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322659 Commits

Author SHA1 Message Date
Linus Torvalds f4673d6f18 UBIFS fixes for 3.6:
1. Fix crash on error which prevents emulated power-cut testing.
 2. Fix log reply regression introduced in 3.6-rc1.
 3. Fix UBIFS complaints about too small debug buffer size which.
 4. Fix error message spelling, and remove incorrect commentary.
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Merge tag 'upstream-3.6-rc3' of git://git.infradead.org/linux-ubifs

Pull UBIFS fixes from Artem Bityutskiy:
 - Fix crash on error which prevents emulated power-cut testing.
 - Fix log reply regression introduced in 3.6-rc1.
 - Fix UBIFS complaints about too small debug buffer size which.
 - Fix error message spelling, and remove incorrect commentary.

* tag 'upstream-3.6-rc3' of git://git.infradead.org/linux-ubifs:
  UBIFS: fix error messages spelling
  UBIFS: fix complaints about too small debug buffer size
  UBIFS: fix replay regression
  UBIFS: fix crash on error path
  UBIFS: remove stale commentary
2012-08-23 21:50:40 -07:00
Linus Torvalds 270868f6e6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide
Pull IDE power management bugfix from David S. Miller.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide:
  ide: fix generic_ide_suspend/resume Oops
2012-08-23 21:49:56 -07:00
Linus Torvalds 7ca63ee1b0 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "This tree contains misc fixlets: a perf script python binding fix, a
  uprobes fix and a syscall tracing fix."

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tools: Add missing files to build the python binding
  uprobes: Fix mmap_region()'s mm->mm_rb corruption if uprobe_mmap() fails
  tracing/syscalls: Fix perf syscall tracing when syscall_nr == -1
2012-08-23 21:48:41 -07:00
Linus Torvalds caf1aaf6d2 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "This tree contains assorted fixlets: an alternatives patching crash
  fix, an irq migration/hotplug interaction fix, a fix for large AMD
  microcode images and a comment fixlet."

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, microcode, AMD: Fix broken ucode patch size check
  x86/alternatives: Fix p6 nops on non-modular kernels
  x86/fixup_irq: Use cpu_online_mask instead of cpu_all_mask
  x86/spinlocks: Fix comment in spinlock.h
2012-08-23 21:47:54 -07:00
Linus Torvalds b5bc0c7054 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "Mostly small fixes for the fallout of the timekeeping overhaul in 3.6
  along with stable fixes to address an accumulation problem and missing
  sanity checks for RTC readouts and user space provided values."

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Avoid making adjustments if we haven't accumulated anything
  time: Avoid potential shift overflow with large shift values
  time: Fix casting issue in timekeeping_forward_now
  time: Ensure we normalize the timekeeper in tk_xtime_add
  time: Improve sanity checking of timekeeping inputs
2012-08-23 21:46:57 -07:00
Linus Torvalds d37e44969e Merge branch 'upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
Pull HID fix from Jiri Kosina:
 "Fix for one particular device not being properly claimed by
  hid-multitouch driver"

* 'upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  HID: Remove QUANTA from special drivers list
2012-08-23 21:45:54 -07:00
Ben Hutchings ac70b2e9a1 sfc: Fix reporting of IPv4 full filters through ethtool
ETHTOOL_GRXCLSRULE returns filters for a TCP/IPv4 or UDP/IPv4 4-tuple
with source and destination swapped.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-08-24 04:17:21 +01:00
Jakob Bornecrantz 7c4eaca416 drm: Check for invalid cursor flags
Signed-off-by: Jakob Bornecrantz <jakob@vmware.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-08-24 09:38:40 +10:00
Ville Syrjälä 22f5d115a2 drm: Initialize object type when using DRM_MODE() macro
DRM_MODE() macro doesn't initialize the type of the base drm object.
When a copy is made of the mode, the object type is overwritten with
zero, and the the object can no longer be found by
drm_mode_object_find() due to the type check failing.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-08-24 09:38:31 +10:00
Tomas Racek a672e1be30 xfs: check for possible overflow in xfs_ioc_trim
If range.start or range.minlen is bigger than filesystem size, return
invalid value error. This fixes possible overflow in BTOBB macro when
passed value was nearly ULLONG_MAX.

Signed-off-by: Tomas Racek <tracek@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-08-23 14:48:44 -05:00
Christoph Hellwig 7612903099 xfs: unlock the AGI buffer when looping in xfs_dialloc
Also update some commens in the area to make the code easier to read.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-08-23 14:48:32 -05:00
Dave Chinner 0b9e3f6d84 xfs: fix uninitialised variable in xfs_rtbuf_get()
Results in this assert failure in generic/090:

XFS: Assertion failed: *nmap >= 1, file: fs/xfs/xfs_bmap.c, line: 4363
.....
Call Trace:
 [<ffffffff814680db>] xfs_bmapi_read+0x6b/0x370
 [<ffffffff814b64b2>] xfs_rtbuf_get+0x42/0x130
 [<ffffffff814b6f09>] xfs_rtget_summary+0x89/0x120
 [<ffffffff814b7bfe>] xfs_rtallocate_extent_size+0xce/0x340
 [<ffffffff814b89f0>] xfs_rtallocate_extent+0x240/0x290
 [<ffffffff81462c1a>] xfs_bmap_rtalloc+0x1ba/0x340
 [<ffffffff81463a65>] xfs_bmap_alloc+0x35/0x40
 [<ffffffff8146f111>] xfs_bmapi_allocate+0xf1/0x350
 [<ffffffff8146f9de>] xfs_bmapi_write+0x66e/0xa60
 [<ffffffff8144538a>] xfs_iomap_write_direct+0x22a/0x3f0
 [<ffffffff8143707b>] __xfs_get_blocks+0x38b/0x5d0
 [<ffffffff814372d4>] xfs_get_blocks_direct+0x14/0x20
 [<ffffffff811b0081>] do_blockdev_direct_IO+0xf71/0x1eb0
 [<ffffffff811b1015>] __blockdev_direct_IO+0x55/0x60
 [<ffffffff814355ca>] xfs_vm_direct_IO+0x11a/0x1e0
 [<ffffffff8112d617>] generic_file_direct_write+0xd7/0x1b0
 [<ffffffff8143e16c>] xfs_file_dio_aio_write+0x13c/0x320
 [<ffffffff8143e6f2>] xfs_file_aio_write+0x1c2/0x1d0
 [<ffffffff81174a07>] do_sync_write+0xa7/0xe0
 [<ffffffff81175288>] vfs_write+0xa8/0x160
 [<ffffffff81175702>] sys_pwrite64+0x92/0xb0
 [<ffffffff81b68f69>] system_call_fastpath+0x16/0x1b

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-08-23 14:48:16 -05:00
Bjorn Helgaas 0ff9514b57 PCI: Don't print anything while decoding is disabled
If we try to print to the console device while its decoding is disabled,
the system will hang.

Reported-and-tested-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Olof Johansson <olof@lixom.net>
2012-08-23 10:53:08 -06:00
Fengguang Wu a0dfb2634e af_packet: match_fanout_group() can be static
cc: Eric Leblond <eric@regit.org>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-23 09:27:12 -07:00
Konrad Rzeszutek Wilk 3287318764 xen/mmu: If the revector fails, don't attempt to revector anything else.
If the P2M revectoring would fail, we would try to continue on by
cleaning the PMD for L1 (PTE) page-tables. The xen_cleanhighmap
is greedy and erases the PMD on both boundaries. Since the P2M
array can share the PMD, we would wipe out part of the __ka
that is still used in the P2M tree to point to P2M leafs.

This fixes it by bypassing the revectoring and continuing on.
If the revector fails, a nice WARN is printed so we can still
troubleshoot this.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:52:17 -04:00
Konrad Rzeszutek Wilk 3fc509fc0c xen/p2m: When revectoring deal with holes in the P2M array.
When we free the PFNs and then subsequently populate them back
during bootup:

Freeing 20000-20200 pfn range: 512 pages freed
1-1 mapping on 20000->20200
Freeing 40000-40200 pfn range: 512 pages freed
1-1 mapping on 40000->40200
Freeing bad80-badf4 pfn range: 116 pages freed
1-1 mapping on bad80->badf4
Freeing badf6-bae7f pfn range: 137 pages freed
1-1 mapping on badf6->bae7f
Freeing bb000-100000 pfn range: 282624 pages freed
1-1 mapping on bb000->100000
Released 283999 pages of unused memory
Set 283999 page(s) to 1-1 mapping
Populating 1acb8a-1f20e9 pfn range: 283999 pages added

We end up having the P2M array (that is the one that was
grafted on the P2M tree) filled with IDENTITY_FRAME or
INVALID_P2M_ENTRY) entries. The patch titled

"xen/p2m: Reuse existing P2M leafs if they are filled with 1:1 PFNs or INVALID."
recycles said slots and replaces the P2M tree leaf's with
 &mfn_list[xx] with p2m_identity or p2m_missing.

And re-uses the P2M array sections for other P2M tree leaf's.
For the above mentioned bootup excerpt, the PFNs at
0x20000->0x20200 are going to be IDENTITY based:

P2M[0][256][0] -> P2M[0][257][0] get turned in IDENTITY_FRAME.

We can re-use that and replace P2M[0][256] to point to p2m_identity.
The "old" page (the grafted P2M array provided by Xen) that was at
P2M[0][256] gets put somewhere else. Specifically at P2M[6][358],
b/c when we populate back:

Populating 1acb8a-1f20e9 pfn range: 283999 pages added

we fill P2M[6][358][0] (and P2M[6][358], P2M[6][359], ...) with
the new MFNs.

That is all OK, except when we revector we assume that the PFN
count would be the same in the grafted P2M array and in the
newly allocated. Since that is no longer the case, as we have
holes in the P2M that point to p2m_missing or p2m_identity we
have to take that into account.

[v2: Check for overflow]
[v3: Move within the __va check]
[v4: Fix the computation]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:52:16 -04:00
Konrad Rzeszutek Wilk 785f623149 xen/mmu: Release just the MFN list, not MFN list and part of pagetables.
We call memblock_reserve for [start of mfn list] -> [PMD aligned end
of mfn list] instead of <start of mfn list> -> <page aligned end of mfn list].

This has the disastrous effect that if at bootup the end of mfn_list is
not PMD aligned we end up returning to memblock parts of the region
past the mfn_list array. And those parts are the PTE tables with
the disastrous effect of seeing this at bootup:

Write protecting the kernel read-only data: 10240k
Freeing unused kernel memory: 1860k freed
Freeing unused kernel memory: 200k freed
(XEN) mm.c:2429:d0 Bad type (saw 1400000000000002 != exp 7000000000000000) for mfn 116a80 (pfn 14e26)
...
(XEN) mm.c:908:d0 Error getting mfn 116a83 (pfn 14e2a) from L1 entry 8000000116a83067 for l1e_owner=0, pg_owner=0
(XEN) mm.c:908:d0 Error getting mfn 4040 (pfn 5555555555555555) from L1 entry 0000000004040601 for l1e_owner=0, pg_owner=0
.. and so on.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:52:16 -04:00
Konrad Rzeszutek Wilk 3aca7fbc8e xen/mmu: Remove from __ka space PMD entries for pagetables.
Please first read the description in "xen/mmu: Copy and revector the
P2M tree."

At this stage, the __ka address space (which is what the old
P2M tree was using) is partially disassembled. The cleanup_highmap
has removed the PMD entries from 0-16MB and anything past _brk_end
up to the max_pfn_mapped (which is the end of the ramdisk).

The xen_remove_p2m_tree and code around has ripped out the __ka for
the old P2M array.

Here we continue on doing it to where the Xen page-tables were.
It is safe to do it, as the page-tables are addressed using __va.
For good measure we delete anything that is within MODULES_VADDR
and up to the end of the PMD.

At this point the __ka only contains PMD entries for the start
of the kernel up to __brk.

[v1: Per Stefano's suggestion wrapped the MODULES_VADDR in debug]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:52:15 -04:00
Konrad Rzeszutek Wilk 7f9140626c xen/mmu: Copy and revector the P2M tree.
Please first read the description in "xen/p2m: Add logic to revector a
P2M tree to use __va leafs" patch.

The 'xen_revector_p2m_tree()' function allocates a new P2M tree
copies the contents of the old one in it, and returns the new one.

At this stage, the __ka address space (which is what the old
P2M tree was using) is partially disassembled. The cleanup_highmap
has removed the PMD entries from 0-16MB and anything past _brk_end
up to the max_pfn_mapped (which is the end of the ramdisk).

We have revectored the P2M tree (and the one for save/restore as well)
to use new shiny __va address to new MFNs. The xen_start_info
has been taken care of already in 'xen_setup_kernel_pagetable()' and
xen_start_info->shared_info in 'xen_setup_shared_info()', so
we are free to roam and delete PMD entries - which is exactly what
we are going to do. We rip out the __ka for the old P2M array.

[v1: Fix smatch warnings]
[v2: memset was doing 0 instead of 0xff]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:52:14 -04:00
Konrad Rzeszutek Wilk 357a3cfb14 xen/p2m: Add logic to revector a P2M tree to use __va leafs.
During bootup Xen supplies us with a P2M array. It sticks
it right after the ramdisk, as can be seen with a 128GB PV guest:

(certain parts removed for clarity):
xc_dom_build_image: called
xc_dom_alloc_segment:   kernel       : 0xffffffff81000000 -> 0xffffffff81e43000  (pfn 0x1000 + 0xe43 pages)
xc_dom_pfn_to_ptr: domU mapping: pfn 0x1000+0xe43 at 0x7f097d8bf000
xc_dom_alloc_segment:   ramdisk      : 0xffffffff81e43000 -> 0xffffffff925c7000  (pfn 0x1e43 + 0x10784 pages)
xc_dom_pfn_to_ptr: domU mapping: pfn 0x1e43+0x10784 at 0x7f0952dd2000
xc_dom_alloc_segment:   phys2mach    : 0xffffffff925c7000 -> 0xffffffffa25c7000  (pfn 0x125c7 + 0x10000 pages)
xc_dom_pfn_to_ptr: domU mapping: pfn 0x125c7+0x10000 at 0x7f0942dd2000
xc_dom_alloc_page   :   start info   : 0xffffffffa25c7000 (pfn 0x225c7)
xc_dom_alloc_page   :   xenstore     : 0xffffffffa25c8000 (pfn 0x225c8)
xc_dom_alloc_page   :   console      : 0xffffffffa25c9000 (pfn 0x225c9)
nr_page_tables: 0x0000ffffffffffff/48: 0xffff000000000000 -> 0xffffffffffffffff, 1 table(s)
nr_page_tables: 0x0000007fffffffff/39: 0xffffff8000000000 -> 0xffffffffffffffff, 1 table(s)
nr_page_tables: 0x000000003fffffff/30: 0xffffffff80000000 -> 0xffffffffbfffffff, 1 table(s)
nr_page_tables: 0x00000000001fffff/21: 0xffffffff80000000 -> 0xffffffffa27fffff, 276 table(s)
xc_dom_alloc_segment:   page tables  : 0xffffffffa25ca000 -> 0xffffffffa26e1000  (pfn 0x225ca + 0x117 pages)
xc_dom_pfn_to_ptr: domU mapping: pfn 0x225ca+0x117 at 0x7f097d7a8000
xc_dom_alloc_page   :   boot stack   : 0xffffffffa26e1000 (pfn 0x226e1)
xc_dom_build_image  : virt_alloc_end : 0xffffffffa26e2000
xc_dom_build_image  : virt_pgtab_end : 0xffffffffa2800000

So the physical memory and virtual (using __START_KERNEL_map addresses)
layout looks as so:

  phys                             __ka
/------------\                   /-------------------\
| 0          | empty             | 0xffffffff80000000|
| ..         |                   | ..                |
| 16MB       | <= kernel starts  | 0xffffffff81000000|
| ..         |                   |                   |
| 30MB       | <= kernel ends => | 0xffffffff81e43000|
| ..         |  & ramdisk starts | ..                |
| 293MB      | <= ramdisk ends=> | 0xffffffff925c7000|
| ..         |  & P2M starts     | ..                |
| ..         |                   | ..                |
| 549MB      | <= P2M ends    => | 0xffffffffa25c7000|
| ..         | start_info        | 0xffffffffa25c7000|
| ..         | xenstore          | 0xffffffffa25c8000|
| ..         | cosole            | 0xffffffffa25c9000|
| 549MB      | <= page tables => | 0xffffffffa25ca000|
| ..         |                   |                   |
| 550MB      | <= PGT end     => | 0xffffffffa26e1000|
| ..         | boot stack        |                   |
\------------/                   \-------------------/

As can be seen, the ramdisk, P2M and pagetables are taking
a bit of __ka addresses space. Which is a problem since the
MODULES_VADDR starts at 0xffffffffa0000000 - and P2M sits
right in there! This results during bootup with the inability to
load modules, with this error:

------------[ cut here ]------------
WARNING: at /home/konrad/ssd/linux/mm/vmalloc.c:106 vmap_page_range_noflush+0x2d9/0x370()
Call Trace:
 [<ffffffff810719fa>] warn_slowpath_common+0x7a/0xb0
 [<ffffffff81030279>] ? __raw_callee_save_xen_pmd_val+0x11/0x1e
 [<ffffffff81071a45>] warn_slowpath_null+0x15/0x20
 [<ffffffff81130b89>] vmap_page_range_noflush+0x2d9/0x370
 [<ffffffff81130c4d>] map_vm_area+0x2d/0x50
 [<ffffffff811326d0>] __vmalloc_node_range+0x160/0x250
 [<ffffffff810c5369>] ? module_alloc_update_bounds+0x19/0x80
 [<ffffffff810c6186>] ? load_module+0x66/0x19c0
 [<ffffffff8105cadc>] module_alloc+0x5c/0x60
 [<ffffffff810c5369>] ? module_alloc_update_bounds+0x19/0x80
 [<ffffffff810c5369>] module_alloc_update_bounds+0x19/0x80
 [<ffffffff810c70c3>] load_module+0xfa3/0x19c0
 [<ffffffff812491f6>] ? security_file_permission+0x86/0x90
 [<ffffffff810c7b3a>] sys_init_module+0x5a/0x220
 [<ffffffff815ce339>] system_call_fastpath+0x16/0x1b
---[ end trace fd8f7704fdea0291 ]---
vmalloc: allocation failure, allocated 16384 of 20480 bytes
modprobe: page allocation failure: order:0, mode:0xd2

Since the __va and __ka are 1:1 up to MODULES_VADDR and
cleanup_highmap rids __ka of the ramdisk mapping, what
we want to do is similar - get rid of the P2M in the __ka
address space. There are two ways of fixing this:

 1) All P2M lookups instead of using the __ka address would
    use the __va address. This means we can safely erase from
    __ka space the PMD pointers that point to the PFNs for
    P2M array and be OK.
 2). Allocate a new array, copy the existing P2M into it,
    revector the P2M tree to use that, and return the old
    P2M to the memory allocate. This has the advantage that
    it sets the stage for using XEN_ELF_NOTE_INIT_P2M
    feature. That feature allows us to set the exact virtual
    address space we want for the P2M - and allows us to
    boot as initial domain on large machines.

So we pick option 2).

This patch only lays the groundwork in the P2M code. The patch
that modifies the MMU is called "xen/mmu: Copy and revector the P2M tree."

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:52:13 -04:00
Konrad Rzeszutek Wilk 488f046df9 xen/mmu: Recycle the Xen provided L4, L3, and L2 pages
As we are not using them. We end up only using the L1 pagetables
and grafting those to our page-tables.

[v1: Per Stefano's suggestion squashed two commits]
[v2: Per Stefano's suggestion simplified loop]
[v3: Fix smatch warnings]
[v4: Add more comments]
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:52:12 -04:00
Konrad Rzeszutek Wilk caaf9ecf16 xen/mmu: For 64-bit do not call xen_map_identity_early
B/c we do not need it. During the startup the Xen provides
us with all the initial memory mapped that we need to function.

The initial memory mapped is up to the bootstack, which means
we can reference using __ka up to 4.f):

(from xen/interface/xen.h):

 4. This the order of bootstrap elements in the initial virtual region:
   a. relocated kernel image
   b. initial ram disk              [mod_start, mod_len]
   c. list of allocated page frames [mfn_list, nr_pages]
   d. start_info_t structure        [register ESI (x86)]
   e. bootstrap page tables         [pt_base, CR3 (x86)]
   f. bootstrap stack               [register ESP (x86)]

(initial ram disk may be ommitted).

[v1: More comments in git commit]
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:52:07 -04:00
Kim Phillips 1267643dc3 powerpc/fsl: fix "Failed to mount /dev: No such device" errors
Yocto (Built by Poky 7.0) 1.2 root filesystems fail to boot,
at least over nfs, with:

Failed to mount /dev: No such device

Configuring DEVTMPFS fixes it.

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2012-08-23 10:46:20 -05:00
Kim Phillips 823f74733d powerpc/fsl: update defconfigs
run make savedefconfig on fsl defconfigs.

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2012-08-23 10:46:15 -05:00
Konrad Rzeszutek Wilk ae895ed783 xen/mmu: use copy_page instead of memcpy.
After all, this is what it is there for.

Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:33:30 -04:00
Konrad Rzeszutek Wilk 4fac153a7a xen/mmu: Provide comments describing the _ka and _va aliasing issue
Which is that the level2_kernel_pgt (__ka virtual addresses)
and level2_ident_pgt (__va virtual address) contain the same
PMD entries. So if you modify a PTE in __ka, it will be reflected
in __va (and vice-versa).

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:33:29 -04:00
Konrad Rzeszutek Wilk 3699aad047 xen/mmu: The xen_setup_kernel_pagetable doesn't need to return anything.
We don't need to return the new PGD - as we do not use it.

Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:33:28 -04:00
Konrad Rzeszutek Wilk 51faaf2b0d Revert "xen/x86: Workaround 64-bit hypervisor and 32-bit initial domain." and "xen/x86: Use memblock_reserve for sensitive areas."
This reverts commit 806c312e50 and
commit 59b294403e.

And also documents setup.c and why we want to do it that way, which
is that we tried to make the the memblock_reserve more selective so
that it would be clear what region is reserved. Sadly we ran
in the problem wherein on a 64-bit hypervisor with a 32-bit
initial domain, the pt_base has the cr3 value which is not
neccessarily where the pagetable starts! As Jan put it: "
Actually, the adjustment turns out to be correct: The page
tables for a 32-on-64 dom0 get allocated in the order "first L1",
"first L2", "first L3", so the offset to the page table base is
indeed 2. When reading xen/include/public/xen.h's comment
very strictly, this is not a violation (since there nothing is said
that the first thing in the page table space is pointed to by
pt_base; I admit that this seems to be implied though, namely
do I think that it is implied that the page table space is the
range [pt_base, pt_base + nt_pt_frames), whereas that
range here indeed is [pt_base - 2, pt_base - 2 + nt_pt_frames),
which - without a priori knowledge - the kernel would have
difficulty to figure out)." - so lets just fall back to the
easy way and reserve the whole region.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 11:33:27 -04:00
Arnd Bergmann 57f0b20141 Merge branch 'randconfig/mach' into fixes
Small platform specific bug fixes for problems found in randconfig builds.

* randconfig/mach:
  ARM: ux500: don't select LEDS_GPIO for snowball
  ARM: imx: build i.MX6 functions only when needed
  ARM: imx: select CPU_FREQ_TABLE when needed
  ARM: imx: fix ksz9021rn_phy_fixup
  ARM: imx: build pm-imx5 code only when PM is enabled
  ARM: omap: allow building omap44xx without SMP

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-08-23 17:30:54 +02:00
Arnd Bergmann db43b18468 ARM: ux500: don't select LEDS_GPIO for snowball
Using 'select' in Kconfig is hard, a platform cannot just
enable a driver without also making sure that its subsystem
is there. Also, there is no actual code dependency between
the platform and the gpio leds driver.

Without this patch, building without LEDS_CLASS esults in:

drivers/built-in.o: In function `create_gpio_led.part.2':
governor_userspace.c:(.devinit.text+0x5a58): undefined reference to `led_classdev_register'
drivers/built-in.o: In function `gpio_led_remove':
governor_userspace.c:(.devexit.text+0x6b8): undefined reference to `led_classdev_unregister'

This reverts 8733f53c6 "ARM: ux500: Kconfig: Compile in leds-gpio
support for Snowball" that introduced the regression and did not
provide a helpful explanation.

In order to leave the GPIO LED code still present in normal
builds, this also enables the symbol in u8500_defconfig, in addition
to the other LED drivers that are already selected there.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Lee Jones <lee.jones@linaro.org>
2012-08-23 17:27:45 +02:00
Arnd Bergmann 1fc593feaf ARM: imx: build i.MX6 functions only when needed
The head-v7.S contains a call to the generic cpu_suspend function,
which is only available when selected by the i.MX6 code. As
pointed out by Shawn Guo, i.MX5 does not actually use any
functions defined in head-v7.S. It is also needed only for
the i.MX6 power management code and for the SMP code, so
we can restrict building this file to situations in which
at least one of those two is present.

Finally, other platforms with a similar file call it headsmp.S,
so we can rename it to the same for consistency.

Without this patch, building imx5 standalone results in:

arch/arm/mach-imx/built-in.o: In function `v7_cpu_resume':
arch/arm/mach-imx/head-v7.S:104: undefined reference to `cpu_resume'

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Eric Miao <eric.miao@linaro.org>
Cc: stable@vger.kernel.org
2012-08-23 17:26:53 +02:00
Arnd Bergmann f637c4c940 ARM: imx: select CPU_FREQ_TABLE when needed
The i.MX cpufreq implementation uses the CPU_FREQ_TABLE helpers,
so it needs to select that code to be built. This problem has
apparently existed since the i.MX cpufreq code was first merged
in v2.6.37.

Building IMX without CPU_FREQ_TABLE results in:

arch/arm/plat-mxc/built-in.o: In function `mxc_cpufreq_exit':
arch/arm/plat-mxc/cpufreq.c:173: undefined reference to `cpufreq_frequency_table_put_attr'
arch/arm/plat-mxc/built-in.o: In function `mxc_set_target':
arch/arm/plat-mxc/cpufreq.c:84: undefined reference to `cpufreq_frequency_table_target'
arch/arm/plat-mxc/built-in.o: In function `mxc_verify_speed':
arch/arm/plat-mxc/cpufreq.c:65: undefined reference to `cpufreq_frequency_table_verify'
arch/arm/plat-mxc/built-in.o: In function `mxc_cpufreq_init':
arch/arm/plat-mxc/cpufreq.c:154: undefined reference to `cpufreq_frequency_table_cpuinfo'
arch/arm/plat-mxc/cpufreq.c:162: undefined reference to `cpufreq_frequency_table_get_attr'

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Yong Shen <yong.shen@linaro.org>
Cc: stable@vger.kernel.org
2012-08-23 17:16:43 +02:00
Arnd Bergmann 9f9ba0fdec ARM: imx: fix ksz9021rn_phy_fixup
The ksz9021rn_phy_fixup and mx6q_sabrelite functions try to
set up an ethernet phy if they can. They do check whether
phylib is enabled, but unfortunately the functions can only
be called from platform code if phylib is builtin, not
if it is a module

Without this patch, building with a modular phylib results in:

arch/arm/mach-imx/mach-imx6q.c: In function 'imx6q_sabrelite_init':
arch/arm/mach-imx/mach-imx6q.c:120:5: error: 'ksz9021rn_phy_fixup' undeclared (first use in this function)
arch/arm/mach-imx/mach-imx6q.c:120:5: note: each undeclared identifier is reported only once for each function it appears in

The bug was originally reported by Artem Bityutskiy but only
partially fixed in ef441806 "ARM: imx6q: register phy fixup only when
CONFIG_PHYLIB is enabled".

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
2012-08-23 17:16:43 +02:00
Arnd Bergmann a28eecef8a ARM: imx: build pm-imx5 code only when PM is enabled
This moves the imx5 pm code out of the list of unconditionally
compiled files for imx5, mirroring what we already do for imx6
and how it was done before the code was move from mach-mx5 to
mach-imx in v3.3.

Without this patch, building with CONFIG_PM disabled results in:

arch/arm/mach-imx/pm-imx5.c:202:116: error: redefinition of 'imx51_pm_init'
arch/arm/mach-imx/include/mach-imx/common.h:154:91: note: previous definition of 'imx51_pm_init' was here
arch/arm/mach-imx/pm-imx5.c:209:116: error: redefinition of 'imx53_pm_init'
arch/arm/mach-imx/include/mach-imx/common.h:155:91: note: previous definition of 'imx53_pm_init' was here

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: stable@vger.kernel.org
2012-08-23 17:16:42 +02:00
Arnd Bergmann c7a9b09b1a ARM: omap: allow building omap44xx without SMP
The new omap4 cpuidle implementation currently requires
ARCH_NEEDS_CPU_IDLE_COUPLED, which only works on SMP.

This patch makes it possible to build a non-SMP kernel
for that platform. This is not normally desired for
end-users but can be useful for testing.

Without this patch, building rand-0y2jSKT results in:

drivers/cpuidle/coupled.c: In function 'cpuidle_coupled_poke':
drivers/cpuidle/coupled.c:317:3: error: implicit declaration of function '__smp_call_function_single' [-Werror=implicit-function-declaration]

It's not clear if this patch is the best solution for
the problem at hand. I have made sure that we can now
build the kernel in all configurations, but that does
not mean it will actually work on an OMAP44xx.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
2012-08-23 17:16:42 +02:00
Arnd Bergmann 5f870baa18 Here are two audio fixes for the ux500 found by Lee Jones.
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Merge tag 'ux500-fixes-v3.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-stericsson into fixes

From Linus Walleij <linus.walleij@linaro.org>:
Here are two audio fixes for the ux500 found by Lee Jones.

* tag 'ux500-fixes-v3.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-stericsson:
  ARM: ux500: Ensure probing of Audio devices when Device Tree is enabled
  ARM: ux500: Fix merge error, no matching driver name for 'snd_soc_u8500'

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-08-23 17:06:15 +02:00
Arnd Bergmann 8917da43cc Merge branch 'v3.6-samsung-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into fixes
From Kukjin Kim <kgene.kim@samsung.com>:

For HDMI, already HDMI support for EXYNOS in mainline kernel is broken
because its configuration moved to platform data but regarding platform
data didn't support yet. And others are for fix warnings.

* 'v3.6-samsung-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
  ARM: EXYNOS: Set HDMI platform data in Origen board
  ARM: EXYNOS: Set HDMI platform data in SMDKV310
  ARM: SAMSUNG: Add API to set platform data for s5p-tv driver
  ARM: SAMSUNG: Set HDMI platform data for Exynos4x12 SoCs
  ARM: Samsung: Make uart_save static in pm.c file
  ARM: S3C24XX: Fix s3c2410_dma_enqueue parameters
  ARM: S3C24XX: Add missing DMACH_DT_PROP

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-08-23 17:03:49 +02:00
Arnd Bergmann 1e72fe1fca Merge branch 'imx/fixes-for-3.6' of git://git.linaro.org/people/shawnguo/linux-2.6 into fixes
* 'imx/fixes-for-3.6' of git://git.linaro.org/people/shawnguo/linux-2.6:
  ARM: dts: imx51-babbage: fix esdhc cd/wp properties
  ARM: imx6: spin the cpu until hardware takes it down
  ARM i.MX6q: Add virtual 1/3.5 dividers in the LDB clock path

Also updates to Linux 3.6-rc2

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-08-23 17:02:42 +02:00
Konrad Rzeszutek Wilk 6d7083eee3 xen/swiotlb: Fix compile warnings when using plain integer instead of NULL pointer.
arch/x86/xen/pci-swiotlb-xen.c:96:1: warning: Using plain integer as NULL pointer
arch/x86/xen/pci-swiotlb-xen.c:96:1: warning: Using plain integer as NULL pointer

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 10:19:03 -04:00
Konrad Rzeszutek Wilk a8752fd9a4 xen/swiotlb: Remove functions not needed anymore.
Sparse warns us off:
drivers/xen/swiotlb-xen.c:506:1: warning: symbol 'xen_swiotlb_map_sg' was not declared. Should it be static?
drivers/xen/swiotlb-xen.c:534:1: warning: symbol 'xen_swiotlb_unmap_sg' was not declared. Should it be static?

and it looks like we do not need this function at all.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 10:18:56 -04:00
Stefano Stabellini 1a1d43318a xen: allow privcmd for HVM guests
This patch removes the "return -ENOSYS" for auto_translated_physmap
guests from privcmd_mmap, thus it allows ARM guests to issue privcmd
mmap calls. However privcmd mmap calls are still going to fail for HVM
and hybrid guests on x86 because the xen_remap_domain_mfn_range
implementation is currently PV only.

Changes in v2:

- better commit message;
- return -EINVAL from xen_remap_domain_mfn_range if
  auto_translated_physmap.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 10:18:20 -04:00
Stefano Stabellini bd3f79b71d xen: Introduce xen_pfn_t for pfn and mfn types
All the original Xen headers have xen_pfn_t as mfn and pfn type, however
when they have been imported in Linux, xen_pfn_t has been replaced with
unsigned long. That might work for x86 and ia64 but it does not for arm.
Bring back xen_pfn_t and let each architecture define xen_pfn_t as they
see fit.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 10:18:17 -04:00
Stefano Stabellini a8636c0b2e xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST
Reset the IRQ_NOAUTOEN and IRQ_NOREQUEST flags that are enabled by
default on ARM. If IRQ_NOAUTOEN is set, __setup_irq doesn't call
irq_startup, that is responsible for calling irq_unmask at startup time.
As a result event channels remain masked.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 10:18:12 -04:00
Stefano Stabellini b5e579232d xen/events: fix unmask_evtchn for PV on HVM guests
When unmask_evtchn is called, if we already have an event pending, we
just set evtchn_pending_sel waiting for local_irq_enable to be called.
That is because PV guests set the irq_enable pvops to
xen_irq_enable_direct in xen_setup_vcpu_info_placement:
xen_irq_enable_direct is implemented in assembly in
arch/x86/xen/xen-asm.S and call xen_force_evtchn_callback if
XEN_vcpu_info_pending is set.

However HVM guests (and ARM guests) do not change or do not have the
irq_enable pvop, so evtchn_unmask cannot work properly for them.

Considering that having the pending_irq bit set when unmask_evtchn is
called is not very common, and it is simpler to keep the
native_irq_enable implementation for HVM guests (and ARM guests), the
best thing to do is just use the EVTCHNOP_unmask hypercall (Xen
re-injects pending events in response).

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 10:18:07 -04:00
Daniel De Graaf 5c13f80677 xen/sysfs: Use XENVER_guest_handle to query UUID
This hypercall has been present since Xen 3.1, and is the preferred
method for a domain to obtain its UUID. Fall back to the xenstore method
if using an older version of Xen (which returns -ENOSYS).

Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 10:16:18 -04:00
Konrad Rzeszutek Wilk c96aae1f7f xen/setup: Fix one-off error when adding for-balloon PFNs to the P2M.
When we are finished with return PFNs to the hypervisor, then
populate it back, and also mark the E820 MMIO and E820 gaps
as IDENTITY_FRAMEs, we then call P2M to set areas that can
be used for ballooning. We were off by one, and ended up
over-writting a P2M entry that most likely was an IDENTITY_FRAME.
For example:

1-1 mapping on 40000->40200
1-1 mapping on bc558->bc5ac
1-1 mapping on bc5b4->bc8c5
1-1 mapping on bc8c6->bcb7c
1-1 mapping on bcd00->100000
Released 614 pages of unused memory
Set 277889 page(s) to 1-1 mapping
Populating 40200-40466 pfn range: 614 pages added

=> here we set from 40466 up to bc559 P2M tree to be
INVALID_P2M_ENTRY. We should have done it up to bc558.

The end result is that if anybody is trying to construct
a PTE for PFN bc558 they end up with ~PAGE_PRESENT.

CC: stable@vger.kernel.org
Reported-by-and-Tested-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23 10:14:52 -04:00
John W. Linville c6b6eedc29 Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211 2012-08-23 09:51:15 -04:00
Gabor Juhos a1dca315ce MIPS: pci-ar724x: avoid data bus error due to a missing PCIe module
If the controller has no PCIe module attached, accessing of the device
configuration space causes a data bus error. Avoid this by checking the
status of the PCIe link in advance, and indicate an error if the link
is down.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: stable@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/4293/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-08-23 15:44:47 +02:00
Shawn Guo a46d2619d7 ARM: dts: imx51-babbage: fix esdhc cd/wp properties
The binding doc and dts use properties "fsl,{cd,wp}-internal" while
esdhc driver uses "fsl,{cd,wp}-controller".  Fix binding doc and dts
to get them match driver code.

Reported-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: <stable@vger.kernel.org>
Acked-by: Chris Ball <cjb@laptop.org>
2012-08-23 21:10:23 +08:00
Shawn Guo c944b0b935 ARM: imx6: spin the cpu until hardware takes it down
Though commit 602bf40 (ARM: imx6: exit coherency when shutting down
a cpu) improves the stability of imx6q cpu hotplug a lot, there are
still hangs seen with a more stressful hotplug testing.

It's expected that once imx_enable_cpu(cpu, false) is called, the cpu
will be taken down by hardware immediately, and the code after that
will not get any chance to execute.  However, this is not always the
case from the testing.  The cpu could possibly be alive for a few
cycles before hardware actually takes it down.  So rather than letting
cpu execute some code that could cause a hang in these cycles, let's
make the cpu spin there and wait for hardware to take it down.

Cc: <stable@vger.kernel.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
2012-08-23 21:10:22 +08:00