Sean Christopherson
0cbc60d44c
Use a u16 instead of a u32 to track the dirty/valid status of GPRs in the emulator. Unlike struct kvm_vcpu_arch, x86_emulate_ctxt tracks only the "true" GPRs, i.e. doesn't include RIP in its array, and so only needs to track 16 registers. Note, maxing out at 16 GPRs is a fundamental property of x86-64 and will not change barring a massive architecture update. Legacy x86 ModRM and SIB encodings use 3 bits for GPRs, i.e. support 8 registers. x86-64 uses a single bit in the REX prefix for each possible reference type to double the number of supported GPRs to 16 registers (4 bits). Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20220526210817.3428868-5-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.