x86/smpboot: Make logical package management more robust

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: d49597fd3bc7 ("x86/cpu: Deal with broken firmware (VMWare/XEN)")
Reported-and-tested-by: Borislav Petkov <bp@suse.de>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Thomas 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>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1612121102260.3429@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 0 insertions, 15 deletions

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index bb47e5eacd44..5b7e43eff139 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2160,21 +2160,6 @@ int __generic_processor_info(int apicid, int version, bool enabled)
 	}
 
 	/*
-	 * This can happen on physical hotplug. The sanity check at boot time
-	 * is done from native_smp_prepare_cpus() after num_possible_cpus() is
-	 * established.
-	 */
-	if (topology_update_package_map(apicid, cpu) < 0) {
-		int thiscpu = max + disabled_cpus;
-
-		pr_warning("APIC: Package limit reached. Processor %d/0x%x ignored.\n",
-			   thiscpu, apicid);
-
-		disabled_cpus++;
-		return -ENOSPC;
-	}
-
-	/*
 	 * Validate version
 	 */
 	if (version == 0x0) {