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2012-06-08Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar. * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Fix the relax_domain_level boot parameter sched: Validate assumptions in sched_init_numa() sched: Always initialize cpu-power sched: Fix domain iteration sched/rt: Fix lockdep annotation within find_lock_lowest_rq() sched/numa: Load balance between remote nodes sched/x86: Calculate booted cores after construction of sibling_mask
2012-06-08Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar. * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/nmi: Fix section mismatch warnings on 32-bit x86/uv: Fix UV2 BAU legacy mode x86/mm: Only add extra pages count for the first memory range during pre-allocation early page table space x86, efi stub: Add .reloc section back into image x86/ioapic: Fix NULL pointer dereference on CPU hotplug after disabling irqs x86/reboot: Fix a warning message triggered by stop_other_cpus() x86/intel/moorestown: Change intel_scu_devices_create() to __devinit x86/numa: Set numa_nodes_parsed at acpi_numa_memory_affinity_init() x86/gart: Fix kmemleak warning x86: mce: Add the dropped timer interval init back x86/mce: Fix the MCE poll timer logic
2012-06-08Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "A bit larger than what I'd wish for - half of it is due to hw driver updates to Intel Ivy-Bridge which info got recently released, cycles:pp should work there now too, amongst other things. (but we are generally making exceptions for hardware enablement of this type.) There are also callchain fixes in it - responding to mostly theoretical (but valid) concerns. The tooling side sports perf.data endianness/portability fixes which did not make it for the merge window - and various other fixes as well." * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits) perf/x86: Check user address explicitly in copy_from_user_nmi() perf/x86: Check if user fp is valid perf: Limit callchains to 127 perf/x86: Allow multiple stacks perf/x86: Update SNB PEBS constraints perf/x86: Enable/Add IvyBridge hardware support perf/x86: Implement cycles:p for SNB/IVB perf/x86: Fix Intel shared extra MSR allocation x86/decoder: Fix bsr/bsf/jmpe decoding with operand-size prefix perf: Remove duplicate invocation on perf_event_for_each perf uprobes: Remove unnecessary check before strlist__delete perf symbols: Check for valid dso before creating map perf evsel: Fix 32 bit values endianity swap for sample_id_all header perf session: Handle endianity swap on sample_id_all header data perf symbols: Handle different endians properly during symbol load perf evlist: Pass third argument to ioctl explicitly perf tools: Update ioctl documentation for PERF_IOC_FLAG_GROUP perf tools: Make --version show kernel version instead of pull req tag perf tools: Check if callchain is corrupted perf callchain: Make callchain cursors TLS ...
2012-06-08x86/nmi: Fix section mismatch warnings on 32-bitDon Zickus
It was reported that compiling for 32-bit caused a bunch of section mismatch warnings: VDSOSYM arch/x86/vdso/vdso32-syms.lds LD arch/x86/vdso/built-in.o LD arch/x86/built-in.o WARNING: arch/x86/built-in.o(.data+0x5af0): Section mismatch in reference from the variable test_nmi_ipi_callback_na.10451 to the function .init.text:test_nmi_ipi_callback() [...] WARNING: arch/x86/built-in.o(.data+0x5b04): Section mismatch in reference from the variable nmi_unk_cb_na.10399 to the function .init.text:nmi_unk_cb() The variable nmi_unk_cb_na.10399 references the function __init nmi_unk_cb() [...] Both of these are attributed to the internal representation of the nmiaction struct created during register_nmi_handler. The reason for this is that those structs are not defined in the init section whereas the rest of the code in nmi_selftest.c is. To resolve this, I created a new #define, register_nmi_handler_initonly, that tags the struct as __initdata to resolve the mismatch. This #define should only be used in rare situations where the register/unregister is called during init of the kernel. Big thanks to Jan Beulich for decoding this for me as I didn't have a clue what was going on. Reported-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl> Tested-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl> Cc: Jan Beulich <JBeulich@suse.com> Signed-off-by: Don Zickus <dzickus@redhat.com> Link: http://lkml.kernel.org/r/1338991542-23000-1-git-send-email-dzickus@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-08x86/uv: Fix UV2 BAU legacy modeCliff Wickman
The SGI Altix UV2 BAU (Broadcast Assist Unit) as used for tlb-shootdown (selective broadcast mode) always uses UV2 broadcast descriptor format. There is no need to clear the 'legacy' (UV1) mode, because the hardware always uses UV2 mode for selective broadcast. But the BIOS uses general broadcast and legacy mode, and the hardware pays attention to the legacy mode bit for general broadcast. So the kernel must not clear that mode bit. Signed-off-by: Cliff Wickman <cpw@sgi.com> Cc: <stable@kernel.org> Link: http://lkml.kernel.org/r/E1SccoO-0002Lh-Cb@eag09.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-08x86/mm: Only add extra pages count for the first memory range during ↵Yinghai Lu
pre-allocation early page table space Robin found this regression: | I just tried to boot an 8TB system. It fails very early in boot with: | Kernel panic - not syncing: Cannot find space for the kernel page tables git bisect commit 722bc6b16771ed80871e1fd81c86d3627dda2ac8. A git revert of that commit does boot past that point on the 8TB configuration. That commit will add up extra pages for all memory range even above 4g. Try to limit that extra page count adding to first entry only. Bisected-by: Robin Holt <holt@sgi.com> Tested-by: Robin Holt <holt@sgi.com> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: WANG Cong <xiyou.wangcong@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/CAE9FiQUj3wyzQxtq9yzBNc9u220p8JZ1FYHG7t%3DMOzJ%3D9BZMYA@mail.gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-07x86, efi stub: Add .reloc section back into imageJordan Justen
Some UEFI firmware will not load a .efi with a .reloc section with a size of 0. Therefore, we create a .efi image with 4 main areas and 3 sections. 1. PE/COFF file header 2. .setup section (covers all setup code following the first sector) 3. .reloc section (contains 1 dummy reloc entry, created in build.c) 4. .text section (covers the remaining kernel image) To make room for the new .setup section data, the header bugger_off_msg had to be shortened. Reported-by: Henrik Rydberg <rydberg@euromail.se> Signed-off-by: Jordan Justen <jordan.l.justen@intel.com> Link: http://lkml.kernel.org/r/1339085121-12760-1-git-send-email-jordan.l.justen@intel.com Tested-by: Lee G Rosenbaum <lee.g.rosenbaum@intel.com> Tested-by: Henrik Rydberg <rydberg@euromail.se> Cc: Matt Fleming <matt.fleming@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-06-06perf/x86: Check user address explicitly in copy_from_user_nmi()Arun Sharma
Signed-off-by: Arun Sharma <asharma@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1334961696-19580-5-git-send-email-asharma@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06perf/x86: Check if user fp is validArun Sharma
Signed-off-by: Arun Sharma <asharma@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1334961696-19580-4-git-send-email-asharma@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06perf/x86: Allow multiple stacksArun Sharma
Without this patch, applications with two different stack regions (eg: native stack vs JIT stack) get truncated callchains even when RBP chaining is present. GDB shows proper stack traces and the frame pointer chaining is intact. This patch disables the (fp < RSP) check, hoping that other checks in the code save the day for us. In our limited testing, this didn't seem to break anything. In the long term, we could potentially have userspace advise the kernel on the range of valid stack addresses, so we don't spend a lot of time unwinding from bogus addresses. Signed-off-by: Arun Sharma <asharma@fb.com> CC: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Stephane Eranian <eranian@google.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: linux-kernel@vger.kernel.org Cc: linux-perf-users@vger.kernel.org Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1334961696-19580-2-git-send-email-asharma@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06perf/x86: Update SNB PEBS constraintsPeter Zijlstra
Afaict there's no need to (incompletely) iterate the MEM_UOPS_RETIRED.* umask state. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1338884803.28282.153.camel@twins Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06perf/x86: Enable/Add IvyBridge hardware supportPeter Zijlstra
Implement rudimentary IVB perf support. The SDM states its identical to SNB with exception of the exact event tables, but a quick look suggests they're similar enough. Also mark SNB-EP as broken for now. Requested-and-tested-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1338884803.28282.153.camel@twins Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06perf/x86: Implement cycles:p for SNB/IVBPeter Zijlstra
Now that there's finally a chip with working PEBS (IvyBridge), we can enable the hardware and implement cycles:p for SNB/IVB. Cc: Stephane Eranian <eranian@google.com> Requested-and-tested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1338884803.28282.153.camel@twins Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06perf/x86: Fix Intel shared extra MSR allocationPeter Zijlstra
Zheng Yan reported that event group validation can wreck event state when Intel extra_reg allocation changes event state. Validation shouldn't change any persistent state. Cloning events in validate_{event,group}() isn't really pretty either, so add a few special cases to avoid modifying the event state. The code is restructured to minimize the special case impact. Reported-by: Zheng Yan <zheng.z.yan@linux.intel.com> Acked-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1338903031.28282.175.camel@twins Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06sched/x86: Calculate booted cores after construction of sibling_maskKamalesh Babulal
Commit 316ad248307fb ("sched/x86: Rewrite set_cpu_sibling_map()") broke the booted_cores accounting. The problem is that the booted_cores accounting needs all the sibling links set up. So restore the second loop and add a comment as to why its needed. On qemu booted with -smp sockets=1,cores=2,threads=2; Before: $ grep cores /proc/cpuinfo cpu cores : 2 cpu cores : 1 cpu cores : 4 cpu cores : 3 With the patch: $ grep cores /proc/cpuinfo cpu cores : 2 cpu cores : 2 cpu cores : 2 cpu cores : 2 Reported-by: Prarit Bhargava <prarit@redhat.com> Reported-by: Borislav Petkov <bp@amd64.org> Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20120531073738.GH7511@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06x86/ioapic: Fix NULL pointer dereference on CPU hotplug after disabling irqsTomoki Sekiyama
In current Linux, percpu variable `vector_irq' is not cleared on offlined cpus while disabling devices' irqs. If the cpu that has the disabled irqs in vector_irq is hotplugged, __setup_vector_irq() hits invalid irq vector and may crash. This bug can be reproduced as following; # echo 0 > /sys/devices/system/cpu/cpu7/online # modprobe -r some_driver_using_interrupts # vector_irq@cpu7 uncleared # echo 1 > /sys/devices/system/cpu/cpu7/online # kernel may crash This patch fixes this bug by clearing vector_irq in __clear_irq_vector() even if the cpu is offlined. Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: yrl.pp-manager.tt@hitachi.com Cc: ltc-kernel@ml.yrl.intra.hitachi.co.jp Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Alexander Gordeev <agordeev@redhat.com> Link: http://lkml.kernel.org/r/4FC340BE.7080101@hitachi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06x86/reboot: Fix a warning message triggered by stop_other_cpus()Feng Tang
When rebooting our 24 CPU Westmere servers with 3.4-rc6, we always see this warning msg: Restarting system. machine restart ------------[ cut here ]------------ WARNING: at arch/x86/kernel/smp.c:125 native_smp_send_reschedule+0x74/0xa7() Hardware name: X8DTN Modules linked in: igb [last unloaded: scsi_wait_scan] Pid: 1, comm: systemd-shutdow Not tainted 3.4.0-rc6+ #22 Call Trace: <IRQ> [<ffffffff8102a41f>] warn_slowpath_common+0x7e/0x96 [<ffffffff8102a44c>] warn_slowpath_null+0x15/0x17 [<ffffffff81018cf7>] native_smp_send_reschedule+0x74/0xa7 [<ffffffff810561c1>] trigger_load_balance+0x279/0x2a6 [<ffffffff81050112>] scheduler_tick+0xe0/0xe9 [<ffffffff81036768>] update_process_times+0x60/0x70 [<ffffffff81062f2f>] tick_sched_timer+0x68/0x92 [<ffffffff81046e33>] __run_hrtimer+0xb3/0x13c [<ffffffff81062ec7>] ? tick_nohz_handler+0xd0/0xd0 [<ffffffff810474f2>] hrtimer_interrupt+0xdb/0x198 [<ffffffff81019a35>] smp_apic_timer_interrupt+0x81/0x94 [<ffffffff81655187>] apic_timer_interrupt+0x67/0x70 <EOI> [<ffffffff8101a3c4>] ? default_send_IPI_mask_allbutself_phys+0xb4/0xc4 [<ffffffff8101c680>] physflat_send_IPI_allbutself+0x12/0x14 [<ffffffff81018db4>] native_nmi_stop_other_cpus+0x8a/0xd6 [<ffffffff810188ba>] native_machine_shutdown+0x50/0x67 [<ffffffff81018926>] machine_shutdown+0xa/0xc [<ffffffff8101897e>] native_machine_restart+0x20/0x32 [<ffffffff810189b0>] machine_restart+0xa/0xc [<ffffffff8103b196>] kernel_restart+0x47/0x4c [<ffffffff8103b2e6>] sys_reboot+0x13e/0x17c [<ffffffff8164e436>] ? _raw_spin_unlock_bh+0x10/0x12 [<ffffffff810fcac9>] ? bdi_queue_work+0xcf/0xd8 [<ffffffff810fe82f>] ? __bdi_start_writeback+0xae/0xb7 [<ffffffff810e0d64>] ? iterate_supers+0xa3/0xb7 [<ffffffff816547a2>] system_call_fastpath+0x16/0x1b ---[ end trace 320af5cb1cb60c5b ]--- The root cause seems to be the default_send_IPI_mask_allbutself_phys() takes quite some time (I measured it could be several ms) to complete sending NMIs to all the other 23 CPUs, and for HZ=250/1000 system, the time is long enough for a timer interrupt to happen, which will in turn trigger to kick load balance to a stopped CPU and cause this warning in native_smp_send_reschedule(). So disabling the local irq before stop_other_cpu() can fix this problem (tested 25 times reboot ok), and it is fine as there should be nobody caring the timer interrupt in such reboot stage. The latest 3.4 kernel slightly changes this behavior by sending REBOOT_VECTOR first and only send NMI_VECTOR if the REBOOT_VCTOR fails, and this patch is still needed to prevent the problem. Signed-off-by: Feng Tang <feng.tang@intel.com> Acked-by: Don Zickus <dzickus@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20120530231541.4c13433a@feng-i7 Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06x86/intel/moorestown: Change intel_scu_devices_create() to __devinitSebastian Andrzej Siewior
The allmodconfig hits: WARNING: vmlinux.o(.text+0x6553d): Section mismatch in reference from the function intel_scu_devices_create() to the function .devinit.text: spi_register_board_info() [...] This patch marks intel_scu_devices_create() as devinit because it only calls a devinit function, spi_register_board_info(). Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Cc: Alan Cox <alan@linux.intel.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Samuel Ortiz <sameo@linux.intel.com> Cc: Feng Tang <feng.tang@intel.com> Link: http://lkml.kernel.org/r/20120531212025.GA8519@breakpoint.cc Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06x86/numa: Set numa_nodes_parsed at acpi_numa_memory_affinity_init()Yasuaki Ishimatsu
When hot-adding a CPU, the system outputs following messages since node_to_cpumask_map[2] was not allocated memory. Booting Node 2 Processor 32 APIC 0xc0 node_to_cpumask_map[2] NULL Pid: 0, comm: swapper/32 Tainted: G A 3.3.5-acd #21 Call Trace: [<ffffffff81048845>] debug_cpumask_set_cpu+0x155/0x160 [<ffffffff8105e28a>] ? add_timer_on+0xaa/0x120 [<ffffffff8150665f>] numa_add_cpu+0x1e/0x22 [<ffffffff815020bb>] identify_cpu+0x1df/0x1e4 [<ffffffff815020d6>] identify_econdary_cpu+0x16/0x1d [<ffffffff81504614>] smp_store_cpu_info+0x3c/0x3e [<ffffffff81505263>] smp_callin+0x139/0x1be [<ffffffff815052fb>] start_secondary+0x13/0xeb The reason is that the bit of node 2 was not set at numa_nodes_parsed. numa_nodes_parsed is set by only acpi_numa_processor_affinity_init / acpi_numa_x2apic_affinity_init. Thus even if hot-added memory which is same PXM as hot-added CPU is written in ACPI SRAT Table, if the hot-added CPU is not written in ACPI SRAT table, numa_nodes_parsed is not set. But according to ACPI Spec Rev 5.0, it says about ACPI SRAT table as follows: This optional table provides information that allows OSPM to associate processors and memory ranges, including ranges of memory provided by hot-added memory devices, with system localities / proximity domains and clock domains. It means that ACPI SRAT table only provides information for CPUs present at boot time and for memory including hot-added memory. So hot-added memory is written in ACPI SRAT table, but hot-added CPU is not written in it. Thus numa_nodes_parsed should be set by not only acpi_numa_processor_affinity_init / acpi_numa_x2apic_affinity_init but also acpi_numa_memory_affinity_init for the case. Additionally, if system has cpuless memory node, acpi_numa_processor_affinity_init / acpi_numa_x2apic_affinity_init cannot set numa_nodes_parseds since these functions cannot find cpu description for the node. In this case, numa_nodes_parsed needs to be set by acpi_numa_memory_affinity_init. Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: liuj97@gmail.com Cc: kosaki.motohiro@gmail.com Link: http://lkml.kernel.org/r/4FCC2098.4030007@jp.fujitsu.com [ merged it ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06x86/gart: Fix kmemleak warningXiaotian Feng
aperture_64.c now is using memblock, the previous kmemleak_ignore() for alloc_bootmem() should be removed then. Otherwise, with kmemleak enabled, kernel will throw warnings like: [ 0.000000] kmemleak: Trying to color unknown object at 0xffff8800c4000000 as Black [ 0.000000] Pid: 0, comm: swapper/0 Not tainted 3.5.0-rc1-next-20120605+ #130 [ 0.000000] Call Trace: [ 0.000000] [<ffffffff811b27e6>] paint_ptr+0x66/0xc0 [ 0.000000] [<ffffffff816b90fb>] kmemleak_ignore+0x2b/0x60 [ 0.000000] [<ffffffff81ef7bc0>] kmemleak_init+0x217/0x2c1 [ 0.000000] [<ffffffff81ed2b97>] start_kernel+0x32d/0x3eb [ 0.000000] [<ffffffff81ed25e4>] ? repair_env_string+0x5a/0x5a [ 0.000000] [<ffffffff81ed2356>] x86_64_start_reservations+0x131/0x135 [ 0.000000] [<ffffffff81ed2120>] ? early_idt_handlers+0x120/0x120 [ 0.000000] [<ffffffff81ed245c>] x86_64_start_kernel+0x102/0x111 [ 0.000000] kmemleak: Early log backtrace: [ 0.000000] [<ffffffff816b911b>] kmemleak_ignore+0x4b/0x60 [ 0.000000] [<ffffffff81ee6a38>] gart_iommu_hole_init+0x3e7/0x547 [ 0.000000] [<ffffffff81edb20b>] pci_iommu_alloc+0x44/0x6f [ 0.000000] [<ffffffff81ee81ad>] mem_init+0x19/0xec [ 0.000000] [<ffffffff81ed2a54>] start_kernel+0x1ea/0x3eb [ 0.000000] [<ffffffff81ed2356>] x86_64_start_reservations+0x131/0x135 [ 0.000000] [<ffffffff81ed245c>] x86_64_start_kernel+0x102/0x111 [ 0.000000] [<ffffffffffffffff>] 0xffffffffffffffff Signed-off-by: Xiaotian Feng <dannyfeng@tencent.com> Cc: Xiaotian Feng <xtfeng@gmail.com> Cc: Tejun Heo <tj@kernel.org> Link: http://lkml.kernel.org/r/1338922831-2847-1-git-send-email-xtfeng@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06x86: mce: Add the dropped timer interval init backThomas Gleixner
commit 82f7af09 ("x86/mce: Cleanup timer mess) dropped the initialization of the per cpu timer interval. Duh :( Restore the previous behaviour. Reported-by: Chen Gong <gong.chen@linux.intel.com> Cc: bp@amd64.org Cc: tony.luck@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-06-06x86/decoder: Fix bsr/bsf/jmpe decoding with operand-size prefixMasami Hiramatsu
Fix the x86 instruction decoder to decode bsr/bsf/jmpe with operand-size prefix (66h). This fixes the test case failure reported by Linus, attached below. bsf/bsr/jmpe have a special encoding. Opcode map in Intel Software Developers Manual vol2 says they have TZCNT/LZCNT variants if it has F3h prefix. However, there is no information if it has other 66h or F2h prefixes. Current instruction decoder supposes that those are bad instructions, but it actually accepts at least operand-size prefixes. H. Peter Anvin further explains: " TZCNT/LZCNT are F3 + BSF/BSR exactly because the F2 and F3 prefixes have historically been no-ops with most instructions. This allows software to unconditionally use the prefixed versions and get TZCNT/LZCNT on the processors that have them if they don't care about the difference. " This fixes errors reported by test_get_len: Warning: arch/x86/tools/test_get_len found difference at <em_bsf>:ffffffff81036d87 Warning: ffffffff81036de5: 66 0f bc c2 bsf %dx,%ax Warning: objdump says 4 bytes, but insn_get_length() says 3 Warning: arch/x86/tools/test_get_len found difference at <em_bsr>:ffffffff81036ea6 Warning: ffffffff81036f04: 66 0f bd c2 bsr %dx,%ax Warning: objdump says 4 bytes, but insn_get_length() says 3 Warning: decoded and checked 13298882 instructions with 2 warnings Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <yrl.pp-manager.tt@hitachi.com> Link: http://lkml.kernel.org/r/20120604150911.22338.43296.stgit@localhost.localdomain Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06x86/mce: Fix the MCE poll timer logicChen Gong
In commit 82f7af09 ("x86/mce: Cleanup timer mess), Thomas just forgot the "/ 2" there while cleaning up. Signed-off-by: Chen Gong <gong.chen@linux.intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: bp@amd64.org Cc: tony.luck@intel.com Link: http://lkml.kernel.org/r/1338863702-9245-1-git-send-email-gong.chen@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-05Merge tag 'please-pull-mce' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras Pull MCE regression fix from Tony Luck: "Typo/thinko in a cleanup caused a semantic change. Fix it." * tag 'please-pull-mce' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras: x86/mce: Fix the MCE poll timer logic
2012-06-05x86/mce: Fix the MCE poll timer logicChen Gong
In commit 82f7af09 (x86/mce: Cleanup timer mess), Thomas just forgot the "/ 2" there while cleaning up. Signed-off-by: Chen Gong <gong.chen@linux.intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Tony Luck <tony.luck@intel.com>
2012-06-05Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar. * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Remove NULL assignment of dattr_cur sched: Remove the last NULL entry from sched_feat_names sched: Make sched_feat_names const sched/rt: Fix SCHED_RR across cgroups sched: Move nr_cpus_allowed out of 'struct sched_rt_entity' sched: Make sure to not re-read variables after validation sched: Fix SD_OVERLAP sched: Don't try allocating memory from offline nodes sched/nohz: Fix rq->cpu_load calculations some more sched/x86: Use cpu_llc_shared_mask(cpu) for coregroup_mask
2012-06-02Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull straggler x86 fixes from Peter Anvin: "Three groups of patches: - EFI boot stub documentation and the ability to print error messages; - Removal for PTRACE_ARCH_PRCTL for x32 (obsolete interface which should never have been ported, and the port is broken and potentially dangerous.) - ftrace stack corruption fixes. I'm not super-happy about the technical implementation, but it is probably the least invasive in the short term. In the future I would like a single method for nesting the debug stack, however." * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, x32, ptrace: Remove PTRACE_ARCH_PRCTL for x32 x86, efi: Add EFI boot stub documentation x86, efi; Add EFI boot stub console support x86, efi: Only close open files in error path ftrace/x86: Do not change stacks in DEBUG when calling lockdep x86: Allow nesting of the debug stack IDT setting x86: Reset the debug_stack update counter ftrace: Use breakpoint method to update ftrace caller ftrace: Synchronize variable setting with breakpoints
2012-06-01Merge remote-tracking branch 'rostedt/tip/perf/urgent-2' into ↵H. Peter Anvin
x86-urgent-for-linus
2012-06-01x86, x32, ptrace: Remove PTRACE_ARCH_PRCTL for x32H.J. Lu
When I added x32 ptrace to 3.4 kernel, I also include PTRACE_ARCH_PRCTL support for x32 GDB For ARCH_GET_FS/GS, it takes a pointer to int64. But at user level, ARCH_GET_FS/GS takes a pointer to int32. So I have to add x32 ptrace to glibc to handle it with a temporary int64 passed to kernel and copy it back to GDB as int32. Roland suggested that PTRACE_ARCH_PRCTL is obsolete and x32 GDB should use fs_base and gs_base fields of user_regs_struct instead. Accordingly, remove PTRACE_ARCH_PRCTL completely from the x32 code to avoid possible memory overrun when pointer to int32 is passed to kernel. Link: http://lkml.kernel.org/r/CAMe9rOpDzHfS7NH7m1vmD9QRw8SSj4Sc%2BaNOgcWm_WJME2eRsQ@mail.gmail.com Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: <stable@vger.kernel.org> v3.4
2012-06-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull third pile of signal handling patches from Al Viro: "This time it's mostly helpers and conversions to them; there's a lot of stuff remaining in the tree, but that'll either go in -rc2 (isolated bug fixes, ideally via arch maintainers' trees) or will sit there until the next cycle." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: x86: get rid of calling do_notify_resume() when returning to kernel mode blackfin: check __get_user() return value whack-a-mole with TIF_FREEZE FRV: Optimise the system call exit path in entry.S [ver #2] FRV: Shrink TIF_WORK_MASK [ver #2] FRV: Prevent syscall exit tracing and notify_resume at end of kernel exceptions new helper: signal_delivered() powerpc: get rid of restore_sigmask() most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set set_restore_sigmask() is never called without SIGPENDING (and never should be) TIF_RESTORE_SIGMASK can be set only when TIF_SIGPENDING is set don't call try_to_freeze() from do_signal() pull clearing RESTORE_SIGMASK into block_sigmask() sh64: failure to build sigframe != signal without handler openrisc: tracehook_signal_handler() is supposed to be called on success new helper: sigmask_to_save() new helper: restore_saved_sigmask() new helpers: {clear,test,test_and_clear}_restore_sigmask() HAVE_RESTORE_SIGMASK is defined on all architectures now
2012-06-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs changes from Al Viro. "A lot of misc stuff. The obvious groups: * Miklos' atomic_open series; kills the damn abuse of ->d_revalidate() by NFS, which was the major stumbling block for all work in that area. * ripping security_file_mmap() and dealing with deadlocks in the area; sanitizing the neighborhood of vm_mmap()/vm_munmap() in general. * ->encode_fh() switched to saner API; insane fake dentry in mm/cleancache.c gone. * assorted annotations in fs (endianness, __user) * parts of Artem's ->s_dirty work (jff2 and reiserfs parts) * ->update_time() work from Josef. * other bits and pieces all over the place. Normally it would've been in two or three pull requests, but signal.git stuff had eaten a lot of time during this cycle ;-/" Fix up trivial conflicts in Documentation/filesystems/vfs.txt (the 'truncate_range' inode method was removed by the VM changes, the VFS update adds an 'update_time()' method), and in fs/btrfs/ulist.[ch] (due to sparse fix added twice, with other changes nearby). * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (95 commits) nfs: don't open in ->d_revalidate vfs: retry last component if opening stale dentry vfs: nameidata_to_filp(): don't throw away file on error vfs: nameidata_to_filp(): inline __dentry_open() vfs: do_dentry_open(): don't put filp vfs: split __dentry_open() vfs: do_last() common post lookup vfs: do_last(): add audit_inode before open vfs: do_last(): only return EISDIR for O_CREAT vfs: do_last(): check LOOKUP_DIRECTORY vfs: do_last(): make ENOENT exit RCU safe vfs: make follow_link check RCU safe vfs: do_last(): use inode variable vfs: do_last(): inline walk_component() vfs: do_last(): make exit RCU safe vfs: split do_lookup() Btrfs: move over to use ->update_time fs: introduce inode operation ->update_time reiserfs: get rid of resierfs_sync_super reiserfs: mark the superblock as dirty a bit later ...
2012-06-01x86: get rid of calling do_notify_resume() when returning to kernel modeAl Viro
If we end up calling do_notify_resume() with !user_mode(refs), it does nothing (do_signal() explicitly bails out and we can't get there with TIF_NOTIFY_RESUME in such situations). Then we jump to resume_userspace_sig, which rechecks the same thing and bails out to resume_kernel, thus breaking the loop. It's easier and cheaper to check *before* calling do_notify_resume() and bail out to resume_kernel immediately. And kill the check in do_signal()... Note that on amd64 we can't get there with !user_mode() at all - asm glue takes care of that. Acked-and-reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01new helper: signal_delivered()Al Viro
Does block_sigmask() + tracehook_signal_handler(); called when sigframe has been successfully built. All architectures converted to it; block_sigmask() itself is gone now (merged into this one). I'm still not too happy with the signature, but that's a separate story (IMO we need a structure that would contain signal number + siginfo + k_sigaction, so that get_signal_to_deliver() would fill one, signal_delivered(), handle_signal() and probably setup...frame() - take one). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from setAl Viro
Only 3 out of 63 do not. Renamed the current variant to __set_current_blocked(), added set_current_blocked() that will exclude unblockable signals, switched open-coded instances to it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01set_restore_sigmask() is never called without SIGPENDING (and never should be)Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01pull clearing RESTORE_SIGMASK into block_sigmask()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01new helper: sigmask_to_save()Al Viro
replace boilerplate "should we use ->saved_sigmask or ->blocked?" with calls of obvious inlined helper... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01new helper: restore_saved_sigmask()Al Viro
first fruits of ..._restore_sigmask() helpers: now we can take boilerplate "signal didn't have a handler, clear RESTORE_SIGMASK and restore the blocked mask from ->saved_mask" into a common helper. Open-coded instances switched... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01new helpers: {clear,test,test_and_clear}_restore_sigmask()Al Viro
helpers parallel to set_restore_sigmask(), used in the next commits Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01x86, efi: Add EFI boot stub documentationMatt Fleming
Since we can't expect every user to read the EFI boot stub code it seems prudent to have a couple of paragraphs explaining what it is and how it works. The "initrd=" option in particular is tricky because it only understands absolute EFI-style paths (backslashes as directory separators), and until now this hasn't been documented anywhere. This has tripped up a couple of users. Cc: Matthew Garrett <mjg@redhat.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Link: http://lkml.kernel.org/r/1331907517-3985-4-git-send-email-matt@console-pimps.org Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-06-01x86, efi; Add EFI boot stub console supportMatt Fleming
We need a way of printing useful messages to the user, for example when we fail to open an initrd file, instead of just hanging the machine without giving the user any indication of what went wrong. So sprinkle some error messages throughout the EFI boot stub code to make it easier for users to diagnose/report problems. Reported-by: Keshav P R <the.ridikulus.rat@gmail.com> Cc: Matthew Garrett <mjg@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Link: http://lkml.kernel.org/r/1331907517-3985-3-git-send-email-matt@console-pimps.org Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-06-01x86, efi: Only close open files in error pathMatt Fleming
The loop at the 'close_handles' label in handle_ramdisks() should be using 'i', which represents the number of initrd files that were successfully opened, not 'nr_initrds' which is the number of initrd= arguments passed on the command line. Currently, if we execute the loop to close all file handles and we failed to open any initrds we'll try to call the close function on a garbage pointer, causing the machine to hang. Cc: Matthew Garrett <mjg@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Link: http://lkml.kernel.org/r/1331907517-3985-2-git-send-email-matt@console-pimps.org Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-06-01ftrace/x86: Do not change stacks in DEBUG when calling lockdepSteven Rostedt
When both DYNAMIC_FTRACE and LOCKDEP are set, the TRACE_IRQS_ON/OFF will call into the lockdep code. The lockdep code can call lots of functions that may be traced by ftrace. When ftrace is updating its code and hits a breakpoint, the breakpoint handler will call into lockdep. If lockdep happens to call a function that also has a breakpoint attached, it will jump back into the breakpoint handler resetting the stack to the debug stack and corrupt the contents currently on that stack. The 'do_sym' call that calls do_int3() is protected by modifying the IST table to point to a different location if another breakpoint is hit. But the TRACE_IRQS_OFF/ON are outside that protection, and if a breakpoint is hit from those, the stack will get corrupted, and the kernel will crash: [ 1013.243754] BUG: unable to handle kernel NULL pointer dereference at 0000000000000002 [ 1013.272665] IP: [<ffff880145cc0000>] 0xffff880145cbffff [ 1013.285186] PGD 1401b2067 PUD 14324c067 PMD 0 [ 1013.298832] Oops: 0010 [#1] PREEMPT SMP [ 1013.310600] CPU 2 [ 1013.317904] Modules linked in: ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables crc32c_intel ghash_clmulni_intel microcode usb_debug serio_raw pcspkr iTCO_wdt i2c_i801 iTCO_vendor_support e1000e nfsd nfs_acl auth_rpcgss lockd sunrpc i915 video i2c_algo_bit drm_kms_helper drm i2c_core [last unloaded: scsi_wait_scan] [ 1013.401848] [ 1013.407399] Pid: 112, comm: kworker/2:1 Not tainted 3.4.0+ #30 [ 1013.437943] RIP: 8eb8:[<ffff88014630a000>] [<ffff88014630a000>] 0xffff880146309fff [ 1013.459871] RSP: ffffffff8165e919:ffff88014780f408 EFLAGS: 00010046 [ 1013.477909] RAX: 0000000000000001 RBX: ffffffff81104020 RCX: 0000000000000000 [ 1013.499458] RDX: ffff880148008ea8 RSI: ffffffff8131ef40 RDI: ffffffff82203b20 [ 1013.521612] RBP: ffffffff81005751 R08: 0000000000000000 R09: 0000000000000000 [ 1013.543121] R10: ffffffff82cdc318 R11: 0000000000000000 R12: ffff880145cc0000 [ 1013.564614] R13: ffff880148008eb8 R14: 0000000000000002 R15: ffff88014780cb40 [ 1013.586108] FS: 0000000000000000(0000) GS:ffff880148000000(0000) knlGS:0000000000000000 [ 1013.609458] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 1013.627420] CR2: 0000000000000002 CR3: 0000000141f10000 CR4: 00000000001407e0 [ 1013.649051] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1013.670724] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 1013.692376] Process kworker/2:1 (pid: 112, threadinfo ffff88013fe0e000, task ffff88014020a6a0) [ 1013.717028] Stack: [ 1013.724131] ffff88014780f570 ffff880145cc0000 0000400000004000 0000000000000000 [ 1013.745918] cccccccccccccccc ffff88014780cca8 ffffffff811072bb ffffffff81651627 [ 1013.767870] ffffffff8118f8a7 ffffffff811072bb ffffffff81f2b6c5 ffffffff81f11bdb [ 1013.790021] Call Trace: [ 1013.800701] Code: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a <e7> d7 64 81 ff ff ff ff 01 00 00 00 00 00 00 00 65 d9 64 81 ff [ 1013.861443] RIP [<ffff88014630a000>] 0xffff880146309fff [ 1013.884466] RSP <ffff88014780f408> [ 1013.901507] CR2: 0000000000000002 The solution was to reuse the NMI functions that change the IDT table to make the debug stack keep its current stack (in kernel mode) when hitting a breakpoint: call debug_stack_set_zero TRACE_IRQS_ON call debug_stack_reset If the TRACE_IRQS_ON happens to hit a breakpoint then it will keep the current stack and not crash the box. Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-01x86: Allow nesting of the debug stack IDT settingSteven Rostedt
When the NMI handler runs, it checks if it preempted a debug handler and if that handler is using the debug stack. If it is, it changes the IDT table not to update the stack, otherwise it will reset the debug stack and corrupt the debug handler it preempted. Now that ftrace uses breakpoints to change functions from nops to callers, many more places may hit a breakpoint. Unfortunately this includes some of the calls that lockdep performs. Which causes issues with the debug stack. It too needs to change the debug stack before tracing (if called from the debug handler). Allow the debug_stack_set_zero() and debug_stack_reset() to be nested so that the debug handlers can take advantage of them too. [ Used this_cpu_*() over __get_cpu_var() as suggested by H. Peter Anvin ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-01x86: Reset the debug_stack update counterSteven Rostedt
When an NMI goes off and it sees that it preempted the debug stack, to keep the debug stack safe, it changes the IDT to point to one that does not modify the stack on breakpoint (to allow breakpoints in NMIs). But the variable that gets set to know to undo it on exit never gets cleared on exit. Thus every NMI will reset it on exit the first time it is done even if it does not need to be reset. [ Added H. Peter Anvin's suggestion to use this_cpu_read/write ] Cc: <stable@vger.kernel.org> # v3.3 Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-01ftrace: Use breakpoint method to update ftrace callerSteven Rostedt
On boot up and module load, it is fine to modify the code directly, without the use of breakpoints. This is because boot up modification is done before SMP is initialized, thus the modification is serial, and module load is done before the module executes. But after that we must use a SMP safe method to modify running code. Otherwise, if we are running the function tracer and update its function (by starting off the stack tracer, or perf tracing) the change of the function called by the ftrace trampoline is done directly. If this is being executed on another CPU, that CPU may take a GPF and crash the kernel. The breakpoint method is used to change the nops at all the functions, but the change of the ftrace callback handler itself was still using a direct modification. If tracing was enabled and the function callback was changed then another CPU could fault if it was currently calling the original callback. This modification must use the breakpoint method too. Note, the direct method is still used for boot up and module load. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-01ftrace: Synchronize variable setting with breakpointsSteven Rostedt
When the function tracer starts modifying the code via breakpoints it sets a variable (modifying_ftrace_code) to inform the breakpoint handler to call the ftrace int3 code. But there's no synchronization between setting this code and the handler, thus it is possible for the handler to be called on another CPU before it sees the variable. This will cause a kernel crash as the int3 handler will not know what to do with it. I originally added smp_mb()'s to force the visibility of the variable but H. Peter Anvin suggested that I just make it atomic. [ Added comments as suggested by Peter Zijlstra ] Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-06-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull second pile of signal handling patches from Al Viro: "This one is just task_work_add() series + remaining prereqs for it. There probably will be another pull request from that tree this cycle - at least for helpers, to get them out of the way for per-arch fixes remaining in the tree." Fix trivial conflict in kernel/irq/manage.c: the merge of Andrew's pile had brought in commit 97fd75b7b8e0 ("kernel/irq/manage.c: use the pr_foo() infrastructure to prefix printks") which changed one of the pr_err() calls that this merge moves around. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: keys: kill task_struct->replacement_session_keyring keys: kill the dummy key_replace_session_keyring() keys: change keyctl_session_to_parent() to use task_work_add() genirq: reimplement exit_irq_thread() hook via task_work_add() task_work_add: generic process-context callbacks avr32: missed _TIF_NOTIFY_RESUME on one of do_notify_resume callers parisc: need to check NOTIFY_RESUME when exiting from syscall move key_repace_session_keyring() into tracehook_notify_resume() TIF_NOTIFY_RESUME is defined on all targets now
2012-06-01Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds
Merge misc patches from Andrew Morton: - the "misc" tree - stuff from all over the map - checkpatch updates - fatfs - kmod changes - procfs - cpumask - UML - kexec - mqueue - rapidio - pidns - some checkpoint-restore feature work. Reluctantly. Most of it delayed a release. I'm still rather worried that we don't have a clear roadmap to completion for this work. * emailed from Andrew Morton <akpm@linux-foundation.org>: (78 patches) kconfig: update compression algorithm info c/r: prctl: add ability to set new mm_struct::exe_file c/r: prctl: extend PR_SET_MM to set up more mm_struct entries c/r: procfs: add arg_start/end, env_start/end and exit_code members to /proc/$pid/stat syscalls, x86: add __NR_kcmp syscall fs, proc: introduce /proc/<pid>/task/<tid>/children entry sysctl: make kernel.ns_last_pid control dependent on CHECKPOINT_RESTORE aio/vfs: cleanup of rw_copy_check_uvector() and compat_rw_copy_check_uvector() eventfd: change int to __u64 in eventfd_signal() fs/nls: add Apple NLS pidns: make killed children autoreap pidns: use task_active_pid_ns in do_notify_parent rapidio/tsi721: add DMA engine support rapidio: add DMA engine support for RIO data transfers ipc/mqueue: add rbtree node caching support tools/selftests: add mq_perf_tests ipc/mqueue: strengthen checks on mqueue creation ipc/mqueue: correct mq_attr_ok test ipc/mqueue: improve performance of send/recv selftests: add mq_open_tests ...
2012-06-01syscalls, x86: add __NR_kcmp syscallCyrill Gorcunov
While doing the checkpoint-restore in the user space one need to determine whether various kernel objects (like mm_struct-s of file_struct-s) are shared between tasks and restore this state. The 2nd step can be solved by using appropriate CLONE_ flags and the unshare syscall, while there's currently no ways for solving the 1st one. One of the ways for checking whether two tasks share e.g. mm_struct is to provide some mm_struct ID of a task to its proc file, but showing such info considered to be not that good for security reasons. Thus after some debates we end up in conclusion that using that named 'comparison' syscall might be the best candidate. So here is it -- __NR_kcmp. It takes up to 5 arguments - the pids of the two tasks (which characteristics should be compared), the comparison type and (in case of comparison of files) two file descriptors. Lookups for pids are done in the caller's PID namespace only. At moment only x86 is supported and tested. [akpm@linux-foundation.org: fix up selftests, warnings] [akpm@linux-foundation.org: include errno.h] [akpm@linux-foundation.org: tweak comment text] Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Andrey Vagin <avagin@openvz.org> Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Glauber Costa <glommer@parallels.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Tejun Heo <tj@kernel.org> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Valdis.Kletnieks@vt.edu Cc: Michal Marek <mmarek@suse.cz> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>