... instead of naked numbers.

Stuff in sysrq.c used to set it to 8 which is supposed to mean above
default level so set it to DEBUG instead as we're terminating/killing all
tasks and we want to be verbose there.

Also, correct the check in x86_64_start_kernel which should be >= as
we're clearly issuing the string there for all debug levels, not only
the magical 10.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NKees Cook <keescook@chromium.org>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Cc: Joe Perches <joe@perches.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

sys_sgetmask and sys_ssetmask are obsolete system calls no longer
supported in libc.

This patch replaces architecture related __ARCH_WANT_SYS_SGETMAX by expert
mode configuration.That option is enabled by default for those
architectures.
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove an unused global variable mce_entry and relative operations in
do_machine_check().
Signed-off-by: NChen Yucong <slaoub@gmail.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NEmil Medve <Emilian.Medve@Freescale.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Tracking dirty status on 2 level pages requires very ugly macros and
taking into account how old the machines who can operate without PAE
mode only are, lets drop soft dirty tracker from them for code
simplicity (note I can't drop all the macros from 2 level pages by now
since _PAGE_BIT_PROTNONE and _PAGE_BIT_FILE are still used even without
tracker).

Linus proposed to completely rip off softdirty support on x86-32 (even
with PAE) and since for CRIU we're not planning to support native x86-32
mode, lets do that.

(Softdirty tracker is relatively new feature which is mostly used by
CRIU so I don't expect if such API change would cause problems for
userspace).
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Noonan <steven@uplinklabs.net>
Cc: Rik van Riel <riel@redhat.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

_PAGE_BIT_FILE (bit 6) is always less than _PAGE_BIT_PROTNONE (bit 8), so
drop redundant #ifdef.
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Noonan <steven@uplinklabs.net>
Cc: Rik van Riel <riel@redhat.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

dma_generic_alloc_coherent() firstly attempts to allocate by
dma_alloc_from_contiguous() if CONFIG_DMA_CMA is enabled.  But the
memory region allocated by it may not fit within the device's DMA mask.
This change makes it fall back to usual alloc_pages_node() allocation
for such cases.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, "cma=" kernel parameter is used to specify the size of CMA,
but we can't specify where it is located.  We want to locate CMA below
4GB for devices only supporting 32-bit addressing on 64-bit systems
without iommu.

This enables to specify the placement of CMA by extending "cma=" kernel
parameter.

Examples:
 1. locate 64MB CMA below 4GB by "cma=64M@0-4G"
 2. locate 64MB CMA exact at 512MB by "cma=64M@512M"

Note that the DMA contiguous memory allocator on x86 assumes that
page_address() works for the pages to allocate.  So this change requires
to limit end address of contiguous memory area upto max_pfn_mapped to
prevent from locating it on highmem area by the argument of
dma_contiguous_reserve().
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The DMA Contiguous Memory Allocator support on x86 is disabled when
swiotlb config option is enabled.  So DMA CMA is always disabled on
x86_64 because swiotlb is always enabled.  This attempts to support for
DMA CMA with enabling swiotlb config option.

The contiguous memory allocator on x86 is integrated in the function
dma_generic_alloc_coherent() which is .alloc callback in nommu_dma_ops
for dma_alloc_coherent().

x86_swiotlb_alloc_coherent() which is .alloc callback in swiotlb_dma_ops
tries to allocate with dma_generic_alloc_coherent() firstly and then
swiotlb_alloc_coherent() is called as a fallback.

The main part of supporting DMA CMA with swiotlb is that changing
x86_swiotlb_free_coherent() which is .free callback in swiotlb_dma_ops
for dma_free_coherent() so that it can distinguish memory allocated by
dma_generic_alloc_coherent() from one allocated by
swiotlb_alloc_coherent() and release it with dma_generic_free_coherent()
which can handle contiguous memory.  This change requires making
is_swiotlb_buffer() global function.

This also needs to change .free callback in the dma_map_ops for amd_gart
and sta2x11, because these dma_ops are also using
dma_generic_alloc_coherent().
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Acked-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patchset enhances the DMA Contiguous Memory Allocator on x86.

Currently the DMA CMA is only supported with pci-nommu dma_map_ops and
furthermore it can't be enabled on x86_64.  But I would like to allocate
big contiguous memory with dma_alloc_coherent() and tell it to the device
that requires it, regardless of which dma mapping implementation is
actually used in the system.

So this makes it work with swiotlb and intel-iommu dma_map_ops, too.  And
this also extends "cma=" kernel parameter to specify placement constraint
by the physical address range of memory allocations.  For example, CMA
allocates memory below 4GB by "cma=64M@0-4G", it is required for the
devices only supporting 32-bit addressing on 64-bit systems without iommu.

This patch (of 5):

Calling dma_alloc_coherent() with __GFP_ZERO must return zeroed memory.

But when the contiguous memory allocator (CMA) is enabled on x86 and the
memory region is allocated by dma_alloc_from_contiguous(), it doesn't
return zeroed memory.  Because dma_generic_alloc_coherent() forgot to fill
the memory region with zero if it was allocated by
dma_alloc_from_contiguous()

Most implementations of dma_alloc_coherent() return zeroed memory
regardless of whether __GFP_ZERO is specified.  So this fixes it by
unconditionally zeroing the allocated memory region.

Alternatively, we could fix dma_alloc_from_contiguous() to return zeroed
out memory and remove memset() from all caller of it.  But we can't simply
remove the memset on arm because __dma_clear_buffer() is used there for
ensuring cache flushing and it is used in many places.  Of course we can
do redundant memset in dma_alloc_from_contiguous(), but I think this patch
is less impact for fixing this problem.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On system with 2TiB ram, current x86_64 have 128M as section size, and
one memory_block only include one section.  So will have 16400 entries
under /sys/devices/system/memory/.

Current code try to use block id to find block pointer in /sys for any
section, and reuse that block pointer.  that finding will take some time
even after commit 7c243c71 ("mm: speedup in __early_pfn_to_nid")
that will skip the search in that case during booting up.

So solution could be increase block size just like SGI UV system did.
(harded code to 2g).

This patch is trying to probe the block size to make it match mmio remap
size.  for example, Intel Nehalem later system will have memory range [0,
TOML), [4g, TOMH].  If the memory hole is 2g and total is 128g, TOM will
be 2g, and TOM2 will be 130g.

We could use 2g as block size instead of default 128M.  That will reduce
number of entries in /sys/devices/system/memory/

On system 6TiB system will reduce boot time by 35 seconds.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

_PAGE_NUMA is currently an alias of _PROT_PROTNONE to trap NUMA hinting
faults on x86.  Care is taken such that _PAGE_NUMA is used only in
situations where the VMA flags distinguish between NUMA hinting faults
and prot_none faults.  This decision was x86-specific and conceptually
it is difficult requiring special casing to distinguish between PROTNONE
and NUMA ptes based on context.

Fundamentally, we only need the _PAGE_NUMA bit to tell the difference
between an entry that is really unmapped and a page that is protected
for NUMA hinting faults as if the PTE is not present then a fault will
be trapped.

Swap PTEs on x86-64 use the bits after _PAGE_GLOBAL for the offset.
This patch shrinks the maximum possible swap size and uses the bit to
uniquely distinguish between NUMA hinting ptes and swap ptes.
Signed-off-by: NMel Gorman <mgorman@suse.de>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Noonan <steven@uplinklabs.net>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

32-bit support for NUMA is an oddity on its own but with automatic NUMA
balancing on top there is a reasonable risk that the CPUPID information
cannot be stored in the page flags.  This patch removes support for
automatic NUMA support on 32-bit x86.
Signed-off-by: NMel Gorman <mgorman@suse.de>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Noonan <steven@uplinklabs.net>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently hugepage migration is available for all archs which support
pmd-level hugepage, but testing is done only for x86_64 and there're
bugs for other archs.  So to avoid breaking such archs, this patch
limits the availability strictly to x86_64 until developers of other
archs get interested in enabling this feature.

Simply disabling hugepage migration on non-x86_64 archs is not enough to
fix the reported problem where sys_move_pages() hits the BUG_ON() in
follow_page(FOLL_GET), so let's fix this by checking if hugepage
migration is supported in vma_migratable().
Signed-off-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reported-by: NMichael Ellerman <mpe@ellerman.id.au>
Tested-by: NMichael Ellerman <mpe@ellerman.id.au>
Acked-by: NHugh Dickins <hughd@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: <stable@vger.kernel.org>	[3.12+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make it a little clearer what the littleendian access macros in
vdso2c.[ch] actually do.  This way they can probably also be moved to
a central location (e.g. tools/include) for the benefit of other host
tools.

We should avoid implementation namespace symbols when writing code
that is compiling for the compiler host, so avoid names starting with
double underscore or underscore-capital.
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/2cf258df123cb24bad63c274c8563c050547d99d.1401464755.git.luto@amacapital.net

This adds a macro GET(x) to convert x from big-endian to
little-endian.  Hopefully I put it everywhere it needs to go and got
all the cases needed for everyone's linux/elf.h.
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/2cf258df123cb24bad63c274c8563c050547d99d.1401464755.git.luto@amacapital.netSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

This avoids bizarre failures if make is run again.
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/1764385fe9931e8940b9d001132515448ea89523.1401464755.git.luto@amacapital.netSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

There is very little and maybe practically nothing we can do to recover
from a system where at least one core has reached a timeout during the
whole monarch cores gathering. So panic when that happens.

Link: http://lkml.kernel.org/r/20140523091041.GA21332@pd.tnicSigned-off-by: NBorislav Petkov <bp@suse.de>

Check return code of every function called by mcheck_init_device().
Signed-off-by: NMathieu Souchaud <mattieu.souchaud@free.fr>
Link: http://lkml.kernel.org/r/1399151031-19905-1-git-send-email-mattieu.souchaud@free.frSigned-off-by: NBorislav Petkov <bp@suse.de>

While I play inhouse patches with much memory pressure on qemu-kvm,
3.14 kernel was randomly crashed. The reason was kernel stack overflow.

When I investigated the problem, the callstack was a little bit deeper
by involve with reclaim functions but not direct reclaim path.

I tried to diet stack size of some functions related with alloc/reclaim
so did a hundred of byte but overflow was't disappeard so that I encounter
overflow by another deeper callstack on reclaim/allocator path.

Of course, we might sweep every sites we have found for reducing
stack usage but I'm not sure how long it saves the world(surely,
lots of developer start to add nice features which will use stack
agains) and if we consider another more complex feature in I/O layer
and/or reclaim path, it might be better to increase stack size(
meanwhile, stack usage on 64bit machine was doubled compared to 32bit
while it have sticked to 8K. Hmm, it's not a fair to me and arm64
already expaned to 16K. )

So, my stupid idea is just let's expand stack size and keep an eye
toward stack consumption on each kernel functions via stacktrace of ftrace.
For example, we can have a bar like that each funcion shouldn't exceed 200K
and emit the warning when some function consumes more in runtime.
Of course, it could make false positive but at least, it could make a
chance to think over it.

I guess this topic was discussed several time so there might be
strong reason not to increase kernel stack size on x86_64, for me not
knowing so Ccing x86_64 maintainers, other MM guys and virtio
maintainers.

Here's an example call trace using up the kernel stack:

         Depth    Size   Location    (51 entries)
         -----    ----   --------
   0)     7696      16   lookup_address
   1)     7680      16   _lookup_address_cpa.isra.3
   2)     7664      24   __change_page_attr_set_clr
   3)     7640     392   kernel_map_pages
   4)     7248     256   get_page_from_freelist
   5)     6992     352   __alloc_pages_nodemask
   6)     6640       8   alloc_pages_current
   7)     6632     168   new_slab
   8)     6464       8   __slab_alloc
   9)     6456      80   __kmalloc
  10)     6376     376   vring_add_indirect
  11)     6000     144   virtqueue_add_sgs
  12)     5856     288   __virtblk_add_req
  13)     5568      96   virtio_queue_rq
  14)     5472     128   __blk_mq_run_hw_queue
  15)     5344      16   blk_mq_run_hw_queue
  16)     5328      96   blk_mq_insert_requests
  17)     5232     112   blk_mq_flush_plug_list
  18)     5120     112   blk_flush_plug_list
  19)     5008      64   io_schedule_timeout
  20)     4944     128   mempool_alloc
  21)     4816      96   bio_alloc_bioset
  22)     4720      48   get_swap_bio
  23)     4672     160   __swap_writepage
  24)     4512      32   swap_writepage
  25)     4480     320   shrink_page_list
  26)     4160     208   shrink_inactive_list
  27)     3952     304   shrink_lruvec
  28)     3648      80   shrink_zone
  29)     3568     128   do_try_to_free_pages
  30)     3440     208   try_to_free_pages
  31)     3232     352   __alloc_pages_nodemask
  32)     2880       8   alloc_pages_current
  33)     2872     200   __page_cache_alloc
  34)     2672      80   find_or_create_page
  35)     2592      80   ext4_mb_load_buddy
  36)     2512     176   ext4_mb_regular_allocator
  37)     2336     128   ext4_mb_new_blocks
  38)     2208     256   ext4_ext_map_blocks
  39)     1952     160   ext4_map_blocks
  40)     1792     384   ext4_writepages
  41)     1408      16   do_writepages
  42)     1392      96   __writeback_single_inode
  43)     1296     176   writeback_sb_inodes
  44)     1120      80   __writeback_inodes_wb
  45)     1040     160   wb_writeback
  46)      880     208   bdi_writeback_workfn
  47)      672     144   process_one_work
  48)      528     112   worker_thread
  49)      416     240   kthread
  50)      176     176   ret_from_fork

[ Note: the problem is exacerbated by certain gcc versions that seem to
  generate much bigger stack frames due to apparently bad coalescing of
  temporaries and generating too many spills.  Rusty saw gcc-4.6.4 using
  35% more stack on the virtio path than 4.8.2 does, for example.

  Minchan not only uses such a bad gcc version (4.6.3 in his case), but
  some of the stack use is due to debugging (CONFIG_DEBUG_PAGEALLOC is
  what causes that kernel_map_pages() frame, for example). But we're
  clearly getting too close.

  The VM code also seems to have excessive stack frames partly for the
  same compiler reason, triggered by excessive inlining and lots of
  function arguments.

  We need to improve on our stack use, but in the meantime let's do this
  simple stack increase too.  Unlike most earlier reports, there is
  nothing simple that stands out as being really horribly wrong here,
  apart from the fact that the stack frames are just bigger than they
  should need to be.        - Linus ]
Signed-off-by: NMinchan Kim <minchan@kernel.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michael S Tsirkin <mst@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: PJ Waskiewicz <pjwaskiewicz@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Now that CONFIG_USB_DEBUG is gone, remove it from a number of defconfig
files that were enabling it.
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

pcibios_penalize_isa_irq() is only implemented by x86 now, and legacy ISA
is not used by some architectures.  Make pcibios_penalize_isa_irq() a
__weak function to simplify the code.  This removes the need for new
platforms to add stub implementations of pcibios_penalize_isa_irq().

[bhelgaas: changelog, comments]
Signed-off-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

Use pci_is_bridge() to simplify code.  No functional change.

Requires: 326c1cda PCI: Rename pci_is_bridge() to pci_has_subordinate()
Requires: 1c86438c PCI: Add new pci_is_bridge() interface
Signed-off-by: NYijing Wang <wangyijing@huawei.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

early_root_info_init() is now deprecated in favor of info in ACPI.  Add a
note to that effect.  Also, clean up the code a bit.

There is no functional change.
Signed-off-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Since mis-order issues have been solved, we can cleanup redundant
definitions that already have defaults in <acpi/platform/acenv.h>.

This patch removes redudant environments for __KERNEL__ surrounded code.
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There is a mis-order inclusion for <asm/acpi.h>.

As we will enforce including <linux/acpi.h> for all Linux ACPI users, we
can find the inclusion order is as follows:

<linux/acpi.h>
  <acpi/acpi.h>
   <acpi/platform/acenv.h>
    (acenv.h before including aclinux.h)
    <acpi/platform/aclinux.h>
...........................................................................
     (aclinux.h before including asm/acpi.h)
     <asm/acpi.h>                             @Redundant@
      (ACPICA specific stuff)
...........................................................................
...........................................................................
      (Linux ACPI specific stuff) ? - - - - - - - - - - - - +
     (aclinux.h after including asm/acpi.h)   @Invisible@   |
    (acenv.h after including aclinux.h)       @Invisible@   |
   other ACPICA headers                       @Invisible@   |
............................................................|..............
  <acpi/acpi_bus.h>                                         |
  <acpi/acpi_drivers.h>                                     |
  <asm/acpi.h> (Excluded)                                   |
   (Linux ACPI specific stuff) ! <- - - - - - - - - - - - - +

NOTE that, in ACPICA, <acpi/platform/acenv.h> is more like Kconfig
generated <generated/autoconf.h> for Linux, it is meant to be included
before including any ACPICA code.

In the above figure, there is a question mark for "Linux ACPI specific
stuff" in <asm/acpi.h> which should be included after including all other
ACPICA header files.  Thus they really need to be moved to the position
marked with exclaimation mark or the definitions in the blocks marked with
"@Invisible@" will be invisible to such architecture specific "Linux ACPI
specific stuff" header blocks.  This leaves 2 issues:
1. All environmental definitions in these blocks should have a copy in the
   area marked with "@Redundant@" if they are required by the "Linux ACPI
   specific stuff".
2. We cannot use any ACPICA defined types in <asm/acpi.h>.

This patch splits architecture specific ACPICA stuff from <asm/acpi.h> to
fix this issue.
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

When running as a dom0 in PVH mode, foreign pfns that are accessed
must be added to our p2m which is managed by xen. This is done via
XENMEM_add_to_physmap_range hypercall. This is needed for toolstack
building guests and mapping guest memory, xentrace mapping xen pages,
etc.
Signed-off-by: NMukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

MOV CR/DR instructions ignore the mod field (in the ModR/M byte). As the SDM
states: "The 2 bits in the mod field are ignored".  Accordingly, the second
operand of these instructions is always a general purpose register.

The current emulator implementation does not do so. If the mod bits do not
equal 3, it expects the second operand to be in memory.
Signed-off-by: NNadav Amit <namit@cs.technion.ac.il>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When Hyper-V enlightenments are in effect, Windows prefers to issue an
Hyper-V MSR write to issue an EOI rather than an x2apic MSR write.
The Hyper-V MSR write is not handled by the processor, and besides
being slower, this also causes bugs with APIC virtualization.  The
reason is that on EOI the processor will modify the highest in-service
interrupt (SVI) field of the VMCS, as explained in section 29.1.4 of
the SDM; every other step in EOI virtualization is already done by
apic_send_eoi or on VM entry, but this one is missing.

We need to do the same, and be careful not to muck with the isr_count
and highest_isr_cache fields that are unused when virtual interrupt
delivery is enabled.

Cc: stable@vger.kernel.org
Reviewed-by: NYang Zhang <yang.z.zhang@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Print the AGP bridge info the same way as the rest of the kernel, e.g.,
"0000:00:04.0" instead of "00:04:00".

Also print the AGP aperture address range the same way we print resources,
and label it explicitly as a bus address range.

No functional change except the message changes.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Replace printk() with pr_info(), pr_err(), etc.  Define pr_fmt() to prefix
output with "AGP: ".

No functional change except the addition of "AGP: " prefix in dmesg output.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Move the pcibios_assign_resources() fs_initcall annotation next to the
function definition.  No functional change.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

The DR7 masking which is done on task switch emulation should be in hex format
(clearing the local breakpoints enable bits 0,2,4 and 6).
Signed-off-by: NNadav Amit <namit@cs.technion.ac.il>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

I noticed on some of my systems that page fault tracing doesn't
work:

	cd /sys/kernel/debug/tracing
	echo 1 > events/exceptions/enable
	cat trace;
	# nothing shows up

I eventually traced it down to CONFIG_KVM_GUEST.  At least in a
KVM VM, enabling that option breaks page fault tracing, and
disabling fixes it.  I tried on some old kernels and this does
not appear to be a regression: it never worked.

There are two page-fault entry functions today.  One when tracing
is on and another when it is off.  The KVM code calls do_page_fault()
directly instead of calling the traced version:

> dotraplinkage void __kprobes
> do_async_page_fault(struct pt_regs *regs, unsigned long
> error_code)
> {
>         enum ctx_state prev_state;
>
>         switch (kvm_read_and_reset_pf_reason()) {
>         default:
>                 do_page_fault(regs, error_code);
>                 break;
>         case KVM_PV_REASON_PAGE_NOT_PRESENT:

I'm also having problems with the page fault tracing on bare
metal (same symptom of no trace output).  I'm unsure if it's
related.

Steven had an alternative to this which has zero overhead when
tracing is off where this includes the standard noops even when
tracing is disabled.  I'm unconvinced that the extra complexity
of his apporach:

	http://lkml.kernel.org/r/20140508194508.561ed220@gandalf.local.home

is worth it, expecially considering that the KVM code is already
making page fault entry slower here.  This solution is
dirt-simple.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: kvm@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Acked-by: N"H. Peter Anvin" <hpa@zytor.com>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

CS.RPL is not equal to the CPL in the few instructions between
setting CR0.PE and reloading CS.  And CS.DPL is also not equal
to the CPL for conforming code segments.

However, SS.DPL *is* always equal to the CPL except for the weird
case of SYSRET on AMD processors, which sets SS.DPL=SS.RPL from the
value in the STAR MSR, but force CPL=3 (Intel instead forces
SS.DPL=SS.RPL=CPL=3).

So this patch:

- modifies SVM to update the CPL from SS.DPL rather than CS.RPL;
the above case with SYSRET is not broken further, and the way
to fix it would be to pass the CPL to userspace and back

- modifies VMX to always return the CPL from SS.DPL (except
forcing it to 0 if we are emulating real mode via vm86 mode;
in vm86 mode all DPLs have to be 3, but real mode does allow
privileged instructions).  It also removes the CPL cache,
which becomes a duplicate of the SS access rights cache.

This fixes doing KVM_IOCTL_SET_SREGS exactly after setting
CR0.PE=1 but before CS has been reloaded.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Table 7-1 of the SDM mentions a check that the code segment's
DPL must match the selector's RPL.  This was not done by KVM,
fix it.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Not needed anymore now that the CPL is computed directly
during task switch.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

During task switch, all of CS.DPL, CS.RPL, SS.DPL must match (in addition
to all the other requirements) and will be the new CPL.  So far this
worked by carefully setting the CS selector and flag before doing the
task switch; setting CS.selector will already change the CPL.

However, this will not work once we get the CPL from SS.DPL, because
then you will have to set the full segment descriptor cache to change
the CPL.  ctxt->ops->cpl(ctxt) will then return the old CPL during the
task switch, and the check that SS.DPL == CPL will fail.

Temporarily assume that the CPL comes from CS.RPL during task switch
to a protected-mode task.  This is the same approach used in QEMU's
emulation code, which (until version 2.0) manually tracks the CPL.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

One more specialized entry function is now gone.  Again, this seems
to only change line numbers in entry_64.o.
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/f54854f07ff3be8162b166124dbead23feeefe10.1400709717.git.luto@amacapital.netSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

I haven't touched the device interrupt code, which is different
enough that it's probably not worth merging, and I haven't done
anything about paranoidzeroentry_ist yet.

This appears to produce an entry_64.o file that differs only in the
debug info line numbers.
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/e7a6acfb130471700370e77af9e4b4b6ed46f5ef.1400709717.git.luto@amacapital.netSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>