Commit Graph

36266 Commits

Author SHA1 Message Date
Thomas Gleixner
445d3595ab x86/pci: Reducde #ifdeffery in PCI init code
Adding a function call before the first #ifdef in arch_pci_init() triggers
a 'mixed declarations and code' warning if PCI_DIRECT is enabled.

Use stub functions and move the #ifdeffery to the header file where it is
not in the way.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200826112332.767707340@linutronix.de
2020-09-16 16:52:35 +02:00
Thomas Gleixner
bb733e4336 x86/irq: Move apic_post_init() invocation to one place
No point to call it from both 32bit and 64bit implementations of
default_setup_apic_routing(). Move it to the caller.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200826112332.658496557@linutronix.de
2020-09-16 16:52:35 +02:00
Thomas Gleixner
9006c133a4 x86/msi: Use generic MSI domain ops
pci_msi_get_hwirq() and pci_msi_set_desc are not longer special. Enable the
generic MSI domain ops in the core and PCI MSI code unconditionally and get
rid of the x86 specific implementations in the X86 MSI code and in the
hyperv PCI driver.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200826112332.564274859@linutronix.de
2020-09-16 16:52:35 +02:00
Thomas Gleixner
3b9c1d377d x86/msi: Consolidate MSI allocation
Convert the interrupt remap drivers to retrieve the pci device from the msi
descriptor and use info::hwirq.

This is the first step to prepare x86 for using the generic MSI domain ops.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20200826112332.466405395@linutronix.de
2020-09-16 16:52:35 +02:00
Thomas Gleixner
dfb9eb7cf6 PCI/MSI: Rework pci_msi_domain_calc_hwirq()
Retrieve the PCI device from the msi descriptor instead of doing so at the
call sites.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200826112332.352583299@linutronix.de
2020-09-16 16:52:34 +02:00
Thomas Gleixner
0f5cbdaf20 x86/irq: Consolidate UV domain allocation
Move the UV specific fields into their own struct for readability sake. Get
rid of the #ifdeffery as it does not matter at all whether the alloc info
is a couple of bytes longer or not.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200826112332.255792469@linutronix.de
2020-09-16 16:52:33 +02:00
Thomas Gleixner
55e0391572 x86/irq: Consolidate DMAR irq allocation
None of the DMAR specific fields are required.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200826112332.163462706@linutronix.de
2020-09-16 16:52:33 +02:00
Thomas Gleixner
33a65ba470 x86_ioapic_Consolidate_IOAPIC_allocation
Move the IOAPIC specific fields into their own struct and reuse the common
devid. Get rid of the #ifdeffery as it does not matter at all whether the
alloc info is a couple of bytes longer or not.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20200826112332.054367732@linutronix.de
2020-09-16 16:52:32 +02:00
Thomas Gleixner
2bf1e7bced x86/msi: Consolidate HPET allocation
None of the magic HPET fields are required in any way.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20200826112331.943993771@linutronix.de
2020-09-16 16:52:31 +02:00
Thomas Gleixner
874d9b3a95 x86/irq: Prepare consolidation of irq_alloc_info
struct irq_alloc_info is a horrible zoo of unnamed structs in a union. Many
of the struct fields can be generic and don't have to be type specific like
hpet_id, ioapic_id...

Provide a generic set of members to prepare for the consolidation. The goal
is to make irq_alloc_info have the same basic member as the generic
msi_alloc_info so generic MSI domain ops can be reused and yet more mess
can be avoided when (non-PCI) device MSI support comes along.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200826112331.849577844@linutronix.de
2020-09-16 16:52:30 +02:00
Thomas Gleixner
6b6256e616 iommu/irq_remapping: Consolidate irq domain lookup
Now that the iommu implementations handle the X86_*_GET_PARENT_DOMAIN
types, consolidate the two getter functions.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20200826112331.741909337@linutronix.de
2020-09-16 16:52:30 +02:00
Thomas Gleixner
b4c364da32 x86/irq: Add allocation type for parent domain retrieval
irq_remapping_ir_irq_domain() is used to retrieve the remapping parent
domain for an allocation type. irq_remapping_irq_domain() is for retrieving
the actual device domain for allocating interrupts for a device.

The two functions are similar and can be unified by using explicit modes
for parent irq domain retrieval.

Add X86_IRQ_ALLOC_TYPE_IOAPIC/HPET_GET_PARENT and use it in the iommu
implementations. Drop the parent domain retrieval for PCI_MSI/X as that is
unused.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20200826112331.436350257@linutronix.de
2020-09-16 16:52:29 +02:00
Thomas Gleixner
801b5e4c4e x86_irq_Rename_X86_IRQ_ALLOC_TYPE_MSI_to_reflect_PCI_dependency
No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20200826112331.343103175@linutronix.de
2020-09-16 16:52:29 +02:00
Thomas Gleixner
9d55f02ad4 x86/msi: Remove pointless vcpu_affinity callback
Setting the irq_set_vcpu_affinity() callback to
irq_chip_set_vcpu_affinity_parent() is a pointless exercise because the
function which utilizes it searchs the domain hierarchy to find a parent
domain which has such a callback.

Remove the useless indirection.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200826112331.250130127@linutronix.de
2020-09-16 16:52:29 +02:00
Thomas Gleixner
b0a19555ef x86/msi: Move compose message callback where it belongs
Composing the MSI message at the MSI chip level is wrong because the
underlying parent domain is the one which knows how the message should be
composed for the direct vector delivery or the interrupt remapping table
entry.

The interrupt remapping aware PCI/MSI chip does that already. Make the
direct delivery chip do the same and move the composition of the direct
delivery MSI message to the vector domain irq chip.

This prepares for the upcoming device MSI support to avoid having
architecture specific knowledge in the device MSI domain irq chips.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200826112331.157603198@linutronix.de
2020-09-16 16:52:28 +02:00
Thomas Gleixner
13b90cadfc genirq/chip: Use the first chip in irq_chip_compose_msi_msg()
The documentation of irq_chip_compose_msi_msg() claims that with
hierarchical irq domains the first chip in the hierarchy which has an
irq_compose_msi_msg() callback is chosen. But the code just keeps
iterating after it finds a chip with a compose callback.

The x86 HPET MSI implementation relies on that behaviour, but that does not
make it more correct.

The message should always be composed at the domain which manages the
underlying resource (e.g. APIC or remap table) because that domain knows
about the required layout of the message.

On X86 the following hierarchies exist:

1)   vector -------- PCI/MSI
2)   vector -- IR -- PCI/MSI

The vector domain has a different message format than the IR (remapping)
domain. So obviously the PCI/MSI domain can't compose the message without
having knowledge about the parent domain, which is exactly the opposite of
what hierarchical domains want to achieve.

X86 actually has two different PCI/MSI chips where #1 has a compose
callback and #2 does not. #2 delegates the composition to the remap domain
where it belongs, but #1 does it at the PCI/MSI level.

For the upcoming device MSI support it's necessary to change this and just
let the first domain which can compose the message take care of it. That
way the top level chip does not have to worry about it and the device MSI
code does not need special knowledge about topologies. It just sets the
compose callback to NULL and lets the hierarchy pick the first chip which
has one.

Due to that the attempt to move the compose callback from the direct
delivery PCI/MSI domain to the vector domain made the system fail to boot
with interrupt remapping enabled because in the remapping case
irq_chip_compose_msi_msg() keeps iterating and choses the compose callback
of the vector domain which obviously creates the wrong format for the remap
table.

Break out of the loop when the first irq chip with a compose callback is
found and fixup the HPET code temporarily. That workaround will be removed
once the direct delivery compose callback is moved to the place where it
belongs in the vector domain.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <maz@kernel.org>                                                                                                                                                                                                                                     Link: https://lore.kernel.org/r/20200826112331.047917603@linutronix.de
2020-09-16 16:52:28 +02:00
Thomas Gleixner
ccbecea146 x86/init: Remove unused init ops
Some past platform removal forgot to get rid of this unused ballast.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200826112330.806095671@linutronix.de
2020-09-16 16:52:28 +02:00
Linus Torvalds
84b1349972 ARM:
- Multiple stolen time fixes, with a new capability to match x86
 - Fix for hugetlbfs mappings when PUD and PMD are the same level
 - Fix for hugetlbfs mappings when PTE mappings are enforced
   (dirty logging, for example)
 - Fix tracing output of 64bit values
 
 x86:
 - nSVM state restore fixes
 - Async page fault fixes
 - Lots of small fixes everywhere
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "A bit on the bigger side, mostly due to me being on vacation, then
  busy, then on parental leave, but there's nothing worrisome.

  ARM:
   - Multiple stolen time fixes, with a new capability to match x86
   - Fix for hugetlbfs mappings when PUD and PMD are the same level
   - Fix for hugetlbfs mappings when PTE mappings are enforced (dirty
     logging, for example)
   - Fix tracing output of 64bit values

  x86:
   - nSVM state restore fixes
   - Async page fault fixes
   - Lots of small fixes everywhere"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (25 commits)
  KVM: emulator: more strict rsm checks.
  KVM: nSVM: more strict SMM checks when returning to nested guest
  SVM: nSVM: setup nested msr permission bitmap on nested state load
  SVM: nSVM: correctly restore GIF on vmexit from nesting after migration
  x86/kvm: don't forget to ACK async PF IRQ
  x86/kvm: properly use DEFINE_IDTENTRY_SYSVEC() macro
  KVM: VMX: Don't freeze guest when event delivery causes an APIC-access exit
  KVM: SVM: avoid emulation with stale next_rip
  KVM: x86: always allow writing '0' to MSR_KVM_ASYNC_PF_EN
  KVM: SVM: Periodically schedule when unregistering regions on destroy
  KVM: MIPS: Change the definition of kvm type
  kvm x86/mmu: use KVM_REQ_MMU_SYNC to sync when needed
  KVM: nVMX: Fix the update value of nested load IA32_PERF_GLOBAL_CTRL control
  KVM: fix memory leak in kvm_io_bus_unregister_dev()
  KVM: Check the allocation of pv cpu mask
  KVM: nVMX: Update VMCS02 when L2 PAE PDPTE updates detected
  KVM: arm64: Update page shift if stage 2 block mapping not supported
  KVM: arm64: Fix address truncation in traces
  KVM: arm64: Do not try to map PUDs when they are folded into PMD
  arm64/x86: KVM: Introduce steal-time cap
  ...
2020-09-13 08:34:47 -07:00
Maxim Levitsky
37f66bbef0 KVM: emulator: more strict rsm checks.
Don't ignore return values in rsm_load_state_64/32 to avoid
loading invalid state from SMM state area if it was tampered with
by the guest.

This is primarly intended to avoid letting guest set bits in EFER
(like EFER.SVME when nesting is disabled) by manipulating SMM save area.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200827171145.374620-8-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-12 12:22:55 -04:00
Maxim Levitsky
3ebb5d2617 KVM: nSVM: more strict SMM checks when returning to nested guest
* check that guest is 64 bit guest, otherwise the SVM related fields
  in the smm state area are not defined

* If the SMM area indicates that SMM interrupted a running guest,
  check that EFER.SVME which is also saved in this area is set, otherwise
  the guest might have tampered with SMM save area, and so indicate
  emulation failure which should triple fault the guest.

* Check that that guest CPUID supports SVM (due to the same issue as above)

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200827162720.278690-4-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-12 12:21:43 -04:00
Maxim Levitsky
772b81bb2f SVM: nSVM: setup nested msr permission bitmap on nested state load
This code was missing and was forcing the L2 run with L1's msr
permission bitmap

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200827162720.278690-3-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-12 12:20:53 -04:00
Maxim Levitsky
9883764ad0 SVM: nSVM: correctly restore GIF on vmexit from nesting after migration
Currently code in svm_set_nested_state copies the current vmcb control
area to L1 control area (hsave->control), under assumption that
it mostly reflects the defaults that kvm choose, and later qemu
overrides  these defaults with L2 state using standard KVM interfaces,
like KVM_SET_REGS.

However nested GIF (which is AMD specific thing) is by default is true,
and it is copied to hsave area as such.

This alone is not a big deal since on VMexit, GIF is always set to false,
regardless of what it was on VM entry.  However in nested_svm_vmexit we
were first were setting GIF to false, but then we overwrite the control
fields with value from the hsave area.  (including the nested GIF field
itself if GIF virtualization is enabled).

Now on normal vm entry this is not a problem, since GIF is usually false
prior to normal vm entry, and this is the value that copied to hsave,
and then restored, but this is not always the case when the nested state
is loaded as explained above.

To fix this issue, move svm_set_gif after we restore the L1 control
state in nested_svm_vmexit, so that even with wrong GIF in the
saved L1 control area, we still clear GIF as the spec says.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200827162720.278690-2-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-12 12:19:06 -04:00
Vitaly Kuznetsov
cc17b22559 x86/kvm: don't forget to ACK async PF IRQ
Merge commit 26d05b368a ("Merge branch 'kvm-async-pf-int' into HEAD")
tried to adapt the new interrupt based async PF mechanism to the newly
introduced IDTENTRY magic but unfortunately it missed the fact that
DEFINE_IDTENTRY_SYSVEC() doesn't call ack_APIC_irq() on its own and
all DEFINE_IDTENTRY_SYSVEC() users have to call it manually.

As the result all multi-CPU KVM guest hang on boot when
KVM_FEATURE_ASYNC_PF_INT is present. The breakage went unnoticed because no
KVM userspace (e.g. QEMU) currently set it (and thus async PF mechanism
is currently disabled) but we're about to change that.

Fixes: 26d05b368a ("Merge branch 'kvm-async-pf-int' into HEAD")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200908135350.355053-3-vkuznets@redhat.com>
Tested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-12 02:22:21 -04:00
Vitaly Kuznetsov
244081f907 x86/kvm: properly use DEFINE_IDTENTRY_SYSVEC() macro
DEFINE_IDTENTRY_SYSVEC() already contains irqentry_enter()/
irqentry_exit().

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200908135350.355053-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-12 02:22:07 -04:00
Wanpeng Li
99b82a1437 KVM: VMX: Don't freeze guest when event delivery causes an APIC-access exit
According to SDM 27.2.4, Event delivery causes an APIC-access VM exit.
Don't report internal error and freeze guest when event delivery causes
an APIC-access exit, it is handleable and the event will be re-injected
during the next vmentry.

Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1597827327-25055-2-git-send-email-wanpengli@tencent.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-12 02:21:17 -04:00
Wanpeng Li
e42c68281b KVM: SVM: avoid emulation with stale next_rip
svm->next_rip is reset in svm_vcpu_run() only after calling
svm_exit_handlers_fastpath(), which will cause SVM's
skip_emulated_instruction() to write a stale RIP.

We can move svm_exit_handlers_fastpath towards the end of
svm_vcpu_run().  To align VMX with SVM, keep svm_complete_interrupts()
close as well.

Suggested-by: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Paul K. <kronenpj@kronenpj.dyndns.org>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
[Also move vmcb_mark_all_clean before any possible write to the VMCB.
 - Paolo]
2020-09-12 02:19:23 -04:00
Vitaly Kuznetsov
d831de1772 KVM: x86: always allow writing '0' to MSR_KVM_ASYNC_PF_EN
Even without in-kernel LAPIC we should allow writing '0' to
MSR_KVM_ASYNC_PF_EN as we're not enabling the mechanism. In
particular, QEMU with 'kernel-irqchip=off' fails to start
a guest with

qemu-system-x86_64: error: failed to set MSR 0x4b564d02 to 0x0

Fixes: 9d3c447c72 ("KVM: X86: Fix async pf caused null-ptr-deref")
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200911093147.484565-1-vkuznets@redhat.com>
[Actually commit the version proposed by Sean Christopherson. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-11 13:26:47 -04:00
David Rientjes
7be74942f1 KVM: SVM: Periodically schedule when unregistering regions on destroy
There may be many encrypted regions that need to be unregistered when a
SEV VM is destroyed.  This can lead to soft lockups.  For example, on a
host running 4.15:

watchdog: BUG: soft lockup - CPU#206 stuck for 11s! [t_virtual_machi:194348]
CPU: 206 PID: 194348 Comm: t_virtual_machi
RIP: 0010:free_unref_page_list+0x105/0x170
...
Call Trace:
 [<0>] release_pages+0x159/0x3d0
 [<0>] sev_unpin_memory+0x2c/0x50 [kvm_amd]
 [<0>] __unregister_enc_region_locked+0x2f/0x70 [kvm_amd]
 [<0>] svm_vm_destroy+0xa9/0x200 [kvm_amd]
 [<0>] kvm_arch_destroy_vm+0x47/0x200
 [<0>] kvm_put_kvm+0x1a8/0x2f0
 [<0>] kvm_vm_release+0x25/0x30
 [<0>] do_exit+0x335/0xc10
 [<0>] do_group_exit+0x3f/0xa0
 [<0>] get_signal+0x1bc/0x670
 [<0>] do_signal+0x31/0x130

Although the CLFLUSH is no longer issued on every encrypted region to be
unregistered, there are no other changes that can prevent soft lockups for
very large SEV VMs in the latest kernel.

Periodically schedule if necessary.  This still holds kvm->lock across the
resched, but since this only happens when the VM is destroyed this is
assumed to be acceptable.

Signed-off-by: David Rientjes <rientjes@google.com>
Message-Id: <alpine.DEB.2.23.453.2008251255240.2987727@chino.kir.corp.google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-11 13:24:15 -04:00
Lai Jiangshan
f6f6195b88 kvm x86/mmu: use KVM_REQ_MMU_SYNC to sync when needed
When kvm_mmu_get_page() gets a page with unsynced children, the spt
pagetable is unsynchronized with the guest pagetable. But the
guest might not issue a "flush" operation on it when the pagetable
entry is changed from zero or other cases. The hypervisor has the
responsibility to synchronize the pagetables.

KVM behaved as above for many years, But commit 8c8560b833
("KVM: x86/mmu: Use KVM_REQ_TLB_FLUSH_CURRENT for MMU specific flushes")
inadvertently included a line of code to change it without giving any
reason in the changelog. It is clear that the commit's intention was to
change KVM_REQ_TLB_FLUSH -> KVM_REQ_TLB_FLUSH_CURRENT, so we don't
needlessly flush other contexts; however, one of the hunks changed
a nearby KVM_REQ_MMU_SYNC instead.  This patch changes it back.

Link: https://lore.kernel.org/lkml/20200320212833.3507-26-sean.j.christopherson@intel.com/
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20200902135421.31158-1-jiangshanlai@gmail.com>
fixes: 8c8560b833 ("KVM: x86/mmu: Use KVM_REQ_TLB_FLUSH_CURRENT for MMU specific flushes")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-11 13:16:55 -04:00
Chenyi Qiang
c6b177a3be KVM: nVMX: Fix the update value of nested load IA32_PERF_GLOBAL_CTRL control
A minor fix for the update of VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL field
in exit_ctls_high.

Fixes: 03a8871add ("KVM: nVMX: Expose load IA32_PERF_GLOBAL_CTRL
VM-{Entry,Exit} control")
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20200828085622.8365-5-chenyi.qiang@intel.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-11 13:15:12 -04:00
Haiwei Li
0f99022210 KVM: Check the allocation of pv cpu mask
check the allocation of per-cpu __pv_cpu_mask. Initialize ops only when
successful.

Signed-off-by: Haiwei Li <lihaiwei@tencent.com>
Message-Id: <d59f05df-e6d3-3d31-a036-cc25a2b2f33f@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-11 13:15:10 -04:00
Peter Shier
43fea4e425 KVM: nVMX: Update VMCS02 when L2 PAE PDPTE updates detected
When L2 uses PAE, L0 intercepts of L2 writes to CR0/CR3/CR4 call
load_pdptrs to read the possibly updated PDPTEs from the guest
physical address referenced by CR3.  It loads them into
vcpu->arch.walk_mmu->pdptrs and sets VCPU_EXREG_PDPTR in
vcpu->arch.regs_dirty.

At the subsequent assumed reentry into L2, the mmu will call
vmx_load_mmu_pgd which calls ept_load_pdptrs. ept_load_pdptrs sees
VCPU_EXREG_PDPTR set in vcpu->arch.regs_dirty and loads
VMCS02.GUEST_PDPTRn from vcpu->arch.walk_mmu->pdptrs[]. This all works
if the L2 CRn write intercept always resumes L2.

The resume path calls vmx_check_nested_events which checks for
exceptions, MTF, and expired VMX preemption timers. If
vmx_check_nested_events finds any of these conditions pending it will
reflect the corresponding exit into L1. Live migration at this point
would also cause a missed immediate reentry into L2.

After L1 exits, vmx_vcpu_run calls vmx_register_cache_reset which
clears VCPU_EXREG_PDPTR in vcpu->arch.regs_dirty.  When L2 next
resumes, ept_load_pdptrs finds VCPU_EXREG_PDPTR clear in
vcpu->arch.regs_dirty and does not load VMCS02.GUEST_PDPTRn from
vcpu->arch.walk_mmu->pdptrs[]. prepare_vmcs02 will then load
VMCS02.GUEST_PDPTRn from vmcs12->pdptr0/1/2/3 which contain the stale
values stored at last L2 exit. A repro of this bug showed L2 entering
triple fault immediately due to the bad VMCS02.GUEST_PDPTRn values.

When L2 is in PAE paging mode add a call to ept_load_pdptrs before
leaving L2. This will update VMCS02.GUEST_PDPTRn if they are dirty in
vcpu->arch.walk_mmu->pdptrs[].

Tested:
kvm-unit-tests with new directed test: vmx_mtf_pdpte_test.
Verified that test fails without the fix.

Also ran Google internal VMM with an Ubuntu 16.04 4.4.0-83 guest running a
custom hypervisor with a 32-bit Windows XP L2 guest using PAE. Prior to fix
would repro readily. Ran 14 simultaneous L2s for 140 iterations with no
failures.

Signed-off-by: Peter Shier <pshier@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Message-Id: <20200820230545.2411347-1-pshier@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-11 13:15:09 -04:00
Paolo Bonzini
1b67fd086d KVM/arm64 fixes for Linux 5.9, take #1
- Multiple stolen time fixes, with a new capability to match x86
 - Fix for hugetlbfs mappings when PUD and PMD are the same level
 - Fix for hugetlbfs mappings when PTE mappings are enforced
   (dirty logging, for example)
 - Fix tracing output of 64bit values
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Merge tag 'kvmarm-fixes-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for Linux 5.9, take #1

- Multiple stolen time fixes, with a new capability to match x86
- Fix for hugetlbfs mappings when PUD and PMD are the same level
- Fix for hugetlbfs mappings when PTE mappings are enforced
  (dirty logging, for example)
- Fix tracing output of 64bit values
2020-09-11 13:12:11 -04:00
Thomas Gleixner
4facb95b7a x86/entry: Unbreak 32bit fast syscall
Andy reported that the syscall treacing for 32bit fast syscall fails:

# ./tools/testing/selftests/x86/ptrace_syscall_32
...
[RUN] SYSEMU
[FAIL] Initial args are wrong (nr=224, args=10 11 12 13 14 4289172732)
...
[RUN] SYSCALL
[FAIL] Initial args are wrong (nr=29, args=0 0 0 0 0 4289172732)
 
The eason is that the conversion to generic entry code moved the retrieval
of the sixth argument (EBP) after the point where the syscall entry work
runs, i.e. ptrace, seccomp, audit...

Unbreak it by providing a split up version of syscall_enter_from_user_mode().

- syscall_enter_from_user_mode_prepare() establishes state and enables
  interrupts

- syscall_enter_from_user_mode_work() runs the entry work

Replace the call to syscall_enter_from_user_mode() in the 32bit fast
syscall C-entry with the split functions and stick the EBP retrieval
between them.

Fixes: 27d6b4d14f ("x86/entry: Use generic syscall entry function")
Reported-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/87k0xdjbtt.fsf@nanos.tec.linutronix.de
2020-09-04 15:50:14 +02:00
Andy Lutomirski
d5c678aed5 x86/debug: Allow a single level of #DB recursion
Trying to clear DR7 around a #DB from usermode malfunctions if the tasks
schedules when delivering SIGTRAP.

Rather than trying to define a special no-recursion region, just allow a
single level of recursion.  The same mechanism is used for NMI, and it
hasn't caused any problems yet.

Fixes: 9f58fdde95 ("x86/db: Split out dr6/7 handling")
Reported-by: Kyle Huey <me@kylehuey.com>
Debugged-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/8b9bd05f187231df008d48cf818a6a311cbd5c98.1597882384.git.luto@kernel.org
Link: https://lore.kernel.org/r/20200902133200.726584153@infradead.org
2020-09-04 15:09:29 +02:00
Peter Zijlstra
662a022189 x86/entry: Fix AC assertion
The WARN added in commit 3c73b81a91 ("x86/entry, selftests: Further
improve user entry sanity checks") unconditionally triggers on a IVB
machine because it does not support SMAP.

For !SMAP hardware the CLAC/STAC instructions are patched out and thus if
userspace sets AC, it is still have set after entry.

Fixes: 3c73b81a91 ("x86/entry, selftests: Further improve user entry sanity checks")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200902133200.666781610@infradead.org
2020-09-04 15:09:29 +02:00
Vamshi K Sthambamkadi
2356bb4b82 tracing/kprobes, x86/ptrace: Fix regs argument order for i386
On i386, the order of parameters passed on regs is eax,edx,and ecx
(as per regparm(3) calling conventions).

Change the mapping in regs_get_kernel_argument(), so that arg1=ax
arg2=dx, and arg3=cx.

Running the selftests testcase kprobes_args_use.tc shows the result
as passed.

Fixes: 3c88ee194c ("x86: ptrace: Add function argument access API")
Signed-off-by: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200828113242.GA1424@cosmos
2020-09-04 14:40:42 +02:00
Huang Ying
ccae0f36d5 x86, fakenuma: Fix invalid starting node ID
Commit:

  cc9aec03e5 ("x86/numa_emulation: Introduce uniform split capability")

uses "-1" as the starting node ID, which causes the strange kernel log as
follows, when "numa=fake=32G" is added to the kernel command line:

    Faking node -1 at [mem 0x0000000000000000-0x0000000893ffffff] (35136MB)
    Faking node 0 at [mem 0x0000001840000000-0x000000203fffffff] (32768MB)
    Faking node 1 at [mem 0x0000000894000000-0x000000183fffffff] (64192MB)
    Faking node 2 at [mem 0x0000002040000000-0x000000283fffffff] (32768MB)
    Faking node 3 at [mem 0x0000002840000000-0x000000303fffffff] (32768MB)

And finally the kernel crashes:

    BUG: Bad page state in process swapper  pfn:00011
    page:(____ptrval____) refcount:0 mapcount:1 mapping:(____ptrval____) index:0x55cd7e44b270 pfn:0x11
    failed to read mapping contents, not a valid kernel address?
    flags: 0x5(locked|uptodate)
    raw: 0000000000000005 000055cd7e44af30 000055cd7e44af50 0000000100000006
    raw: 000055cd7e44b270 000055cd7e44b290 0000000000000000 000055cd7e44b510
    page dumped because: page still charged to cgroup
    page->mem_cgroup:000055cd7e44b510
    Modules linked in:
    CPU: 0 PID: 0 Comm: swapper Not tainted 5.9.0-rc2 #1
    Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019
    Call Trace:
     dump_stack+0x57/0x80
     bad_page.cold+0x63/0x94
     __free_pages_ok+0x33f/0x360
     memblock_free_all+0x127/0x195
     mem_init+0x23/0x1f5
     start_kernel+0x219/0x4f5
     secondary_startup_64+0xb6/0xc0

Fix this bug via using 0 as the starting node ID.  This restores the
original behavior before cc9aec03e5.

[ mingo: Massaged the changelog. ]

Fixes: cc9aec03e5 ("x86/numa_emulation: Introduce uniform split capability")
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200904061047.612950-1-ying.huang@intel.com
2020-09-04 08:56:13 +02:00
Joerg Roedel
4819e15f74 x86/mm/32: Bring back vmalloc faulting on x86_32
One can not simply remove vmalloc faulting on x86-32. Upstream

	commit: 7f0a002b5a ("x86/mm: remove vmalloc faulting")

removed it on x86 alltogether because previously the
arch_sync_kernel_mappings() interface was introduced. This interface
added synchronization of vmalloc/ioremap page-table updates to all
page-tables in the system at creation time and was thought to make
vmalloc faulting obsolete.

But that assumption was incredibly naive.

It turned out that there is a race window between the time the vmalloc
or ioremap code establishes a mapping and the time it synchronizes
this change to other page-tables in the system.

During this race window another CPU or thread can establish a vmalloc
mapping which uses the same intermediate page-table entries (e.g. PMD
or PUD) and does no synchronization in the end, because it found all
necessary mappings already present in the kernel reference page-table.

But when these intermediate page-table entries are not yet
synchronized, the other CPU or thread will continue with a vmalloc
address that is not yet mapped in the page-table it currently uses,
causing an unhandled page fault and oops like below:

	BUG: unable to handle page fault for address: fe80c000
	#PF: supervisor write access in kernel mode
	#PF: error_code(0x0002) - not-present page
	*pde = 33183067 *pte = a8648163
	Oops: 0002 [#1] SMP
	CPU: 1 PID: 13514 Comm: cve-2017-17053 Tainted: G
	...
	Call Trace:
	 ldt_dup_context+0x66/0x80
	 dup_mm+0x2b3/0x480
	 copy_process+0x133b/0x15c0
	 _do_fork+0x94/0x3e0
	 __ia32_sys_clone+0x67/0x80
	 __do_fast_syscall_32+0x3f/0x70
	 do_fast_syscall_32+0x29/0x60
	 do_SYSENTER_32+0x15/0x20
	 entry_SYSENTER_32+0x9f/0xf2
	EIP: 0xb7eef549

So the arch_sync_kernel_mappings() interface is racy, but removing it
would mean to re-introduce the vmalloc_sync_all() interface, which is
even more awful. Keep arch_sync_kernel_mappings() in place and catch
the race condition in the page-fault handler instead.

Do a partial revert of above commit to get vmalloc faulting on x86-32
back in place.

Fixes: 7f0a002b5a ("x86/mm: remove vmalloc faulting")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200902155904.17544-1-joro@8bytes.org
2020-09-03 11:23:35 +02:00
Arvind Sankar
aef0148f36 x86/cmdline: Disable jump tables for cmdline.c
When CONFIG_RETPOLINE is disabled, Clang uses a jump table for the
switch statement in cmdline_find_option (jump tables are disabled when
CONFIG_RETPOLINE is enabled). This function is called very early in boot
from sme_enable() if CONFIG_AMD_MEM_ENCRYPT is enabled. At this time,
the kernel is still executing out of the identity mapping, but the jump
table will contain virtual addresses.

Fix this by disabling jump tables for cmdline.c when AMD_MEM_ENCRYPT is
enabled.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200903023056.3914690-1-nivedita@alum.mit.edu
2020-09-03 10:59:16 +02:00
Linus Torvalds
dcc5c6f013 Three interrupt related fixes for X86:
- Move disabling of the local APIC after invoking fixup_irqs() to ensure
    that interrupts which are incoming are noted in the IRR and not ignored.
 
  - Unbreak affinity setting. The rework of the entry code reused the
    regular exception entry code for device interrupts. The vector number is
    pushed into the errorcode slot on the stack which is then lifted into an
    argument and set to -1 because that's regs->orig_ax which is used in
    quite some places to check whether the entry came from a syscall. But it
    was overlooked that orig_ax is used in the affinity cleanup code to
    validate whether the interrupt has arrived on the new target. It turned
    out that this vector check is pointless because interrupts are never
    moved from one vector to another on the same CPU. That check is a
    historical leftover from the time where x86 supported multi-CPU
    affinities, but not longer needed with the now strict single CPU
    affinity. Famous last words ...
 
  - Add a missing check for an empty cpumask into the matrix allocator. The
    affinity change added a warning to catch the case where an interrupt is
    moved on the same CPU to a different vector. This triggers because a
    condition with an empty cpumask returns an assignment from the allocator
    as the allocator uses for_each_cpu() without checking the cpumask for
    being empty. The historical inconsistent for_each_cpu() behaviour of
    ignoring the cpumask and unconditionally claiming that CPU0 is in the
    mask striked again. Sigh.
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Merge tag 'x86-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "Three interrupt related fixes for X86:

   - Move disabling of the local APIC after invoking fixup_irqs() to
     ensure that interrupts which are incoming are noted in the IRR and
     not ignored.

   - Unbreak affinity setting.

     The rework of the entry code reused the regular exception entry
     code for device interrupts. The vector number is pushed into the
     errorcode slot on the stack which is then lifted into an argument
     and set to -1 because that's regs->orig_ax which is used in quite
     some places to check whether the entry came from a syscall.

     But it was overlooked that orig_ax is used in the affinity cleanup
     code to validate whether the interrupt has arrived on the new
     target. It turned out that this vector check is pointless because
     interrupts are never moved from one vector to another on the same
     CPU. That check is a historical leftover from the time where x86
     supported multi-CPU affinities, but not longer needed with the now
     strict single CPU affinity. Famous last words ...

   - Add a missing check for an empty cpumask into the matrix allocator.

     The affinity change added a warning to catch the case where an
     interrupt is moved on the same CPU to a different vector. This
     triggers because a condition with an empty cpumask returns an
     assignment from the allocator as the allocator uses for_each_cpu()
     without checking the cpumask for being empty. The historical
     inconsistent for_each_cpu() behaviour of ignoring the cpumask and
     unconditionally claiming that CPU0 is in the mask struck again.
     Sigh.

  plus a new entry into the MAINTAINER file for the HPE/UV platform"

* tag 'x86-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/matrix: Deal with the sillyness of for_each_cpu() on UP
  x86/irq: Unbreak interrupt affinity setting
  x86/hotplug: Silence APIC only after all interrupts are migrated
  MAINTAINERS: Add entry for HPE Superdome Flex (UV) maintainers
2020-08-30 12:01:23 -07:00
Linus Torvalds
b69bea8a65 A set of fixes for lockdep, tracing and RCU:
- Prevent recursion by using raw_cpu_* operations
 
   - Fixup the interrupt state in the cpu idle code to be consistent
 
   - Push rcu_idle_enter/exit() invocations deeper into the idle path so
     that the lock operations are inside the RCU watching sections
 
   - Move trace_cpu_idle() into generic code so it's called before RCU goes
     idle.
 
   - Handle raw_local_irq* vs. local_irq* operations correctly
 
   - Move the tracepoints out from under the lockdep recursion handling
     which turned out to be fragile and inconsistent.
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Merge tag 'locking-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fixes from Thomas Gleixner:
 "A set of fixes for lockdep, tracing and RCU:

   - Prevent recursion by using raw_cpu_* operations

   - Fixup the interrupt state in the cpu idle code to be consistent

   - Push rcu_idle_enter/exit() invocations deeper into the idle path so
     that the lock operations are inside the RCU watching sections

   - Move trace_cpu_idle() into generic code so it's called before RCU
     goes idle.

   - Handle raw_local_irq* vs. local_irq* operations correctly

   - Move the tracepoints out from under the lockdep recursion handling
     which turned out to be fragile and inconsistent"

* tag 'locking-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep,trace: Expose tracepoints
  lockdep: Only trace IRQ edges
  mips: Implement arch_irqs_disabled()
  arm64: Implement arch_irqs_disabled()
  nds32: Implement arch_irqs_disabled()
  locking/lockdep: Cleanup
  x86/entry: Remove unused THUNKs
  cpuidle: Move trace_cpu_idle() into generic code
  cpuidle: Make CPUIDLE_FLAG_TLB_FLUSHED generic
  sched,idle,rcu: Push rcu_idle deeper into the idle path
  cpuidle: Fixup IRQ state
  lockdep: Use raw_cpu_*() for per-cpu variables
2020-08-30 11:43:50 -07:00
Thomas Gleixner
e027fffff7 x86/irq: Unbreak interrupt affinity setting
Several people reported that 5.8 broke the interrupt affinity setting
mechanism.

The consolidation of the entry code reused the regular exception entry code
for device interrupts and changed the way how the vector number is conveyed
from ptregs->orig_ax to a function argument.

The low level entry uses the hardware error code slot to push the vector
number onto the stack which is retrieved from there into a function
argument and the slot on stack is set to -1.

The reason for setting it to -1 is that the error code slot is at the
position where pt_regs::orig_ax is. A positive value in pt_regs::orig_ax
indicates that the entry came via a syscall. If it's not set to a negative
value then a signal delivery on return to userspace would try to restart a
syscall. But there are other places which rely on pt_regs::orig_ax being a
valid indicator for syscall entry.

But setting pt_regs::orig_ax to -1 has a nasty side effect vs. the
interrupt affinity setting mechanism, which was overlooked when this change
was made.

Moving interrupts on x86 happens in several steps. A new vector on a
different CPU is allocated and the relevant interrupt source is
reprogrammed to that. But that's racy and there might be an interrupt
already in flight to the old vector. So the old vector is preserved until
the first interrupt arrives on the new vector and the new target CPU. Once
that happens the old vector is cleaned up, but this cleanup still depends
on the vector number being stored in pt_regs::orig_ax, which is now -1.

That -1 makes the check for cleanup: pt_regs::orig_ax == new_vector
always false. As a consequence the interrupt is moved once, but then it
cannot be moved anymore because the cleanup of the old vector never
happens.

There would be several ways to convey the vector information to that place
in the guts of the interrupt handling, but on deeper inspection it turned
out that this check is pointless and a leftover from the old affinity model
of X86 which supported multi-CPU affinities. Under this model it was
possible that an interrupt had an old and a new vector on the same CPU, so
the vector match was required.

Under the new model the effective affinity of an interrupt is always a
single CPU from the requested affinity mask. If the affinity mask changes
then either the interrupt stays on the CPU and on the same vector when that
CPU is still in the new affinity mask or it is moved to a different CPU, but
it is never moved to a different vector on the same CPU.

Ergo the cleanup check for the matching vector number is not required and
can be removed which makes the dependency on pt_regs:orig_ax go away.

The remaining check for new_cpu == smp_processsor_id() is completely
sufficient. If it matches then the interrupt was successfully migrated and
the cleanup can proceed.

For paranoia sake add a warning into the vector assignment code to
validate that the assumption of never moving to a different vector on
the same CPU holds.

Fixes: 633260fa14 ("x86/irq: Convey vector as argument and not in ptregs")
Reported-by: Alex bykov <alex.bykov@scylladb.com>
Reported-by: Avi Kivity <avi@scylladb.com>
Reported-by: Alexander Graf <graf@amazon.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Graf <graf@amazon.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87wo1ltaxz.fsf@nanos.tec.linutronix.de
2020-08-27 09:29:23 +02:00
Ashok Raj
52d6b926aa x86/hotplug: Silence APIC only after all interrupts are migrated
There is a race when taking a CPU offline. Current code looks like this:

native_cpu_disable()
{
	...
	apic_soft_disable();
	/*
	 * Any existing set bits for pending interrupt to
	 * this CPU are preserved and will be sent via IPI
	 * to another CPU by fixup_irqs().
	 */
	cpu_disable_common();
	{
		....
		/*
		 * Race window happens here. Once local APIC has been
		 * disabled any new interrupts from the device to
		 * the old CPU are lost
		 */
		fixup_irqs(); // Too late to capture anything in IRR.
		...
	}
}

The fix is to disable the APIC *after* cpu_disable_common().

Testing was done with a USB NIC that provided a source of frequent
interrupts. A script migrated interrupts to a specific CPU and
then took that CPU offline.

Fixes: 60dcaad573 ("x86/hotplug: Silence APIC and NMI when CPU is dead")
Reported-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Tested-by: Evan Green <evgreen@chromium.org>
Reviewed-by: Evan Green <evgreen@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/875zdarr4h.fsf@nanos.tec.linutronix.de/
Link: https://lore.kernel.org/r/1598501530-45821-1-git-send-email-ashok.raj@intel.com
2020-08-27 09:29:23 +02:00
Peter Zijlstra
7da93f3793 x86/entry: Remove unused THUNKs
Unused remnants

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200821085348.487040689@infradead.org
2020-08-26 12:41:54 +02:00
Peter Zijlstra
9864f5b594 cpuidle: Move trace_cpu_idle() into generic code
Remove trace_cpu_idle() from the arch_cpu_idle() implementations and
put it in the generic code, right before disabling RCU. Gets rid of
more trace_*_rcuidle() users.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200821085348.428433395@infradead.org
2020-08-26 12:41:54 +02:00
Peter Zijlstra
bf9282dc26 cpuidle: Make CPUIDLE_FLAG_TLB_FLUSHED generic
This allows moving the leave_mm() call into generic code before
rcu_idle_enter(). Gets rid of more trace_*_rcuidle() users.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200821085348.369441600@infradead.org
2020-08-26 12:41:53 +02:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Linus Torvalds
550c2129d9 A single fix for x86 which removes the RDPID usage from the paranoid entry
path and unconditionally uses LSL to retrieve the CPU number. RDPID depends
 on MSR_TSX_AUX.  KVM has an optmization to avoid expensive MRS read/writes
 on VMENTER/EXIT. It caches the MSR values and restores them either when
 leaving the run loop, on preemption or when going out to user
 space. MSR_TSX_AUX is part of that lazy MSR set, so after writing the guest
 value and before the lazy restore any exception using the paranoid entry
 will read the guest value and use it as CPU number to retrieve the GSBASE
 value for the current CPU when FSGSBASE is enabled. As RDPID is only used
 in that particular entry path, there is no reason to burden VMENTER/EXIT
 with two extra MSR writes. Remove the RDPID optimization, which is not even
 backed by numbers from the paranoid entry path instead.
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Merge tag 'x86-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fix from Thomas Gleixner:
 "A single fix for x86 which removes the RDPID usage from the paranoid
  entry path and unconditionally uses LSL to retrieve the CPU number.

  RDPID depends on MSR_TSX_AUX. KVM has an optmization to avoid
  expensive MRS read/writes on VMENTER/EXIT. It caches the MSR values
  and restores them either when leaving the run loop, on preemption or
  when going out to user space. MSR_TSX_AUX is part of that lazy MSR
  set, so after writing the guest value and before the lazy restore any
  exception using the paranoid entry will read the guest value and use
  it as CPU number to retrieve the GSBASE value for the current CPU when
  FSGSBASE is enabled. As RDPID is only used in that particular entry
  path, there is no reason to burden VMENTER/EXIT with two extra MSR
  writes. Remove the RDPID optimization, which is not even backed by
  numbers from the paranoid entry path instead"

* tag 'x86-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/entry/64: Do not use RDPID in paranoid entry to accomodate KVM
2020-08-23 11:21:16 -07:00
Linus Torvalds
cea05c192b A single update for perf on x86 which ass support for the
broken down bandwith counters.
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Merge tag 'perf-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 perf fix from Thomas Gleixner:
 "A single update for perf on x86 which has support for the broken down
  bandwith counters"

* tag 'perf-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Add BW counters for GT, IA and IO breakdown
2020-08-23 11:15:14 -07:00