Due to an erratum with certain AMD Athlon 64 processors, the
BIOS may need to force enable the LAHF_LM capability.
Unfortunately, in at least one case, the BIOS does this even
for processors that do not support the functionality.
Add a specific check that will clear the feature bit for
processors known not to support the LAHF/SAHF instructions.
Signed-off-by: Kevin Winchester <kjwinchester@gmail.com>
Acked-by: Borislav Petkov <petkovbb@googlemail.com>
LKML-Reference: <4A80A5AD.2000209@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Johannes Stezenbach reported that 'perf stat' does not count
cache-miss and cache-references events on his Pentium-M based
laptop.
This is because we left them blank in p6_perfmon_event_map[],
fill them in.
Reported-by: Johannes Stezenbach <js@sig21.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
My Latitude d630 seems to be handling thermal events in SMI by
lowering the max frequency of the CPU till it cools down but
still leaks the "everything is normal" events.
This spams the console and with high priority printks.
Adjust therm_throt driver to only print messages about the fact
that temperatire returned back to normal when leaving the
throttling state.
Also lower the severity of "back to normal" message from
KERN_CRIT to KERN_INFO.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Acked-by: H. Peter Anvin <hpa@zytor.com>
LKML-Reference: <20090810051513.0558F526EC9@mailhub.coreip.homeip.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If "fake panic" mode is turned on, just log panic message instead of
go real panic. This is used for testing only, so that the test suite
can check for the correct panic message and do regression testing for
MCE would go panic.
This patch is based on x86-tip.git/mce.
ChangeLog:
v5:
- Rebased on x86-tip.git/mce
v4:
- Move config file from sysfs to debugfs
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Because more debugfs files under mce dir will be create in mce.c.
ChangeLog:
v5:
- Rebased on x86-tip.git/mce
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Raise mode include raising as exception or raising as poll, it is
specified via the mce.inject_flags field.
This can be used to specify raise mode of UCNA, which is UC error but
raised not as exception. And this can be used to test the filter code
of poll handler or exception handler too. For example, enforce a poll
raise mode for a fatal MCE.
ChangeLog:
v2:
- Re-base on latest x86-tip.git/mce3
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
The cpu context is specified via the new mce.inject_flags fields.
This allows more realistic machine check testing in different
situations. "RANDOM" context is implemented via NMI broadcasting to
add randomization to testing.
AK: Fix NMI broadcasting check. Fix 32-bit building. Some race
fixes. Move to module. Various changes
ChangeLog:
v3:
- Re-based on latest x86-tip.git/mce4
- Fix 32-bit building
v2:
- Re-base on latest x86-tip.git/mce3
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Wei Chong Tan reported a fast-PIT-calibration corner-case:
| pit_expect_msb() is vulnerable to SMI disturbance corner case
| in some platforms which causes /proc/cpuinfo to show wrong
| CPU MHz value when quick_pit_calibrate() jumps to success
| section.
I think that the real issue isn't even an SMI - but the fact
that in the very last iteration of the loop, there's no
serializing instruction _after_ the last 'rdtsc'. So even in
the absense of SMI's, we do have a situation where the cycle
counter was read without proper serialization.
The last check should be done outside the outer loop, since
_inside_ the outer loop, we'll be testing that the PIT has
the right MSB value has the right value in the next iteration.
So only the _last_ iteration is special, because that's the one
that will not check the PIT MSB value any more, and because the
final 'get_cycles()' isn't serialized.
In other words:
- I'd like to move the PIT MSB check to after the last
iteration, rather than in every iteration
- I think we should comment on the fact that it's also a
serializing instruction and so 'fences in' the TSC read.
Here's a suggested replacement.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: "Tan, Wei Chong" <wei.chong.tan@intel.com>
Tested-by: "Tan, Wei Chong" <wei.chong.tan@intel.com>
LKML-Reference: <B28277FD4E0F9247A3D55704C440A140D5D683F3@pgsmsx504.gar.corp.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This moves flush_write_buffers() in
asm-generic/dma-mapping-common.h to
arch/x86/kernel/pci-nommu.c.
The purpose of this patch is that, we can avoid defining NULL
flush_write_buffers() on IA64 and SPARC.
dma-mapping-common.h is used by X86 and IA64 (and SPARC soon)
but only X86 with CONFIG_X86_OOSTORE or CONFIG_X86_PPRO_FENCE
actually uses flush_write_buffers(). CONFIG_X86_OOSTORE or
CONFIG_X86_PPRO_FENCE is usable with only kernel/pci-nommu.c
(that is, not usable with other X86 IOMMU implementations such
as SWIOTLB, VT-d, etc) so we can safely move
flush_write_buffers() in asm-generic/dma-mapping-common.h to
arch/x86/kernel/pci-nommu.c.
The further discussion is:
http://lkml.org/lkml/2009/6/28/104
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: davem@davemloft.net
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
LKML-Reference: <1249872797-1314-2-git-send-email-fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Implement a performance counter with:
attr.type = PERF_TYPE_HARDWARE
attr.config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS
attr.sample_period = 1
Using branch trace store (BTS) on x86 hardware, if available.
The from and to address for each branch can be sampled using:
PERF_SAMPLE_IP for the from address
PERF_SAMPLE_ADDR for the to address
[ v2: address review feedback, fix bugs ]
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
GDT_ENTRY_INIT is static initializer of desc_struct.
We already have similar macro GDT_ENTRY() but it's static
initializer for u64 and it cannot be used for desc_struct.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
LKML-Reference: <20090718151219.GD11294@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Though the most time we are to panic on irq-pin allocation
fails, for PCI interrupts it's not the case and we could
continue operate even if irq-pin allocation failed.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090805200931.GB5319@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The function graph tracer used to have a protection against NMI
while entering a function entry tracing. But this is useless now,
this tracer is reentrant and the ring buffer supports the NMI tracing.
We can then drop this protection.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
KVM would like to provide x2APIC interface to a guest without emulating
interrupt remapping device. The reason KVM prefers guest to use x2APIC
is that x2APIC interface is better virtualizable and provides better
performance than mmio xAPIC interface:
- msr exits are faster than mmio (no page table walk, emulation)
- no need to read back ICR to look at the busy bit
- one 64 bit ICR write instead of two 32 bit writes
- shared code with the Hyper-V paravirt interface
Included patch changes x2APIC enabling logic to enable it even if IR
initialization failed, but kernel runs under KVM and no apic id is
greater than 255 (if there is one spec requires BIOS to move to x2apic
mode before starting an OS).
-v2: fix build
-v3: fix bug causing compiler warning
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Sheng Yang <sheng@linux.intel.com>
Cc: "avi@redhat.com" <avi@redhat.com>
LKML-Reference: <20090720122417.GR5638@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
cpu_has_apic has already investigated boot_cpu_data
X86_FEATURE_APIC bit for being clear if condition is
triggered.
So there is no need to clear this bit second time.
Signed-off-by: Cyrill Gorcuno v <gorcunov@openvz.org>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
LKML-Reference: <20090722205259.GE15805@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
With CONFIG_STACK_PROTECTOR turned on, VMI doesn't boot with
more than one processor. The problem is with the gs value not
being initialized correctly when registering the secondary
processor for VMI's case.
The patch below initializes the gs value for the AP to
__KERNEL_STACK_CANARY. Without this the secondary processor
keeps on taking a GP on every gs access.
Signed-off-by: Alok N Kataria <akataria@vmware.com>
Cc: <stable@kernel.org> # for v2.6.30.x
LKML-Reference: <1249425262.18955.40.camel@ank32.eng.vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This makes the hardware passthrough mode work a lot more like the
software version, so that the behaviour of a kernel with 'iommu=pt'
is the same whether the hardware supports passthrough or not.
In particular:
- We use a single si_domain for the pass-through devices.
- 32-bit devices can be taken out of the pass-through domain so that
they don't have to use swiotlb.
- Devices will work again after being removed from a KVM guest.
- A potential oops on OOM (in init_context_pass_through()) is fixed.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
In uv_setup_irq(), the call to create_irq() initially assigns
IRQ vectors to cpu 0. The subsequent call to
assign_irq_vector() in arch_enable_uv_irq() migrates the IRQ to
another cpu and frees the cpu 0 vector - at least it will be
freed as soon as the "IRQ move" completes.
arch_enable_uv_irq() needs to send a cleanup IPI to complete
the IRQ move. Otherwise, assignment of GRU interrupts on large
systems (>200 cpus) will exhaust the cpu 0 interrupt vectors
and initialization of the GRU driver will fail.
Signed-off-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20090720142840.GA8885@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Change SGI UV default apicid mode to "physical". This is
required to match settings in the UV hub chip.
Signed-off-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20090727143856.GA8905@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The UV BIOS has added additional MMR ranges that are mapped via
EFI virtual mode mappings. These ranges should be deleted from
ranges mapped by uv_system_init().
Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: linux-mm@kvack.org
LKML-Reference: <20090727143656.GA7698@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
UV blades may not have any blade-local memory. Add a field
(nid) to the UV blade structure to indicates whether the node
has local memory. This is needed by the GRU driver (pushed
separately).
Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: linux-mm@kvack.org
LKML-Reference: <20090727143507.GA7006@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Older versions of binutils did not accept the naked "ASSERT" syntax;
it is considered an expression whose value needs to be assigned to
something.
Reported-tested-and-fixed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
The latest Apple MacBook (MacBook5,2) doesn't reboot successfully
under Linux; neither the EFI reboot method nor the default method
using the keyboard controller works (the system just hangs and doesn't
reset). However, the method using the "PCI reset register" at 0xcf9
does work.
This adds a quirk to detect this machine via DMI and force the
reboot_type to BOOT_CF9. With this it reboots successfully without
requiring a command-line option. Note that the EFI code forces
reboot_type to BOOT_EFI when the machine is booted via EFI, but this
overrides that since the core_initcall runs after the EFI
initialization code.
Signed-off-by: Paul Mackerras <paulus@samba.org>
LKML-Reference: <19062.56420.501516.316181@cargo.ozlabs.ibm.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
On x86_64, percpu variables current_task and kernel_stack are used for
get_current() and current_thread_info() respectively and thus are
often used close to each other. Move definition of current_task to
kernel/cpu/common.c right above kernel_stack definition and align it
to cacheline so that they always fall into the same cacheline. Two
percpu variables defined there together - irq_stack_ptr and irq_count
- are also pretty hot and will benefit from sharing the cacheline.
For consistency, current_task definition for x86_32 is also moved to
kernel/cpu/common.c.
Putting current_task and kernel_stack into the same cacheline was
suggested by Linus Torvalds.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
DECLARE/DEFINE_PER_CPU_PAGE_ALIGNED() put percpu variables in
.page_aligned section without adding any alignment restrictions.
Currently, this doesn't cause any problem because all users of the
macros have explicit page alignment and page-sized but it's much safer
to enforce page alignment from the macros. After all, it's what they
claim to do.
Add __aligned(PAGE_SIZE) to DECLARE/DEFINE_PER_CPU_PAGE_ALIGNED() and
drop explicit alignment from it users.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This avoids a "Malformed early option 'iommu'" warning on boot when
trying to use pass-through mode.
Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
As Andrew noted, my previous patch ("debug lockups: Improve lockup
detection") broke/removed SysRq-L support from architecture that do
not provide a __trigger_all_cpu_backtrace implementation.
Restore a fallback path and clean up the SysRq-L machinery a bit:
- Rename the arch method to arch_trigger_all_cpu_backtrace()
- Simplify the define
- Document the method a bit - in the hope of more architectures
adding support for it.
[ The patch touches Sparc code for the rename. ]
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "David S. Miller" <davem@davemloft.net>
LKML-Reference: <20090802140809.7ec4bb6b.akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When debugging a recent lockup bug i found various deficiencies
in how our current lockup detection helpers work:
- SysRq-L is not very efficient as it uses a workqueue, hence
it cannot punch through hard lockups and cannot see through
most soft lockups either.
- The SysRq-L code depends on the NMI watchdog - which is off
by default.
- We dont print backtraces from the RCU code's built-in
'RCU state machine is stuck' debug code. This debug
code tends to be one of the first (and only) mechanisms
that show that a lockup has occured.
This patch changes the code so taht we:
- Trigger the NMI backtrace code from SysRq-L instead of using
a workqueue (which cannot punch through hard lockups)
- Trigger print-all-CPU-backtraces from the RCU lockup detection
code
Also decouple the backtrace printing code from the NMI watchdog:
- Dont use variable size cpumasks (it might not be initialized
and they are a bit more fragile anyway)
- Trigger an NMI immediately via an IPI, instead of waiting
for the NMI tick to occur. This is a lot faster and can
produce more relevant backtraces. It will also work if the
NMI watchdog is disabled.
- Dont print the 'dazed and confused' message when we print
a backtrace from the NMI
- Do a show_regs() plus a dump_stack() to get maximum info
out of the dump. Worst-case we get two stacktraces - which
is not a big deal. Sometimes, if register content is
corrupted, the precise stack walker in show_regs() wont
give us a full backtrace - in this case dump_stack() will
do it.
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Early Pentium M models use different method for enabling TM2
(per paragraph 13.5.2.3 of the "Intel 64 and IA-32 Architectures
Software Developer's Manual Volume 3A: System Programming Guide,
Part 1").
Tested on the affected Pentium M variant (model == 13).
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
fseverities_coverage is never NULL in err_out code path.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Reviewed-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
mce_cap_init() and mce_cpu_quirks() can be tagged with __cpuinit.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Reviewed-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
