Patch from: Joel Becker <Joel.Becker@oracle.com>

This kernel module will detect long durations when jiffies has failed to
increment, and will reboot the machine in response.

Joel says:


"Here's why Oracle wants such a thing.  We run clusters.  Imagine a two node
 cluster.  Node1 pauses completely for some reason.  There are multiple
 reasons this can happen.  A bad driver can udelay() for 90 seconds (qla used
 to do this).  zVM on S/390 can page Linux out for minutes at a time.
 Anything that causes the box to freeze.  Jiffies does *not* count during
 this, so when Node1 returns it feels that no time has passed.

 Node2, however, has been counting time.  When Node1 goes away, the Oracle
 cluster manager starts looking for it.  After a timeout, it gives up.  It
 then recovers any in-progress transactions from Node1.  After that, it
 starts new operations, modifying the data in ways that Node1 has no idea
 about (it's still out to lunch).

 When Node1 finally returns (udelay() ends, zVM pages it in, whatever), any
 I/O that it has queued or is about to queue will get sent to the disk.
 Oops, you've just corrupted your shared data.

 hangcheck-timer should catch this and reboot the box.

 This is why Oracle wants this driver.  We figure that such functionality
 would be beneficial to others as well, so we posted to l-k.  We'd all hope
 that driver writers don't udelay() for 90s, but S/390 with zVM is still
 around.  Some folks might want to notice when it happens.  I am sure other
 things exist that trigger the same symptoms."

Lots of nonsensical locking in there.

Patch from Manfred Spraul <manfred@colorfullife.com>

When slab debugging is enabled we're holding off interrupts for too long
(more than a jiffy), so reduce the alloc/free batching size when slab debug
is enabled.

From wli

A moment's reflection on the subject suggests to me it's worthwhile to
generalize pgd_ctor support so it works (without #ifdefs!) on both PAE
and non-PAE. This tiny tweak is actually more noticeably beneficial
on non-PAE systems but only really because pgd_alloc() is more visible;
the most likely reason it's less visible on PAE is "other overhead".
It looks particularly nice since it removes more code than it adds.

Touch tested on NUMA-Q (PAE). OFTC #kn testers testing the non-PAE case.

From Bill Irwin

This allocates pgd's and pmd's using the slab and slab ctors.  It has a
benefit beyond preconstruction in that PAE pmd's are accounted via
/proc/slabinfo

Profiling of kernel builds by Martin Bligh shows a 30-40% drop in CPU load
due to pgd_alloc()'s page clearing activity.  But this was already a tiny
fraction of the overall CPU time.

Patch From: Hugh Dickins <hugh@veritas.com>

Recently noticed that __GFP_HIGHIO has played no real part since bounce
buffering was converted to mempool in 2.5.12: so this patch (over 2.5.58-mm1)
removes it and GFP_NOHIGHIO and SLAB_NOHIGHIO.

Also removes GFP_KSWAPD, in 2.5 same as GFP_KERNEL; leaves GFP_USER, which
can be a useful comment, even though in 2.5 same as GFP_KERNEL.

One anomaly needs comment: strictly, if there's no __GFP_HIGHIO, then
GFP_NOHIGHIO translates to GFP_NOFS; but GFP_NOFS looks wrong in the block
layer, and if you follow them down, you find that GFP_NOFS and GFP_NOIO
behave the same way in mempool_alloc - so I've used the less surprising
GFP_NOIO to replace GFP_NOHIGHIO.

Patch from Nikita Danilov <Nikita@Namesys.COM>

read_cache_pages() is passed a bunch of pages to start I/O against and it is
supposed to consume all those pages.  But if there is an I/O error, someone
need to throw away the unused pages.

At present the single user of read_cache_pages() (nfs_readpages) does that
cleanup by hand.  But it should be done in the core kernel.

- Don't require a 160-col xterm

- Coding style consistency

Implements merging of file-backed VMA's.  Based on Andrea's 2.4 patch.

It's only done for mmap().  mprotect() and mremap() still will not merge
VMA's.

It works for hugetlbfs mappings also.

pagecache can be reclaimed via the page LRU and via prune_icache.  We
currently don't know how much reclaim is happening via each.

The patch adds instrumentation to display the number of pages which were
freed via prune_icache.  This is displayed in /proc/vmstat:pginodesteal and
/proc/vmstat:kswapd_inodesteal.

Turns out that under some workloads (well, dbench at least), fully half of
page reclaim is via the unused inode list.  Which seems quite OK to me.

A static function in a header where presumably a static inline was intended.

An implementation of posix_fadvise64().  It adds 368 bytes to my vmlinux and
is worth it.

I didn't bother doing posix_fadvise(), as userspace can implement that by
calling fadvise64().

The main reason for wanting this syscall is to provide userspace with the
ability to explicitly shoot down pagecache when streaming large files.  This
is what O_STEAMING does, only posix_fadvise() is standards-based, and harder
to use.

posix_fadvise() also subsumes sys_readahead().

POSIX_FADV_WILLNEED will generally provide asynchronous readahead semantics
for small amounts of I/O.  As long as things like indirect blocks are aready
in core.

POSIX_FADV_RANDOM gives unprivileged applications a way of disabling
readahead on a per-fd basis, which may provide some benefit for super-seeky
access patterns such as databases.



The POSIX_FADV_* values are already implemented in glibc, and this patch
ensures that they are in sync.

A test app (fadvise.c) is available in ext3 CVS.  See

	http://www.zip.com.au/~akpm/linux/ext3/

for CVS details.

Ulrich has reviewed this patch (thanks).

into penguin.transmeta.com:/home/penguin/torvalds/repositories/kernel/linux

One of the goals of the whole new modversions implementation:
export-objs is gone for good!

into shaggy.austin.ibm.com:/shaggy/bk/jfs-2.5

o Build modules with CONFIG_MODVERSIONS when just saying "make"
o Ignore generated *.ver.c files
o Fix a typo (Sam Ravnborg)
o Fix another typo (Paul Marinceu)

into tp1.ruhr-uni-bochum.de:/scratch/kai/kernel/v2.5/linux-2.5.make

Skip over the first part of __vermagic in modversioning is on: otherwise
you'll have to force it when changing from 2.6.0 to 2.6.1.

Fix the case where no CRCs are supplied (OK, but taints kernel), and
only print one tainted message (otherwise --force gives hundreds of them).

We generated the intermediate files that contain checksums for
unresolved symbols in .tmp_versions, which had the disadvantage
that is obscured what's going on during the build. Just
generate them as .ver.[co] right next to the actual objects in the
object tree.

CONFIG_MODVERSIONING was a temporary name introduced to distinguish
between the old and new module version implementation. Since the
traces of the old implementation are now gone from the build system,
we rename the config option back in order to not confuse users more
than necessary in 2.6.
 
Also, remove some historic modversions cruft throughout the tree.

into hostme.bitkeeper.com:/ua/repos/j/jfs/linux-2.5

After disabling files that wouldn't build, there were 2 (in-kernel)
modules that referenced _init or _exit code sections when they
shouldn't.

This fixes those modules.

into home.transmeta.com:/home/torvalds/v2.5/linux

into raven.il.steeleye.com:/home/jejb/BK/scsi-for-linus-2.5

into raven.il.steeleye.com:/home/jejb/BK/scsi-for-linus-2.5

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

into home.transmeta.com:/home/torvalds/v2.5/linux

Certain support files are shared between various ARM machine classes.
In other to sanely support these, we place the shared files in
arch/arm/common instead of the individual machine class directories.

Patch from Russell King <rmk@arm.linux.org.uk>

show_task() attempts to calculate the amount of free space which hasn't been
written to on the kernel stack by reading from the base of the kernel stack
upwards.

However, it mistakenly uses the task_struct pointer as the base of the stack,
which it isn't, and this can cause an oops.

Here is a patch which uses the task thread pointer instead, which should be
located at the bottom of the kernel stack.  It appears this was missed when
the thread structure was introduced.

The recent exit_mmap() changes broke PPC64 when 64-bit applications exec
32-bit ones.  ia32-on-ia64 was broken as well

What is happening is that load_elf_binary() sets TIF_32BIT (via
SET_PERSONALITY) _before_ running exit_mmap().  So when we're unmapping the
vma's of the old image, we are running under the new image's personality.

This causes PPC64 to pass a 32-bit TASK_SIZE to unmap_vmas(), even when the
execing process had a 64-bit image.  Because unmap_vmas() is not provided
with the correct virtual address span it does not unmap all the old image's
vma's and we go BUG_ON(mm->map_count) in exit_mmap().

The early SET_PERSONALITY() is required before we look up the interpreter
because the lookup of the executable has to happen under the alternate root
which SET_PERSONALITY() may set.

Unfortunately this means that we're running flush_old_exec() under the new
exec's personality.  Hence this bug.

So what the patch does is to simply pass ~0UL into unmap_vmas(), which tells
it to unmap everything regardless of current personality.  Which is what the
old open-coded VMA killer was doing.

There remains the problem that some architectures are sometimes passing the
incorrect TASK_SIZE into tlb_finish_mmu().  They've always been doing that.

We cannot clear VM_MAYWRITE in there - it turns writeable MAP_PRIVATE
mappings into readonly ones.

So change it back to the 2.4 form - disallow a writeable MAP_SHARED mapping
against filesystems which do not implement ->writepage().

Patch from: Petr Vandrovec <vandrove@vc.cvut.cz>

soundcore is trying to perform kernel syscalls to load firmware, but falls
afoul of missing `errno'.  Convert it to use VFS API functions.

redo_fd_request() needs to take the queue lock around the call to
elv_next_request().

Patch from "Andres Salomon" <dilinger@voxel.net>

Fix compilation of atyfb_base.c

__wait_on_buffer() needs to use io_schedule(), so processes in there are
accounted as being in I/O wait.