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Gautham R. Shenoy
5f221c3ca1
The lower 8 bits of core_idle_state_ptr tracks the number of non-idle threads in the core. This is supposed to be initialized to bit-map corresponding to the threads_per_core. However, currently it is initialized to PNV_CORE_IDLE_THREAD_BITS (0xFF). This is correct for POWER8 which has 8 threads per core, but not for POWER9 which has 4 threads per core. As a result, on POWER9, core_idle_state_ptr gets initialized to 0xFF. In case when all the threads of the core are idle, the bits corresponding tracking the idle-threads are non-zero. As a result, the idle entry/exit code fails to save/restore per-core hypervisor state since it assumes that there are threads in the cores which are still active. Fix this by correctly initializing the lower bits of the core_idle_state_ptr on the basis of threads_per_core. Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. 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.