Linux kernel modifications for the Kernel Hacking exam
c395fe1d8e
Currently, kvmppc_xive_release() and kvmppc_xive_native_release() clear kvm->arch.mmu_ready and call kick_all_cpus_sync() as a way of ensuring that no vcpus are executing in the guest. However, future patches will change the mutex associated with kvm->arch.mmu_ready to a new mutex that nests inside the vcpu mutexes, making it difficult to continue to use this method. In fact, taking the vcpu mutex for a vcpu excludes execution of that vcpu, and we already take the vcpu mutex around the call to kvmppc_xive_[native_]cleanup_vcpu(). Once the cleanup function is done and we release the vcpu mutex, the vcpu can execute once again, but because we have cleared vcpu->arch.xive_vcpu, vcpu->arch.irq_type, vcpu->arch.xive_esc_vaddr and vcpu->arch.xive_esc_raddr, that vcpu will not be going into XIVE code any more. Thus, once we have cleaned up all of the vcpus, we are safe to clean up the rest of the XIVE state, and we don't need to use kvm->arch.mmu_ready to hold off vcpu execution. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> |
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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.