Now that we have EFI memory region bits that indicate which regions do
not need execute permission or read/write permission in the page tables,
let's use them.

We also check for EFI_NX_PE_DATA and only enforce the restrictive
mappings if it's present (to allow us to ignore buggy firmware that sets
bits it didn't mean to and to preserve backwards compatibility).

Instead of assuming that firmware would set appropriate attributes in
memory descriptor like EFI_MEMORY_RO for code and EFI_MEMORY_XP for
data, we can expect some firmware out there which might only set *type*
in memory descriptor to be EFI_RUNTIME_SERVICES_CODE or
EFI_RUNTIME_SERVICES_DATA leaving away attribute. This will lead to
improper mappings of EFI runtime regions. In order to avoid it, we check
attribute and type of memory descriptor to update mappings and moreover
Windows works this way.
Signed-off-by: NSai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: NMatt Fleming <matt@codeblueprint.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Lee, Chun-Yi <jlee@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1455712566-16727-13-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>

As part of the preparation for the EFI_MEMORY_RO flag added in the UEFI
2.5 specification, we need the ability to map pages in kernel page
tables without _PAGE_RW being set.

Modify kernel_map_pages_in_pgd() to require its callers to pass _PAGE_RW
if the pages need to be mapped read/write. Otherwise, we'll map the
pages as read-only.
Signed-off-by: NSai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: NMatt Fleming <matt@codeblueprint.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Lee, Chun-Yi <jlee@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1455712566-16727-12-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>

Since EFI page tables can be treated as kernel page tables they should
be global. All the other page mapping functions in pageattr.c set the
_PAGE_GLOBAL bit and we want to avoid inconsistencies when we map a page
in the EFI code paths, for example when that page is split in
__split_large_page(), etc. It also makes it easier to validate that the
EFI region mappings have the correct attributes because there are fewer
differences compared with regular kernel mappings.
Signed-off-by: NSai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: NMatt Fleming <matt@codeblueprint.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1455712566-16727-4-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>

Commit 3565fce3 ("mm, x86: get_user_pages() for dax mappings") has
moved up the pte_page(pte) in x86's fast gup_pte_range(), for no
discernible reason: put it back where it belongs, after the pte_flags
check and the pfn_valid cross-check.

That may be the cause of the NULL pointer dereference in
gup_pte_range(), seen when vfio called vaddr_get_pfn() when starting a
qemu-kvm based VM.
Signed-off-by: NHugh Dickins <hughd@google.com>
Reported-by: NMichael Long <Harn-Solo@gmx.de>
Tested-by: NMichael Long <Harn-Solo@gmx.de>
Acked-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A kernel page fault oops with the callstack below was observed
when a read syscall was made to a pmem device after a huge amount
(>512GB) of vmalloc ranges was allocated by ioremap() on a x86_64
system:

     BUG: unable to handle kernel paging request at ffff880840000ff8
     IP: vmalloc_fault+0x1be/0x300
     PGD c7f03a067 PUD 0
     Oops: 0000 [#1] SM
     Call Trace:
        __do_page_fault+0x285/0x3e0
        do_page_fault+0x2f/0x80
        ? put_prev_entity+0x35/0x7a0
        page_fault+0x28/0x30
        ? memcpy_erms+0x6/0x10
        ? schedule+0x35/0x80
        ? pmem_rw_bytes+0x6a/0x190 [nd_pmem]
        ? schedule_timeout+0x183/0x240
        btt_log_read+0x63/0x140 [nd_btt]
         :
        ? __symbol_put+0x60/0x60
        ? kernel_read+0x50/0x80
        SyS_finit_module+0xb9/0xf0
        entry_SYSCALL_64_fastpath+0x1a/0xa4

Since v4.1, ioremap() supports large page (pud/pmd) mappings in
x86_64 and PAE.  vmalloc_fault() however assumes that the vmalloc
range is limited to pte mappings.

vmalloc faults do not normally happen in ioremap'd ranges since
ioremap() sets up the kernel page tables, which are shared by
user processes.  pgd_ctor() sets the kernel's PGD entries to
user's during fork().  When allocation of the vmalloc ranges
crosses a 512GB boundary, ioremap() allocates a new pud table
and updates the kernel PGD entry to point it.  If user process's
PGD entry does not have this update yet, a read/write syscall
to the range will cause a vmalloc fault, which hits the Oops
above as it does not handle a large page properly.

Following changes are made to vmalloc_fault().

64-bit:

 - No change for the PGD sync operation as it handles large
   pages already.
 - Add pud_huge() and pmd_huge() to the validation code to
   handle large pages.
 - Change pud_page_vaddr() to pud_pfn() since an ioremap range
   is not directly mapped (while the if-statement still works
   with a bogus addr).
 - Change pmd_page() to pmd_pfn() since an ioremap range is not
   backed by struct page (while the if-statement still works
   with a bogus addr).

32-bit:
 - No change for the sync operation since the index3 PGD entry
   covers the entire vmalloc range, which is always valid.
   (A separate change to sync PGD entry is necessary if this
    memory layout is changed regardless of the page size.)
 - Add pmd_huge() to the validation code to handle large pages.
   This is for completeness since vmalloc_fault() won't happen
   in ioremap'd ranges as its PGD entry is always valid.
Reported-by: NHenning Schild <henning.schild@siemens.com>
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Acked-by: NBorislav Petkov <bp@alien8.de>
Cc: <stable@vger.kernel.org> # 4.1+
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-mm@kvack.org
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/1455758214-24623-1-git-send-email-toshi.kani@hpe.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Looks like the HPET spec at intel.com got moved.
It isn't hard to find so drop the link, just mention
the revision assumed.
Suggested-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/1455145462-3877-1-git-send-email-mst@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Data corruption issues were observed in tests which initiated
a system crash/reset while accessing BTT devices.  This problem
is reproducible.

The BTT driver calls pmem_rw_bytes() to update data in pmem
devices.  This interface calls __copy_user_nocache(), which
uses non-temporal stores so that the stores to pmem are
persistent.

__copy_user_nocache() uses non-temporal stores when a request
size is 8 bytes or larger (and is aligned by 8 bytes).  The
BTT driver updates the BTT map table, which entry size is
4 bytes.  Therefore, updates to the map table entries remain
cached, and are not written to pmem after a crash.

Change __copy_user_nocache() to use non-temporal store when
a request size is 4 bytes.  The change extends the current
byte-copy path for a less-than-8-bytes request, and does not
add any overhead to the regular path.
Reported-and-tested-by: NMicah Parrish <micah.parrish@hpe.com>
Reported-and-tested-by: NBrian Boylston <brian.boylston@hpe.com>
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Cc: <stable@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/1455225857-12039-3-git-send-email-toshi.kani@hpe.com
[ Small readability edits. ]
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Add comments to __copy_user_nocache() to clarify its procedures
and alignment requirements.

Also change numeric branch target labels to named local labels.

No code changed:

 arch/x86/lib/copy_user_64.o:

    text    data     bss     dec     hex filename
    1239       0       0    1239     4d7 copy_user_64.o.before
    1239       0       0    1239     4d7 copy_user_64.o.after

 md5:
    58bed94c2db98c1ca9a2d46d0680aaae  copy_user_64.o.before.asm
    58bed94c2db98c1ca9a2d46d0680aaae  copy_user_64.o.after.asm
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Cc: <stable@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: brian.boylston@hpe.com
Cc: dan.j.williams@intel.com
Cc: linux-nvdimm@lists.01.org
Cc: micah.parrish@hpe.com
Cc: ross.zwisler@linux.intel.com
Cc: vishal.l.verma@intel.com
Link: http://lkml.kernel.org/r/1455225857-12039-2-git-send-email-toshi.kani@hpe.com
[ Small readability edits and added object file comparison. ]
Signed-off-by: NIngo Molnar <mingo@kernel.org>

In the error path of amd_uncore_cpu_up_prepare() the newly allocated uncore
struct is freed, but the percpu pointer still references it. Set it to NULL.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1602162302170.19512@nanosSigned-off-by: NIngo Molnar <mingo@kernel.org>

arch/x86/built-in.o: In function `uv_bios_call':
(.text+0xeba00): undefined reference to `efi_call'
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Suggested-by: N"H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Reviewed-by: NMatt Fleming <matt@codeblueprint.co.uk>
Acked-by: NAlex Thorlton <athorlton@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The following commit:

  a0acda91 ("acpi, numa, mem_hotplug: mark all nodes the kernel resides un-hotpluggable")

Introduced numa_clear_kernel_node_hotplug(), which function is executed
during early bootup, and which marks all currently reserved memblock
regions as hot-memory-unswappable as well.

y14sg1 <y14sg1@comcast.net> reported that when running 32-bit NUMA kernels,
the grsecurity/PAX kernel patch flagged a size overflow in this function:

  PAX: size overflow detected in function x86_numa_init arch/x86/mm/numa.c:691 [...]

... the reason for the overflow is that memblock_clear_hotplug() takes physical
addresses as arguments, while the start/end variables used by
numa_clear_kernel_node_hotplug() are 'unsigned long', which is 32-bit on PAE
kernels, but which has 64-bit physical addresses.

So on 32-bit PAE kernels that have physical memory above the 4GB boundary,
we truncate a 64-bit physical address range to 32 bits and pass it to
memblock_clear_hotplug(), which at minimum prevents the original memory-hotplug
bugfix from working, but might have other side effects as well.

The fix is to use the proper type to handle physical addresses, phys_addr_t.
Reported-by: Ny14sg1 <y14sg1@comcast.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: Chen Tang <imtangchen@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Commit 944d9fec ("hugetlb: add support for gigantic page allocation
at runtime") has added the runtime gigantic page allocation via
alloc_contig_range(), making this support available only when CONFIG_CMA
is enabled.  Because it doesn't depend on MIGRATE_CMA pageblocks and the
associated infrastructure, it is possible with few simple adjustments to
require only CONFIG_MEMORY_ISOLATION instead of full CONFIG_CMA.

After this patch, alloc_contig_range() and related functions are
available and used for gigantic pages with just CONFIG_MEMORY_ISOLATION
enabled.  Note CONFIG_CMA selects CONFIG_MEMORY_ISOLATION.  This allows
supporting runtime gigantic pages without the CMA-specific checks in
page allocator fastpaths.
Signed-off-by: NVlastimil Babka <vbabka@suse.cz>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

thread_saved_pc() reads stack of a potentially running task.
This can cause false KASAN stack-out-of-bounds reports,
because the running task concurrently poisons and unpoisons
own stack.

The same happens in get_wchan(), and get get_wchan() was fixed
by using READ_ONCE_NOCHECK(). Do the same here.

Example KASAN report triggered by sysrq-t:

  BUG: KASAN: out-of-bounds in sched_show_task+0x306/0x3b0 at addr ffff880043c97c18
  Read of size 8 by task syz-executor/23839
  [...]
  page dumped because: kasan: bad access detected
  [...]
  Call Trace:
   [<ffffffff8175ea0e>] __asan_report_load8_noabort+0x3e/0x40
   [<ffffffff813e7a26>] sched_show_task+0x306/0x3b0
   [<ffffffff813e7bf4>] show_state_filter+0x124/0x1a0
   [<ffffffff82d2ca00>] fn_show_state+0x10/0x20
   [<ffffffff82d2cf98>] k_spec+0xa8/0xe0
   [<ffffffff82d3354f>] kbd_event+0xb9f/0x4000
   [<ffffffff843ca8a7>] input_to_handler+0x3a7/0x4b0
   [<ffffffff843d1954>] input_pass_values.part.5+0x554/0x6b0
   [<ffffffff843d29bc>] input_handle_event+0x2ac/0x1070
   [<ffffffff843d3a47>] input_inject_event+0x237/0x280
   [<ffffffff843e8c28>] evdev_write+0x478/0x680
   [<ffffffff817ac653>] __vfs_write+0x113/0x480
   [<ffffffff817ae0e7>] vfs_write+0x167/0x4a0
   [<ffffffff817b13d1>] SyS_write+0x111/0x220
Signed-off-by: NDmitry Vyukov <dvyukov@google.com>
Acked-by: NAndrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: glider@google.com
Cc: kasan-dev@googlegroups.com
Cc: kcc@google.com
Cc: linux-kernel@vger.kernel.org
Cc: ryabinin.a.a@gmail.com
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Adjust efi_print_memmap to print the real end address of each
range, not 1 byte beyond. This matches other prints like those
for SRAT and nosave memory.

While investigating grub persistent memory corruption issues, it
was helpful to make this table match the ending address
convention used by:
* the kernel's e820 table prints
	BIOS-e820: [mem 0x0000001680000000-0x0000001c7fffffff] reserved
* the kernel's nosave memory prints
	PM: Registered nosave memory: [mem 0x880000000-0xc7fffffff]
* the kernel's ACPI System Resource Affinity Table prints
	SRAT: Node 1 PXM 1 [mem 0x480000000-0x87fffffff]
* grub's lsmmap and lsefimmap commands
	reserved  0000001680000000-0000001c7fffffff 00600000     24GiB UC WC WT WB NV
* the UEFI shell's memmap command
	Reserved   000000007FC00000-000000007FFFFFFF 0000000000000400 0000000000000001

For example, if you grep all the various logs for c7fffffff, you
won't find the kernel's line if it uses c80000000.

Also, change the closing ) to ] to match the opening [.

old:
    efi: mem61: [Persistent Memory  |   |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000880000000-0x0000000c80000000) (16384MB)

new:
    efi: mem61: [Persistent Memory  |   |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000880000000-0x0000000c7fffffff] (16384MB)
Signed-off-by: NRobert Elliott <elliott@hpe.com>
Signed-off-by: NMatt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: NLaszlo Ersek <lersek@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1454364428-494-12-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>

Unintuitively, the BGRT graphic is apparently meant to be usable
if the valid bit in not set. The valid bit only conveys
uncertainty about the validity in relation to the screen state.

Windows 10 actually uses the BGRT image for its boot screen even
if not 'valid', for example when the user triggered the boot
menu. Because it is unclear if all firmwares will provide a
usable graphic in this case, we now look at the BMP magic number
as an additional check.
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NMôshe van der Sterre <me@moshe.nl>
Signed-off-by: NMatt Fleming <matt@codeblueprint.co.uk>
Cc: =?UTF-8?q?M=C3=B4she=20van=20der=20Sterre?= <me@moshe.nl>
Link: http://lkml.kernel.org/r/1454364428-494-10-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>

The function efi_query_variable_store() may be invoked by
efivar_entry_set_nonblocking(), which itself takes care to only
call a non-blocking version of the SetVariable() runtime
wrapper. However, efi_query_variable_store() may call the
SetVariable() wrapper directly, as well as the wrapper for
QueryVariableInfo(), both of which could deadlock in the same
way we are trying to prevent by calling
efivar_entry_set_nonblocking() in the first place.

So instead, modify efi_query_variable_store() to use the
non-blocking variants of QueryVariableInfo() (and give up rather
than free up space if the available space is below
EFI_MIN_RESERVE) if invoked with the 'nonblocking' argument set
to true.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NMatt Fleming <matt@codeblueprint.co.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1454364428-494-5-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>

There are a couple of nasty truncation bugs lurking in the pageattr
code that can be triggered when mapping EFI regions, e.g. when we pass
a cpa->pgd pointer. Because cpa->numpages is a 32-bit value, shifting
left by PAGE_SHIFT will truncate the resultant address to 32-bits.

Viorel-Cătălin managed to trigger this bug on his Dell machine that
provides a ~5GB EFI region which requires 1236992 pages to be mapped.
When calling populate_pud() the end of the region gets calculated
incorrectly in the following buggy expression,

  end = start + (cpa->numpages << PAGE_SHIFT);

And only 188416 pages are mapped. Next, populate_pud() gets invoked
for a second time because of the loop in __change_page_attr_set_clr(),
only this time no pages get mapped because shifting the remaining
number of pages (1048576) by PAGE_SHIFT is zero. At which point the
loop in __change_page_attr_set_clr() spins forever because we fail to
map progress.

Hitting this bug depends very much on the virtual address we pick to
map the large region at and how many pages we map on the initial run
through the loop. This explains why this issue was only recently hit
with the introduction of commit

  a5caa209 ("x86/efi: Fix boot crash by mapping EFI memmap
   entries bottom-up at runtime, instead of top-down")

It's interesting to note that safe uses of cpa->numpages do exist in
the pageattr code. If instead of shifting ->numpages we multiply by
PAGE_SIZE, no truncation occurs because PAGE_SIZE is a UL value, and
so the result is unsigned long.

To avoid surprises when users try to convert very large cpa->numpages
values to addresses, change the data type from 'int' to 'unsigned
long', thereby making it suitable for shifting by PAGE_SHIFT without
any type casting.

The alternative would be to make liberal use of casting, but that is
far more likely to cause problems in the future when someone adds more
code and fails to cast properly; this bug was difficult enough to
track down in the first place.
Reported-and-tested-by: NViorel-Cătălin Răpițeanu <rapiteanu.catalin@gmail.com>
Acked-by: NBorislav Petkov <bp@alien8.de>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NMatt Fleming <matt@codeblueprint.co.uk>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=110131
Link: http://lkml.kernel.org/r/1454067370-10374-1-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Get rid of the 'onln' obfuscation.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

When calling intel_alt_er() with .idx != EXTRA_REG_RSP_* we will not
initialize alt_idx and then use this uninitialized value to index an
array.

When that is not fatal, it can result in an infinite loop in its
caller __intel_shared_reg_get_constraints(), with IRQs disabled.

Alternative error modes are random memory corruption due to the
cpuc->shared_regs->regs[] array overrun, which manifest in either
get_constraints or put_constraints doing weird stuff.

Only took 6 hours of painful debugging to find this. Neither GCC nor
Smatch warnings flagged this bug.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: ae3f011f ("perf/x86/intel: Fix SLM MSR_OFFCORE_RSP1 valid_mask")
Signed-off-by: NIngo Molnar <mingo@kernel.org>

For PAE kernels "unsigned long" is not suitable to hold page protection
flags, since _PAGE_NX doesn't fit there. This is the reason for quite a
few W+X pages getting reported as insecure during boot (observed namely
for the entire initrd range).

Fixes: 281d4078 ("x86: Make page cache mode a real type")
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Reviewed-by: NJuergen Gross <JGross@suse.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/56A7635602000078000CAFF1@prv-mh.provo.novell.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

This aligns the stack pointer in chacha20_4block_xor_ssse3 to 64 bytes.
Fixes general protection faults and potential kernel panics.

Cc: stable@vger.kernel.org
Signed-off-by: NEli Cooper <elicooper@gmx.com>
Acked-by: NMartin Willi <martin@strongswan.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

__arch_wb_cache_pmem() was already an internal implementation detail of
the x86 PMEM API, but this functionality needs to be exported as part of
the general PMEM API to handle the fsync/msync case for DAX mmaps.

One thing worth noting is that we really do want this to be part of the
PMEM API as opposed to a stand-alone function like clflush_cache_range()
because of ordering restrictions.  By having wb_cache_pmem() as part of
the PMEM API we can leave it unordered, call it multiple times to write
back large amounts of memory, and then order the multiple calls with a
single wmb_pmem().
Signed-off-by: NRoss Zwisler <ross.zwisler@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Kara <jack@suse.com>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The switch to using a new dedicated page table for EFI runtime
calls in commit commit 67a9108e ("x86/efi: Build our own
page table structures") failed to take into account changes
required for the kexec code paths, which are unfortunately
duplicated in the EFI code.

Call the allocation and setup functions in
kexec_enter_virtual_mode() just like we do for
__efi_enter_virtual_mode() to avoid hitting NULL-pointer
dereferences when making EFI runtime calls.

At the very least, the call to efi_setup_page_tables() should
have existed for kexec before the following commit:

  67a9108e ("x86/efi: Build our own page table structures")

Things just magically worked because we were actually using
the kernel's page tables that contained the required mappings.
Reported-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: NMatt Fleming <matt@codeblueprint.co.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1453385519-11477-1-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>

This patch enables the uncore_imc PMU for Intel
SkyLake Desktop processors (Core i7-6700, model 94).

It is possible to compute memory read/write bandwidth
using:

  $ perf stat -a -e uncore_imc/data_reads/,uncore_imc/data_writes/ ....
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Link: http://lkml.kernel.org/r/1452151546-8853-1-git-send-email-eranian@google.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

When we print values, such as @size, we have to understand that
it's derived from [begin .. end] as:

	size = end - begin + 1

On the opposite the @end is derived from the rest as:

	end = begin + size - 1

Correct the IMR code to print values correctly.

Note that @__end_rodata actually points to the next address
after the aligned .rodata section.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ong, Boon Leong <boon.leong.ong@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1453320821-64328-1-git-send-email-andriy.shevchenko@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Move the generic implementation to <linux/dma-mapping.h> now that all
architectures support it and remove the HAVE_DMA_ATTR Kconfig symbol now
that everyone supports them.

[valentinrothberg@gmail.com: remove leftovers in Kconfig]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Helge Deller <deller@gmx.de>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NValentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

UBSAN uses compile-time instrumentation to catch undefined behavior
(UB).  Compiler inserts code that perform certain kinds of checks before
operations that could cause UB.  If check fails (i.e.  UB detected)
__ubsan_handle_* function called to print error message.

So the most of the work is done by compiler.  This patch just implements
ubsan handlers printing errors.

GCC has this capability since 4.9.x [1] (see -fsanitize=undefined
option and its suboptions).
However GCC 5.x has more checkers implemented [2].
Article [3] has a bit more details about UBSAN in the GCC.

[1] - https://gcc.gnu.org/onlinedocs/gcc-4.9.0/gcc/Debugging-Options.html
[2] - https://gcc.gnu.org/onlinedocs/gcc/Debugging-Options.html
[3] - http://developerblog.redhat.com/2014/10/16/gcc-undefined-behavior-sanitizer-ubsan/

Issues which UBSAN has found thus far are:

Found bugs:

 * out-of-bounds access - 97840cb6 ("netfilter: nfnetlink: fix
   insufficient validation in nfnetlink_bind")

undefined shifts:

 * d48458d4 ("jbd2: use a better hash function for the revoke
   table")

 * 10632008 ("clockevents: Prevent shift out of bounds")

 * 'x << -1' shift in ext4 -
   http://lkml.kernel.org/r/<5444EF21.8020501@samsung.com>

 * undefined rol32(0) -
   http://lkml.kernel.org/r/<1449198241-20654-1-git-send-email-sasha.levin@oracle.com>

 * undefined dirty_ratelimit calculation -
   http://lkml.kernel.org/r/<566594E2.3050306@odin.com>

 * undefined roundown_pow_of_two(0) -
   http://lkml.kernel.org/r/<1449156616-11474-1-git-send-email-sasha.levin@oracle.com>

 * [WONTFIX] undefined shift in __bpf_prog_run -
   http://lkml.kernel.org/r/<CACT4Y+ZxoR3UjLgcNdUm4fECLMx2VdtfrENMtRRCdgHB2n0bJA@mail.gmail.com>

   WONTFIX here because it should be fixed in bpf program, not in kernel.

signed overflows:

 * 32a8df4e ("sched: Fix odd values in effective_load()
   calculations")

 * mul overflow in ntp -
   http://lkml.kernel.org/r/<1449175608-1146-1-git-send-email-sasha.levin@oracle.com>

 * incorrect conversion into rtc_time in rtc_time64_to_tm() -
   http://lkml.kernel.org/r/<1449187944-11730-1-git-send-email-sasha.levin@oracle.com>

 * unvalidated timespec in io_getevents() -
   http://lkml.kernel.org/r/<CACT4Y+bBxVYLQ6LtOKrKtnLthqLHcw-BMp3aqP3mjdAvr9FULQ@mail.gmail.com>

 * [NOTABUG] signed overflow in ktime_add_safe() -
   http://lkml.kernel.org/r/<CACT4Y+aJ4muRnWxsUe1CMnA6P8nooO33kwG-c8YZg=0Xc8rJqw@mail.gmail.com>

[akpm@linux-foundation.org: fix unused local warning]
[akpm@linux-foundation.org: fix __int128 build woes]
Signed-off-by: NAndrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yury Gribov <y.gribov@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Move the stuff currently only used by the kexec file code within
CONFIG_KEXEC_FILE (and CONFIG_KEXEC_VERIFY_SIG).

Also move internal "struct kexec_sha_region" and "struct kexec_buf" into
"kexec_internal.h".
Signed-off-by: NXunlei Pang <xlpang@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Intel PM Telemetry is a software mechanism via which various SoC
PM and performance related parameters like PM counters, firmware
trace verbosity, the status of different devices inside the SoC, etc.
can be monitored and analyzed. The different samples that may be
monitored can be configured at runtime via exported APIs.

This patch adds the telemetry core driver that implements basic
exported APIs.
Signed-off-by: NSouvik Kumar Chakravarty <souvik.k.chakravarty@intel.com>
Signed-off-by: NDarren Hart <dvhart@linux.intel.com>

This driver provides support for P-Unit mailbox IPC on Intel platforms.
The heart of the P-Unit is the Foxton microcontroller and its firmware,
which provide mailbox interface for power management usage.
Signed-off-by: NQipeng Zha <qipeng.zha@intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NDarren Hart <dvhart@linux.intel.com>

Commit a5d90c92 ("x86/efi: Quirk out SGI UV") added a quirk
to efi_apply_memmap_quirks to force SGI UV systems to fall back
to the old EFI memmap mechanism.  We have a BIOS fix for this
issue on all systems except for UV1.  This commit fixes up the
EFI quirk/MMR mapping code so that we only apply the special
case to UV1 hardware.
Signed-off-by: NAlex Thorlton <athorlton@sgi.com>
Reviewed-by: NMatt Fleming <matt@codeblueprint.co.uk>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hedi Berriche <hedi@sgi.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Travis <travis@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1449867585-189233-2-git-send-email-athorlton@sgi.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Join string back to make grepping a bit easier. While here,
lowering case for Penwell SoC name in one case to be aligned
with the rest messages.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1452888668-147116-2-git-send-email-andriy.shevchenko@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Intel Tangier SoC is known to have 64-bit dual core CPU. Enable
64-bit build for it.

The kernel has been tested on Intel Edison board:

	Linux buildroot 4.4.0-next-20160115+ #25 SMP Fri Jan 15 22:03:19 EET 2016 x86_64 GNU/Linux

	processor       : 0
	vendor_id       : GenuineIntel
	cpu family      : 6
	model           : 74
	model name      : Genuine Intel(R) CPU   4000  @  500MHz
	stepping        : 8
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1452888668-147116-1-git-send-email-andriy.shevchenko@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

If anyone includes asm/livepatch.h when CONFIG_LIVEPATCH=n the build
fails with the existing error message. Change it to something saner.

[jkosina@suse.cz: fixed changelog typo spotted by Josh]
Suggested-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NMiroslav Benes <mbenes@suse.cz>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

As illustrated by commit a3afe70b ("[S390] latencytop s390
support."), HAVE_LATENCYTOP_SUPPORT is defined by an architecture to
advertise an implementation of save_stack_trace_tsk.

However, as of 9212ddb5 ("stacktrace: provide save_stack_trace_tsk()
weak alias") a dummy implementation is provided if STACKTRACE=y.  Given
that LATENCYTOP already depends on STACKTRACE_SUPPORT and selects
STACKTRACE, we can remove HAVE_LATENCYTOP_SUPPORT altogether.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Helge Deller <deller@gmx.de>
Acked-by: NMichael Ellerman <mpe@ellerman.id.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A dax mapping establishes a pte with _PAGE_DEVMAP set when the driver
has established a devm_memremap_pages() mapping, i.e.  when the pfn_t
return from ->direct_access() has PFN_DEV and PFN_MAP set.  Later, when
encountering _PAGE_DEVMAP during a page table walk we lookup and pin a
struct dev_pagemap instance to keep the result of pfn_to_page() valid
until put_page().
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Tested-by: NLogan Gunthorpe <logang@deltatee.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
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>

A dax-huge-page mapping while it uses some thp helpers is ultimately not
a transparent huge page.  The distinction is especially important in the
get_user_pages() path.  pmd_devmap() is used to distinguish dax-pmds
from pmd_huge() and pmd_trans_huge() which have slightly different
semantics.

Explicitly mark the pmd_trans_huge() helpers that dax needs by adding
pmd_devmap() checks.

[kirill.shutemov@linux.intel.com: fix regression in handling mlocked pages in  __split_huge_pmd()]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Similar to the conversion of vm_insert_mixed() use pfn_t in the
vmf_insert_pfn_pmd() to tag the resulting pte with _PAGE_DEVICE when the
pfn is backed by a devm_memremap_pages() mapping.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Convert the raw unsigned long 'pfn' argument to pfn_t for the purpose of
evaluating the PFN_MAP and PFN_DEV flags.  When both are set it triggers
_PAGE_DEVMAP to be set in the resulting pte.

There are no functional changes to the gpu drivers as a result of this
conversion.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

_PAGE_DEVMAP is a hardware-unused pte bit that will later be used in the
get_user_pages() path to identify pfns backed by the dynamic allocation
established by devm_memremap_pages.  Upon seeing that bit the gup path
will lookup and pin the allocation while the pages are in use.

Since the _PAGE_DEVMAP bit is > 32 it must be cast to u64 instead of a
pteval_t to allow pmd_flags() usage in the realmode boot code to build.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
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>