Marc Zyngier
28e81c6270
KVM: arm64: Don't corrupt tpidr_el2 on failed HVC call
The hyp-init code starts by stashing a register in TPIDR_EL2 in in order to free a register. This happens no matter if the HVC call is legal or not. Although nothing wrong seems to come out of it, it feels odd to alter the EL2 state for something that eventually returns an error. Instead, use the fact that we know exactly which bits of the __kvm_hyp_init call are non-zero to perform the check with a series of EOR/ROR instructions, combined with a build-time check that the value is the one we expect. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20201026095116.72051-2-maz@kernel.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.
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