Subject: devmem, x86: fix rename of CONFIG_NONPROMISC_DEVMEM
From: Arjan van de Ven <arjan@infradead.org>
Date: Sat, 19 Jul 2008 15:47:17 -0700

CONFIG_NONPROMISC_DEVMEM was a rather confusing name -

Subject: devmem, x86: fix rename of CONFIG_NONPROMISC_DEVMEM
From: Arjan van de Ven <arjan@infradead.org>
Date: Sat, 19 Jul 2008 15:47:17 -0700

CONFIG_NONPROMISC_DEVMEM was a rather confusing name - but renaming it
to CONFIG_PROMISC_DEVMEM causes problems on architectures that do not
support this feature; this patch renames it to CONFIG_STRICT_DEVMEM,
so that architectures can opt-in into it.

( the polarity of the option is still the same as it was originally; it
needs to be for now to not break architectures that don't have the
infastructure yet to support this feature)

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: "V.Radhakrishnan" <rk@atr-labs.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---

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x86: re-enable OPTIMIZE_INLINING

re-enable OPTIMIZE_INLINING more widely. Jeff Dike fixed the remaining
outstanding issue in this commit:

| commit 4f81c5350b44bcc501ab6f8a089b16d064b4d2f6
| Author:

x86: re-enable OPTIMIZE_INLINING

re-enable OPTIMIZE_INLINING more widely. Jeff Dike fixed the remaining
outstanding issue in this commit:

| commit 4f81c5350b44bcc501ab6f8a089b16d064b4d2f6
| Author: Jeff Dike <jdike@addtoit.com>
| Date: Mon Jul 7 13:36:56 2008 -0400
|
| [UML] fix gcc ICEs and unresolved externs
[...]
| This patch reintroduces unit-at-a-time for gcc >= 4.0, bringing back the
| possibility of Uli's crash. If that happens, we'll debug it.

it's still default-off and thus opt-in.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

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x86: rename CONFIG_NONPROMISC_DEVMEM to CONFIG_PROMISC_DEVMEM

Linus observed:

> The real bug is that we shouldn't have "double negatives", and
> certainly not negative config options. Making that "

x86: rename CONFIG_NONPROMISC_DEVMEM to CONFIG_PROMISC_DEVMEM

Linus observed:

> The real bug is that we shouldn't have "double negatives", and
> certainly not negative config options. Making that "promiscuous
> /dev/mem" option a negated thing as a config option was bad.

right ... lets rename this option. There should never be a negation
in config options.

[ that reminds me of CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER, but that
is for another commit ;-) ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>

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x86: MMIOTRACE should not default to on

Even the help-text makes it clear that normal people shouldn't enable
it.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

x86: cleanup early per cpu variables/accesses v4

* Introduce a new PER_CPU macro called "EARLY_PER_CPU". This is
used by some per_cpu variables that are initialized and accessed
before th

x86: cleanup early per cpu variables/accesses v4

* Introduce a new PER_CPU macro called "EARLY_PER_CPU". This is
used by some per_cpu variables that are initialized and accessed
before there are per_cpu areas allocated.

["Early" in respect to per_cpu variables is "earlier than the per_cpu
areas have been setup".]

This patchset adds these new macros:

DEFINE_EARLY_PER_CPU(_type, _name, _initvalue)
EXPORT_EARLY_PER_CPU_SYMBOL(_name)
DECLARE_EARLY_PER_CPU(_type, _name)

early_per_cpu_ptr(_name)
early_per_cpu_map(_name, _idx)
early_per_cpu(_name, _cpu)

The DEFINE macro defines the per_cpu variable as well as the early
map and pointer. It also initializes the per_cpu variable and map
elements to "_initvalue". The early_* macros provide access to
the initial map (usually setup during system init) and the early
pointer. This pointer is initialized to point to the early map
but is then NULL'ed when the actual per_cpu areas are setup. After
that the per_cpu variable is the correct access to the variable.

The early_per_cpu() macro is not very efficient but does show how to
access the variable if you have a function that can be called both
"early" and "late". It tests the early ptr to be NULL, and if not
then it's still valid. Otherwise, the per_cpu variable is used
instead:

#define early_per_cpu(_name, _cpu) \
(early_per_cpu_ptr(_name) ? \
early_per_cpu_ptr(_name)[_cpu] : \
per_cpu(_name, _cpu))

A better method is to actually check the pointer manually. In the
case below, numa_set_node can be called both "early" and "late":

void __cpuinit numa_set_node(int cpu, int node)
{
int *cpu_to_node_map = early_per_cpu_ptr(x86_cpu_to_node_map);

if (cpu_to_node_map)
cpu_to_node_map[cpu] = node;
else
per_cpu(x86_cpu_to_node_map, cpu) = node;
}

* Add a flag "arch_provides_topology_pointers" that indicates pointers
to topology cpumask_t maps are available. Otherwise, use the function
returning the cpumask_t value. This is useful if cpumask_t set size
is very large to avoid copying data on to/off of the stack.

* The coverage of CONFIG_DEBUG_PER_CPU_MAPS has been increased while
the non-debug case has been optimized a bit.

* Remove an unreferenced compiler warning in drivers/base/topology.c

* Clean up #ifdef in setup.c

For inclusion into sched-devel/latest tree.

Based on:
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
+ sched-devel/latest .../mingo/linux-2.6-sched-devel.git

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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x86: let MPS support be selectable, v2

v2: seperate "fix for compiling when MPPARSE is not set" to another patch
make X86_MPPARSE to be selectable only when acpi is set and
X86_MPPARSE will

x86: let MPS support be selectable, v2

v2: seperate "fix for compiling when MPPARSE is not set" to another patch
make X86_MPPARSE to be selectable only when acpi is set and
X86_MPPARSE will be set if acpi is not set.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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x86: config option to disable info from decompression of the kernel

This patch allows the disabling of decompression messages during
x86 bootup.

Signed-off-by: Ben Collins <ben.collins@canonical.co

x86: config option to disable info from decompression of the kernel

This patch allows the disabling of decompression messages during
x86 bootup.

Signed-off-by: Ben Collins <ben.collins@canonical.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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x86: fix CONFIG_NONPROMISC_DEVMEM prompt and help text

Here is an attempt to translate the prompt and help text into something
which is legible and, as a bonus, correct.

Signed-off-by: Stefan Richt

x86: fix CONFIG_NONPROMISC_DEVMEM prompt and help text

Here is an attempt to translate the prompt and help text into something
which is legible and, as a bonus, correct.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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x86: allow MPPARSE to be deselected in SMP configs

x86/mmiotrace: uses/depends on PCI

Don't try to build mmiotrace when CONFIG_PCI=n.

next-20080416/kernel/trace/trace_mmiotrace.c: In function 'mmio_print_pcidev':
next-20080416/kernel/trace/trace_mm

x86/mmiotrace: uses/depends on PCI

Don't try to build mmiotrace when CONFIG_PCI=n.

next-20080416/kernel/trace/trace_mmiotrace.c: In function 'mmio_print_pcidev':
next-20080416/kernel/trace/trace_mmiotrace.c:62: error: implicit declaration of function 'pci_dev_driver'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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mmiotrace: add user documentation

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

ftrace: mmiotrace, updates

here is a patch that makes mmiotrace work almost well within the tracing
framework. The patch applies on top of my previous patch. I have my own
output formatting in place

ftrace: mmiotrace, updates

here is a patch that makes mmiotrace work almost well within the tracing
framework. The patch applies on top of my previous patch. I have my own
output formatting in place now.

Summary of changes:
- fix the NULL dereference that was due to not calling tracing_reset()
- add print_line() callback into struct tracer
- implement print_line() for mmiotrace, producing up-to-spec text
- add my output header, but that is not really called in the right place
- rewrote the main structs in mmiotrace
- added two new trace entry types: TRACE_MMIO_RW and TRACE_MMIO_MAP
- made some functions in trace.c non-static
- check current==NULL in tracing_generic_entry_update()
- fix(?) comparison in trace_seq_printf()

Things seem to work fine except a few issues. Markers (text lines injected
into mmiotrace log) are missing, I did not feel hacking them in before we
have variable length entries. My output header is printed only for 'trace'
file, but not 'trace_pipe'. For some reason, despite my quick fix,
iter->trace is NULL in print_trace_line() when called from 'trace_pipe'
file, which means I don't get proper output formatting.

I only tried by loading nouveau.ko, which just detects the card, and that
is traced fine. I didn't try further. Map, two reads and unmap. Works
perfectly.

I am missing the information about overflows, I'd prefer to have a
counter for lost events. I didn't try, but I guess currently there is no
way of knowning when it overflows?

So, not too far from being fully operational, it seems :-)
And looking at the diffstat, there also is some 700-900 lines of user space
code that just became obsolete.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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ftrace: add mmiotrace plugin

On Sat, 22 Mar 2008 13:07:47 +0100
Ingo Molnar <mingo@elte.hu> wrote:

> > > i'd suggest the following: pull x86.git and sched-devel.git into a
> > > single tree [the tw

ftrace: add mmiotrace plugin

On Sat, 22 Mar 2008 13:07:47 +0100
Ingo Molnar <mingo@elte.hu> wrote:

> > > i'd suggest the following: pull x86.git and sched-devel.git into a
> > > single tree [the two will combine without rejects]. Then try to add a
> > > kernel/tracing/trace_mmiotrace.c ftrace plugin. The trace_sysprof.c
> > > plugin might be a good example.
> >
> > I did this and now I have mmiotrace enabled/disabled via the tracing
> > framework (what do we call this, since ftrace is one of the tracers?).
>
> cool! could you send the patches for that? (even if they are not fully
> functional yet)

Patch attached in the end. Nice to see how much code disappeared. I tried
to mark all the features I had to break with XXX-comments.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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x86: mmiotrace, preview 2

Kconfig.debug, Makefile and testmmiotrace.c style fixes.
Use real mutex instead of mutex.
Fix failure path in register probe func.
kmmio: RCU read-locked over single steppi

x86: mmiotrace, preview 2

Kconfig.debug, Makefile and testmmiotrace.c style fixes.
Use real mutex instead of mutex.
Fix failure path in register probe func.
kmmio: RCU read-locked over single stepping.
Generate mapping id's.
Make mmio-mod.c built-in and rewrite its locking.
Add debugfs file to enable/disable mmiotracing.
kmmio: use irqsave spinlocks.
Lots of cleanups in mmio-mod.c
Marker file moved from /proc into debugfs.
Call mmiotrace entrypoints directly from ioremap.c.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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x86: explicit call to mmiotrace in do_page_fault()

The custom page fault handler list is replaced with a single function
pointer. All related functions and variables are renamed for
mmiotrace.

Sign

x86: explicit call to mmiotrace in do_page_fault()

The custom page fault handler list is replaced with a single function
pointer. All related functions and variables are renamed for
mmiotrace.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: pq@iki.fi
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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x86: mmiotrace - trace memory mapped IO

Mmiotrace is a tool for trapping memory mapped IO (MMIO) accesses within
the kernel. It is used for debugging and especially for reverse
engineering evil bina

x86: mmiotrace - trace memory mapped IO

Mmiotrace is a tool for trapping memory mapped IO (MMIO) accesses within
the kernel. It is used for debugging and especially for reverse
engineering evil binary drivers.

Mmiotrace works by wrapping the ioremap family of kernel functions and
marking the returned pages as not present. Access to the IO memory
triggers a page fault, which will be handled by mmiotrace's custom page
fault handler. This will single-step the faulted instruction with the
MMIO page marked as present. Access logs are directed to user space via
relay and debug_fs.

This page fault approach is necessary, because binary drivers have
readl/writel etc. calls inlined and therefore extremely difficult to
trap with with e.g. kprobes.

This patch depends on the custom page fault handlers patch.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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x86: add a list for custom page fault handlers.

Provides kernel modules a way to register custom page fault handlers.
On every page fault this will call a list of registered functions. The
functions

x86: add a list for custom page fault handlers.

Provides kernel modules a way to register custom page fault handlers.
On every page fault this will call a list of registered functions. The
functions may handle the fault and force do_page_fault() to return
immediately.

This functionality is similar to the now removed page fault notifiers.
Custom page fault handlers are used by debugging and reverse engineering
tools. Mmiotrace is one such tool and a patch to add it into the tree
will follow.

The custom page fault handlers are called earlier in do_page_fault()
than the page fault notifiers were.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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x86: Mark OPTIMIZE_INLINING broken

So Ingo finally did figure out why UML broke with this option: UML
passes gcc the -fno-unit-at-a-time flag, and apparently that wreaks
havoc with gcc's inlining.

x86: Mark OPTIMIZE_INLINING broken

So Ingo finally did figure out why UML broke with this option: UML
passes gcc the -fno-unit-at-a-time flag, and apparently that wreaks
havoc with gcc's inlining.

We could turn off -fno-unit-at-a-time for UML for gcc4+ (which is what
x86 does), but there's bad blood about this whole option, and it does
show that the thing is just fragile as heck.

So let tempers cool, and disable the thing, and we can revisit the
decision later.

Cc: Adrian Bunk <bunk@kernel.org>
Cc: David Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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x86: 8K stacks by default

Switch back to 8K stacks as the safer default. Out-of-memory
situations are less problematic than silent and hard to debug
stack corruption.

Signed-off-by: Ingo Molnar <mi

x86: 8K stacks by default

Switch back to 8K stacks as the safer default. Out-of-memory
situations are less problematic than silent and hard to debug
stack corruption.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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x86: optimize inlining off

default to inline optimizing off.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

x86: Kconfig fix

Andrew noticed that OPTIMIZE_INLINING appeared in the toplevel
menu - fix it.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Sign

x86: Kconfig fix

Andrew noticed that OPTIMIZE_INLINING appeared in the toplevel
menu - fix it.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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x86: add optimized inlining

add CONFIG_OPTIMIZE_INLINING=y.

allow gcc to optimize the kernel image's size by uninlining
functions that have been marked 'inline'. Previously gcc was
forced by Linux

x86: add optimized inlining

add CONFIG_OPTIMIZE_INLINING=y.

allow gcc to optimize the kernel image's size by uninlining
functions that have been marked 'inline'. Previously gcc was
forced by Linux to always-inline these functions via a gcc
attribute:

#define inline inline __attribute__((always_inline))

Especially when the user has already selected
CONFIG_OPTIMIZE_FOR_SIZE=y this can make a huge difference in
kernel image size (using a standard Fedora .config):

text data bss dec hex filename
5613924 562708 3854336 10030968 990f78 vmlinux.before
5486689 562708 3854336 9903733 971e75 vmlinux.after

that's a 2.3% text size reduction (!).

Signed-off-by: Ingo Molnar <mingo@elte.hu>

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/dev/mem: make promisc the default

default to the old semantics.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

x86: introduce /dev/mem restrictions with a config option

This patch introduces a restriction on /dev/mem: Only non-memory can be
read or written unless the newly introduced config option is set.

T

x86: introduce /dev/mem restrictions with a config option

This patch introduces a restriction on /dev/mem: Only non-memory can be
read or written unless the newly introduced config option is set.

The X server needs access to /dev/mem for the PCI space, but it doesn't need
access to memory; both the file permissions and SELinux permissions of /dev/mem
just make X effectively super-super powerful. With the exception of the
BIOS area, there's just no valid app that uses /dev/mem on actual memory.
Other popular users of /dev/mem are rootkits and the like.
(note: mmap access of memory via /dev/mem was already not allowed since
a really long time)

People who want to use /dev/mem for kernel debugging can enable the config
option.

The restrictions of this patch have been in the Fedora and RHEL kernels for
at least 4 years without any problems.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

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x86: 4kstacks default

Signed-off-by: Ingo Molnar <mingo@elte.hu>