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* Re: [PATCH v7 16/18] KVM: x86: Add guest support for detecting and enabling SEV Live Migration feature.
@ 2020-05-01 13:39 kbuild test robot
  0 siblings, 0 replies; 4+ messages in thread
From: kbuild test robot @ 2020-05-01 13:39 UTC (permalink / raw)
  To: kbuild

[-- Attachment #1: Type: text/plain, Size: 5314 bytes --]

CC: kbuild-all(a)lists.01.org
In-Reply-To: <42947fc3dc7a01c73677560c84dfd87498d381e0.1588234824.git.ashish.kalra@amd.com>
References: <42947fc3dc7a01c73677560c84dfd87498d381e0.1588234824.git.ashish.kalra@amd.com>
TO: Ashish Kalra <Ashish.Kalra@amd.com>
TO: pbonzini(a)redhat.com
CC: tglx(a)linutronix.de
CC: mingo(a)redhat.com
CC: hpa(a)zytor.com
CC: joro(a)8bytes.org
CC: bp(a)suse.de
CC: thomas.lendacky(a)amd.com
CC: x86(a)kernel.org
CC: kvm(a)vger.kernel.org
CC: linux-kernel(a)vger.kernel.org

Hi Ashish,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on v5.7-rc3]
[cannot apply to kvm/linux-next tip/x86/mm tip/x86/core next-20200501]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Ashish-Kalra/Add-AMD-SEV-guest-live-migration-support/20200430-202702
base:    6a8b55ed4056ea5559ebe4f6a4b247f627870d4c
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.1-191-gc51a0382-dirty
        make ARCH=x86_64 allmodconfig
        make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__'
:::::: branch date: 25 hours ago
:::::: commit date: 25 hours ago

If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>


sparse warnings: (new ones prefixed by >>)

>> arch/x86/kernel/kvm.c:410:56: sparse: sparse: invalid initializer
   arch/x86/kernel/kvm.c:795:6: sparse: sparse: symbol 'kvm_sev_migration_hcall' was not declared. Should it be static?

# https://github.com/0day-ci/linux/commit/ec31b001157e1122024857a2b8ffcb9c730e165d
git remote add linux-review https://github.com/0day-ci/linux
git remote update linux-review
git checkout ec31b001157e1122024857a2b8ffcb9c730e165d
vim +410 arch/x86/kernel/kvm.c

4716276184ec67 Brijesh Singh 2017-10-20  406  
ec31b001157e11 Ashish Kalra  2020-04-30  407  #ifdef CONFIG_EFI
ec31b001157e11 Ashish Kalra  2020-04-30  408  static bool setup_kvm_sev_migration(void)
ec31b001157e11 Ashish Kalra  2020-04-30  409  {
ec31b001157e11 Ashish Kalra  2020-04-30 @410  	efi_char16_t efi_Sev_Live_Mig_support_name[] = L"SevLiveMigrationEnabled";
ec31b001157e11 Ashish Kalra  2020-04-30  411  	efi_guid_t efi_variable_guid = MEM_ENCRYPT_GUID;
ec31b001157e11 Ashish Kalra  2020-04-30  412  	efi_status_t status;
ec31b001157e11 Ashish Kalra  2020-04-30  413  	unsigned long size;
ec31b001157e11 Ashish Kalra  2020-04-30  414  	bool enabled;
ec31b001157e11 Ashish Kalra  2020-04-30  415  
ec31b001157e11 Ashish Kalra  2020-04-30  416  	if (!sev_live_migration_enabled())
ec31b001157e11 Ashish Kalra  2020-04-30  417  		return false;
ec31b001157e11 Ashish Kalra  2020-04-30  418  
ec31b001157e11 Ashish Kalra  2020-04-30  419  	size = sizeof(enabled);
ec31b001157e11 Ashish Kalra  2020-04-30  420  
ec31b001157e11 Ashish Kalra  2020-04-30  421  	if (!efi_enabled(EFI_RUNTIME_SERVICES)) {
ec31b001157e11 Ashish Kalra  2020-04-30  422  		pr_info("setup_kvm_sev_migration: no efi\n");
ec31b001157e11 Ashish Kalra  2020-04-30  423  		return false;
ec31b001157e11 Ashish Kalra  2020-04-30  424  	}
ec31b001157e11 Ashish Kalra  2020-04-30  425  
ec31b001157e11 Ashish Kalra  2020-04-30  426  	/* Get variable contents into buffer */
ec31b001157e11 Ashish Kalra  2020-04-30  427  	status = efi.get_variable(efi_Sev_Live_Mig_support_name,
ec31b001157e11 Ashish Kalra  2020-04-30  428  				  &efi_variable_guid, NULL, &size, &enabled);
ec31b001157e11 Ashish Kalra  2020-04-30  429  
ec31b001157e11 Ashish Kalra  2020-04-30  430  	if (status == EFI_NOT_FOUND) {
ec31b001157e11 Ashish Kalra  2020-04-30  431  		pr_info("setup_kvm_sev_migration: variable not found\n");
ec31b001157e11 Ashish Kalra  2020-04-30  432  		return false;
ec31b001157e11 Ashish Kalra  2020-04-30  433  	}
ec31b001157e11 Ashish Kalra  2020-04-30  434  
ec31b001157e11 Ashish Kalra  2020-04-30  435  	if (status != EFI_SUCCESS) {
ec31b001157e11 Ashish Kalra  2020-04-30  436  		pr_info("setup_kvm_sev_migration: get_variable fail\n");
ec31b001157e11 Ashish Kalra  2020-04-30  437  		return false;
ec31b001157e11 Ashish Kalra  2020-04-30  438  	}
ec31b001157e11 Ashish Kalra  2020-04-30  439  
ec31b001157e11 Ashish Kalra  2020-04-30  440  	if (enabled == 0) {
ec31b001157e11 Ashish Kalra  2020-04-30  441  		pr_info("setup_kvm_sev_migration: live migration disabled in OVMF\n");
ec31b001157e11 Ashish Kalra  2020-04-30  442  		return false;
ec31b001157e11 Ashish Kalra  2020-04-30  443  	}
ec31b001157e11 Ashish Kalra  2020-04-30  444  
ec31b001157e11 Ashish Kalra  2020-04-30  445  	pr_info("setup_kvm_sev_migration: live migration enabled in OVMF\n");
ec31b001157e11 Ashish Kalra  2020-04-30  446  	wrmsrl(MSR_KVM_SEV_LIVE_MIG_EN, KVM_SEV_LIVE_MIGRATION_ENABLED);
ec31b001157e11 Ashish Kalra  2020-04-30  447  
ec31b001157e11 Ashish Kalra  2020-04-30  448  	return true;
ec31b001157e11 Ashish Kalra  2020-04-30  449  }
ec31b001157e11 Ashish Kalra  2020-04-30  450  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

^ permalink raw reply	[flat|nested] 4+ messages in thread
* [PATCH v7 00/18] Add AMD SEV guest live migration support
@ 2020-04-30  8:39 Ashish Kalra
  2020-04-30  8:46 ` [PATCH v7 16/18] KVM: x86: Add guest support for detecting and enabling SEV Live Migration feature Ashish Kalra
  0 siblings, 1 reply; 4+ messages in thread
From: Ashish Kalra @ 2020-04-30  8:39 UTC (permalink / raw)
  To: pbonzini
  Cc: tglx, mingo, hpa, joro, bp, thomas.lendacky, x86, kvm,
	linux-kernel, srutherford, rientjes, venu.busireddy,
	brijesh.singh

From: Ashish Kalra <ashish.kalra@amd.com>

The series add support for AMD SEV guest live migration commands. To protect the
confidentiality of an SEV protected guest memory while in transit we need to
use the SEV commands defined in SEV API spec [1].

SEV guest VMs have the concept of private and shared memory. Private memory
is encrypted with the guest-specific key, while shared memory may be encrypted
with hypervisor key. The commands provided by the SEV FW are meant to be used
for the private memory only. The patch series introduces a new hypercall.
The guest OS can use this hypercall to notify the page encryption status.
If the page is encrypted with guest specific-key then we use SEV command during
the migration. If page is not encrypted then fallback to default.

The patch adds new ioctls KVM_{SET,GET}_PAGE_ENC_BITMAP. The ioctl can be used
by the qemu to get the page encrypted bitmap. Qemu can consult this bitmap
during the migration to know whether the page is encrypted.

[1] https://developer.amd.com/wp-content/resources/55766.PDF

Changes since v6:
- Rebasing to mainline and refactoring to the new split SVM
  infrastructre.
- Move to static allocation of the unified Page Encryption bitmap
  instead of the dynamic resizing of the bitmap, the static allocation
  is done implicitly by extending kvm_arch_commit_memory_region() callack
  to add svm specific x86_ops which can read the userspace provided memory
  region/memslots and calculate the amount of guest RAM managed by the KVM
  and grow the bitmap.
- Fixed KVM_SET_PAGE_ENC_BITMAP ioctl to set the whole bitmap instead
  of simply clearing specific bits.
- Removed KVM_PAGE_ENC_BITMAP_RESET ioctl, which is now performed using
  KVM_SET_PAGE_ENC_BITMAP.
- Extended guest support for enabling Live Migration feature by adding a
  check for UEFI environment variable indicating OVMF support for Live
  Migration feature and additionally checking for KVM capability for the
  same feature. If not booted under EFI, then we simply check for KVM
  capability.
- Add hypervisor specific hypercall for SEV live migration by adding
  a new paravirt callback as part of x86_hyper_runtime.
  (x86 hypervisor specific runtime callbacks)
- Moving MSR handling for MSR_KVM_SEV_LIVE_MIG_EN into svm/sev code 
  and adding check for SEV live migration enabled by guest in the 
  KVM_GET_PAGE_ENC_BITMAP ioctl.
- Instead of the complete __bss_decrypted section, only specific variables
  such as hv_clock_boot and wall_clock are marked as decrypted in the
  page encryption bitmap

Changes since v5:
- Fix build errors as
  Reported-by: kbuild test robot <lkp@intel.com>

Changes since v4:
- Host support has been added to extend KVM capabilities/feature bits to 
  include a new KVM_FEATURE_SEV_LIVE_MIGRATION, which the guest can
  query for host-side support for SEV live migration and a new custom MSR
  MSR_KVM_SEV_LIVE_MIG_EN is added for guest to enable the SEV live
  migration feature.
- Ensure that _bss_decrypted section is marked as decrypted in the
  page encryption bitmap.
- Fixing KVM_GET_PAGE_ENC_BITMAP ioctl to return the correct bitmap
  as per the number of pages being requested by the user. Ensure that
  we only copy bmap->num_pages bytes in the userspace buffer, if
  bmap->num_pages is not byte aligned we read the trailing bits
  from the userspace and copy those bits as is. This fixes guest
  page(s) corruption issues observed after migration completion.
- Add kexec support for SEV Live Migration to reset the host's
  page encryption bitmap related to kernel specific page encryption
  status settings before we load a new kernel by kexec. We cannot
  reset the complete page encryption bitmap here as we need to
  retain the UEFI/OVMF firmware specific settings.

Changes since v3:
- Rebasing to mainline and testing.
- Adding a new KVM_PAGE_ENC_BITMAP_RESET ioctl, which resets the 
  page encryption bitmap on a guest reboot event.
- Adding a more reliable sanity check for GPA range being passed to
  the hypercall to ensure that guest MMIO ranges are also marked
  in the page encryption bitmap.

Changes since v2:
 - reset the page encryption bitmap on vcpu reboot

Changes since v1:
 - Add support to share the page encryption between the source and target
   machine.
 - Fix review feedbacks from Tom Lendacky.
 - Add check to limit the session blob length.
 - Update KVM_GET_PAGE_ENC_BITMAP icotl to use the base_gfn instead of
   the memory slot when querying the bitmap.


Ashish Kalra (7):
  x86/paravirt: Add hypervisor specific hypercall for SEV live
    migration.
  KVM: SVM: Add support for static allocation of unified Page Encryption
    Bitmap.
  KVM: x86: Introduce new KVM_FEATURE_SEV_LIVE_MIGRATION feature &
    Custom MSR.
  EFI: Introduce the new AMD Memory Encryption GUID.
  KVM: x86: Add guest support for detecting and enabling SEV Live
    Migration feature.
  KVM: x86: Mark _bss_decrypted section variables as decrypted in page
    encryption bitmap.
  KVM: x86: Add kexec support for SEV Live Migration.

Brijesh Singh (11):
  KVM: SVM: Add KVM_SEV SEND_START command
  KVM: SVM: Add KVM_SEND_UPDATE_DATA command
  KVM: SVM: Add KVM_SEV_SEND_FINISH command
  KVM: SVM: Add support for KVM_SEV_RECEIVE_START command
  KVM: SVM: Add KVM_SEV_RECEIVE_UPDATE_DATA command
  KVM: SVM: Add KVM_SEV_RECEIVE_FINISH command
  KVM: x86: Add AMD SEV specific Hypercall3
  KVM: X86: Introduce KVM_HC_PAGE_ENC_STATUS hypercall
  KVM: x86: Introduce KVM_GET_PAGE_ENC_BITMAP ioctl
  mm: x86: Invoke hypercall when page encryption status is changed
  KVM: x86: Introduce KVM_SET_PAGE_ENC_BITMAP ioctl

 .../virt/kvm/amd-memory-encryption.rst        | 120 +++
 Documentation/virt/kvm/api.rst                |  71 ++
 Documentation/virt/kvm/cpuid.rst              |   5 +
 Documentation/virt/kvm/hypercalls.rst         |  15 +
 Documentation/virt/kvm/msr.rst                |  10 +
 arch/x86/include/asm/kvm_host.h               |   7 +
 arch/x86/include/asm/kvm_para.h               |  12 +
 arch/x86/include/asm/mem_encrypt.h            |  11 +
 arch/x86/include/asm/paravirt.h               |  10 +
 arch/x86/include/asm/paravirt_types.h         |   2 +
 arch/x86/include/asm/x86_init.h               |  10 +-
 arch/x86/include/uapi/asm/kvm_para.h          |   5 +
 arch/x86/kernel/kvm.c                         | 102 +++
 arch/x86/kernel/kvmclock.c                    |  12 +
 arch/x86/kernel/paravirt.c                    |   1 +
 arch/x86/kvm/svm/sev.c                        | 723 +++++++++++++++++-
 arch/x86/kvm/svm/svm.c                        |  21 +
 arch/x86/kvm/svm/svm.h                        |   9 +
 arch/x86/kvm/vmx/vmx.c                        |   1 +
 arch/x86/kvm/x86.c                            |  35 +
 arch/x86/mm/mem_encrypt.c                     |  69 +-
 arch/x86/mm/pat/set_memory.c                  |   7 +
 include/linux/efi.h                           |   1 +
 include/linux/psp-sev.h                       |   8 +-
 include/uapi/linux/kvm.h                      |  52 ++
 include/uapi/linux/kvm_para.h                 |   1 +
 26 files changed, 1310 insertions(+), 10 deletions(-)

-- 
2.17.1


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2020-05-01 13:39 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2020-05-01 13:39 [PATCH v7 16/18] KVM: x86: Add guest support for detecting and enabling SEV Live Migration feature kbuild test robot
  -- strict thread matches above, loose matches on Subject: below --
2020-04-30  8:39 [PATCH v7 00/18] Add AMD SEV guest live migration support Ashish Kalra
2020-04-30  8:46 ` [PATCH v7 16/18] KVM: x86: Add guest support for detecting and enabling SEV Live Migration feature Ashish Kalra
2020-04-30 16:42   ` kbuild test robot
2020-04-30 16:42     ` kbuild test robot

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