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Merge tag 'please-pull-fixmcelog' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras
Pull mcelog regression fix from Tony Luck:
"Fix regression - functions on the mce notifier chain should not be
able to decide that an event should not be logged"
* tag 'please-pull-fixmcelog' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
x86/mce: Fix regression. All error records should report via /dev/mcelog
Pull x86 perf updates from Ingo Molnar:
"This series tightens up RDPMC permissions: currently even highly
sandboxed x86 execution environments (such as seccomp) have permission
to execute RDPMC, which may leak various perf events / PMU state such
as timing information and other CPU execution details.
This 'all is allowed' RDPMC mode is still preserved as the
(non-default) /sys/devices/cpu/rdpmc=2 setting. The new default is
that RDPMC access is only allowed if a perf event is mmap-ed (which is
needed to correctly interpret RDPMC counter values in any case).
As a side effect of these changes CR4 handling is cleaned up in the
x86 code and a shadow copy of the CR4 value is added.
The extra CR4 manipulation adds ~ <50ns to the context switch cost
between rdpmc-capable and rdpmc-non-capable mms"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86: Add /sys/devices/cpu/rdpmc=2 to allow rdpmc for all tasks
perf/x86: Only allow rdpmc if a perf_event is mapped
perf: Pass the event to arch_perf_update_userpage()
perf: Add pmu callbacks to track event mapping and unmapping
x86: Add a comment clarifying LDT context switching
x86: Store a per-cpu shadow copy of CR4
x86: Clean up cr4 manipulation
I'm getting complaints from validation teams that have updated their
Linux kernels from ancient versions to current. They don't see the
error logs they expect. I tell the to unload any EDAC drivers[1], and
things start working again. The problem is that we short-circuit
the logging process if any function on the decoder chain claims to
have dealt with the problem:
ret = atomic_notifier_call_chain(&x86_mce_decoder_chain, 0, m);
if (ret == NOTIFY_STOP)
return;
The logic we used when we added this code was that we did not want
to confuse users with double reports of the same error.
But it turns out users are not confused - they are upset that they
don't see a log where their tools used to find a log.
I could also get into a long description of how the consumer of this
log does more than just decode model specific details of the error.
It keeps counts, tracks thresholds, takes actions and runs scripts
that can alert administrators to problems.
[1] We've recently compounded the problem because the acpi_extlog
driver also registers for this notifier and also returns NOTIFY_STOP.
Signed-off-by: Tony Luck <tony.luck@intel.com>
CR4 manipulation was split, seemingly at random, between direct
(write_cr4) and using a helper (set/clear_in_cr4). Unfortunately,
the set_in_cr4 and clear_in_cr4 helpers also poke at the boot code,
which only a small subset of users actually wanted.
This patch replaces all cr4 access in functions that don't leave cr4
exactly the way they found it with new helpers cr4_set_bits,
cr4_clear_bits, and cr4_set_bits_and_update_boot.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/495a10bdc9e67016b8fd3945700d46cfd5c12c2f.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We now switch to the kernel stack when a machine check interrupts
during user mode. This means that we can perform recovery actions
in the tail of do_machine_check()
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
We currently pretend that IST context is like standard exception
context, but this is incorrect. IST entries from userspace are like
standard exceptions except that they use per-cpu stacks, so they are
atomic. IST entries from kernel space are like NMIs from RCU's
perspective -- they are not quiescent states even if they
interrupted the kernel during a quiescent state.
Add and use ist_enter and ist_exit to track IST context. Even
though x86_32 has no IST stacks, we track these interrupts the same
way.
This fixes two issues:
- Scheduling from an IST interrupt handler will now warn. It would
previously appear to work as long as we got lucky and nothing
overwrote the stack frame. (I don't know of any bugs in this
that would trigger the warning, but it's good to be on the safe
side.)
- RCU handling in IST context was dangerous. As far as I know,
only machine checks were likely to trigger this, but it's good to
be on the safe side.
Note that the machine check handlers appears to have been missing
any context tracking at all before this patch.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Uncorrected no action required (UCNA) - is a uncorrected recoverable
machine check error that is not signaled via a machine check exception
and, instead, is reported to system software as a corrected machine
check error. UCNA errors indicate that some data in the system is
corrupted, but the data has not been consumed and the processor state
is valid and you may continue execution on this processor. UCNA errors
require no action from system software to continue execution. Note that
UCNA errors are supported by the processor only when IA32_MCG_CAP[24]
(MCG_SER_P) is set.
-- Intel SDM Volume 3B
Deferred errors are errors that cannot be corrected by hardware, but
do not cause an immediate interruption in program flow, loss of data
integrity, or corruption of processor state. These errors indicate
that data has been corrupted but not consumed. Hardware writes information
to the status and address registers in the corresponding bank that
identifies the source of the error if deferred errors are enabled for
logging. Deferred errors are not reported via machine check exceptions;
they can be seen by polling the MCi_STATUS registers.
-- AMD64 APM Volume 2
Above two items, both UCNA and Deferred errors belong to detected
errors, but they can't be corrected by hardware, and this is very
similar to Software Recoverable Action Optional (SRAO) errors.
Therefore, we can take some actions that have been used for handling
SRAO errors to handle UCNA and Deferred errors.
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Chen Yucong <slaoub@gmail.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Until now, the mce_severity mechanism can only identify the severity
of UCNA error as MCE_KEEP_SEVERITY. Meanwhile, it is not able to filter
out DEFERRED error for AMD platform.
This patch extends the mce_severity mechanism for handling
UCNA/DEFERRED error. In order to do this, the patch introduces a new
severity level - MCE_UCNA/DEFERRED_SEVERITY.
In addition, mce_severity is specific to machine check exception,
and it will check MCIP/EIPV/RIPV bits. In order to use mce_severity
mechanism in non-exception context, the patch also introduces a new
argument (is_excp) for mce_severity. `is_excp' is used to explicitly
specify the calling context of mce_severity.
Reviewed-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Signed-off-by: Chen Yucong <slaoub@gmail.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
There are some AMD CPU models which have thresholding banks but which
cannot generate a thresholding interrupt. This is denoted by the bit
MCi_MISC[IntP]. Make sure to check that bit before assigning the
thresholding interrupt handler.
Signed-off-by: Chen Yucong <slaoub@gmail.com>
[ Boris: save an indentation level and rewrite commit message. ]
Link: http://lkml.kernel.org/r/1412662128.28440.18.camel@debian
Signed-off-by: Borislav Petkov <bp@suse.de>
Aravind had the good question about why we're assigning a
software-defined bank when reporting error thresholding errors instead
of simply using the bank which reports the last error causing the
overflow.
Digging through git history, it pointed to
9526866439 ("[PATCH] x86_64: mce_amd support for family 0x10 processors")
which added that functionality. The problem with this, however, is that
tools don't know about software-defined banks and get puzzled. So drop
that K8_MCE_THRESHOLD_BASE and simply use the hw bank reporting the
thresholding interrupt.
Save us a couple of MSR reads while at it.
Reported-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@amd.com>
Link: https://lkml.kernel.org/r/5435B206.60402@amd.com
Signed-off-by: Borislav Petkov <bp@suse.de>
Assigning to mce_threshold_vector is loop-invariant code in
mce_amd_feature_init(). So do it only once, out of loop body.
Signed-off-by: Chen Yucong <slaoub@gmail.com>
Link: http://lkml.kernel.org/r/1412263212.8085.6.camel@debian
[ Boris: commit message corrections. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
mce_setup() does not gather the content of IA32_MCG_STATUS, so it
should be read explicitly. Moreover, we need to clear IA32_MCx_STATUS
to avoid that mce_log() logs the processed threshold event again
at next time.
But we do the logging ourselves and machine_check_poll() is completely
useless there. So kill it.
Signed-off-by: Chen Yucong <slaoub@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Avoid open coded calculations for bank MSRs by hiding the index
of higher bank MSRs in well-defined macros.
No semantic changes.
Signed-off-by: Chen Yucong <slaoub@gmail.com>
Link: http://lkml.kernel.org/r/1411438561-24319-1-git-send-email-slaoub@gmail.com
Signed-off-by: Borislav Petkov <bp@suse.de>
Pull percpu consistent-ops changes from Tejun Heo:
"Way back, before the current percpu allocator was implemented, static
and dynamic percpu memory areas were allocated and handled separately
and had their own accessors. The distinction has been gone for many
years now; however, the now duplicate two sets of accessors remained
with the pointer based ones - this_cpu_*() - evolving various other
operations over time. During the process, we also accumulated other
inconsistent operations.
This pull request contains Christoph's patches to clean up the
duplicate accessor situation. __get_cpu_var() uses are replaced with
with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().
Unfortunately, the former sometimes is tricky thanks to C being a bit
messy with the distinction between lvalues and pointers, which led to
a rather ugly solution for cpumask_var_t involving the introduction of
this_cpu_cpumask_var_ptr().
This converts most of the uses but not all. Christoph will follow up
with the remaining conversions in this merge window and hopefully
remove the obsolete accessors"
* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
irqchip: Properly fetch the per cpu offset
percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
Revert "powerpc: Replace __get_cpu_var uses"
percpu: Remove __this_cpu_ptr
clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
sparc: Replace __get_cpu_var uses
avr32: Replace __get_cpu_var with __this_cpu_write
blackfin: Replace __get_cpu_var uses
tile: Use this_cpu_ptr() for hardware counters
tile: Replace __get_cpu_var uses
powerpc: Replace __get_cpu_var uses
alpha: Replace __get_cpu_var
ia64: Replace __get_cpu_var uses
s390: cio driver &__get_cpu_var replacements
s390: Replace __get_cpu_var uses
mips: Replace __get_cpu_var uses
MIPS: Replace __get_cpu_var uses in FPU emulator.
arm: Replace __this_cpu_ptr with raw_cpu_ptr
...
intel_init_thermal() is called from a) at the time of system initializing
and b) at the time of system resume to initialize thermal
monitoring.
In case when thermal monitoring is handled by SMI, we get to know it via
printk(). Currently it gives the message at both cases, but its okay if
we get it only once and no need to get the same message at every time
system resumes.
So, limit showing this message only at system boot time by avoid showing
at system resume and reduce abusing kernel log buffer.
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/1411068135.5121.10.camel@localhost.localdomain
Signed-off-by: Ingo Molnar <mingo@kernel.org>
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x). This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.
Other use cases are for storing and retrieving data from the current
processors percpu area. __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.
__get_cpu_var() is defined as :
#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))
__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.
this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.
This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset. Thereby address calculations are avoided and less registers
are used when code is generated.
Transformations done to __get_cpu_var()
1. Determine the address of the percpu instance of the current processor.
DEFINE_PER_CPU(int, y);
int *x = &__get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(&y);
2. Same as #1 but this time an array structure is involved.
DEFINE_PER_CPU(int, y[20]);
int *x = __get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(y);
3. Retrieve the content of the current processors instance of a per cpu
variable.
DEFINE_PER_CPU(int, y);
int x = __get_cpu_var(y)
Converts to
int x = __this_cpu_read(y);
4. Retrieve the content of a percpu struct
DEFINE_PER_CPU(struct mystruct, y);
struct mystruct x = __get_cpu_var(y);
Converts to
memcpy(&x, this_cpu_ptr(&y), sizeof(x));
5. Assignment to a per cpu variable
DEFINE_PER_CPU(int, y)
__get_cpu_var(y) = x;
Converts to
__this_cpu_write(y, x);
6. Increment/Decrement etc of a per cpu variable
DEFINE_PER_CPU(int, y);
__get_cpu_var(y)++
Converts to
__this_cpu_inc(y)
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Commit ea431643d6 ("x86/mce: Fix CMCI preemption bugs") breaks RT by
the completely unrelated conversion of the cmci_discover_lock to a
regular (non raw) spinlock. This lock was annotated in commit
59d958d2c7 ("locking, x86: mce: Annotate cmci_discover_lock as raw")
with a proper explanation why.
The argument for converting the lock back to a regular spinlock was:
- it does percpu ops without disabling preemption. Preemption is not
disabled due to the mistaken use of a raw spinlock.
Which is complete nonsense. The raw_spinlock is disabling preemption in
the same way as a regular spinlock. In mainline spinlock maps to
raw_spinlock, in RT spinlock becomes a "sleeping" lock.
raw_spinlock has on RT exactly the same semantics as in mainline. And
because this lock is taken in non preemptible context it must be raw on
RT.
Undo the locking brainfart.
Reported-by: Clark Williams <williams@redhat.com>
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
BorisO reports that misc_register() fails often on xen. The current code
unregisters the CPU hotplug notifier in that case. If then a CPU is
offlined and onlined back again, we end up with a second timer running
on that CPU, leading to soft lockups and system hangs.
So let's leave the hotcpu notifier always registered - even if
mce_device_create failed for some cores and never unreg it so that we
can deal with the timer handling accordingly.
Reported-and-Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: http://lkml.kernel.org/r/1403274493-1371-1-git-send-email-boris.ostrovsky@oracle.com
Signed-off-by: Borislav Petkov <bp@suse.de>
There is very little and maybe practically nothing we can do to recover
from a system where at least one core has reached a timeout during the
whole monarch cores gathering. So panic when that happens.
Link: http://lkml.kernel.org/r/20140523091041.GA21332@pd.tnic
Signed-off-by: Borislav Petkov <bp@suse.de>
As requested by Linus add explicit __visible to the asmlinkage users.
This marks all functions visible to assembler.
Tree sweep for arch/x86/*
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1398984278-29319-3-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The following commit:
27f6c573e0 ("x86, CMCI: Add proper detection of end of CMCI storms")
Added two preemption bugs:
- machine_check_poll() does a get_cpu_var() without a matching
put_cpu_var(), which causes preemption imbalance and crashes upon
bootup.
- it does percpu ops without disabling preemption. Preemption is not
disabled due to the mistaken use of a raw spinlock.
To fix these bugs fix the imbalance and change
cmci_discover_lock to a regular spinlock.
Reported-by: Owen Kibel <qmewlo@gmail.com>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Chen, Gong <gong.chen@linux.intel.com>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexander Todorov <atodorov@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/n/tip-jtjptvgigpfkpvtQxpEk1at2@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
--
arch/x86/kernel/cpu/mcheck/mce.c | 4 +---
arch/x86/kernel/cpu/mcheck/mce_intel.c | 18 +++++++++---------
2 files changed, 10 insertions(+), 12 deletions(-)
Pull x86 fixes from Peter Anvin:
"This is a collection of minor fixes for x86, plus the IRET information
leak fix (forbid the use of 16-bit segments in 64-bit mode)"
NOTE! We may have to relax the "forbid the use of 16-bit segments in
64-bit mode" part, since there may be people who still run and depend on
16-bit Windows binaries under Wine.
But I'm taking this in the current unconditional form for now to see who
(if anybody) screams bloody murder. Maybe nobody cares. And maybe
we'll have to update it with some kind of runtime enablement (like our
vm.mmap_min_addr tunable that people who run dosemu/qemu/wine already
need to tweak).
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels
efi: Pass correct file handle to efi_file_{read,close}
x86/efi: Correct EFI boot stub use of code32_start
x86/efi: Fix boot failure with EFI stub
x86/platform/hyperv: Handle VMBUS driver being a module
x86/apic: Reinstate error IRQ Pentium erratum 3AP workaround
x86, CMCI: Add proper detection of end of CMCI storms
When CMCI storm persists for a long time(at least beyond predefined
threshold. It's 30 seconds for now), we can watch CMCI storm is
detected immediately after it subsides.
...
Dec 10 22:04:29 kernel: CMCI storm detected: switching to poll mode
Dec 10 22:04:59 kernel: CMCI storm subsided: switching to interrupt mode
Dec 10 22:04:59 kernel: CMCI storm detected: switching to poll mode
Dec 10 22:05:29 kernel: CMCI storm subsided: switching to interrupt mode
...
The problem is that our logic that determines that the storm has
ended is incorrect. We announce the end, re-enable interrupts and
realize that the storm is still going on, so we switch back to
polling mode. Rinse, repeat.
When a storm happens we disable signaling of errors via CMCI and begin
polling machine check banks instead. If we find any logged errors,
then we need to set a per-cpu flag so that our per-cpu tests that
check whether the storm is ongoing will see that errors are still
being logged independently of whether mce_notify_irq() says that the
error has been fully processed.
cmci_clear() is not the right tool to disable a bank. It disables the
interrupt for the bank as desired, but it also clears the bit for
this bank in "mce_banks_owned" so we will skip the bank when polling
(so we fail to see that the storm continues because we stop looking).
New cmci_storm_disable_banks() just disables the interrupt while
allowing polling to continue.
Reported-by: William Dauchy <wdauchy@gmail.com>
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
After fixing the CPU hotplug callback registration code, the callbacks
invoked for each online CPU, during the initialization phase in
thermal_throttle_init_device(), can no longer race with the actual CPU
hotplug notifier callbacks (in thermal_throttle_cpu_callback). Hence the
therm_cpu_lock is unnecessary now. Remove it.
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:
get_online_cpus();
for_each_online_cpu(cpu)
init_cpu(cpu);
register_cpu_notifier(&foobar_cpu_notifier);
put_online_cpus();
This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).
Instead, the correct and race-free way of performing the callback
registration is:
cpu_notifier_register_begin();
for_each_online_cpu(cpu)
init_cpu(cpu);
/* Note the use of the double underscored version of the API */
__register_cpu_notifier(&foobar_cpu_notifier);
cpu_notifier_register_done();
Fix the thermal throttle code in x86 by using this latter form of callback
registration.
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:
get_online_cpus();
for_each_online_cpu(cpu)
init_cpu(cpu);
register_cpu_notifier(&foobar_cpu_notifier);
put_online_cpus();
This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).
Instead, the correct and race-free way of performing the callback
registration is:
cpu_notifier_register_begin();
for_each_online_cpu(cpu)
init_cpu(cpu);
/* Note the use of the double underscored version of the API */
__register_cpu_notifier(&foobar_cpu_notifier);
cpu_notifier_register_done();
Fix the mce code in x86 by using this latter form of callback registration.
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull x86 RAS changes from Ingo Molnar:
- SCI reporting for other error types not only correctable ones
- GHES cleanups
- Add the functionality to override error reporting agents as some
machines are sporting a new extended error logging capability which,
if done properly in the BIOS, makes a corresponding EDAC module
redundant
- PCIe AER tracepoint severity levels fix
- Error path correction for the mce device init
- MCE timer fix
- Add more flexibility to the error injection (EINJ) debugfs interface
* 'x86-ras-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, mce: Fix mce_start_timer semantics
ACPI, APEI, GHES: Cleanup ghes memory error handling
ACPI, APEI: Cleanup alignment-aware accesses
ACPI, APEI, GHES: Do not report only correctable errors with SCI
ACPI, APEI, EINJ: Changes to the ACPI/APEI/EINJ debugfs interface
ACPI, eMCA: Combine eMCA/EDAC event reporting priority
EDAC, sb_edac: Modify H/W event reporting policy
EDAC: Add an edac_report parameter to EDAC
PCI, AER: Fix severity usage in aer trace event
x86, mce: Call put_device on device_register failure
So mce_start_timer() has a 'cpu' argument which is supposed to mean to
start a timer on that cpu. However, the code currently starts a timer on
the *current* cpu the function runs on and causes the sanity-check in
mce_timer_fn to fire:
WARNING: CPU: 0 PID: 0 at arch/x86/kernel/cpu/mcheck/mce.c:1286 mce_timer_fn
because it is running on the wrong cpu.
This was triggered by Prarit Bhargava <prarit@redhat.com> by offlining
all the cpus in succession.
Then, we were fiddling with the CMCI storm settings when starting the
timer whereas there's no need for that - if there's storm happening
on this newly restarted cpu, we're going to be in normal CMCI mode
initially and then when the CMCI interrupt starts firing, we're going to
go to the polling mode with the timer real soon.
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Reviewed-by: Chen, Gong <gong.chen@linux.intel.com>
Link: http://lkml.kernel.org/r/1387722156-5511-1-git-send-email-prarit@redhat.com
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>. Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
[ hpa: undid incorrect removal from arch/x86/kernel/head_32.S ]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Link: http://lkml.kernel.org/r/1389054026-12947-1-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Currently SCI is employed to handle corrected errors - memory corrected
errors, more specifically but in fact SCI still can be used to handle
any errors, e.g. uncorrected or even fatal ones if enabled by the BIOS.
Enable logging for those kinds of errors too.
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/1385363701-12387-1-git-send-email-gong.chen@linux.intel.com
[ Boris: massage commit message, rename function arg. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
This patch adds a call to put_device() when the device_register() call
has failed. This is required so that the last reference to the device is
given up.
Signed-off-by: Levente Kurusa <levex@linux.com>
Link: http://lkml.kernel.org/r/5298F900.9000208@linux.com
Signed-off-by: Borislav Petkov <bp@suse.de>
In latest UEFI spec(by now it is 2.4) memory error definition
for CPER (UEFI 2.4 Appendix N Common Platform Error Record)
adds some new fields. These fields help people to locate
memory error to an actual DIMM location.
Original-author: Tony Luck <tony.luck@intel.com>
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
an uncorrected error is reported. Ignore it when checking
error signatures.
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Merge tag 'please-pull-mce-f-bit' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras into x86/ras
Pull MCE-uncorrected-error fix from Tony Luck:
"Bit 12 may or may not be set in MCi_STATUS.MCACOD when
an uncorrected error is reported. Ignore it when checking
error signatures."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In commit 33d7885b59
x86/mce: Update MCE severity condition check
We simplified the rules to recognise each classification of recoverable
machine check combining the instruction and data fetch rules into a
single entry based on clarifications in the June 2013 SDM that all
recoverable events would be reported on the unaffected processor with
MCG_STATUS.EIPV=0 and MCG_STATUS.RIPV=1. Unfortunately the simplified
rule has a couple of bugs. Fix them here.
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.
After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.
Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings. In any case, they are temporary and harmless.
This removes all the arch/x86 uses of the __cpuinit macros from
all C files. x86 only had the one __CPUINIT used in assembly files,
and it wasn't paired off with a .previous or a __FINIT, so we can
delete it directly w/o any corresponding additional change there.
[1] https://lkml.org/lkml/2013/5/20/589
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Pull thermal management updates from Zhang Rui:
"There are not too many changes this time, except two new platform
thermal drivers, ti-soc-thermal driver and x86_pkg_temp_thermal
driver, and a couple of small fixes.
Highlights:
- move the ti-soc-thermal driver out of the staging tree to the
thermal tree.
- introduce the x86_pkg_temp_thermal driver. This driver registers
CPU digital temperature package level sensor as a thermal zone.
- small fixes/cleanups including removing redundant use of
platform_set_drvdata() and of_match_ptr for all platform thermal
drivers"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: (34 commits)
thermal: cpu_cooling: fix stub function
thermal: ti-soc-thermal: use standard GPIO DT bindings
thermal: MAINTAINERS: Add git tree path for SoC specific updates
thermal: fix x86_pkg_temp_thermal.c build and Kconfig
Thermal: Documentation for x86 package temperature thermal driver
Thermal: CPU Package temperature thermal
thermal: consider emul_temperature while computing trend
thermal: ti-soc-thermal: add DT example for DRA752 chip
thermal: ti-soc-thermal: add dra752 chip to device table
thermal: ti-soc-thermal: add thermal data for DRA752 chips
thermal: ti-soc-thermal: remove usage of IS_ERR_OR_NULL
thermal: ti-soc-thermal: freeze FSM while computing trend
thermal: ti-soc-thermal: remove external heat while extrapolating hotspot
thermal: ti-soc-thermal: update DT reference for OMAP5430
x86, mcheck, therm_throt: Process package thresholds
thermal: cpu_cooling: fix 'descend' check in get_property()
Thermal: spear: Remove redundant use of of_match_ptr
Thermal: kirkwood: Remove redundant use of of_match_ptr
Thermal: dove: Remove redundant use of of_match_ptr
Thermal: armada: Remove redundant use of of_match_ptr
...
The Corrected Machine Check structure (CMC) in HEST has a flag which can be
set by the firmware to indicate to the OS that it prefers to process the
corrected error events first. In this scenario, the OS is expected to not
monitor for corrected errors (through CMCI/polling). Instead, the firmware
notifies the OS on corrected error events through GHES.
Linux already has support for GHES. This patch adds support for parsing CMC
structure and to disable CMCI/polling if the firmware first flag is set.
Further, the list of machine check bank structures at the end of CMC is used
to determine which MCA banks function in FF mode, so that we continue to
monitor error events on the other banks.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
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Merge tag 'please-pull-mce-therm' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux
Pull thermal power-limit update from Tony Luck:
"Thermal limit warnings are too scary and cause unnecessary concern"
* tag 'please-pull-mce-therm' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
x86 thermal: Disable power limit notification interrupt by default
x86 thermal: Delete power-limit-notification console messages
Pull x86 tracing updates from Ingo Molnar:
"This tree adds IRQ vector tracepoints that are named after the handler
and which output the vector #, based on a zero-overhead approach that
relies on changing the IDT entries, by Seiji Aguchi.
The new tracepoints look like this:
# perf list | grep -i irq_vector
irq_vectors:local_timer_entry [Tracepoint event]
irq_vectors:local_timer_exit [Tracepoint event]
irq_vectors:reschedule_entry [Tracepoint event]
irq_vectors:reschedule_exit [Tracepoint event]
irq_vectors:spurious_apic_entry [Tracepoint event]
irq_vectors:spurious_apic_exit [Tracepoint event]
irq_vectors:error_apic_entry [Tracepoint event]
irq_vectors:error_apic_exit [Tracepoint event]
[...]"
* 'x86-tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tracing: Add config option checking to the definitions of mce handlers
trace,x86: Do not call local_irq_save() in load_current_idt()
trace,x86: Move creation of irq tracepoints from apic.c to irq.c
x86, trace: Add irq vector tracepoints
x86: Rename variables for debugging
x86, trace: Introduce entering/exiting_irq()
tracing: Add DEFINE_EVENT_FN() macro
the code for SRAR (software recoverable action required) errors.
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Merge tag 'please-pull-mce' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras into x86/ras
Pull MCE cleanup from Tony Luck:
"Changes to simplify the SDM means that we can also simplify
the code for SRAR (software recoverable action required) errors."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Update some SRAR severity conditions check to make it clearer,
according to latest Intel SDM Vol 3(June 2013), table 15-20.
Signed-off-by: Chen Gong <gong.chen@linux.intel.com>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Linus Torvalds