smpboot is very creative with the ways to disable ioapic.
smpboot_clear_io_apic() smpboot_clear_io_apic_irqs() and
disable_ioapic_support() serve a similar purpose.
smpboot_clear_io_apic_irqs() is the most useless of all
functions as it clears a variable which has not been setup yet.
Aside of that it has the same ifdef mess and conditionals around the
ioapic related code, which can now be removed.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211703.650280684@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arch/x86/kvm/emulate.c: In function ‘check_cr_write’:
arch/x86/kvm/emulate.c:3552:4: warning: left shift count >= width of type
rsvd = CR3_L_MODE_RESERVED_BITS & ~CR3_PCID_INVD;
happens because sizeof(UL) on 32-bit is 4 bytes but we shift it 63 bits
to the left.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull RCU updates from Paul E. McKenney:
- Documentation updates.
- Miscellaneous fixes.
- Preemptible-RCU fixes, including fixing an old bug in the
interaction of RCU priority boosting and CPU hotplug.
- SRCU updates.
- RCU CPU stall-warning updates.
- RCU torture-test updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
SuSE's 2.6.16 kernel fails to boot if the delta between tsc_timestamp
and rdtsc is larger than a given threshold:
* If we get more than the below threshold into the future, we rerequest
* the real time from the host again which has only little offset then
* that we need to adjust using the TSC.
*
* For now that threshold is 1/5th of a jiffie. That should be good
* enough accuracy for completely broken systems, but also give us swing
* to not call out to the host all the time.
*/
#define PVCLOCK_DELTA_MAX ((1000000000ULL / HZ) / 5)
Disable masterclock support (which increases said delta) in case the
boot vcpu does not use MSR_KVM_SYSTEM_TIME_NEW.
Upstreams kernels which support pvclock vsyscalls (and therefore make
use of PVCLOCK_STABLE_BIT) use MSR_KVM_SYSTEM_TIME_NEW.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
arch/x86/kvm/x86.c:495:5: sparse: symbol 'kvm_read_nested_guest_page' was not declared. Should it be static?
arch/x86/kvm/x86.c:646:5: sparse: symbol '__kvm_set_xcr' was not declared. Should it be static?
arch/x86/kvm/x86.c:1183:15: sparse: symbol 'max_tsc_khz' was not declared. Should it be static?
arch/x86/kvm/x86.c:1237:6: sparse: symbol 'kvm_track_tsc_matching' was not declared. Should it be static?
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In Dom0's the use of the TSC clocksource (whenever it is stable enough to
be used) instead of the Xen clocksource should not cause any issues, as
Dom0 VMs never live-migrated. The TSC clocksource is somewhat more
efficient than the Xen paravirtualised clocksource, thus it should have
higher rating.
This patch decreases the rating of the Xen clocksource in Dom0s to 275.
Which is half-way between the rating of the TSC clocksource (300) and the
hpet clocksource (250).
Cc: Anthony Liguori <aliguori@amazon.com>
Signed-off-by: Imre Palik <imrep@amazon.de>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Change ARCH_HAVE_LIVE_PATCHING to HAVE_LIVE_PATCHING in Kconfigs. HAVE_
bools are prevalent there and we should go with the flow.
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
math_state_restore() can race with kernel_fpu_begin() if irq comes
right after __thread_fpu_begin(), __save_init_fpu() will overwrite
fpu->state we are going to restore.
Add 2 simple helpers, kernel_fpu_disable() and kernel_fpu_enable()
which simply set/clear in_kernel_fpu, and change math_state_restore()
to exclude kernel_fpu_begin() in between.
Alternatively we could use local_irq_save/restore, but probably these
new helpers can have more users.
Perhaps they should disable/enable preemption themselves, in this case
we can remove preempt_disable() in __restore_xstate_sig().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: matt.fleming@intel.com
Cc: bp@suse.de
Cc: pbonzini@redhat.com
Cc: luto@amacapital.net
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Link: http://lkml.kernel.org/r/20150115192028.GD27332@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Now that we have in_kernel_fpu we can remove __thread_clear_has_fpu()
in __kernel_fpu_begin(). And this allows to replace the asymmetrical
and nontrivial use_eager_fpu + tsk_used_math check in kernel_fpu_end()
with the same __thread_has_fpu() check.
The logic becomes really simple; if _begin() does save() then _end()
needs restore(), this is controlled by __thread_has_fpu(). Otherwise
they do clts/stts unless use_eager_fpu().
Not only this makes begin/end symmetrical and imo more understandable,
potentially this allows to change irq_fpu_usable() to avoid all other
checks except "in_kernel_fpu".
Also, with this patch __kernel_fpu_end() does restore_fpu_checking()
and WARNs if it fails instead of math_state_restore(). I think this
looks better because we no longer need __thread_fpu_begin(), and it
would be better to report the failure in this case.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: matt.fleming@intel.com
Cc: bp@suse.de
Cc: pbonzini@redhat.com
Cc: luto@amacapital.net
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Link: http://lkml.kernel.org/r/20150115192005.GC27332@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
interrupted_kernel_fpu_idle() tries to detect if kernel_fpu_begin()
is safe or not. In particular it should obviously deny the nested
kernel_fpu_begin() and this logic looks very confusing.
If use_eager_fpu() == T we rely on a) __thread_has_fpu() check in
interrupted_kernel_fpu_idle(), and b) on the fact that _begin() does
__thread_clear_has_fpu().
Otherwise we demand that the interrupted task has no FPU if it is in
kernel mode, this works because __kernel_fpu_begin() does clts() and
interrupted_kernel_fpu_idle() checks X86_CR0_TS.
Add the per-cpu "bool in_kernel_fpu" variable, and change this code
to check/set/clear it. This allows to do more cleanups and fixes, see
the next changes.
The patch also moves WARN_ON_ONCE() under preempt_disable() just to
make this_cpu_read() look better, this is not really needed. And in
fact I think we should move it into __kernel_fpu_begin().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: matt.fleming@intel.com
Cc: bp@suse.de
Cc: pbonzini@redhat.com
Cc: luto@amacapital.net
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Link: http://lkml.kernel.org/r/20150115191943.GB27332@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Currently Xen Domain0 has special treatment for ACPI SCI interrupt,
that is initialize irq for ACPI SCI at early stage in a special way as:
xen_init_IRQ()
->pci_xen_initial_domain()
->xen_setup_acpi_sci()
Allocate and initialize irq for ACPI SCI
Function xen_setup_acpi_sci() calls acpi_gsi_to_irq() to get an irq
number for ACPI SCI. But unfortunately acpi_gsi_to_irq() depends on
IOAPIC irqdomains through following path
acpi_gsi_to_irq()
->mp_map_gsi_to_irq()
->mp_map_pin_to_irq()
->check IOAPIC irqdomain
For PV domains, it uses Xen event based interrupt manangement and
doesn't make uses of native IOAPIC, so no irqdomains created for IOAPIC.
This causes Xen domain0 fail to install interrupt handler for ACPI SCI
and all ACPI events will be lost. Please refer to:
https://lkml.org/lkml/2014/12/19/178
So the fix is to get rid of special treatment for ACPI SCI, just treat
ACPI SCI as normal GSI interrupt as:
acpi_gsi_to_irq()
->acpi_register_gsi()
->acpi_register_gsi_xen()
->xen_register_gsi()
With above change, there's no need for xen_setup_acpi_sci() anymore.
The above change also works with bare metal kernel too.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Cc: Tony Luck <tony.luck@intel.com>
Cc: xen-devel@lists.xenproject.org
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/1421720467-7709-2-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pull crypto fix from Herbert Xu:
"This fixes a regression that arose from the change to add a crypto
prefix to module names which was done to prevent the loading of
arbitrary modules through the Crypto API.
In particular, a number of modules were missing the crypto prefix
which meant that they could no longer be autoloaded"
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: add missing crypto module aliases
commit 78bff1c868 ("x86/ticketlock: Fix spin_unlock_wait() livelock")
introduced two additional ACCESS_ONCE cases in x86 spinlock.h.
Lets change those as well.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
ACCESS_ONCE does not work reliably on non-scalar types. For
example gcc 4.6 and 4.7 might remove the volatile tag for such
accesses during the SRA (scalar replacement of aggregates) step
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)
Change the p2m code to replace ACCESS_ONCE with READ_ONCE.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>
Removes some functions that are not used anywhere:
cpu_has_vmx_eptp_writeback() cpu_has_vmx_eptp_uncacheable()
This was partially found by using a static code analysis program called cppcheck.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, but also two PMU driver fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf tools powerpc: Use dwfl_report_elf() instead of offline.
perf tools: Fix segfault for symbol annotation on TUI
perf test: Fix dwarf unwind using libunwind.
perf tools: Avoid build splat for syscall numbers with uclibc
perf tools: Elide strlcpy warning with uclibc
perf tools: Fix statfs.f_type data type mismatch build error with uclibc
tools: Remove bitops/hweight usage of bits in tools/perf
perf machine: Fix __machine__findnew_thread() error path
perf tools: Fix building error in x86_64 when dwarf unwind is on
perf probe: Propagate error code when write(2) failed
perf/x86/intel: Fix bug for "cycles:p" and "cycles:pp" on SLM
perf/rapl: Fix sysfs_show() initialization for RAPL PMU
The int_ret_from_sys_call and syscall tracing code disagrees
with the sysret path as to the value of RCX.
The Intel SDM, the AMD APM, and my laptop all agree that sysret
returns with RCX == RIP. The syscall tracing code does not
respect this property.
For example, this program:
int main()
{
extern const char syscall_rip[];
unsigned long rcx = 1;
unsigned long orig_rcx = rcx;
asm ("mov $-1, %%eax\n\t"
"syscall\n\t"
"syscall_rip:"
: "+c" (rcx) : : "r11");
printf("syscall: RCX = %lX RIP = %lX orig RCX = %lx\n",
rcx, (unsigned long)syscall_rip, orig_rcx);
return 0;
}
prints:
syscall: RCX = 400556 RIP = 400556 orig RCX = 1
Running it under strace gives this instead:
syscall: RCX = FFFFFFFFFFFFFFFF RIP = 400556 orig RCX = 1
This changes FIXUP_TOP_OF_STACK to match sysret, causing the
test to show RCX == RIP even under strace.
It looks like this is a partial revert of:
88e4bc32686e ("[PATCH] x86-64 architecture specific sync for 2.5.8")
from the historic git tree.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/c9a418c3dc3993cb88bb7773800225fd318a4c67.1421453410.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull ftrace fixes from Steven Rostedt:
"This holds a few fixes to the ftrace infrastructure as well as the
mixture of function graph tracing and kprobes.
When jprobes and function graph tracing is enabled at the same time it
will crash the system:
# modprobe jprobe_example
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
After the first fork (jprobe_example probes it), the system will
crash.
This is due to the way jprobes copies the stack frame and does not do
a normal function return. This messes up with the function graph
tracing accounting which hijacks the return address from the stack and
replaces it with a hook function. It saves the return addresses in a
separate stack to put back the correct return address when done. But
because the jprobe functions do not do a normal return, their stack
addresses are not put back until the function they probe is called,
which means that the probed function will get the return address of
the jprobe handler instead of its own.
The simple fix here was to disable function graph tracing while the
jprobe handler is being called.
While debugging this I found two minor bugs with the function graph
tracing.
The first was about the function graph tracer sharing its function
hash with the function tracer (they both get filtered by the same
input). The changing of the set_ftrace_filter would not sync the
function recording records after a change if the function tracer was
disabled but the function graph tracer was enabled. This was due to
the update only checking one of the ops instead of the shared ops to
see if they were enabled and should perform the sync. This caused the
ftrace accounting to break and a ftrace_bug() would be triggered,
disabling ftrace until a reboot.
The second was that the check to update records only checked one of
the filter hashes. It needs to test both the "filter" and "notrace"
hashes. The "filter" hash determines what functions to trace where as
the "notrace" hash determines what functions not to trace (trace all
but these). Both hashes need to be passed to the update code to find
out what change is being done during the update. This also broke the
ftrace record accounting and triggered a ftrace_bug().
This patch set also include two more fixes that were reported
separately from the kprobe issue.
One was that init_ftrace_syscalls() was called twice at boot up. This
is not a major bug, but that call performed a rather large kmalloc
(NR_syscalls * sizeof(*syscalls_metadata)). The second call made the
first one a memory leak, and wastes memory.
The other fix is a regression caused by an update in the v3.19 merge
window. The moving to enable events early, moved the enabling before
PID 1 was created. The syscall events require setting the
TIF_SYSCALL_TRACEPOINT for all tasks. But for_each_process_thread()
does not include the swapper task (PID 0), and ended up being a nop.
A suggested fix was to add the init_task() to have its flag set, but I
didn't really want to mess with PID 0 for this minor bug. Instead I
disable and re-enable events again at early_initcall() where it use to
be enabled. This also handles any other event that might have its own
reg function that could break at early boot up"
* tag 'trace-fixes-v3.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix enabling of syscall events on the command line
tracing: Remove extra call to init_ftrace_syscalls()
ftrace/jprobes/x86: Fix conflict between jprobes and function graph tracing
ftrace: Check both notrace and filter for old hash
ftrace: Fix updating of filters for shared global_ops filters
We now have a generic function that does most of the work of
kvm_vm_ioctl_get_dirty_log, now use it.
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
cycles:p and cycles:pp do not work on SLM since commit:
86a04461a9 ("perf/x86: Revamp PEBS event selection")
UOPS_RETIRED.ALL is not a PEBS capable event, so it should not be used
to count cycle number.
Actually SLM calls intel_pebs_aliases_core2() which uses INST_RETIRED.ANY_P
to count the number of cycles. It's a PEBS capable event. But inv and
cmask must be set to count cycles.
Considering SLM allows all events as PEBS with no flags, only
INST_RETIRED.ANY_P, inv=1, cmask=16 needs to handled specially.
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421084541-31639-1-git-send-email-kan.liang@intel.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>