the user asce
- cr13 contains the kernel asce
Kernel space:
- runs in home space mode
- cr1 contains the user or kernel asce
-> the kernel asce is loaded when a uaccess requires primary or
secondary address mode
- cr7 contains the user or kernel asce, (changed with set_fs())
- cr13 contains the kernel asce
In case of uaccess the kernel changes to:
- primary space mode in case of a uaccess (copy_to_user) and uses
e.g. the mvcp instruction to access user space. However the kernel
will stay in home space mode if the mvcos instruction is available
- secondary space mode in case of futex atomic operations, so that the
instructions come from primary address space and data from secondary
space
In case of kvm the kernel runs in home space mode, but cr1 gets switched
to contain the gmap asce before the sie instruction gets executed. When
the sie instruction is finished cr1 will be switched back to contain the
user asce.
A context switch between two processes will always load the kernel asce
for the next process in cr1. So the first exit to user space is a bit
more expensive (one extra load control register instruction) than before,
however keeps the code rather simple.
In sum this means there is no need to perform any error prone page table
walks anymore when accessing user space.
The patch seems to be rather large, however it mainly removes the
the page table walk code and restores the previously deleted "standard"
uaccess code, with a couple of changes.
The uaccess without mvcos mode can be enforced with the "uaccess_primary"
kernel parameter.
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The zEC12 machines introduced the local-clearing control for the IDTE
and IPTE instruction. If the control is set only the TLB of the local
CPU is cleared of entries, either all entries of a single address space
for IDTE, or the entry for a single page-table entry for IPTE.
Without the local-clearing control the TLB flush is broadcasted to all
CPUs in the configuration, which is expensive.
The reset of the bit mask of the CPUs that need flushing after a
non-local IDTE is tricky. As TLB entries for an address space remain
in the TLB even if the address space is detached a new bit field is
required to keep track of attached CPUs vs. CPUs in the need of a
flush. After a non-local flush with IDTE the bit-field of attached CPUs
is copied to the bit-field of CPUs in need of a flush. The ordering
of operations on cpu_attach_mask, attach_count and mm_cpumask(mm) is
such that an underindication in mm_cpumask(mm) is prevented but an
overindication in mm_cpumask(mm) is possible.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use the new defines for external interruption codes to get rid
of "magic" numbers in the s390 source code. And while we're at it,
also rename the (un-)register_external_interrupt function to
something shorter so that this patch does not exceed the 80
columns all over the place.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull kvm updates from Paolo Bonzini:
"PPC and ARM do not have much going on this time. Most of the cool
stuff, instead, is in s390 and (after a few releases) x86.
ARM has some caching fixes and PPC has transactional memory support in
guests. MIPS has some fixes, with more probably coming in 3.16 as
QEMU will soon get support for MIPS KVM.
For x86 there are optimizations for debug registers, which trigger on
some Windows games, and other important fixes for Windows guests. We
now expose to the guest Broadwell instruction set extensions and also
Intel MPX. There's also a fix/workaround for OS X guests, nested
virtualization features (preemption timer), and a couple kvmclock
refinements.
For s390, the main news is asynchronous page faults, together with
improvements to IRQs (floating irqs and adapter irqs) that speed up
virtio devices"
* tag 'kvm-3.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (96 commits)
KVM: PPC: Book3S HV: Save/restore host PMU registers that are new in POWER8
KVM: PPC: Book3S HV: Fix decrementer timeouts with non-zero TB offset
KVM: PPC: Book3S HV: Don't use kvm_memslots() in real mode
KVM: PPC: Book3S HV: Return ENODEV error rather than EIO
KVM: PPC: Book3S: Trim top 4 bits of physical address in RTAS code
KVM: PPC: Book3S HV: Add get/set_one_reg for new TM state
KVM: PPC: Book3S HV: Add transactional memory support
KVM: Specify byte order for KVM_EXIT_MMIO
KVM: vmx: fix MPX detection
KVM: PPC: Book3S HV: Fix KVM hang with CONFIG_KVM_XICS=n
KVM: PPC: Book3S: Introduce hypervisor call H_GET_TCE
KVM: PPC: Book3S HV: Fix incorrect userspace exit on ioeventfd write
KVM: s390: clear local interrupts at cpu initial reset
KVM: s390: Fix possible memory leak in SIGP functions
KVM: s390: fix calculation of idle_mask array size
KVM: s390: randomize sca address
KVM: ioapic: reinject pending interrupts on KVM_SET_IRQCHIP
KVM: Bump KVM_MAX_IRQ_ROUTES for s390
KVM: s390: irq routing for adapter interrupts.
KVM: s390: adapter interrupt sources
...
Pull irq code updates from Thomas Gleixner:
"The irq department proudly presents:
- Another tree wide sweep of irq infrastructure abuse. Clear winner
of the trainwreck engineering contest was:
#include "../../../kernel/irq/settings.h"
- Tree wide update of irq_set_affinity() callbacks which miss a cpu
online check when picking a single cpu out of the affinity mask.
- Tree wide consolidation of interrupt statistics.
- Updates to the threaded interrupt infrastructure to allow explicit
wakeup of the interrupt thread and a variant of synchronize_irq()
which synchronizes only the hard interrupt handler. Both are
needed to replace the homebrewn thread handling in the mmc/sdhci
code.
- New irq chip callbacks to allow proper support for GPIO based irqs.
The GPIO based interrupts need to request/release GPIO resources
from request/free_irq.
- A few new ARM interrupt chips. No revolutionary new hardware, just
differently wreckaged variations of the scheme.
- Small improvments, cleanups and updates all over the place"
I was hoping that that trainwreck engineering contest was a April Fools'
joke. But no.
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (68 commits)
irqchip: sun7i/sun6i: Disable NMI before registering the handler
ARM: sun7i/sun6i: dts: Fix IRQ number for sun6i NMI controller
ARM: sun7i/sun6i: irqchip: Update the documentation
ARM: sun7i/sun6i: dts: Add NMI irqchip support
ARM: sun7i/sun6i: irqchip: Add irqchip driver for NMI controller
genirq: Export symbol no_action()
arm: omap: Fix typo in ams-delta-fiq.c
m68k: atari: Fix the last kernel_stat.h fallout
irqchip: sun4i: Simplify sun4i_irq_ack
irqchip: sun4i: Use handle_fasteoi_irq for all interrupts
genirq: procfs: Make smp_affinity values go+r
softirq: Add linux/irq.h to make it compile again
m68k: amiga: Add linux/irq.h to make it compile again
irqchip: sun4i: Don't ack IRQs > 0, fix acking of IRQ 0
irqchip: sun4i: Fix a comment about mask register initialization
irqchip: sun4i: Fix irq 0 not working
genirq: Add a new IRQCHIP_EOI_THREADED flag
genirq: Document IRQCHIP_ONESHOT_SAFE flag
ARM: sunxi: dt: Convert to the new irq controller compatibles
irqchip: sunxi: Change compatibles
...
Pull s390 updates from Martin Schwidefsky:
"There are two memory management related changes, the CMMA support for
KVM to avoid swap-in of freed pages and the split page table lock for
the PMD level. These two come with common code changes in mm/.
A fix for the long standing theoretical TLB flush problem, this one
comes with a common code change in kernel/sched/.
Another set of changes is Heikos uaccess work, included is the initial
set of patches with more to come.
And fixes and cleanups as usual"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (36 commits)
s390/con3270: optionally disable auto update
s390/mm: remove unecessary parameter from pgste_ipte_notify
s390/mm: remove unnecessary parameter from gmap_do_ipte_notify
s390/mm: fixing comment so that parameter name match
s390/smp: limit number of cpus in possible cpu mask
hypfs: Add clarification for "weight_min" attribute
s390: update defconfigs
s390/ptrace: add support for PTRACE_SINGLEBLOCK
s390/perf: make print_debug_cf() static
s390/topology: Remove call to update_cpu_masks()
s390/compat: remove compat exec domain
s390: select CONFIG_TTY for use of tty in unconditional keyboard driver
s390/appldata_os: fix cpu array size calculation
s390/checksum: remove memset() within csum_partial_copy_from_user()
s390/uaccess: remove copy_from_user_real()
s390/sclp_early: Return correct HSA block count also for zero
s390: add some drivers/subsystems to the MAINTAINERS file
s390: improve debug feature usage
s390/airq: add support for irq ranges
s390/mm: enable split page table lock for PMD level
...
Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:
get_online_cpus();
for_each_online_cpu(cpu)
init_cpu(cpu);
register_cpu_notifier(&foobar_cpu_notifier);
put_online_cpus();
This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).
Instead, the correct and race-free way of performing the callback
registration is:
cpu_notifier_register_begin();
for_each_online_cpu(cpu)
init_cpu(cpu);
/* Note the use of the double underscored version of the API */
__register_cpu_notifier(&foobar_cpu_notifier);
cpu_notifier_register_done();
Fix the smp code in s390 by using this latter form of callback registration.
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:
get_online_cpus();
for_each_online_cpu(cpu)
init_cpu(cpu);
register_cpu_notifier(&foobar_cpu_notifier);
put_online_cpus();
This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).
Instead, the correct and race-free way of performing the callback
registration is:
cpu_notifier_register_begin();
for_each_online_cpu(cpu)
init_cpu(cpu);
/* Note the use of the double underscored version of the API */
__register_cpu_notifier(&foobar_cpu_notifier);
cpu_notifier_register_done();
Fix the cacheinfo code in s390 by using this latter form of callback
registration.
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Limit the number of bits to the maximum number of cpus a machine
can have.
possible_cpu_mask typically will have more bits set than a machine
may physically have. This results in wasted memory during per-cpu
memory allocations, if the possible mask contains more cpus than
physically possible for a given configuration.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The PTRACE_SINGLEBLOCK option is used to get control whenever
the inferior has executed a successful branch. The PER option to
implement block stepping is successful-branching event, bit 32
in the PER-event mask.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Merge the request/release callbacks which are in a separate branch for
consumption by the gpio folks.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
As the data parameter is not really used by any ftrace_dyn_arch_init,
remove that from ftrace_dyn_arch_init. This also removes the addr
local variable from ftrace_init which is now unused.
Note the documentation was imprecise as it did not suggest to set
(*data) to 0.
Link: http://lkml.kernel.org/r/1393268401-24379-4-git-send-email-jslaby@suse.cz
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
No architecture uses the "data" parameter in ftrace_dyn_arch_init() in any
way, it just sets the value to 0. And this is used as a return value
in the caller -- ftrace_init, which just checks the retval against
zero.
Note there is also "return 0" in every ftrace_dyn_arch_init. So it is
enough to check the retval and remove all the indirect sets of data on
all archs.
Link: http://lkml.kernel.org/r/1393268401-24379-3-git-send-email-jslaby@suse.cz
Cc: linux-arch@vger.kernel.org
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The call to update_cpu_masks() from within topology_init()
is completely redundant. This patch removes it.
Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The whole compat exec domain code doesn't make any difference.
From the registered s390_exec_domain:
- exec domain name is only displayed in /proc/execdomains
- handler is unused
- pers_low and pers_high are only used internally to find this specific
exec domain otherwise the default exec domain will be used
- all other fields match the default exec domain
So let's get rid of this.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Now that all compat syscalls have been converted to use the
COMPAT_SYSCALL_DEFINE macros, we don't need to compat syscall
wrapper assembly code anymore.
So remove it and fix up the system call table accordingly.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
commit: 8f945a33 (genirq: Move kstat_incr_irqs_this_cpu() to core)
unearthed the following:
arch/s390/kernel/irq.c: In function 'init_IRQ':
>> arch/s390/kernel/irq.c:93:2: error: implicit declaration of function 'irq_reserve_irqs'
[-Werror=implicit-function-declaration]
....
cc1: some warnings being treated as errors
--
drivers/s390/cio/cio.c: In function 'init_cio_interrupts':
>> drivers/s390/cio/cio.c:594:2: error: implicit declaration of function
'irq_set_chip_and_handler' [-Werror=implicit-function-declaration]
[-Werror=implicit-function-declaration]
....
cc1: some warnings being treated as errors
The reason is that those files require linux/irq.h and magically
pulled that in via linux/kernel_stat.h
The commit above got rid of the pointless include of linux/irq.h in
linux/kernel_stat.h and therefor broke the build.
Include linux/irq.h
Reported-by: fengguang.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: s390 <linux-s390@vger.kernel.org>
Implement the new CCW_CMD_SET_IND_ADAPTER command and try to enable
adapter interrupts for every device on the first startup. If the host
does not support adapter interrupts, fall back to normal I/O interrupts.
virtio-ccw adapter interrupts use the same isc as normal I/O subchannels
and share a summary indicator for all devices sharing the same indicator
area.
Indicator bits for the individual virtqueues may be contained in the same
indicator area for different devices.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Parameter conversion within the system call wrappers is only needed
for parameters which differ in size and have a size of eight bytes on
64 bit.
For system call parameters with a size of less than eight byte the
called system call itself will perform parameter conversion anyway.
So we can save the double conversion of e.g. int parameters.
The only types which need to be converted are therefore pointer and
(unsigned) long parameters.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Instead of explicitly changing compat system call parameters from e.g.
unsigned long to compat_ulong_t let the COMPAT_SYSCALL_WRAP macros
automatically detect (unsigned) long parameters and zero and sign
extend them automatically.
The resulting binary is completely identical.
In addition add a sys_[system call name] prototype for each system call
wrapper. This will cause compile errors if the prototype does not match
the prototype in include/linux/syscall.h.
Therefore we should now always get the correct zero and sign extension
of system call parameters. Pointers are handled like before.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
The compat syscall wrappers for sync_file_range and fallocate merged 32 bit
parameters into 64 bit parameters. Therefore they did more than just the
usual zero and/or sign extension of system call parameters.
So convert these two wrappers to full s390 specific compat sytem calls.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Introduce a new compat_wrap.c file which contains the s390 specific compat
system call wrappers.
The s390 specific system call wrappers only perform sign, zero and pointer
conversion of system call arguments before actually calling the non-compat
system call.
Therefore introduce COMPAT_SYSCALL_WRAPx macros which generate C code that
is nearly identical to the assembly code. This has the advantage that the
compile will generate correct code, and we avoid the frequent copy-paste
errors seen in the compat_wrapper.S file.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Convert s390 specific system calls to to the new COMPAT_SYSCALL_DEFINE macro.
This allows us to get rid of the assembly compat wrappers.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Git commit 050eef364a "[S390] fix tlb flushing vs. concurrent
/proc accesses" introduced the attach counter to avoid using the
mm_users value to decide between IPTE for every PTE and lazy TLB
flushing with IDTE. That fixed the problem with mm_users but it
introduced another subtle race, fortunately one that is very hard
to hit.
The background is the requirement of the architecture that a valid
PTE may not be changed while it can be used concurrently by another
cpu. The decision between IPTE and lazy TLB flushing needs to be
done while the PTE is still valid. Now if the virtual cpu is
temporarily stopped after the decision to use lazy TLB flushing but
before the invalid bit of the PTE has been set, another cpu can attach
the mm, find that flush_mm is set, do the IDTE, return to userspace,
and recreate a TLB that uses the PTE in question. When the first,
stopped cpu continues it will change the PTE while it is attached on
another cpu. The first cpu will do another IDTE shortly after the
modification of the PTE which makes the race window quite short.
To fix this race the CPU that wants to attach the address space of a
user space thread needs to wait for the end of the PTE modification.
The number of concurrent TLB flushers for an mm is tracked in the
upper 16 bits of the attach_count and finish_arch_post_lock_switch
is used to wait for the end of the flush operation if required.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove another leftover from the time when we supported running
user space in either home or primary address space.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
MACHINE_HAS_MVCOS is used exactly once when the machine is brought up.
There is no need to cache the flag in the machine_flags.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There are only two uaccess variants on s390 left: the version that is used
if the mvcos instruction is available, and the page table walk variant.
So there is no need for expensive indirect function calls.
By default the mvcos variant will be called. If the mvcos instruction is not
available it will call the page table walk variant.
For minimal performance impact the "if (mvcos_is_available)" is implemented
with a jump label, which will be a six byte nop on machines with mvcos.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull s390 bugfixes from Martin Schwidefsky:
"A collection a bug fixes. Most of them are minor but two of them are
more severe. The linkage stack bug can be used by user space to force
an oops, with panic_on_oops this is a denial-of-service. And the dump
memory detection issue can cause incomplete memory dumps"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/cio: improve cio_commit_config
s390: fix kernel crash due to linkage stack instructions
s390/dump: Fix dump memory detection
s390/appldata: restore missing init_virt_timer()
s390/qdio: correct program-controlled interruption checking
s390/qdio: for_each macro correctness
The kernel currently crashes with a low-address-protection exception
if a user space process executes an instruction that tries to use the
linkage stack. Set the base-ASTE origin and the subspace-ASTE origin
of the dispatchable-unit-control-table to point to a dummy ASTE.
Set up control register 15 to point to an empty linkage stack with no
room left.
A user space process with a linkage stack instruction will still crash
but with a different exception which is correctly translated to a
segmentation fault instead of a kernel oops.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Change parameter types of s390's compat ipc syscall from unsigned long
to compat_ulong_t to enforce zero extension of these parameters.
This is not really a bug, since s390_ipc compat syscall is only a
wrapper to the generic compat_sys_ipc() syscall, which performs correct
zero and sign extension.
This was introduced with commit 56e41d3c5a ("merge compat sys_ipc
instances").
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull s390 updates from Martin Schwidefsky:
"The bulk of the s390 updates for v3.14.
New features are the perf support for the CPU-Measurement Sample
Facility and the EP11 support for the crypto cards. And the normal
cleanups and bug-fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (44 commits)
s390/cpum_sf: fix printk format warnings
s390: Fix misspellings using 'codespell' tool
s390/qdio: bridgeport support - CHSC part
s390: delete new instances of __cpuinit usage
s390/compat: fix PSW32_USER_BITS definition
s390/zcrypt: add support for EP11 coprocessor cards
s390/mm: optimize randomize_et_dyn for !PF_RANDOMIZE
s390: use IS_ENABLED to check if a CONFIG is set to y or m
s390/cio: use device_lock to synchronize calls to the ccwgroup driver
s390/cio: use device_lock to synchronize calls to the ccw driver
s390/cio: fix unlocked access of online member
s390/cpum_sf: Add flag to process full SDBs only
s390/cpum_sf: Add raw data sampling to support the diagnostic-sampling function
s390/cpum_sf: Filter perf events based event->attr.exclude_* settings
s390/cpum_sf: Detect KVM guest samples
s390/cpum_sf: Add helper to read TOD from trailer entries
s390/cpum_sf: Atomically reset trailer entry fields of sample-data-blocks
s390/cpum_sf: Dynamically extend the sampling buffer if overflows occur
s390/pci: reenable per default
s390/pci/dma: fix accounting of allocated_pages
...
The patch "s390/perf: add support for the CPU-Measurement Sampling
Facility" added a new instance of the __cpuinit macro usage.
We removed this a couple versions ago; we now want to remove
the compat no-op stubs. Introducing new users is not what
we want to see at this point in time, as it will break once
the stubs are gone.
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Skip the call to brk_rnd() if the PF_RANDOMIZE flag is not set for
the process. This avoids the costly get_random_int() call. Modify
arch_randomize_brk() as well to make it look like randomize_et_dyn().
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since under z/VM we cannot have more than 64 cpus, make sure the
cpu_possible_mask does not contain more bits.
This avoids wasting memory for dynamic per-cpu allocations if
CONFIG_NR_CPUS is larger than 64.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This is shorter and should be used instead of the longer form
which checks for both possible config options.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add the PERF_CPUM_SF_FULL_BLOCKS flag to process only sample-data-blocks that
have the block-full-indicator bit set. Sample-data-blocks that are partially
filled are discarded. Use this flag if the sampling buffer is likely to be
shared among perf events that use different sampling modes. In such
environments, flushing sample-data-blocks that are not completely filled, might
cause invalid-data-formats.
Setting PERF_CPUM_SF_FULL_BLOCKS prevents potentially invalid sampling data to
be processed but, in contrast, also discards valid samples in partially filled
sample-data-blocks. Note that sample-data-blocks might not become full for
small sampling frequencies or for workload that is scheduled for tiny intervals.
To sample with the PERF_CPUM_SF_FULL_BLOCKS flag, set the perf->attr.config1
to 0x0004. For example:
perf record -e cpum_sf/config=0xB000,config1=0x0004/
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Also support the diagnostic-sampling function in addition to the basic-sampling
function. Diagnostic-sampling data entries contain hardware model specific
sampling data and additional programs are required to analyze the data.
To deliver diagnostic-sampling, as well, as basis-sampling data entries to user
space, introduce support for sampling "raw data". If this particular perf
sampling type (PERF_SAMPLE_RAW) is used, sampling data entries are copied
to user space. External programs can then analyze these data.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce the perf_exclude_event() function to filter perf samples
according to event->attr.exclude_* settings. During event initialization,
reset event exclude settings that are not supported.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The host-program-parameter (hpp) value of basic sample-data-entries designates
a SIE control block that is set by the LPP instruction in sie64a().
Non-zero values indicate guest samples, a value of zero indicates a host sample.
For perf samples, host and guest samples are distinguished using particular
PERF_MISC_* flags. The perf layer calls perf_misc_flags() to set the flags
based on the pt_regs content. For each sample-data-entry, the cpum_sf PMU
creates a pt_regs structure with the sample-data information. An additional
flag structure is added to easily distinguish between host and guest samples.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The trailer entry contains a timestamp of the time when the sample-data-block
became full. The timestamp specifies a TOD (time-of-day) value in either the
STCK or STCKE format.
Provide a helper function to return the TOD value depending on the setting of
time format indicator.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Ensure to reset the sample-data-block full indicator and the overflow counter
at the same time. This must be done atomically because the sampling hardware
is still active while full sample-data-block is processed.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Improve the sampling buffer allocation and add a function to reallocate and
increase the sampling buffer structure. The number of allocated buffer elements
(sample-data-blocks) are accounted. You can control the minimum and maximum
number these sample-data-blocks through the cpum_sfb_size kernel parameter.
The number hardware sample overflows (if any) are also accounted and stored
per perf event. During the PMU disable/enable calls, the accumulated overflow
counter is analyzed and, if necessary, the sampling buffer is dynamically
increased.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Register a service level handler to report information about available
CPU-Measurement facilities.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce reserve/release functions to share the sampling facility
between perf and oprofile.
Also improve error handling for the sampling facility support in perf.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The cpum_cf (counter facility) PMU does not support sampling events.
With cpum_sf (sampling facility), a PMU for sampling CPU cycles is
available.
Make cpum_sf the "default" PMU for PERF_COUNT_HW_CPU_CYCLES sampling
events but use the more precise cpum_cf PMU for non-sampling events.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce a perf PMU, "cpum_sf", to support the CPU-Measurement
Sampling Facility. You can control the sampling facility through
this perf PMU interfaces. Perf sampling events are created for
hardware samples.
For details about the CPU-Measurement Sampling Facility, see
"The Load-Program-Parameter and the CPU-Measurement Facilities" (SA23-2260).
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Provide PMU event attributes for supported counters and export their symbolic
names to the sysfs "events" directory.
See the /sys/devices/cpum_cf/events/ directory for a list of available counters.
Note that you might require counter set authorizations for the LPAR to use them.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The return code of the __put_user call to store the rt_sigreturn
system call to the user stack if not properly checked, the err
variable is only checked before to the __put_user. Use an if
statement instead.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the embedded struct cpu from struct pcpu and replace it with a
pointer instead. The struct cpu now gets allocated when a new cpu gets
detected.
The size of the pcpu_devices array (NR_CPUS * sizeof(struct pcpu)) gets
reduced by nearly 120KB.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
It is less expensive to update control registers 0 and 2 with two
individual stctg/lctlg instructions as with a single one that spans
control register 0, 1 and 2.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The user_enable_single_step() and user_disable_sindle_step() functions
are always called on the inferior, never for the currently active
process. Remove the unnecessary check for the current process and
the update_cr_regs() call from the enable/disable functions.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If the per cpu ec_mask bit of the receiving cpu is already set there is
no need to send an ipi, since a different cpu has already sent an ipi
and the receiving cpu has not yet executed the external call ipi handler.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With git commit 79c74ecbeb
"s390/time,vdso: convert to the new update_vsyscall interface"
the new update_vsyscall function already does the sum of xtime
and wall_to_monotonic. The old update_vsyscall function only
copied the wall_to_monotonic offset. The vdso code needs to be
modified to take this into consideration.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The code to use the ECTG instruction to calculate the cputime for the
current thread is currently used only for the per-thread CPU-clock
with the clockid -2 (PID=0, VIRT=1). Use the same code for the clockid
CLOCK_THREAD_CPUTIME_ID to speed up the more common clockid as well.
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The access-list entry is supposed to have the fetch-only bit set, however
a reserved bit got set instead.
Userspace isn't able to write to the page anyway since the accessed page
has the read-only bit set. So this saves us only for bad surprises in the
future if the reserved bit gets used.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Git commit 9e34f2686bb088b211b6cac8772e1f644c6180f8
"s390/mm,tlb: tlb flush on page table upgrade fixup" removed the
exception handler for the asce-type exception. This is incorrect
as the user-copy with MVCOS can cause asce-type exceptions in
the kernel if a user pointer is too large. Those need to be
handled with do_no_context to branch to the fixup in the
user-copy code.
The simplest fix for this problem is to call do_dat_exception for
asce-type excpetions, as there is no vma for the address the code
will handle the exception correctly.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Git commit 4f37a68cda
"s390: Use direct ktime path for s390 clockevent device" makes use
of the CLOCK_EVT_FEAT_KTIME clockevent option to avoid the delta
calculation with ktime_get() in clockevents_program_event and the
get_tod_clock() in s390_next_event. This is based on the assumption
that the difference between the internal ktime and the hardware
clock is reflected in the wall_to_monotonic delta. But this is not
true, the ntp corrections are applied via changes to the tk->mult
multiplier and this is not reflected in wall_to_monotonic.
In theory this could be solved by using the raw monotonic clock
but it is simpler to switch back to the standard clock delta
calculation.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Switch to the improved update_vsyscall interface that provides
sub-nanosecond precision for gettimeofday and clock_gettime.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Commit "s390: fix handling of runtime instrumentation psw bit" (5ebf250dab)
changed the behavior of setting the runtime instrumentation psw bit. This
commit restores the original logic:
1. When returning from the signal handler, the runtime instrumentation psw bit
is restored to its saved state.
2. If the runtime instrumentation psw bit is enabled during the signal handler,
it is always turned off when leaving the signal handler. The saved state
is restored as described in 1. That also implies that turning on runtime
instrumentation in the signal handler is only effective while running in the
signal context.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Pull second set of s390 patches from Martin Schwidefsky:
"The handling of the PCI hotplug notifications has been improved, the
zfcp dumper can now detect the HSA size dynamically and the default
install kernel has been changed to the compressed bzImage. And two
bug-fixes for scm and 3720"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/pci: implement hotplug notifications
s390/scm_block: do not hide eadm subchannel dependency
s390/sclp: Consolidate early sclp init calls to sclp_early_detect()
s390/sclp: Move early code from sclp_cmd.c to sclp_early.c
s390/sclp: Determine HSA size dynamically for zfcpdump
s390/sclp: Move declarations for sclp_sdias into separate header file
s390/pci: implement pcibios_remove_bus
s390/pci: improve handling of bus resources
s390/3270: fix missing device_destroy() call
s390/boot: Install bzImage as default kernel image
Pull trivial tree updates from Jiri Kosina:
"Usual earth-shaking, news-breaking, rocket science pile from
trivial.git"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
doc: usb: Fix typo in Documentation/usb/gadget_configs.txt
doc: add missing files to timers/00-INDEX
timekeeping: Fix some trivial typos in comments
mm: Fix some trivial typos in comments
irq: Fix some trivial typos in comments
NUMA: fix typos in Kconfig help text
mm: update 00-INDEX
doc: Documentation/DMA-attributes.txt fix typo
DRM: comment: `halve' -> `half'
Docs: Kconfig: `devlopers' -> `developers'
doc: typo on word accounting in kprobes.c in mutliple architectures
treewide: fix "usefull" typo
treewide: fix "distingush" typo
mm/Kconfig: Grammar s/an/a/
kexec: Typo s/the/then/
Documentation/kvm: Update cpuid documentation for steal time and pv eoi
treewide: Fix common typo in "identify"
__page_to_pfn: Fix typo in comment
Correct some typos for word frequency
clk: fixed-factor: Fix a trivial typo
...
The new function calls the old ones. The sclp_event_mask_early() is removed
and replaced by one invocation of sclp_set_event_mask(0, 0).
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently we have hardcoded the HSA size to 32 MiB. With this patch the
HSA size is determined dynamically via SCLP in early.c.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Merge first patch-bomb from Andrew Morton:
"Quite a lot of other stuff is banked up awaiting further
next->mainline merging, but this batch contains:
- Lots of random misc patches
- OCFS2
- Most of MM
- backlight updates
- lib/ updates
- printk updates
- checkpatch updates
- epoll tweaking
- rtc updates
- hfs
- hfsplus
- documentation
- procfs
- update gcov to gcc-4.7 format
- IPC"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (269 commits)
ipc, msg: fix message length check for negative values
ipc/util.c: remove unnecessary work pending test
devpts: plug the memory leak in kill_sb
./Makefile: export initial ramdisk compression config option
init/Kconfig: add option to disable kernel compression
drivers: w1: make w1_slave::flags long to avoid memory corruption
drivers/w1/masters/ds1wm.cuse dev_get_platdata()
drivers/memstick/core/ms_block.c: fix unreachable state in h_msb_read_page()
drivers/memstick/core/mspro_block.c: fix attributes array allocation
drivers/pps/clients/pps-gpio.c: remove redundant of_match_ptr
kernel/panic.c: reduce 1 byte usage for print tainted buffer
gcov: reuse kbasename helper
kernel/gcov/fs.c: use pr_warn()
kernel/module.c: use pr_foo()
gcov: compile specific gcov implementation based on gcc version
gcov: add support for gcc 4.7 gcov format
gcov: move gcov structs definitions to a gcc version specific file
kernel/taskstats.c: return -ENOMEM when alloc memory fails in add_del_listener()
kernel/taskstats.c: add nla_nest_cancel() for failure processing between nla_nest_start() and nla_nest_end()
kernel/sysctl_binary.c: use scnprintf() instead of snprintf()
...
Pull vfs updates from Al Viro:
"All kinds of stuff this time around; some more notable parts:
- RCU'd vfsmounts handling
- new primitives for coredump handling
- files_lock is gone
- Bruce's delegations handling series
- exportfs fixes
plus misc stuff all over the place"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (101 commits)
ecryptfs: ->f_op is never NULL
locks: break delegations on any attribute modification
locks: break delegations on link
locks: break delegations on rename
locks: helper functions for delegation breaking
locks: break delegations on unlink
namei: minor vfs_unlink cleanup
locks: implement delegations
locks: introduce new FL_DELEG lock flag
vfs: take i_mutex on renamed file
vfs: rename I_MUTEX_QUOTA now that it's not used for quotas
vfs: don't use PARENT/CHILD lock classes for non-directories
vfs: pull ext4's double-i_mutex-locking into common code
exportfs: fix quadratic behavior in filehandle lookup
exportfs: better variable name
exportfs: move most of reconnect_path to helper function
exportfs: eliminate unused "noprogress" counter
exportfs: stop retrying once we race with rename/remove
exportfs: clear DISCONNECTED on all parents sooner
exportfs: more detailed comment for path_reconnect
...
Use more appropriate NUMA_NO_NODE instead of -1 in all archs' module_alloc()
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull IRQ changes from Ingo Molnar:
"The biggest change this cycle are the softirq/hardirq stack
interaction and nesting fixes, cleanups and reorganizations from
Frederic. This is the longer followup story to the softirq nesting
fix that is already upstream (commit ded7975475: "irq: Force hardirq
exit's softirq processing on its own stack")"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip: bcm2835: Convert to use IRQCHIP_DECLARE macro
powerpc: Tell about irq stack coverage
x86: Tell about irq stack coverage
irq: Optimize softirq stack selection in irq exit
irq: Justify the various softirq stack choices
irq: Improve a bit softirq debugging
irq: Optimize call to softirq on hardirq exit
irq: Consolidate do_softirq() arch overriden implementations
x86/irq: Correct comment about i8259 initialization
The IDTE instruction used to flush TLB entries for a specific address
space uses the address-space-control element (ASCE) to identify
affected TLB entries. The upgrade of a page table adds a new top
level page table which changes the ASCE. The TLB entries associated
with the old ASCE need to be flushed and the ASCE for the address space
needs to be replaced synchronously on all CPUs which currently use it.
The concept of a lazy ASCE update with an exception handler is broken.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use the ACCESS_ONCE macro for both accesses to idle->sequence in the
loops to calculate the idle time. If only one access uses the macro,
the compiler is free to cache the value for the second access which
can cause endless loops.
Cc: stable@vger.kernel.org # 3.6+
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This typedef is unnecessary and should just be removed.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Make psw32_user_bits a constant value again.
This is a leftover of the code which allowed to run the kernel either
in primary or home space which got removed with 9a905662 "s390/uaccess:
always run the kernel in home space".
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix the following bugs:
- When returning from a signal the signal handler copies the saved psw mask
from user space and uses parts of it. Especially it restores the RI bit
unconditionally. If however the machine doesn't support RI, or RI is
disabled for the task, the last lpswe instruction which returns to user
space will generate a specification exception.
To fix this check if the RI bit is allowed to be set and kill the task
if not.
- In the compat mode signal handler code the RI bit of the psw mask gets
propagated to the mask of the return psw: if user space enables RI in the
signal handler, RI will also be enabled after the signal handler is
finished.
This is a different behaviour than with 64 bit tasks. So change this to
match the 64 bit semantics, which restores the original RI bit value.
- Fix similar oddities within the ptrace code as well.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The FPC_VALID_MASK has been used to check the validity of the value
to be loaded into the floating-point-control register. With the
introduction of the floating-point extension facility and the
decimal-floating-point additional bits have been defined which need
to be checked in a non straight forward way. So far these bits have
been ignored which can cause an incorrect results for decimal-
floating-point operations, e.g. an incorrect rounding mode to be
set after signal return.
The static check with the FPC_VALID_MASK is replaced with a trial
load of the floating-point-control value, see test_fp_ctl.
In addition an information leak with the padding word between the
floating-point-control word and the floating-point registers in
the s390_fp_regs is fixed.
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Get rid of this one:
arch/s390/kernel/cache.c: In function 'cache_build_info':
arch/s390/kernel/cache.c:144: warning: 'private' may be used uninitialized
in this function
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Instead of returnin the number of bytes not copied and/or -EFAULT let the
signal handler helper functions always return -EFAULT if a user space
access failed.
This doesn't fix a bug in the current code, but makes is harder to get it
wrong in the future.
Also "smatch" won't complain anymore about the fact that the number of
remaining bytes gets returned instead of -EFAULT.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently zfpcdump can only collect registers for up to CONFIG_NR_CPUS
CPUss. This dependency is not necessary. So remove it by dynamically
allocating the save area array.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Steven Rostedt noted that s390 is the only architecture which calls
ftrace_push_return_trace() before ftrace_graph_entry() and therefore has
the small advantage that trace.depth gets initialized automatically.
However this small advantage isn't worth the difference and possible subtle
breakage that may result from this.
So change s390 to have the same function call order like all other
architectures: first ftrace_graph_entry(), then ftrace_push_return_trace()
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Get rid of this compile warning:
arch/s390/kernel/crash_dump.c: In function 'copy_from_realmem':
arch/s390/kernel/crash_dump.c:48:6: warning: unused variable 'rc'
[-Wunused-variable]
int rc;
^
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With dirty and referenced bits implemented in software it is unnecessary
to initialize the storage key for every page. With this patch not a single
storage key operation is done for a system that does not use KVM.
For KVM set_pte_at/pgste_set_key will do the initialization for the guest
view of the storage key when the mapping for the page is established in
the host.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Simplify the uaccess code by removing the user_mode=home option.
The kernel will now always run in the home space mode.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Just like all other architectures we should use out-of-line find bit
operations, since the inline variant bloat the size of the kernel image.
And also like all other architecures we should only supply optimized
variants of the __ffs, ffs, etc. primitives.
Therefore this patch removes the inlined s390 find bit functions and uses
the generic out-of-line variants instead.
The optimization of the primitives follows with the next patch.
With this patch also the functions find_first_bit_left() and
find_next_bit_left() have been reimplemented, since logically, they are
nothing else but a find_first_bit()/find_next_bit() implementation that
use an inverted __fls() instead of __ffs().
Also the restriction that these functions only work on machines which
support the "flogr" instruction is gone now.
This reduces the size of the kernel image (defconfig, -march=z9-109)
by 144,482 bytes.
Alone the size of the function build_sched_domains() gets reduced from
7 KB to 3,5 KB.
We also git rid of unused functions like find_first_bit_le()...
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since zEC12 we have the interlocked-access facility 2 which allows to
use the instructions ni/oi/xi to update a single byte in storage with
compare-and-swap semantics.
So change set_bit(), clear_bit() and change_bit() to generate such code
instead of a compare-and-swap loop (or using the load-and-* instruction
family), if possible.
This reduces the text segment by yet another 8KB (defconfig).
Alternatively the long displacement variants niy/oiy/xiy could have
been used, but the extended displacement field is usually not needed
and therefore would only increase the size of the text segment again.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove CONFIG_SMP from bitops code. This reduces the C code significantly
but also generates better code for the SMP case.
This means that for !CONFIG_SMP set_bit() and friends now also have
compare and swap semantics (read: more code). However nobody really cares
for !CONFIG_SMP and this is the trade-off to simplify the SMP code which we
do care about.
The non-atomic bitops like __set_bit() now generate also better code
because the old code did not have a __builtin_contant_p() check for the
CONFIG_SMP case and therefore always generated the inline assembly variant.
However the inline assemblies for the non-atomic case now got completely
removed since gcc can produce better code, which accesses less memory
operands.
test_bit() got also a bit simplified since it did have a
__builtin_constant_p() check, however two identical code pathes for each
case (written differently).
In result this mainly reduces the to be maintained code but is not very
relevant for code generation, since there are not many non-atomic bitops
usages that we care about.
(code reduction defconfig kernel image before/after: 560 bytes).
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since we have an in-kernel disassembler we can make sure that
there won't be any kprobes set on random data.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
