mirror of
https://github.com/raspberrypi/linux.git
synced 2025-12-06 01:49:46 +00:00
922d2f0458
commitdc55b3c3f6upstream. The APM lists the DbgCtlMsr field as being tracked by the VMCB_LBR clean bit. Always clear the bit when MSR_IA32_DEBUGCTLMSR is updated. The history is complicated, it was correctly cleared for L1 before commit1d5a1b5860("KVM: x86: nSVM: correctly virtualize LBR msrs when L2 is running"). At that point svm_set_msr() started to rely on svm_update_lbrv() to clear the bit, but when nested virtualization is enabled the latter does not always clear it even if MSR_IA32_DEBUGCTLMSR changed. Go back to clearing it directly in svm_set_msr(). Fixes:1d5a1b5860("KVM: x86: nSVM: correctly virtualize LBR msrs when L2 is running") Reported-by: Matteo Rizzo <matteorizzo@google.com> Reported-by: evn@google.com Co-developed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Jim Mattson <jmattson@google.com> Signed-off-by: Yosry Ahmed <yosry.ahmed@linux.dev> Link: https://patch.msgid.link/20251108004524.1600006-2-yosry.ahmed@linux.dev Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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 reStructuredText 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.