mainlining shenanigans
0aa1837533
Reset the MMU context at vCPU INIT (and RESET for good measure) if CR0.PG was set prior to INIT. Simply re-initializing the current MMU is not sufficient as the current root HPA may not be usable in the new context. E.g. if TDP is disabled and INIT arrives while the vCPU is in long mode, KVM will fail to switch to the 32-bit pae_root and bomb on the next VM-Enter due to running with a 64-bit CR3 in 32-bit mode. This bug was papered over in both VMX and SVM, but still managed to rear its head in the MMU role on VMX. Because EFER.LMA=1 requires CR0.PG=1, kvm_calc_shadow_mmu_root_page_role() checks for EFER.LMA without first checking CR0.PG. VMX's RESET/INIT flow writes CR0 before EFER, and so an INIT with the vCPU in 64-bit mode will cause the hack-a-fix to generate the wrong MMU role. In VMX, the INIT issue is specific to running without unrestricted guest since unrestricted guest is available if and only if EPT is enabled. Commit |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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.