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  1. 11 6月, 2020 1 次提交
  3. 03 6月, 2020 2 次提交
    • C
      mm: remove the pgprot argument to __vmalloc · 88dca4ca
      由 Christoph Hellwig 提交于 
      The pgprot argument to __vmalloc is always PAGE_KERNEL now, so remove it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com> [hyperv]
Acked-by: Gao Xiang <xiang@kernel.org> [erofs]
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NWei Liu <wei.liu@kernel.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200414131348.444715-22-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      88dca4ca
    • C
      x86/hyperv: use vmalloc_exec for the hypercall page · 78bb17f7
      由 Christoph Hellwig 提交于 
      Patch series "decruft the vmalloc API", v2.

Peter noticed that with some dumb luck you can toast the kernel address
space with exported vmalloc symbols.

I used this as an opportunity to decruft the vmalloc.c API and make it
much more systematic.  This also removes any chance to create vmalloc
mappings outside the designated areas or using executable permissions
from modules.  Besides that it removes more than 300 lines of code.

This patch (of 29):

Use the designated helper for allocating executable kernel memory, and
remove the now unused PAGE_KERNEL_RX define.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Acked-by: NWei Liu <wei.liu@kernel.org>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Gao Xiang <xiang@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lkml.kernel.org/r/20200414131348.444715-1-hch@lst.de
Link: http://lkml.kernel.org/r/20200414131348.444715-2-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      78bb17f7
  5. 13 5月, 2020 1 次提交
    • V
      x86/hyperv: Properly suspend/resume reenlightenment notifications · 38dce419
      由 Vitaly Kuznetsov 提交于 
      Errors during hibernation with reenlightenment notifications enabled were
reported:

 [   51.730435] PM: hibernation entry
 [   51.737435] PM: Syncing filesystems ...
 ...
 [   54.102216] Disabling non-boot CPUs ...
 [   54.106633] smpboot: CPU 1 is now offline
 [   54.110006] unchecked MSR access error: WRMSR to 0x40000106 (tried to
     write 0x47c72780000100ee) at rIP: 0xffffffff90062f24
     native_write_msr+0x4/0x20)
 [   54.110006] Call Trace:
 [   54.110006]  hv_cpu_die+0xd9/0xf0
 ...

Normally, hv_cpu_die() just reassigns reenlightenment notifications to some
other CPU when the CPU receiving them goes offline. Upon hibernation, there
is no other CPU which is still online so cpumask_any_but(cpu_online_mask)
returns >= nr_cpu_ids and using it as hv_vp_index index is incorrect.
Disable the feature when cpumask_any_but() fails.

Also, as we now disable reenlightenment notifications upon hibernation we
need to restore them on resume. Check if hv_reenlightenment_cb was
previously set and restore from hv_resume().
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: NDexuan Cui <decui@microsoft.com>
Reviewed-by: NTianyu Lan <Tianyu.Lan@microsoft.com>
Link: https://lore.kernel.org/r/20200512160153.134467-1-vkuznets@redhat.comSigned-off-by: NWei Liu <wei.liu@kernel.org>
      38dce419
  7. 21 4月, 2020 1 次提交
    • D
      x86/hyperv: Suspend/resume the VP assist page for hibernation · 421f090c
      由 Dexuan Cui 提交于 
      Unlike the other CPUs, CPU0 is never offlined during hibernation, so in the
resume path, the "new" kernel's VP assist page is not suspended (i.e. not
disabled), and later when we jump to the "old" kernel, the page is not
properly re-enabled for CPU0 with the allocated page from the old kernel.

So far, the VP assist page is used by hv_apic_eoi_write(), and is also
used in the case of nested virtualization (running KVM atop Hyper-V).

For hv_apic_eoi_write(), when the page is not properly re-enabled,
hvp->apic_assist is always 0, so the HV_X64_MSR_EOI MSR is always written.
This is not ideal with respect to performance, but Hyper-V can still
correctly handle this according to the Hyper-V spec; nevertheless, Linux
still must update the Hyper-V hypervisor with the correct VP assist page
to prevent Hyper-V from writing to the stale page, which causes guest
memory corruption and consequently may have caused the hangs and triple
faults seen during non-boot CPUs resume.

Fix the issue by calling hv_cpu_die()/hv_cpu_init() in the syscore ops.
Without the fix, hibernation can fail at a rate of 1/300 ~ 1/500.
With the fix, hibernation can pass a long-haul test of 2000 runs.

In the case of nested virtualization, disabling/reenabling the assist
page upon hibernation may be unsafe if there are active L2 guests.
It looks KVM should be enhanced to abort the hibernation request if
there is any active L2 guest.

Fixes: 05bd330a ("x86/hyperv: Suspend/resume the hypercall page for hibernation")
Cc: stable@vger.kernel.org
Signed-off-by: NDexuan Cui <decui@microsoft.com>
Link: https://lore.kernel.org/r/1587437171-2472-1-git-send-email-decui@microsoft.comSigned-off-by: NWei Liu <wei.liu@kernel.org>
      421f090c
  9. 12 4月, 2020 1 次提交
  11. 01 2月, 2020 1 次提交
  13. 22 11月, 2019 2 次提交
    • D
      x86/hyperv: Implement hv_is_hibernation_supported() · b96f8653
      由 Dexuan Cui 提交于 
      The API will be used by the hv_balloon and hv_vmbus drivers.

Balloon up/down and hot-add of memory must not be active if the user
wants the Linux VM to support hibernation, because they are incompatible
with hibernation according to Hyper-V team, e.g. upon suspend the
balloon VSP doesn't save any info about the ballooned-out pages (if any);
so, after Linux resumes, Linux balloon VSC expects that the VSP will
return the pages if Linux is under memory pressure, but the VSP will
never do that, since the VSP thinks it never stole the pages from the VM.

So, if the user wants Linux VM to support hibernation, Linux must forbid
balloon up/down and hot-add, and the only functionality of the balloon VSC
driver is reporting the VM's memory pressure to the host.

Ideally, when Linux detects that the user wants it to support hibernation,
the balloon VSC should tell the VSP that it does not support ballooning
and hot-add. However, the current version of the VSP requires the VSC
should support these capabilities, otherwise the capability negotiation
fails and the VSC can not load at all, so with the later changes to the
VSC driver, Linux VM still reports to the VSP that the VSC supports these
capabilities, but the VSC ignores the VSP's requests of balloon up/down
and hot add, and reports an error to the VSP, when applicable. BTW, in
the future the balloon VSP driver will allow the VSC to not support the
capabilities of balloon up/down and hot add.

The ACPI S4 state is not a must for hibernation to work, because Linux is
able to hibernate as long as the system can shut down. However in practice
we decide to artificially use the presence of the virtual ACPI S4 state as
an indicator of the user's intent of using hibernation, because Linux VM
must find a way to know if the user wants to use the hibernation feature
or not.

By default, Hyper-V does not enable the virtual ACPI S4 state; on recent
Hyper-V hosts (e.g. RS5, 19H1), the administrator is able to enable the
state for a VM by WMI commands.

Once all the vmbus and VSC patches for the hibernation feature are
accepted, an extra patch will be submitted to forbid hibernation if the
virtual ACPI S4 state is absent, i.e. hv_is_hibernation_supported() is
false.
Signed-off-by: NDexuan Cui <decui@microsoft.com>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NSasha Levin <sashal@kernel.org>
      b96f8653
    • H
      x86: hv: Add function to allocate zeroed page for Hyper-V · fa36dcdf
      由 Himadri Pandya 提交于 
      Hyper-V assumes page size to be 4K. While this assumption holds true on
x86 architecture, it might not  be true for ARM64 architecture. Hence
define hyper-v specific function to allocate a zeroed page which can
have a different implementation on ARM64 architecture to handle the
conflict between hyper-v's assumed page size and actual guest page size.
Signed-off-by: NHimadri Pandya <himadri18.07@gmail.com>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
      fa36dcdf
  15. 15 11月, 2019 1 次提交
    • M
      x86/hyperv: Initialize clockevents earlier in CPU onlining · 4df4cb9e
      由 Michael Kelley 提交于 
      Hyper-V has historically initialized stimer-based clockevents late in the
process of onlining a CPU because clockevents depend on stimer
interrupts. In the original Hyper-V design, stimer interrupts generate a
VMbus message, so the VMbus machinery must be running first, and VMbus
can't be initialized until relatively late. On x86/64, LAPIC timer based
clockevents are used during early initialization before VMbus and
stimer-based clockevents are ready, and again during CPU offlining after
the stimer clockevents have been shut down.

Unfortunately, this design creates problems when offlining CPUs for
hibernation or other purposes. stimer-based clockevents are shut down
relatively early in the offlining process, so clockevents_unbind_device()
must be used to fallback to the LAPIC-based clockevents for the remainder
of the offlining process.  Furthermore, the late initialization and early
shutdown of stimer-based clockevents doesn't work well on ARM64 since there
is no other timer like the LAPIC to fallback to. So CPU onlining and
offlining doesn't work properly.

Fix this by recognizing that stimer Direct Mode is the normal path for
newer versions of Hyper-V on x86/64, and the only path on other
architectures. With stimer Direct Mode, stimer interrupts don't require any
VMbus machinery. stimer clockevents can be initialized and shut down
consistent with how it is done for other clockevent devices. While the old
VMbus-based stimer interrupts must still be supported for backward
compatibility on x86, that mode of operation can be treated as legacy.

So add a new Hyper-V stimer entry in the CPU hotplug state list, and use
that new state when in Direct Mode. Update the Hyper-V clocksource driver
to allocate and initialize stimer clockevents earlier during boot. Update
Hyper-V initialization and the VMbus driver to use this new design. As a
result, the LAPIC timer is no longer used during boot or CPU
onlining/offlining and clockevents_unbind_device() is not called.  But
retain the old design as a legacy implementation for older versions of
Hyper-V that don't support Direct Mode.
Signed-off-by: NMichael Kelley <mikelley@microsoft.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NDexuan Cui <decui@microsoft.com>
Reviewed-by: NDexuan Cui <decui@microsoft.com>
Link: https://lkml.kernel.org/r/1573607467-9456-1-git-send-email-mikelley@microsoft.com
      4df4cb9e
  17. 23 8月, 2019 1 次提交
  19. 22 7月, 2019 1 次提交
  21. 19 7月, 2019 1 次提交
    • D
      x86/hyper-v: Zero out the VP ASSIST PAGE on allocation · e320ab3c
      由 Dexuan Cui 提交于 
      The VP ASSIST PAGE is an "overlay" page (see Hyper-V TLFS's Section
5.2.1 "GPA Overlay Pages" for the details) and here is an excerpt:

"The hypervisor defines several special pages that "overlay" the guest's
 Guest Physical Addresses (GPA) space. Overlays are addressed GPA but are
 not included in the normal GPA map maintained internally by the hypervisor.
 Conceptually, they exist in a separate map that overlays the GPA map.

 If a page within the GPA space is overlaid, any SPA page mapped to the
 GPA page is effectively "obscured" and generally unreachable by the
 virtual processor through processor memory accesses.

 If an overlay page is disabled, the underlying GPA page is "uncovered",
 and an existing mapping becomes accessible to the guest."

SPA = System Physical Address = the final real physical address.

When a CPU (e.g. CPU1) is onlined, hv_cpu_init() allocates the VP ASSIST
PAGE and enables the EOI optimization for this CPU by writing the MSR
HV_X64_MSR_VP_ASSIST_PAGE. From now on, hvp->apic_assist belongs to the
special SPA page, and this CPU *always* uses hvp->apic_assist (which is
shared with the hypervisor) to decide if it needs to write the EOI MSR.

When a CPU is offlined then on the outgoing CPU:
1. hv_cpu_die() disables the EOI optimizaton for this CPU, and from
   now on hvp->apic_assist belongs to the original "normal" SPA page;
2. the remaining work of stopping this CPU is done
3. this CPU is completely stopped.

Between 1 and 3, this CPU can still receive interrupts (e.g. reschedule
IPIs from CPU0, and Local APIC timer interrupts), and this CPU *must* write
the EOI MSR for every interrupt received, otherwise the hypervisor may not
deliver further interrupts, which may be needed to completely stop the CPU.

So, after the EOI optimization is disabled in hv_cpu_die(), it's required
that the hvp->apic_assist's bit0 is zero, which is not guaranteed by the
current allocation mode because it lacks __GFP_ZERO. As a consequence the
bit might be set and interrupt handling would not write the EOI MSR causing
interrupt delivery to become stuck.

Add the missing __GFP_ZERO to the allocation.

Note 1: after the "normal" SPA page is allocted and zeroed out, neither the
hypervisor nor the guest writes into the page, so the page remains with
zeros.

Note 2: see Section 10.3.5 "EOI Assist" for the details of the EOI
optimization. When the optimization is enabled, the guest can still write
the EOI MSR register irrespective of the "No EOI required" value, but
that's slower than the optimized assist based variant.

Fixes: ba696429 ("x86/hyper-v: Implement EOI assist")
Signed-off-by: NDexuan Cui <decui@microsoft.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/ <PU1P153MB0169B716A637FABF07433C04BFCB0@PU1P153MB0169.APCP153.PROD.OUTLOOK.COM
      e320ab3c
  23. 03 7月, 2019 1 次提交
    • M
      clocksource/drivers: Continue making Hyper-V clocksource ISA agnostic · dd2cb348
      由 Michael Kelley 提交于 
      Continue consolidating Hyper-V clock and timer code into an ISA
independent Hyper-V clocksource driver.

Move the existing clocksource code under drivers/hv and arch/x86 to the new
clocksource driver while separating out the ISA dependencies. Update
Hyper-V initialization to call initialization and cleanup routines since
the Hyper-V synthetic clock is not independently enumerated in ACPI.

Update Hyper-V clocksource users in KVM and VDSO to get definitions from
the new include file.

No behavior is changed and no new functionality is added.
Suggested-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NMichael Kelley <mikelley@microsoft.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Cc: "bp@alien8.de" <bp@alien8.de>
Cc: "will.deacon@arm.com" <will.deacon@arm.com>
Cc: "catalin.marinas@arm.com" <catalin.marinas@arm.com>
Cc: "mark.rutland@arm.com" <mark.rutland@arm.com>
Cc: "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org>
Cc: "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>
Cc: "linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>
Cc: "olaf@aepfle.de" <olaf@aepfle.de>
Cc: "apw@canonical.com" <apw@canonical.com>
Cc: "jasowang@redhat.com" <jasowang@redhat.com>
Cc: "marcelo.cerri@canonical.com" <marcelo.cerri@canonical.com>
Cc: Sunil Muthuswamy <sunilmut@microsoft.com>
Cc: KY Srinivasan <kys@microsoft.com>
Cc: "sashal@kernel.org" <sashal@kernel.org>
Cc: "vincenzo.frascino@arm.com" <vincenzo.frascino@arm.com>
Cc: "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>
Cc: "linux-mips@vger.kernel.org" <linux-mips@vger.kernel.org>
Cc: "linux-kselftest@vger.kernel.org" <linux-kselftest@vger.kernel.org>
Cc: "arnd@arndb.de" <arnd@arndb.de>
Cc: "linux@armlinux.org.uk" <linux@armlinux.org.uk>
Cc: "ralf@linux-mips.org" <ralf@linux-mips.org>
Cc: "paul.burton@mips.com" <paul.burton@mips.com>
Cc: "daniel.lezcano@linaro.org" <daniel.lezcano@linaro.org>
Cc: "salyzyn@android.com" <salyzyn@android.com>
Cc: "pcc@google.com" <pcc@google.com>
Cc: "shuah@kernel.org" <shuah@kernel.org>
Cc: "0x7f454c46@gmail.com" <0x7f454c46@gmail.com>
Cc: "linux@rasmusvillemoes.dk" <linux@rasmusvillemoes.dk>
Cc: "huw@codeweavers.com" <huw@codeweavers.com>
Cc: "sfr@canb.auug.org.au" <sfr@canb.auug.org.au>
Cc: "pbonzini@redhat.com" <pbonzini@redhat.com>
Cc: "rkrcmar@redhat.com" <rkrcmar@redhat.com>
Cc: "kvm@vger.kernel.org" <kvm@vger.kernel.org>
Link: https://lkml.kernel.org/r/1561955054-1838-3-git-send-email-mikelley@microsoft.com
      dd2cb348
  25. 05 6月, 2019 1 次提交
  27. 21 3月, 2019 1 次提交
  29. 07 3月, 2019 1 次提交
    • K
      x86/hyperv: Fix kernel panic when kexec on HyperV · 179fb36a
      由 Kairui Song 提交于 
      After commit 68bb7bfb ("X86/Hyper-V: Enable IPI enlightenments"),
kexec fails with a kernel panic:

kexec_core: Starting new kernel
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v3.0 03/02/2018
RIP: 0010:0xffffc9000001d000

Call Trace:
 ? __send_ipi_mask+0x1c6/0x2d0
 ? hv_send_ipi_mask_allbutself+0x6d/0xb0
 ? mp_save_irq+0x70/0x70
 ? __ioapic_read_entry+0x32/0x50
 ? ioapic_read_entry+0x39/0x50
 ? clear_IO_APIC_pin+0xb8/0x110
 ? native_stop_other_cpus+0x6e/0x170
 ? native_machine_shutdown+0x22/0x40
 ? kernel_kexec+0x136/0x156

That happens if hypercall based IPIs are used because the hypercall page is
reset very early upon kexec reboot, but kexec sends IPIs to stop CPUs,
which invokes the hypercall and dereferences the unusable page.

To fix his, reset hv_hypercall_pg to NULL before the page is reset to avoid
any misuse, IPI sending will fall back to the non hypercall based
method. This only happens on kexec / kdump so just setting the pointer to
NULL is good enough.

Fixes: 68bb7bfb ("X86/Hyper-V: Enable IPI enlightenments")
Signed-off-by: NKairui Song <kasong@redhat.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: devel@linuxdriverproject.org
Link: https://lkml.kernel.org/r/20190306111827.14131-1-kasong@redhat.com
      179fb36a
  31. 01 3月, 2019 1 次提交
  33. 28 9月, 2018 1 次提交
  35. 08 7月, 2018 1 次提交
  37. 06 7月, 2018 1 次提交
  39. 03 7月, 2018 1 次提交
    • M
      Drivers: hv: vmbus: Make TLFS #define names architecture neutral · 7dc9b6b8
      由 Michael Kelley 提交于 
      The Hyper-V feature and hint flags in hyperv-tlfs.h are all defined
with the string "X64" in the name.  Some of these flags are indeed
x86/x64 specific, but others are not.  For the ones that are used
in architecture independent Hyper-V driver code, or will be used in
the upcoming support for Hyper-V for ARM64, this patch removes the
"X64" from the name.

This patch changes the flags that are currently known to be
used on multiple architectures. Hyper-V for ARM64 is still a
work-in-progress and the Top Level Functional Spec (TLFS) has not
been separated into x86/x64 and ARM64 areas.  So additional flags
may need to be updated later.

This patch only changes symbol names.  There are no functional
changes.
Signed-off-by: NMichael Kelley <mikelley@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      7dc9b6b8
  41. 19 5月, 2018 3 次提交
  43. 29 3月, 2018 2 次提交
  45. 31 1月, 2018 5 次提交
    • V
      x86/irq: Count Hyper-V reenlightenment interrupts · 51d4e5da
      由 Vitaly Kuznetsov 提交于 
      Hyper-V reenlightenment interrupts arrive when the VM is migrated, While
they are not interesting in general it's important when L2 nested guests
are running.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: kvm@vger.kernel.org
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: "Michael Kelley (EOSG)" <Michael.H.Kelley@microsoft.com>
Cc: Roman Kagan <rkagan@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: devel@linuxdriverproject.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Cathy Avery <cavery@redhat.com>
Cc: Mohammed Gamal <mmorsy@redhat.com>
Link: https://lkml.kernel.org/r/20180124132337.30138-6-vkuznets@redhat.com
      51d4e5da
    • V
      x86/hyperv: Redirect reenlightment notifications on CPU offlining · e7c4e36c
      由 Vitaly Kuznetsov 提交于 
      It is very unlikely for CPUs to get offlined when running on Hyper-V as
there is a protection in the vmbus module which prevents it when the guest
has any VMBus devices assigned. This, however, may change in future if an
option to reassign an already active channel will be added. It is also
possible to run without any Hyper-V devices or to have a CPU with no
assigned channels.

Reassign reenlightenment notifications to some other active CPU when the
CPU which is assigned to them goes offline.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: kvm@vger.kernel.org
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: "Michael Kelley (EOSG)" <Michael.H.Kelley@microsoft.com>
Cc: Roman Kagan <rkagan@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: devel@linuxdriverproject.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Cathy Avery <cavery@redhat.com>
Cc: Mohammed Gamal <mmorsy@redhat.com>
Link: https://lkml.kernel.org/r/20180124132337.30138-5-vkuznets@redhat.com
      e7c4e36c
    • V
      x86/hyperv: Reenlightenment notifications support · 93286261
      由 Vitaly Kuznetsov 提交于 
      Hyper-V supports Live Migration notification. This is supposed to be used
in conjunction with TSC emulation: when a VM is migrated to a host with
different TSC frequency for some short period the host emulates the
accesses to TSC and sends an interrupt to notify about the event. When the
guest is done updating everything it can disable TSC emulation and
everything will start working fast again.

These notifications weren't required until now as Hyper-V guests are not
supposed to use TSC as a clocksource: in Linux the TSC is even marked as
unstable on boot. Guests normally use 'tsc page' clocksource and host
updates its values on migrations automatically.

Things change when with nested virtualization: even when the PV
clocksources (kvm-clock or tsc page) are passed through to the nested
guests the TSC frequency and frequency changes need to be know..

Hyper-V Top Level Functional Specification (as of v5.0b) wrongly specifies
EAX:BIT(12) of CPUID:0x40000009 as the feature identification bit. The
right one to check is EAX:BIT(13) of CPUID:0x40000003. I was assured that
the fix in on the way.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: kvm@vger.kernel.org
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: "Michael Kelley (EOSG)" <Michael.H.Kelley@microsoft.com>
Cc: Roman Kagan <rkagan@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: devel@linuxdriverproject.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Cathy Avery <cavery@redhat.com>
Cc: Mohammed Gamal <mmorsy@redhat.com>
Link: https://lkml.kernel.org/r/20180124132337.30138-4-vkuznets@redhat.com
      93286261
    • V
      x86/hyperv: Add a function to read both TSC and TSC page value simulateneously · e2768eaa
      由 Vitaly Kuznetsov 提交于 
      This is going to be used from KVM code where both TSC and TSC page value
are needed.

Nothing is supposed to use the function when Hyper-V code is compiled out,
just BUG().
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: kvm@vger.kernel.org
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: "Michael Kelley (EOSG)" <Michael.H.Kelley@microsoft.com>
Cc: Roman Kagan <rkagan@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: devel@linuxdriverproject.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Cathy Avery <cavery@redhat.com>
Cc: Mohammed Gamal <mmorsy@redhat.com>
Link: https://lkml.kernel.org/r/20180124132337.30138-3-vkuznets@redhat.com
      e2768eaa
    • V
      x86/hyperv: Check for required priviliges in hyperv_init() · 89a8f6d4
      由 Vitaly Kuznetsov 提交于 
      In hyperv_init() its presumed that it always has access to VP index and
hypercall MSRs while according to the specification it should be checked if
it's allowed to access the corresponding MSRs before accessing them.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: kvm@vger.kernel.org
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: "Michael Kelley (EOSG)" <Michael.H.Kelley@microsoft.com>
Cc: Roman Kagan <rkagan@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: devel@linuxdriverproject.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Cathy Avery <cavery@redhat.com>
Cc: Mohammed Gamal <mmorsy@redhat.com>
Link: https://lkml.kernel.org/r/20180124132337.30138-2-vkuznets@redhat.com
      89a8f6d4
  47. 10 1月, 2018 1 次提交
  49. 10 11月, 2017 1 次提交
  51. 31 10月, 2017 1 次提交
  53. 10 10月, 2017 1 次提交
  55. 11 8月, 2017 1 次提交
    • V
      x86/hyper-v: Use hypercall for remote TLB flush · 2ffd9e33
      由 Vitaly Kuznetsov 提交于 
      Hyper-V host can suggest us to use hypercall for doing remote TLB flush,
this is supposed to work faster than IPIs.

Implementation details: to do HvFlushVirtualAddress{Space,List} hypercalls
we need to put the input somewhere in memory and we don't really want to
have memory allocation on each call so we pre-allocate per cpu memory areas
on boot.

pv_ops patching is happening very early so we need to separate
hyperv_setup_mmu_ops() and hyper_alloc_mmu().

It is possible and easy to implement local TLB flushing too and there is
even a hint for that. However, I don't see a room for optimization on the
host side as both hypercall and native tlb flush will result in vmexit. The
hint is also not set on modern Hyper-V versions.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: NStephen 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/20170802160921.21791-8-vkuznets@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      2ffd9e33
  57. 10 8月, 2017 2 次提交
  59. 17 3月, 2017 1 次提交