We say that in_atomic() is ok in the core kernel, but then always report
it regardless of where in the kernel it is.  Keep quiet if it is used in
kernel/*.
Signed-off-by: NAndy Whitcroft <apw@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I just got this new warning from kmemcheck:

    WARNING: kmemcheck: Caught 32-bit read from freed memory (c7806a60)
    a06a80c7ecde70c1a04080c700000000a06709c1000000000000000000000000
     f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f
     ^

    Pid: 0, comm: swapper Not tainted (2.6.29-rc4 #230)
    EIP: 0060:[<c1096df7>] EFLAGS: 00000286 CPU: 0
    EIP is at __purge_vmap_area_lazy+0x117/0x140
    EAX: 00070f43 EBX: c7806a40 ECX: c1677080 EDX: 00027b66
    ESI: 00002001 EDI: c170df0c EBP: c170df00 ESP: c178830c
     DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
    CR0: 80050033 CR2: c7806b14 CR3: 01775000 CR4: 00000690
    DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
    DR6: 00004000 DR7: 00000000
     [<c1096f3e>] free_unmap_vmap_area_noflush+0x6e/0x70
     [<c1096f6a>] remove_vm_area+0x2a/0x70
     [<c1097025>] __vunmap+0x45/0xe0
     [<c10970de>] vunmap+0x1e/0x30
     [<c1008ba5>] text_poke+0x95/0x150
     [<c1008ca9>] alternatives_smp_unlock+0x49/0x60
     [<c171ef47>] alternative_instructions+0x11b/0x124
     [<c171f991>] check_bugs+0xbd/0xdc
     [<c17148c5>] start_kernel+0x2ed/0x360
     [<c171409e>] __init_begin+0x9e/0xa9
     [<ffffffff>] 0xffffffff

It happened here:

    $ addr2line -e vmlinux -i c1096df7
    mm/vmalloc.c:540

Code:

	list_for_each_entry(va, &valist, purge_list)
		__free_vmap_area(va);

It's this instruction:

    mov    0x20(%ebx),%edx

Which corresponds to a dereference of va->purge_list.next:

    (gdb) p ((struct vmap_area *) 0)->purge_list.next
    Cannot access memory at address 0x20

It seems that we should use "safe" list traversal here, as the element
is freed inside the loop. Please verify that this is the right fix.
Acked-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NVegard Nossum <vegard.nossum@gmail.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The new vmap allocator can wrap the address and get confused in the case
of large allocations or VMALLOC_END near the end of address space.

Problem reported by Christoph Hellwig on a 32-bit XFS workload.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Reported-by: NChristoph Hellwig <hch@lst.de>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

free_uid() and free_user_ns() are corecursive when CONFIG_USER_SCHED=n,
but free_user_ns() is called from free_uid() by way of uid_hash_remove(),
which requires uidhash_lock to be held.  free_user_ns() then calls
free_uid() to complete the destruction.

Fix this by deferring the destruction of the user_namespace.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NHerton Ronaldo Krzesinski <herton@mandriva.com.br>
Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 4ea3ada2 declares d_obtain_alias()
as EXPORT_SYMBOL_GPL where it's supposed to replace d_alloc_anon which was
previously declared as EXPORT_SYMBOL and thus available to any loadable
module.

This patch reverts that.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The w1_ds2433 driver does not read from the hardware if the CRC was valid
on the last read.  The validcrc flag should be cleared after a write so
that the new value can be read.
Signed-off-by: NBen Gardner <gardner.ben@gmail.com>
Signed-off-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* git://git.infradead.org/mtd-2.6:
  [MTD] [MAPS] Remove MODULE_DEVICE_TABLE() from ck804rom driver.
  [JFFS2] fix mount crash caused by removed nodes
  [JFFS2] force the jffs2 GC daemon to behave a bit better
  [MTD] [MAPS] blackfin async requires complex mappings
  [MTD] [MAPS] blackfin: fix memory leak in error path
  [MTD] [MAPS] physmap: fix wrong free and del_mtd_{partition,device}
  [MTD] slram: Handle negative devlength correctly
  [MTD] map_rom has NULL erase pointer
  [MTD] [LPDDR] qinfo_probe depends on lpddr

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2:
  ocfs2: add IO error check in ocfs2_get_sector()
  ocfs2: set gap to seperate entry and value when xattr in bucket
  ocfs2: lock the metaecc process for xattr bucket
  ocfs2: Use the right access_* method in ctime update of xattr.
  ocfs2/dlm: Make dlm_assert_master_handler() kill itself instead of the asserter
  ocfs2/dlm: Use ast_lock to protect ast_list
  ocfs2: Cleanup the lockname print in dlmglue.c
  ocfs2/dlm: Retract fix for race between purge and migrate
  ocfs2: Access and dirty the buffer_head in mark_written.

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/44x: Fix address decoding setup of PCI 2.x cells

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI: AMD 813x B2 devices do not need boot interrupt quirk
  PCI: Enable PCIe AER only after checking firmware support
  PCI: pciehp: Handle interrupts that happen during initialization.
  PCI: don't enable too many HT MSI mappings
  PCI: add some sysfs ABI docs
  PCI quirk: enable MSI on 8132

The PCI 2.x cells used on some 44x SoCs only let us configure the decode
for the low 32-bit of the incoming PLB addresses. The top 4 bits (this
is a 36-bit bus) are hard wired to different values depending on the
specific SoC in use. Our code used to work "by accident" until I added
support for the ISA memory holes and while at it added more validity
checking of the addresses.

This patch should bring it back to working condition. It still relies
on the device-tree being correct but that's somewhat a pre-requisite
for anything to work anyway.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NGeert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Acked-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>

Turns out that the new AMD 813x devices do not need the
quirk_disable_amd_813x_boot_interrupt quirk to be run on them.  If it
is, no interrupts are seen on the PCI-X adapter.

From: Stefan Assmann <sassmann@novell.com>
Reported-by: NJamie Wellnitz <Jamie.Wellnitz@emulex.com>
Tested-by: NJamie Wellnitz <Jamie.Wellnitz@emulex.com>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NJesse Barnes <jbarnes@hobbes.lan>

We really don't want the BIOS flash mapping hacks to get automatically
loaded.

No idea why it isn't using pci_register_driver() though -- that should
be fine... and is even _present_ but disabled by #if 0.
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Check for IO error in ocfs2_get_sector().
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch set a gap (4 bytes) between xattr entry and
name/value when xattr in bucket. This gap use to seperate
entry and name/value when a bucket is full. It had already
been set when xattr in inode/block.
Signed-off-by: NTiger Yang <tiger.yang@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

For other metadata in ocfs2, metaecc is checked in ocfs2_read_blocks
with io_mutex held. While for xattr bucket, it is calculated by
the whole buckets. So we have to add a spin_lock to prevent multiple
processes calculating metaecc.
Signed-off-by: NTao Ma <tao.ma@oracle.com>
Tested-by: NTristan Ye <tristan.ye@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

In ctime updating of xattr, it use the wrong type of access for
inode, so use ocfs2_journal_access_di instead.
Reported-and-Tested-by: NTristan Ye <tristan.ye@oracle.com>
Signed-off-by: NTao Ma <tao.ma@oracle.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

In dlm_assert_master_handler(), if we get an incorrect assert master from a node
that, we reply with EINVAL asking the asserter to die. The problem is that an
assert is sent after so many hoops, it is invariably the node that thinks the
asserter is wrong, is actually wrong. So instead of killing the asserter, this
patch kills the assertee.

This patch papers over a race that is still being addressed.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

The code was using dlm->spinlock instead of dlm->ast_lock to protect the
ast_list. This patch fixes the issue.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

The dentry lock has a different format than other locks. This patch fixes
ocfs2_log_dlm_error() macro to make it print the dentry lock correctly.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

Mainline commit d4f7e650 attempts to delay
the dlm_thread from sending the drop ref message if the lockres is being
migrated. The problem is that we make the dlm_thread wait for the migration
to complete. This causes a deadlock as dlm_thread also participates in the
lockres migration process.

A better fix for the original oss bugzilla#1012 is in testing.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

In __ocfs2_mark_extent_written, when we meet with the situation
of c_split_covers_rec, the old solution just replace the extent
record and forget to access and dirty the buffer_head. This will
cause a problem when the unwritten extent is in an extent block.
So access and dirty it.
Signed-off-by: NTao Ma <tao.ma@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: try committing transaction before returning ENOSPC
  Btrfs: add better -ENOSPC handling

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  xen/blkfront: use blk_rq_map_sg to generate ring entries
  block: reduce stack footprint of blk_recount_segments()
  cciss: shorten 30s timeout on controller reset
  block: add documentation for register_blkdev()
  block: fix bogus gcc warning for uninitialized var usage

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc: Fix 64bit __copy_tofrom_user() regression
  powerpc: Fix 64bit memcpy() regression
  powerpc: Fix load/store float double alignment handler

It needs to happen before any firewire driver actually registers itself,
and that was previously handled by having the Makefile list the core
ieee1394 files before the drivers.

But now there are firewire drivers in drivers/media, and the Makefile
games aren't enough.  So just make ieee1394_init happen earlier in the
init sequence, the way all other bus layers already do.
Reported-and-tested-by: NIngo Molnar <mingo@elte.hu>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Henrik Kurelid <henrik@kurelid.se>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Ben Backx <ben@bbackx.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On occasion, the request will apparently have more segments than we
fit into the ring. Jens says:

> The second problem is that the block layer then appears to create one
> too many segments, but from the dump it has rq->nr_phys_segments ==
> BLKIF_MAX_SEGMENTS_PER_REQUEST. I suspect the latter is due to
> xen-blkfront not handling the merging on its own. It should check that
> the new page doesn't form part of the previous page. The
> rq_for_each_segment() iterates all single bits in the request, not dma
> segments. The "easiest" way to do this is to call blk_rq_map_sg() and
> then iterate the mapped sg list. That will give you what you are
> looking for.

> Here's a test patch, compiles but otherwise untested. I spent more
> time figuring out how to enable XEN than to code it up, so YMMV!
> Probably the sg list wants to be put inside the ring and only
> initialized on allocation, then you can get rid of the sg on stack and
> sg_init_table() loop call in the function. I'll leave that, and the
> testing, to you.

[Moved sg array into info structure, and initialize once. -J]
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

blk_recalc_rq_segments() requires a request structure passed in, which
we don't have from blk_recount_segments(). So the latter allocates one on
the stack, using > 400 bytes of stack for that. This can cause us to spill
over one page of stack from ext4 at least:

 0)     4560     400   blk_recount_segments+0x43/0x62
 1)     4160      32   bio_phys_segments+0x1c/0x24
 2)     4128      32   blk_rq_bio_prep+0x2a/0xf9
 3)     4096      32   init_request_from_bio+0xf9/0xfe
 4)     4064     112   __make_request+0x33c/0x3f6
 5)     3952     144   generic_make_request+0x2d1/0x321
 6)     3808      64   submit_bio+0xb9/0xc3
 7)     3744      48   submit_bh+0xea/0x10e
 8)     3696     368   ext4_mb_init_cache+0x257/0xa6a [ext4]
 9)     3328     288   ext4_mb_regular_allocator+0x421/0xcd9 [ext4]
10)     3040     160   ext4_mb_new_blocks+0x211/0x4b4 [ext4]
11)     2880     336   ext4_ext_get_blocks+0xb61/0xd45 [ext4]
12)     2544      96   ext4_get_blocks_wrap+0xf2/0x200 [ext4]
13)     2448      80   ext4_da_get_block_write+0x6e/0x16b [ext4]
14)     2368     352   mpage_da_map_blocks+0x7e/0x4b3 [ext4]
15)     2016     352   ext4_da_writepages+0x2ce/0x43c [ext4]
16)     1664      32   do_writepages+0x2d/0x3c
17)     1632     144   __writeback_single_inode+0x162/0x2cd
18)     1488      96   generic_sync_sb_inodes+0x1e3/0x32b
19)     1392      16   sync_sb_inodes+0xe/0x10
20)     1376      48   writeback_inodes+0x69/0xb3
21)     1328     208   balance_dirty_pages_ratelimited_nr+0x187/0x2f9
22)     1120     224   generic_file_buffered_write+0x1d4/0x2c4
23)      896     176   __generic_file_aio_write_nolock+0x35f/0x393
24)      720      80   generic_file_aio_write+0x6c/0xc8
25)      640      80   ext4_file_write+0xa9/0x137 [ext4]
26)      560     320   do_sync_write+0xf0/0x137
27)      240      48   vfs_write+0xb3/0x13c
28)      192      64   sys_write+0x4c/0x74
29)      128     128   system_call_fastpath+0x16/0x1b

Split the segment counting out into a __blk_recalc_rq_segments() helper
to avoid allocating an onstack request just for checking the physical
segment count.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

If reset_devices is set for kexec, then cciss will delay 30 seconds
since the old 5i controller _may_ need that long to recover. Replace
the long sleep with incremental sleep and tests to reduce the 30 seconds
to worst case for 5i, so that other controllers will proceed quickly.
Reviewed-by: NMike Miller <mike.miller@hp.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Add documentation for register_blkdev() function and for the parameters.
Signed-off-by: NMárton Németh <nm127@freemail.hu>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Newer gcc throw this warning:

        fs/bio.c: In function ?bio_alloc_bioset?:
        fs/bio.c:305: warning: ?p? may be used uninitialized in this function

since it cannot figure out that 'p' is only ever used if 'bs' is non-NULL.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This fixes a regression introduced by commit
a4e22f02 ("powerpc: Update 64bit
__copy_tofrom_user() using CPU_FTR_UNALIGNED_LD_STD").

The same bug that existed in the 64bit memcpy() also exists here so fix
it here too. The fix is the same as that applied to memcpy() with the
addition of fixes for the exception handling code required for
__copy_tofrom_user().

This stops us reading beyond the end of the source region we were told
to copy.
Signed-off-by: NMark Nelson <markn@au1.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This fixes a regression introduced by commit
25d6e2d7 ("powerpc: Update 64bit memcpy()
using CPU_FTR_UNALIGNED_LD_STD").

This commit allowed CPUs that have the CPU_FTR_UNALIGNED_LD_STD CPU
feature bit present to do the memcpy() with unaligned load doubles. But,
along with this came a bug where our final load double would read bytes
beyond a page boundary and into the next (unmapped) page. This was caught
by enabling CONFIG_DEBUG_PAGEALLOC,

The fix was to read only the number of bytes that we need to store rather
than reading a full 8-byte doubleword and storing only a portion of that.

In order to minimise the amount of existing code touched we use the
original do_tail for the src_unaligned case.

Below is an example of the regression, as reported by Sachin Sant:

Unable to handle kernel paging request for data at address 0xc00000003f380000
Faulting instruction address: 0xc000000000039574
cpu 0x1: Vector: 300 (Data Access) at [c00000003baf3020]
    pc: c000000000039574: .memcpy+0x74/0x244
    lr: d00000000244916c: .ext3_xattr_get+0x288/0x2f4 [ext3]
    sp: c00000003baf32a0
   msr: 8000000000009032
   dar: c00000003f380000
 dsisr: 40000000
  current = 0xc00000003e54b010
  paca    = 0xc000000000a53680
    pid   = 1840, comm = readahead
enter ? for help
[link register   ] d00000000244916c .ext3_xattr_get+0x288/0x2f4 [ext3]
[c00000003baf32a0] d000000002449104 .ext3_xattr_get+0x220/0x2f4 [ext3]
(unreliab
le)
[c00000003baf3390] d00000000244a6e8 .ext3_xattr_security_get+0x40/0x5c [ext3]
[c00000003baf3400] c000000000148154 .generic_getxattr+0x74/0x9c
[c00000003baf34a0] c000000000333400 .inode_doinit_with_dentry+0x1c4/0x678
[c00000003baf3560] c00000000032c6b0 .security_d_instantiate+0x50/0x68
[c00000003baf35e0] c00000000013c818 .d_instantiate+0x78/0x9c
[c00000003baf3680] c00000000013ced0 .d_splice_alias+0xf0/0x120
[c00000003baf3720] d00000000243e05c .ext3_lookup+0xec/0x134 [ext3]
[c00000003baf37c0] c000000000131e74 .do_lookup+0x110/0x260
[c00000003baf3880] c000000000134ed0 .__link_path_walk+0xa98/0x1010
[c00000003baf3970] c0000000001354a0 .path_walk+0x58/0xc4
[c00000003baf3a20] c000000000135720 .do_path_lookup+0x138/0x1e4
[c00000003baf3ad0] c00000000013645c .path_lookup_open+0x6c/0xc8
[c00000003baf3b70] c000000000136780 .do_filp_open+0xcc/0x874
[c00000003baf3d10] c0000000001251e0 .do_sys_open+0x80/0x140
[c00000003baf3dc0] c00000000016aaec .compat_sys_open+0x24/0x38
[c00000003baf3e30] c00000000000855c syscall_exit+0x0/0x40
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

When we introduced VSX, we changed the way FPRs are stored in the
thread_struct.  Unfortunately we missed the load/store float double
alignment handler code when updating how we access FPRs in the
thread_struct.

Below fixes this and merges the little/big endian case.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
  ALSA: emu10k1 - Fix digital/analog switch on audigy2 ZS
  ALSA: hda - Quirk for Acer Aspire 6530G
  ALSA: hda - add another MacBook Pro 3,1 SSID
  ALSA: fix excessive background noise introduced by OSS emulation rate shrink
  ALSA: aw2: do not grab every saa7146 based device
  ALSA: hda - Fix parse of init_verbs sysfs entry
  ALSA: pcxhr.h replace signed one-bit bitfields

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
  [IA64] Don't go beyond iosapic_intr_info's arraysize
  [IA64] Do not go beyond ARRAY_SIZE of unw.hash
  [IA64] enable setting DMAR on by default

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  [libata] pata_legacy: for VLB 32bit PIO don't try tricks with slop
  [libata] pata_amd: program FIFO
  sata_mv: fix SoC interrupt breakage
  pata_it821x: resume from hibernation fails with RAID volume

These devices are generally used with ATA anyway and it seems that some
ATAPI will need us to issue the right number of words.  Therefore as we
can't switch mid burst on VLB devices we should only use 32bit I/O for
suitable block sizes.
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

With 32bit PIO we can use the posted write buffers, but only for 32bit I/O
cycles.  This means we must disable the FIFO for ATAPI where a final 16bit
cycle may occur.

Rework the FIFO logic so that we disable the FIFO then selectively
re-enable it when we set the timings on AMD devices.  Also fix a case
where we scribbled on PCI config 0x41 of Nvidia chips when we shouldn't.
Signed-off-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>