linux/arch/x86/kernel
Matt Fleming 47997d756a x86/rtc: Don't recursively acquire rtc_lock
A deadlock was introduced on x86 in commit ef68c8f87e ("x86:
Serialize EFI time accesses on rtc_lock") because efi_get_time()
and friends can be called with rtc_lock already held by
read_persistent_time(), e.g.:

 timekeeping_init()
    read_persistent_clock()     <-- acquire rtc_lock
        efi_get_time()
            phys_efi_get_time() <-- acquire rtc_lock <DEADLOCK>

To fix this let's push the locking down into the get_wallclock()
and set_wallclock() implementations.  Only the clock
implementations that access the x86 RTC directly need to acquire
rtc_lock, so it makes sense to push the locking down into the
rtc, vrtc and efi code.

The virtualization implementations don't require rtc_lock to be
held because they provide their own serialization.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Acked-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Avi Kivity <avi@redhat.com> [for the virtualization aspect]
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-21 16:16:09 +02:00
..
acpi x86 idle: move mwait_idle_with_hints() to where it is used 2011-08-03 19:06:36 -04:00
apic x86, UV: Remove UV delay in starting slave cpus 2011-08-05 23:48:34 +02:00
cpu x86, perf: Check that current->mm is alive before getting user callchain 2011-08-31 15:56:31 +02:00
.gitignore
alternative.c x86-64: Move vread_tsc and vread_hpet into the vDSO 2011-07-14 17:57:05 -07:00
amd_gart_64.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
amd_nb.c x86, amd-nb: Rename CPU PCI id define for F4 2011-03-31 08:51:38 +02:00
apb_timer.c Merge branch 'timers-clocksource-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2011-07-23 10:34:47 -07:00
aperture_64.c x86, gart: Don't enforce GART aperture lower-bound by alignment 2011-04-18 10:31:38 -07:00
apm_32.c i8253: Cleanup outb/inb magic 2011-07-01 10:37:15 +02:00
asm-offsets_32.c lguest: use a special 1:1 linear pagetable mode until first switch. 2011-07-22 14:39:48 +09:30
asm-offsets_64.c x86: Partly unify asm-offsets_{32,64}.c 2011-02-10 13:31:37 +01:00
asm-offsets.c x86, asm: Cleanup unnecssary macros in asm-offsets.c 2011-02-25 16:37:32 -08:00
audit_64.c
bootflag.c
check.c x86: Don't check for BIOS corruption in first 64K when there's no need to 2011-03-09 16:36:41 +01:00
cpuid.c
crash_dump_32.c crash_dump: export is_kdump_kernel to modules, consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn 2011-03-23 19:47:19 -07:00
crash_dump_64.c crash_dump: export is_kdump_kernel to modules, consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn 2011-03-23 19:47:19 -07:00
crash.c
devicetree.c Merge branch 'of-pci' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-22 14:54:02 -07:00
doublefault_32.c
dumpstack_32.c x86, dumpstack: Correct stack dump info when frame pointer is available 2011-03-18 10:51:42 +01:00
dumpstack_64.c x86: Don't use frame pointer to save old stack on irq entry 2011-07-02 18:06:36 +02:00
dumpstack.c Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6 2011-05-19 18:24:11 -07:00
e820.c crash_dump: export is_kdump_kernel to modules, consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn 2011-03-23 19:47:19 -07:00
early_printk.c
early-quirks.c x86, quirk: Fix SB600 revision check 2011-03-16 14:03:32 +01:00
entry_32.S x86-32: Fix boot with CONFIG_X86_INVD_BUG 2011-08-25 13:27:14 -07:00
entry_64.S Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-tip 2011-08-12 20:46:24 -07:00
ftrace.c x86/ftrace: Fix compiler warning in ftrace.c 2011-05-25 19:56:26 -04:00
head32.c Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2011-05-19 18:08:06 -07:00
head64.c x86: Cleanup highmap after brk is concluded 2011-03-19 11:58:19 -07:00
head_32.S Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2011-03-15 20:01:36 -07:00
head_64.S x86, trampoline: Common infrastructure for low memory trampolines 2011-02-17 21:02:43 -08:00
head.c
hpet.c Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2011-07-22 17:05:15 -07:00
hw_breakpoint.c
i386_ksyms_32.c
i387.c treewide: fix potentially dangerous trailing ';' in #defined values/expressions 2011-07-21 14:10:00 +02:00
i8237.c x86: Use syscore_ops instead of sysdev classes and sysdevs 2011-03-23 22:15:54 +01:00
i8253.c x86: Use common i8253 clockevent 2011-07-01 10:37:14 +02:00
i8259.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
init_task.c
io_delay.c
ioport.c x86: Use bitmap library functions 2011-02-17 14:59:22 +01:00
irq_32.c x86: Fix common misspellings 2011-03-18 10:39:30 +01:00
irq_64.c
irq_work.c
irq.c x86: Don't unmask disabled irqs when migrating them 2011-05-19 14:51:08 +02:00
irqinit.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
jump_label.c x86, cpu: Clean up and unify the NOP selection infrastructure 2011-04-18 16:40:21 -07:00
kdebugfs.c
kgdb.c perf: Add context field to perf_event 2011-07-01 11:06:38 +02:00
kprobes.c kprobes, x86: Disable irqs during optimized callback 2011-05-11 13:21:23 +02:00
kvm.c KVM guest: KVM Steal time registration 2011-07-24 11:49:36 +03:00
kvmclock.c KVM guest: KVM Steal time registration 2011-07-24 11:49:36 +03:00
ldt.c
machine_kexec_32.c
machine_kexec_64.c
Makefile Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-tip 2011-08-12 20:46:24 -07:00
mca_32.c x86: Fix common misspellings 2011-03-18 10:39:30 +01:00
microcode_amd.c x86, microcode, AMD: Fix section header size check 2011-06-16 17:23:54 +02:00
microcode_core.c x86, microcode: Unregister syscore_ops after microcode unloaded 2011-03-29 11:12:04 +02:00
microcode_intel.c
mmconf-fam10h_64.c
module.c modules: make arch's use default loader hooks 2011-07-24 22:06:04 +09:30
mpparse.c x86, ioapic: Consolidate mp_ioapics[] into 'struct ioapic' 2011-05-20 13:40:59 +02:00
msr.c
paravirt_patch_32.c
paravirt_patch_64.c
paravirt-spinlocks.c
paravirt.c Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-tip 2011-08-12 20:46:24 -07:00
pci-calgary_64.c treewide: Convert uses of struct resource to resource_size(ptr) 2011-06-10 14:55:36 +02:00
pci-dma.c x86/PCI: Remove dma32_reserve_bootmem 2011-05-10 15:43:32 -07:00
pci-iommu_table.c arch/x86/kernel/pci-iommu_table.c: Convert sprintf_symbol to %pS 2011-05-10 10:21:35 +02:00
pci-nommu.c
pci-swiotlb.c
pcspeaker.c
probe_roms.c treewide: Convert uses of struct resource to resource_size(ptr) 2011-06-10 14:55:36 +02:00
process_32.c cpuidle: stop depending on pm_idle 2011-08-03 19:06:37 -04:00
process_64.c cpuidle: stop depending on pm_idle 2011-08-03 19:06:37 -04:00
process.c x86 idle: move mwait_idle_with_hints() to where it is used 2011-08-03 19:06:36 -04:00
ptrace.c perf: Add context field to perf_event 2011-07-01 11:06:38 +02:00
pvclock.c
quirks.c x86, quirks: Use pci_dev->revision 2011-07-21 10:26:00 +02:00
reboot_32.S x86, reboot: Fix relocations in reboot_32.S 2011-05-02 14:44:46 -07:00
reboot_fixups_32.c
reboot.c x86: Make Dell Latitude E6420 use reboot=pci 2011-07-21 11:47:17 -07:00
relocate_kernel_32.S kexec, x86: Fix incorrect jump back address if not preserving context 2011-07-21 11:19:28 +02:00
relocate_kernel_64.S kexec, x86: Fix incorrect jump back address if not preserving context 2011-07-21 11:19:28 +02:00
resource.c
rtc.c x86/rtc: Don't recursively acquire rtc_lock 2011-09-21 16:16:09 +02:00
setup_percpu.c
setup.c Merge branch 'linus' into x86/urgent 2011-05-26 13:51:35 +02:00
signal.c x86: Kill handle_signal()->set_fs() 2011-07-14 21:46:20 -07:00
smp.c sched: Provide scheduler_ipi() callback in response to smp_send_reschedule() 2011-04-14 08:52:32 +02:00
smpboot.c Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2011-07-22 17:02:38 -07:00
stacktrace.c x86: Swap save_stack_trace_regs parameters 2011-06-14 22:48:51 -04:00
step.c x86-64: Add user_64bit_mode paravirt op 2011-08-04 16:13:49 -07:00
sys_i386_32.c
sys_x86_64.c
syscall_64.c
syscall_table_32.S All Arch: remove linkage for sys_nfsservctl system call 2011-08-26 15:09:58 -07:00
tboot.c net: remove mm.h inclusion from netdevice.h 2011-06-21 19:17:20 -07:00
tce_64.c
test_nx.c x86: Eliminate various 'set but not used' warnings 2011-05-21 19:10:33 +02:00
test_rodata.c
time.c i8253: Create linux/i8253.h and use it in all 8253 related files 2011-06-09 15:01:37 +02:00
tls.c
tls.h
topology.c x86: Fix common misspellings 2011-03-18 10:39:30 +01:00
trampoline_32.S x86, trampoline: Common infrastructure for low memory trampolines 2011-02-17 21:02:43 -08:00
trampoline_64.S x86-64, trampoline: Remove unused variable 2011-02-18 15:50:36 -08:00
trampoline.c x86, trampoline: Common infrastructure for low memory trampolines 2011-02-17 21:02:43 -08:00
traps.c Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-tip 2011-08-12 20:46:24 -07:00
tsc_sync.c
tsc.c Merge branches 'x86-detect-hyper-for-linus', 'x86-fpu-for-linus', 'x86-kexec-for-linus', 'x86-platform-for-linus', 'x86-quirks-for-linus', 'x86-tsc-for-linus' and 'x86-smpboot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2011-07-23 10:38:21 -07:00
verify_cpu.S x86: Fix common misspellings 2011-03-18 10:39:30 +01:00
vm86_32.c
vmlinux.lds.S x86-64: Rework vsyscall emulation and add vsyscall= parameter 2011-08-10 19:26:46 -05:00
vsmp_64.c
vsyscall_64.c x86-64: Rework vsyscall emulation and add vsyscall= parameter 2011-08-10 19:26:46 -05:00
vsyscall_emu_64.S x86-64: Rework vsyscall emulation and add vsyscall= parameter 2011-08-10 19:26:46 -05:00
vsyscall_trace.h x86-64: Add vsyscall:emulate_vsyscall trace event 2011-08-04 16:13:53 -07:00
x86_init.c Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2011-05-19 18:08:06 -07:00
x8664_ksyms_64.c
xsave.c x86: Fix common misspellings 2011-03-18 10:39:30 +01:00