Allow user programs to write mce records into /dev/mcelog. When they do
that a fake machine check is triggered to test the machine check code.
This uses the MCE MSR wrappers added earlier.
The implementation is straight forward. There is a struct mce record
per CPU and the MCE MSR accesses get data from there if there is valid
data injected there. This allows to test the machine check code
relatively realistically because only the lowest layer of hardware
access is intercepted.
The test suite and injector are available at
git://git.kernel.org/pub/scm/utils/cpu/mce/mce-test.git
git://git.kernel.org/pub/scm/utils/cpu/mce/mce-inject.git
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
That's very easy using the infrastructure enabled earlier for MCE_INTEL
Untested.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Enable the 64bit MCE_INTEL code (CMCI, thermal interrupts) for 32bit NEW_MCE.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
The 64bit machine check code is in many ways much better than
the 32bit machine check code: it is more specification compliant,
is cleaner, only has a single code base versus one per CPU,
has better infrastructure for recovery, has a cleaner way to communicate
with user space etc. etc.
Use the 64bit code for 32bit too.
This is the second attempt to do this. There was one a couple of years
ago to unify this code for 32bit and 64bit. Back then this ran into some
trouble with K7s and was reverted.
I believe this time the K7 problems (and some others) are addressed.
I went over the old handlers and was very careful to retain
all quirks.
But of course this needs a lot of testing on old systems. On newer
64bit capable systems I don't expect much problems because they have been
already tested with the 64bit kernel.
I made this a CONFIG for now that still allows to select the old
machine check code. This is mostly to make testing easier,
if someone runs into a problem we can ask them to try
with the CONFIG switched.
The new code is default y for more coverage.
Once there is confidence the 64bit code works well on older hardware
too the CONFIG_X86_OLD_MCE and the associated code can be easily
removed.
This causes a behaviour change for 32bit installations. They now
have to install the mcelog package to be able to log
corrected machine checks.
The 64bit machine check code only handles CPUs which support the
standard Intel machine check architecture described in the IA32 SDM.
The 32bit code has special support for some older CPUs which
have non standard machine check architectures, in particular
WinChip C3 and Intel P5. I made those a separate CONFIG option
and kept them for now. The WinChip variant could be probably
removed without too much pain, it doesn't really do anything
interesting. P5 is also disabled by default (like it
was before) because many motherboards have it miswired, but
according to Alan Cox a few embedded setups use that one.
Forward ported/heavily changed version of old patch, original patch
included review/fixes from Thomas Gleixner, Bert Wesarg.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Xiaohui Xin and some other folks at Intel have been looking into what's
behind the performance hit of paravirt_ops when running native.
It appears that the hit is entirely due to the paravirtualized
spinlocks introduced by:
| commit 8efcbab674
| Date: Mon Jul 7 12:07:51 2008 -0700
|
| paravirt: introduce a "lock-byte" spinlock implementation
The extra call/return in the spinlock path is somehow
causing an increase in the cycles/instruction of somewhere around 2-7%
(seems to vary quite a lot from test to test). The working theory is
that the CPU's pipeline is getting upset about the
call->call->locked-op->return->return, and seems to be failing to
speculate (though I haven't seen anything definitive about the precise
reasons). This doesn't entirely make sense, because the performance
hit is also visible on unlock and other operations which don't involve
locked instructions. But spinlock operations clearly swamp all the
other pvops operations, even though I can't imagine that they're
nearly as common (there's only a .05% increase in instructions
executed).
If I disable just the pv-spinlock calls, my tests show that pvops is
identical to non-pvops performance on native (my measurements show that
it is actually about .1% faster, but Xiaohui shows a .05% slowdown).
Summary of results, averaging 10 runs of the "mmperf" test, using a
no-pvops build as baseline:
nopv Pv-nospin Pv-spin
CPU cycles 100.00% 99.89% 102.18%
instructions 100.00% 100.10% 100.15%
CPI 100.00% 99.79% 102.03%
cache ref 100.00% 100.84% 100.28%
cache miss 100.00% 90.47% 88.56%
cache miss rate 100.00% 89.72% 88.31%
branches 100.00% 99.93% 100.04%
branch miss 100.00% 103.66% 107.72%
branch miss rt 100.00% 103.73% 107.67%
wallclock 100.00% 99.90% 102.20%
The clear effect here is that the 2% increase in CPI is
directly reflected in the final wallclock time.
(The other interesting effect is that the more ops are
out of line calls via pvops, the lower the cache access
and miss rates. Not too surprising, but it suggests that
the non-pvops kernel is over-inlined. On the flipside,
the branch misses go up correspondingly...)
So, what's the fix?
Paravirt patching turns all the pvops calls into direct calls, so
_spin_lock etc do end up having direct calls. For example, the compiler
generated code for paravirtualized _spin_lock is:
<_spin_lock+0>: mov %gs:0xb4c8,%rax
<_spin_lock+9>: incl 0xffffffffffffe044(%rax)
<_spin_lock+15>: callq *0xffffffff805a5b30
<_spin_lock+22>: retq
The indirect call will get patched to:
<_spin_lock+0>: mov %gs:0xb4c8,%rax
<_spin_lock+9>: incl 0xffffffffffffe044(%rax)
<_spin_lock+15>: callq <__ticket_spin_lock>
<_spin_lock+20>: nop; nop /* or whatever 2-byte nop */
<_spin_lock+22>: retq
One possibility is to inline _spin_lock, etc, when building an
optimised kernel (ie, when there's no spinlock/preempt
instrumentation/debugging enabled). That will remove the outer
call/return pair, returning the instruction stream to a single
call/return, which will presumably execute the same as the non-pvops
case. The downsides arel 1) it will replicate the
preempt_disable/enable code at eack lock/unlock callsite; this code is
fairly small, but not nothing; and 2) the spinlock definitions are
already a very heavily tangled mass of #ifdefs and other preprocessor
magic, and making any changes will be non-trivial.
The other obvious answer is to disable pv-spinlocks. Making them a
separate config option is fairly easy, and it would be trivial to
enable them only when Xen is enabled (as the only non-default user).
But it doesn't really address the common case of a distro build which
is going to have Xen support enabled, and leaves the open question of
whether the native performance cost of pv-spinlocks is worth the
performance improvement on a loaded Xen system (10% saving of overall
system CPU when guests block rather than spin). Still it is a
reasonable short-term workaround.
[ Impact: fix pvops performance regression when running native ]
Analysed-by: "Xin Xiaohui" <xiaohui.xin@intel.com>
Analysed-by: "Li Xin" <xin.li@intel.com>
Analysed-by: "Nakajima Jun" <jun.nakajima@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Xen-devel <xen-devel@lists.xensource.com>
LKML-Reference: <4A0B62F7.5030802@goop.org>
[ fixed the help text ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove the EXPERIMENTAL tag from CONFIG_RELOCATABLE and make it the
default. Relocatable kernels have been used for a while now, and
should now have identical semantics to non-relocatable kernels when
loaded by a non-relocating bootloader.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Default CONFIG_PHYSICAL_START and CONFIG_PHYSICAL_ALIGN each to 16 MB,
so that both non-relocatable and relocatable kernels are loaded at
16 MB by a non-relocating bootloader. This is somewhat hacky, but it
appears to be the only way to do this that does not break some some
set of existing bootloaders.
We want to avoid the bottom 16 MB because of large page breakup,
memory holes, and ZONE_DMA. Embedded systems may need to reduce this,
or update their bootloaders to be aware of the new min_alignment field.
[ Impact: performance improvement, avoids problems on some systems ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
We only need to build relocations when we are building a 32-bit
relocatable kernel. Rather than unnecessarily complicating the
Makefiles, make an explicit Kbuild symbol for this.
[ Impact: permits future cleanup ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Conflicts:
arch/x86/kernel/apic/io_apic.c
Merge reason: non-trivial interaction between ongoing work in io_apic.c
and the NUMA migration feature in the irq tree.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
move_irq_desc() will try to move irq_desc to the home node if
the allocated one is not correct, in create_irq_nr().
( This can happen on devices that are on different nodes that
are using MSI, when drivers are loaded and unloaded randomly. )
v2: fix non-smp build
v3: add NUMA_IRQ_DESC to eliminate #ifdefs
[ Impact: improve irq descriptor locality on NUMA systems ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <49F95EAE.2050903@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The original feature of migrating irq_desc dynamic was too fragile
and was causing problems: it caused crashes on systems with lots of
cards with MSI-X when user-space irq-balancer was enabled.
We now have new patches that create irq_desc according to device
numa node. This patch removes the leftover bits of the dynamic balancer.
[ Impact: remove dead code ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <49F654AF.8000808@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Look at the:
diff -u arch/x86/boot/compressed/vmlinux_*.lds
output and realize that they're basially exactly the same except for
trivial naming differences, and the fact that the 64-bit version has a
"pgtable" thing.
So unify them.
There's some trivial cleanup there (make the output format a Kconfig thing
rather than doing #ifdef's for it, and unify both 32-bit and 64-bit BSS
end to "_ebss", where 32-bit used to use the traditional "_end"), but
other than that it's really very mindless and straigt conversion.
For example, I think we should aim to remove "startup_32" vs "startup_64",
and just call it "startup", and get rid of one more difference. I didn't
do that.
Also, notice the comment in the unified vmlinux.lds.S talks about
"head_64" and "startup_32" which is an odd and incorrect mix, but that was
actually what the old 64-bit only lds file had, so the confusion isn't
new, and now that mixing is arguably more accurate thanks to the
vmlinux.lds.S file being shared between the two cases ;)
[ Impact: cleanup, unification ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
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, hpet: Stop soliciting hpet=force users on ICH4M
x86: check boundary in setup_node_bootmem()
uv_time: add parameter to uv_read_rtc()
x86: hpet: fix periodic mode programming on AMD 81xx
x86: more than 8 32-bit CPUs requires X86_BIGSMP
x86: avoid theoretical spurious NMI backtraces with CONFIG_CPUMASK_OFFSTACK=y
x86: fix boot crash in NMI watchdog with CONFIG_CPUMASK_OFFSTACK=y and flat APIC
x86-64: fix FPU corruption with signals and preemption
x86/uv: fix for no memory at paddr 0
docs, x86: add nox2apic back to kernel-parameters.txt
x86: mm/numa_32.c calculate_numa_remap_pages should use __init
x86, kbuild: make "make install" not depend on vmlinux
x86/uv: fix init of cpu-less nodes
x86/uv: fix init of memory-less nodes
* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86/irq: mark NUMA_MIGRATE_IRQ_DESC broken
x86, irq: Remove IRQ_DISABLED check in process context IRQ move
$ cat x86-more-than-8-cpus-requires-bigsmp.patch
Enforce NR_CPUS <= 8 limitation if X86_BIGSMP not set
Configuring more than 8 logical CPUs on 32-bit x86 requires
X86_BIGSMP to be set in order to boot successfully, if more than 8
logical CPUs are actually found at boot time. The X86_BIGSMP help
text describes that it is required to be set if more than 8 CPUs
are configured, but this was previously not enforced.
This configuration error has affected multiple distributions:
https://bugzilla.redhat.com/show_bug.cgi?id=480844https://issues.rpath.com/browse/RPL-3022
Signed-off-by: Michael K Johnson <johnsonm@rpath.com>
LKML-Reference: <20090422014448.GB32541@logo.rdu.rpath.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
It causes crash on system with lots of cards with MSI-X
when irq_balancer enabled...
The patches fixing it were both complex and fragile, according
to Eric they were also doing quite dangerous things to the
hardware.
Instead we now have patches that solve this problem via static
NUMA node mappings - not dynamic allocation and balancing.
The patches are much simpler than this method but are still too
large outside of the merge window, so we mark the dynamic balancer
as broken for now, and queue up the new approach for v2.6.31.
[ Impact: deactivate broken kernel feature ]
Reported-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <49E68C41.4020801@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86/uv' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: UV BAU distribution and payload MMRs
x86: UV: BAU partition-relative distribution map
x86, uv: add Kconfig dependency on NUMA for UV systems
x86: prevent /sys/firmware/sgi_uv from being created on non-uv systems
x86, UV: Fix for nodes with memory and no cpus
x86, UV: system table in bios accessed after unmap
x86: UV BAU messaging timeouts
x86: UV BAU and nodes with no memory
Impact: build fix
Add Kconfig dependency on NUMA for enabling UV. Although it might
be possible to configure non-NUMA UV systems, they are unsupported
and not interesting. Much of the infrastructure for UV requires
NUMA support.
Signed-off-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20090403203942.GA20137@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This build failure:
| drivers/pci/dmar.c:47: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘dmar_tbl_size’
| drivers/pci/dmar.c:62: warning: ‘struct acpi_dmar_device_scope’ declared inside parameter list
| drivers/pci/dmar.c:62: warning: its scope is only this definition or declaration, which is probably not what you want
Triggers due to this commit:
d0b03bd: x2apic/intr-remap: decouple interrupt remapping from x2apic
Which exposed a pre-existing but dormant fragility of the 'select X86_X2APIC'
it moved around and turned that fragility into a build failure.
Replace it with a proper 'depends on' construct.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
LKML-Reference: <1239084280.22733.404.camel@macbook.infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge reason: we have gathered quite a few conflicts, need to merge upstream
Conflicts:
arch/powerpc/kernel/Makefile
arch/x86/ia32/ia32entry.S
arch/x86/include/asm/hardirq.h
arch/x86/include/asm/unistd_32.h
arch/x86/include/asm/unistd_64.h
arch/x86/kernel/cpu/common.c
arch/x86/kernel/irq.c
arch/x86/kernel/syscall_table_32.S
arch/x86/mm/iomap_32.c
include/linux/sched.h
kernel/Makefile
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (413 commits)
tracing, net: fix net tree and tracing tree merge interaction
tracing, powerpc: fix powerpc tree and tracing tree interaction
ring-buffer: do not remove reader page from list on ring buffer free
function-graph: allow unregistering twice
trace: make argument 'mem' of trace_seq_putmem() const
tracing: add missing 'extern' keywords to trace_output.h
tracing: provide trace_seq_reserve()
blktrace: print out BLK_TN_MESSAGE properly
blktrace: extract duplidate code
blktrace: fix memory leak when freeing struct blk_io_trace
blktrace: fix blk_probes_ref chaos
blktrace: make classic output more classic
blktrace: fix off-by-one bug
blktrace: fix the original blktrace
blktrace: fix a race when creating blk_tree_root in debugfs
blktrace: fix timestamp in binary output
tracing, Text Edit Lock: cleanup
tracing: filter fix for TRACE_EVENT_FORMAT events
ftrace: Using FTRACE_WARN_ON() to check "freed record" in ftrace_release()
x86: kretprobe-booster interrupt emulation code fix
...
Fix up trivial conflicts in
arch/parisc/include/asm/ftrace.h
include/linux/memory.h
kernel/extable.c
kernel/module.c
interrupt remapping must be enabled before enabling x2apic, but
interrupt remapping doesn't depend on x2apic, it can be used
separately. Enable interrupt remapping in init_dmars even x2apic
is not supported.
[dwmw2: Update Kconfig accordingly, fix build with INTR_REMAP && !X2APIC]
Signed-off-by: Weidong Han <weidong.han@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (28 commits)
trivial: Update my email address
trivial: NULL noise: drivers/mtd/tests/mtd_*test.c
trivial: NULL noise: drivers/media/dvb/frontends/drx397xD_fw.h
trivial: Fix misspelling of "Celsius".
trivial: remove unused variable 'path' in alloc_file()
trivial: fix a pdlfush -> pdflush typo in comment
trivial: jbd header comment typo fix for JBD_PARANOID_IOFAIL
trivial: wusb: Storage class should be before const qualifier
trivial: drivers/char/bsr.c: Storage class should be before const qualifier
trivial: h8300: Storage class should be before const qualifier
trivial: fix where cgroup documentation is not correctly referred to
trivial: Give the right path in Documentation example
trivial: MTD: remove EOL from MODULE_DESCRIPTION
trivial: Fix typo in bio_split()'s documentation
trivial: PWM: fix of #endif comment
trivial: fix typos/grammar errors in Kconfig texts
trivial: Fix misspelling of firmware
trivial: cgroups: documentation typo and spelling corrections
trivial: Update contact info for Jochen Hein
trivial: fix typo "resgister" -> "register"
...
* git://git.infradead.org/iommu-2.6:
intel-iommu: Fix address wrap on 32-bit kernel.
intel-iommu: Enable DMAR on 32-bit kernel.
intel-iommu: fix PCI device detach from virtual machine
intel-iommu: VT-d page table to support snooping control bit
iommu: Add domain_has_cap iommu_ops
intel-iommu: Snooping control support
Fixed trivial conflicts in arch/x86/Kconfig and drivers/pci/intel-iommu.c
CONFIG_DEBUG_PAGEALLOC is now supported by x86, powerpc, sparc64, and
s390. This patch implements it for the rest of the architectures by
filling the pages with poison byte patterns after free_pages() and
verifying the poison patterns before alloc_pages().
This generic one cannot detect invalid page accesses immediately but
invalid read access may cause invalid dereference by poisoned memory and
invalid write access can be detected after a long delay.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (60 commits)
dma-debug: make memory range checks more consistent
dma-debug: warn of unmapping an invalid dma address
dma-debug: fix dma_debug_add_bus() definition for !CONFIG_DMA_API_DEBUG
dma-debug/x86: register pci bus for dma-debug leak detection
dma-debug: add a check dma memory leaks
dma-debug: add checks for kernel text and rodata
dma-debug: print stacktrace of mapping path on unmap error
dma-debug: Documentation update
dma-debug: x86 architecture bindings
dma-debug: add function to dump dma mappings
dma-debug: add checks for sync_single_sg_*
dma-debug: add checks for sync_single_range_*
dma-debug: add checks for sync_single_*
dma-debug: add checking for [alloc|free]_coherent
dma-debug: add add checking for map/unmap_sg
dma-debug: add checking for map/unmap_page/single
dma-debug: add core checking functions
dma-debug: add debugfs interface
dma-debug: add kernel command line parameters
dma-debug: add initialization code
...
Fix trivial conflicts due to whitespace changes in arch/x86/kernel/pci-nommu.c
Impact: disable unused code
x86 is fully converted to flow handlers. No need to keep the
deprecated __do_IRQ() support active.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If we fix a few highmem-related thinkos and a couple of printk format
warnings, the Intel IOMMU driver works fine in a 32-bit kernel.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Impact: disable unused code
x86 is fully converted to flow handlers. No need to keep the
deprecated __do_IRQ() support active.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Provide the x86 trace callbacks to trace syscalls.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
LKML-Reference: <1236401580-5758-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: configuration bug fix
Just like for x86-64, the range of widths valid for NODE_SHIFT is not
unbounded. The upper bound 64-bit uses is definitely also an upper
bound for 32-bit.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <49B90F12.76E4.0078.0@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: New major feature
This patch add kexec jump support for x86_64. More information about
kexec jump can be found in corresponding x86_32 support patch.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Introduce:
cat /sys/kernel/debug/x86/cpu/*
for Intel and AMD processors to view / debug the state of each CPU.
By using this we can debug whole range of registers and other
cpu information for debugging purpose and monitor how things
are changing.
This can be useful for developers as well as for users.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
LKML-Reference: <1236701373.3387.4.camel@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Now that the obvious bugs have been worked out, specifically
the iwlagn issue, and the write buffer errata, DMAR should be safe
to turn back on by default. (We've had it on since those patches were
first written a few weeks ago, without any noticeable bug reports
(most have been due to the dma-api debug patchset.))
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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: cleaner and consistent bootmem wrapping
By setting CONFIG_HAVE_ARCH_BOOTMEM_NODE, archs can define
arch-specific wrappers for bootmem allocation. However, this is done
a bit strangely in that only the high level convenience macros can be
changed while lower level, but still exported, interface functions
can't be wrapped. This not only is messy but also leads to strange
situation where alloc_bootmem() does what the arch wants it to do but
the equivalent __alloc_bootmem() call doesn't although they should be
able to be used interchangeably.
This patch updates bootmem such that archs can override / wrap the
backend function - alloc_bootmem_core() instead of the highlevel
interface functions to allow simpler and consistent wrapping. Also,
HAVE_ARCH_BOOTMEM_NODE is renamed to HAVE_ARCH_BOOTMEM.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@saeurebad.de>
Impact: remove unused/broken code
The Voyager subarch last built successfully on the v2.6.26 kernel
and has been stale since then and does not build on the v2.6.27,
v2.6.28 and v2.6.29-rc5 kernels.
No actual users beyond the maintainer reported this breakage.
Patches were sent and most of the fixes were accepted but the
discussion around how to do a few remaining issues cleanly
fizzled out with no resolution and the code remained broken.
In the v2.6.30 x86 tree development cycle 32-bit subarch support
has been reworked and removed - and the Voyager code, beyond the
build problems already known, needs serious and significant
changes and probably a rewrite to support it.
CONFIG_X86_VOYAGER has been marked BROKEN then. The maintainer has
been notified but no patches have been sent so far to fix it.
While all other subarchs have been converted to the new scheme,
voyager is still broken. We'd prefer to receive patches which
clean up the current situation in a constructive way, but even in
case of removal there is no obstacle to add that support back
after the issues have been sorted out in a mutually acceptable
fashion.
So remove this inactive code for now.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Change the CONFIG_X86_EXTENDED_PLATFORM help text to display the
32bit/64bit extended platform list. This is as suggested by Ingo.
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: shai@scalex86.org
Cc: "Benzi Galili (Benzi@ScaleMP.com)" <benzi@scalemp.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: use new dynamic allocator, unified access to static/dynamic
percpu memory
Convert to the new dynamic percpu allocator.
* implement populate_extra_pte() for both 32 and 64
* update setup_per_cpu_areas() to use pcpu_setup_static()
* define __addr_to_pcpu_ptr() and __pcpu_ptr_to_addr()
* define config HAVE_DYNAMIC_PER_CPU_AREA
Signed-off-by: Tejun Heo <tj@kernel.org>
- make oprofile build
- select X86_X2APIC from X86_UV - it relies on it
- export genapic for oprofile modular build
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
so could deselect x2apic
and INTR_REMAP will select x2apic
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit:
aced3ce: x86/Voyager: remove HIBERNATION Kconfig quirk
Made hibernation only available on UP - instead of making it available
on all of x86. Fix it.
Reported-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Patch to rename the CONFIG_X86_NON_STANDARD to CONFIG_X86_EXTENDED_PLATFORM.
The new name represents the subarches better. Also, default this to 'y'
so that many of the sub architectures that were not easily visible now
become visible.
Also re-organize the extended architecture platform and non standard
platform list alphabetically as suggested by Ingo.
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: stack protector for x86_32
Implement stack protector for x86_32. GDT entry 28 is used for it.
It's set to point to stack_canary-20 and have the length of 24 bytes.
CONFIG_CC_STACKPROTECTOR turns off CONFIG_X86_32_LAZY_GS and sets %gs
to the stack canary segment on entry. As %gs is otherwise unused by
the kernel, the canary can be anywhere. It's defined as a percpu
variable.
x86_32 exception handlers take register frame on stack directly as
struct pt_regs. With -fstack-protector turned on, gcc copies the
whole structure after the stack canary and (of course) doesn't copy
back on return thus losing all changed. For now, -fno-stack-protector
is added to all files which contain those functions. We definitely
need something better.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: pt_regs changed, lazy gs handling made optional, add slight
overhead to SAVE_ALL, simplifies error_code path a bit
On x86_32, %gs hasn't been used by kernel and handled lazily. pt_regs
doesn't have place for it and gs is saved/loaded only when necessary.
In preparation for stack protector support, this patch makes lazy %gs
handling optional by doing the followings.
* Add CONFIG_X86_32_LAZY_GS and place for gs in pt_regs.
* Save and restore %gs along with other registers in entry_32.S unless
LAZY_GS. Note that this unfortunately adds "pushl $0" on SAVE_ALL
even when LAZY_GS. However, it adds no overhead to common exit path
and simplifies entry path with error code.
* Define different user_gs accessors depending on LAZY_GS and add
lazy_save_gs() and lazy_load_gs() which are noop if !LAZY_GS. The
lazy_*_gs() ops are used to save, load and clear %gs lazily.
* Define ELF_CORE_COPY_KERNEL_REGS() which always read %gs directly.
xen and lguest changes need to be verified.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The function graph tracer piggy backed onto the dynamic ftracer
to use the in_nmi custom code for dynamic tracing. The problem
was (as Andrew Morton pointed out) it really only wanted to bail
out if the context of the current CPU was in NMI context. But the
dynamic ftrace in_nmi custom code was true if _any_ CPU happened
to be in NMI context.
Now that we have a generic in_nmi interface, this patch changes
the function graph code to use it instead of the dynamic ftarce
custom code.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: prevent deadlock in NMI
The ring buffers are not yet totally lockless with writing to
the buffer. When a writer crosses a page, it grabs a per cpu spinlock
to protect against a reader. The spinlocks taken by a writer are not
to protect against other writers, since a writer can only write to
its own per cpu buffer. The spinlocks protect against readers that
can touch any cpu buffer. The writers are made to be reentrant
with the spinlocks disabling interrupts.
The problem arises when an NMI writes to the buffer, and that write
crosses a page boundary. If it grabs a spinlock, it can be racing
with another writer (since disabling interrupts does not protect
against NMIs) or with a reader on the same CPU. Luckily, most of the
users are not reentrant and protects against this issue. But if a
user of the ring buffer becomes reentrant (which is what the ring
buffers do allow), if the NMI also writes to the ring buffer then
we risk the chance of a deadlock.
This patch moves the ftrace_nmi_enter called by nmi_enter() to the
ring buffer code. It replaces the current ftrace_nmi_enter that is
used by arch specific code to arch_ftrace_nmi_enter and updates
the Kconfig to handle it.
When an NMI is called, it will set a per cpu variable in the ring buffer
code and will clear it when the NMI exits. If a write to the ring buffer
crosses page boundaries inside an NMI, a trylock is used on the spin
lock instead. If the spinlock fails to be acquired, then the entry
is discarded.
This bug appeared in the ftrace work in the RT tree, where event tracing
is reentrant. This workaround solved the deadlocks that appeared there.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
- Consistent alignment of help text
- Use the ---help--- keyword everywhere consistently as a visual separator
- fix whitespace mismatches
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Due to recurring issues with DMAR support on certain platforms.
There's a number of filesystem corruption incidents reported:
https://bugzilla.redhat.com/show_bug.cgi?id=479996http://bugzilla.kernel.org/show_bug.cgi?id=12578
Provide a Kconfig option to change whether it is enabled by
default.
If disabled, it can still be reenabled by passing intel_iommu=on to the
kernel. Keep the .config option off by default.
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-By: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
just like 64 bit switch from flat logical APIC messages to
flat physical mode automatically.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
X86_PC is the only remaining 'sub' architecture, so we dont need
it anymore.
This also cleans up a few spurious references to X86_PC in the
driver space - those certainly should be X86.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
X86_GENERICARCH is a misnomer - it contains non-PC 32-bit architectures
that are not included in the default build.
Rename it to X86_32_NON_STANDARD.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Move X86_VSMP out of the subarch menu - this way it can be enabled
together with standard PC support as well, in the same kernel.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
- make X86_GENERICARCH depend X86_NON_STANDARD
- move X86_SUMMIT, X86_ES7000 and X86_BIGSMP out of the subarchitecture
menu and under this option
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Move X86_ELAN (old, NCR hw platform built on Intel CPUs) from the
subarchitecture menu to the non-standard-platform section.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Move X86_ELAN (old, AMD based web-boxes) from the subarchitecture
menu to the non-standard-platform section.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Voyager has this ISA quirk (because Voyager has no ISA support):
config ISA
bool "ISA support"
depends on !X86_VOYAGER
There's a ton of x86 hardware that does not support ISA, and because
most ISA drivers cannot auto-detect in a safe way, the convention in
the kernel has always been to not enable ISA drivers if they are not
needed.
Voyager users can do likewise - no need for a Kconfig quirk.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Voyager has this PM/ACPI Kconfig quirk:
menu "Power management and ACPI options"
depends on !X86_VOYAGER
Most of the PM features are auto-detect so they should be safe to run
on just about any hardware. (If not, those instances need fixing.)
In any case, if a kernel is built for Voyager, the power management
options can be disabled.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Voyager has this Kconfig quirk:
config HOTPLUG_CPU
bool "Support for hot-pluggable CPUs"
depends on SMP && HOTPLUG && !X86_VOYAGER
But this exception will be moot once Voyager starts using the
generic x86 code.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If no MCE code is desired on Voyager hw then the solution
is to turn them off in the .config - and to extend the MCE
code to not initialize on Voyager.
Remove the build-time quirk.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The lapic/ioapic code properly auto-detects and is safe to run on CPUs that
have no local APIC. (or which have their lapic turned off in the hardware)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove this Kconfig quirk:
config PARAVIRT
bool "Enable paravirtualization code"
depends on !X86_VOYAGER
help
Voyager support built into a kernel does not preclude paravirt support.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Voyager has this quirk currently:
config KVM_GUEST
bool "KVM Guest support"
select PARAVIRT
depends on !X86_VOYAGER
Voyager support built into a kernel image does not exclude
KVM paravirt guest support - so remove this quirk.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Voyager has this build-time quirk to exclude KVM_CLOCK:
bool "KVM paravirtualized clock"
select PARAVIRT
select PARAVIRT_CLOCK
depends on !X86_VOYAGER
Voyager support built into a kernel image does not exclude
KVM paravirt clock support - so remove this quirk.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
x86/Voyager has this build-time quirk:
bool "VMI Guest support"
select PARAVIRT
depends on X86_32
depends on !X86_VOYAGER
Since VMI is auto-detected (and Voyager will be auto-detected) there's no
reason for this quirk.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
