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

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, irq: Allow 0xff for /proc/irq/[n]/smp_affinity on an 8-cpu system
  Makefile: Unexport LC_ALL instead of clearing it
  x86: Fix objdump version check in arch/x86/tools/chkobjdump.awk
  x86: Reenable TSC sync check at boot, even with NONSTOP_TSC
  x86: Don't use POSIX character classes in gen-insn-attr-x86.awk
  Makefile: set LC_CTYPE, LC_COLLATE, LC_NUMERIC to C
  x86: Increase MAX_EARLY_RES; insufficient on 32-bit NUMA
  x86: Fix checking of SRAT when node 0 ram is not from 0
  x86, cpuid: Add "volatile" to asm in native_cpuid()
  x86, msr: msrs_alloc/free for CONFIG_SMP=n
  x86, amd: Get multi-node CPU info from NodeId MSR instead of PCI config space
  x86: Add IA32_TSC_AUX MSR and use it
  x86, msr/cpuid: Register enough minors for the MSR and CPUID drivers
  initramfs: add missing decompressor error check
  bzip2: Add missing checks for malloc returning NULL
  bzip2/lzma/gzip: pre-boot malloc doesn't return NULL on failure

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

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (25 commits)
  sched: Fix broken assertion
  sched: Assert task state bits at build time
  sched: Update task_state_arraypwith new states
  sched: Add missing state chars to TASK_STATE_TO_CHAR_STR
  sched: Move TASK_STATE_TO_CHAR_STR near the TASK_state bits
  sched: Teach might_sleep() about preemptible RCU
  sched: Make warning less noisy
  sched: Simplify set_task_cpu()
  sched: Remove the cfs_rq dependency from set_task_cpu()
  sched: Add pre and post wakeup hooks
  sched: Move kthread_bind() back to kthread.c
  sched: Fix select_task_rq() vs hotplug issues
  sched: Fix sched_exec() balancing
  sched: Ensure set_task_cpu() is never called on blocked tasks
  sched: Use TASK_WAKING for fork wakups
  sched: Select_task_rq_fair() must honour SD_LOAD_BALANCE
  sched: Fix task_hot() test order
  sched: Fix set_cpu_active() in cpu_down()
  sched: Mark boot-cpu active before smp_init()
  sched: Fix cpu_clock() in NMIs, on !CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
  ...

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

* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sys: Fix missing rcu protection for __task_cred() access
  signals: Fix more rcu assumptions
  signal: Fix racy access to __task_cred in kill_pid_info_as_uid()

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

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  timers: Remove duplicate setting of new_base in __mod_timer()
  clockevents: Prevent clockevent_devices list corruption on cpu hotplug

* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
  [S390] Use strim instead of strstrip to avoid false warnings.
  [S390] qdio: add counter for input queue full condition
  [S390] qdio: remove superfluous log entries and WARN_ONs.
  [S390] ptrace: dont abuse PT_PTRACED
  [S390] cio: fix channel path vary
  [S390] drivers: Correct size given to memset
  [S390] tape: Add pr_fmt() macro to all tape source files
  [S390] rename NT_PRXSTATUS to NT_S390_HIGHREGS
  [S390] tty: PTR_ERR return of wrong pointer in fs3270_open()
  [S390] s390: PTR_ERR return of wrong pointer in fallback_init_cip()
  [S390] dasd: PTR_ERR return of wrong pointer in
  [S390] dasd: move dasd-diag kmsg to dasd
  [S390] cio: fix drvdata usage for the console subchannel
  [S390] wire up sys_recvmmsg

Several leaks in audit_tree didn't get caught by commit
318b6d3d, including the leak on normal
exit in case of multiple rules refering to the same chunk.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

... aka "Al had badly fscked up when writing that thing and nobody
noticed until Eric had fixed leaks that used to mask the breakage".

The function essentially creates a copy of old array sans one element
and replaces the references to elements of original (they are on cyclic
lists) with those to corresponding elements of new one.  After that the
old one is fair game for freeing.

First of all, there's a dumb braino: when we get to list_replace_init we
use indices for wrong arrays - position in new one with the old array
and vice versa.

Another bug is more subtle - termination condition is wrong if the
element to be excluded happens to be the last one.  We shouldn't go
until we fill the new array, we should go until we'd finished the old
one.  Otherwise the element we are trying to kill will remain on the
cyclic lists...

That crap used to be masked by several leaks, so it was not quite
trivial to hit.  Eric had fixed some of those leaks a while ago and the
shit had hit the fan...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Update to the new cs5535_mfgpt* API.  The geode-specific wording should
eventually be dropped from this driver...
Signed-off-by: Andres Salomon <dilinger@collabora.co.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Add a counter to the qdio performance statistics that indicates that no
free buffers were left in the input queue. If the counter gets increased
it means that the qdio adapter filled all available buffers and possibly
had more buffers ready but could not transmit them.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

* Don't write debug feature log entries for sl, slsb and sbal since these
  elements can be located from the qdio_q pointer which is also logged.
* Convert WARN_ON for wrong alignment of sbal to BUG_ON.
* Remove WARN_ON's for wrong alignment of q / qib / slib since these
  alignments should be guaranteed by kmem_cache_alloc alignment /
  struct aligned attribute / __get_free_page.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Nobody except ptrace itself should use task->ptrace or PT_PTRACED
directly, change arch/s390/kernel/traps.c to use the helper.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Channel path vary is currently broken: channel paths which are varied
offline are still used by Linux. The reason for this is that:

 * the path mask indicating which paths of an I/O device can be used
   is reset by each internal I/O request
 * the logic that checks if a path group is already in its designated
   target state incorrectly interprets the result "is correctly set"
   as "is correctly set and available"

Fix this by resetting the path mask only for internal I/O requests
which affect the path mask and by correcting the pgid check logic.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Memset should be given the size of the structure, not the size of the pointer.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
type T;
T *x;
expression E;
@@

memset(x, E, sizeof(
+ *
 x))
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Without defining the pr_fmt() macro, the "tape: " prefix will not be
printed when using the pr_xxx printk macros. This patch adds the
missing definitions.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

The elf notes number for the upper register halves is s390 specific.
Change the name of the elf notes to include S390.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Return the PTR_ERR of the correct pointer.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Return the PTR_ERR of the correct pointer.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Return the PTR_ERR of the correct pointer.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

The DIAG discipline does not have a own driver name. It shows up as
dasd-eckd or dasd-fba. So messages for dasd-diag are moved to the
generic dasd part.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Using dev_set_drvdata prior to device_register will force the driver core
to kmalloc its private data. Since we use this for the console subchannel
lets set the drvdata before taking the subchannels spinlock.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

John Blackwood reported:
> on an older Dell PowerEdge 6650 system with 8 cpus (4 are hyper-threaded),
> and  32 bit (x86) kernel, once you change the irq smp_affinity of an irq
> to be less than all cpus in the system, you can never change really the
> irq smp_affinity back to be all cpus in the system (0xff) again,
> even though no error status is returned on the "/bin/echo ff >
> /proc/irq/[n]/smp_affinity" operation.
>
> This is due to that fact that BAD_APICID has the same value as
> all cpus (0xff) on 32bit kernels, and thus the value returned from
> set_desc_affinity() via the cpu_mask_to_apicid_and() function is treated
> as a failure in set_ioapic_affinity_irq_desc(), and no affinity changes
> are made.

set_desc_affinity() is already checking if the incoming cpu mask
intersects with the cpu online mask or not. So there is no need
for the apic op cpu_mask_to_apicid_and() to check again
and return BAD_APICID.

Remove the BAD_APICID return value from cpu_mask_to_apicid_and()
and also fix set_desc_affinity() to return -1 instead of using BAD_APICID
to represent error conditions (as cpu_mask_to_apicid_and() can return
logical or physical apicid values and BAD_APICID is really to represent
bad physical apic id).
Reported-by: John Blackwood <john.blackwood@ccur.com>
Root-caused-by: John Blackwood <john.blackwood@ccur.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1261103386.2535.409.camel@sbs-t61>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Merge branch 'cpumask-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus

* 'cpumask-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  cpumask: rename tsk_cpumask to tsk_cpus_allowed
  cpumask: don't recommend set_cpus_allowed hack in Documentation/cpu-hotplug.txt
  cpumask: avoid dereferencing struct cpumask
  cpumask: convert drivers/idle/i7300_idle.c to cpumask_var_t
  cpumask: use modern cpumask style in drivers/scsi/fcoe/fcoe.c
  cpumask: avoid deprecated function in mm/slab.c
  cpumask: use cpu_online in kernel/perf_event.c

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:
  Keys: KEYCTL_SESSION_TO_PARENT needs TIF_NOTIFY_RESUME architecture support
  NOMMU: Optimise away the {dac_,}mmap_min_addr tests
  security/min_addr.c: make init_mmap_min_addr() static
  keys: PTR_ERR return of wrong pointer in keyctl_get_security()

Merge branch 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6

* 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6:
  OMAP3: serial - fix bug introduced in
  mfd: twl: fix twl4030 rename for remaining driver, board files
  USB ehci: replace mach header with plat
  omap3: Allow EHCI to be built on OMAP3

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  hwmon: (w83627hf) Fix for "No such device"
  hwmon: (sht15) Off-by-one error in array index + incorrect constants
  hwmon: Add driver for VIA CPU core temperature
  hwmon: (smsc47m1) Enable device if needed
  hwmon: (smsc47m1) Fail module loading on error
  hwmon: (smsc47m1) Only request I/O ports we really use
  hwmon: New driver for AMD Family 10h/11h CPUs

* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (40 commits)
  [SCSI] 3w-9xxx fix bug in sgl loading
  [SCSI] fcoe, libfc: adds enable/disable for fcoe interface
  [SCSI] libfc: reduce hold time on SCSI host lock
  [SCSI] libfc: remote port gets stuck in restart state without really restarting
  [SCSI] pm8001: misc code cleanup
  [SCSI] pm8001: enable read HBA SAS address from VPD
  [SCSI] pm8001: do not reset local sata as it will not be found if reset
  [SCSI] pm8001: bit set pm8001_ha->flags
  [SCSI] pm8001:fix potential NULL pointer dereference
  [SCSI] pm8001: set SSC down-spreading only to get less errors on some 6G device.
  [SCSI] pm8001: fix endian issues with SAS address
  [SCSI] pm8001: enhance error handle for IO patch
  [SCSI] pm8001: Fix for sata io circular lock dependency.
  [SCSI] hpsa: add driver for HP Smart Array controllers.
  [SCSI] cxgb3i: always use negative errno in case of error
  [SCSI] bnx2i: minor code cleanup and update driver version
  [SCSI] bnx2i: Task management ABORT TASK fixes
  [SCSI] bnx2i: update CQ arming algorith for 5771x chipsets
  [SCSI] bnx2i: Adjust sq_size module parametr to power of 2 only if a non-zero value is specified
  [SCSI] bnx2i: Add 5771E device support to bnx2i driver
  ...

* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (71 commits)
  MIPS: Lasat: Fix botched changes to sysctl code.
  RTC: rtc-cmos.c: Fix warning on MIPS
  MIPS: Cleanup random differences beween lmo and Linus' kernel.
  MIPS: No longer hardwire CONFIG_EMBEDDED to y
  MIPS: Fix and enhance built-in kernel command line
  MIPS: eXcite: Remove platform.
  MIPS: Loongson: Cleanups of serial port support
  MIPS: Lemote 2F: Suspend CS5536 MFGPT Timer
  MIPS: Excite: move iodev_remove to .devexit.text
  MIPS: Lasat: Convert to proc_fops / seq_file
  MIPS: Cleanup signal code initialization
  MIPS: Modularize COP2 handling
  MIPS: Move EARLY_PRINTK to Kconfig.debug
  MIPS: Yeeloong 2F: Cleanup reset logic using the new ec_write function
  MIPS: Yeeloong 2F: Add LID open event as the wakeup event
  MIPS: Yeeloong 2F: Add basic EC operations
  MIPS: Move several variables from .bss to .init.data
  MIPS: Tracing: Make function graph tracer work with -mmcount-ra-address
  MIPS: Tracing: Reserve $12(t0) for mcount-ra-address of gcc 4.5
  MIPS: Tracing: Make ftrace for MIPS work without -fno-omit-frame-pointer
  ...

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: make sure fallocate properly starts a transaction
  Btrfs: make metadata chunks smaller
  Btrfs: Show discard option in /proc/mounts
  Btrfs: deny sys_link across subvolumes.
  Btrfs: fail mount on bad mount options
  Btrfs: don't add extent 0 to the free space cache v2
  Btrfs: Fix per root used space accounting
  Btrfs: Fix btrfs_drop_extent_cache for skip pinned case
  Btrfs: Add delayed iput
  Btrfs: Pass transaction handle to security and ACL initialization functions
  Btrfs: Make truncate(2) more ENOSPC friendly
  Btrfs: Make fallocate(2) more ENOSPC friendly
  Btrfs: Avoid orphan inodes cleanup during committing transaction
  Btrfs: Avoid orphan inodes cleanup while replaying log
  Btrfs: Fix disk_i_size update corner case
  Btrfs: Rewrite btrfs_drop_extents
  Btrfs: Add btrfs_duplicate_item
  Btrfs: Avoid superfluous tree-log writeout

* 'kmemleak' of git://linux-arm.org/linux-2.6:
  kmemleak: fix kconfig for crc32 build error
  kmemleak: Reduce the false positives by checking for modified objects
  kmemleak: Show the age of an unreferenced object
  kmemleak: Release the object lock before calling put_object()
  kmemleak: Scan the _ftrace_events section in modules
  kmemleak: Simplify the kmemleak_scan_area() function prototype
  kmemleak: Do not use off-slab management with SLAB_NOLEAKTRACE

* 'next-spi' of git://git.secretlab.ca/git/linux-2.6:
  spi: spi_txx9.c: use resource_size()
  spi: spi_sh_sci.c: use resource_size()
  spi: spi_mpc8xxx.c: use resource_size()
  spi: spi_bfin5xx.c: use resource_size()
  spi: atmel_spi.c: use resource_size()
  spi: Add s3c64xx SPI Controller driver
  atmel_spi: fix dma addr calculation for len > BUFFER_SIZE
  spi_s3c24xx: add FIQ pseudo-DMA support
  spi: controller driver for Designware SPI core
  spidev: add proper section markers
  spidev: use DECLARE_BITMAP instead of declaring the array

* 'for-linus' of git://git.o-hand.com/linux-rpurdie-backlight:
  backlight: mbp_nvidia_bl - add two more MacBookPro variants
  backlight: Pass device through notify callback in the pwm driver
  backlight: PTR_ERR return of wrong pointer in cr_backlight_probe()
  backlight: Constify struct backlight_ops
  backlight/thinkpad-acpi: issue backlight class events

Fix up trivial conflicts in thinkpad-acpi support (backlight support
already merged earlier).

* 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds:
  leds: leds-pwm: Set led_classdev max_brightness
  leds: leds-lp3944.h - remove unneeded includes
  leds: use default-on trigger for Cobalt Qube
  leds: drivers/leds/leds-ss4200.c: fix return statement
  leds: leds-pca9532.h- indent with tabs, not spaces
  leds: Add LED class driver for regulator driven LEDs.
  leds: leds-cobalt-qube.c: use resource_size()
  leds: leds-cobalt-raq.c - use resource_size()
  leds: Add driver for ADP5520/ADP5501 MFD PMICs
  leds: Add driver for LT3593 controlled LEDs
  leds-ss4200: Check pci_enable_device return
  leds: leds-alix2c - take port address from MSR
  leds: LED driver for Intel NAS SS4200 series (v5)

* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm:
  PCMCIA: fix pxa2xx_lubbock modular build error
  [ARM] Update mach-types
  [ARM] pxa: fix no reference of cpu_is_pxa25x() in devices.c
  [ARM] pxa/cm-x300: add PWM backlight support
  revert "[ARM] pxa/cm-x300: add PWM backlight support"
  ARM: use flush_kernel_dcache_area() for dmabounce
  ARM: add size argument to __cpuc_flush_dcache_page
  ARM: 5848/1: kill flush_ioremap_region()
  ARM: cache-l2x0: make better use of background cache handling
  ARM: cache-l2x0: avoid taking spinlock for every iteration
  [ARM] Kirkwood: Add LaCie Network Space v2 support
  ARM: dove: fix the mm mmu flags of the pj4 procinfo

Apparently not all versions of glibc and utilities treat an empty
LC_ALL as nonexistent, causing error messages to be garbled.  Instead,
explicitly unexport it from the environment.
Reported-and-tested-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
LKML-Reference: <4B2AC394.4030108@redhat.com>
Cc: Michal Marek <mmarek@sues.cz>
Cc: Roland Dreier <rdreier@cisco.com>
Cc: Sam Ravnborg <sam@ravnborg.org>

Fix kernel-doc warnings in printk.c:

Warning(kernel/printk.c:1422): No description found for parameter 'dumper'
Warning(kernel/printk.c:1422): Excess function parameter 'dump' description in 'kmsg_dump_register'
Warning(kernel/printk.c:1451): No description found for parameter 'dumper'
Warning(kernel/printk.c:1451): Excess function parameter 'dump' description in 'kmsg_dump_unregister'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

I added blk_run_backing_dev on page_cache_async_readahead so readahead I/O
is unpluged to improve throughput on especially RAID environment.

The normal case is, if page N become uptodate at time T(N), then T(N) <=
T(N+1) holds.  With RAID (and NFS to some degree), there is no strict
ordering, the data arrival time depends on runtime status of individual
disks, which breaks that formula.  So in do_generic_file_read(), just
after submitting the async readahead IO request, the current page may well
be uptodate, so the page won't be locked, and the block device won't be
implicitly unplugged:

               if (PageReadahead(page))
                        page_cache_async_readahead()
                if (!PageUptodate(page))
                                goto page_not_up_to_date;
                //...
page_not_up_to_date:
                lock_page_killable(page);

Therefore explicit unplugging can help.

Following is the test result with dd.

#dd if=testdir/testfile of=/dev/null bs=16384

-2.6.30-rc6
1048576+0 records in
1048576+0 records out
17179869184 bytes (17 GB) copied, 224.182 seconds, 76.6 MB/s

-2.6.30-rc6-patched
1048576+0 records in
1048576+0 records out
17179869184 bytes (17 GB) copied, 206.465 seconds, 83.2 MB/s

(7Disks RAID-0 Array)

-2.6.30-rc6
1054976+0 records in
1054976+0 records out
17284726784 bytes (17 GB) copied, 212.233 seconds, 81.4 MB/s

-2.6.30-rc6-patched
1054976+0 records out
17284726784 bytes (17 GB) copied, 198.878 seconds, 86.9 MB/s

(7Disks RAID-5 Array)

The patch was found to improve performance with the SCST scsi target
driver.  See
http://sourceforge.net/mailarchive/forum.php?thread_name=a0272b440906030714g67eabc5k8f847fb1e538cc62%40mail.gmail.com&forum_name=scst-devel

[akpm@linux-foundation.org: unbust comment layout]
[akpm@linux-foundation.org: "fix" CONFIG_BLOCK=n]
Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
Acked-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Tested-by: Ronald <intercommit@gmail.com>
Cc: Bart Van Assche <bart.vanassche@gmail.com>
Cc: Vladislav Bolkhovitin <vst@vlnb.net>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

RTC core won't allow wakeup alarms to be set if RTC devices' parent (i.e.
i2c_client or spi_device) isn't wakeup capable.

For I2C devices there is I2C_CLIENT_WAKE flag exists that we can pass via
board info, and if set, I2C core will initialize wakeup capability.  For
SPI devices there is no such flag at all.

I believe that it's not platform code responsibility to allow or disallow
wakeups, instead, drivers themselves should set the capability if a device
can trigger wakeups.

That's what drivers/base/power/sysfs.c says:

 * It is the responsibility of device drivers to enable (or disable)
 * wakeup signaling as part of changing device power states, respecting
 * the policy choices provided through the driver model.

I2C and SPI RTC devices send wakeup events via interrupt lines, so we
should set the wakeup capability if IRQ is routed.

Ideally we should also check irq for wakeup capability before setting
device's capability, i.e.

	if (can_irq_wake(irq))
		device_set_wakeup_capable(&client->dev, 1);

But there is no can_irq_wake() call exist, and it is not that trivial to
implement it for all interrupts controllers and complex/cascaded setups.

drivers/base/power/sysfs.c also covers these cases:

 * Devices may not be able to generate wakeup events from all power
 * states.  Also, the events may be ignored in some configurations;
 * for example, they might need help from other devices that aren't
 * active

So there is no guarantee that wakeup will actually work, and so I think
there is no point in being pedantic wrt checking IRQ wakeup capability.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>