mirror of https://gitee.com/openkylin/linux.git
ca9f494267
A pseries guest can be run as secure guest on Ultravisor-enabled POWER platforms. On such platforms, this driver will be used to manage the movement of guest pages between the normal memory managed by hypervisor (HV) and secure memory managed by Ultravisor (UV). HV is informed about the guest's transition to secure mode via hcalls: H_SVM_INIT_START: Initiate securing a VM H_SVM_INIT_DONE: Conclude securing a VM As part of H_SVM_INIT_START, register all existing memslots with the UV. H_SVM_INIT_DONE call by UV informs HV that transition of the guest to secure mode is complete. These two states (transition to secure mode STARTED and transition to secure mode COMPLETED) are recorded in kvm->arch.secure_guest. Setting these states will cause the assembly code that enters the guest to call the UV_RETURN ucall instead of trying to enter the guest directly. Migration of pages betwen normal and secure memory of secure guest is implemented in H_SVM_PAGE_IN and H_SVM_PAGE_OUT hcalls. H_SVM_PAGE_IN: Move the content of a normal page to secure page H_SVM_PAGE_OUT: Move the content of a secure page to normal page Private ZONE_DEVICE memory equal to the amount of secure memory available in the platform for running secure guests is created. Whenever a page belonging to the guest becomes secure, a page from this private device memory is used to represent and track that secure page on the HV side. The movement of pages between normal and secure memory is done via migrate_vma_pages() using UV_PAGE_IN and UV_PAGE_OUT ucalls. In order to prevent the device private pages (that correspond to pages of secure guest) from participating in KSM merging, H_SVM_PAGE_IN calls ksm_madvise() under read version of mmap_sem. However ksm_madvise() needs to be under write lock. Hence we call kvmppc_svm_page_in with mmap_sem held for writing, and it then downgrades to a read lock after calling ksm_madvise. [paulus@ozlabs.org - roll in patch "KVM: PPC: Book3S HV: Take write mmap_sem when calling ksm_madvise"] Signed-off-by: Bharata B Rao <bharata@linux.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> |
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.. | ||
boot | ||
configs | ||
crypto | ||
include | ||
kernel | ||
kvm | ||
lib | ||
math-emu | ||
mm | ||
net | ||
oprofile | ||
perf | ||
platforms | ||
purgatory | ||
sysdev | ||
tools | ||
xmon | ||
Kbuild | ||
Kconfig | ||
Kconfig.debug | ||
Makefile | ||
Makefile.postlink |