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Commit Graph

514 Commits

Author SHA1 Message Date
Linus Torvalds
517d08699b Merge branch 'akpm'
* akpm: (182 commits)
  fbdev: bf54x-lq043fb: use kzalloc over kmalloc/memset
  fbdev: *bfin*: fix __dev{init,exit} markings
  fbdev: *bfin*: drop unnecessary calls to memset
  fbdev: bfin-t350mcqb-fb: drop unused local variables
  fbdev: blackfin has __raw I/O accessors, so use them in fb.h
  fbdev: s1d13xxxfb: add accelerated bitblt functions
  tcx: use standard fields for framebuffer physical address and length
  fbdev: add support for handoff from firmware to hw framebuffers
  intelfb: fix a bug when changing video timing
  fbdev: use framebuffer_release() for freeing fb_info structures
  radeon: P2G2CLK_ALWAYS_ONb tested twice, should 2nd be P2G2CLK_DAC_ALWAYS_ONb?
  s3c-fb: CPUFREQ frequency scaling support
  s3c-fb: fix resource releasing on error during probing
  carminefb: fix possible access beyond end of carmine_modedb[]
  acornfb: remove fb_mmap function
  mb862xxfb: use CONFIG_OF instead of CONFIG_PPC_OF
  mb862xxfb: restrict compliation of platform driver to PPC
  Samsung SoC Framebuffer driver: add Alpha Channel support
  atmel-lcdc: fix pixclock upper bound detection
  offb: use framebuffer_alloc() to allocate fb_info struct
  ...

Manually fix up conflicts due to kmemcheck in mm/slab.c
2009-06-16 19:50:13 -07:00
Alexey Dobriyan
bb1f17b037 mm: consolidate init_mm definition
* create mm/init-mm.c, move init_mm there
* remove INIT_MM, initialize init_mm with C99 initializer
* unexport init_mm on all arches:

  init_mm is already unexported on x86.

  One strange place is some OMAP driver (drivers/video/omap/) which
  won't build modular, but it's already wants get_vm_area() export.
  Somebody should look there.

[akpm@linux-foundation.org: add missing #includes]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Cc: Americo Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-16 19:47:28 -07:00
David S. Miller
d1ae4ce3d0 sparc: Wire up sys_rt_tgsigqueueinfo().
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:58 -07:00
Stephen Rothwell
6ac5c61082 sparc: replace uses of CPU_MASK_ALL_PTR
CPU_MASK_ALL is the (deprecated) "all bits set" cpumask, defined as so:

	#define CPU_MASK_ALL (cpumask_t) { { ... } }

Taking the address of such a temporary is questionable at best,
unfortunately 321a8e9d (cpumask: add CPU_MASK_ALL_PTR macro) added
CPU_MASK_ALL_PTR:

	#define CPU_MASK_ALL_PTR (&CPU_MASK_ALL)

Which formalizes this practice.  One day gcc could bite us over this
usage (though we seem to have gotten away with it so far).

[Description by Rusty Russell]
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:55 -07:00
David S. Miller
9be12f9b1c sparc64: Add proper dynamic ftrace support.
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
2009-06-16 04:56:53 -07:00
Robert Reif
c9f5b7e77c sparc: move of_device common code to of_device_common
This patch moves code common to of_device_32.c and of_device_64.c into
of_device_common.h and of_device_common.c.

The only functional difference is in sparc32 where of_bus_default_map is
used in place of of_bus_sbus_map because they are equivelent.

There is still room for further code consolidation with some minor
refactoring.

Boot tested on sparc32 and compile tested on sparc64.

Signed-off-by: Robert Reif <reif@earthlink.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:49 -07:00
FUJITA Tomonori
d69864158e sparc: remove dma-mapping_{32|64}.h
This modifies SPARC32 to use struct dma_map ops. It means that we can
remove dma-mapping_{32|64}.h.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: Robert Reif <reif@earthlink.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:47 -07:00
FUJITA Tomonori
797a756865 sparc: use dma_map_page instead of dma_map_single
This patch converts dma_map_single and dma_unmap_single to use
map_page and unmap_page respectively and removes unnecessary
map_single and unmap_single. map_page can be used to implement
map_single but the opposite is impossible. Having only dma_map_page in
struct dma_ops is enough.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: Robert Reif <reif@earthlink.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:45 -07:00
FUJITA Tomonori
b9f69f4f4a sparc: move the duplication in dma-mapping_{32|64}.h to dma-mapping.h
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: Robert Reif <reif@earthlink.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:41 -07:00
Hong H. Pham
280ff97494 sparc64: fix and optimize irq distribution
irq_choose_cpu() should compare the affinity mask against cpu_online_map
rather than CPU_MASK_ALL, since irq_select_affinity() sets the interrupt's
affinity mask to cpu_online_map "and" CPU_MASK_ALL (which ends up being
just cpu_online_map).  The mask comparison in irq_choose_cpu() will always
fail since the two masks are not the same.  So the CPU chosen is the first CPU
in the intersection of cpu_online_map and CPU_MASK_ALL, which is always CPU0.
That means all interrupts are reassigned to CPU0...

Distributing interrupts to CPUs in a linearly increasing round robin fashion
is not optimal for the UltraSPARC T1/T2.  Also, the irq_rover in
irq_choose_cpu() causes an interrupt to be assigned to a different
processor each time the interrupt is allocated and released.  This may lead
to an unbalanced distribution over time.

A static mapping of interrupts to processors is done to optimize and balance
interrupt distribution.  For the T1/T2, interrupts are spread to different
cores first, and then to strands within a core.

The following is some benchmarks showing the effects of interrupt
distribution on a T2.  The test was done with iperf using a pair of T5220
boxes, each with a 10GBe NIU (XAUI) connected back to back.

  TCP     | Stock       Linear RR IRQ  Optimized IRQ
  Streams | 2.6.30-rc5  Distribution   Distribution
          | GBits/sec   GBits/sec      GBits/sec
  --------+-----------------------------------------
    1       0.839       0.862          0.868
    8       1.16        4.96           5.88
   16       1.15        6.40           8.04
  100       1.09        7.28           8.68

Signed-off-by: Hong H. Pham <hong.pham@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:28 -07:00
David S. Miller
4fd78a5f1e sparc64: Use new dynamic per-cpu allocator.
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:27 -07:00
David S. Miller
0c243ad81f sparc64: Only allocate per-cpu areas for possible cpus.
This gets us real close to the generic implementation of
setup_per_cpu_areas() except:

1) We store the per-cpu offset into the trap_block[], whereas
   the generic code has it's own static array.

2) We have to initialize the %g5 register to hold the boot cpu's
   per-cpu area offset.

3) The OBP/MDESC cpu info scan is performed at the end.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:25 -07:00
David S. Miller
73fffc037e sparc64: Get rid of real_setup_per_cpu_areas().
Now that we defer the cpu_data() initializations to the end of per-cpu
setup, we can get rid of this local hack we had to setup the per-cpu
areas eary.

This is a necessary step in order to support HAVE_DYNAMIC_PER_CPU_AREA
since the per-cpu setup must run when page structs are available.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:23 -07:00
David S. Miller
b696fdc259 sparc64: Defer cpu_data() setup until end of per-cpu data initialization.
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:22 -07:00
David S. Miller
a2094502dc sparc64: Make mdesc_fill_in_cpu_data take a cpumask_t pointer.
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:21 -07:00
David S. Miller
890db403d5 sparc: Call OF and MD cpu scanning explicitly from paging_init()
We need to split up the cpu present mask setup from the cpu_data
initialization, and this is a first step towards that.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:19 -07:00
David S. Miller
5052f525fd sparc64: Refactor MDESC cpu scanning code using an iterator.
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:17 -07:00
David S. Miller
9bab54143c sparc64: Refactor OBP cpu scanning code using an iterator.
With feedback from Sam Ravnborg.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:16 -07:00
David S. Miller
8249778908 sparc64: Use BUILD_BUG_ON() in trap_init().
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:13 -07:00
David S. Miller
5a5488d3bb sparc64: Store per-cpu offset in trap_block[]
Surprisingly this actually makes LOAD_PER_CPU_BASE() a little
more efficient.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:11 -07:00
David S. Miller
557fe0e884 sparc64: Reclaim trap_block[]->hdesc
This really isn't necessary at all, a local variable suits the
job just fine.

This frees up 8 bytes in the trap_block[] that we can use later
to store the per-cpu base addresses.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-16 04:56:08 -07:00
Rusty Russell
5933048c69 module: cleanup FIXME comments about trimming exception table entries.
Everyone cut and paste this comment from my original one.  We now do
it generically, so cut the comments.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Amerigo Wang <amwang@redhat.com>
2009-06-12 21:47:05 +09:30
Ingo Molnar
6cda3eb62e Merge branch 'x86/apic' into irq/numa
Merge reason: both topics modify the APIC code but were able to do it in
              parallel so far. An upcoming patch generates a conflict so
              merge them to avoid the conflict.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-12 12:17:36 +02:00
Yinghai Lu
d5dedd4507 irq: change ->set_affinity() to return status
according to Ingo, change set_affinity() in irq_chip should return int,
because that way we can handle failure cases in a much cleaner way, in
the genirq layer.

v2: fix two typos

[ Impact: extend API ]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: linux-arch@vger.kernel.org
LKML-Reference: <49F654E9.4070809@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-28 12:21:16 +02:00
Tim Abbott
a0871e8cb8 sparc: cleanup references to deprecated .text.init* sections.
The section .text.init.refok is deprecated and __REF (.ref.text)
should be used in assembly files instead.  This patch cleans up a few
uses of .text.init.refok in the sparc architecture.

Also fix a reference to .text.init in a comment that wasn't updated to
.init.text.

Signed-off-by: Tim Abbott <tabbott@mit.edu>
Cc: David S. Miller <davem@davemloft.net>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-27 19:51:58 -07:00
Tim Abbott
ce8a7424d2 sparc: convert to use __HEAD and HEAD_TEXT macros.
This has the consequence of changing the section name use for head
code from ".text.head" to ".head.text".  Since this commit changes all
users in the architecture, this change should be harmless.

Signed-off-by: Tim Abbott <tabbott@mit.edu>
Cc: David S. Miller <davem@davemloft.net>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-26 09:20:39 -07:00
Linus Torvalds
dc0046c758 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc: Fix bus type probing for ESP and LE devices.
  sparc32: Update defconfig.
  sparc64: Update defconfig.
2009-04-24 07:45:52 -07:00
David S. Miller
956d039a25 sparc: Fix bus type probing for ESP and LE devices.
If there is a dummy "espdma" or "ledma" parent device above ESP scsi
or LE ethernet device nodes, we have to match the bus as SBUS.

Otherwise the address and size cell counts are wrong and we don't
calculate the final physical device resource values correctly at all.

Commit 5280267c1d ("sparc: Fix handling
of LANCE and ESP parent nodes in of_device.c") was meant to fix this
problem, but that only influences the inner loop of
build_device_resources().  We need this logic to also kick in at the
beginning of build_device_resources() as well, when we make the first
attempt to determine the device's immediate parent bus type for 'reg'
property element extraction.

Based almost entirely upon a patch by Friedrich Oslage.

Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-22 03:46:14 -07:00
Magnus Damm
8e19608e8b clocksource: pass clocksource to read() callback
Pass clocksource pointer to the read() callback for clocksources.  This
allows us to share the callback between multiple instances.

[hugh@veritas.com: fix powerpc build of clocksource pass clocksource mods]
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 13:41:47 -07:00
Oleg Drokin
0112fc2229 Separate out common fstatat code into vfs_fstatat
This is a version incorporating Christoph's suggestion.

Separate out common *fstatat functionality into a single function
instead of duplicating it all over the code.

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-20 23:02:51 -04:00
Wei Yongjun
ed247e12fe sparc: remove some pointless conditionals before kfree()
Remove some pointless conditionals before kfree().

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-15 03:04:56 -07:00
David S. Miller
8e255baa44 sparc64: Fix smp_callin() locking.
Interrupts must be disabled when taking the IPI lock.

Caught by lockdep.

Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-14 17:08:56 -07:00
David S. Miller
018ef96969 sparc: Hook up sys_preadv and sys_pwritev
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-08 03:55:30 -07:00
David S. Miller
9a2ed5cc9e sparc64: Fix section mismatch warnings in PCI controller drivers.
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-08 03:28:15 -07:00
David S. Miller
19ab6db66c sparc64: Fix section mismatch warnings in power driver.
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-08 03:27:52 -07:00
David S. Miller
6bbc0b08db sparc64: get_cells() can't be marked __init
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-08 03:27:38 -07:00
Linus Torvalds
811158b147 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (28 commits)
  trivial: Update my email address
  trivial: NULL noise: drivers/mtd/tests/mtd_*test.c
  trivial: NULL noise: drivers/media/dvb/frontends/drx397xD_fw.h
  trivial: Fix misspelling of "Celsius".
  trivial: remove unused variable 'path' in alloc_file()
  trivial: fix a pdlfush -> pdflush typo in comment
  trivial: jbd header comment typo fix for JBD_PARANOID_IOFAIL
  trivial: wusb: Storage class should be before const qualifier
  trivial: drivers/char/bsr.c: Storage class should be before const qualifier
  trivial: h8300: Storage class should be before const qualifier
  trivial: fix where cgroup documentation is not correctly referred to
  trivial: Give the right path in Documentation example
  trivial: MTD: remove EOL from MODULE_DESCRIPTION
  trivial: Fix typo in bio_split()'s documentation
  trivial: PWM: fix of #endif comment
  trivial: fix typos/grammar errors in Kconfig texts
  trivial: Fix misspelling of firmware
  trivial: cgroups: documentation typo and spelling corrections
  trivial: Update contact info for Jochen Hein
  trivial: fix typo "resgister" -> "register"
  ...
2009-04-03 15:24:35 -07:00
Alexey Dobriyan
6f2c55b843 Simplify copy_thread()
First argument unused since 2.3.11.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:04:51 -07:00
Linus Torvalds
d3d52d687a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc64: Fix reset hangs on Niagara systems.
  cpumask: use mm_cpumask() wrapper: sparc
  cpumask: remove dangerous CPU_MASK_ALL_PTR, &CPU_MASK_ALL.: sparc
  cpumask: remove the now-obsoleted pcibus_to_cpumask(): sparc
  cpumask: remove cpu_coregroup_map: sparc
  cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits.: sparc
  cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits.: sparc64
  cpumask: Use accessors code.: sparc64
  cpumask: Use accessors code: sparc
  cpumask: arch_send_call_function_ipi_mask: sparc
  cpumask: Use smp_call_function_many(): sparc64
2009-03-30 18:46:12 -07:00
Linus Torvalds
d17abcd541 Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask:
  oprofile: Thou shalt not call __exit functions from __init functions
  cpumask: remove the now-obsoleted pcibus_to_cpumask(): generic
  cpumask: remove cpumask_t from core
  cpumask: convert rcutorture.c
  cpumask: use new cpumask_ functions in core code.
  cpumask: remove references to struct irqaction's mask field.
  cpumask: use mm_cpumask() wrapper: kernel/fork.c
  cpumask: use set_cpu_active in init/main.c
  cpumask: remove node_to_first_cpu
  cpumask: fix seq_bitmap_*() functions.
  cpumask: remove dangerous CPU_MASK_ALL_PTR, &CPU_MASK_ALL
2009-03-30 18:00:26 -07:00
Alexey Dobriyan
99b7623380 proc 2/2: remove struct proc_dir_entry::owner
Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.

We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.

But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.

->read_proc/->write_proc were just fixed to not require ->owner for
protection.

rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.

Removing ->owner will also make PDE smaller.

So, let's nuke it.

Kudos to Jeff Layton for reminding about this, let's say, oversight.

http://bugzilla.kernel.org/show_bug.cgi?id=12454

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-03-31 01:14:44 +04:00
Nick Andrew
877d03105d trivial: Fix misspelling of firmware
Fix misspelling of firmware.

Signed-off-by: Nick Andrew <nick@nick-andrew.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-03-30 15:21:59 +02:00
Rusty Russell
1a8a51004a cpumask: remove references to struct irqaction's mask field.
Impact: cleanup

It's unused, since about 1995.  So remove all initialization of it in
preparation for actually removing the field.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
2009-03-30 22:05:14 +10:30
David S. Miller
ed223129a3 Merge branch 'master' of ssh://master.kernel.org/home/ftp/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask-for-sparc
Conflicts:
	arch/sparc/kernel/smp_64.c
2009-03-29 15:44:22 -07:00
David S. Miller
ffaba67409 sparc64: Fix reset hangs on Niagara systems.
Hypervisor versions older than version 1.6.1 cannot handle
leaving the profile counter overflow interrupt chirping
when the system does a soft reset.

So use a reboot notifier to shut off the NMI watchdog.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-29 15:40:33 -07:00
Ingo Molnar
82268da1b1 Merge branch 'linus' into percpu-cpumask-x86-for-linus-2
Conflicts:
	arch/sparc/kernel/time_64.c
	drivers/gpu/drm/drm_proc.c

Manual merge to resolve build warning due to phys_addr_t type change
on x86:

	drivers/gpu/drm/drm_info.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-28 04:26:01 +01:00
David S. Miller
6e8a4fa651 sparc64: We need to use compat_sys_ustat() as well.
Sparc was missed in commit 2b1c6bd77d
("generic compat_sys_ustat").  We definitely need it, since our
__kernel_ino_t is "unsigned long".

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-27 18:15:02 -07:00
David S. Miller
a83398570e Merge branch 'master' of /home/davem/src/GIT/linux-2.6/ 2009-03-27 17:19:16 -07:00
Ingo Molnar
6e15cf0486 Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2
Conflicts:
	arch/parisc/kernel/irq.c
	arch/x86/include/asm/fixmap_64.h
	arch/x86/include/asm/setup.h
	kernel/irq/handle.c

Semantic merge:
        arch/x86/include/asm/fixmap.h

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-27 17:28:43 +01:00
David S. Miller
f9384d41c0 sparc64: Fix MM refcount check in smp_flush_tlb_pending().
As explained by Benjamin Herrenschmidt:

> CPU 0 is running the context, task->mm == task->active_mm == your
> context. The CPU is in userspace happily churning things.
>
> CPU 1 used to run it, not anymore, it's now running fancyfsd which
> is a kernel thread, but current->active_mm still points to that
> same context.
>
> Because there's only one "real" user, mm_users is 1 (but mm_count is
> elevated, it's just that the presence on CPU 1 as active_mm has no
> effect on mm_count().
>
> At this point, fancyfsd decides to invalidate a mapping currently mapped
> by that context, for example because a networked file has changed
> remotely or something like that, using unmap_mapping_ranges().
>
> So CPU 1 goes into the zapping code, which eventually ends up calling
> flush_tlb_pending(). Your test will succeed, as current->active_mm is
> indeed the target mm for the flush, and mm_users is indeed 1. So you
> will -not- send an IPI to the other CPU, and CPU 0 will continue happily
> accessing the pages that should have been unmapped.

To fix this problem, check ->mm instead of ->active_mm, and this
means:

> So if you test current->mm, you effectively account for mm_users == 1,
> so the only way the mm can be active on another processor is as a lazy
> mm for a kernel thread. So your test should work properly as long
> as you don't have a HW that will do speculative TLB reloads into the
> TLB on that other CPU (and even if you do, you flush-on-switch-in should
> get rid of any crap here).

And therefore we should be OK.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-27 01:09:17 -07:00