Matt Fleming d7a702f0b1 perf/x86/intel/cqm: Do not access cpu_data() from CPU_UP_PREPARE handler ... Tony reports that booting his 144-cpu machine with maxcpus=10 triggers the following WARN_ON(): [ 21.045727] WARNING: CPU: 8 PID: 647 at arch/x86/kernel/cpu/perf_event_intel_cqm.c:1267 intel_cqm_cpu_prepare+0x75/0x90() [ 21.045744] CPU: 8 PID: 647 Comm: systemd-udevd Not tainted 4.2.0-rc4 #1 [ 21.045745] Hardware name: Intel Corporation BRICKLAND/BRICKLAND, BIOS BRHSXSD1.86B.0066.R00.1506021730 06/02/2015 [ 21.045747] 0000000000000000 0000000082771b09 ffff880856333ba8 ffffffff81669b67 [ 21.045748] 0000000000000000 0000000000000000 ffff880856333be8 ffffffff8107b02a [ 21.045750] ffff88085b789800 ffff88085f68a020 ffffffff819e2470 000000000000000a [ 21.045750] Call Trace: [ 21.045757] [<ffffffff81669b67>] dump_stack+0x45/0x57 [ 21.045759] [<ffffffff8107b02a>] warn_slowpath_common+0x8a/0xc0 [ 21.045761] [<ffffffff8107b15a>] warn_slowpath_null+0x1a/0x20 [ 21.045762] [<ffffffff81036725>] intel_cqm_cpu_prepare+0x75/0x90 [ 21.045764] [<ffffffff81036872>] intel_cqm_cpu_notifier+0x42/0x160 [ 21.045767] [<ffffffff8109a33d>] notifier_call_chain+0x4d/0x80 [ 21.045769] [<ffffffff8109a44e>] __raw_notifier_call_chain+0xe/0x10 [ 21.045770] [<ffffffff8107b538>] _cpu_up+0xe8/0x190 [ 21.045771] [<ffffffff8107b65a>] cpu_up+0x7a/0xa0 [ 21.045774] [<ffffffff8165e920>] cpu_subsys_online+0x40/0x90 [ 21.045777] [<ffffffff81433b37>] device_online+0x67/0x90 [ 21.045778] [<ffffffff81433bea>] online_store+0x8a/0xa0 [ 21.045782] [<ffffffff81430e78>] dev_attr_store+0x18/0x30 [ 21.045785] [<ffffffff8126b6ba>] sysfs_kf_write+0x3a/0x50 [ 21.045786] [<ffffffff8126ad40>] kernfs_fop_write+0x120/0x170 [ 21.045789] [<ffffffff811f0b77>] __vfs_write+0x37/0x100 [ 21.045791] [<ffffffff811f38b8>] ? __sb_start_write+0x58/0x110 [ 21.045795] [<ffffffff81296d2d>] ? security_file_permission+0x3d/0xc0 [ 21.045796] [<ffffffff811f1279>] vfs_write+0xa9/0x190 [ 21.045797] [<ffffffff811f2075>] SyS_write+0x55/0xc0 [ 21.045800] [<ffffffff81067300>] ? do_page_fault+0x30/0x80 [ 21.045804] [<ffffffff816709ae>] entry_SYSCALL_64_fastpath+0x12/0x71 [ 21.045805] ---[ end trace fe228b836d8af405 ]--- The root cause is that CPU_UP_PREPARE is completely the wrong notifier action from which to access cpu_data(), because smp_store_cpu_info() won't have been executed by the target CPU at that point, which in turn means that ->x86_cache_max_rmid and ->x86_cache_occ_scale haven't been filled out. Instead let's invoke our handler from CPU_STARTING and rename it appropriately. Reported-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Kanaka Juvva <kanaka.d.juvva@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vikas Shivappa <vikas.shivappa@intel.com> Link: http://lkml.kernel.org/r/1438863163-14083-1-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>		2015-08-12 11:37:23 +02:00
..
acpi	Power management and ACPI material for v4.2-rc1	2015-06-23 14:18:07 -07:00
apic	x86/irq: Plug irq vector hotplug race	2015-07-07 11:54:04 +02:00
cpu	perf/x86/intel/cqm: Do not access cpu_data() from CPU_UP_PREPARE handler	2015-08-12 11:37:23 +02:00
fpu	x86/fpu: Disable dependent CPU features on "noxsave"	2015-07-21 08:20:42 +02:00
kprobes	Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-04-14 14:37:47 -07:00
.gitignore
alternative.c	Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-06-22 17:59:09 -07:00
amd_gart_64.c	x86: enable DMA CMA with swiotlb	2014-06-04 16:53:57 -07:00
amd_nb.c	x86/gart: Check for GART support before accessing GART registers	2015-05-06 11:15:53 +02:00
apb_timer.c	x86/intel-mid: Delay initialization of APB timer	2015-04-24 15:36:51 +02:00
aperture_64.c	x86/gart: Check for GART support before accessing GART registers	2015-05-06 11:15:53 +02:00
apm_32.c	cpuidle: Invert CPUIDLE_FLAG_TIME_VALID logic	2014-11-12 21:17:27 +01:00
asm-offsets_32.c	x86: Remove unused TI_cpu	2015-05-05 20:48:02 +02:00
asm-offsets_64.c	x86/asm/entry: (Re-)rename __NR_entry_INT80_compat_max to __NR_syscall_compat_max	2015-06-08 23:43:38 +02:00
asm-offsets.c	x86: Merge common 32-bit values in asm-offsets.c	2015-05-05 20:48:02 +02:00
audit_64.c	x86: hook up execveat system call	2014-12-13 12:42:51 -08:00
bootflag.c	x86: don't use module_init for non-modular core bootflag code	2015-06-16 14:12:34 -04:00
check.c	mm/memblock: add extra "flags" to memblock to allow selection of memory based on attribute	2015-06-24 17:49:44 -07:00
cpuid.c	x86, cpuid: Use PTR_ERR_OR_ZERO	2014-10-17 13:40:51 -07:00
crash_dump_32.c
crash_dump_64.c
crash.c	x86/mm: Decouple <linux/vmalloc.h> from <asm/io.h>	2015-06-03 12:02:00 +02:00
devicetree.c	Replace module_init with equivalent device_initcall in non modules.	2015-07-02 10:30:48 -07:00
doublefault.c
dumpstack_32.c	Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-04-13 13:23:34 -07:00
dumpstack_64.c	x86/kernel: Use kstack_end() in dumpstack_64.c	2015-02-23 18:37:13 +01:00
dumpstack.c	Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-04-13 13:23:34 -07:00
e820.c	The libnvdimm sub-system introduces, in addition to the libnvdimm-core,	2015-06-29 10:34:42 -07:00
early_printk.c	x86/earlyprintk: Allow early_printk() to use console style parameters like '115200n8'	2015-07-06 17:33:47 +02:00
early-quirks.c	Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux	2015-06-26 13:18:51 -07:00
espfix_64.c	x86/espfix: Init espfix on the boot CPU side	2015-07-06 15:00:34 +02:00
ftrace.c	module: remove mod arg from module_free, rename module_memfree().	2015-01-20 11:38:33 +10:30
head32.c	x86: Store a per-cpu shadow copy of CR4	2015-02-04 12:10:42 +01:00
head64.c	x86/kasan: Fix KASAN shadow region page tables	2015-07-06 14:53:13 +02:00
head_32.S	Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-06-22 17:59:09 -07:00
head_64.S	x86/kasan: Fix KASAN shadow region page tables	2015-07-06 14:53:13 +02:00
head.c
hpet.c	x86/hpet: Use proper hpet device number for MSI allocation	2015-06-21 16:38:40 +02:00
hw_breakpoint.c	perf/x86: Remove get_hbp_len and replace with bp_len	2014-12-03 15:14:30 +01:00
i386_ksyms_32.c	preempt: Use preempt_schedule_context() as the official tracing preemption point	2015-06-07 15:57:42 +02:00
i8237.c
i8253.c
i8259.c	x86/asm/entry/irq: Clean up IRQn_VECTOR macros	2015-05-10 12:34:28 +02:00
io_delay.c
ioport.c	x86/asm/entry: Rename 'init_tss' to 'cpu_tss'	2015-03-06 08:32:58 +01:00
iosf_mbi.c	x86/platform/intel/iosf: Add debugfs config option for IOSF	2014-09-19 13:08:43 +02:00
irq_32.c	x86/irq: Merge irq_regs & irq_stat	2015-05-10 12:34:27 +02:00
irq_64.c	x86/irq: Merge irq_regs & irq_stat	2015-05-10 12:34:27 +02:00
irq_work.c	x86: Consolidate irq entering inlines	2015-05-15 16:04:49 +02:00
irq.c	x86/irq: Retrieve irq data after locking irq_desc	2015-07-07 11:54:04 +02:00
irqinit.c	Merge branch 'x86/ras' into x86/core, to fix conflicts	2015-06-07 15:35:27 +02:00
jump_label.c
kdebugfs.c
kexec-bzimage64.c	x86/kexec: prepend elfcorehdr instead of appending it to the crash-kernel command-line.	2015-06-30 19:44:57 -07:00
kgdb.c	Linux 4.0-rc7	2015-04-08 09:01:54 +02:00
ksysfs.c
kvm.c	The bulk of the changes here is for x86. And for once it's not	2015-06-24 09:36:49 -07:00
kvmclock.c	x86: kvmclock: set scheduler clock stable	2015-05-29 14:01:52 +02:00
ldt.c	Revert "x86-64, modify_ldt: Make support for 16-bit segments a runtime option"	2014-05-21 10:22:59 -07:00
livepatch.c	livepatch: kernel: add support for live patching	2014-12-22 15:40:49 +01:00
machine_kexec_32.c	x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.h	2014-12-16 14:08:17 +01:00
machine_kexec_64.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching	2015-06-23 14:07:26 -07:00
Makefile	Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-06-22 17:59:09 -07:00
mcount_64.S	ftrace/fgraph/x86: Have prepare_ftrace_return() take ip as first parameter	2014-12-01 14:08:58 -05:00
mmconf-fam10h_64.c
module.c	x86/mm/KASLR: Propagate KASLR status to kernel proper	2015-04-03 15:26:15 +02:00
mpparse.c	x86: Cleanup irq_domain ops	2015-04-24 15:36:55 +02:00
msr.c	x86, msr: Use seek definitions instead of hard-coded values	2014-10-17 13:40:55 -07:00
nmi_selftest.c
nmi.c	x86/nmi/64: Improve nested NMI comments	2015-07-17 12:50:11 +02:00
paravirt_patch_32.c	locking/pvqspinlock, x86: Implement the paravirt qspinlock call patching	2015-05-08 12:37:09 +02:00
paravirt_patch_64.c	Merge branch 'locking/core' into x86/core, to prepare for dependent patch	2015-06-03 10:07:35 +02:00
paravirt-spinlocks.c	locking/pvqspinlock: Rename QUEUED_SPINLOCK to QUEUED_SPINLOCKS	2015-05-11 09:52:09 +02:00
paravirt.c	Merge branch 'linus' into x86/asm, before applying dependent patch	2015-05-08 13:33:33 +02:00
pci-calgary_64.c	x86, calgary: Use 8M TCE table size by default	2014-04-10 19:51:32 -07:00
pci-dma.c	x86: Deinline dma_free_attrs()	2015-05-05 20:48:02 +02:00
pci-iommu_table.c
pci-nommu.c
pci-swiotlb.c	x86/swiotlb: Try coherent allocations with __GFP_NOWARN	2015-06-11 08:28:38 +02:00
pcspeaker.c
perf_regs.c	perf/x86/64: Report regs_user->ax too in get_regs_user()	2015-04-11 13:08:53 +02:00
pmc_atom.c	x86: pmc_atom: Expose contents of PSS	2015-01-20 12:50:14 +01:00
pmem.c	libnvdimm: Set numa_node to NVDIMM devices	2015-06-26 11:23:38 -04:00
probe_roms.c
process_32.c	x86: opt into HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bit	2015-06-30 19:45:01 -07:00
process_64.c	x86: opt into HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bit	2015-06-30 19:45:01 -07:00
process.c	x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86	2015-07-18 03:42:51 +02:00
ptrace.c	x86/fpu: Factor out fpu/regset.h from fpu/internal.h	2015-05-19 15:48:06 +02:00
pvclock.c	x86: pvclock: Really remove the sched notifier for cross-cpu migrations	2015-04-27 15:49:30 +02:00
quirks.c	x86: HPET force enable for e6xx based systems	2014-09-15 17:53:35 -07:00
reboot_fixups_32.c
reboot.c	x86/reboot: Add ASRock Q1900DC-ITX mainboard reboot quirk	2015-04-01 14:08:09 +02:00
relocate_kernel_32.S	x86/asm: Optimize unnecessarily wide TEST instructions	2015-03-07 11:12:43 +01:00
relocate_kernel_64.S	x86/asm: Replace "MOVQ $imm, %reg" with MOVL	2015-04-01 13:17:39 +02:00
resource.c	x86: don't exclude low BIOS area when allocating address space for non-PCI cards	2014-07-16 12:29:36 -06:00
rtc.c	kernel.h: remove ancient __FUNCTION__ hack	2015-02-12 18:54:13 -08:00
setup_percpu.c	x86: Convert a few more per-CPU items to read-mostly ones	2014-11-04 20:13:28 +01:00
setup.c	Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-07-04 08:58:50 -07:00
signal.c	x86/fpu: Split out fpu/signal.h from fpu/internal.h for signal frame handling functions	2015-05-19 15:48:05 +02:00
smp.c	x86: Consolidate irq entering inlines	2015-05-15 16:04:49 +02:00
smpboot.c	genirq: Revert sparse irq locking around __cpu_up() and move it to x86 for now	2015-07-15 10:39:17 +02:00
stacktrace.c
step.c
sys_x86_64.c	x86/mm: Improve AMD Bulldozer ASLR workaround	2015-03-31 10:01:17 +02:00
sysfb_efi.c
sysfb_simplefb.c	x86/simplefb: Use PTR_ERR_OR_ZERO	2014-10-17 13:40:52 -07:00
sysfb.c	x86/sysfb: Use PTR_ERR_OR_ZERO	2014-10-17 13:40:52 -07:00
tboot.c
tce_64.c
test_nx.c
test_rodata.c	treewide: Fix typo in printk messages	2015-03-06 23:05:39 +01:00
time.c	x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()'	2015-03-23 11:14:17 +01:00
tls.c	x86, tls: Interpret an all-zero struct user_desc as "no segment"	2015-01-22 21:45:07 +01:00
tls.h
topology.c
trace_clock.c
tracepoint.c
traps.c	Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-06-22 17:59:09 -07:00
tsc_msr.c
tsc_sync.c	x86: Replace cpu_**_mask() with topology_**_cpumask()	2015-05-27 15:22:17 +02:00
tsc.c	x86/tsc: Let high latency PIT fail fast in quick_pit_calibrate()	2015-07-06 09:41:00 +02:00
uprobes.c	x86: Make is_64bit_mm() widely available	2015-06-09 12:24:32 +02:00
verify_cpu.S
vm86_32.c	x86/asm/entry: Rename 'init_tss' to 'cpu_tss'	2015-03-06 08:32:58 +01:00
vmlinux.lds.S	x86-64: Use RIP-relative addressing for most per-CPU accesses	2014-11-04 20:43:14 +01:00
vsmp_64.c	x86: replace __init_or_module with __init in non-modular vsmp_64.c	2015-06-16 14:12:41 -04:00
x86_init.c	PCI changes for the v4.2 merge window:	2015-06-23 13:41:24 -07:00
x8664_ksyms_64.c	preempt: Use preempt_schedule_context() as the official tracing preemption point	2015-06-07 15:57:42 +02:00