65ac3a4fee
commit af9acbfc2c4b72c378d0b9a2ee023ed01055d3e2 upstream. When updating the affinity of a VPE, the VMOVP command is currently skipped if the two CPUs are part of the same VPE affinity. But this is wrong, as the doorbell corresponding to this VPE is still delivered on the 'old' CPU, which screws up the balancing. Furthermore, offlining that 'old' CPU results in doorbell interrupts generated for this VPE being discarded. The harsh reality is that VMOVP cannot be elided when a set_affinity() request occurs. It needs to be obeyed, and if an optimisation is to be made, it is at the point where the affinity change request is made (such as in KVM). Drop the VMOVP elision altogether, and only use the vpe_table_mask to try and stay within the same ITS affinity group if at all possible. Fixes: dd3f050a216e (irqchip/gic-v4.1: Implement the v4.1 flavour of VMOVP) Reported-by: Kunkun Jiang <jiangkunkun@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240213101206.2137483-4-maz@kernel.org 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 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.