If user space attempts to remove a non-existent file or directory, and
the file system is mounted read-only, return ENOENT instead of EROFS.
Either error code is arguably valid/correct, but ENOENT is a more
specific error message.

Reported-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Callers of lmLogOpen() expect it to return -E... on failure exits, which
is what it returns, except for the case of blkdev_get_by_dev() failure.
It that case lmLogOpen() return the error with the wrong sign...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>

Commit 64252c75

 removed the useless dget from dentry_unhash but didn't
fix up this caller in the usb code.  There used to be exactly one dput per
dentry_unhash call; now there are none.

Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Caching "we have already removed suid/caps" was overenthusiastic as merged.
On network filesystems we might have had suid/caps set on another client,
silently picked by this client on revalidate, all of that *without* clearing
the S_NOSEC flag.

AFAICS, the only reasonably sane way to deal with that is
	* new superblock flag; unless set, S_NOSEC is not going to be set.
	* local block filesystems set it in their ->mount() (more accurately,
mount_bdev() does, so does btrfs ->mount(), users of mount_bdev() other than
local block ones clear it)
	* if any network filesystem (or a cluster one) wants to use S_NOSEC,
it'll need to set MS_NOSEC in sb->s_flags *AND* take care to clear S_NOSEC when
inode attribute changes are picked from other clients.

It's not an earth-shattering hole (anybody that can set suid on another client
will almost certainly be able to write to the file before doing that anyway),
but it's a bug that needs fixing.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

This reverts commit a197b59a.

As rmk says:
 "Commit a197b59a

 (mm: fail GFP_DMA allocations when ZONE_DMA is not
  configured) is causing regressions on ARM with various drivers which
  use GFP_DMA.

  The behaviour up until now has been to silently ignore that flag when
  CONFIG_ZONE_DMA is not enabled, and to allocate from the normal zone.
  However, as a result of the above commit, such allocations now fail
  which causes drivers to fail.  These are regressions compared to the
  previous kernel version."

so just revert it.

Requested-by: Russell King <linux@arm.linux.org.uk>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* git://git.infradead.org/iommu-2.6:
  intel-iommu: Fix off-by-one in RMRR setup
  intel-iommu: Add domain check in domain_remove_one_dev_info
  intel-iommu: Remove Host Bridge devices from identity mapping
  intel-iommu: Use coherent DMA mask when requested
  intel-iommu: Dont cache iova above 32bit
  intel-iommu: Speed up processing of the identity_mapping function
  intel-iommu: Check for identity mapping candidate using system dma mask
  intel-iommu: Only unlink device domains from iommu
  intel-iommu: Enable super page (2MiB, 1GiB, etc.) support
  intel-iommu: Flush unmaps at domain_exit
  intel-iommu: Remove obsolete comment from detect_intel_iommu
  intel-iommu: fix VT-d PMR disable for TXT on S3 resume

Jens' back-merge commit 698567f3 ("Merge commit 'v2.6.39' into
for-2.6.40/core") was incorrectly done, and re-introduced the
DISK_EVENT_MEDIA_CHANGE lines that had been removed earlier in commits

 - 9fd097b1 ("block: unexport DISK_EVENT_MEDIA_CHANGE for
   legacy/fringe drivers")

 - 7eec77a1 ("ide: unexport DISK_EVENT_MEDIA_CHANGE for ide-gd
   and ide-cd")

because of conflicts with the "g->flags" updates near-by by commit
d4dc210f

 ("block: don't block events on excl write for non-optical
devices")

As a result, we re-introduced the hanging behavior due to infinite disk
media change reports.

Tssk, tssk, people! Don't do back-merges at all, and *definitely* don't
do them to hide merge conflicts from me - especially as I'm likely
better at merging them than you are, since I do so many merges.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* git://git.infradead.org/mtd-2.6:
  mtd: fix physmap.h warnings

We were mapping an extra byte (and hence usually an extra page):
iommu_prepare_identity_map() expects to be given an 'end' argument which
is the last byte to be mapped; not the first byte *not* to be mapped.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The comment in domain_remove_one_dev_info() states "No need to compare
PCI domain; it has to be the same". But for the si_domain that isn't
going to be true, as it consists of all the PCI devices that are
identity mapped thus multiple PCI domains can be in si_domain.  The
code needs to validate the PCI domain too.

Signed-off-by: Mike Habeck <habeck@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: stable@kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

When using the 1:1 (identity) PCI DMA remapping, PCI Host Bridge devices
that do not use the IOMMU causes a kernel panic.  Fix that by not
inserting those devices into the si_domain.

Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Mike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The __intel_map_single function is not honoring the passed in DMA mask.
This results in not using the coherent DMA mask when called from
intel_alloc_coherent().

Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Reviewed-by: Mike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Mike Travis and Mike Habeck reported an issue where iova allocation
would return a range that was larger than a device's dma mask.

https://lkml.org/lkml/2011/3/29/423



The dmar initialization code will reserve all PCI MMIO regions and copy
those reservations into a domain specific iova tree.  It is possible for
one of those regions to be above the dma mask of a device.  It is typical
to allocate iovas with a 32bit mask (despite device's dma mask possibly
being larger) and cache the result until it exhausts the lower 32bit
address space.  Freeing the iova range that is >= the last iova in the
lower 32bit range when there is still an iova above the 32bit range will
corrupt the cached iova by pointing it to a region that is above 32bit.
If that region is also larger than the device's dma mask, a subsequent
allocation will return an unusable iova and cause dma failure.

Simply don't cache an iova that is above the 32bit caching boundary.

Reported-by: Mike Travis <travis@sgi.com>
Reported-by: Mike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Acked-by: Mike Travis <travis@sgi.com>
Tested-by: Mike Habeck <habeck@sgi.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

When there are a large count of PCI devices, and the pass through
option for iommu is set, much time is spent in the identity_mapping
function hunting though the iommu domains to check if a specific
device is "identity mapped".

Speed up the function by checking the cached info to see if
it's mapped to the static identity domain.

Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Mike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

The identity mapping code appears to make the assumption that if the
devices dma_mask is greater than 32bits the device can use identity
mapping.  But that is not true: take the case where we have a 40bit
device in a 44bit architecture. The device can potentially receive a
physical address that it will truncate and cause incorrect addresses
to be used.

Instead check to see if the device's dma_mask is large enough
to address the system's dma_mask.

Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Mike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Commit a97590e5

 added unlinking domains from iommus to reciprocate the
iommu from domains unlinking that was already done.  We actually want
to only do this for device domains and never for the static
identity map domain or VM domains.  The SI domain is special and
never freed, while VM domain->id lives in their own special address
space, separate from iommu->domain_ids.

In the current code, a VM can get domain->id zero, then mark that
domain unused when unbound from pci-stub.  This leads to DMAR
write faults when the device is re-bound to the host driver.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: stable@kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

There are no externally-visible changes with this. In the loop in the
internal __domain_mapping() function, we simply detect if we are mapping:
  - size >= 2MiB, and
  - virtual address aligned to 2MiB, and
  - physical address aligned to 2MiB, and
  - on hardware that supports superpages.

(and likewise for larger superpages).

We automatically use a superpage for such mappings. We never have to
worry about *breaking* superpages, since we trust that we will always
*unmap* the same range that was mapped. So all we need to do is ensure
that dma_pte_clear_range() will also cope with superpages.

Adjust pfn_to_dma_pte() to take a superpage 'level' as an argument, so
it can return a PTE at the appropriate level rather than always
extending the page tables all the way down to level 1. Again, this is
simplified by the fact that we should never encounter existing small
pages when we're creating a mapping; any old mapping that used the same
virtual range will have been entirely removed and its obsolete page
tables freed.

Provide an 'intel_iommu=sp_off' argument on the command line as a
chicken bit. Not that it should ever be required.

==

The original commit seen in the iommu-2.6.git was Youquan's
implementation (and completion) of my own half-baked code which I'd
typed into an email. Followed by half a dozen subsequent 'fixes'.

I've taken the unusual step of rewriting history and collapsing the
original commits in order to keep the main history simpler, and make
life easier for the people who are going to have to backport this to
older kernels. And also so I can give it a more coherent commit comment
which (hopefully) gives a better explanation of what's going on.

The original sequence of commits leading to identical code was:

Youquan Song (3):
      intel-iommu: super page support
      intel-iommu: Fix superpage alignment calculation error
      intel-iommu: Fix superpage level calculation error in dma_pfn_level_pte()

David Woodhouse (4):
      intel-iommu: Precalculate superpage support for dmar_domain
      intel-iommu: Fix hardware_largepage_caps()
      intel-iommu: Fix inappropriate use of superpages in __domain_mapping()
      intel-iommu: Fix phys_pfn in __domain_mapping for sglist pages

Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Fix build warnings in physmap.h:

include/linux/mtd/physmap.h:25: warning: 'struct platform_device' declared inside parameter list
include/linux/mtd/physmap.h:25: warning: its scope is only this definition or declaration, which is probably not what you want
include/linux/mtd/physmap.h:26: warning: 'struct platform_device' declared inside parameter list
include/linux/mtd/physmap.h:27: warning: 'struct platform_device' declared inside parameter list

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  AppArmor: fix oops in apparmor_setprocattr

The new instruction_pointer_set helper is defined for people who have
converted to asm-generic/ptrace.h, so don't use it generally unless
the arch needs it (in which case it has been converted).  This should
fix building of kgdb tests for arches not yet converted.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When invalid parameters are passed to apparmor_setprocattr a NULL deref
oops occurs when it tries to record an audit message. This is because
it is passing NULL for the profile parameter for aa_audit. But aa_audit
now requires that the profile passed is not NULL.

Fix this by passing the current profile on the task that is trying to
setprocattr.

Signed-off-by: Kees Cook <kees@ubuntu.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Cc: stable@kernel.org
Signed-off-by: James Morris <jmorris@namei.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  virtio_net: delay TX callbacks
  virtio: add api for delayed callbacks
  virtio_test: support event index
  vhost: support event index
  virtio_ring: support event idx feature
  virtio ring: inline function to check for events
  virtio: event index interface
  virtio: add full three-clause BSD text to headers.
  virtio balloon: kill tell-host-first logic
  virtio console: don't manually set or finalize VIRTIO_CONSOLE_F_MULTIPORT.
  drivers, block: virtio_blk: Replace cryptic number with the macro
  virtio_blk: allow re-reading config space at runtime
  lguest: remove support for VIRTIO_F_NOTIFY_ON_EMPTY.
  lguest: fix up compilation after move
  lguest: fix timer interrupt setup

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
  [IA64] wire up sendmmsg() syscall for Itanium

Add entries in unistd.h and entry.S to make this new syscall visible.

Signed-off-by: Tony Luck <tony.luck@intel.com>

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Fix mwait_play_dead() faulting on mwait-incapable cpus
  x86 idle: Fix mwait deprecation warning message

Evil merge to remove extra quote noticed by Joe Perches

Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: Cure load woes

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Put back -pg to tsc.o and add no GCOV to vread_tsc_64.o

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  autofs4: bogus dentry_unhash() added in ->unlink()
  vfs: shrink_dcache_parent before rmdir, dir rename

The Apple custom PIC only exist in some earlier machine models,
anything with an MPIC will crash on suspend if we register those
syscore ops unconditionally.

This is a regression caused by commit f5a592f7

 ("PM / PowerPC: Use
struct syscore_ops instead of sysdevs for PM")

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit cc3ce517

 (rcu: Start RCU kthreads in TASK_INTERRUPTIBLE
state) fudges a sleeping task' state, resulting in the scheduler seeing
a TASK_UNINTERRUPTIBLE task going to sleep, but a TASK_INTERRUPTIBLE
task waking up. The result is unbalanced load calculation.

The problem that patch tried to address is that the RCU threads could
stay in UNINTERRUPTIBLE state for quite a while and triggering the hung
task detector due to on-demand wake-ups.

Cure the problem differently by always giving the tasks at least one
wake-up once the CPU is fully up and running, this will kick them out of
the initial UNINTERRUPTIBLE state and into the regular INTERRUPTIBLE
wait state.

[ The alternative would be teaching kthread_create() to start threads as
  INTERRUPTIBLE but that needs a tad more thought. ]

Reported-by: Damien Wyart <damien.wyart@free.fr>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul E. McKenney <paul.mckenney@linaro.org>
Link: http://lkml.kernel.org/r/13067552...

A logic error in mwait_play_dead() causes the kernel to use
mwait even on cpus which don't support it, such as KVM virtual
cpus.

Introduced by:

  349c004e: x86: A fast way to check capabilities of the current cpu

Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=36222


Reported-by: Török Edwin <edwintorok@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1306758237-9327-1-git-send-email-avi@redhat.com


Signed-off-by: Ingo Molnar <mingo@elte.hu>

Fix:

  arch/x86/kernel/process.c:645:1: warning: unknown escape sequence '\i'

due to missing escape backslash, introduced by this commit:

  5d4c47e0

: x86 idle: deprecate mwait_idle() and "idle=mwait" cmdline param

Signed-off-by: Borislav Petkov <bp@alien8.de>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1306748286-24701-1-git-send-email-bp@alien8.de


Signed-off-by: Ingo Molnar <mingo@elte.hu>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

The dentry_unhash push-down series missed that shink_dcache_parent needs to
be called prior to rmdir or dir rename to clear DCACHE_REFERENCED and
allow efficient dentry reclaim.

Reported-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Ask for delayed callbacks on TX ring full, to give the
other side more of a chance to make progress.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Add an API that tells the other side that callbacks
should be delayed until a lot of work has been done.
Implement using the new event_idx feature.

Note: it might seem advantageous to let the drivers
ask for a callback after a specific capacity has
been reached. However, as a single head can
free many entries in the descriptor table,
we don't really have a clue about capacity
until get_buf is called. The API is the simplest
to implement at the moment, we'll see what kind of
hints drivers can pass when there's more than one
user of the feature.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Add ability to test the new event idx feature,
enable by default.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Support the new event index feature. When acked,
utilize it to reduce the # of interrupts sent to the guest.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Support for the new event idx feature:
1. When enabling interrupts, publish the current avail index
   value to the host to get interrupts on the next update.
2. Use the new avail_event feature to reduce the number
   of exits from the guest.

Simple test with the simulator:

[virtio]# time ./virtio_test
spurious wakeus: 0x7

real    0m0.169s
user    0m0.140s
sys     0m0.019s
[virtio]# time ./virtio_test --no-event-idx
spurious wakeus: 0x11

real    0m0.649s
user    0m0.295s
sys     0m0.335s

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

With the new used_event and avail_event and features, both
host and guest need similar logic to check whether events are
enabled, so it helps to put the common code in the header.

Note that Xen has similar logic for notification hold-off
in include/xen/interface/io/ring.h with req_event and req_prod
corresponding to event_idx + 1 and new_idx respectively.
+1 comes from the fact that req_event and req_prod in Xen start at 1,
while event index in virtio starts at 0.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>