Reinette Chatre 93e2d845f2 x86/intel_rdt: Fix potential deadlock during resctrl unmount ... [ Upstream commit 36b6f9fcb8 ] Lockdep warns about a potential deadlock: [ 66.782842] ====================================================== [ 66.782888] WARNING: possible circular locking dependency detected [ 66.782937] 4.14.0-rc2-test-test+ #48 Not tainted [ 66.782983] ------------------------------------------------------ [ 66.783052] umount/336 is trying to acquire lock: [ 66.783117] (cpu_hotplug_lock.rw_sem){++++}, at: [<ffffffff81032395>] rdt_kill_sb+0x215/0x390 [ 66.783193] but task is already holding lock: [ 66.783244] (rdtgroup_mutex){+.+.}, at: [<ffffffff810321b6>] rdt_kill_sb+0x36/0x390 [ 66.783305] which lock already depends on the new lock. [ 66.783364] the existing dependency chain (in reverse order) is: [ 66.783419] -> #3 (rdtgroup_mutex){+.+.}: [ 66.783467] __lock_acquire+0x1293/0x13f0 [ 66.783509] lock_acquire+0xaf/0x220 [ 66.783543] __mutex_lock+0x71/0x9b0 [ 66.783575] mutex_lock_nested+0x1b/0x20 [ 66.783610] intel_rdt_online_cpu+0x3b/0x430 [ 66.783649] cpuhp_invoke_callback+0xab/0x8e0 [ 66.783687] cpuhp_thread_fun+0x7a/0x150 [ 66.783722] smpboot_thread_fn+0x1cc/0x270 [ 66.783764] kthread+0x16e/0x190 [ 66.783794] ret_from_fork+0x27/0x40 [ 66.783825] -> #2 (cpuhp_state){+.+.}: [ 66.783870] __lock_acquire+0x1293/0x13f0 [ 66.783906] lock_acquire+0xaf/0x220 [ 66.783938] cpuhp_issue_call+0x102/0x170 [ 66.783974] __cpuhp_setup_state_cpuslocked+0x154/0x2a0 [ 66.784023] __cpuhp_setup_state+0xc7/0x170 [ 66.784061] page_writeback_init+0x43/0x67 [ 66.784097] pagecache_init+0x43/0x4a [ 66.784131] start_kernel+0x3ad/0x3f7 [ 66.784165] x86_64_start_reservations+0x2a/0x2c [ 66.784204] x86_64_start_kernel+0x72/0x75 [ 66.784241] verify_cpu+0x0/0xfb [ 66.784270] -> #1 (cpuhp_state_mutex){+.+.}: [ 66.784319] __lock_acquire+0x1293/0x13f0 [ 66.784355] lock_acquire+0xaf/0x220 [ 66.784387] __mutex_lock+0x71/0x9b0 [ 66.784419] mutex_lock_nested+0x1b/0x20 [ 66.784454] __cpuhp_setup_state_cpuslocked+0x52/0x2a0 [ 66.784497] __cpuhp_setup_state+0xc7/0x170 [ 66.784535] page_alloc_init+0x28/0x30 [ 66.784569] start_kernel+0x148/0x3f7 [ 66.784602] x86_64_start_reservations+0x2a/0x2c [ 66.784642] x86_64_start_kernel+0x72/0x75 [ 66.784678] verify_cpu+0x0/0xfb [ 66.784707] -> #0 (cpu_hotplug_lock.rw_sem){++++}: [ 66.784759] check_prev_add+0x32f/0x6e0 [ 66.784794] __lock_acquire+0x1293/0x13f0 [ 66.784830] lock_acquire+0xaf/0x220 [ 66.784863] cpus_read_lock+0x3d/0xb0 [ 66.784896] rdt_kill_sb+0x215/0x390 [ 66.784930] deactivate_locked_super+0x3e/0x70 [ 66.784968] deactivate_super+0x40/0x60 [ 66.785003] cleanup_mnt+0x3f/0x80 [ 66.785034] __cleanup_mnt+0x12/0x20 [ 66.785070] task_work_run+0x8b/0xc0 [ 66.785103] exit_to_usermode_loop+0x94/0xa0 [ 66.786804] syscall_return_slowpath+0xe8/0x150 [ 66.788502] entry_SYSCALL_64_fastpath+0xab/0xad [ 66.790194] other info that might help us debug this: [ 66.795139] Chain exists of: cpu_hotplug_lock.rw_sem --> cpuhp_state --> rdtgroup_mutex [ 66.800035] Possible unsafe locking scenario: [ 66.803267] CPU0 CPU1 [ 66.804867] ---- ---- [ 66.806443] lock(rdtgroup_mutex); [ 66.808002] lock(cpuhp_state); [ 66.809565] lock(rdtgroup_mutex); [ 66.811110] lock(cpu_hotplug_lock.rw_sem); [ 66.812608] *** DEADLOCK *** [ 66.816983] 2 locks held by umount/336: [ 66.818418] #0: (&type->s_umount_key#35){+.+.}, at: [<ffffffff81229738>] deactivate_super+0x38/0x60 [ 66.819922] #1: (rdtgroup_mutex){+.+.}, at: [<ffffffff810321b6>] rdt_kill_sb+0x36/0x390 When the resctrl filesystem is unmounted the locks should be obtain in the locks in the same order as was done when the cpus came online: cpu_hotplug_lock before rdtgroup_mutex. This also requires to switch the static_branch_disable() calls to the _cpulocked variant because now cpu hotplug lock is held already. [ tglx: Switched to cpus_read_[un]lock ] Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Acked-by: Vikas Shivappa <vikas.shivappa@linux.intel.com> Acked-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/cc292e76be073f7260604651711c47b09fd0dc81.1508490116.git.reinette.chatre@intel.com Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2017-12-17 15:08:01 +01:00
..
acpi	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
apic	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
cpu	x86/intel_rdt: Fix potential deadlock during resctrl unmount	2017-12-17 15:08:01 +01:00
fpu	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
kprobes	kprobes/x86: Disable preemption in ftrace-based jprobes	2017-12-10 13:40:42 +01:00
.gitignore
alternative.c	x86: Clarify/fix no-op barriers for text_poke_bp()	2017-08-10 17:35:19 +02:00
amd_gart_64.c	x86: remove arch specific dma_supported implementation	2017-06-28 06:54:46 -07:00
amd_nb.c	x86/cpu/AMD: Apply the Erratum 688 fix when the BIOS doesn't	2017-10-22 13:06:02 +02:00
apb_timer.c	Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-12-25 14:30:04 -08:00
aperture_64.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
apm_32.c	dmi: Mark all struct dmi_system_id instances const	2017-09-14 11:59:30 +02:00
asm-offsets.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
asm-offsets_32.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
asm-offsets_64.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
audit_64.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
bootflag.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
check.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
cpuid.c	Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-12-12 19:25:04 -08:00
crash.c	kexec: move vmcoreinfo out of the kernel's .bss section	2017-07-12 16:25:59 -07:00
crash_dump_32.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
crash_dump_64.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
devicetree.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
doublefault.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
dumpstack.c	x86/asm/32: Remove a bunch of '& 0xffff' from pt_regs segment reads	2017-07-30 12:04:41 +02:00
dumpstack_32.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
dumpstack_64.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
e820.c	x86/boot/e820: Add support to determine the E820 type of an address	2017-07-18 11:38:01 +02:00
early-quirks.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
early_printk.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
ebda.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
eisa.c	x86/eisa: Add missing include	2017-08-31 21:34:48 +02:00
espfix_64.c	x86/mm: Provide general kernel support for memory encryption	2017-07-18 11:38:00 +02:00
ftrace.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
ftrace_32.S	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
ftrace_64.S	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
head32.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
head64.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
head_32.S	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
head_64.S	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
hpet.c	x86/hpet: Cure interface abuse in the resume path	2017-08-01 13:02:37 +02:00
hw_breakpoint.c
i8237.c
i8253.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
i8259.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
idt.c	x86/idt: Remove X86_TRAP_BP initialization in idt_setup_traps()	2017-11-08 21:05:23 +01:00
io_delay.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
ioport.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
irq.c	x86/ipi: Make platform IPI depend on APIC	2017-08-29 11:42:29 +02:00
irq_32.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
irq_64.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
irq_work.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
irqinit.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
itmt.c	sched/x86: Remove unnecessary TBM3 check to update topology	2017-01-19 08:42:37 +01:00
jump_label.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
kdebugfs.c	x86, mpparse, x86/acpi, x86/PCI, x86/dmi, SFI: Use memremap() for RAM mappings	2017-07-18 11:37:58 +02:00
kexec-bzimage64.c	x86/boot/e820: Rename the e820_table_firmware to e820_table_kexec	2017-07-05 10:09:02 +02:00
kgdb.c
ksysfs.c	x86/sysfs: Fix off-by-one error in loop termination	2017-09-25 09:36:16 +02:00
kvm.c	kvm/x86: Avoid async PF preempting the kernel incorrectly	2017-10-04 18:28:53 +02:00
kvmclock.c	kvm: Return -ENODEV from update_persistent_clock	2017-11-02 18:23:18 +01:00
ldt.c	x86/entry: Use SYSCALL_DEFINE() macros for sys_modify_ldt()	2017-12-10 13:40:41 +01:00
livepatch.c
machine_kexec_32.c	x86/idt: Consolidate IDT invalidation	2017-08-29 12:07:26 +02:00
machine_kexec_64.c	x86/mm, kexec: Fix memory corruption with SME on successive kexecs	2017-07-30 12:09:12 +02:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
mmconf-fam10h_64.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
module.c	x86/module: Detect and skip invalid relocations	2017-11-05 09:52:16 +01:00
mpparse.c	x86/boot: Fix boot failure when SMP MP-table is based at 0	2017-11-30 08:40:39 +00:00
msr.c	x86/msr: Remove bogus cleanup from the error path	2016-12-25 10:47:41 +01:00
nmi.c	x86/nmi: Use raw lock	2017-08-16 20:40:09 +02:00
nmi_selftest.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
paravirt-spinlocks.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
paravirt.c	x86/paravirt: Remove no longer used paravirt functions	2017-09-13 10:55:15 +02:00
paravirt_patch_32.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
paravirt_patch_64.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
pci-calgary_64.c	x86: remove arch specific dma_supported implementation	2017-06-28 06:54:46 -07:00
pci-dma.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
pci-iommu_table.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
pci-nommu.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
pci-swiotlb.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
pcspeaker.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
perf_regs.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
platform-quirks.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
pmem.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
probe_roms.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
process.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
process_32.c	Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-09-04 13:56:37 -07:00
process_64.c	Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-09-04 13:56:37 -07:00
ptrace.c	x86/arch_prctl/64: Rename do_arch_prctl() to do_arch_prctl_64()	2017-03-20 16:10:32 +01:00
pvclock.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/nmi.h>	2017-03-02 08:42:30 +01:00
quirks.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
reboot.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
reboot_fixups_32.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
relocate_kernel_32.S
relocate_kernel_64.S	x86/mm, kexec: Fix memory corruption with SME on successive kexecs	2017-07-30 12:09:12 +02:00
resource.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
rtc.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
setup.c	x86/mm/64: Initialize CR4.PCIDE early	2017-09-13 09:54:43 +02:00
setup_percpu.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
signal.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
signal_compat.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
smp.c	x86/tracing: Disentangle pagefault and resched IPI tracing key	2017-08-29 11:42:29 +02:00
smpboot.c	x86/idt: Load idt early in start_secondary	2017-12-14 09:52:53 +01:00
stacktrace.c	stacktrace/x86: add function for detecting reliable stack traces	2017-03-08 09:18:02 +01:00
step.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
sys_x86_64.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
sysfb.c
sysfb_efi.c
sysfb_simplefb.c
tboot.c	iommu/vt-d: Correctly disable Intel IOMMU force on	2017-06-15 16:41:10 +02:00
tce_64.c
time.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
tls.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
tls.h
topology.c
trace_clock.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
tracepoint.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
traps.c	x86/debug: Handle warnings before the notifier chain, to fix KGDB crash	2017-11-10 08:04:19 +01:00
tsc.c	x86/smpboot: Make optimization of delay calibration work correctly	2017-11-07 16:04:54 +01:00
tsc_msr.c
tsc_sync.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
unwind_frame.c	x86/unwind: Disable unwinder warnings on 32-bit	2017-10-10 12:49:49 +02:00
unwind_guess.c	x86/unwind: Add the ORC unwinder	2017-07-26 13:18:20 +02:00
unwind_orc.c	x86/unwind: Disable KASAN checking in the ORC unwinder	2017-11-08 10:21:49 +01:00
uprobes.c
verify_cpu.S
vm86_32.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
vmlinux.lds.S	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
vsmp_64.c
x86_init.c	x86/boot/e820: Rename default_machine_specific_memory_setup() to e820__memory_setup_default()	2017-01-28 14:42:26 +01:00