linux/arch/x86/kernel
Prarit Bhargava 2a51fe083e arch/x86: Handle non enumerated CPU after physical hotplug
When a CPU is physically added to a system then the MADT table is not
updated.

If subsequently a kdump kernel is started on that physically added CPU then
the ACPI enumeration fails to provide the information for this CPU which is
now the boot CPU of the kdump kernel.

As a consequence, generic_processor_info() is not invoked for that CPU so
the number of enumerated processors is 0 and none of the initializations,
including the logical package id management, are performed.

We have code which relies on the correctness of the logical package map and
other information which is initialized via generic_processor_info().
Executing such code will result in undefined behaviour or kernel crashes.

This problem applies only to the kdump kernel because a normal kexec will
switch to the original boot CPU, which is enumerated in MADT, before
jumping into the kexec kernel.

The boot code already has a check for num_processors equal 0 in
prefill_possible_map(). We can use that check as an indicator that the
enumeration of the boot CPU did not happen and invoke generic_processor_info()
for it. That initializes the relevant data for the boot CPU and therefore
prevents subsequent failure.

[ tglx: Refined the code and rewrote the changelog ]

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Fixes: 1f12e32f4c ("x86/topology: Create logical package id")
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: dyoung@redhat.com
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: kexec@lists.infradead.org
Link: http://lkml.kernel.org/r/1475514432-27682-1-git-send-email-prarit@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-10-07 15:22:15 +02:00
..
acpi Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-10-03 16:13:28 -07:00
apic x86/irq: Prevent force migration of irqs which are not in the vector domain 2016-10-04 13:13:47 +02:00
cpu x86/vmware: Skip lapic calibration on VMware 2016-10-05 11:43:30 +02:00
fpu x86/asm: Move the thread_info::status field to thread_struct 2016-09-15 08:25:12 +02:00
kprobes x86: Migrate exception table users off module.h and onto extable.h 2016-09-20 01:05:43 +02:00
.gitignore
alternative.c x86/asm: Stop depending on ptrace.h in alternative.h 2016-04-29 11:56:40 +02:00
amd_gart_64.c dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
amd_nb.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
apb_timer.c x86/apb_timer: Convert to hotplug state machine 2016-07-15 10:40:22 +02:00
aperture_64.c param: convert some "on"/"off" users to strtobool 2016-03-17 15:09:34 -07:00
apm_32.c x86/apm32: Remove paravirt_enabled() use 2016-04-22 10:29:03 +02:00
asm-offsets_32.c sched/x86: Rewrite the switch_to() code 2016-08-24 12:31:41 +02:00
asm-offsets_64.c sched/x86: Rewrite the switch_to() code 2016-08-24 12:31:41 +02:00
asm-offsets.c x86: Move thread_info into task_struct 2016-09-15 08:25:13 +02:00
audit_64.c
bootflag.c
check.c
cpuid.c
crash_dump_32.c
crash_dump_64.c
crash.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
devicetree.c x86/cpufeature: Replace cpu_has_apic with boot_cpu_has() usage 2016-04-13 11:37:41 +02:00
doublefault.c
dumpstack_32.c x86/dumpstack: Remove dump_trace() and related callbacks 2016-09-20 08:29:34 +02:00
dumpstack_64.c x86/dumpstack: Remove dump_trace() and related callbacks 2016-09-20 08:29:34 +02:00
dumpstack.c x86/dumpstack: Fix show_stack() task pointer regression 2016-09-20 23:36:37 +02:00
e820.c x86/boot: Fix kdump, cleanup aborted E820_PRAM max_pfn manipulation 2016-09-22 12:26:48 +02:00
early_printk.c x86: Fix misspellings in comments 2016-02-24 08:44:58 +01:00
early-quirks.c x86/e820: Prepare e280 code for switch to dynamic storage 2016-09-21 15:02:12 +02:00
ebda.c x86/boot: Simplify EBDA-vs-BIOS reservation logic 2016-07-22 11:46:01 +02:00
espfix_64.c x86: get rid of superfluous __GFP_REPEAT 2016-06-24 17:23:52 -07:00
ftrace.c ftrace/x86: Implement HAVE_FUNCTION_GRAPH_RET_ADDR_PTR 2016-08-24 12:15:15 +02:00
head32.c x86/boot: Run reserve_bios_regions() after we initialize the memory map 2016-08-11 11:14:59 +02:00
head64.c x86/boot: Run reserve_bios_regions() after we initialize the memory map 2016-08-11 11:14:59 +02:00
head_32.S x86/asm/head: Rename 'stack_start' -> 'initial_stack' 2016-08-18 18:41:29 +02:00
head_64.S x86/head: Remove useless zeroed word 2016-08-18 18:41:30 +02:00
hpet.c x86/hpet: Reduce HPET counter read contention 2016-09-09 15:16:19 +02:00
hw_breakpoint.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
i386_ksyms_32.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
i8237.c
i8253.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
i8259.c
io_delay.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
ioport.c x86/iopl: Fix iopl capability check on Xen PV 2016-03-17 09:49:27 +01:00
irq_32.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
irq_64.c x86: Move thread_info into task_struct 2016-09-15 08:25:13 +02:00
irq_work.c
irq.c x86/irq: Do not substract irq_tlb_count from irq_call_count 2016-08-11 11:14:59 +02:00
irqinit.c
jump_label.c x86/asm: Stop depending on ptrace.h in alternative.h 2016-04-29 11:56:40 +02:00
kdebugfs.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
kexec-bzimage64.c x86/e820: Prepare e280 code for switch to dynamic storage 2016-09-21 15:02:12 +02:00
kgdb.c sched/x86: Add 'struct inactive_task_frame' to better document the sleeping task stack frame 2016-08-24 12:27:41 +02:00
ksysfs.c x86: Apply more __ro_after_init and const 2016-08-10 14:55:05 +02:00
kvm.c Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-10-03 19:43:08 -07:00
kvmclock.c Merge branch 'linus' into x86/asm, to pick up recent fixes 2016-09-15 08:24:53 +02:00
ldt.c x86/mm: Factor out LDT init from context init 2016-02-18 19:46:31 +01:00
machine_kexec_32.c
machine_kexec_64.c kexec: provide arch_kexec_protect(unprotect)_crashkres() 2016-05-23 17:04:14 -07:00
Makefile x86/unwind: Add new unwind interface and implementations 2016-09-20 08:29:33 +02:00
mcount_64.S ftrace/x86: Set ftrace_stub to weak to prevent gcc from using short jumps to it 2016-05-20 13:28:40 -04:00
mmconf-fam10h_64.c
module.c x86/asm: Stop depending on ptrace.h in alternative.h 2016-04-29 11:56:40 +02:00
mpparse.c x86/mm/numa: Open code function early_get_boot_cpu_id() 2016-08-15 08:51:54 +02:00
msr.c
nmi_selftest.c
nmi.c x86: include linux/ratelimit.h in nmi.c 2016-06-06 17:10:15 +02:00
paravirt_patch_32.c x86, locking/spinlocks: Remove ticket (spin)lock implementation 2016-09-30 10:56:00 +02:00
paravirt_patch_64.c x86, locking/spinlocks: Remove ticket (spin)lock implementation 2016-09-30 10:56:00 +02:00
paravirt-spinlocks.c x86, locking/spinlocks: Remove ticket (spin)lock implementation 2016-09-30 10:56:00 +02:00
paravirt.c x86/asm: Get rid of __read_cr4_safe() 2016-09-30 12:40:12 +02:00
pci-calgary_64.c dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
pci-dma.c dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
pci-iommu_table.c x86: Fix non-static inlines 2016-04-16 13:21:40 +02:00
pci-nommu.c dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
pci-swiotlb.c dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
pcspeaker.c
perf_regs.c
platform-quirks.c x86/boot: Reorganize and clean up the BIOS area reservation code 2016-07-21 10:11:57 +02:00
pmem.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
probe_roms.c
process_32.c x86/asm: Get rid of __read_cr4_safe() 2016-09-30 12:40:12 +02:00
process_64.c Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-10-03 17:29:01 -07:00
process.c x86/process: Pin the target stack in get_wchan() 2016-09-16 09:18:53 +02:00
ptrace.c Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-10-03 17:29:01 -07:00
pvclock.c pvclock: introduce seqcount-like API 2016-08-04 13:52:21 +02:00
quirks.c x86/mce: Add PCI quirks to identify Xeons with machine check recovery 2016-09-05 11:47:31 +02:00
reboot_fixups_32.c
reboot.c x86: Apply more __ro_after_init and const 2016-08-10 14:55:05 +02:00
relocate_kernel_32.S
relocate_kernel_64.S
resource.c x86/e820: Prepare e280 code for switch to dynamic storage 2016-09-21 15:02:12 +02:00
rtc.c char/genrtc: x86: remove remnants of asm/rtc.h 2016-06-04 00:20:07 +02:00
setup_percpu.c Merge branch 'x86/mm' into x86/asm, to unify the two branches for simplicity 2016-09-08 08:41:52 +02:00
setup.c Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-10-03 16:46:53 -07:00
signal_compat.c x86/signal: Add SA_{X32,IA32}_ABI sa_flags 2016-09-14 21:28:11 +02:00
signal.c Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-10-03 17:29:01 -07:00
smp.c
smpboot.c arch/x86: Handle non enumerated CPU after physical hotplug 2016-10-07 15:22:15 +02:00
stacktrace.c x86/stacktrace: Convert save_stack_trace_*() to use the new unwinder 2016-09-20 08:29:33 +02:00
step.c
sys_x86_64.c
sysfb_efi.c Merge branch 'linus' into efi/core, to pick up fixes 2016-05-07 07:00:07 +02:00
sysfb_simplefb.c
sysfb.c
tboot.c x86/e820: Prepare e280 code for switch to dynamic storage 2016-09-21 15:02:12 +02:00
tce_64.c x86/cpufeature: Remove cpu_has_clflush 2016-03-31 13:35:09 +02:00
test_nx.c x86/mm: Always enable CONFIG_DEBUG_RODATA and remove the Kconfig option 2016-02-22 08:51:38 +01:00
test_rodata.c x86: Don't use module.h just for AUTHOR / LICENSE tags 2016-07-14 13:04:20 +02:00
time.c
tls.c x86/tls: Synchronize segment registers in set_thread_area() 2016-04-29 11:56:42 +02:00
tls.h
topology.c
trace_clock.c
tracepoint.c
traps.c x86/mm: Improve stack-overflow #PF handling 2016-09-08 08:47:20 +02:00
tsc_msr.c x86/tsc_msr: Remove irqoff around MSR-based TSC enumeration 2016-07-11 21:30:12 +02:00
tsc_sync.c
tsc.c x86/tsc: Add additional Intel CPU models to the crystal quirk list 2016-09-20 01:00:32 +02:00
unwind_frame.c x86/unwind: Add new unwind interface and implementations 2016-09-20 08:29:33 +02:00
unwind_guess.c x86/unwind: Fix oprofile module link error 2016-10-06 09:52:20 +02:00
uprobes.c uprobes/x86: Fix RIP-relative handling of EVEX-encoded instructions 2016-08-12 08:29:24 +02:00
verify_cpu.S
vm86_32.c x86, bitops: remove use of "sbb" to return CF 2016-06-08 12:41:20 -07:00
vmlinux.lds.S x86/boot: Move compressed kernel to the end of the decompression buffer 2016-04-29 11:03:29 +02:00
vsmp_64.c
x86_init.c x86: Apply more __ro_after_init and const 2016-08-10 14:55:05 +02:00
x8664_ksyms_64.c x86/mce: Improve memcpy_mcsafe() 2016-09-05 11:47:31 +02:00