* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
Revert "net: Make accesses to ->br_port safe for sparse RCU"
mce: convert to rcu_dereference_index_check()
net: Make accesses to ->br_port safe for sparse RCU
vfs: add fs.h to define struct file
lockdep: Add an in_workqueue_context() lockdep-based test function
rcu: add __rcu API for later sparse checking
rcu: add an rcu_dereference_index_check()
tree/tiny rcu: Add debug RCU head objects
mm: remove all rcu head initializations
fs: remove all rcu head initializations, except on_stack initializations
powerpc: remove all rcu head initializations
Power limit notification feature is published in Intel 64 and IA-32
Architectures SDMV Vol 3A 14.5.6 Power Limit Notification.
It is implemented first on Intel Sandy Bridge platform.
The patch handles notification interrupt. Interrupt handler dumps power limit
information in log_buf, logs the event in mce log, and increases the event
counters (core_power_limit and package_power_limit). Upper level applications
could use the data to detect system health or diagnose functionality/performance
issues.
In the future, the event could be handled in a more fancy way.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
LKML-Reference: <1280448826-12004-5-git-send-email-fenghua.yu@intel.com>
Reviewed-by: Len Brown <len.brown@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Add package level thermal throttle interrupt support. The interrupt handler
increases package level thermal throttle count. It also logs the event in MCE
log.
The package level thermal throttle interrupt happens across threads in a
package. Each thread handles the interrupt individually. User level application
is supposed to retrieve correct event count and log based on package/thread
topology. This is the same situation for core level interrupt handler. In the
future, interrupt may be reported only per package or per core.
core_throttle_count and package_throttle_count are used for user interface.
Previously only throttle_count is used for core throttle count. If you think
new core_throttle_count name breaks user interface, I can change this part.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
LKML-Reference: <1280448826-12004-4-git-send-email-fenghua.yu@intel.com>
Reviewed-by: Len Brown <len.brown@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The mce processing applies rcu_dereference_check() to integers used as
array indices. This patch therefore moves mce to the new RCU API
rcu_dereference_index_check() that avoids the sparse processing that
would otherwise result in compiler errors.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Use HW_ERR printk prefix in MCE handler. To make it more explicit that
this is hardware error instead of software error.
Signed-off-by: Huang Ying <ying.huang@intel.com>
LKML-Reference: <1275978939.3444.668.camel@yhuang-dev.sh.intel.com>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
It is reported that CMCI is not raised when number of corrected error
reaches preset threshold. After inspection, it is found that
MSR_IA32_MCI_CTL2 threshold field is not setup properly. This patch
fixed it.
Value of MCI_CTL2_CMCI_THRESHOLD_MASK is fixed according to x86_64
Software Developer's Manual too.
Reported-by: Shaohui Zheng <shaohui.zheng@intel.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
LKML-Reference: <1275977350.3444.660.camel@yhuang-dev.sh.intel.com>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Rename CMCI_EN to MCI_CTL2_CMCI_EN and CMCI_THRESHOLD_MASK to
MCI_CTL2_CMCI_THRESHOLD_MASK to make naming consistent.
Signed-off-by: Huang Ying <ying.huang@intel.com>
LKML-Reference: <1275977348.3444.659.camel@yhuang-dev.sh.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* 'linux_next' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/i7core: (83 commits)
i7core_edac: Better describe the supported devices
Add support for Westmere to i7core_edac driver
i7core_edac: don't free on success
i7core_edac: Add support for X5670
Always call i7core_[ur]dimm_check_mc_ecc_err
i7core_edac: fix memory leak of i7core_dev
EDAC: add __init to i7core_xeon_pci_fixup
i7core_edac: Fix wrong device id for channel 1 devices
i7core: add support for Lynnfield alternate address
i7core_edac: Add initial support for Lynnfield
i7core_edac: do not export static functions
edac: fix i7core build
edac: i7core_edac produces undefined behaviour on 32bit
i7core_edac: Use a more generic approach for probing PCI devices
i7core_edac: PCI device is called NONCORE, instead of NOCORE
i7core_edac: Fix ringbuffer maxsize
i7core_edac: First store, then increment
i7core_edac: Better parse "any" addrmask
i7core_edac: Use a lockless ringbuffer
edac: Create an unique instance for each kobj
...
By the previous modification, the cpu notifier can return encapsulate
errno value. This converts the cpu notifiers for msr, cpuid, and
therm_throt.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
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>
Traditionally, fatal MCE will cause Linux print error log to console
then reboot. Because MCE registers will preserve their content after
warm reboot, the hardware error can be logged to disk or network after
reboot. But system may fail to warm reboot, then you may lose the
hardware error log. ERST can help here. Through saving the hardware
error log into flash via ERST before go panic, the hardware error log
can be gotten from the flash after system boot successful again.
The fatal MCE processing procedure with ERST involved is as follow:
- Hardware detect error, MCE raised
- MCE read MCE registers, check error severity (fatal), prepare error record
- Write MCE error record into flash via ERST
- Go panic, then trigger system reboot
- System reboot, /sbin/mcelog run, it reads /dev/mcelog to check flash
for error record of previous boot via ERST, and output and clear
them if available
- /sbin/mcelog logs error records into disk or network
ERST only accepts CPER record format, but there is no pre-defined CPER
section can accommodate all information in struct mce, so a customized
section type is defined to hold struct mce inside a CPER record as an
error section.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Generic Hardware Error Source provides a way to report platform
hardware errors (such as that from chipset). It works in so called
"Firmware First" mode, that is, hardware errors are reported to
firmware firstly, then reported to Linux by firmware. This way, some
non-standard hardware error registers or non-standard hardware link
can be checked by firmware to produce more valuable hardware error
information for Linux.
Now, only SCI notification type and memory errors are supported. More
notification type and hardware error type will be added later. These
memory errors are reported to user space through /dev/mcelog via
faking a corrected Machine Check, so that the error memory page can be
offlined by /sbin/mcelog if the error count for one page is beyond the
threshold.
On some machines, Machine Check can not report physical address for
some corrected memory errors, but GHES can do that. So this simplified
GHES is implemented firstly.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
edac_mce module is an interface module that gets mcelog data and
forwards to any registered edac module that expects to receive data via
mce.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Commit f56e8a076 "x86/mce: Fix RCU lockdep splats" introduced the
following build bug:
arch/x86/kernel/cpu/mcheck/mce.c: In function 'mce_log':
arch/x86/kernel/cpu/mcheck/mce.c:166: error: 'mce_read_mutex' undeclared (first use in this function)
arch/x86/kernel/cpu/mcheck/mce.c:166: error: (Each undeclared identifier is reported only once
arch/x86/kernel/cpu/mcheck/mce.c:166: error: for each function it appears in.)
Move the in-the-middle-of-file lock variable up to the variable
definition section, the top of the .c file.
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
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: <1267830207-9474-3-git-send-email-paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, k8 nb: Fix boot crash: enable k8_northbridges unconditionally on AMD systems
x86, UV: Fix target_cpus() in x2apic_uv_x.c
x86: Reduce per cpu warning boot up messages
x86: Reduce per cpu MCA boot up messages
x86_64, cpa: Don't work hard in preserving kernel 2M mappings when using 4K already
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
locking: Make sparse work with inline spinlocks and rwlocks
x86/mce: Fix RCU lockdep splats
rcu: Increase RCU CPU stall timeouts if PROVE_RCU
ftrace: Replace read_barrier_depends() with rcu_dereference_raw()
rcu: Suppress RCU lockdep warnings during early boot
rcu, ftrace: Fix RCU lockdep splat in ftrace_perf_buf_prepare()
rcu: Suppress __mpol_dup() false positive from RCU lockdep
rcu: Make rcu_read_lock_sched_held() handle !PREEMPT
rcu: Add control variables to lockdep_rcu_dereference() diagnostics
rcu, cgroup: Relax the check in task_subsys_state() as early boot is now handled by lockdep-RCU
rcu: Use wrapper function instead of exporting tasklist_lock
sched, rcu: Fix rcu_dereference() for RCU-lockdep
rcu: Make task_subsys_state() RCU-lockdep checks handle boot-time use
rcu: Fix holdoff for accelerated GPs for last non-dynticked CPU
x86/gart: Unexport gart_iommu_aperture
Fix trivial conflicts in kernel/trace/ftrace.c
These are the non-static sysfs attributes that exist on
my test machine. Fix them to use sysfs_attr_init or
sysfs_bin_attr_init as appropriate. It simply requires
making a sysfs attribute present to see this. So this
is a little bit tedious but otherwise not too bad.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Constify struct sysfs_ops.
This is part of the ops structure constification
effort started by Arjan van de Ven et al.
Benefits of this constification:
* prevents modification of data that is shared
(referenced) by many other structure instances
at runtime
* detects/prevents accidental (but not intentional)
modification attempts on archs that enforce
read-only kernel data at runtime
* potentially better optimized code as the compiler
can assume that the const data cannot be changed
* the compiler/linker move const data into .rodata
and therefore exclude them from false sharing
Signed-off-by: Emese Revfy <re.emese@gmail.com>
Acked-by: David Teigland <teigland@redhat.com>
Acked-by: Matt Domsch <Matt_Domsch@dell.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Acked-by: Hans J. Koch <hjk@linutronix.de>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
It looks better to have a common function. No change in functionality.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <4B25FDDC.407@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Add check if APIC is not disabled since thermal
monitoring depends on it. As only apic gets disabled
we should not try to install "thermal monitor" vector,
print out that thermal monitoring is enabled and etc...
Note that "Intel Correct Machine Check Interrupts" already
has such a check.
Also I decided to not add cpu_has_apic check into
mcheck_intel_therm_init since even if it'll call apic_read on
disabled apic -- it's safe here and allow us to save a few code
bytes.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
LKML-Reference: <4B25FDC2.3020401@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When there are a large number of processors in a system, there
is an excessive amount of messages sent to the system console.
It's estimated that with 4096 processors in a system, and the
console baudrate set to 56K, the startup messages will take
about 84 minutes to clear the serial port.
This set of patches limits the number of repetitious messages
which contain no additional information. Much of this information
is obtainable from the /proc and /sysfs. Some of the messages
are also sent to the kernel log buffer as KERN_DEBUG messages so
dmesg can be used to examine more closely any details specific to
a problem.
The new cpu bootup sequence for system_state == SYSTEM_BOOTING:
Booting Node 0, Processors #1#2#3#4#5#6#7 Ok.
Booting Node 1, Processors #8#9#10#11#12#13#14#15 Ok.
...
Booting Node 3, Processors #56#57#58#59#60#61#62#63 Ok.
Brought up 64 CPUs
After the system is running, a single line boot message is displayed
when CPU's are hotplugged on:
Booting Node %d Processor %d APIC 0x%x
Status of the following lines:
CPU: Physical Processor ID: printed once (for boot cpu)
CPU: Processor Core ID: printed once (for boot cpu)
CPU: Hyper-Threading is disabled printed once (for boot cpu)
CPU: Thermal monitoring enabled printed once (for boot cpu)
CPU %d/0x%x -> Node %d: removed
CPU %d is now offline: only if system_state == RUNNING
Initializing CPU#%d: KERN_DEBUG
Signed-off-by: Mike Travis <travis@sgi.com>
LKML-Reference: <4B219E28.8080601@sgi.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Commit cebe182033 had an unnecessary,
wrong change: &mce_banks[i].attr is equivalent to the former
bank_attrs[i], not to mce_attrs[i].
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Acked-by: Andi Kleen <andi@firstfloor.org>
LKML-Reference: <4B1E05CC.4040703@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
mce_timer must be passed to setup_timer() in all cases, no
matter whether it is going to be actually used. Otherwise, when
the CPU gets brought down, its call to del_timer_sync() will
never return, as the timer won't have a base associated, and
hence lock_timer_base() will loop infinitely.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: <stable@kernel.org>
LKML-Reference: <4B1DB831.2030801@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Even it is in error path unlikely taken, add_timer_on() at
CPU_DOWN_FAILED* needs to be skipped if mce_timer is disabled.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Jan Beulich <jbeulich@novell.com>
Cc: <stable@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
The mce_disable_cpu() and mce_reenable_cpu() are called only
from mce_cpu_callback() which is marked as __cpuinit.
So these functions can be __cpuinit too.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <4B0E3C4E.4090809@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The intel_init_thermal() is called from resume path, so it
cannot be marked as __init.
OTOH mce_banks_init() is only called from
__mcheck_cpu_cap_init() which is marked as __cpuinit, so it can
be also marked as __cpuinit.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Acked-by: Yong Wang <yong.y.wang@linux.intel.com>
LKML-Reference: <4AFBB0B8.2070501@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mark the thermal init functions __init so that the init memory
can be freed.
Signed-off-by: Yong Wang <yong.y.wang@intel.com>
LKML-Reference: <20091111075125.GA17900@ywang-moblin2.bj.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On platforms where the BIOS handles the thermal monitor interrupt,
APIC_LVTTHMR on each logical CPU is programmed to generate a SMI
and OS must not touch it.
Unfortunately AP bringup sequence using INIT-SIPI-SIPI clears all
the LVT entries except the mask bit. Essentially this results in
all LVT entries including the thermal monitoring interrupt set
to masked (clearing the bios programmed value for APIC_LVTTHMR).
And this leads to kernel take over the thermal monitoring
interrupt on AP's but not on BSP (leaving the bios programmed
value only on BSP).
As a result of this, we have seen system hangs when the thermal
monitoring interrupt is generated.
Fix this by reading the initial value of thermal LVT entry on
BSP and if bios has taken over the control, then program the
same value on all AP's and leave the thermal monitoring
interrupt control on all the logical cpu's to the bios.
Signed-off-by: Yong Wang <yong.y.wang@intel.com>
Reviewed-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Arjan van de Ven <arjan@infradead.org>
LKML-Reference: <20091110013824.GA24940@ywang-moblin2.bj.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: stable@kernel.org
Note that there's no freeing the cpu var, since this module has
no unload function.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Huang Ying <ying.huang@intel.com>
LKML-Reference: <200911031458.30987.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Prefix global/setup routines with "mcheck_" thus differentiating
from the internal facilities prefixed with "mce_". Also, prefix
the per cpu calls with mcheck_cpu and rename them to reflect the
MCE setup hierarchy of calls better.
There should be no functionality change resulting from this
patch.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: Andi Kleen <andi@firstfloor.org>
LKML-Reference: <1255689093-26921-1-git-send-email-borislav.petkov@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The MCE initialization code explicitly says it doesn't handle
asymmetric configurations where different CPUs support different
numbers of MCE banks, and it prints a big warning in that case.
Therefore, printing the "mce: CPU supports <x> MCE banks"
message into the kernel log for every CPU is pure redundancy
that clutters the log significantly for systems with lots of
CPUs.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
LKML-Reference: <adaeip473qt.fsf@cisco.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This approach is the first baby step towards solving many of the
structural problems the x86 MCE logging code is having today:
- It has a private ring-buffer implementation that has a number
of limitations and has been historically fragile and buggy.
- It is using a quirky /dev/mcelog ioctl driven ABI that is MCE
specific. /dev/mcelog is not part of any larger logging
framework and hence has remained on the fringes for many years.
- The MCE logging code is still very unclean partly due to its ABI
limitations. Fields are being reused for multiple purposes, and
the whole message structure is limited and x86 specific to begin
with.
All in one, the x86 tree would like to move away from this private
implementation of an event logging facility to a broader framework.
By using perf events we gain the following advantages:
- Multiple user-space agents can access MCE events. We can have an
mcelog daemon running but also a system-wide tracer capturing
important events in flight-recorder mode.
- Sampling support: the kernel and the user-space call-chain of MCE
events can be stored and analyzed as well. This way actual patterns
of bad behavior can be matched to precisely what kind of activity
happened in the kernel (and/or in the app) around that moment in
time.
- Coupling with other hardware and software events: the PMU can track a
number of other anomalies - monitoring software might chose to
monitor those plus the MCE events as well - in one coherent stream of
events.
- Discovery of MCE sources - tracepoints are enumerated and tools can
act upon the existence (or non-existence) of various channels of MCE
information.
- Filtering support: we just subscribe to and act upon the events we
are interested in. Then even on a per event source basis there's
in-kernel filter expressions available that can restrict the amount
of data that hits the event channel.
- Arbitrary deep per cpu buffering of events - we can buffer 32
entries or we can buffer as much as we want, as long as we have
the RAM.
- An NMI-safe ring-buffer implementation - mappable to user-space.
- Built-in support for timestamping of events, PID markers, CPU
markers, etc.
- A rich ABI accessible over system call interface. Per cpu, per task
and per workload monitoring of MCE events can be done this way. The
ABI itself has a nice, meaningful structure.
- Extensible ABI: new fields can be added without breaking tooling.
New tracepoints can be added as the hardware side evolves. There's
various parsers that can be used.
- Lots of scheduling/buffering/batching modes of operandi for MCE
events. poll() support. mmap() support. read() support. You name it.
- Rich tooling support: even without any MCE specific extensions added
the 'perf' tool today offers various views of MCE data: perf report,
perf stat, perf trace can all be used to view logged MCE events and
perhaps correlate them to certain user-space usage patterns. But it
can be used directly as well, for user-space agents and policy action
in mcelog, etc.
With this we hope to achieve significant code cleanup and feature
improvements in the MCE code, and we hope to be able to drop the
/dev/mcelog facility in the end.
This patch is just a plain dumb dump of mce_log() records to
the tracepoints / perf events framework - a first proof of
concept step.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <4AD42A0D.7050104@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add an atomic notifier which ensures proper locking when conveying
MCE info to EDAC for decoding. The actual notifier call overrides a
default, negative priority notifier.
Note: make sure we register the default decoder only once since
mcheck_init() runs on each CPU.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <20091003065752.GA8935@liondog.tnic>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Make decoding of MCEs happen only on AMD hardware by registering a
non-default callback only on CPU families which support it.
While looking at the interaction of decode_mce() with the other MCE
code i also noticed a few other things and made the following
cleanups/fixes:
- Fixed the mce_decode() weak alias - a weak alias is really not
good here, it should be a proper callback. A weak alias will be
overriden if a piece of code is built into the kernel - not
good, obviously.
- The patch initializes the callback on AMD family 10h and 11h.
- Added the more correct fallback printk of:
No support for human readable MCE decoding on this CPU type.
Transcribe the message and run it through 'mcelog --ascii' to decode.
On CPUs that dont have a decoder.
- Made the surrounding code more readable.
Note that the callback allows us to have a default fallback -
without having to check the CPU versions during the printout
itself. When an EDAC module registers itself, it can install the
decode-print function.
(there's no unregister needed as this is core code.)
version -v2 by Borislav Petkov:
- add K8 to the set of supported CPUs
- always build in edac_mce_amd since we use an early_initcall now
- fix checkpatch warnings
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andi Kleen <andi@firstfloor.org>
LKML-Reference: <20091001141432.GA11410@aftab>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This reverts commit 22223c9b41, as
requested by Andi Kleen:
"Obviously kernels compiled with AMD support can still run on non AMD
systems, so messages like this can never be removed at compile time."
Requsted-by: Andi Kleen <andi@firstfloor.org>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use rdmsrl_safe() when accessing MCE registers. While in
theory we always 'know' which ones are safe to access from
the capability bits, there's a lot of hardware variations
and reality might differ from theory, as it did in this case:
http://bugzilla.kernel.org/show_bug.cgi?id=14204
[ 0.010016] mce: CPU supports 5 MCE banks
[ 0.011029] general protection fault: 0000 [#1]
[ 0.011998] last sysfs file:
[ 0.011998] Modules linked in:
[ 0.011998]
[ 0.011998] Pid: 0, comm: swapper Not tainted (2.6.31_router #1) HP Vectra
[ 0.011998] EIP: 0060:[<c100d9b9>] EFLAGS: 00010246 CPU: 0
[ 0.011998] EIP is at mce_rdmsrl+0x19/0x60
[ 0.011998] EAX: 00000000 EBX: 00000001 ECX: 00000407 EDX: 08000000
[ 0.011998] ESI: 00000000 EDI: 8c000000 EBP: 00000405 ESP: c17d5eac
So WARN_ONCE() instead of crashing the box.
( also fix a number of stylistic inconsistencies in the code. )
Note, we might still crash in wrmsrl() if we get that far, but
we shouldnt if the registers are truly inaccessible.
Reported-by: GNUtoo <GNUtoo@no-log.org>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <bug-14204-5438@http.bugzilla.kernel.org/>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Current raise_local() uses a struct mce that comes from mce_write()
as a parameter instead of the real inject-msg, so when we set
mce.finished = 0 to clear injected MCE, the real inject stays
valid.
This will cause the remaining inject-msg affect the next injection,
which is not desired.
To fix this, real inject-msg is used in raise_local instead of the
one on the stack.
This patch is based on the diagnosis and the fixes by Dean Nelson.
Reported-by: Dean Nelson <dnelson@redhat.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <1253601357.15717.757.camel@yhuang-dev.sh.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If a system switches back and forth between hot and cold mode,
the MCE code will print a stream of critical kernel messages.
Extend the throttling code to properly notice this, by
only printing the first hot + cold transition and omitting
the rest up to CHECK_INTERVAL (5 minutes).
This way we'll only get a single incident of:
[ 102.356584] CPU0: Temperature above threshold, cpu clock throttled (total events = 1)
[ 102.357000] Disabling lock debugging due to kernel taint
[ 102.369223] CPU0: Temperature/speed normal
Every 5 minutes. The 'total events' count tells the number of cold/hot
transitions detected, should overheating occur after 5 minutes again:
[ 402.357580] CPU0: Temperature above threshold, cpu clock throttled (total events = 24891)
[ 402.358001] CPU0: Temperature/speed normal
[ 450.704142] Machine check events logged
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
