dc87275f47
Move the core of SMM hflags modifications into kvm_smm_changed() and use kvm_smm_changed() in enter_smm(). Clear HF_SMM_INSIDE_NMI_MASK for leaving SMM but do not set it for entering SMM. If the vCPU is executing outside of SMM, the flag should unequivocally be cleared, e.g. this technically fixes a benign bug where the flag could be left set after KVM_SET_VCPU_EVENTS, but the reverse is not true as NMI blocking depends on pre-SMM state or userspace input. Note, this adds an extra kvm_mmu_reset_context() to enter_smm(). The extra/early reset isn't strictly necessary, and in a way can never be necessary since the vCPU/MMU context is in a half-baked state until the final context reset at the end of the function. But, enter_smm() is not a hot path, and exploding on an invalid root_hpa is probably better than having a stale SMM flag in the MMU role; it's at least no worse. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210609185619.992058-6-seanjc@google.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.