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().

Fairly pointless coding-style cleanups which I've been sitting on for ages.
The ramdisk driver is still buggy: it drops pagecache when unmounted.  I
still need to fix this.

Apparently it also displays data corruption under load even when not
unmounted.

Correct the cache setup bits for the 5407. This enables the write
buffers properly (despite what the previous comment said). This
combined with fixed cache flushing code provides a nice performance
boost on the 5407.

Also fix the ROMfs setup to only move the ROMfs region if it is actually
configured.

Added ELF relocation type defines.  These are needed by the module
loading code for m68knommu.

This adds the configuration option to enable the uClinux shared flat
binary support.  The code support is already in the binfmt_load code,
just the config option is missing.

Fix a number of memory leaks in the uClinux binfmt_flat loader.  All are
related to not cleaning up properly on failure conditions.

From: Janet Morgan <janetmor@us.ibm.com>

It looks like aio_nr and aio_max_nr were intended to be sysctl parameters.

From: Christoph Hellwig <hch@lst.de>

I've just grepped over the tree for reamining MOD_INC_USE_COUNT users, and
ftape is a really horrible one, it relies on MOD_{INC,DEV}_USE_COUNT in the
most horrible places + it's own bookkepping and the <= 2.4 may unload
hooks.  And although I don't have the hardware I can guarantee it doesn't
work as expected.

So let's just remove the module_exit handler and mark it unremovable, if
someone wants to fix up ftape later it's fine with me, but it's a really
scary driver..

From: "Art Haas" <ahaas@airmail.net>

Here's a small patch that adds C99 initializers to the file.

From: Matt Domsch <Matt_Domsch@dell.com>

Patch below applies to both 2.4.25 and 2.6.3, and replaces the public
domain statement and non-warranty with the GPL, as is permitted by the code
being in the public domain, and is done with legal advice.

From: Gerd Knorr <kraxel@bytesex.org>

"options tuner type=2" is just there for historical reasons and should
only be used/needed if the main driver doesn't allow to configure the
tuner type.  I'm not sure whenever I can remove that altogether without
breaking anything.  There are several users of the tuner module, some
outside the standard kernel tree ...

> >         if (type < TUNERS) {
> > +               t->type = type;
> >                 printk("tuner: type forced to %d (%s) [insmod]\n",
> >                        t->type,tuners[t->type].name);
> >                 set_type(client,type);

That is wrong, it will break in other corner cases, it may cause the
set_type() function not doing the initializations.

The prink can also be dropped because set_type does that too.  The patch
below removes that.  It also makes the kernel messages a bit more verbose
and adds support for two new tuners.

From: mcgrof@studorgs.rutgers.edu (Luis R. Rodriguez)

Complete the migration from Kconfig's undocumented "enable" to "select".

From: Pragnesh Sampat <pragnesh.sampat@timesys.com>

The file initramfs_data.cpio is slightly different when generated on
cygwin, compared to linux, which causes the kernel to panic with the
message "no cpio magic" (See Documentation/early-userspace/README).

The problem in cpio generation is due to the difference in sprintf
modifiers on cygwin.  The code uses "%08ZX" for strlen of a device node.
printf man pages discourages "Z" and has 'z' instead.  Both of these are
not available on cygwin sprintf (at least some versions of cygwin).  The
net result of all of this is that the generated file literally contains
"ZX" and then the strlen after that and messes up that 110 offset etc.  The
file is 516 bytes long on the system that I tested and on linux it is 512
bytes.

The fix below just uses "%08X" for that field.

From: Urban Widmark <urban@teststation.com>

Add the necessary bits for loop-over-smbfs.

From: Michael Frank <mhf@linuxmail.org>

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

There's no real need to BUG and stop the system from booting if the BIOS
spec'ed apicid for the boot CPU isn't correct - we can continue perfectly
well with the real one.

From: "ZIGLIO, Frediano, VF-IT" <Frediano.Ziglio@vodafone.com>

Add a new driver for the SF16FMR2 Radio card.

From: Martin Hicks <mort@wildopensource.com>

This is a patch based on one that Jack Steiner sent to the ia64 list in
November.  The original thread can be found at:

http://marc.theaimsgroup.com/?l=linux-ia64&m=106869606922555&w=2

I created the little wrapper function that was requested.  I think the only
other arch, other than ia64, that doesn't at least include asm-generic/tlb.h
is arm.


Something appears broken in TLB flushing on IA64 (& possibly other
architectures).  Functionally, it works but performance is bad on systems
with large cpu counts.

The result is that TLB flushing in exit_mmap() is frequently being done via
IPIs to all cpus rather than with a "ptc" instruction or with a new
context..

From: Sam Ravnborg <sam@ravnborg.org>

Corrected check for missing ncurses-devel when executing "make menuconfig".
Now tell user to install 'ncurses-devel' if check fails.

From: Thomas Davis <tadavis@lbl.gov>

Doing a 'make rpm' will fail with the current RH9/Fedora RPM macros.

The failure message is this:

Processing files: kernel-debuginfo-2.6.3rc1mm1-12
error: Could not open %files file /usr/src/redhat/BUILD/kernel-2.6.3rc1mm1/debugfiles.list: No such file or directory

The fix is this patch:

From: Christophe Saout <christophe@saout.de>

Adds a crypto module for device-mapper.  The intent here is to remove
cryptoloop ASAP, to pull the remapping gunk out of the loops driver and to
migrate people onto dm-crypt.  It is on-disk compatible with existing
cryptolop installations.

See http://www.saout.de/misc/dm-crypt/ for usage details.

From: Andi Kleen <ak@suse.de>

Make the "hm, page reserved twice" message dependent on CONFIG_DEBUG_BOOTMEM.

From: Willem Riede <wrlk@riede.org>


The onstream drives, be they scsi, atapi, ieee1394 or usb, are supported by the
osst driver.  When the drives were new, code was introduced in ide-tape
independently, but never really maintained since.  There are issues with the
drives I found and dealt with in osst, that ide-tape doesn't address.

So this code in ide-tape is both redundant and imperfect.  I assumed from
http://marc.theaimsgroup.com/?l=linux-kernel&m=107550547613846&w=2 that there
was buy in for removing it.

When this patch is applied, ide-tape will refuse to attach to an onstream DI
drive, and will write to syslog to use ide-scsi + osst instead.

From: BlaisorBlade <blaisorblade_spam@yahoo.it>

An exhausted do_swap_page() should return VM_FAULT_OOM rather than -ENOMEM.

From: "David S. Miller" <davem@redhat.com>

From: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

If I create some kmem cache on 64-bit with like 3 u32's in it, it should
silently just work and not warn.

From: Davide Libenzi <davidel@xmailserver.org>

A potential race can happen in epoll_ctl(EPOLL_CTL_MOD) where an event can
happen in between f_op->poll() and the lock on ep->lock (we cannot call
f_op->poll() inside a lock, and the f_op->poll() callback does not carry
any info at the current time - missing wake_up_info() already ;).  In that
case the event would be removed.  We can easily leave the event inside the
ready list and have the ep_send_events() logic do the job for us at later
time.  (Thanks to david.lee@teracruz.com for reporting the thing, since it
shouldn't have been a nice one ;)

From: Anton Blanchard <anton@samba.org>

Add clock_was_set to all architectures.  I'm disappointed this wasnt done by
whoever wrote the code.

(It is a callback which the arch-specific RTC-updating code must make when
someone sets the time).

From: Brian Gerst <bgerst@didntduck.org>

Cleans up some leftovers from the old module loader:

- Remove unused defines from modules.h

- Remove unused file modsetver.h

From: Alex Goddard <agoddard@purdue.edu>

How to debug module loading problems.  The wording is a slightly changed
version of what Rusty said.

From: MAEDA Naoaki <maeda.naoaki@jp.fujitsu.com>

I am testing PCI hot-plug in 2.6.2 kernel, but sometimes a struct resource
tree in kernel/resource.c was broken if multiple hot-plug requests are
issued at the same time.

The reason is lots of drivers call release_region() on hot removal, and
__release_region(), which is invoked by release_region() macro, changes the
tree without holding a writer lock for resource_lock.

I think __release_region() must hold a writer lock as well as
__request_region() does.

A following patch fixes the issue in my environment.

From: Tim Hockin <thockin@sun.com>

Remove the max_anon via dynamically allocation.  We also change the
idr_pre_get() interface to take a gfp mask, which should have always been
there.

From: Philippe Elie <phil.el@wanadoo.fr>

From: Will Cohen <wcohen@redhat.com>

Add oprofile support for Pentium Mobile (P6 core).  Pentium Mobile needs to
unmask LVPTC vector, since it doesn't hurt other P6 core based cpus we do
it unconditionally for all these.

This patch require userspace tools >= 0.8 (only in sourceforge cvs currently)

From: Philippe Elie <phil.el@wanadoo.fr>

From: Zwane Mwaikambo <zwane@arm.linux.org.uk>

This patch adds infrastructure code and enables ARM to utilise the timer
int oprofile driver.  There is PMU code under development for the XScale
but that is still forthcoming.  In the meantime you can use the timer int
driver with an updated Oprofile-CVS userspace (SF is a bit slow, please
allow 24hrs).

From: Philippe Elie <phil.el@wanadoo.fr>

From: Zwane Mwaikambo <zwane@arm.linux.org.uk>

The nmi_timer_int oprofile driver was enabling itself unconditionally if an
SMP kernel was being used on a UP system without an IOAPIC.

Tested on a P5 using NMI timer int driver and UP system using timer int
driver both running an SMP kernel.

2004-02-11  Zwane Mwaikambo <zwane@arm.linux.org.uk>

	* arch/i386/kernel/nmi.c: export nmi_active
	* arch/i386/oprofile/nmi_timer_int.c: use it to check if owe can use
	  an nmi interrupt

Some machines appear to have BIOS problems which are causing 3c59x adapters
to come up in a powered-off state when WOL and PM are enabled.

So bring back the 2.4 `enable_wol' module option which disables wake-on-lan
unless the user specifically asked for it.