27 Oct, 2009
1 commit
-
We dont need to depend on PPC64 explicitly as all powerpc platforms
(32-bit and 64-bit) define PPC now.Signed-off-by: Kumar Gala
Signed-off-by: Benjamin Herrenschmidt
09 Oct, 2009
1 commit
-
…/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
futex: fix requeue_pi key imbalance
futex: Fix typo in FUTEX_WAIT/WAKE_BITSET_PRIVATE definitions
rcu: Place root rcu_node structure in separate lockdep class
rcu: Make hot-unplugged CPU relinquish its own RCU callbacks
rcu: Move rcu_barrier() to rcutree
futex: Move exit_pi_state() call to release_mm()
futex: Nullify robust lists after cleanup
futex: Fix locking imbalance
panic: Fix panic message visibility by calling bust_spinlocks(0) before dying
rcu: Replace the rcu_barrier enum with pointer to call_rcu*() function
rcu: Clean up code based on review feedback from Josh Triplett, part 4
rcu: Clean up code based on review feedback from Josh Triplett, part 3
rcu: Fix rcu_lock_map build failure on CONFIG_PROVE_LOCKING=y
rcu: Clean up code to address Ingo's checkpatch feedback
rcu: Clean up code based on review feedback from Josh Triplett, part 2
rcu: Clean up code based on review feedback from Josh Triplett
06 Oct, 2009
1 commit
-
Some architectures such as Sparc, ARM and MIPS (basically
everything with flush_dcache_page()) need to deal with dcache
aliases by carefully placing pages in both kernel and user maps.These architectures typically have to use vmalloc_user() for this.
However, on other architectures, vmalloc() is not needed and has
the downsides of being more restricted and slower than regular
allocations.Signed-off-by: Peter Zijlstra
Acked-by: David Miller
Cc: Andrew Morton
Cc: Jens Axboe
Cc: Paul Mackerras
LKML-Reference:
Signed-off-by: Ingo Molnar
24 Sep, 2009
6 commits
-
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: (39 commits)
cpumask: Move deprecated functions to end of header.
cpumask: remove unused deprecated functions, avoid accusations of insanity
cpumask: use new-style cpumask ops in mm/quicklist.
cpumask: use mm_cpumask() wrapper: x86
cpumask: use mm_cpumask() wrapper: um
cpumask: use mm_cpumask() wrapper: mips
cpumask: use mm_cpumask() wrapper: mn10300
cpumask: use mm_cpumask() wrapper: m32r
cpumask: use mm_cpumask() wrapper: arm
cpumask: Use accessors for cpu_*_mask: um
cpumask: Use accessors for cpu_*_mask: powerpc
cpumask: Use accessors for cpu_*_mask: mips
cpumask: Use accessors for cpu_*_mask: m32r
cpumask: remove arch_send_call_function_ipi
cpumask: arch_send_call_function_ipi_mask: s390
cpumask: arch_send_call_function_ipi_mask: powerpc
cpumask: arch_send_call_function_ipi_mask: mips
cpumask: arch_send_call_function_ipi_mask: m32r
cpumask: arch_send_call_function_ipi_mask: alpha
cpumask: remove obsolete topology_core_siblings and topology_thread_siblings: ia64
... -
* remove asm/atomic.h inclusion from linux/utsname.h --
not needed after kref conversion
* remove linux/utsname.h inclusion from files which do not need itNOTE: it looks like fs/binfmt_elf.c do not need utsname.h, however
due to some personality stuff it _is_ needed -- cowardly leave ELF-related
headers and files alone.Signed-off-by: Alexey Dobriyan
Signed-off-by: Linus Torvalds -
It's only defined for NR_CPUS > BITS_PER_LONG; cpu_all_mask is always
defined (and const).Signed-off-by: Rusty Russell
-
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next: (30 commits)
Use macros for .data.page_aligned section.
Use macros for .bss.page_aligned section.
Use new __init_task_data macro in arch init_task.c files.
kbuild: Don't define ALIGN and ENTRY when preprocessing linker scripts.
arm, cris, mips, sparc, powerpc, um, xtensa: fix build with bash 4.0
kbuild: add static to prototypes
kbuild: fail build if recordmcount.pl fails
kbuild: set -fconserve-stack option for gcc 4.5
kbuild: echo the record_mcount command
gconfig: disable "typeahead find" search in treeviews
kbuild: fix cc1 options check to ensure we do not use -fPIC when compiling
checkincludes.pl: add option to remove duplicates in place
markup_oops: use modinfo to avoid confusion with underscored module names
checkincludes.pl: provide usage helper
checkincludes.pl: close file as soon as we're done with it
ctags: usability fix
kernel hacking: move STRIP_ASM_SYMS from General
gitignore usr/initramfs_data.cpio.bz2 and usr/initramfs_data.cpio.lzma
kbuild: Check if linker supports the -X option
kbuild: introduce ld-option
...Fix trivial conflict in scripts/basic/fixdep.c
-
These issues identified during an old-fashioned face-to-face code
review extending over many hours.o Add comments for tricky parts of code, and correct comments
that have passed their sell-by date.o Get rid of the vestiges of rcu_init_sched(), which is no
longer needed now that PREEMPT_RCU is gone.o Move the #include of rcutree_plugin.h to the end of
rcutree.c, which means that, rather than having a random
collection of forward declarations, the new set of forward
declarations document the set of plugins. The new home for
this #include also allows __rcu_init_preempt() to move into
rcutree_plugin.h.o Fix rcu_preempt_check_callbacks() to be static.
Suggested-by: Josh Triplett
Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar
Peter Zijlstra -
* 'sfi-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-sfi-2.6:
SFI: remove unneeded includes
sfi: Remove unused code
SFI: Hook PCI MMCONFIG
x86: add arch-specific SFI support
SFI: add capability to parse ACPI tables
SFI: add platform-independent core support
SFI: create linux/sfi.h
SFI: Simple Firmware Interface - MAINTAINERS, Kconfig
22 Sep, 2009
3 commits
-
Sizing of memory allocations shouldn't depend on the number of physical
pages found in a system, as that generally includes (perhaps a huge amount
of) non-RAM pages. The amount of what actually is usable as storage
should instead be used as a basis here.Some of the calculations (i.e. those not intending to use high memory)
should likely even use (totalram_pages - totalhigh_pages).Signed-off-by: Jan Beulich
Acked-by: Rusty Russell
Acked-by: Ingo Molnar
Cc: Dave Airlie
Cc: Kyle McMartin
Cc: Jeremy Fitzhardinge
Cc: Pekka Enberg
Cc: Hugh Dickins
Cc: "David S. Miller"
Cc: Patrick McHardy
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
…ux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-rename-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf: Tidy up after the big rename
perf: Do the big rename: Performance Counters -> Performance Events
perf_counter: Rename 'event' to event_id/hw_event
perf_counter: Rename list_entry -> group_entry, counter_list -> group_listManually resolved some fairly trivial conflicts with the tracing tree in
include/trace/ftrace.h and kernel/trace/trace_syscalls.c. -
…/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
rcu: Fix whitespace inconsistencies
rcu: Fix thinko, actually initialize full tree
rcu: Apply results of code inspection of kernel/rcutree_plugin.h
rcu: Add WARN_ON_ONCE() consistency checks covering state transitions
rcu: Fix synchronize_rcu() for TREE_PREEMPT_RCU
rcu: Simplify rcu_read_unlock_special() quiescent-state accounting
rcu: Add debug checks to TREE_PREEMPT_RCU for premature grace periods
rcu: Kconfig help needs to say that TREE_PREEMPT_RCU scales down
rcutorture: Occasionally delay readers enough to make RCU force_quiescent_state
rcu: Initialize multi-level RCU grace periods holding locks
rcu: Need to update rnp->gpnum if preemptable RCU is to be reliable
21 Sep, 2009
2 commits
-
- provide compatibility Kconfig entry for existing PERF_COUNTERS .config's
- provide courtesy copy of old perf_counter.h, for user-space projects
- small indentation fixups
- fix up MAINTAINERS
- fix small x86 printout fallout
- fix up small PowerPC comment fallout (use 'counter' as in register)
Reviewed-by: Arjan van de Ven
Acked-by: Peter Zijlstra
Cc: Mike Galbraith
Cc: Paul Mackerras
Cc: Benjamin Herrenschmidt
Cc: Frederic Weisbecker
LKML-Reference:
Signed-off-by: Ingo Molnar -
Bye-bye Performance Counters, welcome Performance Events!
In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)This patch has been generated via the following script:
FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
sed -i \
-e 's/PERF_EVENT_/PERF_RECORD_/g' \
-e 's/PERF_COUNTER/PERF_EVENT/g' \
-e 's/perf_counter/perf_event/g' \
-e 's/nb_counters/nb_events/g' \
-e 's/swcounter/swevent/g' \
-e 's/tpcounter_event/tp_event/g' \
$FILESfor N in $(find . -name perf_counter.[ch]); do
M=$(echo $N | sed 's/perf_counter/perf_event/g')
mv $N $M
doneFILES=$(find . -name perf_event.*)
sed -i \
-e 's/COUNTER_MASK/REG_MASK/g' \
-e 's/COUNTER/EVENT/g' \
-e 's/\/event_id/g' \
-e 's/counter/event/g' \
-e 's/Counter/Event/g' \
$FILES... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.( NOTE: 'counters' are still the proper terminology when we deal
with hardware registers - and these sed scripts are a bit
over-eager in renaming them. I've undone some of that, but
in case there's something left where 'counter' would be
better than 'event' we can undo that on an individual basis
instead of touching an otherwise nicely automated patch. )Suggested-by: Stephane Eranian
Acked-by: Peter Zijlstra
Acked-by: Paul Mackerras
Reviewed-by: Arjan van de Ven
Cc: Mike Galbraith
Cc: Arnaldo Carvalho de Melo
Cc: Frederic Weisbecker
Cc: Steven Rostedt
Cc: Benjamin Herrenschmidt
Cc: David Howells
Cc: Kyle McMartin
Cc: Martin Schwidefsky
Cc: "David S. Miller"
Cc: Thomas Gleixner
Cc: "H. Peter Anvin"
Cc:
LKML-Reference:
Signed-off-by: Ingo Molnar
20 Sep, 2009
1 commit
-
Sam suggested moving STRIP_ASM_SYMS into the Kernel hacking menu
from the General Setup menu. It makes more sense there.Signed-off-by: Randy Dunlap
Signed-off-by: Andrew Morton
Signed-off-by: Sam Ravnborg
19 Sep, 2009
2 commits
-
Conflicts:
arch/x86/kernel/setup.c
drivers/acpi/power.c
init/main.cSigned-off-by: Len Brown
-
Now that the last users of markers have migrated to the event
tracer we can kill off the (now orphan) support code.Signed-off-by: Christoph Hellwig
Acked-by: Mathieu Desnoyers
Cc: Steven Rostedt
Cc: Frederic Weisbecker
LKML-Reference:
Signed-off-by: Ingo Molnar
18 Sep, 2009
1 commit
-
To quote Valdis:
This leaves somebody who has a laptop wondering which
choice is best for a system with only one or two cores that
has CONFIG_PREEMPT defined. One choice says it scales down
nicely, the other explicitly has a 'depends on PREEMPT'
attached to it...So add "scales down nicely" to TREE_PREEMPT_RCU to match that of
TREE_RCU.Suggested-by: Valdis Kletnieks
Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference:
Signed-off-by: Ingo Molnar
16 Sep, 2009
3 commits
-
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6:
Driver Core: devtmpfs - kernel-maintained tmpfs-based /dev
debugfs: Modify default debugfs directory for debugging pktcdvd.
debugfs: Modified default dir of debugfs for debugging UHCI.
debugfs: Change debugfs directory of IWMC3200
debugfs: Change debuhgfs directory of trace-events-sample.h
debugfs: Fix mount directory of debugfs by default in events.txt
hpilo: add poll f_op
hpilo: add interrupt handler
hpilo: staging for interrupt handling
driver core: platform_device_add_data(): use kmemdup()
Driver core: Add support for compatibility classes
uio: add generic driver for PCI 2.3 devices
driver-core: move dma-coherent.c from kernel to driver/base
mem_class: fix bug
mem_class: use minor as index instead of searching the array
driver model: constify attribute groups
UIO: remove 'default n' from Kconfig
Driver core: Add accessor for device platform data
Driver core: move dev_get/set_drvdata to drivers/base/dd.c
Driver core: add new device to bus's list before probing -
Devtmpfs lets the kernel create a tmpfs instance called devtmpfs
very early at kernel initialization, before any driver-core device
is registered. Every device with a major/minor will provide a
device node in devtmpfs.Devtmpfs can be changed and altered by userspace at any time,
and in any way needed - just like today's udev-mounted tmpfs.
Unmodified udev versions will run just fine on top of it, and will
recognize an already existing kernel-created device node and use it.
The default node permissions are root:root 0600. Proper permissions
and user/group ownership, meaningful symlinks, all other policy still
needs to be applied by userspace.If a node is created by devtmps, devtmpfs will remove the device node
when the device goes away. If the device node was created by
userspace, or the devtmpfs created node was replaced by userspace, it
will no longer be removed by devtmpfs.If it is requested to auto-mount it, it makes init=/bin/sh work
without any further userspace support. /dev will be fully populated
and dynamic, and always reflect the current device state of the kernel.
With the commonly used dynamic device numbers, it solves the problem
where static devices nodes may point to the wrong devices.It is intended to make the initial bootup logic simpler and more robust,
by de-coupling the creation of the inital environment, to reliably run
userspace processes, from a complex userspace bootstrap logic to provide
a working /dev.Signed-off-by: Kay Sievers
Signed-off-by: Jan Blunck
Tested-By: Harald Hoyer
Tested-By: Scott James Remnant
Signed-off-by: Greg Kroah-Hartman -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (46 commits)
powerpc64: convert to dynamic percpu allocator
sparc64: use embedding percpu first chunk allocator
percpu: kill lpage first chunk allocator
x86,percpu: use embedding for 64bit NUMA and page for 32bit NUMA
percpu: update embedding first chunk allocator to handle sparse units
percpu: use group information to allocate vmap areas sparsely
vmalloc: implement pcpu_get_vm_areas()
vmalloc: separate out insert_vmalloc_vm()
percpu: add chunk->base_addr
percpu: add pcpu_unit_offsets[]
percpu: introduce pcpu_alloc_info and pcpu_group_info
percpu: move pcpu_lpage_build_unit_map() and pcpul_lpage_dump_cfg() upward
percpu: add @align to pcpu_fc_alloc_fn_t
percpu: make @dyn_size mandatory for pcpu_setup_first_chunk()
percpu: drop @static_size from first chunk allocators
percpu: generalize first chunk allocator selection
percpu: build first chunk allocators selectively
percpu: rename 4k first chunk allocator to page
percpu: improve boot messages
percpu: fix pcpu_reclaim() locking
...Fix trivial conflict as by Tejun Heo in kernel/sched.c
12 Sep, 2009
1 commit
-
…/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (64 commits)
sched: Fix sched::sched_stat_wait tracepoint field
sched: Disable NEW_FAIR_SLEEPERS for now
sched: Keep kthreads at default priority
sched: Re-tune the scheduler latency defaults to decrease worst-case latencies
sched: Turn off child_runs_first
sched: Ensure that a child can't gain time over it's parent after fork()
sched: enable SD_WAKE_IDLE
sched: Deal with low-load in wake_affine()
sched: Remove short cut from select_task_rq_fair()
sched: Turn on SD_BALANCE_NEWIDLE
sched: Clean up topology.h
sched: Fix dynamic power-balancing crash
sched: Remove reciprocal for cpu_power
sched: Try to deal with low capacity, fix update_sd_power_savings_stats()
sched: Try to deal with low capacity
sched: Scale down cpu_power due to RT tasks
sched: Implement dynamic cpu_power
sched: Add smt_gain
sched: Update the cpu_power sum during load-balance
sched: Add SD_PREFER_SIBLING
...
04 Sep, 2009
2 commits
-
Ingo was getting warnings from rcu_scheduler_starting()
indicating that context switches had occurred before RCU ended
its special early-boot handling of grace periods.This is a dangerous condition, as it indicates that RCU might
have prematurely ended grace periods. This exploratory fix
moves rcu_scheduler_starting() earlier in boot.Reported-by: Ingo Molnar
Signed-off-by: Paul E. McKenney
Signed-off-by: Ingo Molnar -
Merge reason: Avoid fuzz in init/main.c and update from rc6 to rc8.
Signed-off-by: Ingo Molnar
29 Aug, 2009
1 commit
-
drivers/sfi/sfi_core.c contains the generic SFI implementation.
It has a private header, sfi_core.h, for its own use and the
private use of future files in drivers/sfi/Signed-off-by: Feng Tang
Signed-off-by: Len Brown
27 Aug, 2009
1 commit
-
Some architectures initialize clocks and timers in late_time_init and
x86 wants to do the same to avoid FIXMAP hackery for calibrating the
TSC. That would result in undefined sched_clock readout and wreckaged
printk timestamps again. We probably have those already on archs which
do all their time/clock setup in late_time_init.There is no harm to move that after late_time_init except that a few
more boot timestamps are stale. The scheduler is not active at that
point so no real wreckage is expected.Signed-off-by: Thomas Gleixner
LKML-Reference:
Cc: linux-arch@vger.kernel.org
26 Aug, 2009
1 commit
-
…nel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: Fix too large stack usage in do_one_initcall()
tracing: handle broken names in ftrace filter
ftrace: Unify effect of writing to trace_options and option/*
23 Aug, 2009
2 commits
-
Now that CONFIG_TREE_PREEMPT_RCU is in place, there is no
further need for CONFIG_PREEMPT_RCU. Remove it, along with
whatever subtle bugs it may (or may not) contain.Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference:
Signed-off-by: Ingo Molnar -
Create a kernel/rcutree_plugin.h file that contains definitions
for preemptable RCU (or, under the #else branch of the #ifdef,
empty definitions for the classic non-preemptable semantics).
These definitions fit into plugins defined in kernel/rcutree.c
for this purpose.This variant of preemptable RCU uses a new algorithm whose
read-side expense is roughly that of classic hierarchical RCU
under CONFIG_PREEMPT. This new algorithm's update-side expense
is similar to that of classic hierarchical RCU, and, in absence
of read-side preemption or blocking, is exactly that of classic
hierarchical RCU. Perhaps more important, this new algorithm
has a much simpler implementation, saving well over 1,000 lines
of code compared to mainline's implementation of preemptable
RCU, which will hopefully be retired in favor of this new
algorithm.The simplifications are obtained by maintaining per-task
nesting state for running tasks, and using a simple
lock-protected algorithm to handle accounting when tasks block
within RCU read-side critical sections, making use of lessons
learned while creating numerous user-level RCU implementations
over the past 18 months.Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference:
Signed-off-by: Ingo Molnar
21 Aug, 2009
1 commit
-
One of my testboxes triggered this nasty stack overflow crash
during SCSI probing:[ 5.874004] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 5.875004] device: 'sda': device_add
[ 5.878004] BUG: unable to handle kernel NULL pointer dereference at 00000a0c
[ 5.878004] IP: [] print_context_stack+0x81/0x110
[ 5.878004] *pde = 00000000
[ 5.878004] Thread overran stack, or stack corrupted
[ 5.878004] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[ 5.878004] last sysfs file:
[ 5.878004]
[ 5.878004] Pid: 1, comm: swapper Not tainted (2.6.31-rc6-tip-01272-g9919e28-dirty #5685)
[ 5.878004] EIP: 0060:[] EFLAGS: 00010083 CPU: 0
[ 5.878004] EIP is at print_context_stack+0x81/0x110
[ 5.878004] EAX: cf8a3000 EBX: cf8a3fe4 ECX: 00000049 EDX: 00000000
[ 5.878004] ESI: b1cfce84 EDI: 00000000 EBP: cf8a3018 ESP: cf8a2ff4
[ 5.878004] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
[ 5.878004] Process swapper (pid: 1, ti=cf8a2000 task=cf8a8000 task.ti=cf8a3000)
[ 5.878004] Stack:
[ 5.878004] b1004867 fffff000 cf8a3ffc
[ 5.878004] Call Trace:
[ 5.878004] [] ? kernel_thread_helper+0x7/0x10
[ 5.878004] BUG: unable to handle kernel NULL pointer dereference at 00000a0c
[ 5.878004] IP: [] print_context_stack+0x81/0x110
[ 5.878004] *pde = 00000000
[ 5.878004] Thread overran stack, or stack corrupted
[ 5.878004] Oops: 0000 [#2] PREEMPT SMP DEBUG_PAGEALLOCThe oops did not reveal any more details about the real stack
that we have and the system got into an infinite loop of
recursive pagefaults.So i booted with CONFIG_STACK_TRACER=y and the 'stacktrace' boot
parameter. The box did not crash (timings/conditions probably
changed a tiny bit to trigger the catastrophic crash), but the
/debug/tracing/stack_trace file was rather revealing:Depth Size Location (72 entries)
----- ---- --------
0) 3704 52 __change_page_attr+0xb8/0x290
1) 3652 24 __change_page_attr_set_clr+0x43/0x90
2) 3628 60 kernel_map_pages+0x108/0x120
3) 3568 40 prep_new_page+0x7d/0x130
4) 3528 84 get_page_from_freelist+0x106/0x420
5) 3444 116 __alloc_pages_nodemask+0xd7/0x550
6) 3328 36 allocate_slab+0xb1/0x100
7) 3292 36 new_slab+0x1c/0x160
8) 3256 36 __slab_alloc+0x133/0x2b0
9) 3220 4 kmem_cache_alloc+0x1bb/0x1d0
10) 3216 108 create_object+0x28/0x250
11) 3108 40 kmemleak_alloc+0x81/0xc0
12) 3068 24 kmem_cache_alloc+0x162/0x1d0
13) 3044 52 scsi_pool_alloc_command+0x29/0x70
14) 2992 20 scsi_host_alloc_command+0x22/0x70
15) 2972 24 __scsi_get_command+0x1b/0x90
16) 2948 28 scsi_get_command+0x35/0x90
17) 2920 24 scsi_setup_blk_pc_cmnd+0xd4/0x100
18) 2896 128 sd_prep_fn+0x332/0xa70
19) 2768 36 blk_peek_request+0xe7/0x1d0
20) 2732 56 scsi_request_fn+0x54/0x520
21) 2676 12 __generic_unplug_device+0x2b/0x40
22) 2664 24 blk_execute_rq_nowait+0x59/0x80
23) 2640 172 blk_execute_rq+0x6b/0xb0
24) 2468 32 scsi_execute+0xe0/0x140
25) 2436 64 scsi_execute_req+0x152/0x160
26) 2372 60 scsi_vpd_inquiry+0x6c/0x90
27) 2312 44 scsi_get_vpd_page+0x112/0x160
28) 2268 52 sd_revalidate_disk+0x1df/0x320
29) 2216 92 rescan_partitions+0x98/0x330
30) 2124 52 __blkdev_get+0x309/0x350
31) 2072 8 blkdev_get+0xf/0x20
32) 2064 44 register_disk+0xff/0x120
33) 2020 36 add_disk+0x6e/0xb0
34) 1984 44 sd_probe_async+0xfb/0x1d0
35) 1940 44 __async_schedule+0xf4/0x1b0
36) 1896 8 async_schedule+0x12/0x20
37) 1888 60 sd_probe+0x305/0x360
38) 1828 44 really_probe+0x63/0x170
39) 1784 36 driver_probe_device+0x5d/0x60
40) 1748 16 __device_attach+0x49/0x50
41) 1732 32 bus_for_each_drv+0x5b/0x80
42) 1700 24 device_attach+0x6b/0x70
43) 1676 16 bus_attach_device+0x47/0x60
44) 1660 76 device_add+0x33d/0x400
45) 1584 52 scsi_sysfs_add_sdev+0x6a/0x2c0
46) 1532 108 scsi_add_lun+0x44b/0x460
47) 1424 116 scsi_probe_and_add_lun+0x182/0x4e0
48) 1308 36 __scsi_add_device+0xd9/0xe0
49) 1272 44 ata_scsi_scan_host+0x10b/0x190
50) 1228 24 async_port_probe+0x96/0xd0
51) 1204 44 __async_schedule+0xf4/0x1b0
52) 1160 8 async_schedule+0x12/0x20
53) 1152 48 ata_host_register+0x171/0x1d0
54) 1104 60 ata_pci_sff_activate_host+0xf3/0x230
55) 1044 44 ata_pci_sff_init_one+0xea/0x100
56) 1000 48 amd_init_one+0xb2/0x190
57) 952 8 local_pci_probe+0x13/0x20
58) 944 32 pci_device_probe+0x68/0x90
59) 912 44 really_probe+0x63/0x170
60) 868 36 driver_probe_device+0x5d/0x60
61) 832 20 __driver_attach+0x89/0xa0
62) 812 32 bus_for_each_dev+0x5b/0x80
63) 780 12 driver_attach+0x1e/0x20
64) 768 72 bus_add_driver+0x14b/0x2d0
65) 696 36 driver_register+0x6e/0x150
66) 660 20 __pci_register_driver+0x53/0xc0
67) 640 8 amd_init+0x14/0x16
68) 632 572 do_one_initcall+0x2b/0x1d0
69) 60 12 do_basic_setup+0x56/0x6a
70) 48 20 kernel_init+0x84/0xce
71) 28 28 kernel_thread_helper+0x7/0x10There's a lot of fat functions on that stack trace, but
the largest of all is do_one_initcall(). This is due to
the boot trace entry variables being on the stack.Fixing this is relatively easy, initcalls are fundamentally
serialized, so we can move the local variables to file scope.Note that this large stack footprint was present for a
couple of months already - what pushed my system over
the edge was the addition of kmemleak to the call-chain:6) 3328 36 allocate_slab+0xb1/0x100
7) 3292 36 new_slab+0x1c/0x160
8) 3256 36 __slab_alloc+0x133/0x2b0
9) 3220 4 kmem_cache_alloc+0x1bb/0x1d0
10) 3216 108 create_object+0x28/0x250
11) 3108 40 kmemleak_alloc+0x81/0xc0
12) 3068 24 kmem_cache_alloc+0x162/0x1d0
13) 3044 52 scsi_pool_alloc_command+0x29/0x70This pushes the total to ~3800 bytes, only a tiny bit
more was needed to corrupt the on-kernel-stack thread_info.The fix reduces the stack footprint from 572 bytes
to 28 bytes.Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Frederic Weisbecker
Cc: Steven Rostedt
Cc: Catalin Marinas
Cc: Jens Axboe
Cc: Linus Torvalds
Cc:
LKML-Reference:
Signed-off-by: Ingo Molnar
16 Aug, 2009
1 commit
-
Merge reason: the branch was on pre-rc1 .30, update to latest.
Signed-off-by: Ingo Molnar
14 Aug, 2009
2 commits
-
Conflicts:
arch/sparc/kernel/smp_64.c
arch/x86/kernel/cpu/perf_counter.c
arch/x86/kernel/setup_percpu.c
drivers/cpufreq/cpufreq_ondemand.c
mm/percpu.cConflicts in core and arch percpu codes are mostly from commit
ed78e1e078dd44249f88b1dd8c76dafb39567161 which substituted many
num_possible_cpus() with nr_cpu_ids. As for-next branch has moved all
the first chunk allocators into mm/percpu.c, the changes are moved
from arch code to mm/percpu.c.Signed-off-by: Tejun Heo
-
nr_cpu_ids is dependent only on cpu_possible_map and
setup_per_cpu_areas() already depends on cpu_possible_map and will use
nr_cpu_ids. Initialize nr_cpu_ids before setting up percpu areas.Signed-off-by: Tejun Heo
05 Aug, 2009
1 commit
-
If user has already enabled profiling support in the kernel
(for oprofile, old-style profiling of ftrace) then offer up
perfcounters with a y default in interactive kconfig sessions.Still keep it off by default otherwise.
Cc: Peter Zijlstra
Cc: Linus Torvalds
Signed-off-by: Ingo Molnar
02 Aug, 2009
1 commit
-
Explain what tracepoint profiling sources are about.
Signed-off-by: Peter Zijlstra
Acked-by: Jeff Garzik
LKML-Reference:
Signed-off-by: Ingo Molnar
13 Jul, 2009
1 commit
-
Fix a missed rename in EVENT_PROFILE support so that it gets
built and allows tracepoint tracing from the 'perf' tool.Fix a typo in the (never before built & enabled) portion in
perf_counter.c as well, and update that code to the
attr.config changes as well.Signed-off-by: Chris Wilson
Cc: Ben Gamari
Cc: Jason Baron
Cc: Frederic Weisbecker
Cc: Mike Galbraith
Cc: Peter Zijlstra
Cc: Paul Mackerras
Cc: Steven Rostedt
LKML-Reference:
Signed-off-by: Ingo Molnar
04 Jul, 2009
1 commit
-
Pull linus#master to merge PER_CPU_DEF_ATTRIBUTES and alpha build fix
changes. As alpha in percpu tree uses 'weak' attribute instead of
inline assembly, there's no need for __used attribute.Conflicts:
arch/alpha/include/asm/percpu.h
arch/mn10300/kernel/vmlinux.lds.S
include/linux/percpu-defs.h
24 Jun, 2009
3 commits
-
Remove Classic RCU, given that the combination of Tree RCU and
the proposed Bloatwatch RCU do everything that Classic RCU can
with fewer bugs.Tree RCU has been default in x86 builds for almost six months,
and seems to be quite reliable, so there does not seem to be
much justification for keeping the Classic RCU code and config
complexity around anymore.Signed-off-by: Paul E. McKenney
Cc: akpm@linux-foundation.org
Cc: niv@us.ibm.com
Cc: dvhltc@us.ibm.com
Cc: dipankar@in.ibm.com
Cc: dhowells@redhat.com
Cc: lethal@linux-sh.org
Cc: kernel@wantstofly.org
Signed-off-by: Ingo Molnar -
This patch makes most !CONFIG_HAVE_SETUP_PER_CPU_AREA archs use
dynamic percpu allocator. The first chunk is allocated using
embedding helper and 8k is reserved for modules. This ensures that
the new allocator behaves almost identically to the original allocator
as long as static percpu variables are concerned, so it shouldn't
introduce much breakage.s390 and alpha use custom SHIFT_PERCPU_PTR() to work around addressing
range limit the addressing model imposes. Unfortunately, this breaks
if the address is specified using a variable, so for now, the two
archs aren't converted.The following architectures are affected by this change.
* sh
* arm
* cris
* mips
* sparc(32)
* blackfin
* avr32
* parisc (broken, under investigation)
* m32r
* powerpc(32)As this change makes the dynamic allocator the default one,
CONFIG_HAVE_DYNAMIC_PER_CPU_AREA is replaced with its invert -
CONFIG_HAVE_LEGACY_PER_CPU_AREA, which is added to yet-to-be converted
archs. These archs implement their own setup_per_cpu_areas() and the
conversion is not trivial.* powerpc(64)
* sparc(64)
* ia64
* alpha
* s390Boot and batch alloc/free tests on x86_32 with debug code (x86_32
doesn't use default first chunk initialization). Compile tested on
sparc(32), powerpc(32), arm and alpha.Kyle McMartin reported that this change breaks parisc. The problem is
still under investigation and he is okay with pushing this patch
forward and fixing parisc later.[ Impact: use dynamic allocator for most archs w/o custom percpu setup ]
Signed-off-by: Tejun Heo
Acked-by: Rusty Russell
Acked-by: David S. Miller
Acked-by: Benjamin Herrenschmidt
Acked-by: Martin Schwidefsky
Reviewed-by: Christoph Lameter
Cc: Paul Mundt
Cc: Russell King
Cc: Mikael Starvik
Cc: Ralf Baechle
Cc: Bryan Wu
Cc: Kyle McMartin
Cc: Matthew Wilcox
Cc: Grant Grundler
Cc: Hirokazu Takata
Cc: Richard Henderson
Cc: Ivan Kokshaysky
Cc: Heiko Carstens
Cc: Ingo Molnar -
…bugzilla-13121', 'bugzilla-13396', 'bugzilla-13533', 'bugzilla-13612', 'c3_lock', 'hid-cleanups', 'misc-2.6.31', 'pdc-leak-fix', 'pnpacpi', 'power_nocheck', 'thinkpad_acpi', 'video' and 'wmi' into release