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bc7fe2f0b7
Drop handling of MSR_IA32_CR_PAT from mtrr.c now that SVM and VMX handle writes without bouncing through kvm_set_msr_common(). PAT isn't truly an MTRR even though it affects memory types, and more importantly KVM enables hardware virtualization of guest PAT (by NOT setting "ignore guest PAT") when a guest has non-coherent DMA, i.e. KVM doesn't need to zap SPTEs when the guest PAT changes. The read path is and always has been trivial, i.e. burying it in the MTRR code does more harm than good. WARN and continue for the PAT case in kvm_set_msr_common(), as that code is _currently_ reached if and only if KVM is buggy. Defer cleaning up the lack of symmetry between the read and write paths to a future patch. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230511233351.635053-7-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.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.