linux_dsm_epyc7002/arch/x86/kernel/apic
Sean Christopherson 7a22e03b0c x86/apic/x2apic: Fix a NULL pointer deref when handling a dying cpu
Check that the per-cpu cluster mask pointer has been set prior to
clearing a dying cpu's bit.  The per-cpu pointer is not set until the
target cpu reaches smp_callin() during CPUHP_BRINGUP_CPU, whereas the
teardown function, x2apic_dead_cpu(), is associated with the earlier
CPUHP_X2APIC_PREPARE.  If an error occurs before the cpu is awakened,
e.g. if do_boot_cpu() itself fails, x2apic_dead_cpu() will dereference
the NULL pointer and cause a panic.

  smpboot: do_boot_cpu failed(-22) to wakeup CPU#1
  BUG: kernel NULL pointer dereference, address: 0000000000000008
  RIP: 0010:x2apic_dead_cpu+0x1a/0x30
  Call Trace:
   cpuhp_invoke_callback+0x9a/0x580
   _cpu_up+0x10d/0x140
   do_cpu_up+0x69/0xb0
   smp_init+0x63/0xa9
   kernel_init_freeable+0xd7/0x229
   ? rest_init+0xa0/0xa0
   kernel_init+0xa/0x100
   ret_from_fork+0x35/0x40

Fixes: 023a611748 ("x86/apic/x2apic: Simplify cluster management")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20191001205019.5789-1-sean.j.christopherson@intel.com
2019-10-15 10:57:09 +02:00
..
apic_common.c x86/apic: Fix signedness bug in APIC ID validity checks 2018-04-10 16:46:39 +02:00
apic_flat_64.c x86/apic/flat64: Remove the IPI shorthand decision logic 2019-07-25 16:12:02 +02:00
apic_noop.c x86/apic: Cleanup the include maze 2019-07-25 16:11:57 +02:00
apic_numachip.c x86/apic: Consolidate the apic local headers 2019-07-25 16:11:58 +02:00
apic.c Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-09-17 12:04:39 -07:00
bigsmp_32.c Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-09-17 12:04:39 -07:00
hw_nmi.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
io_apic.c x86/apic: Fix arch_dynirq_lower_bound() bug for DT enabled machines 2019-08-26 12:11:23 +02:00
ipi.c x86/apic: Share common IPI helpers 2019-07-25 16:12:02 +02:00
local.h x86/apic/x2apic: Implement IPI shorthands support 2019-07-25 16:12:02 +02:00
Makefile x86/PCI: Remove unused HyperTransport interrupt support 2017-11-23 20:18:18 +01:00
msi.c x86/hpet: Move clockevents into channels 2019-06-28 00:57:24 +02:00
probe_32.c Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-09-17 12:04:39 -07:00
probe_64.c x86/apic/flat64: Remove the IPI shorthand decision logic 2019-07-25 16:12:02 +02:00
vector.c x86/apic/vector: Warn when vector space exhaustion breaks affinity 2019-08-28 14:44:08 +02:00
x2apic_cluster.c x86/apic/x2apic: Fix a NULL pointer deref when handling a dying cpu 2019-10-15 10:57:09 +02:00
x2apic_phys.c x86/apic/x2apic: Implement IPI shorthands support 2019-07-25 16:12:02 +02:00
x2apic_uv_x.c x86/apic/uv: Make x2apic_extra_bits static 2019-07-25 16:11:58 +02:00