x86/smp: Drop 32-bit "bigsmp" machine support

The x86-32 kernel used to support multiple platforms with more than eight
logical CPUs, from the 1999-2003 timeframe: Sequent NUMA-Q, IBM Summit,
Unisys

x86/smp: Drop 32-bit "bigsmp" machine support

The x86-32 kernel used to support multiple platforms with more than eight
logical CPUs, from the 1999-2003 timeframe: Sequent NUMA-Q, IBM Summit,
Unisys ES7000 and HP F8. Support for all except the latter was dropped
back in 2014, leaving only the F8 based DL740 and DL760 G2 machines in
this catery, with up to eight single-core Socket-603 Xeon-MP processors
with hyperthreading.

Like the already removed machines, the HP F8 servers at the time cost
upwards of $100k in typical configurations, but were quickly obsoleted
by their 64-bit Socket-604 cousins and the AMD Opteron.

Earlier servers with up to 8 Pentium Pro or Xeon processors remain
fully supported as they had no hyperthreading. Similarly, the more
common 4-socket Xeon-MP machines with hyperthreading using Intel
or ServerWorks chipsets continue to work without this, and all the
multi-core Xeon processors also run 64-bit kernels.

While the "bigsmp" support can also be used to run on later 64-bit
machines (including VM guests), it seems best to discourage that
and get any remaining users to update their kernels to 64-bit builds
on these. As a side-effect of this, there is also no more need to
support NUMA configurations on 32-bit x86, as all true 32-bit
NUMA platforms are already gone.

Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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arch/x86: Fix typos

Fix typos, most reported by "codespell arch/x86". Only touches comments,
no code changes.

Signed-off-by: Bjorn Helgaas <[email protected]>
Signed-off-by: Ingo Molnar <mingo@k

arch/x86: Fix typos

Fix typos, most reported by "codespell arch/x86". Only touches comments,
no code changes.

Signed-off-by: Bjorn Helgaas <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Reviewed-by: Randy Dunlap <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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x86/apic: Provide common init infrastructure

In preparation for converting the hotpath APIC callbacks to static keys,
provide common initialization infrastructure.

Lift apic_install_drivers() from

x86/apic: Provide common init infrastructure

In preparation for converting the hotpath APIC callbacks to static keys,
provide common initialization infrastructure.

Lift apic_install_drivers() from probe_64.c and convert all places which
switch the apic instance by storing the pointer to use apic_install_driver()
as a first step.

Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Dave Hansen <[email protected]>
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Tested-by: Michael Kelley <[email protected]>
Tested-by: Sohil Mehta <[email protected]>
Tested-by: Juergen Gross <[email protected]> # Xen PV (dom0 and unpriv. guest)

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x86/PCI: Remove unused HyperTransport interrupt support

There are no in-tree callers of ht_create_irq(), the driver interface for
HyperTransport interrupts, left. Remove the unused entry point and

x86/PCI: Remove unused HyperTransport interrupt support

There are no in-tree callers of ht_create_irq(), the driver interface for
HyperTransport interrupts, left. Remove the unused entry point and all the
supporting code.

See 8b955b0dddb3 ("[PATCH] Initial generic hypertransport interrupt
support").

Signed-off-by: Bjorn Helgaas <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: "Eric W. Biederman" <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: [email protected]
Cc: Benjamin Herrenschmidt <[email protected]>
Link: https://lkml.kernel.org/r/20171122221337.3877.23362.stgit@bhelgaas-glaptop.roam.corp.google.com

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <[email protected]>
Reviewed-by: Philippe Ombredanne <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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x86/apic: Sanitize 32/64bit APIC callbacks

The 32bit and the 64bit implementation of default_cpu_present_to_apicid()
and default_check_phys_apicid_present() are exactly the same, but
implemented and

x86/apic: Sanitize 32/64bit APIC callbacks

The 32bit and the 64bit implementation of default_cpu_present_to_apicid()
and default_check_phys_apicid_present() are exactly the same, but
implemented and located differently.

Move them to common apic code and get rid of the pointless difference.

Signed-off-by: Thomas Gleixner <[email protected]>
Tested-by: Juergen Gross <[email protected]>
Tested-by: Yu Chen <[email protected]>
Acked-by: Juergen Gross <[email protected]>
Cc: Boris Ostrovsky <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Marc Zyngier <[email protected]>
Cc: Alok Kataria <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Rui Zhang <[email protected]>
Cc: "K. Y. Srinivasan" <[email protected]>
Cc: Arjan van de Ven <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Len Brown <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

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kernel: add kcov code coverage

kcov provides code coverage collection for coverage-guided fuzzing
(randomized testing). Coverage-guided fuzzing is a testing technique
that uses coverage feedback to

kernel: add kcov code coverage

kcov provides code coverage collection for coverage-guided fuzzing
(randomized testing). Coverage-guided fuzzing is a testing technique
that uses coverage feedback to determine new interesting inputs to a
system. A notable user-space example is AFL
(http://lcamtuf.coredump.cx/afl/). However, this technique is not
widely used for kernel testing due to missing compiler and kernel
support.

kcov does not aim to collect as much coverage as possible. It aims to
collect more or less stable coverage that is function of syscall inputs.
To achieve this goal it does not collect coverage in soft/hard
interrupts and instrumentation of some inherently non-deterministic or
non-interesting parts of kernel is disbled (e.g. scheduler, locking).

Currently there is a single coverage collection mode (tracing), but the
API anticipates additional collection modes. Initially I also
implemented a second mode which exposes coverage in a fixed-size hash
table of counters (what Quentin used in his original patch). I've
dropped the second mode for simplicity.

This patch adds the necessary support on kernel side. The complimentary
compiler support was added in gcc revision 231296.

We've used this support to build syzkaller system call fuzzer, which has
found 90 kernel bugs in just 2 months:

https://github.com/google/syzkaller/wiki/Found-Bugs

We've also found 30+ bugs in our internal systems with syzkaller.
Another (yet unexplored) direction where kcov coverage would greatly
help is more traditional "blob mutation". For example, mounting a
random blob as a filesystem, or receiving a random blob over wire.

Why not gcov. Typical fuzzing loop looks as follows: (1) reset
coverage, (2) execute a bit of code, (3) collect coverage, repeat. A
typical coverage can be just a dozen of basic blocks (e.g. an invalid
input). In such context gcov becomes prohibitively expensive as
reset/collect coverage steps depend on total number of basic
blocks/edges in program (in case of kernel it is about 2M). Cost of
kcov depends only on number of executed basic blocks/edges. On top of
that, kernel requires per-thread coverage because there are always
background threads and unrelated processes that also produce coverage.
With inlined gcov instrumentation per-thread coverage is not possible.

kcov exposes kernel PCs and control flow to user-space which is
insecure. But debugfs should not be mapped as user accessible.

Based on a patch by Quentin Casasnovas.

[[email protected]: make task_struct.kcov_mode have type `enum kcov_mode']
[[email protected]: unbreak allmodconfig]
[[email protected]: follow x86 Makefile layout standards]
Signed-off-by: Dmitry Vyukov <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Cc: syzkaller <[email protected]>
Cc: Vegard Nossum <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Tavis Ormandy <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Quentin Casasnovas <[email protected]>
Cc: Kostya Serebryany <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Alexander Potapenko <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: David Drysdale <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Andrey Ryabinin <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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x86, irq: Move HT IRQ related code from io_apic.c into htirq.c

Create arch/x86/kernel/apic/htirq.c to host Hypertransport IRQ related
code, preparing for enabling hierarchy irqdomain.

Signed-off-by

x86, irq: Move HT IRQ related code from io_apic.c into htirq.c

Create arch/x86/kernel/apic/htirq.c to host Hypertransport IRQ related
code, preparing for enabling hierarchy irqdomain.

Signed-off-by: Jiang Liu <[email protected]>
Cc: Konrad Rzeszutek Wilk <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Rafael J. Wysocki <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Yinghai Lu <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Grant Likely <[email protected]>
Cc: Prarit Bhargava <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

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x86, irq: Move PCI MSI related code from io_apic.c into msi.c

Create arch/x86/kernel/apic/msi.c to host MSI related code,
preparing for enabling hierarchy irqdomain.

Signed-off-by: Jiang Liu <jiang

x86, irq: Move PCI MSI related code from io_apic.c into msi.c

Create arch/x86/kernel/apic/msi.c to host MSI related code,
preparing for enabling hierarchy irqdomain.

Signed-off-by: Jiang Liu <[email protected]>
Cc: Konrad Rzeszutek Wilk <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Rafael J. Wysocki <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Yinghai Lu <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Rafael J. Wysocki <[email protected]>
Cc: Grant Likely <[email protected]>
Cc: Prarit Bhargava <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

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x86, irq: Move local APIC related code from io_apic.c into vector.c

Create arch/x86/kernel/apic/vector.c to host local APIC related code,
prepare for making MSI/HT_IRQ independent of IOAPIC.

Signed

x86, irq: Move local APIC related code from io_apic.c into vector.c

Create arch/x86/kernel/apic/vector.c to host local APIC related code,
prepare for making MSI/HT_IRQ independent of IOAPIC.

Signed-off-by: Jiang Liu <[email protected]>
Cc: Konrad Rzeszutek Wilk <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Rafael J. Wysocki <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Yinghai Lu <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Prarit Bhargava <[email protected]>
Cc: Grant Likely <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

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x86, platforms: Remove NUMAQ

The NUMAQ support seems to be unmaintained, remove it.

Cc: Paul Gortmaker <[email protected]>
Cc: David Rientjes <[email protected]>
Acked-by: Paul E. McKe

x86, platforms: Remove NUMAQ

The NUMAQ support seems to be unmaintained, remove it.

Cc: Paul Gortmaker <[email protected]>
Cc: David Rientjes <[email protected]>
Acked-by: Paul E. McKenney <[email protected]>
Signed-off-by: H. Peter Anvin <[email protected]>
Link: http://lkml.kernel.org/r/n/[email protected]

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x86, apic: Remove support for IBM Summit/EXA chipset

There should no longer be any IBM x440 systems or those using the
Summit/EXA chipset out in the wild, so remove support for it.

We've done our d

x86, apic: Remove support for IBM Summit/EXA chipset

There should no longer be any IBM x440 systems or those using the
Summit/EXA chipset out in the wild, so remove support for it.

We've done our due diligence in reaching out to any contact information
listed for this chipset and no indication was given that it should be
kept around.

Signed-off-by: David Rientjes <[email protected]>

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x86, apic: Remove support for ia32-based Unisys ES7000

There should no longer be any ia32-based Unisys ES7000 systems out in
the wild, so remove support for it.

We've done our due diligence in reac

x86, apic: Remove support for ia32-based Unisys ES7000

There should no longer be any ia32-based Unisys ES7000 systems out in
the wild, so remove support for it.

We've done our due diligence in reaching out to any contact information
listed for this system and no indication was given that it should be
kept around.

Signed-off-by: David Rientjes <[email protected]>

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trace,x86: Move creation of irq tracepoints from apic.c to irq.c

Compiling without CONFIG_X86_LOCAL_APIC set, apic.c will not be
compiled, and the irq tracepoints will not be created via the
CREATE_

trace,x86: Move creation of irq tracepoints from apic.c to irq.c

Compiling without CONFIG_X86_LOCAL_APIC set, apic.c will not be
compiled, and the irq tracepoints will not be created via the
CREATE_TRACE_POINTS macro. When CONFIG_X86_LOCAL_APIC is not set,
we get the following build error:

LD init/built-in.o
arch/x86/built-in.o: In function `trace_x86_platform_ipi_entry':
linux-test.git/arch/x86/include/asm/trace/irq_vectors.h:66: undefined reference to `__tracepoint_x86_platform_ipi_entry'
arch/x86/built-in.o: In function `trace_x86_platform_ipi_exit':
linux-test.git/arch/x86/include/asm/trace/irq_vectors.h:66: undefined reference to `__tracepoint_x86_platform_ipi_exit'
arch/x86/built-in.o: In function `trace_irq_work_entry':
linux-test.git/arch/x86/include/asm/trace/irq_vectors.h:72: undefined reference to `__tracepoint_irq_work_entry'
arch/x86/built-in.o: In function `trace_irq_work_exit':
linux-test.git/arch/x86/include/asm/trace/irq_vectors.h:72: undefined reference to `__tracepoint_irq_work_exit'
arch/x86/built-in.o:(__jump_table+0x8): undefined reference to `__tracepoint_x86_platform_ipi_entry'
arch/x86/built-in.o:(__jump_table+0x14): undefined reference to `__tracepoint_x86_platform_ipi_exit'
arch/x86/built-in.o:(__jump_table+0x20): undefined reference to `__tracepoint_irq_work_entry'
arch/x86/built-in.o:(__jump_table+0x2c): undefined reference to `__tracepoint_irq_work_exit'
make[1]: *** [vmlinux] Error 1
make: *** [sub-make] Error 2

As irq.c is always compiled for x86, it is a more appropriate location
to create the irq tracepoints.

Cc: Seiji Aguchi <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>

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x86, trace: Add irq vector tracepoints

[Purpose of this patch]

As Vaibhav explained in the thread below, tracepoints for irq vectors
are useful.

http://www.spinics.net/lists/mm-commits/msg85707.ht

x86, trace: Add irq vector tracepoints

[Purpose of this patch]

As Vaibhav explained in the thread below, tracepoints for irq vectors
are useful.

http://www.spinics.net/lists/mm-commits/msg85707.html

<snip>
The current interrupt traces from irq_handler_entry and irq_handler_exit
provide when an interrupt is handled. They provide good data about when
the system has switched to kernel space and how it affects the currently
running processes.

There are some IRQ vectors which trigger the system into kernel space,
which are not handled in generic IRQ handlers. Tracing such events gives
us the information about IRQ interaction with other system events.

The trace also tells where the system is spending its time. We want to
know which cores are handling interrupts and how they are affecting other
processes in the system. Also, the trace provides information about when
the cores are idle and which interrupts are changing that state.
<snip>

On the other hand, my usecase is tracing just local timer event and
getting a value of instruction pointer.

I suggested to add an argument local timer event to get instruction pointer before.
But there is another way to get it with external module like systemtap.
So, I don't need to add any argument to irq vector tracepoints now.

[Patch Description]

Vaibhav's patch shared a trace point ,irq_vector_entry/irq_vector_exit, in all events.
But there is an above use case to trace specific irq_vector rather than tracing all events.
In this case, we are concerned about overhead due to unwanted events.

So, add following tracepoints instead of introducing irq_vector_entry/exit.
so that we can enable them independently.
- local_timer_vector
- reschedule_vector
- call_function_vector
- call_function_single_vector
- irq_work_entry_vector
- error_apic_vector
- thermal_apic_vector
- threshold_apic_vector
- spurious_apic_vector
- x86_platform_ipi_vector

Also, introduce a logic switching IDT at enabling/disabling time so that a time penalty
makes a zero when tracepoints are disabled. Detailed explanations are as follows.
- Create trace irq handlers with entering_irq()/exiting_irq().
- Create a new IDT, trace_idt_table, at boot time by adding a logic to
_set_gate(). It is just a copy of original idt table.
- Register the new handlers for tracpoints to the new IDT by introducing
macros to alloc_intr_gate() called at registering time of irq_vector handlers.
- Add checking, whether irq vector tracing is on/off, into load_current_idt().
This has to be done below debug checking for these reasons.
- Switching to debug IDT may be kicked while tracing is enabled.
- On the other hands, switching to trace IDT is kicked only when debugging
is disabled.

In addition, the new IDT is created only when CONFIG_TRACING is enabled to avoid being
used for other purposes.

Signed-off-by: Seiji Aguchi <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: H. Peter Anvin <[email protected]>
Cc: Steven Rostedt <[email protected]>

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x86: Add NumaChip support

Adds support for Numascale NumaChip large-SMP systems. It is
needed to enable the booting of more than ~168 cores.

v2:
- [Steffen] enumerate only accessible northbridges

x86: Add NumaChip support

Adds support for Numascale NumaChip large-SMP systems. It is
needed to enable the booting of more than ~168 cores.

v2:
- [Steffen] enumerate only accessible northbridges
- [Daniel] rediffed and validated against 3.1-rc10

v3:
- [Daniel] use x86_init core numbering override
- [Daniel] cleanups as per feedback

v4:
- [Daniel] use updated x86_cpuinit override

v5:
- drop disabling interrupts locally, as ISR write is atomic; drop delay
- added read-mostly annotations where appropriate
- require CONFIG_SMP, so drop conditional path

Workload tested on 96 cores/16 sockets.

Signed-off-by: Steffen Persvold <[email protected]>
Signed-off-by: Daniel J Blueman <[email protected]>
Cc: Jesse Barnes <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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x86, apic: Introduce .apicdrivers section to find the list of apic drivers

This will pave the way for each apic driver to be self-contained
and eliminate the need for apic_probe[].

Order in which a

x86, apic: Introduce .apicdrivers section to find the list of apic drivers

This will pave the way for each apic driver to be self-contained
and eliminate the need for apic_probe[].

Order in which apic drivers are listed in the .apicdrivers
section is important, as this determines the apic probe order.
And this is enforced by the ordering of apic driver files in the
Makefile and the macros apic_driver()/apic_drivers().

Signed-off-by: Suresh Siddha <[email protected]>
Tested-by: Cyrill Gorcunov <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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x86, nmi_watchdog: Remove the old nmi_watchdog

Now that we have a new nmi_watchdog that is more generic and
sits on top of the perf subsystem, we really do not need the old
nmi_watchdog any more.

I

x86, nmi_watchdog: Remove the old nmi_watchdog

Now that we have a new nmi_watchdog that is more generic and
sits on top of the perf subsystem, we really do not need the old
nmi_watchdog any more.

In addition, the old nmi_watchdog doesn't really work if you are
using the default clocksource, hpet. The old nmi_watchdog code
relied on local apic interrupts to determine if the cpu is still
alive. With hpet as the clocksource, these interrupts don't
increment any more and the old nmi_watchdog triggers false
postives.

This piece removes the old nmi_watchdog code and stubs out any
variables and functions calls. The stubs are the same ones used
by the new nmi_watchdog code, so it should be well tested.

Signed-off-by: Don Zickus <[email protected]>
Cc: [email protected]
Cc: [email protected]
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

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lockup_detector: Cross arch compile fixes

Combining the softlockup and hardlockup code causes watchdog.c
to build even without the hardlockup detection support.

So if an arch, that has the previous

lockup_detector: Cross arch compile fixes

Combining the softlockup and hardlockup code causes watchdog.c
to build even without the hardlockup detection support.

So if an arch, that has the previous and the new nmi watchdog
implementations cohabiting, wants to know if the generic one
is in use, CONFIG_LOCKUP_DETECTOR is not a reliable check.
We need to use CONFIG_HARDLOCKUP_DETECTOR instead.

Fixes:
kernel/built-in.o: In function `touch_nmi_watchdog':
(.text+0x449bc): multiple definition of `touch_nmi_watchdog'
arch/sparc/kernel/built-in.o:(.text+0x11b28): first defined here

Signed-off-by: Don Zickus <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Don Zickus <[email protected]>
Cc: Cyrill Gorcunov <[email protected]>
LKML-Reference: <[email protected]>
[ use CONFIG_HARDLOCKUP_DETECTOR instead of CONFIG_PERF_EVENTS_NMI]
Signed-off-by: Frederic Weisbecker <[email protected]>

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lockup_detector: Combine nmi_watchdog and softlockup detector

The new nmi_watchdog (which uses the perf event subsystem) is very
similar in structure to the softlockup detector. Using Ingo's
sugges

lockup_detector: Combine nmi_watchdog and softlockup detector

The new nmi_watchdog (which uses the perf event subsystem) is very
similar in structure to the softlockup detector. Using Ingo's
suggestion, I combined the two functionalities into one file:
kernel/watchdog.c.

Now both the nmi_watchdog (or hardlockup detector) and softlockup
detector sit on top of the perf event subsystem, which is run every
60 seconds or so to see if there are any lockups.

To detect hardlockups, cpus not responding to interrupts, I
implemented an hrtimer that runs 5 times for every perf event
overflow event. If that stops counting on a cpu, then the cpu is
most likely in trouble.

To detect softlockups, tasks not yielding to the scheduler, I used the
previous kthread idea that now gets kicked every time the hrtimer fires.
If the kthread isn't being scheduled neither is anyone else and the
warning is printed to the console.

I tested this on x86_64 and both the softlockup and hardlockup paths
work.

V2:
- cleaned up the Kconfig and softlockup combination
- surrounded hardlockup cases with #ifdef CONFIG_PERF_EVENTS_NMI
- seperated out the softlockup case from perf event subsystem
- re-arranged the enabling/disabling nmi watchdog from proc space
- added cpumasks for hardlockup failure cases
- removed fallback to soft events if no PMU exists for hard events

V3:
- comment cleanups
- drop support for older softlockup code
- per_cpu cleanups
- completely remove software clock base hardlockup detector
- use per_cpu masking on hard/soft lockup detection
- #ifdef cleanups
- rename config option NMI_WATCHDOG to LOCKUP_DETECTOR
- documentation additions

V4:
- documentation fixes
- convert per_cpu to __get_cpu_var
- powerpc compile fixes

V5:
- split apart warn flags for hard and soft lockups

TODO:
- figure out how to make an arch-agnostic clock2cycles call
(if possible) to feed into perf events as a sample period

[fweisbec: merged conflict patch]

Signed-off-by: Don Zickus <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Cyrill Gorcunov <[email protected]>
Cc: Eric Paris <[email protected]>
Cc: Randy Dunlap <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Frederic Weisbecker <[email protected]>

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nmi_watchdog: Config option to enable new nmi_watchdog

These are the bits that enable the new nmi_watchdog and safely
isolate the old nmi_watchdog. Only one or the other can run,
not both at the sa

nmi_watchdog: Config option to enable new nmi_watchdog

These are the bits that enable the new nmi_watchdog and safely
isolate the old nmi_watchdog. Only one or the other can run,
not both at the same time.

Signed-off-by: Don Zickus <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

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x86, apic: Introduce the NOOP apic driver

Introduce NOOP APIC driver. We should use it in case if apic was
disabled due to hardware of software/firmware problems (including
user requested to disable

x86, apic: Introduce the NOOP apic driver

Introduce NOOP APIC driver. We should use it in case if apic was
disabled due to hardware of software/firmware problems (including
user requested to disable it case).

The driver is attempting to catch any inappropriate apic operation
call with warning issue.

Also it is possible to use some apic operation like IPI calls,
read/write without checking for apic presence which should make
callers code easier.

Signed-off-by: Cyrill Gorcunov <[email protected]>
Cc: [email protected]
Cc: [email protected]
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

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x86, apic: separate 32-bit setup functionality out of apic_32.c

Impact: build fix, cleanup

A couple of arch setup callbacks were mistakenly in apic_32.c, breaking
the build.

Also simplify the code

x86, apic: separate 32-bit setup functionality out of apic_32.c

Impact: build fix, cleanup

A couple of arch setup callbacks were mistakenly in apic_32.c, breaking
the build.

Also simplify the code a bit.

Signed-off-by: Ingo Molnar <[email protected]>

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x86, apic: move remaining APIC drivers to arch/x86/kernel/apic/*

Move the 32-bit extended-arch APIC drivers to arch/x86/kernel/apic/
too, and rename apic_64.c to probe_64.c.

Signed-off-by: Ingo Mol

x86, apic: move remaining APIC drivers to arch/x86/kernel/apic/*

Move the 32-bit extended-arch APIC drivers to arch/x86/kernel/apic/
too, and rename apic_64.c to probe_64.c.

Signed-off-by: Ingo Molnar <[email protected]>

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x86, apic: move APIC drivers to arch/x86/kernel/apic/*

arch/x86/kernel/ is getting a bit crowded, and the APIC
drivers are scattered into various different files.

Move them to arch/x86/kernel/apic/

x86, apic: move APIC drivers to arch/x86/kernel/apic/*

arch/x86/kernel/ is getting a bit crowded, and the APIC
drivers are scattered into various different files.

Move them to arch/x86/kernel/apic/*, and also remove
the 'gen' prefix from those which had it.

Also move APIC related functionality: the IO-APIC driver,
the NMI and the IPI code.

Signed-off-by: Ingo Molnar <[email protected]>

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