Impact: Major new feature
Intel CMCI (Corrected Machine Check Interrupt) is a new
feature on Nehalem CPUs. It allows the CPU to trigger
interrupts on corrected events, which allows faster
reaction to them instead of with the traditional
polling timer.
Also use CMCI to discover shared banks. Machine check banks
can be shared by CPU threads or even cores. Using the CMCI enable
bit it is possible to detect the fact that another CPU already
saw a specific bank. Use this to assign shared banks only
to one CPU to avoid reporting duplicated events.
On CPU hot unplug bank sharing is re discovered. This is done
using a thread that cycles through all the CPUs.
To avoid races between the poller and CMCI we only poll
for banks that are not CMCI capable and only check CMCI
owned banks on a interrupt.
The shared banks ownership information is currently only used for
CMCI interrupts, not polled banks.
The sharing discovery code follows the algorithm recommended in the
IA32 SDM Vol3a 14.5.2.1
The CMCI interrupt handler just calls the machine check poller to
pick up the machine check event that caused the interrupt.
I decided not to implement a separate threshold event like
the AMD version has, because the threshold is always one currently
and adding another event didn't seem to add any value.
Some code inspired by Yunhong Jiang's Xen implementation,
which was in term inspired by a earlier CMCI implementation
by me.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Define a per cpu bitmap that contains the banks polled by the machine
check poller. This is needed for the CMCI code in the next patches
to be able to disable polling on specific banks.
The bank by default contains all banks, so there is no behaviour
change. Only future code will remove some banks from the polling
set.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: behavior change, use common code
Use a standard leaky bucket ratelimit for the machine check
warning print interval instead of waiting every check_interval.
Also decrease the limit to twice per minute.
This interacts better with threshold interrupts because
they can happen more often than check_interval.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: minor bugfix
The threshold handler on AMD (and soon on Intel) could be theoretically
reentered by the hardware. This could lead to corrupted events
because the machine check poll code assumes it is not reentered.
Move the APIC ACK to the end of the interrupt handler to let
the hardware avoid that.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: cleanup; preparation for feature
The mce_amd_64 code has an own private MC threshold vector with an own
interrupt handler. Since Intel needs a similar handler
it makes sense to share the vector because both can not
be active at the same time.
I factored the common APIC handler code into a separate file which can
be used by both the Intel or AMD MC code.
This is needed for the next patch which adds an Intel specific
CMCI handler.
This patch should be a nop for AMD, it just moves some code
around.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Cleanup (code movement)
Move MAX_NR_BANKS into mce.h because it's needed there
for followup patches.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Bug fix when CPU hotplug is disabled
Correct the following broken __cpuinit/__cpuexit annotations:
- mce_cpu_features() is called from mce_resume(), and so cannot be
__cpuinit.
- mce_disable_cpu() and mce_reenable_cpu() are called from
mce_cpu_callback(), and so cannot be __cpuexit().
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: Bug fix on UP
Checkin 6ec68bff3c:
x86, mce: reinitialize per cpu features on resume
introduced a call to mce_cpu_features() in the resume path, in order
for the MCE machinery to get properly reinitialized after a resume.
However, this function (and its successors) was flagged __cpuinit,
which becomes __init on UP configurations (on SMP suspend/resume
requires CPU hotplug and so this would not be seen.)
Remove the offending __cpuinit annotations for mce_cpu_features() and
its successor functions.
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Cleanup
The standard spelling of a printf pattern for long long is "ll", not
"L", which is for long double.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup, performance enhancement
The machine check poller is diverging more and more from the fatal
exception handler. Instead of adding more special cases separate the code
paths completely. The corrected poll path is actually quite simple,
and this doesn't result in much code duplication.
This makes both handlers much easier to read and results in
cleaner code flow. The exception handler now only needs to care
about uncorrected errors, which also simplifies the handling of multiple
errors. The corrected poller also now always runs in standard interrupt
context and does not need to do anything special to handle NMI context.
Minor behaviour changes:
- MCG status is now not cleared on polling.
- Only the banks which had corrected errors get cleared on polling
- The exception handler only clears banks with errors now
v2: Forward port to new patch order. Add "uc" argument.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup
This merely factors out duplicated code to set up
the initial struct mce state into a single function.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup; making code future proof; memory saving on small systems
This patch replaces the hardcoded max number of machine check banks with
dynamic allocation depending on what the CPU reports. The sysfs
data structures and the banks array are dynamically allocated.
There is still a hard bank limit (128) because the mcelog protocol uses
banks >= 128 as pseudo banks to escape other events. But we expect
that 128 banks is beyond any reasonable CPU for now.
This supersedes an earlier patch by Venki, but it solves the problem
more completely by making the limit fully dynamic (up to the 128
boundary).
This saves some memory on machines with less than 6 banks because
they won't need sysdevs for unused ones and also allows to
use sysfs to control these banks on possible future CPUs with
more than 6 banks.
This is an updated patch addressing Venki's comments. I also added in
another patch from Thomas which fixed the error allocation path (that
patch was previously separated)
Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: bugfix
Considering the situation as follow:
before: mcelog.next == 1, mcelog.entry[0].finished = 1
+--------------------------------------------------------------------------
R W1 W2 W3
read mcelog.next (1)
mcelog.next++ (2)
(working on entry 1,
finished == 0)
mcelog.next = 0
mcelog.next++ (1)
(working on entry 0)
mcelog.next++ (2)
(working on entry 1)
<----------------- race ---------------->
(done on entry 1,
finished = 1)
(done on entry 1,
finished = 1)
To fix the race condition, a cmpxchg loop is added to mce_read() to
ensure no new MCE record can be added between mcelog.next reading and
mcelog.next = 0.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Lower priority bug fix
Offlined CPUs could still get machine checks, but the machine check handler
cannot handle them properly, leading to an unconditional crash. Disable
machine checks on CPUs that are going down.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: bug fix, in this case the resume handler shouldn't run which
avoids incorrectly reenabling machine checks on resume
When MCEs are completely disabled on the command line don't set
up the sysdev devices for them either.
Includes a comment fix from Thomas Gleixner.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Higher priority bug fix
The machine check poller runs a single timer and then broadcasted an
IPI to all CPUs to check them. This leads to unnecessary
synchronization between CPUs. The original CPU running the timer has
to wait potentially a long time for all other CPUs answering. This is
also real time unfriendly and in general inefficient.
This was especially a problem on systems with a lot of events where
the poller run with a higher frequency after processing some events.
There could be more and more CPU time wasted with this, to
the point of significantly slowing down machines.
The machine check polling is actually fully independent per CPU, so
there's no reason to not just do this all with per CPU timers. This
patch implements that.
Also switch the poller also to use standard timers instead of work
queues. It was using work queues to be able to execute a user program
on a event, but mce_notify_user() handles this case now with a
separate callback. So instead always run the poll code in in a
standard per CPU timer, which means that in the common case of not
having to execute a trigger there will be less overhead.
This allows to clean up the initialization significantly, because
standard timers are already up when machine checks get init'ed. No
multiple initialization functions.
Thanks to Thomas Gleixner for some help.
Cc: thockin@google.com
v2: Use del_timer_sync() on cpu shutdown and don't try to handle
migrated timers.
v3: Add WARN_ON for timer running on unexpected CPU
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Needed for bug fix in next patch
This relaxes the requirement that mce_notify_user has to run in process
context. Useful for future changes, but also leads to cleaner
behaviour now. Now instead mce_notify_user can be called directly
from interrupt (but not NMI) context.
The work queue only uses a single global work struct, which can be done safely
because it is always free to reuse before the trigger function is executed.
This way no events can be lost.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: low priority bug fix
This removes part of a a patch I added myself some time ago. After some
consideration the patch was a bad idea. In particular it stopped machine check
exceptions during code patching.
To quote the comment:
* MCEs only happen when something got corrupted and in this
* case we must do something about the corruption.
* Ignoring it is worse than a unlikely patching race.
* Also machine checks tend to be broadcast and if one CPU
* goes into machine check the others follow quickly, so we don't
* expect a machine check to cause undue problems during to code
* patching.
So undo the machine check related parts of
8f4e956b31 NMIs are still disabled.
This only removes code, the only additions are a new comment.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Bug fix
During suspend it is not reliable to process machine check
exceptions, because CPUs disappear but can still get machine check
broadcasts. Also the system is slightly more likely to
machine check them, but the handler is typically not a position
to handle them in a meaningfull way.
So disable them during suspend and enable them during resume.
Also make sure they are always disabled on hot-unplugged CPUs.
This new code assumes that suspend always hotunplugs all
non BP CPUs.
v2: Remove the WARN_ONs Thomas objected to.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: bug fix (with tolerant == 3)
do_exit cannot be called directly from the exception handler because
it can sleep and the exception handler runs on the exception stack.
Use force_sig() instead.
Based on a earlier patch by Ying Huang who debugged the problem.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Bug fix
This fixes a long standing bug in the machine check code. On resume the
boot CPU wouldn't get its vendor specific state like thermal handling
reinitialized. This means the boot cpu wouldn't ever get any thermal
events reported again.
Call the respective initialization functions on resume
v2: Remove ancient init because they don't have a resume device anyways.
Pointed out by Thomas Gleixner.
v3: Now fix the Subject too to reflect v2 change
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Mark the function local_allocate_threshold_blocks() with __cpuinit,
in order to remove the following section mismatch messages:
WARNING: arch/x86/kernel/cpu/mcheck/built-in.o(.text+0x1363): Section mismatch in reference from the function local_allocate_threshold_blocks() to the function .cpuinit.text:allocate_threshold_blocks()
The function local_allocate_threshold_blocks() references
the function __cpuinit allocate_threshold_blocks().
This is often because local_allocate_threshold_blocks lacks a __cpuinit
annotation or the annotation of allocate_threshold_blocks is wrong.
WARNING: arch/x86/kernel/cpu/built-in.o(.text+0x1def): Section mismatch in reference from the function local_allocate_threshold_blocks() to the function .cpuinit.text:allocate_threshold_blocks()
The function local_allocate_threshold_blocks() references
the function __cpuinit allocate_threshold_blocks().
This is often because local_allocate_threshold_blocks lacks a __cpuinit
annotation or the annotation of allocate_threshold_blocks is wrong.
WARNING: arch/x86/kernel/built-in.o(.text+0xef2b): Section mismatch in reference from the function local_allocate_threshold_blocks() to the function .cpuinit.text:allocate_threshold_blocks()
The function local_allocate_threshold_blocks() references
the function __cpuinit allocate_threshold_blocks().
This is often because local_allocate_threshold_blocks lacks a __cpuinit
annotation or the annotation of allocate_threshold_blocks is wrong.
All the callsites of this function are __cpuinit already, and all the
functions it calls are __cpuinit as well.
Signed-off-by: Leonardo Potenza <lpotenza@inwind.it>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (66 commits)
x86: export vector_used_by_percpu_irq
x86: use logical apicid in x2apic_cluster's x2apic_cpu_mask_to_apicid_and()
sched: nominate preferred wakeup cpu, fix
x86: fix lguest used_vectors breakage, -v2
x86: fix warning in arch/x86/kernel/io_apic.c
sched: fix warning in kernel/sched.c
sched: move test_sd_parent() to an SMP section of sched.h
sched: add SD_BALANCE_NEWIDLE at MC and CPU level for sched_mc>0
sched: activate active load balancing in new idle cpus
sched: bias task wakeups to preferred semi-idle packages
sched: nominate preferred wakeup cpu
sched: favour lower logical cpu number for sched_mc balance
sched: framework for sched_mc/smt_power_savings=N
sched: convert BALANCE_FOR_xx_POWER to inline functions
x86: use possible_cpus=NUM to extend the possible cpus allowed
x86: fix cpu_mask_to_apicid_and to include cpu_online_mask
x86: update io_apic.c to the new cpumask code
x86: Introduce topology_core_cpumask()/topology_thread_cpumask()
x86: xen: use smp_call_function_many()
x86: use work_on_cpu in x86/kernel/cpu/mcheck/mce_amd_64.c
...
Fixed up trivial conflict in kernel/time/tick-sched.c manually
Impact: Remove cpumask_t's from stack.
Simple transition to work_on_cpu(), rather than cpumask games.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Robert Richter <robert.richter@amd.com>
Cc: jacob.shin@amd.com
Impact: fix disabled MCE after resume
Don't prevent multiple initialization of MCEs.
Back from early prehistory mcheck_init() has a reentry check. Presumably
that was needed in very old kernels to prevent it entering twice.
But as Andreas points out this prevents CPU hotplug (and therefore resume)
to correctly reinitialize MCEs when a AP boots again after being
offlined.
Just drop the check.
Reported-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Update assorted email addresses and related info to point
to a single current, valid address.
additionally
- trivial CREDITS entry updates. (Not that this file means much any more)
- remove arjans dead redhat.com address from powernow driver
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
During CPU hot-remove the sysfs directory created by
threshold_create_bank(), defined in
arch/x86/kernel/cpu/mcheck/mce_amd_64.c, has to be removed before
its parent directory, created by mce_create_device(), defined in
arch/x86/kernel/cpu/mcheck/mce_64.c . Moreover, when the CPU in
question is hotplugged again, obviously the latter has to be created
before the former. At present, the right ordering is not enforced,
because all of these operations are carried out by CPU hotplug
notifiers which are not appropriately ordered with respect to each
other. This leads to serious problems on systems with two or more
multicore AMD CPUs, among other things during suspend and hibernation.
Fix the problem by placing threshold bank CPU hotplug callbacks in
mce_cpu_callback(), so that they are invoked at the right places,
if defined. Additionally, use kobject_del() to remove the sysfs
directory associated with the kobject created by
kobject_create_and_add() in threshold_create_bank(), to prevent the
kernel from crashing during CPU hotplug operations on systems with
two or more multicore AMD CPUs.
This patch fixes bug #11337.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Andi Kleen <andi@firstfloor.org>
Tested-by: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (31 commits)
NR_CPUS: Replace NR_CPUS in speedstep-centrino.c
cpumask: Provide a generic set of CPUMASK_ALLOC macros, FIXUP
NR_CPUS: Replace NR_CPUS in cpufreq userspace routines
NR_CPUS: Replace per_cpu(..., smp_processor_id()) with __get_cpu_var
NR_CPUS: Replace NR_CPUS in arch/x86/kernel/genapic_flat_64.c
NR_CPUS: Replace NR_CPUS in arch/x86/kernel/genx2apic_uv_x.c
NR_CPUS: Replace NR_CPUS in arch/x86/kernel/cpu/proc.c
NR_CPUS: Replace NR_CPUS in arch/x86/kernel/cpu/mcheck/mce_64.c
cpumask: Optimize cpumask_of_cpu in lib/smp_processor_id.c, fix
cpumask: Use optimized CPUMASK_ALLOC macros in the centrino_target
cpumask: Provide a generic set of CPUMASK_ALLOC macros
cpumask: Optimize cpumask_of_cpu in lib/smp_processor_id.c
cpumask: Optimize cpumask_of_cpu in kernel/time/tick-common.c
cpumask: Optimize cpumask_of_cpu in drivers/misc/sgi-xp/xpc_main.c
cpumask: Optimize cpumask_of_cpu in arch/x86/kernel/ldt.c
cpumask: Optimize cpumask_of_cpu in arch/x86/kernel/io_apic_64.c
cpumask: Replace cpumask_of_cpu with cpumask_of_cpu_ptr
Revert "cpumask: introduce new APIs"
cpumask: make for_each_cpu_mask a bit smaller
net: Pass reference to cpumask variable in net/sunrpc/svc.c
...
Fix up trivial conflicts in drivers/cpufreq/cpufreq.c manually
Use the new generic int attribute accessors for the x86 mce tolerant
attribute. Simple example to illustrate the new macros.
There are much more places all over the tree that could be converted
like this.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This allow to dynamically generate attributes and share show/store
functions between attributes. Right now most attributes are generated
by special macros and lots of duplicated code. With the attribute
passed it's instead possible to attach some data to the attribute
and then use that in shared low level functions to do different things.
I need this for the dynamically generated bank attributes in the x86
machine check code, but it'll allow some further cleanups.
I converted all users in tree to the new show/store prototype. It's a single
huge patch to avoid unbisectable sections.
Runtime tested: x86-32, x86-64
Compiled only: ia64, powerpc
Not compile tested/only grep converted: sh, arm, avr32
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* nr_cpu_ids should be used to allocate arrays based on the number of
cpu's present.
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use alternatives to select the workaround for the 11AP Pentium erratum
for the affected steppings on the fly rather than build time. Remove the
X86_GOOD_APIC configuration option and replace all the calls to
apic_write_around() with plain apic_write(), protecting accesses to the
ESR as appropriate due to the 3AP Pentium erratum. Remove
apic_read_around() and all its invocations altogether as not needed.
Remove apic_write_atomic() and all its implementing backends. The use of
ASM_OUTPUT2() is not strictly needed for input constraints, but I have
used it for readability's sake.
I had the feeling no one else was brave enough to do it, so I went ahead
and here it is. Verified by checking the generated assembly and tested
with both a 32-bit and a 64-bit configuration, also with the 11AP
"feature" forced on and verified with gdb on /proc/kcore to work as
expected (as an 11AP machines are quite hard to get hands on these days).
Some script complained about the use of "volatile", but apic_write() needs
it for the same reason and is effectively a replacement for writel(), so I
have disregarded it.
I am not sure what the policy wrt defconfig files is, they are generated
and there is risk of a conflict resulting from an unrelated change, so I
have left changes to them out. The option will get removed from them at
the next run.
Some testing with machines other than mine will be needed to avoid some
stupid mistake, but despite its volume, the change is not really that
intrusive, so I am fairly confident that because it works for me, it will
everywhere.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Quirks getting ignored was a bug. Below patch fixes the bug, until
we have the dynamic banks support.
Sysfs choice configuration should not have any issues with the earlier patch
as we look for NR_SYSFS_BANKS in do_machine_check().
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Max Asbock <masbock@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
attached is a no-brainer that makes kernel correctly report
NR_BANKS for MCE. We are right now limited to NR_BANKS==6, but the
error message will use the available number of banks instead of the
defined maximum.
For a Nehalem based system it will print:
"MCE: warning: using only 9 banks"
while the correct message would be
"MCE: warning: using only 6 banks"
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Change references from for_each_cpu_mask to for_each_cpu_mask_nr
where appropriate
Reviewed-by: Paul Jackson <pj@sgi.com>
Reviewed-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
commit 2d474871e2fb092eb46a0930aba5442e10eb96cc
Author: Mike Travis <travis@sgi.com>
Date: Mon May 12 21:21:13 2008 +0200
Eliminate the 6 bank restriction in 64 bit mce reporting code. This
restriction is artificial (due to static creation of sysfs files) and 32
bit code does not have any such restriction.
This change helps in reporting the details of machine checks on a
machine check exception with errors in bank 6 and above on CPUs that
support those banks. Without the patch, machine check errors in those
banks are not reported.
We still have 128 (MCE_EXTENDED_BANK) bank restriction instead of max
256 supported in hardware. That is not changed in the patch below as it
will have some user level mcelog utility dependency, with bank 128 being
used for thermal reporting currently.
The patch below does not create sysfs control (bankNctl) for banks
higher than 6 as well. That needs some pre-cleanup in /sysfs mce layout,
removal of per cpu /sysfs entries for bankctl as they are really global
system level control today. That change will follow. This basic change
is critical to report the detailed errors on banks higher than 6.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
At least on my Barcelona, I see MCE log entries after cold boot caused
by BIOS not properly clearing the respective registers. Therefore, this
patch extends the workaround to families 0x10 and 0x11 (the latter just
for completeness, I have nothing to verify this against).
At the same time, provide a way to make these entries visible via the
'mce=bootlog' command line option even on these machines.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
