Commit Graph

2293 Commits

Author SHA1 Message Date
Linus Torvalds
bf953917be Various hardening fixes and cleanups for 5.16-rc1
Hi Linus,
 
 Please, pull the following hardening fixes and cleanups that I've
 been collecting during the last development cycle. All of them have
 been baking in linux-next.
 
 Fix -Wcast-function-type error:
 
 - firewire: Remove function callback casts (Oscar Carter)
 
 Fix application of sizeof operator:
 
 - firmware/psci: fix application of sizeof to pointer (jing yangyang)
 
 Replace open coded instances with size_t saturating arithmetic helpers:
 
 - assoc_array: Avoid open coded arithmetic in allocator arguments (Len Baker)
 - writeback: prefer struct_size over open coded arithmetic (Len Baker)
 - aio: Prefer struct_size over open coded arithmetic (Len Baker)
 - dmaengine: pxa_dma: Prefer struct_size over open coded arithmetic (Len Baker)
 
 Flexible array transformation:
 
 - KVM: PPC: Replace zero-length array with flexible array member (Len Baker)
 
 Use 2-factor argument multiplication form:
 
 - nouveau/svm: Use kvcalloc() instead of kvzalloc() (Gustavo A. R. Silva)
 - xfs: Use kvcalloc() instead of kvzalloc() (Gustavo A. R. Silva)
 
 Thanks
 --
 Gustavo
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Merge tag 'kspp-misc-fixes-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull hardening fixes and cleanups from Gustavo A. R. Silva:
 "Various hardening fixes and cleanups that I've been collecting during
  the last development cycle:

  Fix -Wcast-function-type error:

   - firewire: Remove function callback casts (Oscar Carter)

  Fix application of sizeof operator:

   - firmware/psci: fix application of sizeof to pointer (jing yangyang)

  Replace open coded instances with size_t saturating arithmetic
  helpers:

   - assoc_array: Avoid open coded arithmetic in allocator arguments
     (Len Baker)

   - writeback: prefer struct_size over open coded arithmetic (Len
     Baker)

   - aio: Prefer struct_size over open coded arithmetic (Len Baker)

   - dmaengine: pxa_dma: Prefer struct_size over open coded arithmetic
     (Len Baker)

  Flexible array transformation:

   - KVM: PPC: Replace zero-length array with flexible array member (Len
     Baker)

  Use 2-factor argument multiplication form:

   - nouveau/svm: Use kvcalloc() instead of kvzalloc() (Gustavo A. R.
     Silva)

   - xfs: Use kvcalloc() instead of kvzalloc() (Gustavo A. R. Silva)"

* tag 'kspp-misc-fixes-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  firewire: Remove function callback casts
  nouveau/svm: Use kvcalloc() instead of kvzalloc()
  firmware/psci: fix application of sizeof to pointer
  dmaengine: pxa_dma: Prefer struct_size over open coded arithmetic
  KVM: PPC: Replace zero-length array with flexible array member
  aio: Prefer struct_size over open coded arithmetic
  writeback: prefer struct_size over open coded arithmetic
  xfs: Use kvcalloc() instead of kvzalloc()
  assoc_array: Avoid open coded arithmetic in allocator arguments
2021-11-01 17:29:10 -07:00
Len Baker
5dfbbb668a KVM: PPC: Replace zero-length array with flexible array member
There is a regular need in the kernel to provide a way to declare having
a dynamically sized set of trailing elements in a structure. Kernel code
should always use "flexible array members" [1] for these cases. The
older style of one-element or zero-length arrays should no longer be
used[2].

Also, make use of the struct_size() helper in kzalloc().

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays

Signed-off-by: Len Baker <len.baker@gmx.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2021-10-20 18:30:42 -05:00
Michael Ellerman
cdeb5d7d89 KVM: PPC: Book3S HV: Make idle_kvm_start_guest() return 0 if it went to guest
We call idle_kvm_start_guest() from power7_offline() if the thread has
been requested to enter KVM. We pass it the SRR1 value that was returned
from power7_idle_insn() which tells us what sort of wakeup we're
processing.

Depending on the SRR1 value we pass in, the KVM code might enter the
guest, or it might return to us to do some host action if the wakeup
requires it.

If idle_kvm_start_guest() is able to handle the wakeup, and enter the
guest it is supposed to indicate that by returning a zero SRR1 value to
us.

That was the behaviour prior to commit 10d91611f4 ("powerpc/64s:
Reimplement book3s idle code in C"), however in that commit the
handling of SRR1 was reworked, and the zeroing behaviour was lost.

Returning from idle_kvm_start_guest() without zeroing the SRR1 value can
confuse the host offline code, causing the guest to crash and other
weirdness.

Fixes: 10d91611f4 ("powerpc/64s: Reimplement book3s idle code in C")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211015133929.832061-2-mpe@ellerman.id.au
2021-10-16 00:40:03 +11:00
Michael Ellerman
9b4416c509 KVM: PPC: Book3S HV: Fix stack handling in idle_kvm_start_guest()
In commit 10d91611f4 ("powerpc/64s: Reimplement book3s idle code in
C") kvm_start_guest() became idle_kvm_start_guest(). The old code
allocated a stack frame on the emergency stack, but didn't use the
frame to store anything, and also didn't store anything in its caller's
frame.

idle_kvm_start_guest() on the other hand is written more like a normal C
function, it creates a frame on entry, and also stores CR/LR into its
callers frame (per the ABI). The problem is that there is no caller
frame on the emergency stack.

The emergency stack for a given CPU is allocated with:

  paca_ptrs[i]->emergency_sp = alloc_stack(limit, i) + THREAD_SIZE;

So emergency_sp actually points to the first address above the emergency
stack allocation for a given CPU, we must not store above it without
first decrementing it to create a frame. This is different to the
regular kernel stack, paca->kstack, which is initialised to point at an
initial frame that is ready to use.

idle_kvm_start_guest() stores the backchain, CR and LR all of which
write outside the allocation for the emergency stack. It then creates a
stack frame and saves the non-volatile registers. Unfortunately the
frame it creates is not large enough to fit the non-volatiles, and so
the saving of the non-volatile registers also writes outside the
emergency stack allocation.

The end result is that we corrupt whatever is at 0-24 bytes, and 112-248
bytes above the emergency stack allocation.

In practice this has gone unnoticed because the memory immediately above
the emergency stack happens to be used for other stack allocations,
either another CPUs mc_emergency_sp or an IRQ stack. See the order of
calls to irqstack_early_init() and emergency_stack_init().

The low addresses of another stack are the top of that stack, and so are
only used if that stack is under extreme pressue, which essentially
never happens in practice - and if it did there's a high likelyhood we'd
crash due to that stack overflowing.

Still, we shouldn't be corrupting someone else's stack, and it is purely
luck that we aren't corrupting something else.

To fix it we save CR/LR into the caller's frame using the existing r1 on
entry, we then create a SWITCH_FRAME_SIZE frame (which has space for
pt_regs) on the emergency stack with the backchain pointing to the
existing stack, and then finally we switch to the new frame on the
emergency stack.

Fixes: 10d91611f4 ("powerpc/64s: Reimplement book3s idle code in C")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211015133929.832061-1-mpe@ellerman.id.au
2021-10-16 00:39:54 +11:00
Nicholas Piggin
267cdfa213 KVM: PPC: Book3S HV: Tolerate treclaim. in fake-suspend mode changing registers
POWER9 DD2.2 and 2.3 hardware implements a "fake-suspend" mode where
certain TM instructions executed in HV=0 mode cause softpatch interrupts
so the hypervisor can emulate them and prevent problematic processor
conditions. In this fake-suspend mode, the treclaim. instruction does
not modify registers.

Unfortunately the rfscv instruction executed by the guest do not
generate softpatch interrupts, which can cause the hypervisor to lose
track of the fake-suspend mode, and it can execute this treclaim. while
not in fake-suspend mode. This modifies GPRs and crashes the hypervisor.

It's not trivial to disable scv in the guest with HFSCR now, because
they assume a POWER9 has scv available. So this fix saves and restores
checkpointed registers across the treclaim.

Fixes: 7854f7545b ("KVM: PPC: Book3S: Rework TM save/restore code and make it C-callable")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210908101718.118522-2-npiggin@gmail.com
2021-09-13 22:34:12 +10:00
Linus Torvalds
192ad3c27a ARM:
- Page ownership tracking between host EL1 and EL2
 
 - Rely on userspace page tables to create large stage-2 mappings
 
 - Fix incompatibility between pKVM and kmemleak
 
 - Fix the PMU reset state, and improve the performance of the virtual PMU
 
 - Move over to the generic KVM entry code
 
 - Address PSCI reset issues w.r.t. save/restore
 
 - Preliminary rework for the upcoming pKVM fixed feature
 
 - A bunch of MM cleanups
 
 - a vGIC fix for timer spurious interrupts
 
 - Various cleanups
 
 s390:
 
 - enable interpretation of specification exceptions
 
 - fix a vcpu_idx vs vcpu_id mixup
 
 x86:
 
 - fast (lockless) page fault support for the new MMU
 
 - new MMU now the default
 
 - increased maximum allowed VCPU count
 
 - allow inhibit IRQs on KVM_RUN while debugging guests
 
 - let Hyper-V-enabled guests run with virtualized LAPIC as long as they
   do not enable the Hyper-V "AutoEOI" feature
 
 - fixes and optimizations for the toggling of AMD AVIC (virtualized LAPIC)
 
 - tuning for the case when two-dimensional paging (EPT/NPT) is disabled
 
 - bugfixes and cleanups, especially with respect to 1) vCPU reset and
   2) choosing a paging mode based on CR0/CR4/EFER
 
 - support for 5-level page table on AMD processors
 
 Generic:
 
 - MMU notifier invalidation callbacks do not take mmu_lock unless necessary
 
 - improved caching of LRU kvm_memory_slot
 
 - support for histogram statistics
 
 - add statistics for halt polling and remote TLB flush requests
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "ARM:
   - Page ownership tracking between host EL1 and EL2
   - Rely on userspace page tables to create large stage-2 mappings
   - Fix incompatibility between pKVM and kmemleak
   - Fix the PMU reset state, and improve the performance of the virtual
     PMU
   - Move over to the generic KVM entry code
   - Address PSCI reset issues w.r.t. save/restore
   - Preliminary rework for the upcoming pKVM fixed feature
   - A bunch of MM cleanups
   - a vGIC fix for timer spurious interrupts
   - Various cleanups

  s390:
   - enable interpretation of specification exceptions
   - fix a vcpu_idx vs vcpu_id mixup

  x86:
   - fast (lockless) page fault support for the new MMU
   - new MMU now the default
   - increased maximum allowed VCPU count
   - allow inhibit IRQs on KVM_RUN while debugging guests
   - let Hyper-V-enabled guests run with virtualized LAPIC as long as
     they do not enable the Hyper-V "AutoEOI" feature
   - fixes and optimizations for the toggling of AMD AVIC (virtualized
     LAPIC)
   - tuning for the case when two-dimensional paging (EPT/NPT) is
     disabled
   - bugfixes and cleanups, especially with respect to vCPU reset and
     choosing a paging mode based on CR0/CR4/EFER
   - support for 5-level page table on AMD processors

  Generic:
   - MMU notifier invalidation callbacks do not take mmu_lock unless
     necessary
   - improved caching of LRU kvm_memory_slot
   - support for histogram statistics
   - add statistics for halt polling and remote TLB flush requests"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (210 commits)
  KVM: Drop unused kvm_dirty_gfn_invalid()
  KVM: x86: Update vCPU's hv_clock before back to guest when tsc_offset is adjusted
  KVM: MMU: mark role_regs and role accessors as maybe unused
  KVM: MIPS: Remove a "set but not used" variable
  x86/kvm: Don't enable IRQ when IRQ enabled in kvm_wait
  KVM: stats: Add VM stat for remote tlb flush requests
  KVM: Remove unnecessary export of kvm_{inc,dec}_notifier_count()
  KVM: x86/mmu: Move lpage_disallowed_link further "down" in kvm_mmu_page
  KVM: x86/mmu: Relocate kvm_mmu_page.tdp_mmu_page for better cache locality
  Revert "KVM: x86: mmu: Add guest physical address check in translate_gpa()"
  KVM: x86/mmu: Remove unused field mmio_cached in struct kvm_mmu_page
  kvm: x86: Increase KVM_SOFT_MAX_VCPUS to 710
  kvm: x86: Increase MAX_VCPUS to 1024
  kvm: x86: Set KVM_MAX_VCPU_ID to 4*KVM_MAX_VCPUS
  KVM: VMX: avoid running vmx_handle_exit_irqoff in case of emulation
  KVM: x86/mmu: Don't freak out if pml5_root is NULL on 4-level host
  KVM: s390: index kvm->arch.idle_mask by vcpu_idx
  KVM: s390: Enable specification exception interpretation
  KVM: arm64: Trim guest debug exception handling
  KVM: SVM: Add 5-level page table support for SVM
  ...
2021-09-07 13:40:51 -07:00
Paolo Bonzini
e99314a340 KVM/arm64 updates for 5.15
- Page ownership tracking between host EL1 and EL2
 
 - Rely on userspace page tables to create large stage-2 mappings
 
 - Fix incompatibility between pKVM and kmemleak
 
 - Fix the PMU reset state, and improve the performance of the virtual PMU
 
 - Move over to the generic KVM entry code
 
 - Address PSCI reset issues w.r.t. save/restore
 
 - Preliminary rework for the upcoming pKVM fixed feature
 
 - A bunch of MM cleanups
 
 - a vGIC fix for timer spurious interrupts
 
 - Various cleanups
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Merge tag 'kvmarm-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 updates for 5.15

- Page ownership tracking between host EL1 and EL2

- Rely on userspace page tables to create large stage-2 mappings

- Fix incompatibility between pKVM and kmemleak

- Fix the PMU reset state, and improve the performance of the virtual PMU

- Move over to the generic KVM entry code

- Address PSCI reset issues w.r.t. save/restore

- Preliminary rework for the upcoming pKVM fixed feature

- A bunch of MM cleanups

- a vGIC fix for timer spurious interrupts

- Various cleanups
2021-09-06 06:34:48 -04:00
Alexey Kardashevskiy
1d78dfde33 KVM: PPC: Fix clearing never mapped TCEs in realmode
Since commit e1a1ef84cd ("KVM: PPC: Book3S: Allocate guest TCEs on
demand too"), pages for TCE tables for KVM guests are allocated only
when needed. This allows skipping any update when clearing TCEs. This
works mostly fine as TCE updates are handled when the MMU is enabled.
The realmode handlers fail with H_TOO_HARD when pages are not yet
allocated, except when clearing a TCE in which case KVM prints a warning
and proceeds to dereference a NULL pointer, which crashes the host OS.

This has not been caught so far as the change in commit e1a1ef84cd is
reasonably new, and POWER9 runs mostly radix which does not use realmode
handlers. With hash, the default TCE table is memset() by QEMU when the
machine is reset which triggers page faults and the KVM TCE device's
kvm_spapr_tce_fault() handles those with MMU on. And the huge DMA
windows are not cleared by VMs which instead successfully create a DMA
window big enough to map the VM memory 1:1 and then VMs just map
everything without clearing.

This started crashing now as commit 381ceda88c ("powerpc/pseries/iommu:
Make use of DDW for indirect mapping") added a mode when a dymanic DMA
window not big enough to map the VM memory 1:1 but it is used anyway,
and the VM now is the first (i.e. not QEMU) to clear a just created
table. Note that upstream QEMU needs to be modified to trigger the VM to
trigger the host OS crash.

This replaces WARN_ON_ONCE_RM() with a check and return, and adds
another warning if TCE is not being cleared.

Fixes: e1a1ef84cd ("KVM: PPC: Book3S: Allocate guest TCEs on demand too")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210827040706.517652-1-aik@ozlabs.ru
2021-08-30 13:51:43 +10:00
Michael Ellerman
465e333e77 Merge branch 'topic/ppc-kvm' into next
Merge some KVM patches we are keeping in a topic branch in case there
are any merge conflicts that need resolving.
2021-08-26 21:21:11 +10:00
Nicholas Piggin
0c8fb653d4 powerpc/64s: Remove WORT SPR from POWER9/10
This register is not architected and not implemented in POWER9 or 10,
it just reads back zeroes for compatibility.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Link: https://lore.kernel.org/r/20210811160134.904987-11-npiggin@gmail.com
2021-08-25 16:37:18 +10:00
Nicholas Piggin
1782663897 KVM: PPC: Book3S HV Nested: Reflect guest PMU in-use to L0 when guest SPRs are live
After the L1 saves its PMU SPRs but before loading the L2's PMU SPRs,
switch the pmcregs_in_use field in the L1 lppaca to the value advertised
by the L2 in its VPA. On the way out of the L2, set it back after saving
the L2 PMU registers (if they were in-use).

This transfers the PMU liveness indication between the L1 and L2 at the
points where the registers are not live.

This fixes the nested HV bug for which a workaround was added to the L0
HV by commit 63279eeb7f ("KVM: PPC: Book3S HV: Always save guest pmu
for guest capable of nesting"), which explains the problem in detail.
That workaround is no longer required for guests that include this bug
fix.

Fixes: 360cae3137 ("KVM: PPC: Book3S HV: Nested guest entry via hypercall")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Link: https://lore.kernel.org/r/20210811160134.904987-10-npiggin@gmail.com
2021-08-25 16:37:18 +10:00
Fabiano Rosas
f2e29db156 KVM: PPC: Book3S HV Nested: save_hv_return_state does not require trap argument
vcpu is already anargument so vcpu->arch.trap can be used directly.

Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-9-npiggin@gmail.com
2021-08-25 16:37:18 +10:00
Fabiano Rosas
7c3ded5735 KVM: PPC: Book3S HV Nested: Stop forwarding all HFUs to L1
If the nested hypervisor has no access to a facility because it has
been disabled by the host, it should also not be able to see the
Hypervisor Facility Unavailable that arises from one of its guests
trying to access the facility.

This patch turns a HFU that happened in L2 into a Hypervisor Emulation
Assistance interrupt and forwards it to L1 for handling. The ones that
happened because L1 explicitly disabled the facility for L2 are still
let through, along with the corresponding Cause bits in the HFSCR.

Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
[np: move handling into kvmppc_handle_nested_exit]
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-8-npiggin@gmail.com
2021-08-25 16:37:18 +10:00
Nicholas Piggin
8b210a880b KVM: PPC: Book3S HV Nested: Make nested HFSCR state accessible
When the L0 runs a nested L2, there are several permutations of HFSCR
that can be relevant. The HFSCR that the L1 vcpu L1 requested, the
HFSCR that the L1 vcpu may use, and the HFSCR that is actually being
used to run the L2.

The L1 requested HFSCR is not accessible outside the nested hcall
handler, so copy that into a new kvm_nested_guest.hfscr field.

The permitted HFSCR is taken from the HFSCR that the L1 runs with,
which is also not accessible while the hcall is being made. Move
this into a new kvm_vcpu_arch.hfscr_permitted field.

These will be used by the next patch to improve facility handling
for nested guests, and later by facility demand faulting patches.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-7-npiggin@gmail.com
2021-08-25 16:37:18 +10:00
Fabiano Rosas
7487cabc7e KVM: PPC: Book3S HV Nested: Sanitise vcpu registers
As one of the arguments of the H_ENTER_NESTED hypercall, the nested
hypervisor (L1) prepares a structure containing the values of various
hypervisor-privileged registers with which it wants the nested guest
(L2) to run. Since the nested HV runs in supervisor mode it needs the
host to write to these registers.

To stop a nested HV manipulating this mechanism and using a nested
guest as a proxy to access a facility that has been made unavailable
to it, we have a routine that sanitises the values of the HV registers
before copying them into the nested guest's vcpu struct.

However, when coming out of the guest the values are copied as they
were back into L1 memory, which means that any sanitisation we did
during guest entry will be exposed to L1 after H_ENTER_NESTED returns.

This patch alters this sanitisation to have effect on the vcpu->arch
registers directly before entering and after exiting the guest,
leaving the structure that is copied back into L1 unchanged (except
when we really want L1 to access the value, e.g the Cause bits of
HFSCR).

Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Link: https://lore.kernel.org/r/20210811160134.904987-6-npiggin@gmail.com
2021-08-25 16:37:17 +10:00
Nicholas Piggin
d82b392d9b KVM: PPC: Book3S HV Nested: Fix TM softpatch HFAC interrupt emulation
Have the TM softpatch emulation code set up the HFAC interrupt and
return -1 in case an instruction was executed with HFSCR bits clear,
and have the interrupt exit handler fall through to the HFAC handler.
When the L0 is running a nested guest, this ensures the HFAC interrupt
is correctly passed up to the L1.

The "direct guest" exit handler will turn these into PROGILL program
interrupts so functionality in practice will be unchanged. But it's
possible an L1 would want to handle these in a different way.

Also rearrange the FAC interrupt emulation code to match the HFAC format
while here (mainly, adding the FSCR_INTR_CAUSE mask).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-5-npiggin@gmail.com
2021-08-25 16:37:17 +10:00
Nicholas Piggin
4782e0cd0d KVM: PPC: Book3S HV P9: Fixes for TM softpatch interrupt NIP
The softpatch interrupt sets HSRR0 to the faulting instruction +4, so
it should subtract 4 for the faulting instruction address in the case
it is a TM softpatch interrupt (the instruction was not executed) and
it was not emulated.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-4-npiggin@gmail.com
2021-08-25 16:37:17 +10:00
Nicholas Piggin
daac40e8d7 KVM: PPC: Book3S HV: Remove TM emulation from POWER7/8 path
TM fake-suspend emulation is only used by POWER9. Remove it from the old
code path.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-3-npiggin@gmail.com
2021-08-25 16:37:17 +10:00
Nicholas Piggin
fd42b7b09c KVM: PPC: Book3S HV: Initialise vcpu MSR with MSR_ME
It is possible to create a VCPU without setting the MSR before running
it, which results in a warning in kvmhv_vcpu_entry_p9() that MSR_ME is
not set. This is pretty harmless because the MSR_ME bit is added to
HSRR1 before HRFID to guest, and a normal qemu guest doesn't hit it.

Initialise the vcpu MSR with MSR_ME set.

Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-2-npiggin@gmail.com
2021-08-25 16:37:17 +10:00
Fabiano Rosas
0eb596f1e6 KVM: PPC: Book3S HV: Stop exporting symbols from book3s_64_mmu_radix
The book3s_64_mmu_radix.o object is not part of the KVM builtins and
all the callers of the exported symbols are in the same kvm-hv.ko
module so we should not need to export any symbols.

Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210805212616.2641017-4-farosas@linux.ibm.com
2021-08-24 23:14:06 +10:00
Fabiano Rosas
c232461c0c KVM: PPC: Book3S HV: Add sanity check to copy_tofrom_guest
Both paths into __kvmhv_copy_tofrom_guest_radix ensure that we arrive
with an effective address that is smaller than our total addressable
space and addresses quadrant 0.

- The H_COPY_TOFROM_GUEST hypercall path rejects the call with
H_PARAMETER if the effective address has any of the twelve most
significant bits set.

- The kvmhv_copy_tofrom_guest_radix path clears the top twelve bits
before calling the internal function.

Although the callers make sure that the effective address is sane, any
future use of the function is exposed to a programming error, so add a
sanity check.

Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210805212616.2641017-3-farosas@linux.ibm.com
2021-08-24 23:14:06 +10:00
Fabiano Rosas
5d7d6dac8f KVM: PPC: Book3S HV: Fix copy_tofrom_guest routines
The __kvmhv_copy_tofrom_guest_radix function was introduced along with
nested HV guest support. It uses the platform's Radix MMU quadrants to
provide a nested hypervisor with fast access to its nested guests
memory (H_COPY_TOFROM_GUEST hypercall). It has also since been added
as a fast path for the kvmppc_ld/st routines which are used during
instruction emulation.

The commit def0bfdbd6 ("powerpc: use probe_user_read() and
probe_user_write()") changed the low level copy function from
raw_copy_from_user to probe_user_read, which adds a check to
access_ok. In powerpc that is:

 static inline bool __access_ok(unsigned long addr, unsigned long size)
 {
         return addr < TASK_SIZE_MAX && size <= TASK_SIZE_MAX - addr;
 }

and TASK_SIZE_MAX is 0x0010000000000000UL for 64-bit, which means that
setting the two MSBs of the effective address (which correspond to the
quadrant) now cause access_ok to reject the access.

This was not caught earlier because the most common code path via
kvmppc_ld/st contains a fallback (kvm_read_guest) that is likely to
succeed for L1 guests. For nested guests there is no fallback.

Another issue is that probe_user_read (now __copy_from_user_nofault)
does not return the number of bytes not copied in case of failure, so
the destination memory is not being cleared anymore in
kvmhv_copy_from_guest_radix:

 ret = kvmhv_copy_tofrom_guest_radix(vcpu, eaddr, to, NULL, n);
 if (ret > 0)                            <-- always false!
         memset(to + (n - ret), 0, ret);

This patch fixes both issues by skipping access_ok and open-coding the
low level __copy_to/from_user_inatomic.

Fixes: def0bfdbd6 ("powerpc: use probe_user_read() and probe_user_write()")
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210805212616.2641017-2-farosas@linux.ibm.com
2021-08-24 23:14:06 +10:00
Jing Zhang
8ccba534a1 KVM: stats: Add halt polling related histogram stats
Add three log histogram stats to record the distribution of time spent
on successful polling, failed polling and VCPU wait.
halt_poll_success_hist: Distribution of spent time for a successful poll.
halt_poll_fail_hist: Distribution of spent time for a failed poll.
halt_wait_hist: Distribution of time a VCPU has spent on waiting.

Signed-off-by: Jing Zhang <jingzhangos@google.com>
Message-Id: <20210802165633.1866976-6-jingzhangos@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-20 16:06:33 -04:00
Jing Zhang
87bcc5fa09 KVM: stats: Add halt_wait_ns stats for all architectures
Add simple stats halt_wait_ns to record the time a VCPU has spent on
waiting for all architectures (not just powerpc).

Signed-off-by: Jing Zhang <jingzhangos@google.com>
Message-Id: <20210802165633.1866976-5-jingzhangos@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-20 16:06:33 -04:00
Jing Zhang
f95937ccf5 KVM: stats: Support linear and logarithmic histogram statistics
Add new types of KVM stats, linear and logarithmic histogram.
Histogram are very useful for observing the value distribution
of time or size related stats.

Signed-off-by: Jing Zhang <jingzhangos@google.com>
Message-Id: <20210802165633.1866976-2-jingzhangos@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-20 16:06:32 -04:00
Cédric Le Goater
b352ddae7b KVM: PPC: Book3S PR: Remove unused variable
This fixes a compile error with W=1.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210819125656.14498-5-clg@kaod.org
2021-08-20 22:17:41 +10:00
Cédric Le Goater
cb53a93e33 KVM: PPC: Book3S PR: Declare kvmppc_handle_exit_pr()
This fixes a compile error with W=1.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210819125656.14498-4-clg@kaod.org
2021-08-20 22:17:38 +10:00
Lukas Bulwahn
c26d4c5d4f powerpc/kvm: Remove obsolete and unneeded select
Commit a278e7ea60 ("powerpc: Fix compile issue with force DAWR")
selects the non-existing config PPC_DAWR_FORCE_ENABLE for config
KVM_BOOK3S_64_HANDLER. As this commit also introduces a config PPC_DAWR
and this config PPC_DAWR is selected with PPC if PPC64, there is no
need for any further select in the KVM_BOOK3S_64_HANDLER.

Remove an obsolete and unneeded select in config KVM_BOOK3S_64_HANDLER.

The issue was identified with ./scripts/checkkconfigsymbols.py.

Fixes: a278e7ea60 ("powerpc: Fix compile issue with force DAWR")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210819113954.17515-2-lukas.bulwahn@gmail.com
2021-08-20 12:37:18 +10:00
Aneesh Kumar K.V
dbf77fed8b powerpc: rename powerpc_debugfs_root to arch_debugfs_dir
No functional change in this patch. arch_debugfs_dir is the generic kernel
name declared in linux/debugfs.h for arch-specific debugfs directory.
Architectures like x86/s390 already use the name. Rename powerpc
specific powerpc_debugfs_root to arch_debugfs_dir.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210812132831.233794-2-aneesh.kumar@linux.ibm.com
2021-08-13 22:04:26 +10:00
Cédric Le Goater
f5af0a9787 KVM: PPC: Book3S HV: XIVE: Add support for automatic save-restore
On P10, the feature doing an automatic "save & restore" of a VCPU
interrupt context is set by default in OPAL. When a VP context is
pulled out, the state of the interrupt registers are saved by the XIVE
interrupt controller under the internal NVP structure representing the
VP. This saves a costly store/load in guest entries and exits.

If OPAL advertises the "save & restore" feature in the device tree,
it should also have set the 'H' bit in the CAM line. Check that when
vCPUs are connected to their ICP in KVM before going any further.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210720134209.256133-3-clg@kaod.org
2021-08-10 23:15:02 +10:00
Cédric Le Goater
b68c6646cc KVM: PPC: Book3S HV: XIVE: Add a 'flags' field
Use it to hold platform specific features. P9 DD2 introduced
single-escalation support. P10 will add others.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210720134209.256133-2-clg@kaod.org
2021-08-10 23:15:01 +10:00
Cédric Le Goater
1753081f2d KVM: PPC: Book3S HV: XICS: Fix mapping of passthrough interrupts
PCI MSIs now live in an MSI domain but the underlying calls, which
will EOI the interrupt in real mode, need an HW IRQ number mapped in
the XICS IRQ domain. Grab it there.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210701132750.1475580-31-clg@kaod.org
2021-08-10 23:15:01 +10:00
Cédric Le Goater
c325712b5f powerpc/powernv/pci: Rework pnv_opal_pci_msi_eoi()
pnv_opal_pci_msi_eoi() is called from KVM to EOI passthrough interrupts
when in real mode. Adding MSI domain broke the hack using the
'ioda.irq_chip' field to deduce the owning PHB. Fix that by using the
IRQ chip data in the MSI domain.

The 'ioda.irq_chip' field is now unused and could be removed from the
pnv_phb struct.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210701132750.1475580-30-clg@kaod.org
2021-08-10 23:15:01 +10:00
Cédric Le Goater
51be9e51a8 KVM: PPC: Book3S HV: XIVE: Fix mapping of passthrough interrupts
PCI MSI interrupt numbers are now mapped in a PCI-MSI domain but the
underlying calls handling the passthrough of the interrupt in the
guest need a number in the XIVE IRQ domain.

Use the IRQ data mapped in the XIVE IRQ domain and not the one in the
PCI-MSI domain.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210701132750.1475580-16-clg@kaod.org
2021-08-10 23:14:59 +10:00
Cédric Le Goater
e5e78b1511 KVM: PPC: Book3S HV: XIVE: Change interface of passthrough interrupt routines
The routine kvmppc_set_passthru_irq() calls kvmppc_xive_set_mapped()
and kvmppc_xive_clr_mapped() with an IRQ descriptor. Use directly the
host IRQ number to remove a useless conversion.

Add some debug.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210701132750.1475580-15-clg@kaod.org
2021-08-10 23:14:59 +10:00
Cédric Le Goater
ba418a0278 KVM: PPC: Book3S HV: Use the new IRQ chip to detect passthrough interrupts
Passthrough PCI MSI interrupts are detected in KVM with a check on a
specific EOI handler (P8) or on XIVE (P9). We can now check the
PCI-MSI IRQ chip which is cleaner.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210701132750.1475580-14-clg@kaod.org
2021-08-10 23:14:58 +10:00
Alexey Kardashevskiy
2ac78e0c00 KVM: PPC: Use arch_get_random_seed_long instead of powernv variant
The powernv_get_random_long() does not work in nested KVM (which is
pseries) and produces a crash when accessing in_be64(rng->regs) in
powernv_get_random_long().

This replaces powernv_get_random_long with the ppc_md machine hook
wrapper.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210805075649.2086567-1-aik@ozlabs.ru
2021-08-10 23:14:56 +10:00
Sebastian Andrzej Siewior
5ae36401ca powerpc: Replace deprecated CPU-hotplug functions.
The functions get_online_cpus() and put_online_cpus() have been
deprecated during the CPU hotplug rework. They map directly to
cpus_read_lock() and cpus_read_unlock().

Replace deprecated CPU-hotplug functions with the official version.
The behavior remains unchanged.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210803141621.780504-4-bigeasy@linutronix.de
2021-08-10 23:14:56 +10:00
David Matlack
0f22af940d KVM: Move last_used_slot logic out of search_memslots
Make search_memslots unconditionally search all memslots and move the
last_used_slot logic up one level to __gfn_to_memslot. This is in
preparation for introducing a per-vCPU last_used_slot.

As part of this change convert existing callers of search_memslots to
__gfn_to_memslot to avoid making any functional changes.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210804222844.1419481-3-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-06 07:52:28 -04:00
Nicholas Piggin
d9c57d3ed5 KVM: PPC: Book3S HV Nested: Sanitise H_ENTER_NESTED TM state
The H_ENTER_NESTED hypercall is handled by the L0, and it is a request
by the L1 to switch the context of the vCPU over to that of its L2
guest, and return with an interrupt indication. The L1 is responsible
for switching some registers to guest context, and the L0 switches
others (including all the hypervisor privileged state).

If the L2 MSR has TM active, then the L1 is responsible for
recheckpointing the L2 TM state. Then the L1 exits to L0 via the
H_ENTER_NESTED hcall, and the L0 saves the TM state as part of the exit,
and then it recheckpoints the TM state as part of the nested entry and
finally HRFIDs into the L2 with TM active MSR. Not efficient, but about
the simplest approach for something that's horrendously complicated.

Problems arise if the L1 exits to the L0 with a TM state which does not
match the L2 TM state being requested. For example if the L1 is
transactional but the L2 MSR is non-transactional, or vice versa. The
L0's HRFID can take a TM Bad Thing interrupt and crash.

Fix this by disallowing H_ENTER_NESTED in TM[T] state entirely, and then
ensuring that if the L1 is suspended then the L2 must have TM active,
and if the L1 is not suspended then the L2 must not have TM active.

Fixes: 360cae3137 ("KVM: PPC: Book3S HV: Nested guest entry via hypercall")
Cc: stable@vger.kernel.org # v4.20+
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2021-07-23 16:19:38 +10:00
Nicholas Piggin
f62f3c2064 KVM: PPC: Book3S: Fix H_RTAS rets buffer overflow
The kvmppc_rtas_hcall() sets the host rtas_args.rets pointer based on
the rtas_args.nargs that was provided by the guest. That guest nargs
value is not range checked, so the guest can cause the host rets pointer
to be pointed outside the args array. The individual rtas function
handlers check the nargs and nrets values to ensure they are correct,
but if they are not, the handlers store a -3 (0xfffffffd) failure
indication in rets[0] which corrupts host memory.

Fix this by testing up front whether the guest supplied nargs and nret
would exceed the array size, and fail the hcall directly without storing
a failure indication to rets[0].

Also expand on a comment about why we kill the guest and try not to
return errors directly if we have a valid rets[0] pointer.

Fixes: 8e591cb720 ("KVM: PPC: Book3S: Add infrastructure to implement kernel-side RTAS calls")
Cc: stable@vger.kernel.org # v3.10+
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2021-07-23 16:14:31 +10:00
Nicholas Piggin
bc4188a2f5 KVM: PPC: Fix kvm_arch_vcpu_ioctl vcpu_load leak
vcpu_put is not called if the user copy fails. This can result in preempt
notifier corruption and crashes, among other issues.

Fixes: b3cebfe8c1 ("KVM: PPC: Move vcpu_load/vcpu_put down to each ioctl case in kvm_arch_vcpu_ioctl")
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210716024310.164448-2-npiggin@gmail.com
2021-07-17 14:33:18 +10:00
Nicholas Piggin
bd31ecf44b KVM: PPC: Book3S: Fix CONFIG_TRANSACTIONAL_MEM=n crash
When running CPU_FTR_P9_TM_HV_ASSIST, HFSCR[TM] is set for the guest
even if the host has CONFIG_TRANSACTIONAL_MEM=n, which causes it to be
unprepared to handle guest exits while transactional.

Normal guests don't have a problem because the HTM capability will not
be advertised, but a rogue or buggy one could crash the host.

Fixes: 4bb3c7a020 ("KVM: PPC: Book3S HV: Work around transactional memory bugs in POWER9")
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210716024310.164448-1-npiggin@gmail.com
2021-07-17 14:33:17 +10:00
Nicholas Piggin
e44fbdb680 KVM: PPC: Book3S HV P9: Fix guest TM support
The conversion to C introduced several bugs in TM handling that can
cause host crashes with TM bad thing interrupts. Mostly just simple
typos or missed logic in the conversion that got through due to my
not testing TM in the guest sufficiently.

- Early TM emulation for the softpatch interrupt should be done if fake
  suspend mode is _not_ active.

- Early TM emulation wants to return immediately to the guest so as to
  not doom transactions unnecessarily.

- And if exiting from the guest, the host MSR should include the TM[S]
  bit if the guest was T/S, before it is treclaimed.

After this fix, all the TM selftests pass when running on a P9 processor
that implements TM with softpatch interrupt.

Fixes: 89d35b2391 ("KVM: PPC: Book3S HV P9: Implement the rest of the P9 path in C")
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210712013650.376325-1-npiggin@gmail.com
2021-07-15 21:53:37 +10:00
Linus Torvalds
019b3fd94b powerpc updates for 5.14
- A big series refactoring parts of our KVM code, and converting some to C.
 
  - Support for ARCH_HAS_SET_MEMORY, and ARCH_HAS_STRICT_MODULE_RWX on some CPUs.
 
  - Support for the Microwatt soft-core.
 
  - Optimisations to our interrupt return path on 64-bit.
 
  - Support for userspace access to the NX GZIP accelerator on PowerVM on Power10.
 
  - Enable KUAP and KUEP by default on 32-bit Book3S CPUs.
 
  - Other smaller features, fixes & cleanups.
 
 Thanks to: Andy Shevchenko, Aneesh Kumar K.V, Arnd Bergmann, Athira Rajeev, Baokun Li,
 Benjamin Herrenschmidt, Bharata B Rao, Christophe Leroy, Daniel Axtens, Daniel Henrique
 Barboza, Finn Thain, Geoff Levand, Haren Myneni, Jason Wang, Jiapeng Chong, Joel Stanley,
 Jordan Niethe, Kajol Jain, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas
 Piggin, Nick Desaulniers, Paul Mackerras, Russell Currey, Sathvika Vasireddy, Shaokun
 Zhang, Stephen Rothwell, Sudeep Holla, Suraj Jitindar Singh, Tom Rix, Vaibhav Jain,
 YueHaibing, Zhang Jianhua, Zhen Lei.
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Merge tag 'powerpc-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - A big series refactoring parts of our KVM code, and converting some
   to C.

 - Support for ARCH_HAS_SET_MEMORY, and ARCH_HAS_STRICT_MODULE_RWX on
   some CPUs.

 - Support for the Microwatt soft-core.

 - Optimisations to our interrupt return path on 64-bit.

 - Support for userspace access to the NX GZIP accelerator on PowerVM on
   Power10.

 - Enable KUAP and KUEP by default on 32-bit Book3S CPUs.

 - Other smaller features, fixes & cleanups.

Thanks to: Andy Shevchenko, Aneesh Kumar K.V, Arnd Bergmann, Athira
Rajeev, Baokun Li, Benjamin Herrenschmidt, Bharata B Rao, Christophe
Leroy, Daniel Axtens, Daniel Henrique Barboza, Finn Thain, Geoff Levand,
Haren Myneni, Jason Wang, Jiapeng Chong, Joel Stanley, Jordan Niethe,
Kajol Jain, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas
Piggin, Nick Desaulniers, Paul Mackerras, Russell Currey, Sathvika
Vasireddy, Shaokun Zhang, Stephen Rothwell, Sudeep Holla, Suraj Jitindar
Singh, Tom Rix, Vaibhav Jain, YueHaibing, Zhang Jianhua, and Zhen Lei.

* tag 'powerpc-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (218 commits)
  powerpc: Only build restart_table.c for 64s
  powerpc/64s: move ret_from_fork etc above __end_soft_masked
  powerpc/64s/interrupt: clean up interrupt return labels
  powerpc/64/interrupt: add missing kprobe annotations on interrupt exit symbols
  powerpc/64: enable MSR[EE] in irq replay pt_regs
  powerpc/64s/interrupt: preserve regs->softe for NMI interrupts
  powerpc/64s: add a table of implicit soft-masked addresses
  powerpc/64e: remove implicit soft-masking and interrupt exit restart logic
  powerpc/64e: fix CONFIG_RELOCATABLE build warnings
  powerpc/64s: fix hash page fault interrupt handler
  powerpc/4xx: Fix setup_kuep() on SMP
  powerpc/32s: Fix setup_{kuap/kuep}() on SMP
  powerpc/interrupt: Use names in check_return_regs_valid()
  powerpc/interrupt: Also use exit_must_hard_disable() on PPC32
  powerpc/sysfs: Replace sizeof(arr)/sizeof(arr[0]) with ARRAY_SIZE
  powerpc/ptrace: Refactor regs_set_return_{msr/ip}
  powerpc/ptrace: Move set_return_regs_changed() before regs_set_return_{msr/ip}
  powerpc/stacktrace: Fix spurious "stale" traces in raise_backtrace_ipi()
  powerpc/pseries/vas: Include irqdomain.h
  powerpc: mark local variables around longjmp as volatile
  ...
2021-07-02 12:54:34 -07:00
Linus Torvalds
65090f30ab Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "191 patches.

  Subsystems affected by this patch series: kthread, ia64, scripts,
  ntfs, squashfs, ocfs2, kernel/watchdog, and mm (gup, pagealloc, slab,
  slub, kmemleak, dax, debug, pagecache, gup, swap, memcg, pagemap,
  mprotect, bootmem, dma, tracing, vmalloc, kasan, initialization,
  pagealloc, and memory-failure)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (191 commits)
  mm,hwpoison: make get_hwpoison_page() call get_any_page()
  mm,hwpoison: send SIGBUS with error virutal address
  mm/page_alloc: split pcp->high across all online CPUs for cpuless nodes
  mm/page_alloc: allow high-order pages to be stored on the per-cpu lists
  mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM
  mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA
  docs: remove description of DISCONTIGMEM
  arch, mm: remove stale mentions of DISCONIGMEM
  mm: remove CONFIG_DISCONTIGMEM
  m68k: remove support for DISCONTIGMEM
  arc: remove support for DISCONTIGMEM
  arc: update comment about HIGHMEM implementation
  alpha: remove DISCONTIGMEM and NUMA
  mm/page_alloc: move free_the_page
  mm/page_alloc: fix counting of managed_pages
  mm/page_alloc: improve memmap_pages dbg msg
  mm: drop SECTION_SHIFT in code comments
  mm/page_alloc: introduce vm.percpu_pagelist_high_fraction
  mm/page_alloc: limit the number of pages on PCP lists when reclaim is active
  mm/page_alloc: scale the number of pages that are batch freed
  ...
2021-06-29 17:29:11 -07:00
Linus Torvalds
21edf50948 Updates for the interrupt subsystem:
Core changes:
 
   - Cleanup and simplification of common code to invoke the low level
     interrupt flow handlers when this invocation requires irqdomain
     resolution. Add the necessary core infrastructure.
 
   - Provide a proper interface for modular PMU drivers to set the
     interrupt affinity.
 
   - Add a request flag which allows to exclude interrupts from spurious
     interrupt detection. Useful especially for IPI handlers which always
     return IRQ_HANDLED which turns the spurious interrupt detection into a
     pointless waste of CPU cycles.
 
 Driver changes:
 
   - Bulk convert interrupt chip drivers to the new irqdomain low level flow
     handler invocation mechanism.
 
   - Add device tree bindings for the Renesas R-Car M3-W+ SoC
 
   - Enable modular build of the Qualcomm PDC driver
 
   - The usual small fixes and improvements.
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Merge tag 'irq-core-2021-06-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq updates from Thomas Gleixner:
 "Updates for the interrupt subsystem:

  Core changes:

   - Cleanup and simplification of common code to invoke the low level
     interrupt flow handlers when this invocation requires irqdomain
     resolution. Add the necessary core infrastructure.

   - Provide a proper interface for modular PMU drivers to set the
     interrupt affinity.

   - Add a request flag which allows to exclude interrupts from spurious
     interrupt detection. Useful especially for IPI handlers which
     always return IRQ_HANDLED which turns the spurious interrupt
     detection into a pointless waste of CPU cycles.

  Driver changes:

   - Bulk convert interrupt chip drivers to the new irqdomain low level
     flow handler invocation mechanism.

   - Add device tree bindings for the Renesas R-Car M3-W+ SoC

   - Enable modular build of the Qualcomm PDC driver

   - The usual small fixes and improvements"

* tag 'irq-core-2021-06-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  dt-bindings: interrupt-controller: arm,gic-v3: Describe GICv3 optional properties
  irqchip: gic-pm: Remove redundant error log of clock bulk
  irqchip/sun4i: Remove unnecessary oom message
  irqchip/irq-imx-gpcv2: Remove unnecessary oom message
  irqchip/imgpdc: Remove unnecessary oom message
  irqchip/gic-v3-its: Remove unnecessary oom message
  irqchip/gic-v2m: Remove unnecessary oom message
  irqchip/exynos-combiner: Remove unnecessary oom message
  irqchip: Bulk conversion to generic_handle_domain_irq()
  genirq: Move non-irqdomain handle_domain_irq() handling into ARM's handle_IRQ()
  genirq: Add generic_handle_domain_irq() helper
  irqchip/nvic: Convert from handle_IRQ() to handle_domain_irq()
  irqdesc: Fix __handle_domain_irq() comment
  genirq: Use irq_resolve_mapping() to implement __handle_domain_irq() and co
  irqdomain: Introduce irq_resolve_mapping()
  irqdomain: Protect the linear revmap with RCU
  irqdomain: Cache irq_data instead of a virq number in the revmap
  irqdomain: Use struct_size() helper when allocating irqdomain
  irqdomain: Make normal and nomap irqdomains exclusive
  powerpc: Move the use of irq_domain_add_nomap() behind a config option
  ...
2021-06-29 12:25:04 -07:00
Liam Howlett
900c83f88a arch/powerpc/kvm/book3s: use vma_lookup() in kvmppc_hv_setup_htab_rma()
Using vma_lookup() removes the requirement to check if the address is
within the returned vma.  The code is easier to understand and more
compact.

Link: https://lkml.kernel.org/r/20210521174745.2219620-7-Liam.Howlett@Oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:51 -07:00
Liam Howlett
27a14d287e arch/powerpc/kvm/book3s_hv_uvmem: use vma_lookup() instead of find_vma_intersection()
vma_lookup() finds the vma of a specific address with a cleaner interface
and is more readable.

Link: https://lkml.kernel.org/r/20210521174745.2219620-6-Liam.Howlett@Oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:51 -07:00
Linus Torvalds
36824f198c ARM:
- Add MTE support in guests, complete with tag save/restore interface
 
 - Reduce the impact of CMOs by moving them in the page-table code
 
 - Allow device block mappings at stage-2
 
 - Reduce the footprint of the vmemmap in protected mode
 
 - Support the vGIC on dumb systems such as the Apple M1
 
 - Add selftest infrastructure to support multiple configuration
   and apply that to PMU/non-PMU setups
 
 - Add selftests for the debug architecture
 
 - The usual crop of PMU fixes
 
 PPC:
 
 - Support for the H_RPT_INVALIDATE hypercall
 
 - Conversion of Book3S entry/exit to C
 
 - Bug fixes
 
 S390:
 
 - new HW facilities for guests
 
 - make inline assembly more robust with KASAN and co
 
 x86:
 
 - Allow userspace to handle emulation errors (unknown instructions)
 
 - Lazy allocation of the rmap (host physical -> guest physical address)
 
 - Support for virtualizing TSC scaling on VMX machines
 
 - Optimizations to avoid shattering huge pages at the beginning of live migration
 
 - Support for initializing the PDPTRs without loading them from memory
 
 - Many TLB flushing cleanups
 
 - Refuse to load if two-stage paging is available but NX is not (this has
   been a requirement in practice for over a year)
 
 - A large series that separates the MMU mode (WP/SMAP/SMEP etc.) from
   CR0/CR4/EFER, using the MMU mode everywhere once it is computed
   from the CPU registers
 
 - Use PM notifier to notify the guest about host suspend or hibernate
 
 - Support for passing arguments to Hyper-V hypercalls using XMM registers
 
 - Support for Hyper-V TLB flush hypercalls and enlightened MSR bitmap on
   AMD processors
 
 - Hide Hyper-V hypercalls that are not included in the guest CPUID
 
 - Fixes for live migration of virtual machines that use the Hyper-V
   "enlightened VMCS" optimization of nested virtualization
 
 - Bugfixes (not many)
 
 Generic:
 
 - Support for retrieving statistics without debugfs
 
 - Cleanups for the KVM selftests API
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "This covers all architectures (except MIPS) so I don't expect any
  other feature pull requests this merge window.

  ARM:

   - Add MTE support in guests, complete with tag save/restore interface

   - Reduce the impact of CMOs by moving them in the page-table code

   - Allow device block mappings at stage-2

   - Reduce the footprint of the vmemmap in protected mode

   - Support the vGIC on dumb systems such as the Apple M1

   - Add selftest infrastructure to support multiple configuration and
     apply that to PMU/non-PMU setups

   - Add selftests for the debug architecture

   - The usual crop of PMU fixes

  PPC:

   - Support for the H_RPT_INVALIDATE hypercall

   - Conversion of Book3S entry/exit to C

   - Bug fixes

  S390:

   - new HW facilities for guests

   - make inline assembly more robust with KASAN and co

  x86:

   - Allow userspace to handle emulation errors (unknown instructions)

   - Lazy allocation of the rmap (host physical -> guest physical
     address)

   - Support for virtualizing TSC scaling on VMX machines

   - Optimizations to avoid shattering huge pages at the beginning of
     live migration

   - Support for initializing the PDPTRs without loading them from
     memory

   - Many TLB flushing cleanups

   - Refuse to load if two-stage paging is available but NX is not (this
     has been a requirement in practice for over a year)

   - A large series that separates the MMU mode (WP/SMAP/SMEP etc.) from
     CR0/CR4/EFER, using the MMU mode everywhere once it is computed
     from the CPU registers

   - Use PM notifier to notify the guest about host suspend or hibernate

   - Support for passing arguments to Hyper-V hypercalls using XMM
     registers

   - Support for Hyper-V TLB flush hypercalls and enlightened MSR bitmap
     on AMD processors

   - Hide Hyper-V hypercalls that are not included in the guest CPUID

   - Fixes for live migration of virtual machines that use the Hyper-V
     "enlightened VMCS" optimization of nested virtualization

   - Bugfixes (not many)

  Generic:

   - Support for retrieving statistics without debugfs

   - Cleanups for the KVM selftests API"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (314 commits)
  KVM: x86: rename apic_access_page_done to apic_access_memslot_enabled
  kvm: x86: disable the narrow guest module parameter on unload
  selftests: kvm: Allows userspace to handle emulation errors.
  kvm: x86: Allow userspace to handle emulation errors
  KVM: x86/mmu: Let guest use GBPAGES if supported in hardware and TDP is on
  KVM: x86/mmu: Get CR4.SMEP from MMU, not vCPU, in shadow page fault
  KVM: x86/mmu: Get CR0.WP from MMU, not vCPU, in shadow page fault
  KVM: x86/mmu: Drop redundant rsvd bits reset for nested NPT
  KVM: x86/mmu: Optimize and clean up so called "last nonleaf level" logic
  KVM: x86: Enhance comments for MMU roles and nested transition trickiness
  KVM: x86/mmu: WARN on any reserved SPTE value when making a valid SPTE
  KVM: x86/mmu: Add helpers to do full reserved SPTE checks w/ generic MMU
  KVM: x86/mmu: Use MMU's role to determine PTTYPE
  KVM: x86/mmu: Collapse 32-bit PAE and 64-bit statements for helpers
  KVM: x86/mmu: Add a helper to calculate root from role_regs
  KVM: x86/mmu: Add helper to update paging metadata
  KVM: x86/mmu: Don't update nested guest's paging bitmasks if CR0.PG=0
  KVM: x86/mmu: Consolidate reset_rsvds_bits_mask() calls
  KVM: x86/mmu: Use MMU role_regs to get LA57, and drop vCPU LA57 helper
  KVM: x86/mmu: Get nested MMU's root level from the MMU's role
  ...
2021-06-28 15:40:51 -07:00