Pragmatically it couldn't be wrong to cast pointers to long to compare
them (since all kernel addresses are in the top half of VA space),
but it's more correct to cast to unsigned long.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

If we are single-stepping and make a syscall, we call ptrace_notify()
explicitly on the return path back to user space, since we are returning
to a pc value set artificially to the next instruction, and otherwise
we won't register that we stepped over the syscall instruction (swint1).
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

This allows the later-panicking tiles to wait in a lower power state
until they get interrupted with an smp_send_stop().
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

This avoids the hardware istream prefetcher doing unnecessary work.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

This is more standard and avoids having to remember what units
the options actually take.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

We should be holding the init_mm.page_table_lock in shatter_huge_page()
since we are modifying the kernel page tables.  Then, only if we are
walking the other root page tables to update them, do we want to take
the pgd_lock.

Add a comment about taking the pgd_lock that we always do it with
interrupts disabled and therefore are not at risk from the tlbflush
IPI deadlock as is seen on x86.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

We were failing to track the memory when we allocated it.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

We were carefully computing a value to use for the number of loops
to spin for, and then ignoring it.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

Previously we only handled kernels up to a single huge page in size.
Now we create additional PTEs appropriately.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

If we took a page fault while we had interrupts disabled, we
shouldn't enable them in the page fault handler.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

We make sure not to try to set the home for an MMIO PTE (on tilegx)
or a PTE that isn't referencing memory managed by Linux.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

Doing so raises the possibility of self-deadlock if we are waiting
for a backtrace for an oprofile or perf interrupt while we are
in the middle of migrating our own stack page.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

Not associated with any code changes, so I'm just lumping these
comment changes into a commit by themselves.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

We now respond to MEM_ERROR traps (e.g. an atomic instruction to
non-cacheable memory) with a SIGBUS.

We also no longer generate a console crash message if a user
process die due to a SIGTRAP.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

In certain circumstances we need to do a bunch of jump-and-link
instructions to fill the hardware return-address stack with nonzero values.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

Fix a long-standing bug in the stack backtracer where we would print
garbage to the console instead of kernel function names, if the kernel
wasn't built with symbol support (e.g. mboot).

Make sure to tag every line of userspace backtrace output if we actually
have the mmap_sem, since that way if there's no tag, we know that it's
because we couldn't trylock the semaphore.

Stop doing a TLB flush and examining page tables during backtrace.
Instead, just trust that __copy_from_user_inatomic() will properly fault
and return a failure, which it should do in all cases.

Fix a latent bug where the backtracer would directly examine a signal
context in user space, rather than copying it safely to kernel memory
first.  This meant that a race with another thread could potentially
have caused a kernel panic.

Guard against unaligned sp when trying to restart backtrace at an
interrupt or signal handler point in the kernel backtracer.

Report kernel symbolic information for the call instruction rather
than for the following instruction.  We still report the actual numeric
address corresponding to the instruction after the call, for the sake
of consistency with the normal expectations for stack backtracers.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

Add a comment explaining why this is important, and add a CFLAGS_REMOVE
clause to the Makefile to make sure it happens.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

With lockstat we can end up trying to get a backtrace before
"high_memory" is initialized, so don't worry about range testing
if it is zero.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

This avoids assigning IRQ 0 to PCI devices, because we've seen that
doesn't always work well.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

Fix some signedness and variable usage warnings in change_bit()
and test_and_change_bit().
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

It still returns whether @v was not @u, not the old value,
unlike __atomic_add_unless().
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arun Sharma <asharma@fb.com>

We aren't yet using this definition in the kernel, but fix it up
before someone goes looking for it.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

It's fixed at half the VA space and there's no point in configuring it.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

We switched to using "tilepro" for the 32-bit stuff a while ago,
but missed this one usage.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

Looks like a cut and paste bug from the x86 version.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

Commit bd119c69

    "Disintegrate asm/system.h for Tile"

created the asm/switch_to.h file, but did not add an include
of it to all its users.

Also, commit b4816afa

        "Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h"

introduced the concept of asm/cmpxchg.h but the tile arch
never got one.  Fork the cmpxchg content out of the asm/atomic.h
file to create one.
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

Pull virtio S3 support patches from Amit Shah:
 "Turns out S3 is not different from S4 for virtio devices: the device
  is assumed to be reset, so the host and guest state are to be assumed
  to be out of sync upon resume.  We handle the S4 case with exactly the
  same scenario, so just point the suspend/resume routines to the
  freeze/restore ones.

  Once that is done, we also use the PM API's macro to initialise the
  sleep functions.

  A couple of cleanups are included: there's no need for special thaw
  processing in the balloon driver, so that's addressed in patches 1 and
  2.

  Testing: both S3 and S4 support have been tested using these patches
  using a similar method used earlier during S4 patch development: a
  guest is started with virtio-blk as the only disk, a virtio network
  card, a virtio-serial port and a virtio balloon device.  Ping from
  guest to host, dd /dev/zero to a file on the disk, and IO from the
  host on the virtio-serial port, all at once, while exercising S4 and
  S3 (separately) were tested.  They all continue to work fine after
  resume.  virtio balloon values too were tested by inflating and
  deflating the balloon."

Pulling from Amit, since Rusty is off getting married (and presumably
shaving people).

* 's3-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/amit/virtio-console:
  virtio-pci: switch to PM ops macro to initialise PM functions
  virtio-pci: S3 support
  virtio-pci: drop restore_common()
  virtio: drop thaw PM operation
  virtio: balloon: Allow stats update after restore from S4

Pull second try at vfs part d#2 from Al Viro:
 "Miklos' first series (with do_lookup() rewrite split into edible
  chunks) + assorted bits and pieces.

  The 'untangling of do_lookup()' series is is a splitup of what used to
  be a monolithic patch from Miklos, so this series is basically "how do
  I convince myself that his patch is correct (or find a hole in it)".
  No holes found and I like the resulting cleanup, so in it went..."

Changes from try 1: Fix a boot problem with selinux, and commit messages
prettied up a bit.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (24 commits)
  vfs: fix out-of-date dentry_unhash() comment
  vfs: split __lookup_hash
  untangling do_lookup() - take __lookup_hash()-calling case out of line.
  untangling do_lookup() - switch to calling __lookup_hash()
  untangling do_lookup() - merge d_alloc_and_lookup() callers
  untangling do_lookup() - merge failure exits in !dentry case
  untangling do_lookup() - massage !dentry case towards __lookup_hash()
  untangling do_lookup() - get rid of need_reval in !dentry case
  untangling do_lookup() - eliminate a loop.
  untangling do_lookup() - expand the area under ->i_mutex
  untangling do_lookup() - isolate !dentry stuff from the rest of it.
  vfs: move MAY_EXEC check from __lookup_hash()
  vfs: don't revalidate just looked up dentry
  vfs: fix d_need_lookup/d_revalidate order in do_lookup
  ext3: move headers to fs/ext3/
  migrate ext2_fs.h guts to fs/ext2/ext2.h
  new helper: ext2_image_size()
  get rid of pointless includes of ext2_fs.h
  ext2: No longer export ext2_fs.h to user space
  mtdchar: kill persistently held vfsmount
  ...

Pull scheduler fixes from Ingo Molnar.

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix incorrect usage of for_each_cpu_mask() in select_fallback_rq()
  sched: Fix __schedule_bug() output when called from an interrupt
  sched/arch: Introduce the finish_arch_post_lock_switch() scheduler callback

Pull perf updates and fixes from Ingo Molnar:
 "It's mostly fixes, but there's also two late items:

   - preliminary GTK GUI support for perf report
   - PMU raw event format descriptors in sysfs, to be parsed by tooling

  The raw event format in sysfs is a new ABI.  For example for the 'CPU'
  PMU we have:

    aldebaran:~> ll /sys/bus/event_source/devices/cpu/format/*
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/any
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/cmask
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/edge
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/event
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/inv
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/offcore_rsp
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/pc
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/umask

  those lists of fields contain a specific format:

    aldebaran:~> cat /sys/bus/event_source/devices/cpu/format/offcore_rsp
    config1:0-63

  So, those who wish to specify raw events can now use the following
  event format:

    -e cpu/cmask=1,event=2,umask=3

  Most people will not want to specify any events (let alone raw
  events), they'll just use whatever default event the tools use.

  But for more obscure PMU events that have no cross-architecture
  generic events the above syntax is more usable and a bit more
  structured than specifying hex numbers."

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
  perf tools: Remove auto-generated bison/flex files
  perf annotate: Fix off by one symbol hist size allocation and hit accounting
  perf tools: Add missing ref-cycles event back to event parser
  perf annotate: addr2line wants addresses in same format as objdump
  perf probe: Finder fails to resolve function name to address
  tracing: Fix ent_size in trace output
  perf symbols: Handle NULL dso in dso__name_len
  perf symbols: Do not include libgen.h
  perf tools: Fix bug in raw sample parsing
  perf tools: Fix display of first level of callchains
  perf tools: Switch module.h into export.h
  perf: Move mmap page data_head offset assertion out of header
  perf: Fix mmap_page capabilities and docs
  perf diff: Fix to work with new hists design
  perf tools: Fix modifier to be applied on correct events
  perf tools: Fix various casting issues for 32 bits
  perf tools: Simplify event_read_id exit path
  tracing: Fix ftrace stack trace entries
  tracing: Move the tracing_on/off() declarations into CONFIG_TRACING
  perf report: Add a simple GTK2-based 'perf report' browser
  ...

Pull PARISC misc updates from James Bottomley:
 "This is a couple of minor updates (fixing lws futex locking and
  removing some obsolete cpu_*_map calls)."

* tag 'parisc-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
  [PARISC] remove references to cpu_*_map.
  [PARISC] futex: Use same lock set as lws calls

Pull SCSI updates from James Bottomley:
 "This is primarily another round of driver updates (lpfc, bfa, fcoe,
  ipr) plus a new ufshcd driver.  There shouldn't be anything
  controversial in here (The final deletion of scsi proc_ops which
  caused some build breakage has been held over until the next merge
  window to give us more time to stabilise it).

  I'm afraid, with me moving continents at exactly the wrong time,
  anything submitted after the merge window opened has been held over to
  the next merge window."

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (63 commits)
  [SCSI] ipr: Driver version 2.5.3
  [SCSI] ipr: Increase alignment boundary of command blocks
  [SCSI] ipr: Increase max concurrent oustanding commands
  [SCSI] ipr: Remove unnecessary memory barriers
  [SCSI] ipr: Remove unnecessary interrupt clearing on new adapters
  [SCSI] ipr: Fix target id allocation re-use problem
  [SCSI] atp870u, mpt2sas, qla4xxx use pci_dev->revision
  [SCSI] fcoe: Drop the rtnl_mutex before calling fcoe_ctlr_link_up
  [SCSI] bfa: Update the driver version to 3.0.23.0
  [SCSI] bfa: BSG and User interface fixes.
  [SCSI] bfa: Fix to avoid vport delete hang on request queue full scenario.
  [SCSI] bfa: Move service parameter programming logic into firmware.
  [SCSI] bfa: Revised Fabric Assigned Address(FAA) feature implementation.
  [SCSI] bfa: Flash controller IOC pll init fixes.
  [SCSI] bfa: Serialize the IOC hw semaphore unlock logic.
  [SCSI] bfa: Modify ISR to process pending completions
  [SCSI] bfa: Add fc host issue lip support
  [SCSI] mpt2sas: remove extraneous sas_log_info messages
  [SCSI] libfc: fcoe_transport_create fails in single-CPU environment
  [SCSI] fcoe: reduce contention for fcoe_rx_list lock [v2]
  ...

64252c75 "vfs: remove dget() from
dentry_unhash()" changed the implementation but not the comment.

Cc: Sage Weil <sage@newdream.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Split __lookup_hash into two component functions:

 lookup_dcache - tries cached lookup, returns whether real lookup is needed
 lookup_real - calls i_op->lookup

This eliminates code duplication between d_alloc_and_lookup() and
d_inode_lookup().
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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

now we have __lookup_hash() open-coded if !dentry case;
just call the damn thing instead...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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

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