<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/x86/hyperv, branch v6.0</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm</title>
<updated>2022-08-04T21:59:54+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-08-04T21:59:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7c5c3a6177fa9646884114fc7f2e970b0bc50dc9'/>
<id>7c5c3a6177fa9646884114fc7f2e970b0bc50dc9</id>
<content type='text'>
Pull kvm updates from Paolo Bonzini:
 "Quite a large pull request due to a selftest API overhaul and some
  patches that had come in too late for 5.19.

  ARM:

   - Unwinder implementations for both nVHE modes (classic and
     protected), complete with an overflow stack

   - Rework of the sysreg access from userspace, with a complete rewrite
     of the vgic-v3 view to allign with the rest of the infrastructure

   - Disagregation of the vcpu flags in separate sets to better track
     their use model.

   - A fix for the GICv2-on-v3 selftest

   - A small set of cosmetic fixes

  RISC-V:

   - Track ISA extensions used by Guest using bitmap

   - Added system instruction emulation framework

   - Added CSR emulation framework

   - Added gfp_custom flag in struct kvm_mmu_memory_cache

   - Added G-stage ioremap() and iounmap() functions

   - Added support for Svpbmt inside Guest

  s390:

   - add an interface to provide a hypervisor dump for secure guests

   - improve selftests to use TAP interface

   - enable interpretive execution of zPCI instructions (for PCI
     passthrough)

   - First part of deferred teardown

   - CPU Topology

   - PV attestation

   - Minor fixes

  x86:

   - Permit guests to ignore single-bit ECC errors

   - Intel IPI virtualization

   - Allow getting/setting pending triple fault with
     KVM_GET/SET_VCPU_EVENTS

   - PEBS virtualization

   - Simplify PMU emulation by just using PERF_TYPE_RAW events

   - More accurate event reinjection on SVM (avoid retrying
     instructions)

   - Allow getting/setting the state of the speaker port data bit

   - Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls
     are inconsistent

   - "Notify" VM exit (detect microarchitectural hangs) for Intel

   - Use try_cmpxchg64 instead of cmpxchg64

   - Ignore benign host accesses to PMU MSRs when PMU is disabled

   - Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior

   - Allow NX huge page mitigation to be disabled on a per-vm basis

   - Port eager page splitting to shadow MMU as well

   - Enable CMCI capability by default and handle injected UCNA errors

   - Expose pid of vcpu threads in debugfs

   - x2AVIC support for AMD

   - cleanup PIO emulation

   - Fixes for LLDT/LTR emulation

   - Don't require refcounted "struct page" to create huge SPTEs

   - Miscellaneous cleanups:
      - MCE MSR emulation
      - Use separate namespaces for guest PTEs and shadow PTEs bitmasks
      - PIO emulation
      - Reorganize rmap API, mostly around rmap destruction
      - Do not workaround very old KVM bugs for L0 that runs with nesting enabled
      - new selftests API for CPUID

  Generic:

   - Fix races in gfn-&gt;pfn cache refresh; do not pin pages tracked by
     the cache

   - new selftests API using struct kvm_vcpu instead of a (vm, id)
     tuple"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (606 commits)
  selftests: kvm: set rax before vmcall
  selftests: KVM: Add exponent check for boolean stats
  selftests: KVM: Provide descriptive assertions in kvm_binary_stats_test
  selftests: KVM: Check stat name before other fields
  KVM: x86/mmu: remove unused variable
  RISC-V: KVM: Add support for Svpbmt inside Guest/VM
  RISC-V: KVM: Use PAGE_KERNEL_IO in kvm_riscv_gstage_ioremap()
  RISC-V: KVM: Add G-stage ioremap() and iounmap() functions
  KVM: Add gfp_custom flag in struct kvm_mmu_memory_cache
  RISC-V: KVM: Add extensible CSR emulation framework
  RISC-V: KVM: Add extensible system instruction emulation framework
  RISC-V: KVM: Factor-out instruction emulation into separate sources
  RISC-V: KVM: move preempt_disable() call in kvm_arch_vcpu_ioctl_run
  RISC-V: KVM: Make kvm_riscv_guest_timer_init a void function
  RISC-V: KVM: Fix variable spelling mistake
  RISC-V: KVM: Improve ISA extension by using a bitmap
  KVM, x86/mmu: Fix the comment around kvm_tdp_mmu_zap_leafs()
  KVM: SVM: Dump Virtual Machine Save Area (VMSA) to klog
  KVM: x86/mmu: Treat NX as a valid SPTE bit for NPT
  KVM: x86: Do not block APIC write for non ICR registers
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull kvm updates from Paolo Bonzini:
 "Quite a large pull request due to a selftest API overhaul and some
  patches that had come in too late for 5.19.

  ARM:

   - Unwinder implementations for both nVHE modes (classic and
     protected), complete with an overflow stack

   - Rework of the sysreg access from userspace, with a complete rewrite
     of the vgic-v3 view to allign with the rest of the infrastructure

   - Disagregation of the vcpu flags in separate sets to better track
     their use model.

   - A fix for the GICv2-on-v3 selftest

   - A small set of cosmetic fixes

  RISC-V:

   - Track ISA extensions used by Guest using bitmap

   - Added system instruction emulation framework

   - Added CSR emulation framework

   - Added gfp_custom flag in struct kvm_mmu_memory_cache

   - Added G-stage ioremap() and iounmap() functions

   - Added support for Svpbmt inside Guest

  s390:

   - add an interface to provide a hypervisor dump for secure guests

   - improve selftests to use TAP interface

   - enable interpretive execution of zPCI instructions (for PCI
     passthrough)

   - First part of deferred teardown

   - CPU Topology

   - PV attestation

   - Minor fixes

  x86:

   - Permit guests to ignore single-bit ECC errors

   - Intel IPI virtualization

   - Allow getting/setting pending triple fault with
     KVM_GET/SET_VCPU_EVENTS

   - PEBS virtualization

   - Simplify PMU emulation by just using PERF_TYPE_RAW events

   - More accurate event reinjection on SVM (avoid retrying
     instructions)

   - Allow getting/setting the state of the speaker port data bit

   - Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls
     are inconsistent

   - "Notify" VM exit (detect microarchitectural hangs) for Intel

   - Use try_cmpxchg64 instead of cmpxchg64

   - Ignore benign host accesses to PMU MSRs when PMU is disabled

   - Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior

   - Allow NX huge page mitigation to be disabled on a per-vm basis

   - Port eager page splitting to shadow MMU as well

   - Enable CMCI capability by default and handle injected UCNA errors

   - Expose pid of vcpu threads in debugfs

   - x2AVIC support for AMD

   - cleanup PIO emulation

   - Fixes for LLDT/LTR emulation

   - Don't require refcounted "struct page" to create huge SPTEs

   - Miscellaneous cleanups:
      - MCE MSR emulation
      - Use separate namespaces for guest PTEs and shadow PTEs bitmasks
      - PIO emulation
      - Reorganize rmap API, mostly around rmap destruction
      - Do not workaround very old KVM bugs for L0 that runs with nesting enabled
      - new selftests API for CPUID

  Generic:

   - Fix races in gfn-&gt;pfn cache refresh; do not pin pages tracked by
     the cache

   - new selftests API using struct kvm_vcpu instead of a (vm, id)
     tuple"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (606 commits)
  selftests: kvm: set rax before vmcall
  selftests: KVM: Add exponent check for boolean stats
  selftests: KVM: Provide descriptive assertions in kvm_binary_stats_test
  selftests: KVM: Check stat name before other fields
  KVM: x86/mmu: remove unused variable
  RISC-V: KVM: Add support for Svpbmt inside Guest/VM
  RISC-V: KVM: Use PAGE_KERNEL_IO in kvm_riscv_gstage_ioremap()
  RISC-V: KVM: Add G-stage ioremap() and iounmap() functions
  KVM: Add gfp_custom flag in struct kvm_mmu_memory_cache
  RISC-V: KVM: Add extensible CSR emulation framework
  RISC-V: KVM: Add extensible system instruction emulation framework
  RISC-V: KVM: Factor-out instruction emulation into separate sources
  RISC-V: KVM: move preempt_disable() call in kvm_arch_vcpu_ioctl_run
  RISC-V: KVM: Make kvm_riscv_guest_timer_init a void function
  RISC-V: KVM: Fix variable spelling mistake
  RISC-V: KVM: Improve ISA extension by using a bitmap
  KVM, x86/mmu: Fix the comment around kvm_tdp_mmu_zap_leafs()
  KVM: SVM: Dump Virtual Machine Save Area (VMSA) to klog
  KVM: x86/mmu: Treat NX as a valid SPTE bit for NPT
  KVM: x86: Do not block APIC write for non ICR registers
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge remote-tracking branch 'kvm/next' into kvm-next-5.20</title>
<updated>2022-08-01T07:21:00+00:00</updated>
<author>
<name>Paolo Bonzini</name>
<email>pbonzini@redhat.com</email>
</author>
<published>2022-07-29T13:46:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=63f4b210414b65aa3103c54369cacbd0b1bdf02f'/>
<id>63f4b210414b65aa3103c54369cacbd0b1bdf02f</id>
<content type='text'>
KVM/s390, KVM/x86 and common infrastructure changes for 5.20

x86:

* Permit guests to ignore single-bit ECC errors

* Fix races in gfn-&gt;pfn cache refresh; do not pin pages tracked by the cache

* Intel IPI virtualization

* Allow getting/setting pending triple fault with KVM_GET/SET_VCPU_EVENTS

* PEBS virtualization

* Simplify PMU emulation by just using PERF_TYPE_RAW events

* More accurate event reinjection on SVM (avoid retrying instructions)

* Allow getting/setting the state of the speaker port data bit

* Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls are inconsistent

* "Notify" VM exit (detect microarchitectural hangs) for Intel

* Cleanups for MCE MSR emulation

s390:

* add an interface to provide a hypervisor dump for secure guests

* improve selftests to use TAP interface

* enable interpretive execution of zPCI instructions (for PCI passthrough)

* First part of deferred teardown

* CPU Topology

* PV attestation

* Minor fixes

Generic:

* new selftests API using struct kvm_vcpu instead of a (vm, id) tuple

x86:

* Use try_cmpxchg64 instead of cmpxchg64

* Bugfixes

* Ignore benign host accesses to PMU MSRs when PMU is disabled

* Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior

* x86/MMU: Allow NX huge pages to be disabled on a per-vm basis

* Port eager page splitting to shadow MMU as well

* Enable CMCI capability by default and handle injected UCNA errors

* Expose pid of vcpu threads in debugfs

* x2AVIC support for AMD

* cleanup PIO emulation

* Fixes for LLDT/LTR emulation

* Don't require refcounted "struct page" to create huge SPTEs

x86 cleanups:

* Use separate namespaces for guest PTEs and shadow PTEs bitmasks

* PIO emulation

* Reorganize rmap API, mostly around rmap destruction

* Do not workaround very old KVM bugs for L0 that runs with nesting enabled

* new selftests API for CPUID
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
KVM/s390, KVM/x86 and common infrastructure changes for 5.20

x86:

* Permit guests to ignore single-bit ECC errors

* Fix races in gfn-&gt;pfn cache refresh; do not pin pages tracked by the cache

* Intel IPI virtualization

* Allow getting/setting pending triple fault with KVM_GET/SET_VCPU_EVENTS

* PEBS virtualization

* Simplify PMU emulation by just using PERF_TYPE_RAW events

* More accurate event reinjection on SVM (avoid retrying instructions)

* Allow getting/setting the state of the speaker port data bit

* Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls are inconsistent

* "Notify" VM exit (detect microarchitectural hangs) for Intel

* Cleanups for MCE MSR emulation

s390:

* add an interface to provide a hypervisor dump for secure guests

* improve selftests to use TAP interface

* enable interpretive execution of zPCI instructions (for PCI passthrough)

* First part of deferred teardown

* CPU Topology

* PV attestation

* Minor fixes

Generic:

* new selftests API using struct kvm_vcpu instead of a (vm, id) tuple

x86:

* Use try_cmpxchg64 instead of cmpxchg64

* Bugfixes

* Ignore benign host accesses to PMU MSRs when PMU is disabled

* Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior

* x86/MMU: Allow NX huge pages to be disabled on a per-vm basis

* Port eager page splitting to shadow MMU as well

* Enable CMCI capability by default and handle injected UCNA errors

* Expose pid of vcpu threads in debugfs

* x2AVIC support for AMD

* cleanup PIO emulation

* Fixes for LLDT/LTR emulation

* Don't require refcounted "struct page" to create huge SPTEs

x86 cleanups:

* Use separate namespaces for guest PTEs and shadow PTEs bitmasks

* PIO emulation

* Reorganize rmap API, mostly around rmap destruction

* Do not workaround very old KVM bugs for L0 that runs with nesting enabled

* new selftests API for CPUID
</pre>
</div>
</content>
</entry>
<entry>
<title>genirq: Return a const cpumask from irq_data_get_affinity_mask</title>
<updated>2022-07-07T08:38:04+00:00</updated>
<author>
<name>Samuel Holland</name>
<email>samuel@sholland.org</email>
</author>
<published>2022-07-01T20:00:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4d0b8298818b623f5fa51d5c49e1a142d3618ac9'/>
<id>4d0b8298818b623f5fa51d5c49e1a142d3618ac9</id>
<content type='text'>
Now that the irq_data_update_affinity helper exists, enforce its use
by returning a a const cpumask from irq_data_get_affinity_mask.

Since the previous commit already updated places that needed to call
irq_data_update_affinity, this commit updates the remaining code that
either did not modify the cpumask or immediately passed the modified
mask to irq_set_affinity.

Signed-off-by: Samuel Holland &lt;samuel@sholland.org&gt;
Reviewed-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Signed-off-by: Marc Zyngier &lt;maz@kernel.org&gt;
Link: https://lore.kernel.org/r/20220701200056.46555-8-samuel@sholland.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Now that the irq_data_update_affinity helper exists, enforce its use
by returning a a const cpumask from irq_data_get_affinity_mask.

Since the previous commit already updated places that needed to call
irq_data_update_affinity, this commit updates the remaining code that
either did not modify the cpumask or immediately passed the modified
mask to irq_set_affinity.

Signed-off-by: Samuel Holland &lt;samuel@sholland.org&gt;
Reviewed-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Signed-off-by: Marc Zyngier &lt;maz@kernel.org&gt;
Link: https://lore.kernel.org/r/20220701200056.46555-8-samuel@sholland.org
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: x86: lapic: Rename [GET/SET]_APIC_DEST_FIELD to [GET/SET]_XAPIC_DEST_FIELD</title>
<updated>2022-06-24T16:44:34+00:00</updated>
<author>
<name>Suravee Suthikulpanit</name>
<email>suravee.suthikulpanit@amd.com</email>
</author>
<published>2022-05-19T10:26:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=bf348f667ed36c0799dd6d10adb7be9cdfea48c3'/>
<id>bf348f667ed36c0799dd6d10adb7be9cdfea48c3</id>
<content type='text'>
To signify that the macros only support 8-bit xAPIC destination ID.

Suggested-by: Maxim Levitsky &lt;mlevitsk@redhat.com&gt;
Reviewed-by: Maxim Levitsky &lt;mlevitsk@redhat.com&gt;
Reviewed-by: Pankaj Gupta &lt;pankaj.gupta@amd.com&gt;
Signed-off-by: Suravee Suthikulpanit &lt;suravee.suthikulpanit@amd.com&gt;
Reviewed-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Message-Id: &lt;20220519102709.24125-3-suravee.suthikulpanit@amd.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To signify that the macros only support 8-bit xAPIC destination ID.

Suggested-by: Maxim Levitsky &lt;mlevitsk@redhat.com&gt;
Reviewed-by: Maxim Levitsky &lt;mlevitsk@redhat.com&gt;
Reviewed-by: Pankaj Gupta &lt;pankaj.gupta@amd.com&gt;
Signed-off-by: Suravee Suthikulpanit &lt;suravee.suthikulpanit@amd.com&gt;
Reviewed-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Message-Id: &lt;20220519102709.24125-3-suravee.suthikulpanit@amd.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/Hyper-V: Add SEV negotiate protocol support in Isolation VM</title>
<updated>2022-06-15T18:27:40+00:00</updated>
<author>
<name>Tianyu Lan</name>
<email>Tianyu.Lan@microsoft.com</email>
</author>
<published>2022-06-14T01:45:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=49d6a3c062a1026a5ba957c46f3603c372288ab6'/>
<id>49d6a3c062a1026a5ba957c46f3603c372288ab6</id>
<content type='text'>
Hyper-V Isolation VM current code uses sev_es_ghcb_hv_call()
to read/write MSR via GHCB page and depends on the sev code.
This may cause regression when sev code changes interface
design.

The latest SEV-ES code requires to negotiate GHCB version before
reading/writing MSR via GHCB page and sev_es_ghcb_hv_call() doesn't
work for Hyper-V Isolation VM. Add Hyper-V ghcb related implementation
to decouple SEV and Hyper-V code. Negotiate GHCB version in the
hyperv_init() and use the version to communicate with Hyper-V
in the ghcb hv call function.

Fixes: 2ea29c5abbc2 ("x86/sev: Save the negotiated GHCB version")
Signed-off-by: Tianyu Lan &lt;Tianyu.Lan@microsoft.com&gt;
Reviewed-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Link: https://lore.kernel.org/r/20220614014553.1915929-1-ltykernel@gmail.com
Signed-off-by: Wei Liu &lt;wei.liu@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Hyper-V Isolation VM current code uses sev_es_ghcb_hv_call()
to read/write MSR via GHCB page and depends on the sev code.
This may cause regression when sev code changes interface
design.

The latest SEV-ES code requires to negotiate GHCB version before
reading/writing MSR via GHCB page and sev_es_ghcb_hv_call() doesn't
work for Hyper-V Isolation VM. Add Hyper-V ghcb related implementation
to decouple SEV and Hyper-V code. Negotiate GHCB version in the
hyperv_init() and use the version to communicate with Hyper-V
in the ghcb hv call function.

Fixes: 2ea29c5abbc2 ("x86/sev: Save the negotiated GHCB version")
Signed-off-by: Tianyu Lan &lt;Tianyu.Lan@microsoft.com&gt;
Reviewed-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Link: https://lore.kernel.org/r/20220614014553.1915929-1-ltykernel@gmail.com
Signed-off-by: Wei Liu &lt;wei.liu@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'hyperv-next-signed-20220114' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux</title>
<updated>2022-01-16T13:53:00+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-01-16T13:53:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=cb3f09f9afe5286c0aed7a1c5cc71495de166efb'/>
<id>cb3f09f9afe5286c0aed7a1c5cc71495de166efb</id>
<content type='text'>
Pull hyperv updates from Wei Liu:

 - More patches for Hyper-V isolation VM support (Tianyu Lan)

 - Bug fixes and clean-up patches from various people

* tag 'hyperv-next-signed-20220114' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  scsi: storvsc: Fix storvsc_queuecommand() memory leak
  x86/hyperv: Properly deal with empty cpumasks in hyperv_flush_tlb_multi()
  Drivers: hv: vmbus: Initialize request offers message for Isolation VM
  scsi: storvsc: Fix unsigned comparison to zero
  swiotlb: Add CONFIG_HAS_IOMEM check around swiotlb_mem_remap()
  x86/hyperv: Fix definition of hv_ghcb_pg variable
  Drivers: hv: Fix definition of hypercall input &amp; output arg variables
  net: netvsc: Add Isolation VM support for netvsc driver
  scsi: storvsc: Add Isolation VM support for storvsc driver
  hyper-v: Enable swiotlb bounce buffer for Isolation VM
  x86/hyper-v: Add hyperv Isolation VM check in the cc_platform_has()
  swiotlb: Add swiotlb bounce buffer remap function for HV IVM
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull hyperv updates from Wei Liu:

 - More patches for Hyper-V isolation VM support (Tianyu Lan)

 - Bug fixes and clean-up patches from various people

* tag 'hyperv-next-signed-20220114' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  scsi: storvsc: Fix storvsc_queuecommand() memory leak
  x86/hyperv: Properly deal with empty cpumasks in hyperv_flush_tlb_multi()
  Drivers: hv: vmbus: Initialize request offers message for Isolation VM
  scsi: storvsc: Fix unsigned comparison to zero
  swiotlb: Add CONFIG_HAS_IOMEM check around swiotlb_mem_remap()
  x86/hyperv: Fix definition of hv_ghcb_pg variable
  Drivers: hv: Fix definition of hypercall input &amp; output arg variables
  net: netvsc: Add Isolation VM support for netvsc driver
  scsi: storvsc: Add Isolation VM support for storvsc driver
  hyper-v: Enable swiotlb bounce buffer for Isolation VM
  x86/hyper-v: Add hyperv Isolation VM check in the cc_platform_has()
  swiotlb: Add swiotlb bounce buffer remap function for HV IVM
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/hyperv: Properly deal with empty cpumasks in hyperv_flush_tlb_multi()</title>
<updated>2022-01-10T11:50:20+00:00</updated>
<author>
<name>Vitaly Kuznetsov</name>
<email>vkuznets@redhat.com</email>
</author>
<published>2022-01-06T09:46:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=51500b71d500f251037ed339047a4d9e7d7e295b'/>
<id>51500b71d500f251037ed339047a4d9e7d7e295b</id>
<content type='text'>
KASAN detected the following issue:

 BUG: KASAN: slab-out-of-bounds in hyperv_flush_tlb_multi+0xf88/0x1060
 Read of size 4 at addr ffff8880011ccbc0 by task kcompactd0/33

 CPU: 1 PID: 33 Comm: kcompactd0 Not tainted 5.14.0-39.el9.x86_64+debug #1
 Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine,
     BIOS Hyper-V UEFI Release v4.0 12/17/2019
 Call Trace:
  dump_stack_lvl+0x57/0x7d
  print_address_description.constprop.0+0x1f/0x140
  ? hyperv_flush_tlb_multi+0xf88/0x1060
  __kasan_report.cold+0x7f/0x11e
  ? hyperv_flush_tlb_multi+0xf88/0x1060
  kasan_report+0x38/0x50
  hyperv_flush_tlb_multi+0xf88/0x1060
  flush_tlb_mm_range+0x1b1/0x200
  ptep_clear_flush+0x10e/0x150
...
 Allocated by task 0:
  kasan_save_stack+0x1b/0x40
  __kasan_kmalloc+0x7c/0x90
  hv_common_init+0xae/0x115
  hyperv_init+0x97/0x501
  apic_intr_mode_init+0xb3/0x1e0
  x86_late_time_init+0x92/0xa2
  start_kernel+0x338/0x3eb
  secondary_startup_64_no_verify+0xc2/0xcb

 The buggy address belongs to the object at ffff8880011cc800
  which belongs to the cache kmalloc-1k of size 1024
 The buggy address is located 960 bytes inside of
  1024-byte region [ffff8880011cc800, ffff8880011ccc00)

'hyperv_flush_tlb_multi+0xf88/0x1060' points to
hv_cpu_number_to_vp_number() and '960 bytes' means we're trying to get
VP_INDEX for CPU#240. 'nr_cpus' here is exactly 240 so we're trying to
access past hv_vp_index's last element. This can (and will) happen
when 'cpus' mask is empty and cpumask_last() will return '&gt;=nr_cpus'.

Commit ad0a6bad4475 ("x86/hyperv: check cpu mask after interrupt has
been disabled") tried to deal with empty cpumask situation but
apparently didn't fully fix the issue.

'cpus' cpumask which is passed to hyperv_flush_tlb_multi() is
'mm_cpumask(mm)' (which is '&amp;mm-&gt;cpu_bitmap'). This mask changes every
time the particular mm is scheduled/unscheduled on some CPU (see
switch_mm_irqs_off()), disabling IRQs on the CPU which is performing remote
TLB flush has zero influence on whether the particular process can get
scheduled/unscheduled on _other_ CPUs so e.g. in the case where the mm was
scheduled on one other CPU and got unscheduled during
hyperv_flush_tlb_multi()'s execution will lead to cpumask becoming empty.

It doesn't seem that there's a good way to protect 'mm_cpumask(mm)'
from changing during hyperv_flush_tlb_multi()'s execution. It would be
possible to copy it in the very beginning of the function but this is a
waste. It seems we can deal with changing cpumask just fine.

When 'cpus' cpumask changes during hyperv_flush_tlb_multi()'s
execution, there are two possible issues:
- 'Under-flushing': we will not flush TLB on a CPU which got added to
the mask while hyperv_flush_tlb_multi() was already running. This is
not a problem as this is equal to mm getting scheduled on that CPU
right after TLB flush.
- 'Over-flushing': we may flush TLB on a CPU which is already cleared
from the mask. First, extra TLB flush preserves correctness. Second,
Hyper-V's TLB flush hypercall takes 'mm-&gt;pgd' argument so Hyper-V may
avoid the flush if CR3 doesn't match.

Fix the immediate issue with cpumask_last()/hv_cpu_number_to_vp_number()
and remove the pointless cpumask_empty() check from the beginning of the
function as it really doesn't protect anything. Also, avoid the hypercall
altogether when 'flush-&gt;processor_mask' ends up being empty.

Fixes: ad0a6bad4475 ("x86/hyperv: check cpu mask after interrupt has been disabled")
Signed-off-by: Vitaly Kuznetsov &lt;vkuznets@redhat.com&gt;
Reviewed-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Link: https://lore.kernel.org/r/20220106094611.1404218-1-vkuznets@redhat.com
Signed-off-by: Wei Liu &lt;wei.liu@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
KASAN detected the following issue:

 BUG: KASAN: slab-out-of-bounds in hyperv_flush_tlb_multi+0xf88/0x1060
 Read of size 4 at addr ffff8880011ccbc0 by task kcompactd0/33

 CPU: 1 PID: 33 Comm: kcompactd0 Not tainted 5.14.0-39.el9.x86_64+debug #1
 Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine,
     BIOS Hyper-V UEFI Release v4.0 12/17/2019
 Call Trace:
  dump_stack_lvl+0x57/0x7d
  print_address_description.constprop.0+0x1f/0x140
  ? hyperv_flush_tlb_multi+0xf88/0x1060
  __kasan_report.cold+0x7f/0x11e
  ? hyperv_flush_tlb_multi+0xf88/0x1060
  kasan_report+0x38/0x50
  hyperv_flush_tlb_multi+0xf88/0x1060
  flush_tlb_mm_range+0x1b1/0x200
  ptep_clear_flush+0x10e/0x150
...
 Allocated by task 0:
  kasan_save_stack+0x1b/0x40
  __kasan_kmalloc+0x7c/0x90
  hv_common_init+0xae/0x115
  hyperv_init+0x97/0x501
  apic_intr_mode_init+0xb3/0x1e0
  x86_late_time_init+0x92/0xa2
  start_kernel+0x338/0x3eb
  secondary_startup_64_no_verify+0xc2/0xcb

 The buggy address belongs to the object at ffff8880011cc800
  which belongs to the cache kmalloc-1k of size 1024
 The buggy address is located 960 bytes inside of
  1024-byte region [ffff8880011cc800, ffff8880011ccc00)

'hyperv_flush_tlb_multi+0xf88/0x1060' points to
hv_cpu_number_to_vp_number() and '960 bytes' means we're trying to get
VP_INDEX for CPU#240. 'nr_cpus' here is exactly 240 so we're trying to
access past hv_vp_index's last element. This can (and will) happen
when 'cpus' mask is empty and cpumask_last() will return '&gt;=nr_cpus'.

Commit ad0a6bad4475 ("x86/hyperv: check cpu mask after interrupt has
been disabled") tried to deal with empty cpumask situation but
apparently didn't fully fix the issue.

'cpus' cpumask which is passed to hyperv_flush_tlb_multi() is
'mm_cpumask(mm)' (which is '&amp;mm-&gt;cpu_bitmap'). This mask changes every
time the particular mm is scheduled/unscheduled on some CPU (see
switch_mm_irqs_off()), disabling IRQs on the CPU which is performing remote
TLB flush has zero influence on whether the particular process can get
scheduled/unscheduled on _other_ CPUs so e.g. in the case where the mm was
scheduled on one other CPU and got unscheduled during
hyperv_flush_tlb_multi()'s execution will lead to cpumask becoming empty.

It doesn't seem that there's a good way to protect 'mm_cpumask(mm)'
from changing during hyperv_flush_tlb_multi()'s execution. It would be
possible to copy it in the very beginning of the function but this is a
waste. It seems we can deal with changing cpumask just fine.

When 'cpus' cpumask changes during hyperv_flush_tlb_multi()'s
execution, there are two possible issues:
- 'Under-flushing': we will not flush TLB on a CPU which got added to
the mask while hyperv_flush_tlb_multi() was already running. This is
not a problem as this is equal to mm getting scheduled on that CPU
right after TLB flush.
- 'Over-flushing': we may flush TLB on a CPU which is already cleared
from the mask. First, extra TLB flush preserves correctness. Second,
Hyper-V's TLB flush hypercall takes 'mm-&gt;pgd' argument so Hyper-V may
avoid the flush if CR3 doesn't match.

Fix the immediate issue with cpumask_last()/hv_cpu_number_to_vp_number()
and remove the pointless cpumask_empty() check from the beginning of the
function as it really doesn't protect anything. Also, avoid the hypercall
altogether when 'flush-&gt;processor_mask' ends up being empty.

Fixes: ad0a6bad4475 ("x86/hyperv: check cpu mask after interrupt has been disabled")
Signed-off-by: Vitaly Kuznetsov &lt;vkuznets@redhat.com&gt;
Reviewed-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Link: https://lore.kernel.org/r/20220106094611.1404218-1-vkuznets@redhat.com
Signed-off-by: Wei Liu &lt;wei.liu@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/hyperv: Fix definition of hv_ghcb_pg variable</title>
<updated>2021-12-28T14:18:47+00:00</updated>
<author>
<name>Michael Kelley</name>
<email>mikelley@microsoft.com</email>
</author>
<published>2021-12-28T03:31:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e1878402ab2dca12d1426f2fea39757943f3332c'/>
<id>e1878402ab2dca12d1426f2fea39757943f3332c</id>
<content type='text'>
The percpu variable hv_ghcb_pg is incorrectly defined.  The __percpu
qualifier should be associated with the union hv_ghcb * (i.e.,
a pointer), not with the target of the pointer. This distinction
makes no difference to gcc and the generated code, but sparse
correctly complains.  Fix the definition in the interest of
general correctness in addition to making sparse happy.

No functional change.

Fixes: 0cc4f6d9f0b9 ("x86/hyperv: Initialize GHCB page in Isolation VM")
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Link: https://lore.kernel.org/r/1640662315-22260-2-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu &lt;wei.liu@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The percpu variable hv_ghcb_pg is incorrectly defined.  The __percpu
qualifier should be associated with the union hv_ghcb * (i.e.,
a pointer), not with the target of the pointer. This distinction
makes no difference to gcc and the generated code, but sparse
correctly complains.  Fix the definition in the interest of
general correctness in addition to making sparse happy.

No functional change.

Fixes: 0cc4f6d9f0b9 ("x86/hyperv: Initialize GHCB page in Isolation VM")
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Link: https://lore.kernel.org/r/1640662315-22260-2-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu &lt;wei.liu@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: netvsc: Add Isolation VM support for netvsc driver</title>
<updated>2021-12-20T18:01:09+00:00</updated>
<author>
<name>Tianyu Lan</name>
<email>Tianyu.Lan@microsoft.com</email>
</author>
<published>2021-12-13T07:14:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=846da38de0e8224f2f94b885125cf1fd2d7b0d39'/>
<id>846da38de0e8224f2f94b885125cf1fd2d7b0d39</id>
<content type='text'>
In Isolation VM, all shared memory with host needs to mark visible
to host via hvcall. vmbus_establish_gpadl() has already done it for
netvsc rx/tx ring buffer. The page buffer used by vmbus_sendpacket_
pagebuffer() stills need to be handled. Use DMA API to map/umap
these memory during sending/receiving packet and Hyper-V swiotlb
bounce buffer dma address will be returned. The swiotlb bounce buffer
has been masked to be visible to host during boot up.

rx/tx ring buffer is allocated via vzalloc() and they need to be
mapped into unencrypted address space(above vTOM) before sharing
with host and accessing. Add hv_map/unmap_memory() to map/umap rx
/tx ring buffer.

Signed-off-by: Tianyu Lan &lt;Tianyu.Lan@microsoft.com&gt;
Reviewed-by: Haiyang Zhang &lt;haiyangz@microsoft.com&gt;
Reviewed-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Link: https://lore.kernel.org/r/20211213071407.314309-6-ltykernel@gmail.com
Signed-off-by: Wei Liu &lt;wei.liu@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In Isolation VM, all shared memory with host needs to mark visible
to host via hvcall. vmbus_establish_gpadl() has already done it for
netvsc rx/tx ring buffer. The page buffer used by vmbus_sendpacket_
pagebuffer() stills need to be handled. Use DMA API to map/umap
these memory during sending/receiving packet and Hyper-V swiotlb
bounce buffer dma address will be returned. The swiotlb bounce buffer
has been masked to be visible to host during boot up.

rx/tx ring buffer is allocated via vzalloc() and they need to be
mapped into unencrypted address space(above vTOM) before sharing
with host and accessing. Add hv_map/unmap_memory() to map/umap rx
/tx ring buffer.

Signed-off-by: Tianyu Lan &lt;Tianyu.Lan@microsoft.com&gt;
Reviewed-by: Haiyang Zhang &lt;haiyangz@microsoft.com&gt;
Reviewed-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Link: https://lore.kernel.org/r/20211213071407.314309-6-ltykernel@gmail.com
Signed-off-by: Wei Liu &lt;wei.liu@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>hyper-v: Enable swiotlb bounce buffer for Isolation VM</title>
<updated>2021-12-20T18:01:09+00:00</updated>
<author>
<name>Tianyu Lan</name>
<email>Tianyu.Lan@microsoft.com</email>
</author>
<published>2021-12-13T07:14:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=062a5c4260cdb734a4727230c58e38accf413315'/>
<id>062a5c4260cdb734a4727230c58e38accf413315</id>
<content type='text'>
hyperv Isolation VM requires bounce buffer support to copy
data from/to encrypted memory and so enable swiotlb force
mode to use swiotlb bounce buffer for DMA transaction.

In Isolation VM with AMD SEV, the bounce buffer needs to be
accessed via extra address space which is above shared_gpa_boundary
(E.G 39 bit address line) reported by Hyper-V CPUID ISOLATION_CONFIG.
The access physical address will be original physical address +
shared_gpa_boundary. The shared_gpa_boundary in the AMD SEV SNP
spec is called virtual top of memory(vTOM). Memory addresses below
vTOM are automatically treated as private while memory above
vTOM is treated as shared.

Swiotlb bounce buffer code calls set_memory_decrypted()
to mark bounce buffer visible to host and map it in extra
address space via memremap. Populate the shared_gpa_boundary
(vTOM) via swiotlb_unencrypted_base variable.

The map function memremap() can't work in the early place
(e.g ms_hyperv_init_platform()) and so call swiotlb_update_mem_
attributes() in the hyperv_init().

Signed-off-by: Tianyu Lan &lt;Tianyu.Lan@microsoft.com&gt;
Reviewed-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Link: https://lore.kernel.org/r/20211213071407.314309-4-ltykernel@gmail.com
Signed-off-by: Wei Liu &lt;wei.liu@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
hyperv Isolation VM requires bounce buffer support to copy
data from/to encrypted memory and so enable swiotlb force
mode to use swiotlb bounce buffer for DMA transaction.

In Isolation VM with AMD SEV, the bounce buffer needs to be
accessed via extra address space which is above shared_gpa_boundary
(E.G 39 bit address line) reported by Hyper-V CPUID ISOLATION_CONFIG.
The access physical address will be original physical address +
shared_gpa_boundary. The shared_gpa_boundary in the AMD SEV SNP
spec is called virtual top of memory(vTOM). Memory addresses below
vTOM are automatically treated as private while memory above
vTOM is treated as shared.

Swiotlb bounce buffer code calls set_memory_decrypted()
to mark bounce buffer visible to host and map it in extra
address space via memremap. Populate the shared_gpa_boundary
(vTOM) via swiotlb_unencrypted_base variable.

The map function memremap() can't work in the early place
(e.g ms_hyperv_init_platform()) and so call swiotlb_update_mem_
attributes() in the hyperv_init().

Signed-off-by: Tianyu Lan &lt;Tianyu.Lan@microsoft.com&gt;
Reviewed-by: Michael Kelley &lt;mikelley@microsoft.com&gt;
Link: https://lore.kernel.org/r/20211213071407.314309-4-ltykernel@gmail.com
Signed-off-by: Wei Liu &lt;wei.liu@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
