A new PMU type, perf_kprobe is added. Based on attr from perf_event_open(),
perf_kprobe creates a kprobe (or kretprobe) for the perf_event. This
kprobe is private to this perf_event, and thus not added to global
lists, and not available in tracefs.

Two functions, create_local_trace_kprobe() and
destroy_local_trace_kprobe()  are added to created and destroy these
local trace_kprobe.
Signed-off-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: NYonghong Song <yhs@fb.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Cc: <daniel@iogearbox.net>
Cc: <davem@davemloft.net>
Cc: <kernel-team@fb.com>
Cc: <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171206224518.3598254-6-songliubraving@fb.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Since i_version is mostly treated as an opaque value, we can exploit that
fact to avoid incrementing it when no one is watching. With that change,
we can avoid incrementing the counter on writes, unless someone has
queried for it since it was last incremented. If the a/c/mtime don't
change, and the i_version hasn't changed, then there's no need to dirty
the inode metadata on a write.

Convert the i_version counter to an atomic64_t, and use the lowest order
bit to hold a flag that will tell whether anyone has queried the value
since it was last incremented.

When we go to maybe increment it, we fetch the value and check the flag
bit.  If it's clear then we don't need to do anything if the update
isn't being forced.

If we do need to update, then we increment the counter by 2, and clear
the flag bit, and then use a CAS op to swap it into place. If that
works, we return true. If it doesn't then do it again with the value
that we fetch from the CAS operation.

On the query side, if the flag is already set, then we just shift the
value down by 1 bit and return it. Otherwise, we set the flag in our
on-stack value and again use cmpxchg to swap it into place if it hasn't
changed. If it has, then we use the value from the cmpxchg as the new
"old" value and try again.

This method allows us to avoid incrementing the counter on writes (and
dirtying the metadata) under typical workloads. We only need to increment
if it has been queried since it was last changed.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Acked-by: NDave Chinner <dchinner@redhat.com>
Tested-by: NKrzysztof Kozlowski <krzk@kernel.org>

The rationale for taking the i_lock when incrementing this value is
lost in antiquity. The readers of the field don't take it (at least
not universally), so my assumption is that it was only done here to
serialize incrementors.

If that is indeed the case, then we can drop the i_lock from this
codepath and treat it as a atomic64_t for the purposes of
incrementing it. This allows us to use inode_inc_iversion without
any danger of lock inversion.

Note that the read side is not fetched atomically with this change.
The assumption here is that that is not a critical issue since the
i_version is not fully synchronized with anything else anyway.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NJan Kara <jack@suse.cz>

Add a documentation blob that explains what the i_version field is, how
it is expected to work, and how it is currently implemented by various
filesystems.

We already have inode_inc_iversion. Add several other functions for
manipulating and accessing the i_version counter. For now, the
implementation is trivial and basically works the way that all of the
open-coded i_version accesses work today.

Future patches will convert existing users of i_version to use the new
API, and then convert the backend implementation to do things more
efficiently.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NJan Kara <jack@suse.cz>

In this patch, consumers are allowed to set suspend voltage, and this
actually just set the "uV" in constraint::regulator_state, when the
regulator_suspend_late() was called by PM core through callback when
the system is entering into suspend, the regulator device would act
suspend activity then.

And it assumes that if any consumer set suspend voltage, the regulator
device should be enabled in the suspend state.  And if the suspend
voltage of a regulator device for all consumers was set zero, the
regulator device would be off in the suspend state.

This patch also provides a new function hook to regulator devices for
resuming from suspend states.
Signed-off-by: NChunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

Regualtor suspend/resume functions should only be called by PM suspend
core via registering dev_pm_ops, and regulator devices should implement
the callback functions.  Thus, any regulator consumer shouldn't call
the regulator suspend/resume functions directly.

In order to avoid compile errors, two empty functions with the same name
still be left for the time being.
Signed-off-by: NChunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

The items "disabled" and "enabled" are a little redundant, since only one
of them would be set to record if the regulator device should keep on
or be switched to off in suspend states.

So in this patch, the "disabled" was removed, only leave the "enabled":
  - enabled == 1 for regulator-on-in-suspend
  - enabled == 0 for regulator-off-in-suspend
  - enabled == -1 means do nothing when entering suspend mode.
Signed-off-by: NChunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

There's a risk that a kernel which has full retpoline mitigations becomes
vulnerable when a module gets loaded that hasn't been compiled with the
right compiler or the right option.

To enable detection of that mismatch at module load time, add a module info
string "retpoline" at build time when the module was compiled with
retpoline support. This only covers compiled C source, but assembler source
or prebuilt object files are not checked.

If a retpoline enabled kernel detects a non retpoline protected module at
load time, print a warning and report it in the sysfs vulnerability file.

[ tglx: Massaged changelog ]
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: jeyu@kernel.org
Cc: arjan@linux.intel.com
Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org

This reverts commit 6cfb521a.

Turns out distros do not want to make retpoline as part of their "ABI",
so this patch should not have been merged.  Sorry Andi, this was my
fault, I suggested it when your original patch was the "correct" way of
doing this instead.
Reported-by: NJiri Kosina <jikos@kernel.org>
Fixes: 6cfb521a ("module: Add retpoline tag to VERMAGIC")
Acked-by: NAndi Kleen <ak@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: rusty@rustcorp.com.au
Cc: arjan.van.de.ven@intel.com
Cc: jeyu@kernel.org
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Tejun reported the following cpu-hotplug lock (percpu-rwsem) read recursion:

  tg_set_cfs_bandwidth()
    get_online_cpus()
      cpus_read_lock()

    cfs_bandwidth_usage_inc()
      static_key_slow_inc()
        cpus_read_lock()
Reported-by: NTejun Heo <tj@kernel.org>
Tested-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180122215328.GP3397@worktopSigned-off-by: NIngo Molnar <mingo@kernel.org>

The function tracer can create a dynamically allocated trampoline that is
called by the function mcount or fentry hook that is used to call the
function callback that is registered. The problem is that the orc undwinder
will bail if it encounters one of these trampolines. This breaks the stack
trace of function callbacks, which include the stack tracer and setting the
stack trace for individual functions.

Since these dynamic trampolines are basically copies of the static ftrace
trampolines defined in ftrace_*.S, we do not need to create new orc entries
for the dynamic trampolines. Finding the return address on the stack will be
identical as the functions that were copied to create the dynamic
trampolines. When encountering a ftrace dynamic trampoline, we can just use
the orc entry of the ftrace static function that was copied for that
trampoline.
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

Tetsuo reported random crashes under memory pressure on 32-bit x86
system and tracked down to change that introduced
page_vma_mapped_walk().

The root cause of the issue is the faulty pointer math in check_pte().
As ->pte may point to an arbitrary page we have to check that they are
belong to the section before doing math. Otherwise it may lead to weird
results.

It wasn't noticed until now as mem_map[] is virtually contiguous on
flatmem or vmemmap sparsemem. Pointer arithmetic just works against all
'struct page' pointers. But with classic sparsemem, it doesn't because
each section memap is allocated separately and so consecutive pfns
crossing two sections might have struct pages at completely unrelated
addresses.

Let's restructure code a bit and replace pointer arithmetic with
operations on pfns.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-and-tested-by: NTetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Acked-by: NMichal Hocko <mhocko@suse.com>
Fixes: ace71a19 ("mm: introduce page_vma_mapped_walk()")
Cc: stable@vger.kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

GCC-4.4.4 raises errors when assigning a parameter in an anonymous
union, leading to this kind of failure:

drivers/mtd/nand/marvell_nand.c:1936:
    warning: missing braces around initializer
    warning: (near initialization for '(anonymous)[1].<anonymous>')
    error: unknown field 'data' specified in initializer
    error: unknown field 'addr' specified in initializer

Work around the situation by naming these unions.

Fixes: 8878b126 ("mtd: nand: add ->exec_op() implementation")
Reported-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NMiquel Raynal <miquel.raynal@free-electrons.com>
Tested-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The previous patch removed all users of these two functions. Hence
also remove the functions themselves.
Reviewed-by: NMike Snitzer <snitzer@redhat.com>
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch avoids that workloads with large block sizes (megabytes)
can trigger the following call stack with the ib_srpt driver (that
driver is the only driver that chains scatterlists allocated by
sgl_alloc_order()):

BUG: Bad page state in process kworker/0:1H  pfn:2423a78
page:fffffb03d08e9e00 count:-3 mapcount:0 mapping:          (null) index:0x0
flags: 0x57ffffc0000000()
raw: 0057ffffc0000000 0000000000000000 0000000000000000 fffffffdffffffff
raw: dead000000000100 dead000000000200 0000000000000000 0000000000000000
page dumped because: nonzero _count
CPU: 0 PID: 733 Comm: kworker/0:1H Tainted: G          I      4.15.0-rc7.bart+ #1
Hardware name: HP ProLiant DL380 G7, BIOS P67 08/16/2015
Workqueue: ib-comp-wq ib_cq_poll_work [ib_core]
Call Trace:
 dump_stack+0x5c/0x83
 bad_page+0xf5/0x10f
 get_page_from_freelist+0xa46/0x11b0
 __alloc_pages_nodemask+0x103/0x290
 sgl_alloc_order+0x101/0x180
 target_alloc_sgl+0x2c/0x40 [target_core_mod]
 srpt_alloc_rw_ctxs+0x173/0x2d0 [ib_srpt]
 srpt_handle_new_iu+0x61e/0x7f0 [ib_srpt]
 __ib_process_cq+0x55/0xa0 [ib_core]
 ib_cq_poll_work+0x1b/0x60 [ib_core]
 process_one_work+0x141/0x340
 worker_thread+0x47/0x3e0
 kthread+0xf5/0x130
 ret_from_fork+0x1f/0x30

Fixes: e80a0af4 ("lib/scatterlist: Introduce sgl_alloc() and sgl_free()")
Reported-by: NLaurence Oberman <loberman@redhat.com>
Tested-by: NLaurence Oberman <loberman@redhat.com>
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Cc: Laurence Oberman <loberman@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Without this patch, I drown in a sea of unknown attribute warnings

Link: http://lkml.kernel.org/r/20180117024539.27354-1-willy@infradead.orgSigned-off-by: NMatthew Wilcox <mawilcox@microsoft.com>
Acked-by: NKees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

These two functions are only called from inside the block layer so
unexport them.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

These users of lockdep_is_held() either wanted lockdep_is_held to
take a const pointer, or would benefit from providing a const pointer.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Link: https://lkml.kernel.org/r/20180117151414.23686-4-willy@infradead.org

There are several places in the kernel which would like to pass a const
pointer to lockdep_is_held().  Constify the entire path so nobody has to
trick the compiler.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Link: https://lkml.kernel.org/r/20180117151414.23686-3-willy@infradead.org

Like mmc_can_gpio_cd(), mmc_can_gpio_ro() will also be useful for host
drivers to know whether GPIO write-protect detection is supported.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Define the bit positions instead of macros using the magic values,
and move the expanded helpers to calculate the size and size unit into
the implementation C file.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NLogan Gunthorpe <logang@deltatee.com>

Expand INIT_STRUCT_PID in the single place that uses it and then remove it.
There doesn't seem any point in the macro.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Tested-by: NTony Luck <tony.luck@intel.com>
Tested-by: Will Deacon <will.deacon@arm.com> (arm64)
Tested-by: NPalmer Dabbelt <palmer@sifive.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>

There doesn't seem to be any need to have the INIT_SIGNALS and INIT_SIGHAND
macros, so expand them in their single places of use and remove them.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Tested-by: NTony Luck <tony.luck@intel.com>
Tested-by: Will Deacon <will.deacon@arm.com> (arm64)
Tested-by: NPalmer Dabbelt <palmer@sifive.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>

Expand various INIT_* macros into the single places they're used in
init/init_task.c and remove them.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Tested-by: NTony Luck <tony.luck@intel.com>
Tested-by: Will Deacon <will.deacon@arm.com> (arm64)
Tested-by: NPalmer Dabbelt <palmer@sifive.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>

It's no longer necessary to have an INIT_TASK() macro, and this can be
expanded into the one place it is now used and removed.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Tested-by: NTony Luck <tony.luck@intel.com>
Tested-by: Will Deacon <will.deacon@arm.com> (arm64)
Tested-by: NPalmer Dabbelt <palmer@sifive.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>

Add a marker for retpoline to the module VERMAGIC. This catches the case
when a non RETPOLINE compiled module gets loaded into a retpoline kernel,
making it insecure.

It doesn't handle the case when retpoline has been runtime disabled.  Even
in this case the match of the retcompile status will be enforced.  This
implies that even with retpoline run time disabled all modules loaded need
to be recompiled.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NDavid Woodhouse <dwmw@amazon.co.uk>
Cc: rusty@rustcorp.com.au
Cc: arjan.van.de.ven@intel.com
Cc: jeyu@kernel.org
Cc: torvalds@linux-foundation.org
Link: https://lkml.kernel.org/r/20180116205228.4890-1-andi@firstfloor.org

Some older compilers (gcc-4.4 through 4.6 in particular) struggle
with the way that blkg_rwstat_read() returns a structure, leading
to excessive stack usage and rather inefficient code:

block/blk-cgroup.c: In function 'blkg_destroy':
block/blk-cgroup.c:354:1: error: the frame size of 1296 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
block/cfq-iosched.c: In function 'cfqg_stats_add_aux':
block/cfq-iosched.c:753:1: error: the frame size of 1928 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
block/bfq-cgroup.c: In function 'bfqg_stats_add_aux':
block/bfq-cgroup.c:299:1: error: the frame size of 1928 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]

I also notice that there is no point in using atomic accesses
for the local variables, so storing the temporaries in simple 'u64'
variables not only avoids the stack usage on older compilers but
also improves the object code on modern versions.

Fixes: e6269c44 ("blkcg: add blkg_[rw]stat->aux_cnt and replace cfq_group->dead_stats with it")
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch brings basic support for the Linux Driver Model to the
NuBus subsystem.

For flexibility, the matching of boards with drivers is left up to the
drivers. This is also the approach taken by NetBSD. A board may have
many functions, and drivers may have to consider many functional
resources and board resources in order to match a device.

This implementation does not bind drivers to resources (nor does it bind
many drivers to the same board). Apple's NuBus declaration ROM design
is flexible enough to allow that, but I don't see a need to support it
as we don't use the "slot zero" resources (in the main logic board ROM).

Eliminate the global nubus_boards linked list by rewriting the procfs
board iterator around bus_for_each_dev(). Hence the nubus device refcount
can be used to determine the lifespan of board objects.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: NStan Johnson <userm57@yahoo.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>

This increases code re-use and improves readability.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Tested-by: NStan Johnson <userm57@yahoo.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>

It is misleading to call a functional resource a "device". In adopting
the Linux Driver Model, the struct device will be embedded in struct
nubus_board. That will compound the terminlogy problem because drivers
will bind with boards, not with functional resources. Avoid this by
renaming struct nubus_dev as struct nubus_rsrc. "Functional resource"
is the vendor's terminology so this helps avoid confusion.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Tested-by: NStan Johnson <userm57@yahoo.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>

The /proc/bus/nubus/s/ directory tree for any slot s is missing a lot
of information. The struct file_operations methods have long been left
unimplemented (hence the familiar compile-time warning, "Need to set
some I/O handlers here").

Slot resources have a complex structure which varies depending on board
function. The logic for interpreting these ROM data structures is found
in nubus.c. Let's not duplicate that logic in proc.c.

Create the /proc/bus/nubus/s/ inodes while scanning slot s. During
descent through slot resource subdirectories, call the new
nubus_proc_add_foo() functions to create the procfs inodes.

Also add a new function, nubus_seq_write_rsrc_mem(), to write the
contents of a particular slot resource to a given seq_file. This is
used by the procfs file_operations methods, to finally give userspace
access to slot ROM information, such as the available video modes.
Tested-by: NStan Johnson <userm57@yahoo.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>

Tested-by: NStan Johnson <userm57@yahoo.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>

Eliminate unused values from struct nubus_dev to save wasted memory
(a Radius PrecisionColor 24X card has about 95 functional resources
and up to six such cards may be fitted). Also remove redundant static
variable initialization, an unreachable !MACH_IS_MAC conditional,
the unused nubus_find_device() function, the bogus get_nubus_list()
prototype and the pointless card_present temporary variable.
Tested-by: NStan Johnson <userm57@yahoo.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>

This patch fixes the following WARNING.

proc_dir_entry 'nubus/a' already registered
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Tainted: G        W       4.13.0-00036-gd57552077387 #1
Stack from 01c1bd9c:
        01c1bd9c 003c2c8b 01c1bdc0 0001b0fe 00000000 00322f4a 01c43a20 01c43b0c
        01c8c420 01c1bde8 0001b1b8 003a4ac3 00000148 000faa26 00000009 00000000
        01c1bde0 003a4b6c 01c1bdfc 01c1be20 000faa26 003a4ac3 00000148 003a4b6c
        01c43a71 01c8c471 01c10000 00326430 0043d00c 00000005 01c71a00 0020bce0
        00322964 01c1be38 000fac04 01c43a20 01c8c420 01c1bee0 01c8c420 01c1be50
        000fac4c 01c1bee0 00000000 01c43a20 00000000 01c1bee8 0020bd26 01c1bee0
Call Trace: [<0001b0fe>] __warn+0xae/0xde
 [<00322f4a>] memcmp+0x0/0x5c
 [<0001b1b8>] warn_slowpath_fmt+0x2e/0x36
 [<000faa26>] proc_register+0xbe/0xd8
 [<000faa26>] proc_register+0xbe/0xd8
 [<00326430>] sprintf+0x0/0x20
 [<0020bce0>] nubus_proc_attach_device+0x0/0x1b8
 [<00322964>] strcpy+0x0/0x22
 [<000fac04>] proc_mkdir_data+0x64/0x96
 [<000fac4c>] proc_mkdir+0x16/0x1c
 [<0020bd26>] nubus_proc_attach_device+0x46/0x1b8
 [<0020bce0>] nubus_proc_attach_device+0x0/0x1b8
 [<00322964>] strcpy+0x0/0x22
 [<00001ba6>] kernel_pg_dir+0xba6/0x1000
 [<004339a2>] proc_bus_nubus_add_devices+0x1a/0x2e
 [<000faa40>] proc_create_data+0x0/0xf2
 [<0003297c>] parse_args+0x0/0x2d4
 [<00433a08>] nubus_proc_init+0x52/0x5a
 [<00433944>] nubus_init+0x0/0x44
 [<00433982>] nubus_init+0x3e/0x44
 [<000020dc>] do_one_initcall+0x38/0x196
 [<000020a4>] do_one_initcall+0x0/0x196
 [<0003297c>] parse_args+0x0/0x2d4
 [<00322964>] strcpy+0x0/0x22
 [<00040004>] __up_read+0xe/0x40
 [<004231d4>] repair_env_string+0x0/0x7a
 [<0042312e>] kernel_init_freeable+0xee/0x194
 [<00423146>] kernel_init_freeable+0x106/0x194
 [<00433944>] nubus_init+0x0/0x44
 [<000a6000>] kfree+0x0/0x156
 [<0032768c>] kernel_init+0x0/0xda
 [<00327698>] kernel_init+0xc/0xda
 [<0032768c>] kernel_init+0x0/0xda
 [<00002a90>] ret_from_kernel_thread+0xc/0x14
---[ end trace 14a6d619908ea253 ]---
------------[ cut here ]------------

This gets repeated with each additional functional reasource.

The problem here is the call to proc_mkdir() when the directory already
exists. Each nubus_board gets a directory, such as /proc/bus/nubus/s/
where s is the hex slot number. Therefore, store the 'procdir' pointer
in struct nubus_board instead of struct nubus_dev.
Tested-by: NStan Johnson <userm57@yahoo.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>

This fixes a couple of warnings from 'make W=1':
drivers/nubus/nubus.c:790: warning: no previous prototype for 'nubus_probe_slot'
drivers/nubus/nubus.c:824: warning: no previous prototype for 'nubus_scan_bus'
Tested-by: NStan Johnson <userm57@yahoo.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>

Due to the '#ifdef __KERNEL__' being located in the wrong place, some
definitions from the kernel API were placed in the UAPI header during
the scripted header split. Fix this. Also, remove the duplicate comment
which is only relevant to the UAPI header.

Fixes: 607ca46e ("UAPI: (Scripted) Disintegrate include/linux")
Tested-by: NStan Johnson <userm57@yahoo.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>

Check array indices. Avoid sprintf. Use buffers of sufficient size.
Use appropriate types for array length parameters.
Tested-by: NStan Johnson <userm57@yahoo.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>

hrtimer callbacks are always invoked in hard interrupt context. Several
users in tree require soft interrupt context for their callbacks and
achieve this by combining a hrtimer with a tasklet. The hrtimer schedules
the tasklet in hard interrupt context and the tasklet callback gets invoked
in softirq context later.

That's suboptimal and aside of that the real-time patch moves most of the
hrtimers into softirq context. So adding native support for hrtimers
expiring in softirq context is a valuable extension for both mainline and
the RT patch set.

Each valid hrtimer clock id has two associated hrtimer clock bases: one for
timers expiring in hardirq context and one for timers expiring in softirq
context.

Implement the functionality to associate a hrtimer with the hard or softirq
related clock bases and update the relevant functions to take them into
account when the next expiry time needs to be evaluated.

Add a check into the hard interrupt context handler functions to check
whether the first expiring softirq based timer has expired. If it's expired
the softirq is raised and the accounting of softirq based timers to
evaluate the next expiry time for programming the timer hardware is skipped
until the softirq processing has finished. At the end of the softirq
processing the regular processing is resumed.
Suggested-by: NThomas Gleixner <tglx@linutronix.de>
Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NAnna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: keescook@chromium.org
Link: http://lkml.kernel.org/r/20171221104205.7269-29-anna-maria@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

Before commit:

  e33a9bba ("sched/core: move IO scheduling accounting from io_schedule_timeout() into scheduler")

delayacct_blkio_end() was called after context-switching into the task which
completed I/O.

This resulted in double counting: the task would account a delay both waiting
for I/O and for time spent in the runqueue.

With e33a9bba, delayacct_blkio_end() is called by try_to_wake_up().
In ttwu, we have not yet context-switched. This is more correct, in that
the delay accounting ends when the I/O is complete.

But delayacct_blkio_end() relies on 'get_current()', and we have not yet
context-switched into the task whose I/O completed. This results in the
wrong task having its delay accounting statistics updated.

Instead of doing that, pass the task_struct being woken to delayacct_blkio_end(),
so that it can update the statistics of the correct task.
Signed-off-by: NJosh Snyder <joshs@netflix.com>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NBalbir Singh <bsingharora@gmail.com>
Cc: <stable@vger.kernel.org>
Cc: Brendan Gregg <bgregg@netflix.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-block@vger.kernel.org
Fixes: e33a9bba ("sched/core: move IO scheduling accounting from io_schedule_timeout() into scheduler")
Link: http://lkml.kernel.org/r/1513613712-571-1-git-send-email-joshs@netflix.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Currently hrtimer callback functions are always executed in hard interrupt
context. Users of hrtimers, which need their timer function to be executed
in soft interrupt context, make use of tasklets to get the proper context.

Add additional hrtimer clock bases for timers which must expire in softirq
context, so the detour via the tasklet can be avoided. This is also
required for RT, where the majority of hrtimer is moved into softirq
hrtimer context.

The selection of the expiry mode happens via a mode bit. Introduce
HRTIMER_MODE_SOFT and the matching combinations with the ABS/REL/PINNED
bits and update the decoding of hrtimer_mode in tracepoints.
Signed-off-by: NAnna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: keescook@chromium.org
Link: http://lkml.kernel.org/r/20171221104205.7269-27-anna-maria@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>