Paolo Bonzini [Tue, 25 Jan 2022 16:11:30 +0000 (11:11 -0500)]
KVM: SVM: improve split between svm_prepare_guest_switch and sev_es_prepare_guest_switch
KVM performs the VMSAVE to the host save area for both regular and SEV-ES
guests, so hoist it up to svm_prepare_guest_switch. And because
sev_es_prepare_guest_switch does not really need to know the details
of struct svm_cpu_data *, just pass it the pointer to the host save area
inside the HSAVE page.
KVM: x86: Skip APICv update if APICv is disable at the module level
Bail from the APICv update paths _before_ taking apicv_update_lock if
APICv is disabled at the module level. kvm_request_apicv_update() in
particular is invoked from multiple paths that can be reached without
APICv being enabled, e.g. svm_enable_irq_window(), and taking the
rw_sem for write when APICv is disabled may introduce unnecessary
contention and stalls.
KVM: x86: Drop NULL check on kvm_x86_ops.check_apicv_inhibit_reasons
Drop the useless NULL check on kvm_x86_ops.check_apicv_inhibit_reasons
when handling an APICv update, both VMX and SVM unconditionally implement
the helper and leave it non-NULL even if APICv is disabled at the module
level. The latter is a moot point now that __kvm_request_apicv_update()
is called if and only if enable_apicv is true.
Unexport __kvm_request_apicv_update(), it's not used by vendor code and
should never be used by vendor code. The only reason it's exposed at all
is because Hyper-V's SynIC needs to track how many auto-EOIs are in use,
and it's convenient to use apicv_update_lock to guard that tracking.
KVM: x86/mmu: Zap _all_ roots when unmapping gfn range in TDP MMU
Zap both valid and invalid roots when zapping/unmapping a gfn range, as
KVM must ensure it holds no references to the freed page after returning
from the unmap operation. Most notably, the TDP MMU doesn't zap invalid
roots in mmu_notifier callbacks. This leads to use-after-free and other
issues if the mmu_notifier runs to completion while an invalid root
zapper yields as KVM fails to honor the requirement that there must be
_no_ references to the page after the mmu_notifier returns.
The bug is most easily reproduced by hacking KVM to cause a collision
between set_nx_huge_pages() and kvm_mmu_notifier_release(), but the bug
exists between kvm_mmu_notifier_invalidate_range_start() and memslot
updates as well. Invalidating a root ensures pages aren't accessible by
the guest, and KVM won't read or write page data itself, but KVM will
trigger e.g. kvm_set_pfn_dirty() when zapping SPTEs, and thus completing
a zap of an invalid root _after_ the mmu_notifier returns is fatal.
KVM: x86/mmu: Move "invalid" check out of kvm_tdp_mmu_get_root()
Move the check for an invalid root out of kvm_tdp_mmu_get_root() and into
the one place it actually matters, tdp_mmu_next_root(), as the other user
already has an implicit validity check. A future bug fix will need to
get references to invalid roots to honor mmu_notifier requests; there's
no point in forcing what will be a common path to open code getting a
reference to a root.
KVM: x86/mmu: Use common TDP MMU zap helper for MMU notifier unmap hook
Use the common TDP MMU zap helper when handling an MMU notifier unmap
event, the two flows are semantically identical. Consolidate the code in
preparation for a future bug fix, as both kvm_tdp_mmu_unmap_gfn_range()
and __kvm_tdp_mmu_zap_gfn_range() are guilty of not zapping SPTEs in
invalid roots.
David Woodhouse [Mon, 25 Oct 2021 13:29:01 +0000 (14:29 +0100)]
KVM: x86/xen: Fix runstate updates to be atomic when preempting vCPU
There are circumstances whem kvm_xen_update_runstate_guest() should not
sleep because it ends up being called from __schedule() when the vCPU
is preempted:
To handle this, make it use the same trick as __kvm_xen_has_interrupt(),
of using the hva from the gfn_to_hva_cache directly. Then it can use
pagefault_disable() around the accesses and just bail out if the page
is absent (which is unlikely).
I almost switched to using a gfn_to_pfn_cache here and bailing out if
kvm_map_gfn() fails, like kvm_steal_time_set_preempted() does — but on
closer inspection it looks like kvm_map_gfn() will *always* fail in
atomic context for a page in IOMEM, which means it will silently fail
to make the update every single time for such guests, AFAICT. So I
didn't do it that way after all. And will probably fix that one too.
Maxim Levitsky [Mon, 7 Feb 2022 15:54:25 +0000 (17:54 +0200)]
KVM: x86: lapic: don't touch irr_pending in kvm_apic_update_apicv when inhibiting it
kvm_apic_update_apicv is called when AVIC is still active, thus IRR bits
can be set by the CPU after it is called, and don't cause the irr_pending
to be set to true.
Also logic in avic_kick_target_vcpu doesn't expect a race with this
function so to make it simple, just keep irr_pending set to true and
let the next interrupt injection to the guest clear it.
Maxim Levitsky [Mon, 7 Feb 2022 15:54:24 +0000 (17:54 +0200)]
KVM: x86: nSVM: deal with L1 hypervisor that intercepts interrupts but lets L2 control them
Fix a corner case in which the L1 hypervisor intercepts
interrupts (INTERCEPT_INTR) and either doesn't set
virtual interrupt masking (V_INTR_MASKING) or enters a
nested guest with EFLAGS.IF disabled prior to the entry.
In this case, despite the fact that L1 intercepts the interrupts,
KVM still needs to set up an interrupt window to wait before
injecting the INTR vmexit.
Currently the KVM instead enters an endless loop of 'req_immediate_exit'.
Exactly the same issue also happens for SMIs and NMI.
Fix this as well.
Note that on VMX, this case is impossible as there is only
'vmexit on external interrupts' execution control which either set,
in which case both host and guest's EFLAGS.IF
are ignored, or not set, in which case no VMexits are delivered.
Maxim Levitsky [Mon, 7 Feb 2022 15:54:22 +0000 (17:54 +0200)]
KVM: x86: nSVM: expose clean bit support to the guest
KVM already honours few clean bits thus it makes sense
to let the nested guest know about it.
Note that KVM also doesn't check if the hardware supports
clean bits, and therefore nested KVM was
already setting clean bits and L0 KVM
was already honouring them.
Maxim Levitsky [Mon, 7 Feb 2022 15:54:21 +0000 (17:54 +0200)]
KVM: x86: nSVM/nVMX: set nested_run_pending on VM entry which is a result of RSM
While RSM induced VM entries are not full VM entries,
they still need to be followed by actual VM entry to complete it,
unlike setting the nested state.
This patch fixes boot of hyperv and SMM enabled
windows VM running nested on KVM, which fail due
to this issue combined with lack of dirty bit setting.
Maxim Levitsky [Mon, 7 Feb 2022 15:54:20 +0000 (17:54 +0200)]
KVM: x86: nSVM: mark vmcb01 as dirty when restoring SMM saved state
While usually, restoring the smm state makes the KVM enter
the nested guest thus a different vmcb (vmcb02 vs vmcb01),
KVM should still mark it as dirty, since hardware
can in theory cache multiple vmcbs.
Failure to do so, combined with lack of setting the
nested_run_pending (which is fixed in the next patch),
might make KVM re-enter vmcb01, which was just exited from,
with completely different set of guest state registers
(SMM vs non SMM) and without proper dirty bits set,
which results in the CPU reusing stale IDTR pointer
which leads to a guest shutdown on any interrupt.
On the real hardware this usually doesn't happen,
but when running nested, L0's KVM does check and
honour few dirty bits, causing this issue to happen.
This patch fixes boot of hyperv and SMM enabled
windows VM running nested on KVM.
Maxim Levitsky [Mon, 7 Feb 2022 15:54:19 +0000 (17:54 +0200)]
KVM: x86: nSVM: fix potential NULL derefernce on nested migration
Turns out that due to review feedback and/or rebases
I accidentally moved the call to nested_svm_load_cr3 to be too early,
before the NPT is enabled, which is very wrong to do.
KVM can't even access guest memory at that point as nested NPT
is needed for that, and of course it won't initialize the walk_mmu,
which is main issue the patch was addressing.
Maxim Levitsky [Mon, 7 Feb 2022 15:54:18 +0000 (17:54 +0200)]
KVM: x86: SVM: don't passthrough SMAP/SMEP/PKE bits in !NPT && !gCR0.PG case
When the guest doesn't enable paging, and NPT/EPT is disabled, we
use guest't paging CR3's as KVM's shadow paging pointer and
we are technically in direct mode as if we were to use NPT/EPT.
In direct mode we create SPTEs with user mode permissions
because usually in the direct mode the NPT/EPT doesn't
need to restrict access based on guest CPL
(there are MBE/GMET extenstions for that but KVM doesn't use them).
In this special "use guest paging as direct" mode however,
and if CR4.SMAP/CR4.SMEP are enabled, that will make the CPU
fault on each access and KVM will enter endless loop of page faults.
Since page protection doesn't have any meaning in !PG case,
just don't passthrough these bits.
The fix is the same as was done for VMX in commit:
commit 656ec4a4928a ("KVM: VMX: fix SMEP and SMAP without EPT")
This fixes the boot of windows 10 without NPT for good.
(Without this patch, BSP boots, but APs were stuck in endless
loop of page faults, causing the VM boot with 1 CPU)
Revert "svm: Add warning message for AVIC IPI invalid target"
Remove a WARN on an "AVIC IPI invalid target" exit, the WARN is trivial
to trigger from guest as it will fail on any destination APIC ID that
doesn't exist from the guest's perspective.
Don't bother recording anything in the kernel log, the common tracepoint
for kvm_avic_incomplete_ipi() is sufficient for debugging.
Marc Zyngier [Tue, 8 Feb 2022 17:54:41 +0000 (17:54 +0000)]
Merge branch kvm-arm64/pmu-bl into kvmarm-master/next
* kvm-arm64/pmu-bl:
: .
: Improve PMU support on heterogeneous systems, courtesy of Alexandru Elisei
: .
KVM: arm64: Refuse to run VCPU if the PMU doesn't match the physical CPU
KVM: arm64: Add KVM_ARM_VCPU_PMU_V3_SET_PMU attribute
KVM: arm64: Keep a list of probed PMUs
KVM: arm64: Keep a per-VM pointer to the default PMU
perf: Fix wrong name in comment for struct perf_cpu_context
KVM: arm64: Do not change the PMU event filter after a VCPU has run
Alexandru Elisei [Thu, 27 Jan 2022 16:17:59 +0000 (16:17 +0000)]
KVM: arm64: Refuse to run VCPU if the PMU doesn't match the physical CPU
Userspace can assign a PMU to a VCPU with the KVM_ARM_VCPU_PMU_V3_SET_PMU
device ioctl. If the VCPU is scheduled on a physical CPU which has a
different PMU, the perf events needed to emulate a guest PMU won't be
scheduled in and the guest performance counters will stop counting. Treat
it as an userspace error and refuse to run the VCPU in this situation.
When KVM creates an event and there are more than one PMUs present on the
system, perf_init_event() will go through the list of available PMUs and
will choose the first one that can create the event. The order of the PMUs
in this list depends on the probe order, which can change under various
circumstances, for example if the order of the PMU nodes change in the DTB
or if asynchronous driver probing is enabled on the kernel command line
(with the driver_async_probe=armv8-pmu option).
Another consequence of this approach is that on heteregeneous systems all
virtual machines that KVM creates will use the same PMU. This might cause
unexpected behaviour for userspace: when a VCPU is executing on the
physical CPU that uses this default PMU, PMU events in the guest work
correctly; but when the same VCPU executes on another CPU, PMU events in
the guest will suddenly stop counting.
Fortunately, perf core allows user to specify on which PMU to create an
event by using the perf_event_attr->type field, which is used by
perf_init_event() as an index in the radix tree of available PMUs.
Add the KVM_ARM_VCPU_PMU_V3_CTRL(KVM_ARM_VCPU_PMU_V3_SET_PMU) VCPU
attribute to allow userspace to specify the arm_pmu that KVM will use when
creating events for that VCPU. KVM will make no attempt to run the VCPU on
the physical CPUs that share the PMU, leaving it up to userspace to manage
the VCPU threads' affinity accordingly.
To ensure that KVM doesn't expose an asymmetric system to the guest, the
PMU set for one VCPU will be used by all other VCPUs. Once a VCPU has run,
the PMU cannot be changed in order to avoid changing the list of available
events for a VCPU, or to change the semantics of existing events.
Alexandru Elisei [Thu, 27 Jan 2022 16:17:57 +0000 (16:17 +0000)]
KVM: arm64: Keep a list of probed PMUs
The ARM PMU driver calls kvm_host_pmu_init() after probing to tell KVM that
a hardware PMU is available for guest emulation. Heterogeneous systems can
have more than one PMU present, and the callback gets called multiple
times, once for each of them. Keep track of all the PMUs available to KVM,
as they're going to be needed later.
Alexandru Elisei [Thu, 27 Jan 2022 16:17:55 +0000 (16:17 +0000)]
perf: Fix wrong name in comment for struct perf_cpu_context
Commit 0793a61d4df8 ("performance counters: core code") added the perf
subsystem (then called Performance Counters) to Linux, creating the struct
perf_cpu_context. The comment for the struct referred to it as a "struct
perf_counter_cpu_context".
Commit cdd6c482c9ff ("perf: Do the big rename: Performance Counters ->
Performance Events") changed the comment to refer to a "struct
perf_event_cpu_context", which was still the wrong name for the struct.
Change the comment to say "struct perf_cpu_context".
Marc Zyngier [Thu, 27 Jan 2022 16:17:54 +0000 (16:17 +0000)]
KVM: arm64: Do not change the PMU event filter after a VCPU has run
Userspace can specify which events a guest is allowed to use with the
KVM_ARM_VCPU_PMU_V3_FILTER attribute. The list of allowed events can be
identified by a guest from reading the PMCEID{0,1}_EL0 registers.
Changing the PMU event filter after a VCPU has run can cause reads of the
registers performed before the filter is changed to return different values
than reads performed with the new event filter in place. The architecture
defines the two registers as read-only, and this behaviour contradicts
that.
Keep track when the first VCPU has run and deny changes to the PMU event
filter to prevent this from happening.
Oliver Upton [Tue, 8 Feb 2022 01:27:05 +0000 (01:27 +0000)]
KVM: arm64: Drop unused param from kvm_psci_version()
kvm_psci_version() consumes a pointer to struct kvm in addition to a
vcpu pointer. Drop the kvm pointer as it is unused. While the comment
suggests the explicit kvm pointer was useful for calling from hyp, there
exist no such callsite in hyp.
Marc Zyngier [Tue, 8 Feb 2022 15:20:16 +0000 (15:20 +0000)]
Merge branch kvm-arm64/selftest/vgic-5.18 into kvmarm-master/next
* kvm-arm64/selftest/vgic-5.18:
: .
: A bunch of selftest fixes, courtesy of Ricardo Koller
: .
kvm: selftests: aarch64: use a tighter assert in vgic_poke_irq()
kvm: selftests: aarch64: fix some vgic related comments
kvm: selftests: aarch64: fix the failure check in kvm_set_gsi_routing_irqchip_check
kvm: selftests: aarch64: pass vgic_irq guest args as a pointer
kvm: selftests: aarch64: fix assert in gicv3_access_reg
Ricardo Koller [Thu, 27 Jan 2022 03:08:58 +0000 (19:08 -0800)]
kvm: selftests: aarch64: use a tighter assert in vgic_poke_irq()
vgic_poke_irq() checks that the attr argument passed to the vgic device
ioctl is sane. Make this check tighter by moving it to after the last
attr update.
Ricardo Koller [Thu, 27 Jan 2022 03:08:56 +0000 (19:08 -0800)]
kvm: selftests: aarch64: fix the failure check in kvm_set_gsi_routing_irqchip_check
kvm_set_gsi_routing_irqchip_check(expect_failure=true) is used to check
the error code returned by the kernel when trying to setup an invalid
gsi routing table. The ioctl fails if "pin >= KVM_IRQCHIP_NUM_PINS", so
kvm_set_gsi_routing_irqchip_check() should test the error only when
"intid >= KVM_IRQCHIP_NUM_PINS+32". The issue is that the test check is
"intid >= KVM_IRQCHIP_NUM_PINS", so for a case like "intid =
KVM_IRQCHIP_NUM_PINS" the test wrongly assumes that the kernel will
return an error. Fix this by using the right check.
Ricardo Koller [Thu, 27 Jan 2022 03:08:55 +0000 (19:08 -0800)]
kvm: selftests: aarch64: pass vgic_irq guest args as a pointer
The guest in vgic_irq gets its arguments in a struct. This struct used
to fit nicely in a single register so vcpu_args_set() was able to pass
it by value by setting x0 with it. Unfortunately, this args struct grew
after some commits and some guest args became random (specically
kvm_supports_irqfd).
Fix this by passing the guest args as a pointer (after allocating some
guest memory for it).
Marc Zyngier [Tue, 8 Feb 2022 14:58:38 +0000 (14:58 +0000)]
Merge branch kvm-arm64/vmid-allocator into kvmarm-master/next
* kvm-arm64/vmid-allocator:
: .
: VMID allocation rewrite from Shameerali Kolothum Thodi, paving the
: way for pinned VMIDs and SVA.
: .
KVM: arm64: Make active_vmids invalid on vCPU schedule out
KVM: arm64: Align the VMID allocation with the arm64 ASID
KVM: arm64: Make VMID bits accessible outside of allocator
KVM: arm64: Introduce a new VMID allocator for KVM
Shameer Kolothum [Mon, 22 Nov 2021 12:18:44 +0000 (12:18 +0000)]
KVM: arm64: Make active_vmids invalid on vCPU schedule out
Like ASID allocator, we copy the active_vmids into the
reserved_vmids on a rollover. But it's unlikely that
every CPU will have a vCPU as current task and we may
end up unnecessarily reserving the VMID space.
Hence, set active_vmids to an invalid one when scheduling
out a vCPU.
Julien Grall [Mon, 22 Nov 2021 12:18:43 +0000 (12:18 +0000)]
KVM: arm64: Align the VMID allocation with the arm64 ASID
At the moment, the VMID algorithm will send an SGI to all the
CPUs to force an exit and then broadcast a full TLB flush and
I-Cache invalidation.
This patch uses the new VMID allocator. The benefits are:
- Aligns with arm64 ASID algorithm.
- CPUs are not forced to exit at roll-over. Instead,
the VMID will be marked reserved and context invalidation
is broadcasted. This will reduce the IPIs traffic.
- More flexible to add support for pinned KVM VMIDs in
the future.
With the new algo, the code is now adapted:
- The call to update_vmid() will be done with preemption
disabled as the new algo requires to store information
per-CPU.
Shameer Kolothum [Mon, 22 Nov 2021 12:18:42 +0000 (12:18 +0000)]
KVM: arm64: Make VMID bits accessible outside of allocator
Since we already set the kvm_arm_vmid_bits in the VMID allocator
init function, make it accessible outside as well so that it can
be used in the subsequent patch.
Shameer Kolothum [Mon, 22 Nov 2021 12:18:41 +0000 (12:18 +0000)]
KVM: arm64: Introduce a new VMID allocator for KVM
A new VMID allocator for arm64 KVM use. This is based on
arm64 ASID allocator algorithm.
One major deviation from the ASID allocator is the way we
flush the context. Unlike ASID allocator, we expect less
frequent rollover in the case of VMIDs. Hence, instead of
marking the CPU as flush_pending and issuing a local context
invalidation on the next context switch, we broadcast TLB
flush + I-cache invalidation over the inner shareable domain
on rollover.
Marc Zyngier [Tue, 8 Feb 2022 14:44:46 +0000 (14:44 +0000)]
Merge branch kvm-arm64/fpsimd-doc into kvmarm-master/next
* kvm-arm64/fpsimd-doc:
: .
: FPSIMD documentation update, courtesy of Mark Brown
: .
arm64/fpsimd: Clarify the purpose of using last in fpsimd_save()
KVM: arm64: Add some more comments in kvm_hyp_handle_fpsimd()
KVM: arm64: Add comments for context flush and sync callbacks
Mark Brown [Mon, 24 Jan 2022 16:11:15 +0000 (16:11 +0000)]
arm64/fpsimd: Clarify the purpose of using last in fpsimd_save()
When saving the floating point context in fpsimd_save() we always reference
the state using last-> rather than using current->. Looking at the FP code
in isolation the reason for this is not entirely obvious, it's done because
when KVM is running it will bind the guest context and rely on the host
writing out the guest state on context switch away from the guest.
There's a slight trick here in that KVM still uses TIF_FOREIGN_FPSTATE and
TIF_SVE to communicate what needs to be saved, it maintains those flags
and restores them when it is done running the guest so that the normal
restore paths function when we return back to userspace.
Add a comment to explain this to help future readers work out what's going
on a bit faster.
Mark Brown [Mon, 24 Jan 2022 15:57:20 +0000 (15:57 +0000)]
KVM: arm64: Add some more comments in kvm_hyp_handle_fpsimd()
The handling for FPSIMD/SVE traps is multi stage and involves some trap
manipulation which isn't quite so immediately obvious as might be desired
so add a few more comments.
Marc Zyngier [Tue, 8 Feb 2022 14:29:29 +0000 (14:29 +0000)]
Merge branch kvm-arm64/mmu-rwlock into kvmarm-master/next
* kvm-arm64/mmu-rwlock:
: .
: MMU locking optimisations from Jing Zhang, allowing permission
: relaxations to occur in parallel.
: .
KVM: selftests: Add vgic initialization for dirty log perf test for ARM
KVM: arm64: Add fast path to handle permission relaxation during dirty logging
KVM: arm64: Use read/write spin lock for MMU protection
Jing Zhang [Tue, 18 Jan 2022 01:57:01 +0000 (01:57 +0000)]
KVM: arm64: Use read/write spin lock for MMU protection
Replace MMU spinlock with rwlock and update all instances of the lock
being acquired with a write lock acquisition.
Future commit will add a fast path for permission relaxation during
dirty logging under a read lock.
Marc Zyngier [Tue, 8 Feb 2022 14:26:30 +0000 (14:26 +0000)]
Merge branch kvm-arm64/oslock into kvmarm-master/next
* kvm-arm64/oslock:
: .
: Debug OS-Lock emulation courtesy of Oliver Upton. From the cover letter:
:
: "KVM does not implement the debug architecture to the letter of the
: specification. One such issue is the fact that KVM treats the OS Lock as
: RAZ/WI, rather than emulating its behavior on hardware. This series adds
: emulation support for the OS Lock to KVM. Emulation is warranted as the
: OS Lock affects debug exceptions taken from all ELs, and is not limited
: to only the context of the guest."
: .
selftests: KVM: Test OS lock behavior
selftests: KVM: Add OSLSR_EL1 to the list of blessed regs
KVM: arm64: Emulate the OS Lock
KVM: arm64: Allow guest to set the OSLK bit
KVM: arm64: Stash OSLSR_EL1 in the cpu context
KVM: arm64: Correctly treat writes to OSLSR_EL1 as undefined
Oliver Upton [Thu, 3 Feb 2022 17:41:59 +0000 (17:41 +0000)]
selftests: KVM: Test OS lock behavior
KVM now correctly handles the OS Lock for its guests. When set, KVM
blocks all debug exceptions originating from the guest. Add test cases
to the debug-exceptions test to assert that software breakpoint,
hardware breakpoint, watchpoint, and single-step exceptions are in fact
blocked.
Oliver Upton [Thu, 3 Feb 2022 17:41:57 +0000 (17:41 +0000)]
KVM: arm64: Emulate the OS Lock
The OS lock blocks all debug exceptions at every EL. To date, KVM has
not implemented the OS lock for its guests, despite the fact that it is
mandatory per the architecture. Simple context switching between the
guest and host is not appropriate, as its effects are not constrained to
the guest context.
Emulate the OS Lock by clearing MDE and SS in MDSCR_EL1, thereby
blocking all but software breakpoint instructions.
Oliver Upton [Thu, 3 Feb 2022 17:41:55 +0000 (17:41 +0000)]
KVM: arm64: Stash OSLSR_EL1 in the cpu context
An upcoming change to KVM will emulate the OS Lock from the PoV of the
guest. Add OSLSR_EL1 to the cpu context and handle reads using the
stored value. Define some mnemonics for for handling the OSLM field and
use them to make the reset value of OSLSR_EL1 more readable.
Wire up a custom handler for writes from userspace and prevent any of
the invariant bits from changing. Note that the OSLK bit is not
invariant and will be made writable by the aforementioned change.
Oliver Upton [Thu, 3 Feb 2022 17:41:54 +0000 (17:41 +0000)]
KVM: arm64: Correctly treat writes to OSLSR_EL1 as undefined
Writes to OSLSR_EL1 are UNDEFINED and should never trap from EL1 to
EL2, but the kvm trap handler for OSLSR_EL1 handles writes via
ignore_write(). This is confusing to readers of code, but should have
no functional impact.
For clarity, use write_to_read_only() rather than ignore_write(). If a
trap is unexpectedly taken to EL2 in violation of the architecture, this
will WARN_ONCE() and inject an undef into the guest.
NeilBrown [Mon, 17 Jan 2022 05:36:53 +0000 (16:36 +1100)]
SUNRPC: lock against ->sock changing during sysfs read
->sock can be set to NULL asynchronously unless ->recv_mutex is held.
So it is important to hold that mutex. Otherwise a sysfs read can
trigger an oops.
Commit 17f09d3f619a ("SUNRPC: Check if the xprt is connected before
handling sysfs reads") appears to attempt to fix this problem, but it
only narrows the race window.
Fixes: 17f09d3f619a ("SUNRPC: Check if the xprt is connected before handling sysfs reads") Fixes: a8482488a7d6 ("SUNRPC query transport's source port") Signed-off-by: NeilBrown <[email protected]> Signed-off-by: Anna Schumaker <[email protected]>
Add the description of @server and @fhandle, and remove the excess
@inode in nfs4_proc_get_locations() kernel-doc comment to remove
warnings found by running scripts/kernel-doc, which is caused by
using 'make W=1'.
fs/nfs/nfs4proc.c:8219: warning: Function parameter or member 'server'
not described in 'nfs4_proc_get_locations'
fs/nfs/nfs4proc.c:8219: warning: Function parameter or member 'fhandle'
not described in 'nfs4_proc_get_locations'
fs/nfs/nfs4proc.c:8219: warning: Excess function parameter 'inode'
description in 'nfs4_proc_get_locations'
Dan Aloni [Tue, 25 Jan 2022 20:06:46 +0000 (22:06 +0200)]
xprtrdma: fix pointer derefs in error cases of rpcrdma_ep_create
If there are failures then we must not leave the non-NULL pointers with
the error value, otherwise `rpcrdma_ep_destroy` gets confused and tries
free them, resulting in an Oops.
Trond Myklebust [Wed, 2 Feb 2022 23:52:01 +0000 (18:52 -0500)]
NFS: Fix initialisation of nfs_client cl_flags field
For some long forgotten reason, the nfs_client cl_flags field is
initialised in nfs_get_client() instead of being initialised at
allocation time. This quirk was harmless until we moved the call to
nfs_create_rpc_client().
Fixes: dd99e9f98fbf ("NFSv4: Initialise connection to the server in nfs4_alloc_client()") Cc: [email protected] # 4.8.x Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Anna Schumaker <[email protected]>
Linus Torvalds [Mon, 7 Feb 2022 23:25:50 +0000 (15:25 -0800)]
Merge tag '5.17-rc3-ksmbd-server-fixes' of git://git.samba.org/ksmbd
Pull ksmbd server fixes from Steve French:
- NTLMSSP authentication improvement
- RDMA (smbdirect) fix allowing broader set of NICs to be supported
- improved buffer validation
- additional small fixes, including a posix extensions fix for stable
* tag '5.17-rc3-ksmbd-server-fixes' of git://git.samba.org/ksmbd:
ksmbd: add support for key exchange
ksmbd: reduce smb direct max read/write size
ksmbd: don't align last entry offset in smb2 query directory
ksmbd: fix same UniqueId for dot and dotdot entries
ksmbd: smbd: validate buffer descriptor structures
ksmbd: fix SMB 3.11 posix extension mount failure
* tag 'mmc-v5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
moxart: fix potential use-after-free on remove path
mmc: core: Wait for command setting 'Power Off Notification' bit to complete
mmc: sh_mmcif: Check for null res pointer
mmc: sdhci-of-esdhc: Check for error num after setting mask
Linus Torvalds [Mon, 7 Feb 2022 17:55:14 +0000 (09:55 -0800)]
Merge tag 'integrity-v5.17-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity fixes from Mimi Zohar:
"Fixes for recently found bugs.
One was found/noticed while reviewing IMA support for fsverity digests
and signatures. Two of them were found/noticed while working on IMA
namespacing. Plus two other bugs.
All of them are for previous kernel releases"
* tag 'integrity-v5.17-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
ima: Do not print policy rule with inactive LSM labels
ima: Allow template selection with ima_template[_fmt]= after ima_hash=
ima: Remove ima_policy file before directory
integrity: check the return value of audit_log_start()
ima: fix reference leak in asymmetric_verify()
Damien Le Moal [Mon, 7 Feb 2022 02:27:53 +0000 (11:27 +0900)]
ata: libata-core: Fix ata_dev_config_cpr()
The concurrent positioning ranges log page 47h is a general purpose log
page and not a subpage of the indentify device log. Using
ata_identify_page_supported() to test for concurrent positioning ranges
support is thus wrong. ata_log_supported() must be used.
Furthermore, unlike other advanced ATA features (e.g. NCQ priority),
accesses to the concurrent positioning ranges log page are not gated by
a feature bit from the device IDENTIFY data. Since many older drives
react badly to the READ LOG EXT and/or READ LOG DMA EXT commands isued
to read device log pages, avoid problems with older drives by limiting
the concurrent positioning ranges support detection to drives
implementing at least the ACS-4 ATA standard (major version 11). This
additional condition effectively turns ata_dev_config_cpr() into a nop
for older drives, avoiding problems in the field.
Linus Torvalds [Sun, 6 Feb 2022 18:34:45 +0000 (10:34 -0800)]
Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"Various bug fixes for ext4 fast commit and inline data handling.
Also fix regression introduced as part of moving to the new mount API"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
fs/ext4: fix comments mentioning i_mutex
ext4: fix incorrect type issue during replay_del_range
jbd2: fix kernel-doc descriptions for jbd2_journal_shrink_{scan,count}()
ext4: fix potential NULL pointer dereference in ext4_fill_super()
jbd2: refactor wait logic for transaction updates into a common function
jbd2: cleanup unused functions declarations from jbd2.h
ext4: fix error handling in ext4_fc_record_modified_inode()
ext4: remove redundant max inline_size check in ext4_da_write_inline_data_begin()
ext4: fix error handling in ext4_restore_inline_data()
ext4: fast commit may miss file actions
ext4: fast commit may not fallback for ineligible commit
ext4: modify the logic of ext4_mb_new_blocks_simple
ext4: prevent used blocks from being allocated during fast commit replay
Linus Torvalds [Sun, 6 Feb 2022 18:18:23 +0000 (10:18 -0800)]
Merge tag 'perf-tools-fixes-for-v5.17-2022-02-06' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix display of grouped aliased events in 'perf stat'.
- Add missing branch_sample_type to perf_event_attr__fprintf().
- Apply correct label to user/kernel symbols in branch mode.
- Fix 'perf ftrace' system_wide tracing, it has to be set before
creating the maps.
- Return error if procfs isn't mounted for PID namespaces when
synthesizing records for pre-existing processes.
- Set error stream of objdump process for 'perf annotate' TUI, to avoid
garbling the screen.
- Add missing arm64 support to perf_mmap__read_self(), the kernel part
got into 5.17.
- Check for NULL pointer before dereference writing debug info about a
sample.
- Update UAPI copies for asound, perf_event, prctl and kvm headers.
- Fix a typo in bpf_counter_cgroup.c.
* tag 'perf-tools-fixes-for-v5.17-2022-02-06' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf ftrace: system_wide collection is not effective by default
libperf: Add arm64 support to perf_mmap__read_self()
tools include UAPI: Sync sound/asound.h copy with the kernel sources
perf stat: Fix display of grouped aliased events
perf tools: Apply correct label to user/kernel symbols in branch mode
perf bpf: Fix a typo in bpf_counter_cgroup.c
perf synthetic-events: Return error if procfs isn't mounted for PID namespaces
perf session: Check for NULL pointer before dereference
perf annotate: Set error stream of objdump process for TUI
perf tools: Add missing branch_sample_type to perf_event_attr__fprintf()
tools headers UAPI: Sync linux/kvm.h with the kernel sources
tools headers UAPI: Sync linux/prctl.h with the kernel sources
perf beauty: Make the prctl arg regexp more strict to cope with PR_SET_VMA
tools headers cpufeatures: Sync with the kernel sources
tools headers UAPI: Sync linux/perf_event.h with the kernel sources
tools include UAPI: Sync sound/asound.h copy with the kernel sources
Linus Torvalds [Sun, 6 Feb 2022 18:11:14 +0000 (10:11 -0800)]
Merge tag 'perf_urgent_for_v5.17_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Borislav Petkov:
- Intel/PT: filters could crash the kernel
- Intel: default disable the PMU for SMM, some new-ish EFI firmware has
started using CPL3 and the PMU CPL filters don't discriminate against
SMM, meaning that CPL3 (userspace only) events now also count EFI/SMM
cycles.
- Fixup for perf_event_attr::sig_data
* tag 'perf_urgent_for_v5.17_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/pt: Fix crash with stop filters in single-range mode
perf: uapi: Document perf_event_attr::sig_data truncation on 32 bit architectures
selftests/perf_events: Test modification of perf_event_attr::sig_data
perf: Copy perf_event_attr::sig_data on modification
x86/perf: Default set FREEZE_ON_SMI for all
Linus Torvalds [Sun, 6 Feb 2022 17:57:39 +0000 (09:57 -0800)]
Merge tag 'edac_urgent_for_v5.17_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras
Pull EDAC fixes from Borislav Petkov:
"Fix altera and xgene EDAC drivers to propagate the correct error code
from platform_get_irq() so that deferred probing still works"
* tag 'edac_urgent_for_v5.17_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/xgene: Fix deferred probing
EDAC/altera: Fix deferred probing
Rob Herring [Tue, 1 Feb 2022 21:40:56 +0000 (15:40 -0600)]
libperf: Add arm64 support to perf_mmap__read_self()
Add the arm64 variants for read_perf_counter() and read_timestamp().
Unfortunately the counter number is encoded into the instruction, so the
code is a bit verbose to enumerate all possible counters.
Which entails no changes in the tooling side as it doesn't introduce new
SNDRV_PCM_IOCTL_ ioctls.
To silence this perf tools build warning:
Warning: Kernel ABI header at 'tools/include/uapi/sound/asound.h' differs from latest version at 'include/uapi/sound/asound.h'
diff -u tools/include/uapi/sound/asound.h include/uapi/sound/asound.h
Ian Rogers [Sat, 5 Feb 2022 01:09:41 +0000 (17:09 -0800)]
perf stat: Fix display of grouped aliased events
An event may have a number of uncore aliases that when added to the
evlist are consecutive.
If there are multiple uncore events in a group then
parse_events__set_leader_for_uncore_aliase will reorder the evlist so
that events on the same PMU are adjacent.
The collect_all_aliases function assumes that aliases are in blocks so
that only the first counter is printed and all others are marked merged.
The reordering for groups breaks the assumption and so all counts are
printed.
This change removes the assumption from collect_all_aliases
that the events are in blocks and instead processes the entire evlist.
Before:
```
$ perf stat -e '{UNC_CHA_TOR_OCCUPANCY.IA_MISS_DRD_REMOTE,UNC_CHA_TOR_INSERTS.IA_MISS_DRD_REMOTE},duration_time' -a -A -- sleep 1
Leo Yan [Fri, 24 Dec 2021 12:40:13 +0000 (20:40 +0800)]
perf synthetic-events: Return error if procfs isn't mounted for PID namespaces
For perf recording, it retrieves process info by iterating nodes in proc
fs. If we run perf in a non-root PID namespace with command:
# unshare --fork --pid perf record -e cycles -a -- test_program
... in this case, unshare command creates a child PID namespace and
launches perf tool in it, but the issue is the proc fs is not mounted
for the non-root PID namespace, this leads to the perf tool gathering
process info from its parent PID namespace.
We can use below command to observe the process nodes under proc fs:
So it shows many existed tasks, since unshared command has not mounted
the proc fs for the new created PID namespace, it still accesses the
proc fs of the root PID namespace. This leads to two prominent issues:
- Firstly, PID values are mismatched between thread info and samples.
The gathered thread info are coming from the proc fs of the root PID
namespace, but samples record its PID from the child PID namespace.
- The second issue is profiled program 'test_program' returns its forked
PID number from the child PID namespace, perf tool wrongly uses this
PID number to retrieve the process info via the proc fs of the root
PID namespace.
To avoid issues, we need to mount proc fs for the child PID namespace
with the option '--mount-proc' when use unshare command:
# unshare --fork --pid --mount-proc perf record -e cycles -a -- test_program
Conversely, when the proc fs of the root PID namespace is used by child
namespace, perf tool can detect the multiple PID levels and
nsinfo__is_in_root_namespace() returns false, this patch reports error
for this case:
# unshare --fork --pid perf record -e cycles -a -- test_program
Couldn't synthesize bpf events.
Perf runs in non-root PID namespace but it tries to gather process info from its parent PID namespace.
Please mount the proc file system properly, e.g. add the option '--mount-proc' for unshare command.
tools headers UAPI: Sync linux/kvm.h with the kernel sources
To pick the changes in:
f6c6804c43fa18d3 ("kvm: Move KVM_GET_XSAVE2 IOCTL definition at the end of kvm.h")
That just rebuilds perf, as these patches don't add any new KVM ioctl to
be harvested for the the 'perf trace' ioctl syscall argument
beautifiers.
This is also by now used by tools/testing/selftests/kvm/, a simple test
build succeeded.
This silences this perf build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h'
diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h
Linus Torvalds [Sat, 5 Feb 2022 17:55:59 +0000 (09:55 -0800)]
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"ARM:
- A couple of fixes when handling an exception while a SError has
been delivered
- Workaround for Cortex-A510's single-step erratum
RISC-V:
- Make CY, TM, and IR counters accessible in VU mode
- Fix SBI implementation version
x86:
- Report deprecation of x87 features in supported CPUID
- Preparation for fixing an interrupt delivery race on AMD hardware
- Sparse fix
All except POWER and s390:
- Rework guest entry code to correctly mark noinstr areas and fix
vtime' accounting (for x86, this was already mostly correct but not
entirely; for ARM, MIPS and RISC-V it wasn't)"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: Use ERR_PTR_USR() to return -EFAULT as a __user pointer
KVM: x86: Report deprecated x87 features in supported CPUID
KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errata
KVM: arm64: Stop handle_exit() from handling HVC twice when an SError occurs
KVM: arm64: Avoid consuming a stale esr value when SError occur
RISC-V: KVM: Fix SBI implementation version
RISC-V: KVM: make CY, TM, and IR counters accessible in VU mode
kvm/riscv: rework guest entry logic
kvm/arm64: rework guest entry logic
kvm/x86: rework guest entry logic
kvm/mips: rework guest entry logic
kvm: add guest_state_{enter,exit}_irqoff()
KVM: x86: Move delivery of non-APICv interrupt into vendor code
kvm: Move KVM_GET_XSAVE2 IOCTL definition at the end of kvm.h
Linus Torvalds [Sat, 5 Feb 2022 17:21:55 +0000 (09:21 -0800)]
Merge tag 'xfs-5.17-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fixes from Darrick Wong:
"I was auditing operations in XFS that clear file privileges, and
realized that XFS' fallocate implementation drops suid/sgid but
doesn't clear file capabilities the same way that file writes and
reflink do.
There are VFS helpers that do it correctly, so refactor XFS to use
them. I also noticed that we weren't flushing the log at the correct
point in the fallocate operation, so that's fixed too.
Summary:
- Fix fallocate so that it drops all file privileges when files are
modified instead of open-coding that incompletely.
- Fix fallocate to flush the log if the caller wanted synchronous
file updates"
* tag 'xfs-5.17-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: ensure log flush at the end of a synchronous fallocate call
xfs: move xfs_update_prealloc_flags() to xfs_pnfs.c
xfs: set prealloc flag in xfs_alloc_file_space()
xfs: fallocate() should call file_modified()
xfs: remove XFS_PREALLOC_SYNC
xfs: reject crazy array sizes being fed to XFS_IOC_GETBMAP*
Linus Torvalds [Sat, 5 Feb 2022 17:13:51 +0000 (09:13 -0800)]
Merge tag 'vfs-5.17-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull vfs fixes from Darrick Wong:
"I was auditing the sync_fs code paths recently and noticed that most
callers of ->sync_fs ignore its return value (and many implementations
never return nonzero even if the fs is broken!), which means that
internal fs errors and corruption are not passed up to userspace
callers of syncfs(2) or FIFREEZE. Hence fixing the common code and
XFS, and I'll start working on the ext4/btrfs folks if this is merged.
Summary:
- Fix a bug where callers of ->sync_fs (e.g. sync_filesystem and
syncfs(2)) ignore the return value.
- Fix a bug where callers of sync_filesystem (e.g. fs freeze) ignore
the return value.
- Fix a bug in XFS where xfs_fs_sync_fs never passed back error
returns"
* tag 'vfs-5.17-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: return errors in xfs_fs_sync_fs
quota: make dquot_quota_sync return errors from ->sync_fs
vfs: make sync_filesystem return errors from ->sync_fs
vfs: make freeze_super abort when sync_filesystem returns error
Linus Torvalds [Sat, 5 Feb 2022 17:04:43 +0000 (09:04 -0800)]
Merge tag 'iomap-5.17-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull iomap fix from Darrick Wong:
"A single bugfix for iomap.
The fix should eliminate occasional complaints about stall warnings
when a lot of writeback IO completes all at once and we have to then
go clearing status on a large number of folios.
Summary:
- Limit the length of ioend chains in writeback so that we don't trip
the softlockup watchdog and to limit long tail latency on clearing
PageWriteback"
* tag 'iomap-5.17-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs, iomap: limit individual ioend chain lengths in writeback
Linus Torvalds [Fri, 4 Feb 2022 23:27:45 +0000 (15:27 -0800)]
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Seven fixes, six of which are fairly obvious driver fixes.
The one core change to the device budget depth is to try to ensure
that if the default depth is large (which can produce quite a sizeable
bitmap allocation per device), we give back the memory we don't need
if there's a queue size reduction in slave_configure (which happens to
a lot of devices)"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: hisi_sas: Fix setting of hisi_sas_slot.is_internal
scsi: pm8001: Fix use-after-free for aborted SSP/STP sas_task
scsi: pm8001: Fix use-after-free for aborted TMF sas_task
scsi: pm8001: Fix warning for undescribed param in process_one_iomb()
scsi: core: Reallocate device's budget map on queue depth change
scsi: bnx2fc: Make bnx2fc_recv_frame() mp safe
scsi: pm80xx: Fix double completion for SATA devices