Commit Graph

1058919 Commits

Author SHA1 Message Date
Linus Torvalds
f080815fdb Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
 "ARM64:

   - Fix constant sign extension affecting TCR_EL2 and preventing
     running on ARMv8.7 models due to spurious bits being set

   - Fix use of helpers using PSTATE early on exit by always sampling it
     as soon as the exit takes place

   - Move pkvm's 32bit handling into a common helper

  RISC-V:

   - Fix incorrect KVM_MAX_VCPUS value

   - Unmap stage2 mapping when deleting/moving a memslot

  x86:

   - Fix and downgrade BUG_ON due to uninitialized cache

   - Many APICv and MOVE_ENC_CONTEXT_FROM fixes

   - Correctly emulate TLB flushes around nested vmentry/vmexit and when
     the nested hypervisor uses VPID

   - Prevent modifications to CPUID after the VM has run

   - Other smaller bugfixes

  Generic:

   - Memslot handling bugfixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (44 commits)
  KVM: fix avic_set_running for preemptable kernels
  KVM: VMX: clear vmx_x86_ops.sync_pir_to_irr if APICv is disabled
  KVM: SEV: accept signals in sev_lock_two_vms
  KVM: SEV: do not take kvm->lock when destroying
  KVM: SEV: Prohibit migration of a VM that has mirrors
  KVM: SEV: Do COPY_ENC_CONTEXT_FROM with both VMs locked
  selftests: sev_migrate_tests: add tests for KVM_CAP_VM_COPY_ENC_CONTEXT_FROM
  KVM: SEV: move mirror status to destination of KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM
  KVM: SEV: initialize regions_list of a mirror VM
  KVM: SEV: cleanup locking for KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM
  KVM: SEV: do not use list_replace_init on an empty list
  KVM: x86: Use a stable condition around all VT-d PI paths
  KVM: x86: check PIR even for vCPUs with disabled APICv
  KVM: VMX: prepare sync_pir_to_irr for running with APICv disabled
  KVM: selftests: page_table_test: fix calculation of guest_test_phys_mem
  KVM: x86/mmu: Handle "default" period when selectively waking kthread
  KVM: MMU: shadow nested paging does not have PKU
  KVM: x86/mmu: Remove spurious TLB flushes in TDP MMU zap collapsible path
  KVM: x86/mmu: Use yield-safe TDP MMU root iter in MMU notifier unmapping
  KVM: X86: Use vcpu->arch.walk_mmu for kvm_mmu_invlpg()
  ...
2021-11-30 09:22:15 -08:00
Matthew Wilcox (Oracle)
d6e6a27d96 tools: Fix math.h breakage
Commit 98e1385ef2 ("include/linux/radix-tree.h: replace kernel.h with
the necessary inclusions") broke the radix tree test suite in two
different ways; first by including math.h which didn't exist in the
tools directory, and second by removing an implicit include of
spinlock.h before lockdep.h.  Fix both issues.

Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-30 09:14:42 -08:00
Paolo Bonzini
7cfc5c653b KVM: fix avic_set_running for preemptable kernels
avic_set_running() passes the current CPU to avic_vcpu_load(), albeit
via vcpu->cpu rather than smp_processor_id().  If the thread is migrated
while avic_set_running runs, the call to avic_vcpu_load() can use a stale
value for the processor id.  Avoid this by blocking preemption over the
entire execution of avic_set_running().

Reported-by: Sean Christopherson <seanjc@google.com>
Fixes: 8221c13700 ("svm: Manage vcpu load/unload when enable AVIC")
Cc: stable@vger.kernel.org
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 07:40:48 -05:00
Paolo Bonzini
e90e51d5f0 KVM: VMX: clear vmx_x86_ops.sync_pir_to_irr if APICv is disabled
There is nothing to synchronize if APICv is disabled, since neither
other vCPUs nor assigned devices can set PIR.ON.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 07:40:47 -05:00
Paolo Bonzini
c9d61dcb0b KVM: SEV: accept signals in sev_lock_two_vms
Generally, kvm->lock is not taken for a long time, but
sev_lock_two_vms is different: it takes vCPU locks
inside, so userspace can hold it back just by calling
a vCPU ioctl.  Play it safe and use mutex_lock_killable.

Message-Id: <20211123005036.2954379-13-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:54:15 -05:00
Paolo Bonzini
10a37929ef KVM: SEV: do not take kvm->lock when destroying
Taking the lock is useless since there are no other references,
and there are already accesses (e.g. to sev->enc_context_owner)
that do not take it.  So get rid of it.

Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211123005036.2954379-12-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:54:14 -05:00
Paolo Bonzini
17d44a96f0 KVM: SEV: Prohibit migration of a VM that has mirrors
VMs that mirror an encryption context rely on the owner to keep the
ASID allocated.  Performing a KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM
would cause a dangling ASID:

1. copy context from A to B (gets ref to A)
2. move context from A to L (moves ASID from A to L)
3. close L (releases ASID from L, B still references it)

The right way to do the handoff instead is to create a fresh mirror VM
on the destination first:

1. copy context from A to B (gets ref to A)
[later] 2. close B (releases ref to A)
3. move context from A to L (moves ASID from A to L)
4. copy context from L to M

So, catch the situation by adding a count of how many VMs are
mirroring this one's encryption context.

Fixes: 0b020f5af0 ("KVM: SEV: Add support for SEV-ES intra host migration")
Message-Id: <20211123005036.2954379-11-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:54:14 -05:00
Paolo Bonzini
bf42b02b19 KVM: SEV: Do COPY_ENC_CONTEXT_FROM with both VMs locked
Now that we have a facility to lock two VMs with deadlock
protection, use it for the creation of mirror VMs as well.  One of
COPY_ENC_CONTEXT_FROM(dst, src) and COPY_ENC_CONTEXT_FROM(src, dst)
would always fail, so the combination is nonsensical and it is okay to
return -EBUSY if it is attempted.

This sidesteps the question of what happens if a VM is
MOVE_ENC_CONTEXT_FROM'd at the same time as it is
COPY_ENC_CONTEXT_FROM'd: the locking prevents that from
happening.

Cc: Peter Gonda <pgonda@google.com>
Cc: Sean Christopherson <seanjc@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211123005036.2954379-10-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:54:13 -05:00
Paolo Bonzini
dc79c9f4eb selftests: sev_migrate_tests: add tests for KVM_CAP_VM_COPY_ENC_CONTEXT_FROM
I am putting the tests in sev_migrate_tests because the failure conditions are
very similar and some of the setup code can be reused, too.

The tests cover both successful creation of a mirror VM, and error
conditions.

Cc: Peter Gonda <pgonda@google.com>
Cc: Sean Christopherson <seanjc@google.com>
Message-Id: <20211123005036.2954379-9-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:54:13 -05:00
Paolo Bonzini
642525e3bd KVM: SEV: move mirror status to destination of KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM
Allow intra-host migration of a mirror VM; the destination VM will be
a mirror of the same ASID as the source.

Fixes: b56639318b ("KVM: SEV: Add support for SEV intra host migration")
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211123005036.2954379-8-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:54:12 -05:00
Paolo Bonzini
2b347a3878 KVM: SEV: initialize regions_list of a mirror VM
This was broken before the introduction of KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM,
but technically harmless because the region list was unused for a mirror
VM.  However, it is untidy and it now causes a NULL pointer access when
attempting to move the encryption context of a mirror VM.

Fixes: 54526d1fd5 ("KVM: x86: Support KVM VMs sharing SEV context")
Message-Id: <20211123005036.2954379-7-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:54:12 -05:00
Paolo Bonzini
501b580c02 KVM: SEV: cleanup locking for KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM
Encapsulate the handling of the migration_in_progress flag for both VMs in
two functions sev_lock_two_vms and sev_unlock_two_vms.  It does not matter
if KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM locks the destination struct kvm a bit
later, and this change 1) keeps the cleanup chain of labels smaller 2)
makes it possible for KVM_CAP_VM_COPY_ENC_CONTEXT_FROM to reuse the logic.

Cc: Peter Gonda <pgonda@google.com>
Cc: Sean Christopherson <seanjc@google.com>
Message-Id: <20211123005036.2954379-6-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:54:11 -05:00
Paolo Bonzini
4674164f0a KVM: SEV: do not use list_replace_init on an empty list
list_replace_init cannot be used if the source is an empty list,
because "new->next->prev = new" will overwrite "old->next":

				new				old
				prev = new, next = new		prev = old, next = old
new->next = old->next		prev = new, next = old		prev = old, next = old
new->next->prev = new		prev = new, next = old		prev = old, next = new
new->prev = old->prev		prev = old, next = old		prev = old, next = old
new->next->prev = new		prev = old, next = old		prev = new, next = new

The desired outcome instead would be to leave both old and new the same
as they were (two empty circular lists).  Use list_cut_before, which
already has the necessary check and is documented to discard the
previous contents of the list that will hold the result.

Fixes: b56639318b ("KVM: SEV: Add support for SEV intra host migration")
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211123005036.2954379-5-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:54:11 -05:00
Paolo Bonzini
53b7ca1a35 KVM: x86: Use a stable condition around all VT-d PI paths
Currently, checks for whether VT-d PI can be used refer to the current
status of the feature in the current vCPU; or they more or less pick
vCPU 0 in case a specific vCPU is not available.

However, these checks do not attempt to synchronize with changes to
the IRTE.  In particular, there is no path that updates the IRTE when
APICv is re-activated on vCPU 0; and there is no path to wakeup a CPU
that has APICv disabled, if the wakeup occurs because of an IRTE
that points to a posted interrupt.

To fix this, always go through the VT-d PI path as long as there are
assigned devices and APICv is available on both the host and the VM side.
Since the relevant condition was copied over three times, take the hint
and factor it into a separate function.

Suggested-by: Sean Christopherson <seanjc@google.com>
Cc: stable@vger.kernel.org
Reviewed-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Message-Id: <20211123004311.2954158-5-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:53:14 -05:00
Paolo Bonzini
37c4dbf337 KVM: x86: check PIR even for vCPUs with disabled APICv
The IRTE for an assigned device can trigger a POSTED_INTR_VECTOR even
if APICv is disabled on the vCPU that receives it.  In that case, the
interrupt will just cause a vmexit and leave the ON bit set together
with the PIR bit corresponding to the interrupt.

Right now, the interrupt would not be delivered until APICv is re-enabled.
However, fixing this is just a matter of always doing the PIR->IRR
synchronization, even if the vCPU has temporarily disabled APICv.

This is not a problem for performance, or if anything it is an
improvement.  First, in the common case where vcpu->arch.apicv_active is
true, one fewer check has to be performed.  Second, static_call_cond will
elide the function call if APICv is not present or disabled.  Finally,
in the case for AMD hardware we can remove the sync_pir_to_irr callback:
it is only needed for apic_has_interrupt_for_ppr, and that function
already has a fallback for !APICv.

Cc: stable@vger.kernel.org
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Message-Id: <20211123004311.2954158-4-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:52:39 -05:00
Paolo Bonzini
7e1901f6c8 KVM: VMX: prepare sync_pir_to_irr for running with APICv disabled
If APICv is disabled for this vCPU, assigned devices may still attempt to
post interrupts.  In that case, we need to cancel the vmentry and deliver
the interrupt with KVM_REQ_EVENT.  Extend the existing code that handles
injection of L1 interrupts into L2 to cover this case as well.

vmx_hwapic_irr_update is only called when APICv is active so it would be
confusing to add a check for vcpu->arch.apicv_active in there.  Instead,
just use vmx_set_rvi directly in vmx_sync_pir_to_irr.

Cc: stable@vger.kernel.org
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211123004311.2954158-3-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:51:58 -05:00
Maciej S. Szmigiero
81835ee113 KVM: selftests: page_table_test: fix calculation of guest_test_phys_mem
A kvm_page_table_test run with its default settings fails on VMX due to
memory region add failure:
> ==== Test Assertion Failure ====
>  lib/kvm_util.c:952: ret == 0
>  pid=10538 tid=10538 errno=17 - File exists
>     1  0x00000000004057d1: vm_userspace_mem_region_add at kvm_util.c:947
>     2  0x0000000000401ee9: pre_init_before_test at kvm_page_table_test.c:302
>     3   (inlined by) run_test at kvm_page_table_test.c:374
>     4  0x0000000000409754: for_each_guest_mode at guest_modes.c:53
>     5  0x0000000000401860: main at kvm_page_table_test.c:500
>     6  0x00007f82ae2d8554: ?? ??:0
>     7  0x0000000000401894: _start at ??:?
>  KVM_SET_USER_MEMORY_REGION IOCTL failed,
>  rc: -1 errno: 17
>  slot: 1 flags: 0x0
>  guest_phys_addr: 0xc0000000 size: 0x40000000

This is because the memory range that this test is trying to add
(0x0c0000000 - 0x100000000) conflicts with LAPIC mapping at 0x0fee00000.

Looking at the code it seems that guest_test_*phys*_mem variable gets
mistakenly overwritten with guest_test_*virt*_mem while trying to adjust
the former for alignment.
With the correct variable adjusted this test runs successfully.

Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Message-Id: <52e487458c3172923549bbcf9dfccfbe6faea60b.1637940473.git.maciej.szmigiero@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:12:13 -05:00
Sean Christopherson
f47491d7f3 KVM: x86/mmu: Handle "default" period when selectively waking kthread
Account for the '0' being a default, "let KVM choose" period, when
determining whether or not the recovery worker needs to be awakened in
response to userspace reducing the period.  Failure to do so results in
the worker not being awakened properly, e.g. when changing the period
from '0' to any small-ish value.

Fixes: 4dfe4f40d8 ("kvm: x86: mmu: Make NX huge page recovery period configurable")
Cc: stable@vger.kernel.org
Cc: Junaid Shahid <junaids@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211120015706.3830341-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:09:27 -05:00
Paolo Bonzini
28f091bc2f KVM: MMU: shadow nested paging does not have PKU
Initialize the mask for PKU permissions as if CR4.PKE=0, avoiding
incorrect interpretations of the nested hypervisor's page tables.

Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:09:26 -05:00
Sean Christopherson
4b85c921cd KVM: x86/mmu: Remove spurious TLB flushes in TDP MMU zap collapsible path
Drop the "flush" param and return values to/from the TDP MMU's helper for
zapping collapsible SPTEs.  Because the helper runs with mmu_lock held
for read, not write, it uses tdp_mmu_zap_spte_atomic(), and the atomic
zap handles the necessary remote TLB flush.

Similarly, because mmu_lock is dropped and re-acquired between zapping
legacy MMUs and zapping TDP MMUs, kvm_mmu_zap_collapsible_sptes() must
handle remote TLB flushes from the legacy MMU before calling into the TDP
MMU.

Fixes: e2209710cc ("KVM: x86/mmu: Skip rmap operations if rmaps not allocated")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211120045046.3940942-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:09:25 -05:00
Sean Christopherson
7533377215 KVM: x86/mmu: Use yield-safe TDP MMU root iter in MMU notifier unmapping
Use the yield-safe variant of the TDP MMU iterator when handling an
unmapping event from the MMU notifier, as most occurences of the event
allow yielding.

Fixes: e1eed5847b ("KVM: x86/mmu: Allow yielding during MMU notifier unmap/zap, if possible")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211120015008.3780032-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-30 03:09:25 -05:00
David Howells
ddca5b0eba netfs: Adjust docs after foliation
Adjust the netfslib docs in light of the foliation changes.

Also un-kdoc-mark netfs_skip_folio_read() since it's internal and isn't
part of the API.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
cc: Matthew Wilcox <willy@infradead.org>
cc: linux-cachefs@redhat.com
cc: linux-mm@kvack.org
Link: https://lore.kernel.org/r/163706992597.3179783.18360472879717076435.stgit@warthog.procyon.org.uk/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-29 10:10:26 -08:00
Linus Torvalds
d58071a8a7 Linux 5.16-rc3 v5.16-rc3 2021-11-28 14:09:19 -08:00
Linus Torvalds
d06c942efe Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull vhost,virtio,vdpa bugfixes from Michael Tsirkin:
 "Misc fixes all over the place.

  Revert of virtio used length validation series: the approach taken
  does not seem to work, breaking too many guests in the process. We'll
  need to do length validation using some other approach"

[ This merge also ends up reverting commit f7a36b03a7 ("vsock/virtio:
  suppress used length validation"), which came in through the
  networking tree in the meantime, and was part of that whole used
  length validation series   - Linus ]

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vdpa_sim: avoid putting an uninitialized iova_domain
  vhost-vdpa: clean irqs before reseting vdpa device
  virtio-blk: modify the value type of num in virtio_queue_rq()
  vhost/vsock: cleanup removing `len` variable
  vhost/vsock: fix incorrect used length reported to the guest
  Revert "virtio_ring: validate used buffer length"
  Revert "virtio-net: don't let virtio core to validate used length"
  Revert "virtio-blk: don't let virtio core to validate used length"
  Revert "virtio-scsi: don't let virtio core to validate used buffer length"
2021-11-28 11:58:52 -08:00
Linus Torvalds
9557e60b8c Merge tag 'x86-urgent-2021-11-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 build fix from Thomas Gleixner:
 "A single fix for a missing __init annotation of prepare_command_line()"

* tag 'x86-urgent-2021-11-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Mark prepare_command_line() __init
2021-11-28 09:24:50 -08:00
Linus Torvalds
97891bbf38 Merge tag 'sched-urgent-2021-11-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Thomas Gleixner:
 "A single scheduler fix to ensure that there is no stale KASAN shadow
  state left on the idle task's stack when a CPU is brought up after it
  was brought down before"

* tag 'sched-urgent-2021-11-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/scs: Reset task stack state in bringup_cpu()
2021-11-28 09:15:34 -08:00
Linus Torvalds
1ed1d3a3da Merge tag 'perf-urgent-2021-11-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fix from Thomas Gleixner:
 "A single fix for perf to prevent it from sending SIGTRAP to another
  task from a trace point event as it's not possible to deliver a
  synchronous signal to a different task from there"

* tag 'perf-urgent-2021-11-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Ignore sigtrap for tracepoints destined for other tasks
2021-11-28 09:10:54 -08:00
Linus Torvalds
d039f38801 Merge tag 'locking-urgent-2021-11-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Thomas Gleixner:
 "Two regression fixes for reader writer semaphores:

   - Plug a race in the lock handoff which is caused by inconsistency of
     the reader and writer path and can lead to corruption of the
     underlying counter.

   - down_read_trylock() is suboptimal when the lock is contended and
     multiple readers trylock concurrently. That's due to the initial
     value being read non-atomically which results in at least two
     compare exchange loops. Making the initial readout atomic reduces
     this significantly. Whith 40 readers by 11% in a benchmark which
     enforces contention on mmap_sem"

* tag 'locking-urgent-2021-11-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rwsem: Optimize down_read_trylock() under highly contended case
  locking/rwsem: Make handoff bit handling more consistent
2021-11-28 09:04:41 -08:00
Linus Torvalds
f8132d62a2 Merge tag 'trace-v5.16-rc2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull another tracing fix from Steven Rostedt:
 "Fix the fix of pid filtering

  The setting of the pid filtering flag tested the "trace only this pid"
  case twice, and ignored the "trace everything but this pid" case.

  The 5.15 kernel does things a little differently due to the new sparse
  pid mask introduced in 5.16, and as the bug was discovered running the
  5.15 kernel, and the first fix was initially done for that kernel,
  that fix handled both cases (only pid and all but pid), but the
  forward port to 5.16 created this bug"

* tag 'trace-v5.16-rc2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Test the 'Do not trace this pid' case in create event
2021-11-28 08:50:53 -08:00
Linus Torvalds
0757ca01d9 Merge tag 'iommu-fixes-v5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu fixes from Joerg Roedel:

 - Intel VT-d fixes:
     - Remove unused PASID_DISABLED
     - Fix RCU locking
     - Fix for the unmap_pages call-back

 - Rockchip RK3568 address mask fix

 - AMD IOMMUv2 log message clarification

* tag 'iommu-fixes-v5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/vt-d: Fix unmap_pages support
  iommu/vt-d: Fix an unbalanced rcu_read_lock/rcu_read_unlock()
  iommu/rockchip: Fix PAGE_DESC_HI_MASKs for RK3568
  iommu/amd: Clarify AMD IOMMUv2 initialization messages
  iommu/vt-d: Remove unused PASID_DISABLED
2021-11-28 07:17:38 -08:00
Linus Torvalds
3498e7f2bb Merge tag '5.16-rc2-ksmbd-fixes' of git://git.samba.org/ksmbd
Pull ksmbd fixes from Steve French:
 "Five ksmbd server fixes, four of them for stable:

   - memleak fix

   - fix for default data stream on filesystems that don't support xattr

   - error logging fix

   - session setup fix

   - minor doc cleanup"

* tag '5.16-rc2-ksmbd-fixes' of git://git.samba.org/ksmbd:
  ksmbd: fix memleak in get_file_stream_info()
  ksmbd: contain default data stream even if xattr is empty
  ksmbd: downgrade addition info error msg to debug in smb2_get_info_sec()
  docs: filesystem: cifs: ksmbd: Fix small layout issues
  ksmbd: Fix an error handling path in 'smb2_sess_setup()'
2021-11-27 14:49:35 -08:00
Guenter Roeck
00169a9245 vmxnet3: Use generic Kconfig option for page size limit
Use the architecture independent Kconfig option PAGE_SIZE_LESS_THAN_64KB
to indicate that VMXNET3 requires a page size smaller than 64kB.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-27 14:34:41 -08:00
Guenter Roeck
4eec7faf67 fs: ntfs: Limit NTFS_RW to page sizes smaller than 64k
NTFS_RW code allocates page size dependent arrays on the stack. This
results in build failures if the page size is 64k or larger.

  fs/ntfs/aops.c: In function 'ntfs_write_mst_block':
  fs/ntfs/aops.c:1311:1: error:
	the frame size of 2240 bytes is larger than 2048 bytes

Since commit f22969a660 ("powerpc/64s: Default to 64K pages for 64 bit
book3s") this affects ppc:allmodconfig builds, but other architectures
supporting page sizes of 64k or larger are also affected.

Increasing the maximum frame size for affected architectures just to
silence this error does not really help.  The frame size would have to
be set to a really large value for 256k pages.  Also, a large frame size
could potentially result in stack overruns in this code and elsewhere
and is therefore not desirable.  Make NTFS_RW dependent on page sizes
smaller than 64k instead.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-27 14:34:41 -08:00
Guenter Roeck
1f0e290cc5 arch: Add generic Kconfig option indicating page size smaller than 64k
NTFS_RW and VMXNET3 require a page size smaller than 64kB.  Add generic
Kconfig option for use outside architecture code to avoid architecture
specific Kconfig options in that code.

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-27 14:34:41 -08:00
Steven Rostedt (VMware)
27ff768fa2 tracing: Test the 'Do not trace this pid' case in create event
When creating a new event (via a module, kprobe, eprobe, etc), the
descriptors that are created must add flags for pid filtering if an
instance has pid filtering enabled, as the flags are used at the time the
event is executed to know if pid filtering should be done or not.

The "Only trace this pid" case was added, but a cut and paste error made
that case checked twice, instead of checking the "Trace all but this pid"
case.

Link: https://lore.kernel.org/all/202111280401.qC0z99JB-lkp@intel.com/

Fixes: 6cb206508b ("tracing: Check pid filtering when creating events")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-27 16:50:43 -05:00
Linus Torvalds
4f0dda359c Merge tag 'xfs-5.16-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fixes from Darrick Wong:
 "Fixes for a resource leak and a build robot complaint about totally
  dead code:

   - Fix buffer resource leak that could lead to livelock on corrupt fs.

   - Remove unused function xfs_inew_wait to shut up the build robots"

* tag 'xfs-5.16-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: remove xfs_inew_wait
  xfs: Fix the free logic of state in xfs_attr_node_hasname
2021-11-27 12:59:54 -08:00
Linus Torvalds
adfb743ac0 Merge tag 'iomap-5.16-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull iomap fixes from Darrick Wong:
 "A single iomap bug fix and a cleanup for 5.16-rc2.

  The bug fix changes how iomap deals with reading from an inline data
  region -- whereas the current code (incorrectly) lets the iomap read
  iter try for more bytes after reading the inline region (which zeroes
  the rest of the page!) and hopes the next iteration terminates, we
  surveyed the inlinedata implementations and realized that all
  inlinedata implementations also require that the inlinedata region end
  at EOF, so we can simply terminate the read.

  The second patch documents these assumptions in the code so that
  they're not subtle implications anymore, and cleans up some of the
  grosser parts of that function.

  Summary:

   - Fix an accounting problem where unaligned inline data reads can run
     off the end of the read iomap iterator. iomap has historically
     required that inline data mappings only exist at the end of a file,
     though this wasn't documented anywhere.

   - Document iomap_read_inline_data and change its return type to be
     appropriate for the information that it's actually returning"

* tag 'iomap-5.16-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: iomap_read_inline_data cleanup
  iomap: Fix inline extent handling in iomap_readpage
2021-11-27 12:50:03 -08:00
Linus Torvalds
86155d6b43 Merge tag 'trace-v5.16-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
 "Two fixes to event pid filtering:

   - Make sure newly created events reflect the current state of pid
     filtering

   - Take pid filtering into account when recording trigger events.
     (Also clean up the if statement to be cleaner)"

* tag 'trace-v5.16-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix pid filtering when triggers are attached
  tracing: Check pid filtering when creating events
2021-11-27 12:03:57 -08:00
Linus Torvalds
86799cdfbc Merge tag 'io_uring-5.16-2021-11-27' of git://git.kernel.dk/linux-block
Pull more io_uring fixes from Jens Axboe:
 "The locking fixup that was applied earlier this rc has both a deadlock
  and IRQ safety issue, let's get that ironed out before -rc3. This
  contains:

   - Link traversal locking fix (Pavel)

   - Cancelation fix (Pavel)

   - Relocate cond_resched() for huge buffer chain freeing, avoiding a
     softlockup warning (Ye)

   - Fix timespec validation (Ye)"

* tag 'io_uring-5.16-2021-11-27' of git://git.kernel.dk/linux-block:
  io_uring: Fix undefined-behaviour in io_issue_sqe
  io_uring: fix soft lockup when call __io_remove_buffers
  io_uring: fix link traversal locking
  io_uring: fail cancellation for EXITING tasks
2021-11-27 11:28:37 -08:00
Linus Torvalds
650c8edf53 Merge tag 'block-5.16-2021-11-27' of git://git.kernel.dk/linux-block
Pull more block fixes from Jens Axboe:
 "Turns out that the flushing out of pending fixes before the
  Thanksgiving break didn't quite work out in terms of timing, so here's
  a followup set of fixes:

   - rq_qos_done() should be called regardless of whether or not we're
     the final put of the request, it's not related to the freeing of
     the state. This fixes an IO stall with wbt that a few users have
     reported, a regression in this release.

   - Only define zram_wb_devops if it's used, fixing a compilation
     warning for some compilers"

* tag 'block-5.16-2021-11-27' of git://git.kernel.dk/linux-block:
  zram: only make zram_wb_devops for CONFIG_ZRAM_WRITEBACK
  block: call rq_qos_done() before ref check in batch completions
2021-11-27 11:19:42 -08:00
Linus Torvalds
9e9fbe44be Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
 "Twelve fixes, eleven in drivers (target, qla2xx, scsi_debug, mpt3sas,
  ufs). The core fix is a minor correction to the previous state update
  fix for the iscsi daemons"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: scsi_debug: Zero clear zones at reset write pointer
  scsi: core: sysfs: Fix setting device state to SDEV_RUNNING
  scsi: scsi_debug: Sanity check block descriptor length in resp_mode_select()
  scsi: target: configfs: Delete unnecessary checks for NULL
  scsi: target: core: Use RCU helpers for INQUIRY t10_alua_tg_pt_gp
  scsi: mpt3sas: Fix incorrect system timestamp
  scsi: mpt3sas: Fix system going into read-only mode
  scsi: mpt3sas: Fix kernel panic during drive powercycle test
  scsi: ufs: ufs-mediatek: Add put_device() after of_find_device_by_node()
  scsi: scsi_debug: Fix type in min_t to avoid stack OOB
  scsi: qla2xxx: edif: Fix off by one bug in qla_edif_app_getfcinfo()
  scsi: ufs: ufshpb: Fix warning in ufshpb_set_hpb_read_to_upiu()
2021-11-27 11:15:17 -08:00
Linus Torvalds
7413927713 Merge tag 'nfs-for-5.16-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client fixes from Trond Myklebust:
 "Highlights include:

  Stable fixes:

   - NFSv42: Fix pagecache invalidation after COPY/CLONE

  Bugfixes:

   - NFSv42: Don't fail clone() just because the server failed to return
     post-op attributes

   - SUNRPC: use different lockdep keys for INET6 and LOCAL

   - NFSv4.1: handle NFS4ERR_NOSPC from CREATE_SESSION

   - SUNRPC: fix header include guard in trace header"

* tag 'nfs-for-5.16-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  SUNRPC: use different lock keys for INET6 and LOCAL
  sunrpc: fix header include guard in trace header
  NFSv4.1: handle NFS4ERR_NOSPC by CREATE_SESSION
  NFSv42: Fix pagecache invalidation after COPY/CLONE
  NFS: Add a tracepoint to show the results of nfs_set_cache_invalid()
  NFSv42: Don't fail clone() unless the OP_CLONE operation failed
2021-11-27 10:33:55 -08:00
Linus Torvalds
52dc4c640a Merge tag 'erofs-for-5.16-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs
Pull erofs fix from Gao Xiang:
 "Fix an ABBA deadlock introduced by XArray conversion"

* tag 'erofs-for-5.16-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
  erofs: fix deadlock when shrink erofs slab
2021-11-27 10:27:35 -08:00
Linus Torvalds
7b65b798a6 Merge tag 'powerpc-5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
 "Fix KVM using a Power9 instruction on earlier CPUs, which could lead
  to the host SLB being incorrectly invalidated and a subsequent host
  crash.

  Fix kernel hardlockup on vmap stack overflow on 32-bit.

  Thanks to Christophe Leroy, Nicholas Piggin, and Fabiano Rosas"

* tag 'powerpc-5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/32: Fix hardlockup on vmap stack overflow
  KVM: PPC: Book3S HV: Prevent POWER7/8 TLB flush flushing SLB
2021-11-27 10:06:15 -08:00
Linus Torvalds
6be088036c Merge tag 'mips-fixes_5.16_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS fixes from Thomas Bogendoerfer:

 - build fix for ZSTD enabled configs

 - fix for preempt warning

 - fix for loongson FTLB detection

 - fix for page table level selection

* tag 'mips-fixes_5.16_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: use 3-level pgtable for 64KB page size on MIPS_VA_BITS_48
  MIPS: loongson64: fix FTLB configuration
  MIPS: Fix using smp_processor_id() in preemptible in show_cpuinfo()
  MIPS: boot/compressed/: add __ashldi3 to target for ZSTD compression
2021-11-27 09:50:31 -08:00
Ye Bin
f6223ff799 io_uring: Fix undefined-behaviour in io_issue_sqe
We got issue as follows:
================================================================================
UBSAN: Undefined behaviour in ./include/linux/ktime.h:42:14
signed integer overflow:
-4966321760114568020 * 1000000000 cannot be represented in type 'long long int'
CPU: 1 PID: 2186 Comm: syz-executor.2 Not tainted 4.19.90+ #12
Hardware name: linux,dummy-virt (DT)
Call trace:
 dump_backtrace+0x0/0x3f0 arch/arm64/kernel/time.c:78
 show_stack+0x28/0x38 arch/arm64/kernel/traps.c:158
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x170/0x1dc lib/dump_stack.c:118
 ubsan_epilogue+0x18/0xb4 lib/ubsan.c:161
 handle_overflow+0x188/0x1dc lib/ubsan.c:192
 __ubsan_handle_mul_overflow+0x34/0x44 lib/ubsan.c:213
 ktime_set include/linux/ktime.h:42 [inline]
 timespec64_to_ktime include/linux/ktime.h:78 [inline]
 io_timeout fs/io_uring.c:5153 [inline]
 io_issue_sqe+0x42c8/0x4550 fs/io_uring.c:5599
 __io_queue_sqe+0x1b0/0xbc0 fs/io_uring.c:5988
 io_queue_sqe+0x1ac/0x248 fs/io_uring.c:6067
 io_submit_sqe fs/io_uring.c:6137 [inline]
 io_submit_sqes+0xed8/0x1c88 fs/io_uring.c:6331
 __do_sys_io_uring_enter fs/io_uring.c:8170 [inline]
 __se_sys_io_uring_enter fs/io_uring.c:8129 [inline]
 __arm64_sys_io_uring_enter+0x490/0x980 fs/io_uring.c:8129
 invoke_syscall arch/arm64/kernel/syscall.c:53 [inline]
 el0_svc_common+0x374/0x570 arch/arm64/kernel/syscall.c:121
 el0_svc_handler+0x190/0x260 arch/arm64/kernel/syscall.c:190
 el0_svc+0x10/0x218 arch/arm64/kernel/entry.S:1017
================================================================================

As ktime_set only judge 'secs' if big than KTIME_SEC_MAX, but if we pass
negative value maybe lead to overflow.
To address this issue, we must check if 'sec' is negative.

Signed-off-by: Ye Bin <yebin10@huawei.com>
Link: https://lore.kernel.org/r/20211118015907.844807-1-yebin10@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-27 06:41:38 -07:00
Ye Bin
1d0254e6b4 io_uring: fix soft lockup when call __io_remove_buffers
I got issue as follows:
[ 567.094140] __io_remove_buffers: [1]start ctx=0xffff8881067bf000 bgid=65533 buf=0xffff8881fefe1680
[  594.360799] watchdog: BUG: soft lockup - CPU#2 stuck for 26s! [kworker/u32:5:108]
[  594.364987] Modules linked in:
[  594.365405] irq event stamp: 604180238
[  594.365906] hardirqs last  enabled at (604180237): [<ffffffff93fec9bd>] _raw_spin_unlock_irqrestore+0x2d/0x50
[  594.367181] hardirqs last disabled at (604180238): [<ffffffff93fbbadb>] sysvec_apic_timer_interrupt+0xb/0xc0
[  594.368420] softirqs last  enabled at (569080666): [<ffffffff94200654>] __do_softirq+0x654/0xa9e
[  594.369551] softirqs last disabled at (569080575): [<ffffffff913e1d6a>] irq_exit_rcu+0x1ca/0x250
[  594.370692] CPU: 2 PID: 108 Comm: kworker/u32:5 Tainted: G            L    5.15.0-next-20211112+ #88
[  594.371891] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014
[  594.373604] Workqueue: events_unbound io_ring_exit_work
[  594.374303] RIP: 0010:_raw_spin_unlock_irqrestore+0x33/0x50
[  594.375037] Code: 48 83 c7 18 53 48 89 f3 48 8b 74 24 10 e8 55 f5 55 fd 48 89 ef e8 ed a7 56 fd 80 e7 02 74 06 e8 43 13 7b fd fb bf 01 00 00 00 <e8> f8 78 474
[  594.377433] RSP: 0018:ffff888101587a70 EFLAGS: 00000202
[  594.378120] RAX: 0000000024030f0d RBX: 0000000000000246 RCX: 1ffffffff2f09106
[  594.379053] RDX: 0000000000000000 RSI: ffffffff9449f0e0 RDI: 0000000000000001
[  594.379991] RBP: ffffffff9586cdc0 R08: 0000000000000001 R09: fffffbfff2effcab
[  594.380923] R10: ffffffff977fe557 R11: fffffbfff2effcaa R12: ffff8881b8f3def0
[  594.381858] R13: 0000000000000246 R14: ffff888153a8b070 R15: 0000000000000000
[  594.382787] FS:  0000000000000000(0000) GS:ffff888399c00000(0000) knlGS:0000000000000000
[  594.383851] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  594.384602] CR2: 00007fcbe71d2000 CR3: 00000000b4216000 CR4: 00000000000006e0
[  594.385540] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  594.386474] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  594.387403] Call Trace:
[  594.387738]  <TASK>
[  594.388042]  find_and_remove_object+0x118/0x160
[  594.389321]  delete_object_full+0xc/0x20
[  594.389852]  kfree+0x193/0x470
[  594.390275]  __io_remove_buffers.part.0+0xed/0x147
[  594.390931]  io_ring_ctx_free+0x342/0x6a2
[  594.392159]  io_ring_exit_work+0x41e/0x486
[  594.396419]  process_one_work+0x906/0x15a0
[  594.399185]  worker_thread+0x8b/0xd80
[  594.400259]  kthread+0x3bf/0x4a0
[  594.401847]  ret_from_fork+0x22/0x30
[  594.402343]  </TASK>

Message from syslogd@localhost at Nov 13 09:09:54 ...
kernel:watchdog: BUG: soft lockup - CPU#2 stuck for 26s! [kworker/u32:5:108]
[  596.793660] __io_remove_buffers: [2099199]start ctx=0xffff8881067bf000 bgid=65533 buf=0xffff8881fefe1680

We can reproduce this issue by follow syzkaller log:
r0 = syz_io_uring_setup(0x401, &(0x7f0000000300), &(0x7f0000003000/0x2000)=nil, &(0x7f0000ff8000/0x4000)=nil, &(0x7f0000000280)=<r1=>0x0, &(0x7f0000000380)=<r2=>0x0)
sendmsg$ETHTOOL_MSG_FEATURES_SET(0xffffffffffffffff, &(0x7f0000003080)={0x0, 0x0, &(0x7f0000003040)={&(0x7f0000000040)=ANY=[], 0x18}}, 0x0)
syz_io_uring_submit(r1, r2, &(0x7f0000000240)=@IORING_OP_PROVIDE_BUFFERS={0x1f, 0x5, 0x0, 0x401, 0x1, 0x0, 0x100, 0x0, 0x1, {0xfffd}}, 0x0)
io_uring_enter(r0, 0x3a2d, 0x0, 0x0, 0x0, 0x0)

The reason above issue  is 'buf->list' has 2,100,000 nodes, occupied cpu lead
to soft lockup.
To solve this issue, we need add schedule point when do while loop in
'__io_remove_buffers'.
After add  schedule point we do regression, get follow data.
[  240.141864] __io_remove_buffers: [1]start ctx=0xffff888170603000 bgid=65533 buf=0xffff8881116fcb00
[  268.408260] __io_remove_buffers: [1]start ctx=0xffff8881b92d2000 bgid=65533 buf=0xffff888130c83180
[  275.899234] __io_remove_buffers: [2099199]start ctx=0xffff888170603000 bgid=65533 buf=0xffff8881116fcb00
[  296.741404] __io_remove_buffers: [1]start ctx=0xffff8881b659c000 bgid=65533 buf=0xffff8881010fe380
[  305.090059] __io_remove_buffers: [2099199]start ctx=0xffff8881b92d2000 bgid=65533 buf=0xffff888130c83180
[  325.415746] __io_remove_buffers: [1]start ctx=0xffff8881b92d1000 bgid=65533 buf=0xffff8881a17d8f00
[  333.160318] __io_remove_buffers: [2099199]start ctx=0xffff8881b659c000 bgid=65533 buf=0xffff8881010fe380
...

Fixes:8bab4c09f24e("io_uring: allow conditional reschedule for intensive iterators")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Link: https://lore.kernel.org/r/20211122024737.2198530-1-yebin10@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-27 06:41:32 -07:00
Steven Rostedt (VMware)
a55f224ff5 tracing: Fix pid filtering when triggers are attached
If a event is filtered by pid and a trigger that requires processing of
the event to happen is a attached to the event, the discard portion does
not take the pid filtering into account, and the event will then be
recorded when it should not have been.

Cc: stable@vger.kernel.org
Fixes: 3fdaf80f4a ("tracing: Implement event pid filtering")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-26 17:37:06 -05:00
Alex Williamson
86dc40c7ea iommu/vt-d: Fix unmap_pages support
When supporting only the .map and .unmap callbacks of iommu_ops,
the IOMMU driver can make assumptions about the size and alignment
used for mappings based on the driver provided pgsize_bitmap.  VT-d
previously used essentially PAGE_MASK for this bitmap as any power
of two mapping was acceptably filled by native page sizes.

However, with the .map_pages and .unmap_pages interface we're now
getting page-size and count arguments.  If we simply combine these
as (page-size * count) and make use of the previous map/unmap
functions internally, any size and alignment assumptions are very
different.

As an example, a given vfio device assignment VM will often create
a 4MB mapping at IOVA pfn [0x3fe00 - 0x401ff].  On a system that
does not support IOMMU super pages, the unmap_pages interface will
ask to unmap 1024 4KB pages at the base IOVA.  dma_pte_clear_level()
will recurse down to level 2 of the page table where the first half
of the pfn range exactly matches the entire pte level.  We clear the
pte, increment the pfn by the level size, but (oops) the next pte is
on a new page, so we exit the loop an pop back up a level.  When we
then update the pfn based on that higher level, we seem to assume
that the previous pfn value was at the start of the level.  In this
case the level size is 256K pfns, which we add to the base pfn and
get a results of 0x7fe00, which is clearly greater than 0x401ff,
so we're done.  Meanwhile we never cleared the ptes for the remainder
of the range.  When the VM remaps this range, we're overwriting valid
ptes and the VT-d driver complains loudly, as reported by the user
report linked below.

The fix for this seems relatively simple, if each iteration of the
loop in dma_pte_clear_level() is assumed to clear to the end of the
level pte page, then our next pfn should be calculated from level_pfn
rather than our working pfn.

Fixes: 3f34f12597 ("iommu/vt-d: Implement map/unmap_pages() iommu_ops callback")
Reported-by: Ajay Garg <ajaygargnsit@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Link: https://lore.kernel.org/all/20211002124012.18186-1-ajaygargnsit@gmail.com/
Link: https://lore.kernel.org/r/163659074748.1617923.12716161410774184024.stgit@omen
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20211126135556.397932-3-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2021-11-26 22:54:47 +01:00
Christophe JAILLET
4e5973dd27 iommu/vt-d: Fix an unbalanced rcu_read_lock/rcu_read_unlock()
If we return -EOPNOTSUPP, the rcu lock remains lock. This is spurious.
Go through the end of the function instead. This way, the missing
'rcu_read_unlock()' is called.

Fixes: 7afd7f6aa2 ("iommu/vt-d: Check FL and SL capability sanity in scalable mode")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/40cc077ca5f543614eab2a10e84d29dd190273f6.1636217517.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20211126135556.397932-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2021-11-26 22:54:47 +01:00