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Lorenzo Brescia
d95df95106
On VMX, if we exit and then re-enter immediately without leaving the vmx_vcpu_run() function, the kvm_entry event is not logged. That means we will see one (or more) kvm_exit, without its (their) corresponding kvm_entry, as shown here: CPU-1979 [002] 89.871187: kvm_entry: vcpu 1 CPU-1979 [002] 89.871218: kvm_exit: reason MSR_WRITE CPU-1979 [002] 89.871259: kvm_exit: reason MSR_WRITE It also seems possible for a kvm_entry event to be logged, but then we leave vmx_vcpu_run() right away (if vmx->emulation_required is true). In this case, we will have a spurious kvm_entry event in the trace. Fix these situations by moving trace_kvm_entry() inside vmx_vcpu_run() (where trace_kvm_exit() already is). A trace obtained with this patch applied looks like this: CPU-14295 [000] 8388.395387: kvm_entry: vcpu 0 CPU-14295 [000] 8388.395392: kvm_exit: reason MSR_WRITE CPU-14295 [000] 8388.395393: kvm_entry: vcpu 0 CPU-14295 [000] 8388.395503: kvm_exit: reason EXTERNAL_INTERRUPT Of course, not calling trace_kvm_entry() in common x86 code any longer means that we need to adjust the SVM side of things too. Signed-off-by: Lorenzo Brescia <lorenzo.brescia@edu.unito.it> Signed-off-by: Dario Faggioli <dfaggioli@suse.com> Message-Id: <160873470698.11652.13483635328769030605.stgit@Wayrath> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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.