Sean Christopherson f0d4379087 KVM: x86/mmu: Remove broken WARN that fires on 32-bit KVM w/ nested EPT
Remove a misguided WARN that attempts to detect the scenario where using
a special A/D tracking flag will set reserved bits on a non-MMIO spte.
The WARN triggers false positives when using EPT with 32-bit KVM because
of the !64-bit clause, which is just flat out wrong.  The whole A/D
tracking goo is specific to EPT, and one of the big selling points of EPT
is that EPT is decoupled from the host's native paging mode.

Drop the WARN instead of trying to salvage the check.  Keeping a check
specific to A/D tracking bits would essentially regurgitate the same code
that led to KVM needed the tracking bits in the first place.

A better approach would be to add a generic WARN on reserved bits being
set, which would naturally cover the A/D tracking bits, work for all
flavors of paging, and be self-documenting to some extent.

Fixes: 8a406c8953 ("KVM: x86/mmu: Rename and document A/D scheme for TDP SPTEs")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210622175739.3610207-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-06-24 18:00:35 -04:00
2021-05-07 00:26:34 -07:00
2021-05-14 19:41:32 -07:00
2021-05-16 15:27:44 -07:00

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.
Description
No description provided
Readme 3.4 GiB
Languages
C 97%
Assembly 1%
Shell 0.6%
Rust 0.5%
Python 0.4%
Other 0.3%