mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-09-17 09:41:09 +02:00
Anup Patel
13acfec2db
The generic KVM has support for VCPU requests which can be used to do arch-specific work in the run-loop. We introduce remote HFENCE functions which will internally use VCPU requests instead of host SBI calls. Advantages of doing remote HFENCEs as VCPU requests are: 1) Multiple VCPUs of a Guest may be running on different Host CPUs so it is not always possible to determine the Host CPU mask for doing Host SBI call. For example, when VCPU X wants to do HFENCE on VCPU Y, it is possible that VCPU Y is blocked or in user-space (i.e. vcpu->cpu < 0). 2) To support nested virtualization, we will be having a separate shadow G-stage for each VCPU and a common host G-stage for the entire Guest/VM. The VCPU requests based remote HFENCEs helps us easily synchronize the common host G-stage and shadow G-stage of each VCPU without any additional IPI calls. This is also a preparatory patch for upcoming nested virtualization support where we will be having a shadow G-stage page table for each Guest VCPU. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
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.