linux/arch/x86/kernel
Oleg Nesterov 43918f2bf4 signals: remove 'handler' parameter to tracehook functions
Container-init must behave like global-init to processes within the
container and hence it must be immune to unhandled fatal signals from
within the container (i.e SIG_DFL signals that terminate the process).

But the same container-init must behave like a normal process to processes
in ancestor namespaces and so if it receives the same fatal signal from a
process in ancestor namespace, the signal must be processed.

Implementing these semantics requires that send_signal() determine pid
namespace of the sender but since signals can originate from workqueues/
interrupt-handlers, determining pid namespace of sender may not always be
possible or safe.

This patchset implements the design/simplified semantics suggested by
Oleg Nesterov.  The simplified semantics for container-init are:

	- container-init must never be terminated by a signal from a
	  descendant process.

	- container-init must never be immune to SIGKILL from an ancestor
	  namespace (so a process in parent namespace must always be able
	  to terminate a descendant container).

	- container-init may be immune to unhandled fatal signals (like
	  SIGUSR1) even if they are from ancestor namespace. SIGKILL/SIGSTOP
	  are the only reliable signals to a container-init from ancestor
	  namespace.

This patch:

Based on an earlier patch submitted by Oleg Nesterov and comments from
Roland McGrath (http://lkml.org/lkml/2008/11/19/258).

The handler parameter is currently unused in the tracehook functions.
Besides, the tracehook functions are called with siglock held, so the
functions can check the handler if they later need to.

Removing the parameter simiplifies changes to sig_ignored() in a follow-on
patch.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:04:58 -07:00
..
acpi Merge branches 'x86/acpi', 'x86/apic', 'x86/asm', 'x86/cleanups', 'x86/mm', 'x86/signal' and 'x86/urgent'; commit 'v2.6.29-rc6' into x86/core 2009-02-24 21:50:43 +01:00
apic Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 2009-04-01 09:47:12 -07:00
cpu proc 2/2: remove struct proc_dir_entry::owner 2009-03-31 01:14:44 +04:00
.gitignore
Makefile Merge branch 'iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-03-30 13:41:00 -07:00
alternative.c Merge branch 'x86/core' into x86/mce2 2009-03-03 21:05:42 -08:00
amd_iommu.c Merge branch 'iommu/fixes-2.6.29' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/linux-2.6-iommu into core/iommu 2009-03-05 12:47:34 +01:00
amd_iommu_init.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/linux-2.6-iommu 2009-01-03 12:03:52 -08:00
aperture_64.c aperture_64.c: clarify that too small aperture is valid reason for this code 2008-11-28 15:24:39 +01:00
apm_32.c PM: Rework handling of interrupts during suspend-resume 2009-03-30 21:46:54 +02:00
asm-offsets.c
asm-offsets_32.c pm: rework includes, remove arch ifdefs 2009-04-01 08:59:16 -07:00
asm-offsets_64.c pm: rework includes, remove arch ifdefs 2009-04-01 08:59:16 -07:00
audit_64.c
bios_uv.c x86: bios_uv.c: uv_systab should be static 2008-12-29 22:08:28 -08:00
bootflag.c
check.c x86: fix 64k corruption-check 2009-03-15 07:03:15 +01:00
cpuid.c Merge branch 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-01-03 12:04:39 -08:00
crash.c x86, apic: remove duplicate asm/apic.h inclusions 2009-02-17 17:52:44 +01:00
crash_dump_32.c
crash_dump_64.c
doublefault_32.c
ds.c x86, pebs: correct qualifier passed to ds_write_config() from ds_request_pebs() 2009-03-06 16:13:15 +01:00
dumpstack.c Merge commit 'origin/master' into next 2009-03-30 14:04:53 +11:00
dumpstack.h ftrace: print real return in dumpstack for function graph 2008-12-03 08:56:25 +01:00
dumpstack_32.c ftrace: print real return in dumpstack for function graph 2008-12-03 08:56:25 +01:00
dumpstack_64.c x86-64: Move current task from PDA to per-cpu and consolidate with 32-bit. 2009-01-19 00:38:58 +09:00
e820.c x86: e820 fix various signedness issues in setup.c and e820.c 2009-03-23 15:02:05 +05:30
early-quirks.c x86: only scan the root bus in early PCI quirks 2009-01-09 12:46:22 -08:00
early_printk.c x86: properly __init-annotate recent early_printk additions 2009-03-13 02:37:18 +01:00
efi.c Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2 2009-03-27 17:28:43 +01:00
efi_32.c
efi_64.c Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2 2009-03-27 17:28:43 +01:00
efi_stub_32.S Merge branch 'x86/asm' into x86/mm 2009-02-25 08:27:46 +01:00
efi_stub_64.S x86: efi_stub_32,64 - add missing ENDPROCs 2009-02-24 18:08:40 +01:00
entry_32.S x86: entry_32.S fix compile warnings - fix work mask bit width 2009-03-14 09:42:51 +01:00
entry_64.S x86-64: move save_paranoid into .kprobes.text 2009-03-12 11:57:46 +01:00
ftrace.c tracing/function-graph-tracer: make arch generic push pop functions 2009-02-18 13:43:04 -05:00
geode_32.c
head.c x86, debug: remove EBDA debug printk 2008-12-12 11:08:42 +01:00
head32.c x86-32: use brk segment for allocating initial kernel pagetable 2009-03-14 17:23:47 -07:00
head64.c x86: add brk allocation for very, very early allocations 2009-03-14 15:37:14 -07:00
head_32.S x86-32: tighten the bound on additional memory to map 2009-03-17 11:52:10 -07:00
head_64.S x86: head_64.S - use IDT_ENTRIES instead of hardcoded number 2009-02-24 18:08:38 +01:00
hpet.c x86: hpet: stop HPET_COUNTER when programming periodic mode 2009-02-22 18:01:18 +01:00
i386_ksyms_32.c
i387.c x86, math-emu: fix init_fpu for task != current 2009-03-04 20:33:16 +01:00
i8237.c i8327: fix outb() parameter order 2009-02-10 13:13:23 +01:00
i8253.c x86: i8253 cleanup 2009-03-21 16:56:10 +05:30
i8259.c x86: refactor x86_quirks support 2009-02-23 00:08:11 +01:00
init_task.c take init_fs to saner place 2008-12-31 18:07:42 -05:00
io_delay.c x86: io_delay.c cleanup 2009-03-21 16:57:04 +05:30
ioport.c x86-32: use non-lazy io bitmap context switching 2009-03-02 12:07:48 +01:00
irq.c x86: irq.c keep CONFIG_X86_LOCAL_APIC interrupts together 2009-03-23 02:08:34 +05:30
irq_32.c Merge branch 'tj-percpu' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into core/percpu 2009-02-24 21:52:45 +01:00
irq_64.c x86: unify do_IRQ() 2009-02-09 12:16:05 +01:00
irqinit_32.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask 2009-03-30 18:00:26 -07:00
irqinit_64.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask 2009-03-30 18:00:26 -07:00
k8.c
kdebugfs.c x86: kdebugfs.c cleanup 2009-03-21 16:55:45 +05:30
kgdb.c x86, apic: remove genapic.h 2009-02-17 17:52:44 +01:00
kprobes.c x86: kprobes.c fix compilation warning 2009-03-18 13:21:01 +01:00
kvm.c x86: with the last user gone, remove set_pte_present 2009-03-19 14:04:19 +01:00
kvmclock.c x86: refactor x86_quirks support 2009-02-23 00:08:11 +01:00
ldt.c x86: ldt.c fix style problems 2009-01-02 17:46:24 +01:00
machine_kexec_32.c x86, kexec: fix kexec x86 coding style 2009-03-10 18:13:25 -07:00
machine_kexec_64.c x86, kexec: x86_64: add kexec jump support for x86_64 2009-03-10 18:13:25 -07:00
mca_32.c x86: refactor x86_quirks support 2009-02-23 00:08:11 +01:00
mfgpt_32.c cpumask: remove references to struct irqaction's mask field. 2009-03-30 22:05:14 +10:30
microcode_amd.c x86: fix warning in arch/x86/kernel/microcode_amd.c 2008-12-19 01:31:54 +01:00
microcode_core.c Merge branches 'x86/apic', 'x86/cleanups', 'x86/cpufeature', 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/detect-hyper', 'x86/doc', 'x86/dumpstack', 'x86/early-printk', 'x86/fpu', 'x86/idle', 'x86/io', 'x86/memory-corruption-check', 'x86/microcode', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/pat2', 'x86/pci-ioapic-boot-irq-quirks', 'x86/ptrace', 'x86/quirks', 'x86/reboot', 'x86/setup-memory', 'x86/signal', 'x86/sparse-fixes', 'x86/time', 'x86/uv' and 'x86/xen' into x86/core 2008-12-23 16:27:23 +01:00
microcode_intel.c x86: microcode_intel.c fix style problems 2009-01-12 11:22:40 +01:00
mmconf-fam10h_64.c x86: move various CPU initialization objects into .cpuinit.rodata 2009-03-12 13:13:07 +01:00
module_32.c x86: module_32.c fix style problems 2009-01-12 11:22:55 +01:00
module_64.c x86: module_64.c fix style problems 2009-01-12 11:23:01 +01:00
mpparse.c x86: mpparse.c introduce check_physptr helper function 2009-03-21 14:15:43 +05:30
msr.c x86: msr.c fix style problems 2009-01-12 11:22:50 +01:00
olpc.c x86, olpc: fix model detection without OFW 2009-02-14 23:05:25 +01:00
paravirt-spinlocks.c x86: remove byte locks 2009-01-20 17:14:28 +01:00
paravirt.c x86: with the last user gone, remove set_pte_present 2009-03-19 14:04:19 +01:00
paravirt_patch_32.c x86/pvops: add a paravirt_ident functions to allow special patching 2009-01-30 14:51:44 -08:00
paravirt_patch_64.c x86/pvops: add a paravirt_ident functions to allow special patching 2009-01-30 14:51:44 -08:00
pci-calgary_64.c x86, ia64: convert to use generic dma_map_ops struct 2009-01-06 14:06:57 +01:00
pci-dma.c Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 2009-04-01 09:47:12 -07:00
pci-gart_64.c Merge branch 'linus' into core/iommu 2009-03-05 12:47:28 +01:00
pci-nommu.c Merge branch 'iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-03-30 13:41:00 -07:00
pci-swiotlb.c x86: rename arch/x86/kernel/pci-swiotlb_64.c => pci-swiotlb.c 2009-01-23 12:06:44 +01:00
pcspeaker.c
pmtimer_64.c
probe_roms_32.c x86: move mach-default/*.h files to asm/ 2009-01-29 14:16:51 +01:00
process.c x86: reduce preemption off section in exit thread 2009-03-16 15:32:28 +01:00
process_32.c Simplify copy_thread() 2009-04-02 19:04:51 -07:00
process_64.c Simplify copy_thread() 2009-04-02 19:04:51 -07:00
ptrace.c signals: remove 'handler' parameter to tracehook functions 2009-04-02 19:04:58 -07:00
pvclock.c
quirks.c Merge branch 'linus' into x86/core 2009-03-28 22:27:45 +01:00
reboot.c Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2 2009-03-27 17:28:43 +01:00
reboot_fixups_32.c
relocate_kernel_32.S x86, kexec: fix kexec x86 coding style 2009-03-10 18:13:25 -07:00
relocate_kernel_64.S x86, kexec: x86_64: add kexec jump support for x86_64 2009-03-10 18:13:25 -07:00
rtc.c x86: rtc.c cleanup 2009-03-21 16:56:37 +05:30
scx200_32.c
setup.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask 2009-03-30 18:00:26 -07:00
setup_percpu.c percpu: generalize embedding first chunk setup helper 2009-03-10 16:27:48 +09:00
signal.c x86: signal: check signal stack overflow properly 2009-03-20 19:01:31 +01:00
smp.c x86, apic: remove genapic.h 2009-02-17 17:52:44 +01:00
smpboot.c x86: remove smp_apply_quirks()/smp_checks() 2009-03-08 16:22:56 +01:00
stacktrace.c x86: update copyrights 2009-01-31 04:21:18 +01:00
step.c
sys_i386_32.c
sys_x86_64.c
syscall_64.c
syscall_table_32.S x86: pass in pt_regs pointer for syscalls that need it 2009-02-11 12:40:45 +01:00
tce_64.c
test_nx.c
test_rodata.c
time_32.c x86: refactor x86_quirks support 2009-02-23 00:08:11 +01:00
time_64.c cpumask: remove references to struct irqaction's mask field. 2009-03-30 22:05:14 +10:30
tlb_uv.c x86, uv: fix cpumask iterator in uv_bau_init() 2009-03-18 09:47:54 +01:00
tls.c
tls.h
topology.c x86: topology.c cleanup 2009-03-21 16:55:24 +05:30
trampoline.c x86: change static allocation of trampoline area 2008-12-08 13:49:45 +01:00
trampoline_32.S x86: use _types.h headers in asm where available 2009-02-13 11:35:01 -08:00
trampoline_64.S x86: use _types.h headers in asm where available 2009-02-13 11:35:01 -08:00
traps.c x86-32: use non-lazy io bitmap context switching 2009-03-02 12:07:48 +01:00
tsc.c Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2 2009-03-27 17:28:43 +01:00
tsc_sync.c Merge branches 'x86/apic', 'x86/cleanups', 'x86/cpufeature', 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/detect-hyper', 'x86/doc', 'x86/dumpstack', 'x86/early-printk', 'x86/fpu', 'x86/idle', 'x86/io', 'x86/memory-corruption-check', 'x86/microcode', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/pat2', 'x86/pci-ioapic-boot-irq-quirks', 'x86/ptrace', 'x86/quirks', 'x86/reboot', 'x86/setup-memory', 'x86/signal', 'x86/sparse-fixes', 'x86/time', 'x86/uv' and 'x86/xen' into x86/core 2008-12-23 16:27:23 +01:00
uv_irq.c x86, apic: remove genapic.h 2009-02-17 17:52:44 +01:00
uv_sysfs.c
uv_time.c x86: UV, SGI RTC: fix uv_time.c for UP 2009-03-05 11:27:49 +01:00
verify_cpu_64.S
visws_quirks.c x86: convert obsolete irq_desc_t typedef to struct irq_desc 2009-03-11 09:49:01 +01:00
vm86_32.c x86: use regparm(3) for passed-in pt_regs pointer 2009-02-11 14:00:56 -08:00
vmi_32.c x86: with the last user gone, remove set_pte_present 2009-03-19 14:04:19 +01:00
vmiclock_32.c cpumask: remove references to struct irqaction's mask field. 2009-03-30 22:05:14 +10:30
vmlinux.lds.S
vmlinux_32.lds.S x86-32: move _end to a dummy section 2009-03-17 14:16:02 -07:00
vmlinux_64.lds.S x86/brk: put the brk reservations in their own section 2009-03-17 12:58:15 -07:00
vsmp_64.c Revert "x86: don't compile vsmp_64 for 32bit" 2009-03-25 21:34:28 +01:00
vsyscall_64.c Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-28 12:21:10 -08:00
x8664_ksyms_64.c x86: convert pda ops to wrappers around x86 percpu accessors 2009-01-16 14:20:22 +01:00
xsave.c x86: xsave.c: restore_user_xstate should be static 2008-12-30 13:31:41 -08:00