Depending on configuration mem_section can now be an array or a pointer
to an array allocated dynamically. In most cases, we can continue to refer
to it as 'mem_section' regardless of what it is.

But there's one exception: '&mem_section' means "address of the array" if
mem_section is an array, but if mem_section is a pointer, it would mean
"address of the pointer".

We've stepped onto this in the kdump code: VMCOREINFO_SYMBOL(mem_section)
writes down the address of pointer into vmcoreinfo, not the array as we wanted,
breaking kdump.

Let's introduce VMCOREINFO_SYMBOL_ARRAY() that would handle the
situation correctly for both cases.

Mike Galbraith <efault@gmx.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: kexec@lists.infradead.org
Cc: linux-mm@kvack.org
Cc: stable@vger.kernel.org
Fixes: 83e3c487 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y")
Link: http://lkml.kernel.org/r/20180112162532.35896-1-kirill.shutemov@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

So one of the constification patches unearthed a type casting fragility
of the underlying code:

  276c8705 ("x86/platform/intel-mid: Make 'bt_sfi_data' const")

converted the struct to be const while it is also used as a temporary
container for important data that is used to fill 'parent' and 'name'
fields in struct platform_device_info.

The compiler doesn't notice this due to an explicit type cast that loses
the const - which fragility will be fixed separately.

This type cast turned a seemingly trivial const propagation patch into a
hard to debug data corruptor and crasher bug.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bhumika Goyal <bhumirks@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: julia.lawall@lip6.fr
Cc: platform-driver-x86@vger.kernel.org
Link: http://lkml.kernel.org/r/20171228122523.21802-1-andriy.shevchenko@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Instead of blacklisting all model 79 CPUs when attempting a late
microcode loading, limit that only to CPUs with microcode revisions <
0x0b000021 because only on those late loading may cause a system hang.

For such processors either:

a) a BIOS update which might contain a newer microcode revision

or

b) the early microcode loading method

should be considered.

Processors with revisions 0x0b000021 or higher will not experience such
hangs.

For more details, see erratum BDF90 in document #334165 (Intel Xeon
Processor E7-8800/4800 v4 Product Family Specification Update) from
September 2017.

[ bp: Heavily massage commit message and pr_* statements. ]

Fixes: 723f2828 ("x86/microcode/intel: Disable late loading on model 79")
Signed-off-by: Jia Zhang <qianyue.zj@alibaba-inc.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Cc: <stable@vger.kernel.org> # v4.14
Link: http://lkml.kernel.org/r/1514772287-92959-1-git-send-email-qianyue.zj@alibaba-inc.com

Pull btrfs fixes from David Sterba:
 "We have two more fixes for 4.15, both aimed for stable.

  The leak fix is obvious, the second patch fixes a bug revealed by the
  refcount API, when it behaves differently than previous atomic_t and
  reports refs going from 0 to 1 in one case"

* tag 'for-4.15-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix refcount_t usage when deleting btrfs_delayed_nodes
  btrfs: Fix flush bio leak

Pull XFS fixes from Darrick Wong:
 "I have just a few fixes for bugs and resource cleanup problems this
  week:

   - Fix resource cleanup of failed quota initialization

   - Fix integer overflow problems wrt s_maxbytes"

* tag 'xfs-4.15-fixes-10' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: fix s_maxbytes overflow problems
  xfs: quota: check result of register_shrinker()
  xfs: quota: fix missed destroy of qi_tree_lock

Pull MFD fix from Lee Jones:
 "Late bugfix to plug a leak in rtsx_pcr"

* tag 'mfd-fixes-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd:
  mfd: rtsx: Release IRQ during shutdown

Pull  more x86 pti fixes from Thomas Gleixner:
 "Another small stash of fixes for fallout from the PTI work:

   - Fix the modules vs. KASAN breakage which was caused by making
     MODULES_END depend of the fixmap size. That was done when the cpu
     entry area moved into the fixmap, but now that we have a separate
     map space for that this is causing more issues than it solves.

   - Use the proper cache flush methods for the debugstore buffers as
     they are mapped/unmapped during runtime and not statically mapped
     at boot time like the rest of the cpu entry area.

   - Make the map layout of the cpu_entry_area consistent for 4 and 5
     level paging and fix the KASLR vaddr_end wreckage.

   - Use PER_CPU_EXPORT for per cpu variable and while at it unbreak
     nvidia gfx drivers by dropping the GPL export. The subject line of
     the commit tells it the other way around, but I noticed that too
     late.

   - Fix the ASM alternative macros so they can be used in the middle of
     an inline asm block.

   - Rename the BUG_CPU_INSECURE flag to BUG_CPU_MELTDOWN so the attack
     vector is properly identified. The Spectre mitigations will come
     with their own bug bits later"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/pti: Rename BUG_CPU_INSECURE to BUG_CPU_MELTDOWN
  x86/alternatives: Add missing '\n' at end of ALTERNATIVE inline asm
  x86/tlb: Drop the _GPL from the cpu_tlbstate export
  x86/events/intel/ds: Use the proper cache flush method for mapping ds buffers
  x86/kaslr: Fix the vaddr_end mess
  x86/mm: Map cpu_entry_area at the same place on 4/5 level
  x86/mm: Set MODULES_END to 0xffffffffff000000

Pull EFI updates from Thomas Gleixner:

 - A fix for a add_efi_memmap parameter regression which ensures that
   the parameter is parsed before it is used.

 - Reinstate the virtual capsule mapping as the cached copy turned out
   to break Quark and other things

 - Remove Matt Fleming as EFI co-maintainer. He stepped back a few days
   ago. Thanks Matt for all your great work!

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  MAINTAINERS: Remove Matt Fleming as EFI co-maintainer
  efi/capsule-loader: Reinstate virtual capsule mapping
  x86/efi: Fix kernel param add_efi_memmap regression

Pull s390 fixes from Martin Schwidefsky:
 "Four bug fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/dasd: fix wrongly assigned configuration data
  s390: fix preemption race in disable_sacf_uaccess
  s390/sclp: disable FORTIFY_SOURCE for early sclp code
  s390/pci: handle insufficient resources during dma tlb flush

Pull xen fix from Juergen Gross:
 "One minor fix adjusting the kmalloc flags in the new pvcalls driver
  added in rc1"

* tag 'for-linus-4.15-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/pvcalls: use GFP_ATOMIC under spin lock

Pull crypto fixes from Herbert Xu:
 "This fixes the following issues:

   - racy use of ctx->rcvused in af_alg

   - algif_aead crash in chacha20poly1305

   - freeing bogus pointer in pcrypt

   - build error on MIPS in mpi

   - memory leak in inside-secure

   - memory overwrite in inside-secure

   - NULL pointer dereference in inside-secure

   - state corruption in inside-secure

   - build error without CRYPTO_GF128MUL in chelsio

   - use after free in n2"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: inside-secure - do not use areq->result for partial results
  crypto: inside-secure - fix request allocations in invalidation path
  crypto: inside-secure - free requests even if their handling failed
  crypto: inside-secure - per request invalidation
  lib/mpi: Fix umul_ppmm() for MIPS64r6
  crypto: pcrypt - fix freeing pcrypt instances
  crypto: n2 - cure use after free
  crypto: af_alg - Fix race around ctx->rcvused by making it atomic_t
  crypto: chacha20poly1305 - validate the digest size
  crypto: chelsio - select CRYPTO_GF128MUL

Merge misc fixes from Andrew Morton:
 "9 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mailmap: update Mark Yao's email address
  userfaultfd: clear the vma->vm_userfaultfd_ctx if UFFD_EVENT_FORK fails
  mm/sparse.c: wrong allocation for mem_section
  mm/zsmalloc.c: include fs.h
  mm/debug.c: provide useful debugging information for VM_BUG
  kernel/exit.c: export abort() to modules
  mm/mprotect: add a cond_resched() inside change_pmd_range()
  kernel/acct.c: fix the acct->needcheck check in check_free_space()
  mm: check pfn_valid first in zero_resv_unavail

Use the name associated with the particular attack which needs page table
isolation for mitigation.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc: Jiri Koshina <jikos@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Lutomirski  <luto@amacapital.net>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Turner <pjt@google.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Greg KH <gregkh@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801051525300.1724@nanos

Where an ALTERNATIVE is used in the middle of an inline asm block, this
would otherwise lead to the following instruction being appended directly
to the trailing ".popsection", and a failed compile.

Fixes: 9cebed42 ("x86, alternative: Use .pushsection/.popsection")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: ak@linux.intel.com
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Turner <pjt@google.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180104143710.8961-8-dwmw@amazon.co.uk

'Commit cc27b735 ("PCI/portdrv: Turn off PCIe services during
shutdown")' revealed a resource leak in rtsx_pci driver during shutdown.

Issue shows up as a warning during shutdown as follows:

remove_proc_entry: removing non-empty directory 'irq/17', leaking at least
'rtsx_pci'
WARNING: CPU: 0 PID: 1578 at fs/proc/generic.c:572
remove_proc_entry+0x11d/0x130
Modules linked in <long list but none that are out-of-tree>
...
Call Trace:
unregister_irq_proc
free_desc
irq_free_descs
mp_unmap_irq
acpi_unregister_gsi_apic
acpi_pci_irq_disable
do_pci_disable_device
pci_disable_device
device_shutdown
kernel_restart
Sys_reboot

Even though rtsx_pci driver implements a shutdown callback, it is not
releasing the interrupt that it registered during probe. This is causing
the ACPI layer to complain that the shared IRQ is in use while freeing
IRQ.

This code releases the IRQ to prevent resource leak and eliminate the
warning.

Fixes: cc27b735 ("PCI/portdrv: Turn off PCIe services during shutdown")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=198141Reported-by: Chris Clayton <chris2553@googlemail.com>
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Pull drm fixes from Dave Airlie:
 "Just collecting some fixes to finish my hoildays :-).

  A few fixes for i915 (one documentation build fix), one ttm fix, one
  AMD display fix, one omapdrm fix, and a set of armada fixes from
  Russell.

  All seem pretty small, you can now return to your latest security news
  site"

* tag 'drm-fixes-for-v4.15-rc7' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: Apply Display WA #1183 on skl, kbl, and cfl
  drm/ttm: check the return value of kzalloc
  drm/amd/display: call set csc_default if enable adjustment is false
  docs: fix, intel_guc_loader.c has been moved to intel_guc_fw.c
  omapdrm/dss/hdmi4_cec: fix interrupt handling
  documentation/gpu/i915: fix docs build error after file rename
  drm/i915: Put all non-blocking modesets onto an ordered wq
  drm/i915: Disable DC states around GMBUS on GLK
  drm/i915/psr: Fix register name mess up.
  drm/armada: fix YUV planar format framebuffer offsets
  drm/armada: improve efficiency of armada_drm_plane_calc_addrs()
  drm/armada: fix UV swap code
  drm/armada: fix SRAM powerdown
  drm/armada: fix leak of crtc structure

Change the previous employers email addresses to the current email
address.

Link: http://lkml.kernel.org/r/20171229121726.31589-1-jeffy.chen@rock-chips.comSigned-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Acked-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The previous fix in commit 384632e6 ("userfaultfd: non-cooperative:
fix fork use after free") corrected the refcounting in case of
UFFD_EVENT_FORK failure for the fork userfault paths.

That still didn't clear the vma->vm_userfaultfd_ctx of the vmas that
were set to point to the aborted new uffd ctx earlier in
dup_userfaultfd.

Link: http://lkml.kernel.org/r/20171223002505.593-2-aarcange@redhat.comSigned-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In commit 83e3c487 ("mm/sparsemem: Allocate mem_section at runtime
for CONFIG_SPARSEMEM_EXTREME=y") mem_section is allocated at runtime to
save memory.

It allocates the first dimension of array with sizeof(struct mem_section).

It costs extra memory, should be sizeof(struct mem_section *).

Fix it.

Link: http://lkml.kernel.org/r/1513932498-20350-1-git-send-email-bhe@redhat.com
Fixes: 83e3c487 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y")
Signed-off-by: Baoquan He <bhe@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

`struct file_system_type' and alloc_anon_inode() function are defined in
fs.h, include it directly.

Link: http://lkml.kernel.org/r/20171219104219.3017-1-sergey.senozhatsky@gmail.comSigned-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With the recent addition of hashed kernel pointers, places which need to
produce useful debug output have to specify %px, not %p.  This patch
fixes all the VM debug to use %px.  This is appropriate because it's
debug output that the user should never be able to trigger, and kernel
developers need to see the actual pointers.

Link: http://lkml.kernel.org/r/20171219133236.GE13680@bombadil.infradead.orgSigned-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: "Tobin C. Harding" <me@tobin.cc>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

gcc -fisolate-erroneous-paths-dereference can generate calls to abort()
from modular code too.

[arnd@arndb.de: drop duplicate exports of abort()]
  Link: http://lkml.kernel.org/r/20180102103311.706364-1-arnd@arndb.deReported-by: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Jose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

While testing on a large CPU system, detected the following RCU stall
many times over the span of the workload.  This problem is solved by
adding a cond_resched() in the change_pmd_range() function.

  INFO: rcu_sched detected stalls on CPUs/tasks:
   154-....: (670 ticks this GP) idle=022/140000000000000/0 softirq=2825/2825 fqs=612
   (detected by 955, t=6002 jiffies, g=4486, c=4485, q=90864)
  Sending NMI from CPU 955 to CPUs 154:
  NMI backtrace for cpu 154
  CPU: 154 PID: 147071 Comm: workload Not tainted 4.15.0-rc3+ #3
  NIP:  c0000000000b3f64 LR: c0000000000b33d4 CTR: 000000000000aa18
  REGS: 00000000a4b0fb44 TRAP: 0501   Not tainted  (4.15.0-rc3+)
  MSR:  8000000000009033 <SF,EE,ME,IR,DR,RI,LE>  CR: 22422082  XER: 00000000
  CFAR: 00000000006cf8f0 SOFTE: 1
  GPR00: 0010000000000000 c00003ef9b1cb8c0 c0000000010cc600 0000000000000000
  GPR04: 8e0000018c32b200 40017b3858fd6e00 8e0000018c32b208 40017b3858fd6e00
  GPR08: 8e0000018c32b210 40017b3858fd6e00 8e0000018c32b218 40017b3858fd6e00
  GPR12: ffffffffffffffff c00000000fb25100
  NIP [c0000000000b3f64] plpar_hcall9+0x44/0x7c
  LR [c0000000000b33d4] pSeries_lpar_flush_hash_range+0x384/0x420
  Call Trace:
    flush_hash_range+0x48/0x100
    __flush_tlb_pending+0x44/0xd0
    hpte_need_flush+0x408/0x470
    change_protection_range+0xaac/0xf10
    change_prot_numa+0x30/0xb0
    task_numa_work+0x2d0/0x3e0
    task_work_run+0x130/0x190
    do_notify_resume+0x118/0x120
    ret_from_except_lite+0x70/0x74
  Instruction dump:
  60000000 f8810028 7ca42b78 7cc53378 7ce63b78 7d074378 7d284b78 7d495378
  e9410060 e9610068 e9810070 44000022 <7d806378> e9810028 f88c0000 f8ac0008

Link: http://lkml.kernel.org/r/20171214140551.5794-1-khandual@linux.vnet.ibm.comSigned-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

As Tsukada explains, the time_is_before_jiffies(acct->needcheck) check
is very wrong, we need time_is_after_jiffies() to make sys_acct() work.

Ignoring the overflows, the code should "goto out" if needcheck >
jiffies, while currently it checks "needcheck < jiffies" and thus in the
likely case check_free_space() does nothing until jiffies overflow.

In particular this means that sys_acct() is simply broken, acct_on()
sets acct->needcheck = jiffies and expects that check_free_space()
should set acct->active = 1 after the free-space check, but this won't
happen if jiffies increments in between.

This was broken by commit 32dc7308 ("get rid of timer in
kern/acct.c") in 2011, then another (correct) commit 795a2f22
("acct() should honour the limits from the very beginning") made the
problem more visible.

Link: http://lkml.kernel.org/r/20171213133940.GA6554@redhat.com
Fixes: 32dc7308 ("get rid of timer in kern/acct.c")
Reported-by: TSUKADA Koutaro <tsukada@ascade.co.jp>
Suggested-by: TSUKADA Koutaro <tsukada@ascade.co.jp>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With latest kernel I get below bug while testing kdump:

  BUG: unable to handle kernel paging request at ffffea00034b1040
  IP: zero_resv_unavail+0xbd/0x126
  PGD 37b98067 P4D 37b98067 PUD 37b97067 PMD 0
  Oops: 0002 [#1] SMP
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper Not tainted 4.15.0-rc1+ #316
  Hardware name: LENOVO 20ARS1BJ02/20ARS1BJ02, BIOS GJET92WW (2.42 ) 03/03/2017
  task: ffffffff81a0e4c0 task.stack: ffffffff81a00000
  RIP: 0010:zero_resv_unavail+0xbd/0x126
  RSP: 0000:ffffffff81a03d88 EFLAGS: 00010006
  RAX: 0000000000000000 RBX: ffffea00034b1040 RCX: 0000000000000010
  RDX: 0000000000000000 RSI: 0000000000000092 RDI: ffffea00034b1040
  RBP: 00000000000d2c41 R08: 00000000000000c0 R09: 0000000000000a0d
  R10: 0000000000000002 R11: 0000000000007f01 R12: ffffffff81a03d90
  R13: ffffea0000000000 R14: 0000000000000063 R15: 0000000000000062
  FS:  0000000000000000(0000) GS:ffffffff81c73000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: ffffea00034b1040 CR3: 0000000037609000 CR4: 00000000000606b0
  Call Trace:
   ? free_area_init_nodes+0x640/0x664
   ? zone_sizes_init+0x58/0x72
   ? setup_arch+0xb50/0xc6c
   ? start_kernel+0x64/0x43d
   ? secondary_startup_64+0xa5/0xb0
  Code: c1 e8 0c 48 39 d8 76 27 48 89 de 48 c1 e3 06 48 c7 c7 7a 87 79 81 e8 b0 c0 3e ff 4c 01 eb b9 10 00 00 00 31 c0 48 89 df 49 ff c6 <f3> ab eb bc 6a 00 49 c7 c0 f0 93 d1 81 31 d2 83 ce ff 41 54 49
  RIP: zero_resv_unavail+0xbd/0x126 RSP: ffffffff81a03d88
  CR2: ffffea00034b1040
  ---[ end trace f5ba9e8f73c7ee26 ]---

This is introduced by commit a4a3ede2 ("mm: zero reserved and
unavailable struct pages").

The reason is some efi reserved boot ranges is not reported in E820 ram.
In my case it is a bgrt buffer:

  efi: mem00: [Boot Data          |RUN|  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x00000000d2c41000-0x00000000d2c85fff] (0MB)

Use "add_efi_memmap" can workaround the problem with another fix:

  http://lkml.kernel.org/r/20171130052327.GA3500@dhcp-128-65.nay.redhat.com

In zero_resv_unavail it would be better to check pfn_valid first before
zero the page struct.  This fixes the problem and potential other
similar problems.  Also as Pavel Tatashin suggested checks pfn_valid at
the beginning of the section.

The range is backed by real memory.  The memory range is efi "Boot
Service Data", that means after ExitBootServices() these ranges can be
used as system ram.  But some of them need to be reserved, for example
the bgrt image address in an acpi table, if the image memory is freed
then kexec reboot will fail because kexec inherit same acpi table to
initialize the driver.

Link: http://lkml.kernel.org/r/20171201095048.GA3084@dhcp-128-65.nay.redhat.com
Fixes: a4a3ede2 ("mm: zero reserved and unavailable struct pages")
Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The recent changes for PTI touch cpu_tlbstate from various tlb_flush
inlines. cpu_tlbstate is exported as GPL symbol, so this causes a
regression when building out of tree drivers for certain graphics cards.

Aside of that the export was wrong since it was introduced as it should
have been EXPORT_PER_CPU_SYMBOL_GPL().

Use the correct PER_CPU export and drop the _GPL to restore the previous
state which allows users to utilize the cards they payed for.

As always I'm really thrilled to make this kind of change to support the
#friends (or however the hot hashtag of today is spelled) from that closet
sauce graphics corp.

Fixes: 1e02ce4c ("x86: Store a per-cpu shadow copy of CR4")
Fixes: 6fd166aa ("x86/mm: Use/Fix PCID to optimize user/kernel switches")
Reported-by: Kees Cook <keescook@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: stable@vger.kernel.org

Thomas reported the following warning:

 BUG: using smp_processor_id() in preemptible [00000000] code: ovsdb-server/4498
 caller is native_flush_tlb_single+0x57/0xc0
 native_flush_tlb_single+0x57/0xc0
 __set_pte_vaddr+0x2d/0x40
 set_pte_vaddr+0x2f/0x40
 cea_set_pte+0x30/0x40
 ds_update_cea.constprop.4+0x4d/0x70
 reserve_ds_buffers+0x159/0x410
 x86_reserve_hardware+0x150/0x160
 x86_pmu_event_init+0x3e/0x1f0
 perf_try_init_event+0x69/0x80
 perf_event_alloc+0x652/0x740
 SyS_perf_event_open+0x3f6/0xd60
 do_syscall_64+0x5c/0x190

set_pte_vaddr is used to map the ds buffers into the cpu entry area, but
there are two problems with that:

 1) The resulting flush is not supposed to be called in preemptible context

 2) The cpu entry area is supposed to be per CPU, but the debug store
    buffers are mapped for all CPUs so these mappings need to be flushed
    globally.

Add the necessary preemption protection across the mapping code and flush
TLBs globally.

Fixes: c1961a46 ("x86/events/intel/ds: Map debug buffers in cpu_entry_area")
Reported-by: Thomas Zeitlhofer <thomas.zeitlhofer+lkml@ze-it.at>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Thomas Zeitlhofer <thomas.zeitlhofer+lkml@ze-it.at>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180104170712.GB3040@hirez.programming.kicks-ass.net

vaddr_end for KASLR is only documented in the KASLR code itself and is
adjusted depending on config options. So it's not surprising that a change
of the memory layout causes KASLR to have the wrong vaddr_end. This can map
arbitrary stuff into other areas causing hard to understand problems.

Remove the whole ifdef magic and define the start of the cpu_entry_area to
be the end of the KASLR vaddr range.

Add documentation to that effect.

Fixes: 92a0f81d ("x86/cpu_entry_area: Move it out of the fixmap")
Reported-by: Benjamin Gilbert <benjamin.gilbert@coreos.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Benjamin Gilbert <benjamin.gilbert@coreos.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable <stable@vger.kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>,
Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801041320360.1771@nanos

Merge tag 'drm-intel-fixes-2018-01-04' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

drm/i915 fixes for v4.15-rc7
- couple of documentation build fixes
- serialize non-blocking modesets
- prevent DMC from messing up GMBUS transfers
- PSR regression fix

* tag 'drm-intel-fixes-2018-01-04' of git://anongit.freedesktop.org/drm/drm-intel:
  drm/i915: Apply Display WA #1183 on skl, kbl, and cfl
  docs: fix, intel_guc_loader.c has been moved to intel_guc_fw.c
  documentation/gpu/i915: fix docs build error after file rename
  drm/i915: Put all non-blocking modesets onto an ordered wq
  drm/i915: Disable DC states around GMBUS on GLK
  drm/i915/psr: Fix register name mess up.

- backport of a DC change which fixes a greenish tint on some RV hw
- properly handle kzalloc fail in ttm

* 'drm-fixes-4.15' of git://people.freedesktop.org/~agd5f/linux:
  drm/ttm: check the return value of kzalloc
  drm/amd/display: call set csc_default if enable adjustment is false

Armada fixes.

* 'drm-armada-fixes-4.15' of git://git.armlinux.org.uk/~rmk/linux-arm:
  drm/armada: fix YUV planar format framebuffer offsets
  drm/armada: improve efficiency of armada_drm_plane_calc_addrs()
  drm/armada: fix UV swap code
  drm/armada: fix SRAM powerdown
  drm/armada: fix leak of crtc structure

Merge tag 'omapdrm-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux into drm-fixes

omapdrm fixes for 4.15

* Fix OMAP4 HDMI CEC interrupt handling and a possible buffer overflow

* tag 'omapdrm-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux:
  omapdrm/dss/hdmi4_cec: fix interrupt handling

There is no reason for 4 and 5 level pagetables to have a different
layout. It just makes determining vaddr_end for KASLR harder than
necessary.

Fixes: 92a0f81d ("x86/cpu_entry_area: Move it out of the fixmap")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Gilbert <benjamin.gilbert@coreos.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable <stable@vger.kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>,
Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801041320360.1771@nanos

Since f06bdd40 ("x86/mm: Adapt MODULES_END based on fixmap section size")
kasan_mem_to_shadow(MODULES_END) could be not aligned to a page boundary.

So passing page unaligned address to kasan_populate_zero_shadow() have two
possible effects:

1) It may leave one page hole in supposed to be populated area. After commit
  21506525 ("x86/kasan/64: Teach KASAN about the cpu_entry_area") that
  hole happens to be in the shadow covering fixmap area and leads to crash:

 BUG: unable to handle kernel paging request at fffffbffffe8ee04
 RIP: 0010:check_memory_region+0x5c/0x190

 Call Trace:
  <NMI>
  memcpy+0x1f/0x50
  ghes_copy_tofrom_phys+0xab/0x180
  ghes_read_estatus+0xfb/0x280
  ghes_notify_nmi+0x2b2/0x410
  nmi_handle+0x115/0x2c0
  default_do_nmi+0x57/0x110
  do_nmi+0xf8/0x150
  end_repeat_nmi+0x1a/0x1e

Note, the crash likely disappeared after commit 92a0f81d, which
changed kasan_populate_zero_shadow() call the way it was before
commit 21506525.

2) Attempt to load module near MODULES_END will fail, because
   __vmalloc_node_range() called from kasan_module_alloc() will hit the
   WARN_ON(!pte_none(*pte)) in the vmap_pte_range() and bail out with error.

To fix this we need to make kasan_mem_to_shadow(MODULES_END) page aligned
which means that MODULES_END should be 8*PAGE_SIZE aligned.

The whole point of commit f06bdd40 was to move MODULES_END down if
NR_CPUS is big, so the cpu_entry_area takes a lot of space.
But since 92a0f81d ("x86/cpu_entry_area: Move it out of the fixmap")
the cpu_entry_area is no longer in fixmap, so we could just set
MODULES_END to a fixed 8*PAGE_SIZE aligned address.

Fixes: f06bdd40 ("x86/mm: Adapt MODULES_END based on fixmap section size")
Reported-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Garnier <thgarnie@google.com>
Link: https://lkml.kernel.org/r/20171228160620.23818-1-aryabinin@virtuozzo.com

Pull ARM SoC fixes from Arnd Bergmann:
 "Fixes this time include mostly device tree changes, as usual, the
  notable ones include:

   - A number of patches to fix most of the remaining DTC warnings that
     got introduced when DTC started warning about some obvious
     mistakes. We still have some remaining warnings that probably may
     have to wait until 4.16 to get fixed while we try to figure out
     what the correct contents should be.

   - On Allwinner A64, Ethernet PHYs need a fix after a mistake in
     coordination between patches merged through multiple branches.

   - Various fixes for PMICs on allwinner based boards

   - Two fixes for ethernet link detection on some Renesas machines

   - Two stability fixes for rockchip based boards

  Aside from device-tree, two other areas got fixes for older problems:

   - For TI Davinci DM365, a couple of fixes were needed to repair the
     MMC DMA engine support, apparently this has been broken for a
     while.

   - One important fix for all Allwinner chips with the PMIC driver as a
     loadable module"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (23 commits)
  arm64: dts: uniphier: fix gpio-ranges property of PXs3 SoC
  arm64: dts: renesas: ulcb: Remove renesas, no-ether-link property
  arm64: dts: renesas: salvator-x: Remove renesas, no-ether-link property
  ARM: dts: tango4: remove bogus interrupt-controller property
  ARM: dts: ls1021a: fix incorrect clock references
  ARM: dts: aspeed-g4: Correct VUART IRQ number
  ARM: dts: exynos: Enable Mixer node for Exynos5800 Peach Pi machine
  ARM: dts: sun8i: a711: Reinstate the PMIC compatible
  ARM: davinci: fix mmc entries in dm365's dma_slave_map
  ARM: dts: da850-lego-ev3: Fix battery voltage gpio
  ARM: davinci: Add dma_mask to dm365's eDMA device
  ARM: davinci: Use platform_device_register_full() to create pdev for dm365's eDMA
  arm64: dts: rockchip: limit rk3328-rock64 gmac speed to 100MBit for now
  arm64: dts: rockchip: remove vdd_log from rk3399-puma
  arm64: dts: orange-pi-zero-plus2: fix sdcard detect
  arm64: allwinner: a64-sopine: Fix to use dcdc1 regulator instead of vcc3v3
  ARM: dts: sunxi: Convert to CCU index macros for HDMI controller
  sunxi-rsb: Include OF based modalias in device uevent
  ARM: dts: at91: disable the nxp,se97b SMBUS timeout on the TSE-850
  arm64: dts: rockchip: fix trailing 0 in rk3328 tsadc interrupts
  ...

This is probably a copy-paste mistake.  The gpio-ranges of PXs3 is
different from that of LD20.

Fixes: 277b51e7 ("arm64: dts: uniphier: add GPIO controller nodes")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Merge tag 'sunxi-fixes-for-4.15' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/sunxi/linux into fixes

Pull "Allwinner fixes for 4.15" from Chen-Yu Tsai:

First, one fix that adds proper regulator references for the EMAC
external PHYs on A64 boards. The EMAC bindings were developed for 4.13,
but reverted at the last minute. They were finalized and brought back
for 4.15. However in the time between, regulator support for the A64
boards was merged. When EMAC device tree changes were reintroduced,
this was not taken into account.

Second, a patch that adds OF based modalias uevent for RSB slave devices.
This has been missing since the introduction of RSB, and recently with
PMIC regulator support introduced for the A64, has been seen affecting
distributions, which have the all-important PMIC mfd drivers built as
modules, which then don't get loaded.

Other minor cleanups include final conversion of raw indices to CCU
binding macros for sun[4567]i HDMI, cleanup of dummy regulators on the
A64 SOPINE, a SD card detection polarity fix for the Orange Pi Zero
Plus2, and adding a missing compatible for the PMIC on the TBS A711
tablet.

* tag 'sunxi-fixes-for-4.15' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/sunxi/linux:
  ARM: dts: sun8i: a711: Reinstate the PMIC compatible
  arm64: dts: orange-pi-zero-plus2: fix sdcard detect
  arm64: allwinner: a64-sopine: Fix to use dcdc1 regulator instead of vcc3v3
  ARM: dts: sunxi: Convert to CCU index macros for HDMI controller
  sunxi-rsb: Include OF based modalias in device uevent
  arm64: allwinner: a64: add Ethernet PHY regulator for several boards

Merge tag 'renesas-fixes-for-v4.15' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/horms/renesas into fixes

Pull "Renesas ARM Based SoC Fixes for v4.15" from Simon Horman:

Vladimir Zapolskiy says:

The present change is a bug fix for AVB link iteratively up/down.

Steps to reproduce:
- start AVB TX stream (Using aplay via MSE),
- disconnect+reconnect the eth cable,
- after a reconnection the eth connection goes iteratively up/down
  without user interaction,
- this may heal after some seconds or even stay for minutes.

As the documentation specifies, the "renesas,no-ether-link" option
should be used when a board does not provide a proper AVB_LINK signal.
There is no need for this option enabled on RCAR H3/M3 Salvator-X/XS
and ULCB starter kits since the AVB_LINK is correctly handled by HW.

Choosing to keep or remove the "renesas,no-ether-link" option will
have impact on the code flow in the following ways:
- keeping this option enabled may lead to unexpected behavior since
  the RX & TX are enabled/disabled directly from adjust_link function
  without any HW interrogation,
- removing this option, the RX & TX will only be enabled/disabled after
  HW interrogation. The HW check is made through the LMON pin in PSR
  register which specifies AVB_LINK signal value (0 - at low level;
  1 - at high level).

In conclusion, the change is also a safety improvement because it
removes the "renesas,no-ether-link" option leading to a proper way
of detecting the link state based on HW interrogation and not on
software heuristic.

Note that DTS files for V3M Starter Kit, Draak and Eagle boards
contain the same property, the files are untouched due to unavailable
schematics to verify if the fix applies to these boards as well.

* tag 'renesas-fixes-for-v4.15' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
  arm64: dts: renesas: ulcb: Remove renesas, no-ether-link property
  arm64: dts: renesas: salvator-x: Remove renesas, no-ether-link property

Display WA #1183 was recently added to workaround
"Failures when enabling DPLL0 with eDP link rate 2.16
or 4.32 GHz and CD clock frequency 308.57 or 617.14 MHz
(CDCLK_CTL CD Frequency Select 10b or 11b) used in this
 enabling or in previous enabling."

This workaround was designed to minimize the impact only
to save the bad case with that link rates. But HW engineers
indicated that it should be safe to apply broadly, although
they were expecting the DPLL0 link rate to be unchanged on
runtime.

We need to cover 2 cases: when we are in fact enabling DPLL0
and when we are just changing the frequency with small
differences.

This is based on previous patch by Rodrigo Vivi with suggestions
from Ville Syrjälä.

Cc: Arthur J Runyan <arthur.j.runyan@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171204232210.4958-1-lucas.demarchi@intel.com
(cherry picked from commit 53421c2f)
[ Lucas: Backport to 4.15 adding back variable that has been removed on
  commits not meant to be backported ]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180102201837.6812-1-lucas.demarchi@intel.com

Pull x86 page table isolation fixes from Thomas Gleixner:
 "A couple of urgent fixes for PTI:

   - Fix a PTE mismatch between user and kernel visible mapping of the
     cpu entry area (differs vs. the GLB bit) and causes a TLB mismatch
     MCE on older AMD K8 machines

   - Fix the misplaced CR3 switch in the SYSCALL compat entry code which
     causes access to unmapped kernel memory resulting in double faults.

   - Fix the section mismatch of the cpu_tss_rw percpu storage caused by
     using a different mechanism for declaration and definition.

   - Two fixes for dumpstack which help to decode entry stack issues
     better

   - Enable PTI by default in Kconfig. We should have done that earlier,
     but it slipped through the cracks.

   - Exclude AMD from the PTI enforcement. Not necessarily a fix, but if
     AMD is so confident that they are not affected, then we should not
     burden users with the overhead"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/process: Define cpu_tss_rw in same section as declaration
  x86/pti: Switch to kernel CR3 at early in entry_SYSCALL_compat()
  x86/dumpstack: Print registers for first stack frame
  x86/dumpstack: Fix partial register dumps
  x86/pti: Make sure the user/kernel PTEs match
  x86/cpu, x86/pti: Do not enable PTI on AMD processors
  x86/pti: Enable PTI by default