linux-stable/arch/x86/kernel
Steven Rostedt (Red Hat) 2b4bc78956 trace,x86: Do not call local_irq_save() in load_current_idt()
As load_current_idt() is now what is used to update the IDT for the
switches needed for NMI, lockdep debug, and for tracing, it must not
call local_irq_save(). This is because one of the users of this is
lockdep, which does tracing of local_irq_save() and when the debug
trap is hit, we need to update the IDT before tracing interrupts
being disabled. As load_current_idt() is used to do this, calling
local_irq_save() which lockdep traces, defeats the point of calling
load_current_idt().

As interrupts are already disabled when used by lockdep and NMI, the
only other user is tracing that can disable interrupts itself. Simply
have the tracing update disable interrupts before calling load_current_idt()
instead of breaking the other users.

Here's the dump that happened:

------------[ cut here ]------------
WARNING: at /work/autotest/nobackup/linux-test.git/kernel/fork.c:1196 copy_process+0x2c3/0x1398()
DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled)
Modules linked in:
CPU: 1 PID: 4570 Comm: gdm-simple-gree Not tainted 3.10.0-rc3-test+ #5
Hardware name:                  /DG965MQ, BIOS MQ96510J.86A.0372.2006.0605.1717 06/05/2006
 ffffffff81d2a7a5 ffff88006ed13d50 ffffffff8192822b ffff88006ed13d90
 ffffffff81035f25 ffff8800721c6000 ffff88006ed13da0 0000000001200011
 0000000000000000 ffff88006ed5e000 ffff8800721c6000 ffff88006ed13df0
Call Trace:
 [<ffffffff8192822b>] dump_stack+0x19/0x1b
 [<ffffffff81035f25>] warn_slowpath_common+0x67/0x80
 [<ffffffff81035fe1>] warn_slowpath_fmt+0x46/0x48
 [<ffffffff812bfc5d>] ? __raw_spin_lock_init+0x31/0x52
 [<ffffffff810341f7>] copy_process+0x2c3/0x1398
 [<ffffffff8103539d>] do_fork+0xa8/0x260
 [<ffffffff810ca7b1>] ? trace_preempt_on+0x2a/0x2f
 [<ffffffff812afb3e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
 [<ffffffff81937fe7>] ? sysret_check+0x1b/0x56
 [<ffffffff81937fe7>] ? sysret_check+0x1b/0x56
 [<ffffffff810355cf>] SyS_clone+0x16/0x18
 [<ffffffff81938369>] stub_clone+0x69/0x90
 [<ffffffff81937fc2>] ? system_call_fastpath+0x16/0x1b
---[ end trace 8b157a9d20ca1aa2 ]---

in fork.c:

 #ifdef CONFIG_PROVE_LOCKING
	DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled); <-- bug here
	DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
 #endif

Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-06-22 13:16:19 -04:00
..
acpi Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-04-30 08:41:21 -07:00
apic trace,x86: Move creation of irq tracepoints from apic.c to irq.c 2013-06-21 10:33:28 -04:00
cpu x86, trace: Add irq vector tracepoints 2013-06-20 22:25:34 -07:00
kprobes kprobes/x86: Just return error for sanity check failure instead of using BUG_ON 2013-04-08 17:28:34 +02:00
.gitignore
alternative.c x86, cpu: Expand cpufeature facility to include cpu bugs 2013-04-02 10:12:52 -07:00
amd_gart_64.c x86, mm: use pfn_range_is_mapped() with gart 2012-11-17 11:59:10 -08:00
amd_nb.c Merge branch 'x86-ras-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-04-30 08:42:45 -07:00
apb_timer.c Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-02-19 20:11:07 -08:00
aperture_64.c x86/mm/gart: Drop unnecessary check 2013-04-16 10:54:40 +02:00
apm_32.c cpuidle: remove en_core_tk_irqen flag 2013-04-23 13:45:22 +02:00
asm-offsets.c x86, um/x86: switch to generic sys_execve and kernel_execve 2012-09-30 22:53:32 -04:00
asm-offsets_32.c x86, gdt, hibernate: Store/load GDT for hibernate path. 2013-05-02 11:27:35 -07:00
asm-offsets_64.c x86, gdt, hibernate: Store/load GDT for hibernate path. 2013-05-02 11:27:35 -07:00
audit_64.c
bootflag.c
check.c x86: kernel/check.c simple_strtoul cleanup 2012-05-15 15:36:41 -07:00
cpuid.c new helper: file_inode(file) 2013-02-22 23:31:31 -05:00
crash.c x86/kexec: crash_vmclear_local_vmcss needs __rcu 2012-12-11 19:55:23 -02:00
crash_dump_32.c
crash_dump_64.c
devicetree.c x86: dt: Use linear irq domain for ioapic(s) 2012-08-21 22:16:57 +02:00
doublefault_32.c x86, xen, gdt: Remove the pvops variant of store_gdt. 2013-04-11 15:40:38 -07:00
dumpstack.c dump_stack: consolidate dump_stack() implementations and unify their behaviors 2013-04-30 17:04:02 -07:00
dumpstack_32.c dump_stack: unify debug information printed by show_regs() 2013-04-30 17:04:02 -07:00
dumpstack_64.c dump_stack: unify debug information printed by show_regs() 2013-04-30 17:04:02 -07:00
e820.c x86, mm: Let "memmap=" take more entries one time 2012-11-17 11:59:51 -08:00
early-quirks.c iommu/vt-d: add quirk for broken interrupt remapping on 55XX chipsets 2013-04-18 17:00:47 +02:00
early_printk.c early_printk: consolidate random copies of identical code 2013-04-29 18:28:13 -07:00
entry_32.S x86, trace: Add irq vector tracepoints 2013-06-20 22:25:34 -07:00
entry_64.S x86, trace: Add irq vector tracepoints 2013-06-20 22:25:34 -07:00
ftrace.c x86/ftrace: Use __pa_symbol instead of __pa on C visible symbols 2012-11-16 16:42:09 -08:00
head.c x86: Make sure we can boot in the case the BDA contains pure garbage 2013-02-27 13:38:57 -08:00
head32.c x86: Merge early kernel reserve for 32bit and 64bit 2013-01-29 19:32:58 -08:00
head64.c x86: Fix bit corruption at CPU resume time 2013-05-20 11:36:03 -07:00
head_32.S Merge branch 'x86/microcode' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-02-22 19:22:52 -08:00
head_64.S x86, trace: Add irq vector tracepoints 2013-06-20 22:25:34 -07:00
hpet.c x86, hpet: Introduce x86_msi_ops.setup_hpet_msi 2013-01-28 10:48:30 +01:00
hw_breakpoint.c
i386_ksyms_32.c x86-32: Add support for 64bit get_user() 2013-02-07 15:07:28 -08:00
i387.c x86: Allow FPU to be used at interrupt time even with eagerfpu 2013-05-30 16:36:42 -07:00
i8237.c
i8253.c
i8259.c x86/irq/i8259: Fix incorrect comment 2012-08-22 09:34:24 +02:00
io_delay.c
ioport.c x86: get rid of pt_regs argument of iopl(2) 2013-02-03 18:16:24 -05:00
irq.c trace,x86: Move creation of irq tracepoints from apic.c to irq.c 2013-06-21 10:33:28 -04:00
irq_32.c
irq_64.c
irq_work.c x86, trace: Add irq vector tracepoints 2013-06-20 22:25:34 -07:00
irqinit.c KVM: VMX: Register a new IPI for posted interrupt 2013-04-16 16:32:39 -03:00
jump_label.c
kdebugfs.c arch/x86/kernel/kdebugfs.c: Ensure a consistent return value in error case 2012-07-26 15:07:20 +02:00
kgdb.c kgdb,x86: fix warning about unused variable 2012-10-12 06:37:34 -05:00
kvm.c context_tracking: Restore correct previous context state on exception exit 2013-03-07 17:10:11 +01:00
kvmclock.c Merge branch 'master' into queue 2013-03-04 20:10:32 -03:00
ldt.c
machine_kexec_32.c
machine_kexec_64.c x86, kexec, 64bit: Only set ident mapping for ram. 2013-01-29 15:26:35 -08:00
Makefile trace,x86: Move creation of irq tracepoints from apic.c to irq.c 2013-06-21 10:33:28 -04:00
microcode_amd.c x86, microcode, AMD: Add support for family 16h processors 2012-11-20 22:23:28 -08:00
microcode_core.c x86/microcode_intel.h: Define functions and macros for early loading ucode 2013-01-31 13:18:50 -08:00
microcode_core_early.c x86, microcode: Verify the family before dispatching microcode patching 2013-04-19 16:36:03 -07:00
microcode_intel.c x86/microcode_intel.h: Define functions and macros for early loading ucode 2013-01-31 13:18:50 -08:00
microcode_intel_early.c x86/microcode: Add local mutex to fix physical CPU hot-add deadlock 2013-05-09 11:10:00 +02:00
microcode_intel_lib.c x86/microcode_intel_lib.c: Early update ucode on Intel's CPU 2013-01-31 13:19:14 -08:00
mmconf-fam10h_64.c
module.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2012-07-24 13:34:56 -07:00
mpparse.c Merge branch 'x86-trampoline-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-29 20:14:53 -07:00
msr.c more file_inode() open-coded instances 2013-02-27 16:59:05 -05:00
nmi.c x86/nmi: export local_touch_nmi() symbol for modules 2013-01-17 22:25:57 +08:00
nmi_selftest.c x86/nmi: Clean up register_nmi_handler() usage 2012-06-20 14:23:17 +02:00
paravirt-spinlocks.c
paravirt.c Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-04-30 08:41:21 -07:00
paravirt_patch_32.c
paravirt_patch_64.c
pci-calgary_64.c x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level> 2012-06-06 09:17:22 +02:00
pci-dma.c x86/dma-debug: Bump PREALLOC_DMA_DEBUG_ENTRIES 2013-01-24 17:34:18 +01:00
pci-iommu_table.c
pci-nommu.c X86: integrate CMA with DMA-mapping subsystem 2012-05-21 15:09:38 +02:00
pci-swiotlb.c
pcspeaker.c
perf_regs.c perf: Fix off by one test in perf_reg_value() 2012-09-19 17:08:40 +02:00
probe_roms.c x86/pci/probe_roms: Add missing __iomem annotation to pci_map_biosrom() 2012-09-05 10:52:25 +02:00
process.c x86: Fix idle consolidation fallout 2013-05-07 16:24:03 +02:00
process_32.c dump_stack: unify debug information printed by show_regs() 2013-04-30 17:04:02 -07:00
process_64.c dump_stack: unify debug information printed by show_regs() 2013-04-30 17:04:02 -07:00
ptrace.c x86: ptrace.c only needs export.h and not the full module.h 2013-02-14 12:56:12 -08:00
pvclock.c x86/kvm: Fix pvclock vsyscall fixmap 2013-02-28 08:50:11 +02:00
quirks.c x86, quirks: Shut-up a long-standing gcc warning 2013-04-02 16:03:34 -07:00
reboot.c efi: Make 'efi_enabled' a function to query EFI facilities 2013-01-30 11:51:59 -08:00
reboot_fixups_32.c
relocate_kernel_32.S
relocate_kernel_64.S x86: Fix typo in kexec register clearing 2013-06-12 15:16:18 -07:00
resource.c
rtc.c x86: Do full rtc synchronization with ntp 2013-03-15 16:50:26 -07:00
setup.c dump_stack: implement arch-specific hardware description in task dumps 2013-04-30 17:04:02 -07:00
setup_percpu.c x86: Add read_mostly declaration/definition to variables from smp.h 2012-06-14 12:42:11 +02:00
signal.c x86: convert to ksignal 2013-02-14 09:21:17 -05:00
smp.c x86, trace: Add irq vector tracepoints 2013-06-20 22:25:34 -07:00
smpboot.c x86: Use generic idle loop 2013-04-08 17:39:29 +02:00
stacktrace.c
step.c ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL 2013-01-22 10:08:00 -08:00
sys_x86_64.c x86: Fix a typo 2013-01-24 16:22:10 +01:00
syscall_32.c
syscall_64.c
tboot.c Revert "x86-64/efi: Use EFI to deal with platform wall clock (again)" 2012-12-15 15:20:41 -08:00
tce_64.c
test_nx.c
test_rodata.c
time.c MCA: delete all remaining traces of microchannel bus support. 2012-05-17 19:06:13 -04:00
tls.c make SYSCALL_DEFINE<n>-generated wrappers do asmlinkage_protect 2013-03-03 22:58:33 -05:00
tls.h
topology.c x86, topology: Debug CPU0 hotplug 2012-11-14 15:28:11 -08:00
trace_clock.c tracing,x86: Add a TSC trace_clock 2012-11-13 15:48:27 -05:00
tracepoint.c trace,x86: Do not call local_irq_save() in load_current_idt() 2013-06-22 13:16:19 -04:00
traps.c x86: Rename variables for debugging 2013-06-20 22:25:13 -07:00
tsc.c x86: tsc: Add support for new S3_NONSTOP feature 2013-03-15 16:51:18 -07:00
tsc_sync.c
uprobes.c uretprobes/x86: Hijack return address 2013-04-13 15:31:55 +02:00
verify_cpu.S
vm86_32.c x86, vm86: fix VM86 syscalls: use SYSCALL_DEFINEx(...) 2013-05-02 20:36:32 -04:00
vmlinux.lds.S x86: Drop always empty .text..page_aligned section 2013-03-11 15:07:56 +01:00
vsmp_64.c x86/apic/x2apic: Limit the vector reservation to the user specified mask 2012-07-06 11:00:22 +02:00
vsyscall_64.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-12-16 15:40:50 -08:00
vsyscall_emu_64.S
vsyscall_trace.h
x86_init.c Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-02-21 18:06:55 -08:00
x8664_ksyms_64.c x86: Improve __phys_addr performance by making use of carry flags and inlining 2012-11-16 16:42:08 -08:00
xsave.c x86, smap: Do not abuse the [f][x]rstor_checking() functions for user space 2012-09-25 15:42:18 -07:00