• Thomas Gleixner's avatar
    x86/smpboot: Make logical package management more robust · a035dc67
    Thomas Gleixner authored
    commit 9d85eb91 upstream.
    
    The logical package management has several issues:
    
     - The APIC ids provided by ACPI are not required to be the same as the
       initial APIC id which can be retrieved by CPUID. The APIC ids provided
       by ACPI are those which are written by the BIOS into the APIC. The
       initial id is set by hardware and can not be changed. The hardware
       provided ids contain the real hardware package information.
    
       Especially AMD sets the effective APIC id different from the hardware id
       as they need to reserve space for the IOAPIC ids starting at id 0.
    
       As a consequence those machines trigger the currently active firmware
       bug printouts in dmesg, These are obviously wrong.
    
     - Virtual machines have their own interesting of enumerating APICs and
       packages which are not reliably covered by the current implementation.
    
    The sizing of the mapping array has been tweaked to be generously large to
    handle systems which provide a wrong core count when HT is disabled so the
    whole magic which checks for space in the physical hotplug case is not
    needed anymore.
    
    Simplify the whole machinery and do the mapping when the CPU starts and the
    CPUID derived physical package information is available. This solves the
    observed problems on AMD machines and works for the virtualization issues
    as well.
    
    Remove the extra call from XEN cpu bringup code as it is not longer
    required.
    
    Fixes: d49597fd ("x86/cpu: Deal with broken firmware (VMWare/XEN)")
    Reported-and-tested-by: default avatarBorislav Petkov <bp@suse.de>
    Tested-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
    Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
    Cc: Juergen Gross <jgross@suse.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: M. Vefa Bicakci <m.v.b@runbox.com>
    Cc: xen-devel <xen-devel@lists.xen.org>
    Cc: Charles (Chas) Williams <ciwillia@brocade.com>
    Cc: Borislav Petkov <bp@alien8.de>
    Cc: Alok Kataria <akataria@vmware.com>
    Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1612121102260.3429@nanosSigned-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    a035dc67
smpboot.c 41.1 KB