Remove an unneeded WSET() which snuck in there.

The sysrq-T output currently tries to display the mimimum amount of free
stack which each task has ever had available.  It has been busted for years,
because we forgot to zero out the stack when it is first created.

Fix that up, adding a conig option for it.

If the option is disabled, or the arch is not x86 then the free stack usage
will display as zero.

From: Herbert Poetzl <herbert@13thfloor.at>

sys_ptrace() for v850, if pid == 1, doesn't put the struct task_struct
(child), the following patch should fix that ...

From: Arjan van de Ven <arjanv@redhat.com>

fix obvious non-C-standard stubs on ppc64

into ppc970.osdl.org:/home/torvalds/v2.5/linux

into ppc970.osdl.org:/home/torvalds/v2.5/linux

into redhat.com:/spare/repo/net-drivers-2.5

This fixes the behaviour of the pmac "macio" IDE driver when a DMA
transfer happen to get less data out of the device than expected when
setting up the DMA commands (the device underruns).  This is very common
with recent ATAPI stuffs and used to cause problem & disable DMA.  This
patch fixes the way we handle that condition, thus also fixing DVD
burning on a bunch of recent pmacs. 

Some barriers between setting up the DMA regions and writing the
descriptor addresses would be most useful.

I had some in my 2.4 version but they got lost someway, probably me not
properly merging with davem at this point.  The 970 is definitely more
agressive at re-ordering stores than previous CPUs...

Here is a patch adding some (probably too much, but better safe than
sorry).

into kroah.com:/home/greg/linux/BK/usb-2.6

into ppc970.osdl.org:/home/torvalds/v2.5/linux

People ask how to write the CIS on a SmartMedia card using an sddr09
reader/writer.  The patch below documents the required command (but does
not add the code).

Two years ago or so I used this to fix the CIS on a card that my camera no
longer wanted to accept.  A Linux utility to do this might be useful, but
the problem always is that we do not really have a good mechanism.

How does one tell a driver that it has to do something special?  Add yet
another ioctl?

The main item in this patch is the conversion of the UHCI driver from
using the old usb.h logging macros to the new driver-model dev_xxx
macros.

There are a few other minor changes too: updated version number, author,
copyright, and maintainer information, removed some unneeded error
messages, added some line breaks, added a convenience macro for the device
pointer.

On Fri, 20 Feb 2004, Gustavo Guillermo wrote:

> Ok, I tested the patch, The camera works, just as in the old Kernel,
> Thanks, I'm including as an atachment the /proc/bus/usb/devices from
> kernel 2.4.x and 2.6.x, and the kernel log for 2.4.x, but ooops, I forgot
> to biold 2.4.x with full debug, if someone need it I will do.
>
> Please include this FIX in the Next Release.

Greg, I now feel confident that this patch should be applied.

On Thu, 19 Feb 2004, Agustin De Igartua wrote:

> Initializing USB Mass Storage driver...
> usb-storage: This device (04e6,0002,0100 S 06 P 50) has unneeded SubClass and Protocol entries in unusual_devs.h
>    Please send a copy of this message to <linux-usb-devel@lists.sourceforge.net>scsi0 : SCSI emulation for USB Mass Storage devices

Thank you for sending this in.  Greg, here's the patch.

There are no known failures due to this bug, but it's clearly a bug and
given the right compiler, it could trigger and lead to bad stack traces etc.

I incorporated (at least in spirit I hope) hch's suggestions on the fixup code
put in some kfrees that I was missing and static for sn_alloc_pci_sysdata
(thanks Bartlomiej Zolnierkiewicz).  White space clean up.

Cleanup the SN setup.c file.  Add __init and static to functions where
required.

Here is a patch to clean up some of the Altix header files and includes.

I've run the patch past the appropriate people at SGI and they seem happy
with the changes.

From: Arnd Bergmann <arnd@arndb.de>

Christian Bornträger noticed that the kernel can crash after <SysRq>-T.  It
appears that the show_task function gets called for all tasks, which does
not work if one of the tasks is running in a system call on another CPU.
In that case the result of thread_saved_pc and show_stack is undefined and
likely to cause a crash.

For tasks running in user space on other CPUs, show_task() is probably
harmless, but I'm not sure if that's true on all architectures.

The patch below is still racy for tasks that are about to sleep, but it
demonstrates the problem.

show_task() is preinting negative numbers for free stack due to arithmetic
against the wrong pointer.

Fix that up, and clean up a few related things.

show_task still has bogus code which atempts to work out how much stack the
task has ever used - it cannot work because we don't actually zero out the
stack pages when allocating them.  We should fix that, or take it out.

I find this handy sometimes: it makes the oops output include info as to
whether the user has selected CONFIG_PREEMPT, CONFIG_SMP or, particularly,
CONFIG_DEBUG_PAGEALLOC.  It can save one email round-trip.

From: "Martin J. Bligh" <mbligh@aracnet.com>

Make irqbalance into a config option - some people (jgarzik, arjan, etc)
wanted to be able to disable it and do things from userspace instead.  This
patch allows each camp to do their own thing, which seems fair ;-)

From: "Martin J. Bligh" <mbligh@aracnet.com>

Disallow NUMA on the i386 PC subarch (it doesn't work, nor was it intended
to).

From: "Martin J. Bligh" <mbligh@aracnet.com>

Makes sure pfn_to_nid is defined for all combinations of subarches, and that
it's defined before it's used so we don't run into implicit declaration
problems.

From: "Martin J. Bligh" <mbligh@aracnet.com>

Fix pfn_valid for architctures with discontiguous memory.  This only
changes the NUMA definition, and it leaves the NUMA-Q definition as was,
because it's faster that way, it's in hotpaths, and our memory is always
contiguous.

From: Andreas Gruenbacher <agruen@suse.de>

The fix for permission() that makes it compliant with POSIX.1-2001
apparently was lost.  Here is the patch I sent before.  (The relevant lines
from the standard text are cited in
http://www.ussg.iu.edu/hypermail/linux/kernel/0310.2/0286.html.  The fix
proposed in that posting did not handle directories without execute
permissions correctly.)


Make permission check conform to POSIX.1-2001

The access(2) function does not conform to POSIX.1-2001: For root
and a file with no permissions, access(file, MAY_READ|MAY_EXEC)
returns 0 (it should return -1).

drivers/net/bonding/bond_alb.c: In function `bond_alb_xmit':
drivers/net/bonding/bond_alb.c:1188: error: invalid lvalue in assignment

gcc-3.4 incorretly inlines rest_init() into start_kernel(), causing things to
crash when the .text.init section gets unloaded.  Use noinline to prevent
that.

From: Andi Kleen <ak@muc.de>

This patch adds the `noinline' function attribute.  It can be used to
explicitly tell the compiler to not inline functions.

We need this due to what is, IMO, a bug present in gcc-3.4 and current
gcc-3.5 CVS: the compiler is inlining init/main.c:rest_init() inside
init/main.c:start_kernel(), despite the fact that thay are declared to be
placed in different text sections.

From: Andi Kleen <ak@muc.de>

The upcomming gcc 3.4 has a new compilation mode called unit-at-a-time.
What it does is to first load the whole file into memory and then generate
the output. This allows it to use a better inlining strategy, drop unused
static functions and use -mregparm automatically for static functions.

It does not seem to compile significantly slower.

This is also available in some of the 3.3 based "hammer branch"
compilers used in distributions (at least in SuSE and Mandrake)

Some tests show impressive .text shrinkage from unit-at-a-time.

e.g. here is the same kernel compiled with -fno-unit-at-a-time and
-funit-at-a-time with a gcc 3.4 snapshot. The gains are really
impressive:

   text    data     bss     dec     hex filename
4129346  708629  207240 5045215  4cfbdf vmlinux-nounitatatime
3999250  674853  207208 4881311  4a7b9f vmlinux-unitatatime

.text shrinks by over 130KB!. And .data shrinks too.

At first look the numbers look nearly too good to be true, but they have been
verified with several configurations and seem to be real. It looks like
we have a lot of stupid inlines or dead functions. I'm really not
sure why it is that much better. But it's hard to argue with hard
numbers.

[A bloat-o-meter comparision between the two vmlinuxes can be found in
http://www.firstfloor.org/~andi/unit-vs-no-unit.gz . It doesn't show
any obvious candidates unfortunately, just lots of small changes]

With the gcc 3.3-hammer from SuSE 9.0 the gains are a bit smaller, but
still noticeable (>100KB on .text)

This patch enables -funit-at-a-time on ia32 if the compiler is gcc-3.4 or
later.  We had several reports of gcc-3.3 producing very early lockups.

From: Andi Kleen <ak@muc.de>, me.

Using -mregparm=3 shrinks the kernel further:

(compiled with gcc 3.4, without -funit-at-a-time, using the later and
together with -Os shrinks .text even more, making over 700KB difference)

4129346  708629  207240 5045215  4cfbdf vmlinux
3892905  708629  207240 4808774  496046 vmlinux-regparm

This one helps even more, >236KB .text difference. Clearly worth
the effort.

This patch adds an option to use -mregparm=3 while compiling the kernel.  I
did an LTP run and it showed no additional failures over an non regparm
kernel.

According to some gcc developers it should be safe to use in all gccs that
are still supports (2.95 and up)

I didn't make it the default because it will break all binary only modules
(although they can be fixed by adding a wrapper that calls them with
"asmlinkage").  Actually it may be a good idea to make this default with
2.7.1 or somesuch.

We add new kbuild infrastructure: the command

	scripts/gcc-version.sh $(CC)

will print out the version of gcc in a canonical 4-digit form suitable for
performing numerical tests against.
DESC
arch/i386/Makefile,scripts/gcc-version.sh,Makefile small fixes
EDESC
From: Serge Belyshev <33554432@mtu-net.ru>

arch/i386/Makefile:
*  omitted $(KBUILD_SRC)/ in script call.

scripts/gcc-version.sh:
*  GNU tail no longer supports 'tail -1' syntax.

We should consider adding -fweb option:

   vanilla:
   $ size vmlinux
      text    data     bss     dec     hex filename
   3056270  526780  386056 3969106  3c9052 vmlinux

   with -fweb:
   $ size vmlinux
      text    data     bss     dec     hex filename
   3049523  526780  386056 3962359  3c75f7 vmlinux

   Also note 0.1 ... 1.0% speedup in various benchmarks.
   This option is not enabled by default at -O2 because it
   (like -fomit-frame-pointer) makes debugging impossible.

Remove page validity test.  I had a warning in there for a few weeks, no
reports of it happening.

From: Manfred Spraul <manfred@colorfullife.com>

The patch is designed improve the diagnostics which are presented when the
slab memory poison detector triggers.


check_poison_obj checks for write accesses after kfree by comparing the
object contents with the poison value.  The current implementation contains
several flaws:

- it accepts both POISON_BEFORE and POISON_AFTER.  check_poison_obj is
  only called with POISON_AFTER poison bytes.  Fix: only accept
  POISON_AFTER.

- the output is unreadable.  Fix: use hexdump.

- if a large objects is corrupted, then the relevant lines can scroll of
  the screen/dmesg buffer.  Fix: line limit.

- it can access addresses behind the end of the object, which can oops
  with CONFIG_DEBUG_PAGEALLOC.  Fix: bounds checks.

Additionally, the patch contains the following changes:

- rename POISON_BEFORE and POISON_AFTER to POISON_FREE and POISON_INUSE.
  The old names are ambiguous.

- use the new hexdump object function in ptrinfo.

- store_stackinfo was called with wrong parameters: it should store
  caller, i.e.  __builtin_return_address(0), not POISON_AFTER in the
  object.

- dump both the object before and after the corrupted one, not just the
  one after.

Example output:
<<<
Slab corruption: start=194e708c, len=2048
Redzone: 0x5a2cf071/0x5a2cf071.
Last user: [<02399d7c>](dummy_init_module+0x1c/0xb0)
010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 7b
030: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 63
Prev obj: start=194e6880, len=2048
Redzone: 0x5a2cf071/0x5a2cf071.
Last user: [<00000000>](0x0)
000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
<<<

From: Roland McGrath <roland@redhat.com>

Under some circumstances, ptrace PEEK/POKE_TEXT can cause page permissions
to be permanently changed.  Thsi causes changes in application behaviour
when run under gdb.

Fix that by only marking the pte as writeable if the vma is marked for
writing.  A write fault thus unshares the page but doesn't necessarily make
it writeable.

Print the name of the offending slab if we're going to go BUG in
kmem_cache_init().