mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-10 13:59:45 -04:00
704fc6021b
If emulation is "rejected" by check_emulate_instruction(), try to unprotect and retry instruction execution before reporting the error to userspace. Currently, check_emulate_instruction() never signals failure when "unprotect and retry" is possible, but that will change in the future as both VMX and SVM will reject emulation due to coincident exception vectoring. E.g. if there is a write to a shadowed page table when vectoring an event, then unprotecting the gfn and retrying the instruction will allow the guest to make forward progress in most cases, i.e. will allow the vCPU to keep running instead of returning an error to userspace. This ensures that the subsequent patches won't make KVM exit to userspace when handling an intercepted #PF during vectoring without checking whether unprotect and retry is possible. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Ivan Orlov <iorlov@amazon.com> Link: https://lore.kernel.org/r/20241217181458.68690-4-iorlov@amazon.com [sean: massage changelog to clarify this is a nop for the current code] 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 reStructuredText 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.