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.
Linus Torvalds
authored
Pull x86 cpuid updates from Borislav Petkov: - Cache the AMD debug registers in per-CPU variables to avoid MSR writes where possible, when supporting a debug registers swap feature for SEV-ES guests - Add support for AMD's version of eIBRS called Automatic IBRS which is a set-and-forget control of indirect branch restriction speculation resources on privilege change - Add support for a new x86 instruction - LKGS - Load kernel GS which is part of the FRED infrastructure - Reset SPEC_CTRL upon init to accomodate use cases like kexec which rediscover - Other smaller fixes and cleanups * tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/amd: Cache debug register values in percpu variables KVM: x86: Propagate the AMD Automatic IBRS feature to the guest x86/cpu: Support AMD Automatic IBRS x86/cpu, kvm: Add the SMM_CTL MSR not present feature x86/cpu, kvm: Add the Null Selector Clears Base feature x86/cpu, kvm: Move X86_FEATURE_LFENCE_RDTSC to its native leaf x86/cpu, kvm: Add the NO_NESTED_DATA_BP feature KVM: x86: Move open-coded CPUID leaf 0x80000021 EAX bit propagation code x86/cpu, kvm: Add support for CPUID_80000021_EAX x86/gsseg: Add the new <asm/gsseg.h> header to <asm/asm-prototypes.h> x86/gsseg: Use the LKGS instruction if available for load_gs_index() x86/gsseg: Move load_gs_index() to its own new header file x86/gsseg: Make asm_load_gs_index() take an u16 x86/opcode: Add the LKGS instruction to x86-opcode-map x86/cpufeature: Add the CPU feature bit for LKGS x86/bugs: Reset speculation control settings on init x86/cpu: Remove redundant extern x86_read_arch_cap_msr()