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Sean Christopherson c7d855c2af KVM: nVMX: Inject #UD if VMXON is attempted with incompatible CR0/CR4
Inject a #UD if L1 attempts VMXON with a CR0 or CR4 that is disallowed
per the associated nested VMX MSRs' fixed0/1 settings.  KVM cannot rely
on hardware to perform the checks, even for the few checks that have
higher priority than VM-Exit, as (a) KVM may have forced CR0/CR4 bits in
hardware while running the guest, (b) there may incompatible CR0/CR4 bits
that have lower priority than VM-Exit, e.g. CR0.NE, and (c) userspace may
have further restricted the allowed CR0/CR4 values by manipulating the
guest's nested VMX MSRs.

Note, despite a very strong desire to throw shade at Jim, commit
70f3aac964 ("kvm: nVMX: Remove superfluous VMX instruction fault checks")
is not to blame for the buggy behavior (though the comment...).  That
commit only removed the CR0.PE, EFLAGS.VM, and COMPATIBILITY mode checks
(though it did erroneously drop the CPL check, but that has already been
remedied).  KVM may force CR0.PE=1, but will do so only when also
forcing EFLAGS.VM=1 to emulate Real Mode, i.e. hardware will still #UD.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216033
Fixes: ec378aeef9 ("KVM: nVMX: Implement VMXON and VMXOFF")
Reported-by: Eric Li <ercli@ucdavis.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220607213604.3346000-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-07-28 13:22:26 -04:00
arch KVM: nVMX: Inject #UD if VMXON is attempted with incompatible CR0/CR4 2022-07-28 13:22:26 -04:00
block for-5.19/drivers-2022-06-02 2022-06-03 10:25:56 -07:00
certs Kbuild updates for v5.19 2022-05-26 12:09:50 -07:00
crypto This update includes the following changes: 2022-05-27 18:06:49 -07:00
Documentation KVM: s390x: Fixes and features for 5.20 2022-07-22 03:14:32 -04:00
drivers vfio-pci/zdev: different maxstbl for interpreted devices 2022-07-11 09:54:37 +02:00
fs fix for breakage in #work.fd this window 2022-06-05 17:14:03 -07:00
include KVM: s390x: Fixes and features for 5.20 2022-07-22 03:14:32 -04:00
init This set of changes updates init and user mode helper tasks to be 2022-06-03 16:03:05 -07:00
ipc These changes update the ipc sysctls so that they are fundamentally 2022-06-03 15:54:57 -07:00
kernel KVM/riscv fixes for 5.19, take #1 2022-06-09 09:45:00 -04:00
lib Bitmap patches for 5.19-rc1 2022-06-04 14:04:27 -07:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm Hot fixes for 5.19-rc1. 2022-06-05 17:05:38 -07:00
net bluetooth: don't use bitmaps for random flag accesses 2022-06-05 16:28:41 -07:00
samples drm for 5.19-rc1 2022-05-25 16:18:27 -07:00
scripts A set of objtool fixes: 2022-06-05 09:45:27 -07:00
security Cleanups (and one fix) around struct mount handling. 2022-06-04 19:00:05 -07:00
sound USB / Thunderbolt changes for 5.19-rc1 2022-06-03 11:17:49 -07:00
tools KVM: selftests: Add an option to run vCPUs while disabling dirty logging 2022-07-28 13:22:24 -04:00
usr Not a lot of material this cycle. Many singleton patches against various 2022-05-27 11:22:03 -07:00
virt KVM: debugfs: expose pid of vcpu threads 2022-06-24 12:44:33 -04:00
.clang-format clang-format: Fix space after for_each macros 2022-05-20 19:27:16 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore kbuild: split the second line of *.mod into *.usyms 2022-05-08 03:16:59 +09:00
.mailmap Hot fixes for 5.19-rc1. 2022-06-05 17:05:38 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: replace a Microchip AT91 maintainer 2022-02-09 11:30:01 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS KVM: s390/pci: enable zPCI for interpretive execution 2022-07-11 11:28:57 +02:00
Makefile Linux 5.19-rc1 2022-06-05 17:18:54 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.