linux-toradex.git/include/linux, branch v2.6.33.5

revert "procfs: provide stack information for threads" and its fixup commits

2010-05-26T21:32:04+00:00

commit 34441427aab4bdb3069a4ffcda69a99357abcb2e upstream.

Originally, commit d899bf7b ("procfs: provide stack information for
threads") attempted to introduce a new feature for showing where the
threadstack was located and how many pages are being utilized by the
stack.

Commit c44972f1 ("procfs: disable per-task stack usage on NOMMU") was
applied to fix the NO_MMU case.

Commit 89240ba0 ("x86, fs: Fix x86 procfs stack information for threads on
64-bit") was applied to fix a bug in ia32 executables being loaded.

Commit 9ebd4eba7 ("procfs: fix /proc//stat stack pointer for kernel
threads") was applied to fix a bug which had kernel threads printing a
userland stack address.

Commit 1306d603f ('proc: partially revert "procfs: provide stack
information for threads"') was then applied to revert the stack pages
being used to solve a significant performance regression.

This patch nearly undoes the effect of all these patches.

The reason for reverting these is it provides an unusable value in
field 28.  For x86_64, a fork will result in the task->stack_start
value being updated to the current user top of stack and not the stack
start address.  This unpredictability of the stack_start value makes
it worthless.  That includes the intended use of showing how much stack
space a thread has.

Other architectures will get different values.  As an example, ia64
gets 0.  The do_fork() and copy_process() functions appear to treat the
stack_start and stack_size parameters as architecture specific.

I only partially reverted c44972f1 ("procfs: disable per-task stack usage
on NOMMU") .  If I had completely reverted it, I would have had to change
mm/Makefile only build pagewalk.o when CONFIG_PROC_PAGE_MONITOR is
configured.  Since I could not test the builds without significant effort,
I decided to not change mm/Makefile.

I only partially reverted 89240ba0 ("x86, fs: Fix x86 procfs stack
information for threads on 64-bit") .  I left the KSTK_ESP() change in
place as that seemed worthwhile.

Signed-off-by: Robin Holt 
Cc: Stefani Seibold 
Cc: KOSAKI Motohiro 
Cc: Michal Simek 
Cc: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

libata: Fix accesses at LBA28 boundary (old bug, but nasty) (v2)

2010-05-12T22:02:49+00:00

commit 45c4d015a92f72ec47acd0c7557abdc0c8a6499d upstream.

Most drives from Seagate, Hitachi, and possibly other brands,
do not allow LBA28 access to sector number 0x0fffffff (2^28 - 1).
So instead use LBA48 for such accesses.

This bug could bite a lot of systems, especially when the user has
taken care to align partitions to 4KB boundaries. On misaligned systems,
it is less likely to be encountered, since a 4KB read would end at
0x10000000 rather than at 0x0fffffff.

Signed-off-by: Mark Lord 
Signed-off-by: Jeff Garzik 
Signed-off-by: Greg Kroah-Hartman

hugetlb: fix infinite loop in get_futex_key() when backed by huge pages

2010-05-12T22:02:33+00:00

commit 23be7468e8802a2ac1de6ee3eecb3ec7f14dc703 upstream.

If a futex key happens to be located within a huge page mapped
MAP_PRIVATE, get_futex_key() can go into an infinite loop waiting for a
page->mapping that will never exist.

See https://bugzilla.redhat.com/show_bug.cgi?id=552257 for more details
about the problem.

This patch makes page->mapping a poisoned value that includes
PAGE_MAPPING_ANON mapped MAP_PRIVATE.  This is enough for futex to
continue but because of PAGE_MAPPING_ANON, the poisoned value is not
dereferenced or used by futex.  No other part of the VM should be
dereferencing the page->mapping of a hugetlbfs page as its page cache is
not on the LRU.

This patch fixes the problem with the test case described in the bugzilla.

[akpm@linux-foundation.org: mel cant spel]
Signed-off-by: Mel Gorman 
Acked-by: Peter Zijlstra 
Acked-by: Darren Hart 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

KVM: Increase NR_IOBUS_DEVS limit to 200

2010-04-26T14:48:05+00:00

(Cherry-picked from commit e80e2a60ff7914dae691345a976c80bbbff3ec74)

This patch increases the current hardcoded limit of NR_IOBUS_DEVS
from 6 to 200. We are hitting this limit when creating a guest with more
than 1 virtio-net device using vhost-net backend. Each virtio-net
device requires 2 such devices to service notifications from rx/tx queues.

Signed-off-by: Sridhar Samudrala 
Signed-off-by: Avi Kivity 
Signed-off-by: Greg Kroah-Hartman

KVM: fix the handling of dirty bitmaps to avoid overflows

2010-04-26T14:48:05+00:00

(Cherry-picked from commit 87bf6e7de1134f48681fd2ce4b7c1ec45458cb6d)

Int is not long enough to store the size of a dirty bitmap.

This patch fixes this problem with the introduction of a wrapper
function to calculate the sizes of dirty bitmaps.

Note: in mark_page_dirty(), we have to consider the fact that
  __set_bit() takes the offset as int, not long.

Signed-off-by: Takuya Yoshikawa 
Signed-off-by: Marcelo Tosatti 
Signed-off-by: Greg Kroah-Hartman

module: fix __module_ref_addr()

2010-04-26T14:48:03+00:00

The __module_ref_addr() problem disappears in 2.6.34-rc kernels because these
percpu accesses were re-factored.

__module_ref_addr() should use per_cpu_ptr() to obfuscate the pointer
(RELOC_HIDE is needed for per cpu pointers).

This non-standard per-cpu pointer use has been introduced by commit
720eba31f47aeade8ec130ca7f4353223c49170f

It causes a NULL pointer exception on some configurations when CONFIG_TRACING is
enabled on 2.6.33. This patch fixes the problem (acknowledged by Randy who
reported the bug).

It did not appear to hurt previously because most of the accesses were done
through local_inc, which probably obfuscated the access enough that no compiler
optimizations were done. But with local_read() done when CONFIG_TRACING is
active, this becomes a problem. Non-CONFIG_TRACING is probably affected as well
(module.c contains local_set and local_read that use __module_ref_addr()), but I
guess nobody noticed because we've been lucky enough that the compiler did not
generate the inappropriate optimization pattern there.

This patch should be queued for the 2.6.29.x through 2.6.33.x stable branches.
(tested on 2.6.33.1 x86_64)

Signed-off-by: Mathieu Desnoyers 
Tested-by: Randy Dunlap 
CC: Eric Dumazet 
CC: Rusty Russell 
CC: Peter Zijlstra 
CC: Tejun Heo 
CC: Ingo Molnar 
CC: Andrew Morton 
CC: Linus Torvalds 
CC: Greg Kroah-Hartman 
CC: Steven Rostedt 
Signed-off-by: Greg Kroah-Hartman

x86/PCI: irq and pci_ids patch for Intel Cougar Point DeviceIDs

2010-04-26T14:48:00+00:00

commit 93da6202264ce1256b04db8008a43882ae62d060 upstream.

This patch adds the Intel Cougar Point (PCH) LPC and SMBus Controller DeviceIDs.

Signed-off-by: Seth Heasley 
Signed-off-by: Jesse Barnes 
Cc: maximilian attems 
Signed-off-by: Greg Kroah-Hartman

pci: Update pci_set_vga_state() to call arch functions

2010-04-26T14:47:59+00:00

commit 95a8b6efc5d07103583f706c8a5889437d537939 upstream.

Update pci_set_vga_state to call arch dependent functions to enable Legacy
VGA I/O transactions to be redirected to correct target.

[akpm@linux-foundation.org: make pci_register_set_vga_state() __init]
Signed-off-by: Mike Travis 
LKML-Reference: <201002022238.o12McE1J018723@imap1.linux-foundation.org>
Cc: Thomas Gleixner 
Cc: Robin Holt 
Cc: Jack Steiner 
Cc: Ingo Molnar 
Cc: Jesse Barnes 
Cc: David Airlie 
Signed-off-by: Andrew Morton 
Signed-off-by: H. Peter Anvin 
Cc: maximilian attems 
Signed-off-by: Greg Kroah-Hartman

dm ioctl: introduce flag indicating uevent was generated

2010-04-26T14:47:57+00:00

commit 3abf85b5b5851b5f28d3d8a920ebb844edd08352 upstream.

Set a new DM_UEVENT_GENERATED_FLAG when returning from ioctls to
indicate that a uevent was actually generated.  This tells the userspace
caller that it may need to wait for the event to be processed.

Signed-off-by: Peter Rajnoha 
Signed-off-by: Alasdair G Kergon 
Signed-off-by: Greg Kroah-Hartman

NFSv4: fix delegated locking

2010-04-26T14:47:53+00:00

commit 0df5dd4aae211edeeeb84f7f84f6d093406d7c22 upstream.

Arnaud Giersch reports that NFSv4 locking is broken when we hold a
delegation since commit 8e469ebd6dc32cbaf620e134d79f740bf0ebab79 (NFSv4:
Don't allow posix locking against servers that don't support it).

According to Arnaud, the lock succeeds the first time he opens the file
(since we cannot do a delegated open) but then fails after we start using
delegated opens.

The following patch fixes it by ensuring that locking behaviour is
governed by a per-filesystem capability flag that is initially set, but
gets cleared if the server ever returns an OPEN without the
NFS4_OPEN_RESULT_LOCKTYPE_POSIX flag being set.

Reported-by: Arnaud Giersch 
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman