Age | Commit message (Collapse) | Author |
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git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm updates for 5.2
- guest SVE support
- guest Pointer Authentication support
- Better discrimination of perf counters between host and guests
Conflicts:
include/uapi/linux/kvm.h
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git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD
PPC KVM update for 5.2
* Support for guests to access the new POWER9 XIVE interrupt controller
hardware directly, reducing interrupt latency and overhead for guests.
* In-kernel implementation of the H_PAGE_INIT hypercall.
* Reduce memory usage of sparsely-populated IOMMU tables.
* Several bug fixes.
Second PPC KVM update for 5.2
* Fix a bug, fix a spelling mistake, remove some useless code.
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The RDPMC-exiting control is dependent on the existence of the RDPMC
instruction itself, i.e. is not tied to the "Architectural Performance
Monitoring" feature. For all intents and purposes, the control exists
on all CPUs with VMX support since RDPMC also exists on all VCPUs with
VMX supported. Per Intel's SDM:
The RDPMC instruction was introduced into the IA-32 Architecture in
the Pentium Pro processor and the Pentium processor with MMX technology.
The earlier Pentium processors have performance-monitoring counters, but
they must be read with the RDMSR instruction.
Because RDPMC-exiting always exists, KVM requires the control and refuses
to load if it's not available. As a result, hiding the PMU from a guest
breaks nested virtualization if the guest attemts to use KVM.
While it's not explicitly stated in the RDPMC pseudocode, the VM-Exit
check for RDPMC-exiting follows standard fault vs. VM-Exit prioritization
for privileged instructions, e.g. occurs after the CPL/CR0.PE/CR4.PCE
checks, but before the counter referenced in ECX is checked for validity.
In other words, the original KVM behavior of injecting a #GP was correct,
and the KVM unit test needs to be adjusted accordingly, e.g. eat the #GP
when the unit test guest (L3 in this case) executes RDPMC without
RDPMC-exiting set in the unit test host (L2).
This reverts commit e51bfdb68725dc052d16241ace40ea3140f938aa.
Fixes: e51bfdb68725 ("KVM: nVMX: Expose RDPMC-exiting only when guest supports PMU")
Reported-by: David Hill <hilld@binarystorm.net>
Cc: Saar Amar <saaramar@microsoft.com>
Cc: Mihai Carabas <mihai.carabas@oracle.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Liran Alon <liran.alon@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Currently KVM sets 5 most significant bits of physical address bits
reported by CPUID (boot_cpu_data.x86_phys_bits) for nonpresent or
reserved bits SPTE to mitigate L1TF attack from guest when using shadow
MMU. However for some particular Intel CPUs the physical address bits
of internal cache is greater than physical address bits reported by
CPUID.
Use the kernel's existing boot_cpu_data.x86_cache_bits to determine the
five most significant bits. Doing so improves KVM's L1TF mitigation in
the unlikely scenario that system RAM overlaps the high order bits of
the "real" physical address space as reported by CPUID. This aligns with
the kernel's warnings regarding L1TF mitigation, e.g. in the above
scenario the kernel won't warn the user about lack of L1TF mitigation
if x86_cache_bits is greater than x86_phys_bits.
Also initialize shadow_nonpresent_or_rsvd_mask explicitly to make it
consistent with other 'shadow_{xxx}_mask', and opportunistically add a
WARN once if KVM's L1TF mitigation cannot be applied on a system that
is marked as being susceptible to L1TF.
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Kai Huang <kai.huang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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If L1 is using an MSR bitmap, unconditionally merge the MSR bitmaps from
L0 and L1 for MSR_{KERNEL,}_{FS,GS}_BASE. KVM unconditionally exposes
MSRs L1. If KVM is also running in L1 then it's highly likely L1 is
also exposing the MSRs to L2, i.e. KVM doesn't need to intercept L2
accesses.
Based on code from Jintack Lim.
Cc: Jintack Lim <jintack@xxxxxxxxxxxxxxx>
Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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There is a spelling mistake in a pr_err message, fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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Commit 70ea13f6e609 ("KVM: PPC: Book3S HV: Flush TLB on secondary radix
threads", 2019-04-29) aimed to make radix guests that are using the
real-mode entry path load the LPID register and flush the TLB in the
same place where those things are done for HPT guests. However, it
omitted to remove a branch which branches around that code for radix
guests. The result is that with indep_thread_mode = N, radix guests
don't run correctly. (With indep_threads_mode = Y, which is the
default, radix guests use a different entry path.)
This removes the offending branch, and also the load and compare that
the branch depends on, since the cr7 setting is now unused.
Reported-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Tested-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Fixes: 70ea13f6e609 ("KVM: PPC: Book3S HV: Flush TLB on secondary radix threads")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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nested_run_pending=1 implies we have successfully entered guest mode.
Move setting from external state in vmx_set_nested_state() until after
all other checks are complete.
Based on a patch by Aaron Lewis.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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new state
Move call to nested_enable_evmcs until after free_nested() is complete.
Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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When a VCPU doesn't have pointer auth, we want to hide all four pointer
auth ID register fields from the guest, not just one of them.
Fixes: 384b40caa8af ("KVM: arm/arm64: Context-switch ptrauth registers")
Reported-by: Andrew Murray <andrew.murray@arm.com>
Fscked-up-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Use specific inline functions for RIP and RSP instead of
going through kvm_register_read and kvm_register_write,
which are quite a mouthful. kvm_rsp_read and kvm_rsp_write
did not exist, so add them.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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... now that there is no overhead when using dedicated accessors.
Opportunistically remove a bogus "FIXME" in handle_rdmsr() regarding
the upper 32 bits of RAX and RDX. Zeroing the upper 32 bits is
architecturally correct as 32-bit writes in 64-bit mode unconditionally
clear the upper 32 bits.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Except for RSP and RIP, which are held in VMX's VMCS, GPRs are always
treated "available and dirtly" on both VMX and SVM, i.e. are
unconditionally loaded/saved immediately before/after VM-Enter/VM-Exit.
Eliminating the unnecessary caching code reduces the size of KVM by a
non-trivial amount, much of which comes from the most common code paths.
E.g. on x86_64, kvm_emulate_cpuid() is reduced from 342 to 182 bytes and
kvm_emulate_hypercall() from 1362 to 1143, with the total size of KVM
dropping by ~1000 bytes. With CONFIG_RETPOLINE=y, the numbers are even
more pronounced, e.g.: 353->182, 1418->1172 and well over 2000 bytes.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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pfn_valid check is not sufficient because it only checks if a page has a struct
page or not, if "mem=" was passed to the kernel some valid pages won't have a
struct page. This means that if guests were assigned valid memory that lies
after the mem= boundary it will be passed uncached to the guest no matter what
the guest caching attributes are for this memory.
Introduce a new function e820__mapped_raw_any which is equivalent to
e820__mapped_any but uses the original e820 unmodified and use it to
identify real *RAM*.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Use page_address_valid in a few more locations that is already checking for
a page aligned address that does not cross the maximum physical address.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Use kvm_vcpu_map for accessing the enlightened VMCS since using
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Use kvm_vcpu_map for accessing the shadow VMCS since using
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzessutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Use the new mapping API for mapping guest memory to avoid depending on
"struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Use kvm_vcpu_map in emulator_cmpxchg_emulated since using
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <kjonrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Use kvm_vcpu_map when mapping the posted interrupt descriptor table since
using kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory
that has a "struct page".
One additional semantic change is that the virtual host mapping lifecycle
has changed a bit. It now has the same lifetime of the pinning of the
interrupt descriptor table page on the host side.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Use kvm_vcpu_map when mapping the virtual APIC page since using
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".
One additional semantic change is that the virtual host mapping lifecycle
has changed a bit. It now has the same lifetime of the pinning of the
virtual APIC page on the host side.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Use kvm_vcpu_map when mapping the L1 MSR bitmap since using
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Use kvm_vcpu_map to the map the VMCS12 from guest memory because
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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cmpxchg_gpte() calls get_user_pages_fast() to retrieve the number of
pages and the respective struct page to map in the kernel virtual
address space.
This doesn't work if get_user_pages_fast() is invoked with a userspace
virtual address that's backed by PFNs outside of kernel reach (e.g., when
limiting the kernel memory with mem= in the command line and using
/dev/mem to map memory).
If get_user_pages_fast() fails, look up the VMA that back the userspace
virtual address, compute the PFN and the physical address, and map it in
the kernel virtual address space with memremap().
Signed-off-by: Filippo Sironi <sironi@amazon.de>
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Update the PML table without mapping and unmapping the page. This also
avoids using kvm_vcpu_gpa_to_page(..) which assumes that there is a "struct
page" for guest memory.
As a side-effect of using kvm_write_guest_page the page is also properly
marked as dirty.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Read the data directly from guest memory instead of the map->read->unmap
sequence. This also avoids using kvm_vcpu_gpa_to_page() and kmap() which
assumes that there is a "struct page" for guest memory.
Suggested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Jim Mattson <jmattson@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The hardware configuration register has some useful bits which can be
used by guests. Implement McStatusWrEn which can be used by guests when
injecting MCEs with the in-kernel mce-inject module.
For that, we need to set bit 18 - McStatusWrEn - first, before writing
the MCi_STATUS registers (otherwise we #GP).
Add the required machinery to do so.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: KVM <kvm@vger.kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yazen Ghannam <Yazen.Ghannam@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The capabilities header depends on asm/vmx.h but doesn't explicitly
include said file. This currently doesn't cause problems as all users
of capbilities.h first include asm/vmx.h, but the issue often results in
build errors if someone starts moving things around the VMX files.
Fixes: 3077c1910882 ("KVM: VMX: Move capabilities structs and helpers to dedicated file")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Smatch complains about this:
arch/x86/kvm/vmx/vmx.c:5730 dump_vmcs()
warn: KERN_* level not at start of string
The code should be using pr_cont() instead of pr_err().
Fixes: 9d609649bb29 ("KVM: vmx: print more APICv fields in dump_vmcs")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Ten percent of nothin' is... let me do the math here. Nothin' into
nothin', carry the nothin'...
Cc: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Checking for a pending non-periodic interrupt in start_hv_timer() leads
to restart_apic_timer() making an unnecessary call to start_sw_timer()
due to start_hv_timer() returning false.
Alternatively, start_hv_timer() could return %true when there is a
pending non-periodic interrupt, but that approach is less intuitive,
i.e. would require a beefy comment to explain an otherwise simple check.
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Suggested-by: Liran Alon <liran.alon@oracle.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Refactor kvm_x86_ops->set_hv_timer to use an explicit parameter for
stating that the timer has expired. Overloading the return value is
unnecessarily clever, e.g. can lead to confusion over the proper return
value from start_hv_timer() when r==1.
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Explicitly call cancel_hv_timer() instead of returning %false to coerce
restart_apic_timer() into canceling it by way of start_sw_timer().
Functionally, the existing code is correct in the sense that it doesn't
doing anything visibily wrong, e.g. generate spurious interrupts or miss
an interrupt. But it's extremely confusing and inefficient, e.g. there
are multiple extraneous calls to apic_timer_expired() that effectively
get dropped due to @timer_pending being %true.
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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...now that VMX's preemption timer, i.e. the hv_timer, also adjusts its
programmed time based on lapic_timer_advance_ns. Without the delay, a
guest can see a timer interrupt arrive before the requested time when
KVM is using the hv_timer to emulate the guest's interrupt.
Fixes: c5ce8235cffa0 ("KVM: VMX: Optimize tscdeadline timer latency")
Cc: <stable@vger.kernel.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Since commits 668fffa3f838 ("kvm: better MWAIT emulation for guestsâ€)
and 4d5422cea3b6 ("KVM: X86: Provide a capability to disable MWAIT interceptsâ€),
KVM was modified to allow an admin to configure certain guests to execute
MONITOR/MWAIT inside guest without being intercepted by host.
This is useful in case admin wishes to allocate a dedicated logical
processor for each vCPU thread. Thus, making it safe for guest to
completely control the power-state of the logical processor.
The ability to use this new KVM capability was introduced to QEMU by
commits 6f131f13e68d ("kvm: support -overcommit cpu-pm=on|offâ€) and
2266d4431132 ("i386/cpu: make -cpu host support monitor/mwaitâ€).
However, exposing MONITOR/MWAIT to a Linux guest may cause it's intel_idle
kernel module to execute c1e_promotion_disable() which will attempt to
RDMSR/WRMSR from/to MSR_IA32_POWER_CTL to manipulate the "C1E Enable"
bit. This behaviour was introduced by commit
32e9518005c8 ("intel_idle: export both C1 and C1Eâ€).
Becuase KVM doesn't emulate this MSR, running KVM with ignore_msrs=0
will cause the above guest behaviour to raise a #GP which will cause
guest to kernel panic.
Therefore, add support for nop emulation of MSR_IA32_POWER_CTL to
avoid #GP in guest in this scenario.
Future commits can optimise emulation further by reflecting guest
MSR changes to host MSR to provide guest with the ability to
fine-tune the dedicated logical processor power-state.
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Let guests clear the Intel PT ToPA PMI status (bit 55 of
MSR_CORE_PERF_GLOBAL_OVF_CTRL).
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Inject a PMI for KVM guest when Intel PT working
in Host-Guest mode and Guest ToPA entry memory buffer
was completely filled.
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
KVM: s390: Features and fixes for 5.2
- VSIE crypto fixes
- new guest features for gen15
- disable halt polling for nested virtualization with overcommit
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This adds code to ensure that after a XIVE or XICS-on-XIVE KVM device
is closed, KVM will not try to enable or disable any of the escalation
interrupts for the VCPUs. We don't have to worry about races between
clearing the pointers and use of the pointers by the XIVE context
push/pull code, because the callers hold the vcpu->mutex, which is
also taken by the KVM_RUN code. Therefore the vcpu cannot be entering
or exiting the guest concurrently.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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Now that we have the possibility of a XIVE or XICS-on-XIVE device being
released while the VM is still running, we need to be careful about
races and potential use-after-free bugs. Although the kvmppc_xive
struct is not freed, but kept around for re-use, the kvmppc_xive_vcpu
structs are freed, and they are used extensively in both the XIVE native
and XICS-on-XIVE code.
There are various ways in which XIVE code gets invoked:
- VCPU entry and exit, which do push and pull operations on the XIVE hardware
- one_reg get and set functions (vcpu->mutex is held)
- XICS hypercalls (but only inside guest execution, not from
kvmppc_pseries_do_hcall)
- device creation calls (kvm->lock is held)
- device callbacks - get/set attribute, mmap, pagefault, release/destroy
- set_mapped/clr_mapped calls (kvm->lock is held)
- connect_vcpu calls
- debugfs file read callbacks
Inside a device release function, we know that userspace cannot have an
open file descriptor referring to the device, nor can it have any mmapped
regions from the device. Therefore the device callbacks are excluded,
as are the connect_vcpu calls (since they need a fd for the device).
Further, since the caller holds the kvm->lock mutex, no other device
creation calls or set/clr_mapped calls can be executing concurrently.
To exclude VCPU execution and XICS hypercalls, we temporarily set
kvm->arch.mmu_ready to 0. This forces any VCPU task that is trying to
enter the guest to take the kvm->lock mutex, which is held by the caller
of the release function. Then, sending an IPI to all other CPUs forces
any VCPU currently executing in the guest to exit.
Finally, we take the vcpu->mutex for each VCPU around the process of
cleaning up and freeing its XIVE data structures, in order to exclude
any one_reg get/set calls.
To exclude the debugfs read callbacks, we just need to ensure that
debugfs_remove is called before freeing any data structures. Once it
returns we know that no CPU can be executing the callbacks (for our
kvmppc_xive instance).
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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When a P9 sPAPR VM boots, the CAS negotiation process determines which
interrupt mode to use (XICS legacy or XIVE native) and invokes a
machine reset to activate the chosen mode.
We introduce 'release' methods for the XICS-on-XIVE and the XIVE
native KVM devices which are called when the file descriptor of the
device is closed after the TIMA and ESB pages have been unmapped.
They perform the necessary cleanups : clear the vCPU interrupt
presenters that could be attached and then destroy the device. The
'release' methods replace the 'destroy' methods as 'destroy' is not
called anymore once 'release' is. Compatibility with older QEMU is
nevertheless maintained.
This is not considered as a safe operation as the vCPUs are still
running and could be referencing the KVM device through their
presenters. To protect the system from any breakage, the kvmppc_xive
objects representing both KVM devices are now stored in an array under
the VM. Allocation is performed on first usage and memory is freed
only when the VM exits.
[paulus@ozlabs.org - Moved freeing of xive structures to book3s.c,
put it under #ifdef CONFIG_KVM_XICS.]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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Full support for the XIVE native exploitation mode is now available,
advertise the capability KVM_CAP_PPC_IRQ_XIVE for guests running on
PowerNV KVM Hypervisors only. Support for nested guests (pseries KVM
Hypervisor) is not yet available. XIVE should also have been activated
which is default setting on POWER9 systems running a recent Linux
kernel.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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The KVM XICS-over-XIVE device and the proposed KVM XIVE native device
implement an IRQ space for the guest using the generic IPI interrupts
of the XIVE IC controller. These interrupts are allocated at the OPAL
level and "mapped" into the guest IRQ number space in the range 0-0x1FFF.
Interrupt management is performed in the XIVE way: using loads and
stores on the addresses of the XIVE IPI interrupt ESB pages.
Both KVM devices share the same internal structure caching information
on the interrupts, among which the xive_irq_data struct containing the
addresses of the IPI ESB pages and an extra one in case of pass-through.
The later contains the addresses of the ESB pages of the underlying HW
controller interrupts, PHB4 in all cases for now.
A guest, when running in the XICS legacy interrupt mode, lets the KVM
XICS-over-XIVE device "handle" interrupt management, that is to
perform the loads and stores on the addresses of the ESB pages of the
guest interrupts. However, when running in XIVE native exploitation
mode, the KVM XIVE native device exposes the interrupt ESB pages to
the guest and lets the guest perform directly the loads and stores.
The VMA exposing the ESB pages make use of a custom VM fault handler
which role is to populate the VMA with appropriate pages. When a fault
occurs, the guest IRQ number is deduced from the offset, and the ESB
pages of associated XIVE IPI interrupt are inserted in the VMA (using
the internal structure caching information on the interrupts).
Supporting device passthrough in the guest running in XIVE native
exploitation mode adds some extra refinements because the ESB pages
of a different HW controller (PHB4) need to be exposed to the guest
along with the initial IPI ESB pages of the XIVE IC controller. But
the overall mechanic is the same.
When the device HW irqs are mapped into or unmapped from the guest
IRQ number space, the passthru_irq helpers, kvmppc_xive_set_mapped()
and kvmppc_xive_clr_mapped(), are called to record or clear the
passthrough interrupt information and to perform the switch.
The approach taken by this patch is to clear the ESB pages of the
guest IRQ number being mapped and let the VM fault handler repopulate.
The handler will insert the ESB page corresponding to the HW interrupt
of the device being passed-through or the initial IPI ESB page if the
device is being removed.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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Each source is associated with an Event State Buffer (ESB) with a
even/odd pair of pages which provides commands to manage the source:
to trigger, to EOI, to turn off the source for instance.
The custom VM fault handler will deduce the guest IRQ number from the
offset of the fault, and the ESB page of the associated XIVE interrupt
will be inserted into the VMA using the internal structure caching
information on the interrupts.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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Each thread has an associated Thread Interrupt Management context
composed of a set of registers. These registers let the thread handle
priority management and interrupt acknowledgment. The most important
are :
- Interrupt Pending Buffer (IPB)
- Current Processor Priority (CPPR)
- Notification Source Register (NSR)
They are exposed to software in four different pages each proposing a
view with a different privilege. The first page is for the physical
thread context and the second for the hypervisor. Only the third
(operating system) and the fourth (user level) are exposed the guest.
A custom VM fault handler will populate the VMA with the appropriate
pages, which should only be the OS page for now.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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The state of the thread interrupt management registers needs to be
collected for migration. These registers are cached under the
'xive_saved_state.w01' field of the VCPU when the VPCU context is
pulled from the HW thread. An OPAL call retrieves the backup of the
IPB register in the underlying XIVE NVT structure and merges it in the
KVM state.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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When migration of a VM is initiated, a first copy of the RAM is
transferred to the destination before the VM is stopped, but there is
no guarantee that the EQ pages in which the event notifications are
queued have not been modified.
To make sure migration will capture a consistent memory state, the
XIVE device should perform a XIVE quiesce sequence to stop the flow of
event notifications and stabilize the EQs. This is the purpose of the
KVM_DEV_XIVE_EQ_SYNC control which will also marks the EQ pages dirty
to force their transfer.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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This control will be used by the H_INT_SYNC hcall from QEMU to flush
event notifications on the XIVE IC owning the source.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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This control is to be used by the H_INT_RESET hcall from QEMU. Its
purpose is to clear all configuration of the sources and EQs. This is
necessary in case of a kexec (for a kdump kernel for instance) to make
sure that no remaining configuration is left from the previous boot
setup so that the new kernel can start safely from a clean state.
The queue 7 is ignored when the XIVE device is configured to run in
single escalation mode. Prio 7 is used by escalations.
The XIVE VP is kept enabled as the vCPU is still active and connected
to the XIVE device.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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These controls will be used by the H_INT_SET_QUEUE_CONFIG and
H_INT_GET_QUEUE_CONFIG hcalls from QEMU to configure the underlying
Event Queue in the XIVE IC. They will also be used to restore the
configuration of the XIVE EQs and to capture the internal run-time
state of the EQs. Both 'get' and 'set' rely on an OPAL call to access
the EQ toggle bit and EQ index which are updated by the XIVE IC when
event notifications are enqueued in the EQ.
The value of the guest physical address of the event queue is saved in
the XIVE internal xive_q structure for later use. That is when
migration needs to mark the EQ pages dirty to capture a consistent
memory state of the VM.
To be noted that H_INT_SET_QUEUE_CONFIG does not require the extra
OPAL call setting the EQ toggle bit and EQ index to configure the EQ,
but restoring the EQ state will.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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