During early boot TSC and CPU frequency can be calibrated using MSR, CPUID,
and quick PIT calibration methods. The other methods PIT/HPET/PMTIMER are
available only after ACPI is initialized.

Split native_calibrate_cpu() into early and late parts so they can be
called separately during early and late tsc calibration.
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-26-pasha.tatashin@oracle.com

sched_clock_running may be read every time sched_clock_cpu() is called.
Yet, this variable is updated only twice during boot, and never changes
again, therefore it is better to make it a static key.
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-25-pasha.tatashin@oracle.com

Allow sched_clock() to be used before schec_clock_init() is called.  This
provides a way to get early boot timestamps on machines with unstable
clocks.
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-24-pasha.tatashin@oracle.com

sched_clock_postinit() initializes a generic clock on systems where no
other clock is provided. This function may be called only after
timekeeping_init().

Rename sched_clock_postinit to generic_clock_inti() and call it from
sched_clock_init(). Move the call for sched_clock_init() until after
time_init().
Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-23-pasha.tatashin@oracle.com

All prerequesites for enabling TSC as sched clock early in the boot
process are available now:

 - Early attempt of TSC calibration

 - Early availablity of static branch patching

If TSC frequency can be established in the early calibration, enable the
static key which switches sched clock to use TSC.

[ tglx: Massaged changelog ]
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-22-pasha.tatashin@oracle.com

cyc2ns converts tsc to nanoseconds, and it is handled in a per-cpu data
structure.

Currently, the setup code for c2ns data for every possible CPU goes through
the same sequence of calculations as for the boot CPU, but is based on the
same tsc frequency as the boot CPU, and thus this is not necessary.

Initialize the boot cpu when tsc frequency is determined. Copy the
calculated data from the boot CPU to the other CPUs in tsc_init().

In addition do the following:

 - Remove unnecessary zeroing of c2ns data by removing cyc2ns_data_init()

 - Split set_cyc2ns_scale() into two functions, so set_cyc2ns_scale() can be
   called when system is up, and wraps around __set_cyc2ns_scale() that can
   be called directly when system is booting but avoids saving restoring
   IRQs and going and waking up from idle.
Suggested-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-21-pasha.tatashin@oracle.com

During boot tsc is calibrated twice: once in tsc_early_delay_calibrate(),
and the second time in tsc_init().

Rename tsc_early_delay_calibrate() to tsc_early_init(), and rework it so
the calibration is done only early, and make tsc_init() to use the values
already determined in tsc_early_init().

Sometimes it is not possible to determine tsc early, as the subsystem that
is required is not yet initialized, in such case try again later in
tsc_init().
Suggested-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-20-pasha.tatashin@oracle.com

read_boot_clock64() is deleted, and replaced with
read_persistent_wall_and_boot_offset().

The default implementation of read_persistent_wall_and_boot_offset()
provides a better fallback than the current stubs for read_boot_clock64()
that arm has with no users, so remove the old code.
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-19-pasha.tatashin@oracle.com

read_boot_clock64() was replaced by read_persistent_wall_and_boot_offset()
so remove it.
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-18-pasha.tatashin@oracle.com

read_persistent_wall_and_boot_offset() is called during boot to read
both the persistent clock and also return the offset between the boot time
and the value of persistent clock.

Change the default boot_offset from zero to local_clock() so architectures,
that do not have a dedicated boot_clock but have early sched_clock(), such
as SPARCv9, x86, and possibly more will benefit from this change by getting
a better and more consistent estimate of the boot time without need for an
arch specific implementation.
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-17-pasha.tatashin@oracle.com

If architecture does not support exact boot time, it is challenging to
estimate boot time without having a reference to the current persistent
clock value. Yet, it cannot read the persistent clock time again, because
this may lead to math discrepancies with the caller of read_boot_clock64()
who have read the persistent clock at a different time.

This is why it is better to provide two values simultaneously: the
persistent clock value, and the boot time.

Replace read_boot_clock64() with:
read_persistent_wall_and_boot_offset(wall_time, boot_offset)

Where wall_time is returned by read_persistent_clock() And boot_offset is
wall_time - boot time, which defaults to 0.
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-16-pasha.tatashin@oracle.com

read_persistent_wall_and_boot_offset() will replace read_boot_clock64()
because on some architectures it is more convenient to read both sources
as one may depend on the other. For s390, implementation is the same
as read_boot_clock64() but also calling and returning value of
read_persistent_clock64()
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-15-pasha.tatashin@oracle.com

It is expected for sched_clock() to output data from 0, when system boots.

Add an offset xen_sched_clock_offset (similarly how it is done in other
hypervisors i.e. kvm_sched_clock_offset) to count sched_clock() from 0,
when time is first initialized.
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-14-pasha.tatashin@oracle.com

In every hypervisor except for xen pv time ops are initialized in
init_hypervisor_platform().

Xen PV domains initialize time ops in x86_init.paging.pagetable_init(),
by calling xen_setup_shared_info() which is a poor design, as time is
needed prior to memory allocator.

xen_setup_shared_info() is called from two places: during boot, and
after suspend. Split the content of xen_setup_shared_info() into
three places:

1. add the clock relavent data into new xen pv init_platform vector, and
   set clock ops in there.

2. move xen_setup_vcpu_info_placement() to new xen_pv_guest_late_init()
   call.

3. Re-initializing parts of shared info copy to xen_pv_post_suspend() to
   be symmetric to xen_pv_pre_suspend
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-13-pasha.tatashin@oracle.com

Currently, the notsc kernel parameter disables the use of the TSC by
sched_clock(). However, this parameter does not prevent the kernel from
accessing tsc in other places.

The only rationale to boot with notsc is to avoid timing discrepancies on
multi-socket systems where TSC are not properly synchronized, and thus
exclude TSC from being used for time keeping. But that prevents using TSC
as sched_clock() as well, which is not necessary as the core sched_clock()
implementation can handle non synchronized TSC based sched clocks just
fine.

However, there is another method to solve the above problem: booting with
tsc=unstable parameter. This parameter allows sched_clock() to use TSC and
just excludes it from timekeeping.

So there is no real reason to keep notsc, but for compatibility reasons the
parameter has to stay. Make it behave like 'tsc=unstable' instead.

[ tglx: Massaged changelog ]
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NDou Liyang <douly.fnst@cn.fujitsu.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-12-pasha.tatashin@oracle.com

Make it use the setup_* variants and have it be called only on the BSP and
drop the call in generic_identify() - X86_FEATURE_NOPL will be replicated
to the APs through the forced caps. Helps to keep the mess at a manageable
level.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-11-pasha.tatashin@oracle.com

Static branching is useful to runtime patch branches that are used in hot
path, but are infrequently changed.

The x86 clock framework is one example that uses static branches to setup
the best clock during boot and never changes it again.

It is desired to enable the TSC based sched clock early to allow fine
grained boot time analysis early on. That requires the static branching
functionality to be functional early as well.

Static branching requires patching nop instructions, thus,
arch_init_ideal_nops() must be called prior to jump_label_init().

Do all the necessary steps to call arch_init_ideal_nops() right after
early_cpu_init(), which also allows to insert a call to jump_label_init()
right after that. jump_label_init() will be called again from the generic
init code, but the code is protected against reinitialization already.

[ tglx: Massaged changelog ]
Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-10-pasha.tatashin@oracle.com

It supposed to be safe to modify static branches after jump_label_init().
But, because static key modifying code eventually calls text_poke() it can
end up accessing a struct page which has not been initialized yet.

Here is how to quickly reproduce the problem. Insert code like this
into init/main.c:

| +static DEFINE_STATIC_KEY_FALSE(__test);
| asmlinkage __visible void __init start_kernel(void)
| {
|        char *command_line;
|@@ -587,6 +609,10 @@ asmlinkage __visible void __init start_kernel(void)
|        vfs_caches_init_early();
|        sort_main_extable();
|        trap_init();
|+       {
|+       static_branch_enable(&__test);
|+       WARN_ON(!static_branch_likely(&__test));
|+       }
|        mm_init();

The following warnings show-up:
WARNING: CPU: 0 PID: 0 at arch/x86/kernel/alternative.c:701 text_poke+0x20d/0x230
RIP: 0010:text_poke+0x20d/0x230
Call Trace:
 ? text_poke_bp+0x50/0xda
 ? arch_jump_label_transform+0x89/0xe0
 ? __jump_label_update+0x78/0xb0
 ? static_key_enable_cpuslocked+0x4d/0x80
 ? static_key_enable+0x11/0x20
 ? start_kernel+0x23e/0x4c8
 ? secondary_startup_64+0xa5/0xb0

---[ end trace abdc99c031b8a90a ]---

If the code above is moved after mm_init(), no warning is shown, as struct
pages are initialized during handover from memblock.

Use text_poke_early() in static branching until early boot IRQs are enabled
and from there switch to text_poke. Also, ensure text_poke() is never
invoked when unitialized memory access may happen by using adding a
!after_bootmem assertion.
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-9-pasha.tatashin@oracle.com

The previous removal of the memblock dependency from kvmclock introduced a
static data array sized 64bytes * CONFIG_NR_CPUS. That's wasteful on large
systems when kvmclock is not used.

Replace it with:

 - A static page sized array of pvclock data. It's page sized because the
   pvclock data of the boot cpu is mapped into the VDSO so otherwise random
   other data would be exposed to the vDSO

 - A PER_CPU variable of pvclock data pointers. This is used to access the
   pcvlock data storage on each CPU.

The setup is done in two stages:

 - Early boot stores the pointer to the static page for the boot CPU in
   the per cpu data.

 - In the preparatory stage of CPU hotplug assign either an element of
   the static array (when the CPU number is in that range) or allocate
   memory and initialize the per cpu pointer.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Link: https://lkml.kernel.org/r/20180719205545.16512-8-pasha.tatashin@oracle.com

There is no point to have this in the kvm code itself and call it from
there. This can be called from an initcall and the parameter is cleared
when the hypervisor is not KVM.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Link: https://lkml.kernel.org/r/20180719205545.16512-7-pasha.tatashin@oracle.com

The kvmclock parameter is init data and the other variables are not
modified after init.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Link: https://lkml.kernel.org/r/20180719205545.16512-6-pasha.tatashin@oracle.com

- Cleanup the mrs write for wall clock. The type casts to (int) are sloppy
  because the wrmsr parameters are u32 and aside of that wrmsrl() already
  provides the high/low split for free.

- Remove the pointless get_cpu()/put_cpu() dance from various
  functions. Either they are called during early init where CPU is
  guaranteed to be 0 or they are already called from non preemptible
  context where smp_processor_id() can be used safely

- Simplify the convoluted check for kvmclock in the init function.

- Mark the parameter parsing function __init. No point in keeping it
  around.

- Convert to pr_info()
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Link: https://lkml.kernel.org/r/20180719205545.16512-5-pasha.tatashin@oracle.com

The return value is pointless because the wrmsr cannot fail if
KVM_FEATURE_CLOCKSOURCE or KVM_FEATURE_CLOCKSOURCE2 are set.

kvm_register_clock() is only called locally so wants to be static.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Link: https://lkml.kernel.org/r/20180719205545.16512-4-pasha.tatashin@oracle.com

There is no requirement for wall_clock data to be page aligned or page
sized.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Link: https://lkml.kernel.org/r/20180719205545.16512-3-pasha.tatashin@oracle.com

KVM clock is initialized later compared to other hypervisor clocks because
it has a dependency on the memblock allocator.

Bring it in line with other hypervisors by using memory from the BSS
instead of allocating it.

The benefits:

  - Remove ifdef from common code
  - Earlier availability of the clock
  - Remove dependency on memblock, and reduce code

The downside:

  - Static allocation of the per cpu data structures sized NR_CPUS * 64byte
    Will be addressed in follow up patches.

[ tglx: Split out from larger series ]
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Link: https://lkml.kernel.org/r/20180719205545.16512-2-pasha.tatashin@oracle.com

Pick up upstream changes to avoid conflicts

Pull PCI fixes from Bjorn Helgaas:

 - Fix crashes that happen when PHY drivers are left disabled in the V3
   Semiconductor, MediaTek, Faraday, Aardvark, DesignWare, Versatile,
   and X-Gene host controller drivers (Sergei Shtylyov)

 - Fix a NULL pointer dereference in the endpoint library configfs
   support (Kishon Vijay Abraham I)

 - Fix a race condition in Hyper-V IRQ handling (Dexuan Cui)

* tag 'pci-v4.18-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: v3-semi: Fix I/O space page leak
  PCI: mediatek: Fix I/O space page leak
  PCI: faraday: Fix I/O space page leak
  PCI: aardvark: Fix I/O space page leak
  PCI: designware: Fix I/O space page leak
  PCI: versatile: Fix I/O space page leak
  PCI: xgene: Fix I/O space page leak
  PCI: OF: Fix I/O space page leak
  PCI: endpoint: Fix NULL pointer dereference error when CONFIGFS is disabled
  PCI: hv: Disable/enable IRQs rather than BH in hv_compose_msi_msg()

Pull sound fixes from Takashi Iwai:
 "A rawmidi race fix and three trivial HD-audio quirks"

* tag 'sound-4.18-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda/realtek - Yet another Clevo P950 quirk entry
  ALSA: rawmidi: Change resized buffers atomically
  ALSA: hda/realtek - Add Panasonic CF-SZ6 headset jack quirk
  ALSA: hda: add mute led support for HP ProBook 455 G5

Pull crypto fix from Herbert Xu:
 "This fixes an allocation error-path bug in af_alg discovered by
  syzkaller"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: af_alg - Initialize sg_num_bytes in error code path

Pull networking fixes from David Miller:
 "Lots of fixes, here goes:

   1) NULL deref in qtnfmac, from Gustavo A. R. Silva.

   2) Kernel oops when fw download fails in rtlwifi, from Ping-Ke Shih.

   3) Lost completion messages in AF_XDP, from Magnus Karlsson.

   4) Correct bogus self-assignment in rhashtable, from Rishabh
      Bhatnagar.

   5) Fix regression in ipv6 route append handling, from David Ahern.

   6) Fix masking in __set_phy_supported(), from Heiner Kallweit.

   7) Missing module owner set in x_tables icmp, from Florian Westphal.

   8) liquidio's timeouts are HZ dependent, fix from Nicholas Mc Guire.

   9) Link setting fixes for sh_eth and ravb, from Vladimir Zapolskiy.

  10) Fix NULL deref when using chains in act_csum, from Davide Caratti.

  11) XDP_REDIRECT needs to check if the interface is up and whether the
      MTU is sufficient. From Toshiaki Makita.

  12) Net diag can do a double free when killing TCP_NEW_SYN_RECV
      connections, from Lorenzo Colitti.

  13) nf_defrag in ipv6 can unnecessarily hold onto dst entries for a
      full minute, delaying device unregister. From Eric Dumazet.

  14) Update MAC entries in the correct order in ixgbe, from Alexander
      Duyck.

  15) Don't leave partial mangles bpf program in jit_subprogs, from
      Daniel Borkmann.

  16) Fix pfmemalloc SKB state propagation, from Stefano Brivio.

  17) Fix ACK handling in DCTCP congestion control, from Yuchung Cheng.

  18) Use after free in tun XDP_TX, from Toshiaki Makita.

  19) Stale ipv6 header pointer in ipv6 gre code, from Prashant Bhole.

  20) Don't reuse remainder of RX page when XDP is set in mlx4, from
      Saeed Mahameed.

  21) Fix window probe handling of TCP rapair sockets, from Stefan
      Baranoff.

  22) Missing socket locking in smc_ioctl(), from Ursula Braun.

  23) IPV6_ILA needs DST_CACHE, from Arnd Bergmann.

  24) Spectre v1 fix in cxgb3, from Gustavo A. R. Silva.

  25) Two spots in ipv6 do a rol32() on a hash value but ignore the
      result. Fixes from Colin Ian King"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (176 commits)
  tcp: identify cryptic messages as TCP seq # bugs
  ptp: fix missing break in switch
  hv_netvsc: Fix napi reschedule while receive completion is busy
  MAINTAINERS: Drop inactive Vitaly Bordug's email
  net: cavium: Add fine-granular dependencies on PCI
  net: qca_spi: Fix log level if probe fails
  net: qca_spi: Make sure the QCA7000 reset is triggered
  net: qca_spi: Avoid packet drop during initial sync
  ipv6: fix useless rol32 call on hash
  ipv6: sr: fix useless rol32 call on hash
  net: sched: Using NULL instead of plain integer
  net: usb: asix: replace mii_nway_restart in resume path
  net: cxgb3_main: fix potential Spectre v1
  lib/rhashtable: consider param->min_size when setting initial table size
  net/smc: reset recv timeout after clc handshake
  net/smc: add error handling for get_user()
  net/smc: optimize consumer cursor updates
  net/nfc: Avoid stalls when nfc_alloc_send_skb() returned NULL.
  ipv6: ila: select CONFIG_DST_CACHE
  net: usb: rtl8150: demote allmulti message to dev_dbg()
  ...

Pull DeviceTree fixes from Rob Herring:

 - Fix phandle cache to work with overlays

 - Correct the default clock-frequency for QCom geni-i2c

 - Binding doc quote and spelling fixes

* tag 'devicetree-fixes-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  of: overlay: update phandle cache on overlay apply and remove
  dt-bindings: Fix unbalanced quotation marks
  dt-bindings: soc: qcom: Fix default clock-freq for qcom,geni-i2c
  dt-bindings: w1-gpio: Remove unneeded unit address
  Documentation: devicetree: tilcdc: fix spelling mistake "suppors" -> "supports"

Attempt to make cryptic TCP seq number error messages clearer by
(1) identifying the source of the message as "TCP", (2) identifying the
errors as "seq # bug", and (3) grouping the field identifiers and values
by separating them with commas.

E.g., the following message is changed from:

recvmsg bug 2: copied 73BCB6CD seq 70F17CBE rcvnxt 73BCB9AA fl 0
WARNING: CPU: 2 PID: 1501 at /linux/net/ipv4/tcp.c:1881 tcp_recvmsg+0x649/0xb90

to:

TCP recvmsg seq # bug 2: copied 73BCB6CD, seq 70F17CBE, rcvnxt 73BCB9AA, fl 0
WARNING: CPU: 2 PID: 1501 at /linux/net/ipv4/tcp.c:2011 tcp_recvmsg+0x694/0xba0
Suggested-by: N積丹尼 Dan Jacobson <jidanni@jidanni.org>
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It seems that a *break* is missing in order to avoid falling through
to the default case. Otherwise, checking *chan* makes no sense.

Fixes: 72df7a72 ("ptp: Allow reassigning calibration pin function")
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If out ring is full temporarily and receive completion cannot go out,
we may still need to reschedule napi if certain conditions are met.
Otherwise the napi poll might be stopped forever, and cause network
disconnect.

Fixes: 7426b1a5 ("netvsc: optimize receive completions")
Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The Vitaly Bordug's email bounces ("ru.mvista.com: Name or service not
known") and there was no activity (ack, review, sign) since 2009.

Cc: Vitaly Bordug <vitb@kernel.crashing.org>
Cc: Pantelis Antoniou <pantelis.antoniou@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add dependencies on PCI where necessary.

Fixes: 7e2bc7fb ("net: cavium: Drop dependency of NET_VENDOR_CAVIUM on PCI")
Signed-off-by: NAlexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Stefan Wahren says:

====================
net: qca_spi: Minor bugfixes

This patch series contains some minor bugfixes for
the qca_spi driver.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In cases the probing fails the log level of the messages should
be an error.
Signed-off-by: NStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In case the SPI thread is not running, a simple reset of sync
state won't fix the transmit timeout. We also need to wake up the kernel
thread.
Signed-off-by: NStefan Wahren <stefan.wahren@i2se.com>
Fixes: ed7d42e2 ("net: qca_spi: fix transmit queue timeout handling")
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As long as the synchronization with the QCA7000 isn't finished, we
cannot accept packets from the upper layers. So let the SPI thread
enable the TX queue after sync and avoid unwanted packet drop.
Signed-off-by: NStefan Wahren <stefan.wahren@i2se.com>
Fixes: 291ab06e ("net: qualcomm: new Ethernet over SPI driver for QCA7000")
Signed-off-by: NDavid S. Miller <davem@davemloft.net>