Commit Graph

63 Commits

Author SHA1 Message Date
Vitaly Kuznetsov 7415aea607 hyper-v: Globalize vp_index
To support implementing remote TLB flushing on Hyper-V with a hypercall
we need to make vp_index available outside of vmbus module. Rename and
globalize.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devel@linuxdriverproject.org
Link: http://lkml.kernel.org/r/20170802160921.21791-7-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10 16:50:23 +02:00
Michael Kelley 13b9abfc92 Drivers: hv: vmbus: Close timing hole that can corrupt per-cpu page
Extend the disabling of preemption to include the hypercall so that
another thread can't get the CPU and corrupt the per-cpu page used
for hypercall arguments.

Cc: <Stable@vger.kernel.org> #4.11
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 15:42:42 +02:00
K. Y. Srinivasan e546d778d6 Drivers: hv: vmbus: Get the current time from the current clocksource
The current code uses the MSR based mechanism to get the current tick.
Use the current clock source as that might be more optimal.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 15:42:42 +02:00
K. Y. Srinivasan 6c248aad81 Drivers: hv: Base autoeoi enablement based on hypervisor hints
Don't enable auto-eoi if the hypervisor recommends otherwise. This will
enable vAPIC functionality if available.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-17 15:10:49 +09:00
Stephen Hemminger 631e63a9f3 vmbus: change to per channel tasklet
Make the event handling tasklet per channel rather than per-cpu.
This allows for better fairness when getting lots of data on the same
cpu.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-14 10:20:35 -08:00
Stephen Hemminger 37cdd991fa vmbus: put related per-cpu variable together
The hv_context structure had several arrays which were per-cpu
and was allocating small structures (tasklet_struct). Instead use
a single per-cpu array.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-14 10:20:35 -08:00
Vitaly Kuznetsov d6f3609d2b Drivers: hv: restore hypervcall page cleanup before kexec
We need to cleanup the hypercall page before doing kexec/kdump or the new
kernel may crash if it tries to use it. Reuse the now-empty hv_cleanup
function renaming it to hyperv_cleanup and moving to the arch specific
code.

Fixes: 8730046c14 ("Drivers: hv vmbus: Move Hypercall page setup out of common code")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-31 11:05:58 +01:00
K. Y. Srinivasan 37e11d5c70 Drivers: hv: vmbus: Define an APIs to manage interrupt state
As part of cleaning up architecture specific code, define APIs
to manage interrupt state.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:52:49 +01:00
K. Y. Srinivasan 7297ff0ca9 Drivers: hv: vmbus: Define an API to retrieve virtual processor index
As part of cleaning up architecture specific code, define an API
to retrieve the virtual procesor index.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:52:48 +01:00
K. Y. Srinivasan 06d1d98a83 Drivers: hv: vmbus: Define APIs to manipulate the synthetic interrupt controller
As part of cleaning up architecture specific code, define APIs
to manipulate the interrupt controller state.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:51:21 +01:00
K. Y. Srinivasan 8e307bf82d Drivers: hv: vmbus: Define APIs to manipulate the event page
As part of cleaning up architecture specific code, define APIs
to manipulate the event page.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:51:21 +01:00
K. Y. Srinivasan 155e4a2f28 Drivers: hv: vmbus: Define APIs to manipulate the message page
As part of cleaning up architecture specific code, define APIs
to manipulate the message page.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:51:21 +01:00
K. Y. Srinivasan d383877db6 Drivers: hv: vmbus: Get rid of an unsused variable
The version variable while it is initialized is not used;
get rid of it.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:51:21 +01:00
K. Y. Srinivasan d5116b4091 Drivers: hv: vmbus: Restructure the clockevents code
Move the relevant code that programs the hypervisor to an architecture
specific file.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:48:03 +01:00
K. Y. Srinivasan 73638cddaa Drivers: hv: vmbus: Move the check for hypercall page setup
As part of the effort to separate out architecture specific code, move the
check for detecting if the hypercall page is setup.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:48:03 +01:00
K. Y. Srinivasan 8de8af7e08 Drivers: hv: vmbus: Move the extracting of Hypervisor version information
As part of the effort to separate out architecture specific code,
extract hypervisor version information in an architecture specific
file.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:48:03 +01:00
K. Y. Srinivasan 63ed4e0c67 Drivers: hv: vmbus: Consolidate all Hyper-V specific clocksource code
As part of the effort to separate out architecture specific code,
consolidate all Hyper-V specific clocksource code to an architecture
specific code.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20 14:48:03 +01:00
K. Y. Srinivasan 6ab42a66d2 Drivers: hv: vmbus: Move Hypercall invocation code out of common code
As part of the effort to separate out architecture specific code, move the
hypercall invocation code to an architecture specific file.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 11:44:55 +01:00
K. Y. Srinivasan 8730046c14 Drivers: hv vmbus: Move Hypercall page setup out of common code
As part of the effort to separate out architecture specific code, move the
hypercall page setup to an architecture specific file.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 11:42:07 +01:00
Vitaly Kuznetsov 523b940870 hv: make CPU offlining prevention fine-grained
Since commit e513229b4c ("Drivers: hv: vmbus: prevent cpu offlining on
newer hypervisors") cpu offlining was disabled. It is still true that we
can't offline CPUs which have VMBus channels bound to them but we may have
'free' CPUs (e.v. we booted with maxcpus= parameter and onlined CPUs after
VMBus was initialized), these CPUs may be disabled without issues.

In future, we may even allow closing CPUs which have only sub-channels
assinged to them by closing these sub-channels. All devices will continue
to work.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-10 21:46:41 +01:00
Vitaly Kuznetsov 76d36ab798 hv: switch to cpuhp state machine for synic init/cleanup
To make it possible to online/offline CPUs switch to cpuhp infrastructure
for doing hv_synic_init()/hv_synic_cleanup().

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-10 21:46:41 +01:00
Vitaly Kuznetsov 56ef6718a1 hv: don't reset hv_context.tsc_page on crash
It may happen that secondary CPUs are still alive and resetting
hv_context.tsc_page will cause a consequent crash in read_hv_clock_tsc()
as we don't check for it being not NULL there. It is safe as we're not
freeing this page anyways.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-10 21:46:40 +01:00
Vitaly Kuznetsov 3c7630d350 hv: init percpu_list in hv_synic_alloc()
Initializing hv_context.percpu_list in hv_synic_alloc() helps to prevent a
crash in percpu_channel_enq() when not all CPUs were online during
initialization and it naturally belongs there.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-10 21:46:40 +01:00
Vitaly Kuznetsov 421b8f20d3 hv: allocate synic pages for all present CPUs
It may happen that not all CPUs are online when we do hv_synic_alloc() and
in case more CPUs come online later we may try accessing these allocated
structures.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-10 21:46:40 +01:00
Thomas Gleixner a5a1d1c291 clocksource: Use a plain u64 instead of cycle_t
There is no point in having an extra type for extra confusion. u64 is
unambiguous.

Conversion was done with the following coccinelle script:

@rem@
@@
-typedef u64 cycle_t;

@fix@
typedef cycle_t;
@@
-cycle_t
+u64

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
2016-12-25 11:04:12 +01:00
Vitaly Kuznetsov 6ffc4b8535 hv: change clockevents unbind tactics
To get prepared to CPU offlining support we need co change the way how we
unbind clockevent devices. As one CPU may go online/offline multiple times
we need to bind it in hv_synic_init() and unbind it in hv_synic_cleanup().
There is an additional corner case: when we unload the module completely we
need to switch to some other clockevent mechanism before stopping VMBus or
we will hang. We can't call hv_synic_cleanup() before unloading VMBus as
we won't be able to send UNLOAD request and get a response so
hv_synic_clockevents_cleanup() has to live. Luckily, we can always call
clockevents_unbind_device(), even if it wasn't bound before and there is
no issue if we call it twice.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-06 11:10:54 +01:00
Vitaly Kuznetsov a9f61ca793 Drivers: hv: avoid vfree() on crash
When we crash from NMI context (e.g. after NMI injection from host when
'sysctl -w kernel.unknown_nmi_panic=1' is set) we hit

    kernel BUG at mm/vmalloc.c:1530!

as vfree() is denied. While the issue could be solved with in_nmi() check
instead I opted for skipping vfree on all sorts of crashes to reduce the
amount of work which can cause consequent crashes. We don't really need to
free anything on crash.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 13:05:40 +02:00
K. Y. Srinivasan d81274aae6 Drivers: hv: vmbus: Support handling messages on multiple CPUs
Starting with Windows 2012 R2, message inteerupts can be delivered
on any VCPU in the guest. Support this functionality.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-01 16:57:20 -08:00
Vitaly Kuznetsov 3ccb4fd8f4 Drivers: hv: vmbus: don't manipulate with clocksources on crash
clocksource_change_rating() involves mutex usage and can't be called
in interrupt context. It also makes sense to avoid doing redundant work
on crash.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07 21:34:12 -08:00
K. Y. Srinivasan 1b807e1011 Drivers: hv: vmbus: Cleanup vmbus_set_event()
Cleanup vmbus_set_event() by inlining the hypercall to post
the event and since the return value of vmbus_set_event() is not checked,
make it void. As part of this cleanup, get rid of the function
hv_signal_event() as it is only callled from vmbus_set_event().

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07 21:32:57 -08:00
Andrey Smetanin c35b82ef02 drivers/hv: correct tsc page sequence invalid value
Hypervisor Top Level Functional Specification v3/4 says
that TSC page sequence value = -1(0xFFFFFFFF) is used to
indicate that TSC page no longer reliable source of reference
timer. Unfortunately, we found that Windows Hyper-V guest
side implementation uses sequence value = 0 to indicate
that Tsc page no longer valid. This is clearly visible
inside Windows 2012R2 ntoskrnl.exe HvlGetReferenceTime()
function dissassembly:

HvlGetReferenceTime proc near
                 xchg    ax, ax
loc_1401C3132:
                 mov     rax, cs:HvlpReferenceTscPage
                 mov     r9d, [rax]
                 test    r9d, r9d
                 jz      short loc_1401C3176
                 rdtsc
                 mov     rcx, cs:HvlpReferenceTscPage
                 shl     rdx, 20h
                 or      rdx, rax
                 mov     rax, [rcx+8]
                 mov     rcx, cs:HvlpReferenceTscPage
                 mov     r8, [rcx+10h]
                 mul     rdx
                 mov     rax, cs:HvlpReferenceTscPage
                 add     rdx, r8
                 mov     ecx, [rax]
                 cmp     ecx, r9d
                 jnz     short loc_1401C3132
                 jmp     short loc_1401C3184
loc_1401C3176:
                 mov     ecx, 40000020h
                 rdmsr
                 shl     rdx, 20h
                 or      rdx, rax
loc_1401C3184:
                 mov     rax, rdx
                 retn
HvlGetReferenceTime endp

This patch aligns Tsc page invalid sequence value with
Windows Hyper-V guest implementation which is more
compatible with both Hyper-V hypervisor and KVM hypervisor.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: "K. Y. Srinivasan" <kys@microsoft.com>
CC: Haiyang Zhang <haiyangz@microsoft.com>
CC: Vitaly Kuznetsov <vkuznets@redhat.com>

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14 19:15:05 -08:00
Jake Oshins a108393dbf drivers:hv: Export the API to invoke a hypercall on Hyper-V
This patch exposes the function that hv_vmbus.ko uses to make hypercalls.  This
is necessary for retargeting an interrupt when it is given a new affinity.

Since we are exporting this API, rename the API as it will be visible outside
the hv.c file.

Signed-off-by: Jake Oshins <jakeo@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14 19:12:21 -08:00
Sudip Mukherjee 9220e39b5c Drivers: hv: vmbus: fix build warning
We were getting build warning about unused variable "tsc_msr" and
"va_tsc" while building for i386 allmodconfig.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14 13:34:50 -08:00
K. Y. Srinivasan ca9357bd26 Drivers: hv: vmbus: Implement a clocksource based on the TSC page
The current Hyper-V clock source is based on the per-partition reference counter
and this counter is being accessed via s synthetic MSR - HV_X64_MSR_TIME_REF_COUNT.
Hyper-V has a more efficient way of computing the per-partition reference
counter value that does not involve reading a synthetic MSR. We implement
a time source based on this mechanism.

Tested-by: Vivek Yadav <vyadav@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-05 11:44:29 -07:00
Viresh Kumar bc609cb47f drivers/hv: Migrate to new 'set-state' interface
Migrate hv driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.

This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.

Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: devel@linuxdriverproject.org
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-05 11:44:29 -07:00
K. Y. Srinivasan 9f01ec5345 Drivers: hv: vmbus: Improve the CPU affiliation for channels
The current code tracks the assigned CPUs within a NUMA node in the context of
the primary channel. So, if we have a VM with a single NUMA node with 8 VCPUs, we may
end up unevenly distributing the channel load. Fix the issue by tracking affiliations
globally.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-05 11:41:31 -07:00
Vitaly Kuznetsov d7646eaa76 Drivers: hv: don't do hypercalls when hypercall_page is NULL
At the very late stage of kexec a driver (which are not being unloaded) can
try to post a message or signal an event. This will crash the kernel as we
already did hv_cleanup() and the hypercall page is NULL.

Move all common (between 32 and 64 bit code) declarations to the beginning
of the do_hypercall() function. Unfortunately we have to write the
!hypercall_page check twice to not mix declarations and code.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-04 22:25:29 -07:00
Vitaly Kuznetsov 06210b42f3 Drivers: hv: vmbus: remove hv_synic_free_cpu() call from hv_synic_cleanup()
We already have hv_synic_free() which frees all per-cpu pages for all
CPUs, let's remove the hv_synic_free_cpu() call from hv_synic_cleanup()
so it will be possible to do separate cleanup (writing to MSRs) and final
freeing. This is going to be used to assist kexec.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-04 22:25:28 -07:00
Vitaly Kuznetsov e086748c65 Drivers: hv: vmbus: Teardown clockevent devices on module unload
Newly introduced clockevent devices made it impossible to unload hv_vmbus
module as clockevents_config_and_register() takes additional reverence to
the module. To make it possible again we do the following:
- avoid setting dev->owner for clockevent devices;
- implement hv_synic_clockevents_cleanup() doing clockevents_unbind_device();
- call it from vmbus_exit().

In theory hv_synic_clockevents_cleanup() can be merged with hv_synic_cleanup(),
however, we call hv_synic_cleanup() from smp_call_function_single() and this
doesn't work for clockevents_unbind_device() as it does such call on its own. I
opted for a separate function.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-01 19:30:07 -08:00
Vitaly Kuznetsov e72e7ac583 drivers: hv: vmbus: Teardown synthetic interrupt controllers on module unload
SynIC has to be switched off when we unload the module, otherwise registered
memory pages can get corrupted after (as Hyper-V host still writes there) and
we see the following crashes for random processes:

[   89.116774] BUG: Bad page map in process sh  pte:4989c716 pmd:36f81067
[   89.159454] addr:0000000000437000 vm_flags:00000875 anon_vma:          (null) mapping:ffff88007bba55a0 index:37
[   89.226146] vma->vm_ops->fault: filemap_fault+0x0/0x410
[   89.257776] vma->vm_file->f_op->mmap: generic_file_mmap+0x0/0x60
[   89.297570] CPU: 0 PID: 215 Comm: sh Tainted: G    B          3.19.0-rc5_bug923184+ #488
[   89.353738] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090006  05/23/2012
[   89.409138]  0000000000000000 000000004e083d7b ffff880036e9fa18 ffffffff81a68d31
[   89.468724]  0000000000000000 0000000000437000 ffff880036e9fa68 ffffffff811a1e3a
[   89.519233]  000000004989c716 0000000000000037 ffffea0001edc340 0000000000437000
[   89.575751] Call Trace:
[   89.591060]  [<ffffffff81a68d31>] dump_stack+0x45/0x57
[   89.625164]  [<ffffffff811a1e3a>] print_bad_pte+0x1aa/0x250
[   89.667234]  [<ffffffff811a2c95>] vm_normal_page+0x55/0xa0
[   89.703818]  [<ffffffff811a3105>] unmap_page_range+0x425/0x8a0
[   89.737982]  [<ffffffff811a3601>] unmap_single_vma+0x81/0xf0
[   89.780385]  [<ffffffff81184320>] ? lru_deactivate_fn+0x190/0x190
[   89.820130]  [<ffffffff811a4131>] unmap_vmas+0x51/0xa0
[   89.860168]  [<ffffffff811ad12c>] exit_mmap+0xac/0x1a0
[   89.890588]  [<ffffffff810763c3>] mmput+0x63/0x100
[   89.919205]  [<ffffffff811eba48>] flush_old_exec+0x3f8/0x8b0
[   89.962135]  [<ffffffff8123b5bb>] load_elf_binary+0x32b/0x1260
[   89.998581]  [<ffffffff811a14f2>] ? get_user_pages+0x52/0x60

hv_synic_cleanup() function exists but noone calls it now. Do the following:
- call hv_synic_cleanup() on each cpu from vmbus_exit();
- write global disable bit through MSR;
- use hv_synic_free_cpu() to avoid memory leask and code duplication.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-01 19:29:05 -08:00
K. Y. Srinivasan 4061ed9e2a Drivers: hv: vmbus: Implement a clockevent device
Implement a clockevent device based on the timer support available on
Hyper-V.
In this version of the patch I have addressed Jason's review comments.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-25 09:17:57 -08:00
K. Y. Srinivasan b29ef3546a Drivers: hv: vmbus: Cleanup hv_post_message()
Minimize failures in this function by pre-allocating the buffer
for posting messages. The hypercall for posting the message can fail
for a number of reasons:

        1. Transient resource related issues
        2. Buffer alignment
        3. Buffer cannot span a page boundry

We address issues 2 and 3 by preallocating a per-cpu page for the buffer.
Transient resource related failures are handled by retrying by the callers
of this function.

This patch is based on the investigation
done by Dexuan Cui <decui@microsoft.com>.

I would like to thank Sitsofe Wheeler <sitsofe@yahoo.com>
for reporting the issue and helping in debuggging.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Cc: <stable@vger.kernel.org>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-23 23:31:21 -07:00
K. Y. Srinivasan 3a28fa35d6 Drivers: hv: vmbus: Implement per-CPU mapping of relid to channel
Currently the mapping of the relID to channel is done under the protection of a
single spin lock. Starting with ws2012, each channel is bound to a specific VCPU
in the guest. Use this binding to eliminate the spin lock by setting up
per-cpu state for mapping relId to the channel.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-03 19:24:26 -04:00
Rashika Kheria 8712954d15 drivers: hv: Mark the function hv_synic_free_cpu() as static in hv.c
This patch marks the function hv_synic_free_cpu() as static in hv.c
because it is not used outside this file.

Thus, it also eliminates the following warning in hv.c:
drivers/hv/hv.c:304:6: warning: no previous prototype for ‘hv_synic_free_cpu’ [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-18 16:41:52 -08:00
Felipe Pena fdf91dae6f drivers: hv: Fix wrong check for synic_event_page
The check for calling free_page() on hv_context.synic_event_page[cpu] is the
same for hv_context.synic_message_page[cpu], like a copy-paste error.

Signed-off-by: Felipe Pena <felipensp@gmail.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-16 14:00:09 -07:00
Jason Wang 2608fb6531 drivers: hv: allocate synic structures before hv_synic_init()
We currently allocate synic structures in hv_sync_init(), but there's no way for
the driver to know about the allocation failure and it may continue to use the
uninitialized pointers. Solve this by introducing helpers for allocating and
freeing and doing the allocation before the on_each_cpu() call in
vmbus_bus_init().

Cc: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-24 16:24:17 -07:00
Zhang Yanfei 3334948428 driver: hv: remove cast for kmalloc return value
remove cast for kmalloc return value.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-15 11:22:24 -07:00
K. Y. Srinivasan 302a3c0f27 Drivers: hv: vmbus: Use the new infrastructure for delivering VMBUS interrupts
Use the infrastructure for delivering VMBUS interrupts using a
special vector. With this patch, we can now properly handle
the VMBUS interrupts that can be delivered on any CPU. Also,
turn on interrupt load balancing as well.

This patch requires the infrastructure that was implemented in the patch:
X86: Handle Hyper-V vmbus interrupts as special hypervisor interrupts

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-27 10:15:53 -08:00
K. Y. Srinivasan 3bacaf0ce1 Drivers: hv: Cleanup and consolidate reporting of build/version info
Now, cleanup and consolidate reporting of host and vmbus version numbers.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-17 11:41:50 -08:00
K. Y. Srinivasan 5fbebb2d20 Drivers: hv: Capture the host build information
Capture the host build information so it can be presented along with the
negotiated vmbus version information.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-17 11:41:49 -08:00