14c2bf81fc
Under the case of nested on nested (L0, L1, L2 are all hypervisors), we do not support emulation of the vVMLOAD/VMSAVE feature, the L0 hypervisor can inject the proper #VMEXIT to inform L1 of what is happening and L1 can avoid invoking the #GP workaround. For this reason we turns on guest VM's X86_FEATURE_SVME_ADDR_CHK bit for KVM running inside VM to receive the notification and change behavior. Similarly we check if vcpu is under guest mode before emulating the vmware-backdoor instructions. For the case of nested on nested, we let the guest handle it. Co-developed-by: Bandan Das <bsd@redhat.com> Signed-off-by: Bandan Das <bsd@redhat.com> Signed-off-by: Wei Huang <wei.huang2@amd.com> Tested-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20210126081831.570253-5-wei.huang2@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.