cb00a70bd4
When using KVM_DIRTY_LOG_INITIALLY_SET, huge pages are not write-protected when dirty logging is enabled on the memslot. Instead they are write-protected once userspace invokes KVM_CLEAR_DIRTY_LOG for the first time and only for the specific sub-region being cleared. Enhance KVM_CLEAR_DIRTY_LOG to also try to split huge pages prior to write-protecting to avoid causing write-protection faults on vCPU threads. This also allows userspace to smear the cost of huge page splitting across multiple ioctls, rather than splitting the entire memslot as is the case when initially-all-set is not used. Signed-off-by: David Matlack <dmatlack@google.com> Message-Id: <20220119230739.2234394-17-dmatlack@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.