Within show_valid_zones() the function test_pages_in_a_zone() should be
called for online memory blocks only.

Otherwise it might lead to the VM_BUG_ON due to uninitialized struct
pages (when CONFIG_DEBUG_VM_PGFLAGS kernel option is set):

 page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p))
 ------------[ cut here ]------------
 Call Trace:
 ([<000000000038f91e>] test_pages_in_a_zone+0xe6/0x168)
  [<0000000000923472>] show_valid_zones+0x5a/0x1a8
  [<0000000000900284>] dev_attr_show+0x3c/0x78
  [<000000000046f6f0>] sysfs_kf_seq_show+0xd0/0x150
  [<00000000003ef662>] seq_read+0x212/0x4b8
  [<00000000003bf202>] __vfs_read+0x3a/0x178
  [<00000000003bf3ca>] vfs_read+0x8a/0x148
  [<00000000003bfa3a>] ksys_read+0x62/0xb8
  [<0000000000bc2220>] system_call+0xdc/0x2d8

That VM_BUG_ON was triggered by the page poisoning introduced in
mm/sparse.c with the git commit d0dc12e8 ("mm/memory_hotplug:
optimize memory hotplug").

With the same commit the new 'nid' field has been added to the struct
memory_block in order to store and later on derive the node id for
offline pages (instead of accessing struct page which might be
uninitialized).  But one reference to nid in show_valid_zones() function
has been overlooked.  Fixed with current commit.  Also, nr_pages will
not be used any more after test_pages_in_a_zone() call, do not update
it.

Link: http://lkml.kernel.org/r/20180828090539.41491-1-zaslonko@linux.ibm.com
Fixes: d0dc12e8 ("mm/memory_hotplug: optimize memory hotplug")
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: <stable@vger.kernel.org>	[4.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Using a static const struct definition as part of a series of
declarations produces a false positive "Missing a blank line after
declarations" for code like:

  WARNING: Missing a blank line after declarations
  #710: FILE: drivers/gpu/drm/tidss/tidss_scale_coefs.c:137:
  +       int inc;
  +       static const struct {

So fix it.

Link: http://lkml.kernel.org/r/5905126e70b0ed1781e49265fd5c49c5090d0223.camel@perches.comSigned-off-by: Joe Perches <joe@perches.com>
Reported-by: Jyri Sarha <jsarha@ti.com>
Cc: "Valkeinen, Tomi" <tomi.valkeinen@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When getting rid of the general ipc_lock(), this was missed furthermore,
making the comment around the ipc object validity check bogus.  Under
EIDRM conditions, callers will in turn not see the error and continue
with the operation.

Link: http://lkml.kernel.org/r/20180824030920.GD3677@linux-r8p5
Link: http://lkml.kernel.org/r/20180823024051.GC13343@shao2-debian
Fixes: 82061c57 ("ipc: drop ipc_lock()")
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reported-by: kernel test robot <rong.a.chen@intel.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When scanning for movable pages, filter out Hugetlb pages if hugepage
migration is not supported.  Without this we hit infinte loop in
__offline_pages() where we do

	pfn = scan_movable_pages(start_pfn, end_pfn);
	if (pfn) { /* We have movable pages */
		ret = do_migrate_range(pfn, end_pfn);
		goto repeat;
	}

Fix this by checking hugepage_migration_supported both in
has_unmovable_pages which is the primary backoff mechanism for page
offlining and for consistency reasons also into scan_movable_pages
because it doesn't make any sense to return a pfn to non-migrateable
huge page.

This issue was revealed by, but not caused by 72b39cfc ("mm,
memory_hotplug: do not fail offlining too early").

Link: http://lkml.kernel.org/r/20180824063314.21981-1-aneesh.kumar@linux.ibm.com
Fixes: 72b39cfc ("mm, memory_hotplug: do not fail offlining too early")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reported-by: Haren Myneni <haren@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.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>

Scooped from an email from Matthew.

Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

debugfs_known_mountpoints[] is not used any more, so let's remove it.

Link: http://lkml.kernel.org/r/1535102651-19418-1-git-send-email-n-horiguchi@ah.jp.nec.comSigned-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently we get the following compiler warning:

    slabinfo.c:854:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
       if (s->object_size < min_objsize)
                          ^

due to the mismatch of signed/unsigned comparison.  ->object_size and
->slab_size are never expected to be negative, so let's define them as
unsigned int.

[n-horiguchi@ah.jp.nec.com: convert everything - none of these can be negative]
  Link: http://lkml.kernel.org/r/20180826234947.GA9787@hori1.linux.bs1.fc.nec.co.jp
Link: http://lkml.kernel.org/r/1535103134-20239-1-git-send-email-n-horiguchi@ah.jp.nec.comSigned-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If kmemleak built in to the kernel, but is disabled by default, the
debugfs file is never registered.  Because of this, it is not possible
to find out if the kernel is built with kmemleak support by checking for
the presence of this file.  To allow this, always register the file.

After this patch, if the file doesn't exist, kmemleak is not available
in the kernel.  If writing "scan" or any other value than "clear" to
this file results in EBUSY, then kmemleak is available but is disabled
by default and can be activated via the kernel command line.

Catalin: "that's also consistent with a late disabling of kmemleak when
the debugfs entry sticks around."

Link: http://lkml.kernel.org/r/20180824131220.19176-1-vincent.whitchurch@axis.comSigned-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit d70f2a14 ("include/linux/sched/mm.h: uninline mmdrop_async(),
etc") ignored the return value of arch_dup_mmap(). As a result, on x86,
a failure to duplicate the LDT (e.g. due to memory allocation error)
would leave the duplicated memory mapping in an inconsistent state.

Fix by using the return value, as it was before the change.

Link: http://lkml.kernel.org/r/20180823051229.211856-1-namit@vmware.com
Fixes: d70f2a14 ("include/linux/sched/mm.h: uninline mmdrop_async(), etc")
Signed-off-by: Nadav Amit <namit@vmware.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>

Commit 93065ac7 ("mm, oom: distinguish blockable mode for mmu
notifiers") has added an ability to skip over vmas with blockable mmu
notifiers. This however didn't call tlb_finish_mmu as it should.

As a result inc_tlb_flush_pending has been called without its pairing
dec_tlb_flush_pending and all callers mm_tlb_flush_pending would flush
even though this is not really needed.  This alone is not harmful and it
seems there shouldn't be any such callers for oom victims at all but
there is no real reason to skip tlb_finish_mmu on early skip either so
call it.

[mhocko@suse.com: new changelog]
Link: http://lkml.kernel.org/r/b752d1d5-81ad-7a35-2394-7870641be51c@i-love.sakura.ne.jpSigned-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When the memcg OOM killer runs out of killable tasks, it currently
prints a WARN with no further OOM context.  This has caused some user
confusion.

Warnings indicate a kernel problem.  In a reported case, however, the
situation was triggered by a nonsensical memcg configuration (hard limit
set to 0).  But without any VM context this wasn't obvious from the
report, and it took some back and forth on the mailing list to identify
what is actually a trivial issue.

Handle this OOM condition like we handle it in the global OOM killer:
dump the full OOM context and tell the user we ran out of tasks.

This way the user can identify misconfigurations easily by themselves
and rectify the problem - without having to go through the hassle of
running into an obscure but unsettling warning, finding the appropriate
kernel mailing list and waiting for a kernel developer to remote-analyze
that the memcg configuration caused this.

If users cannot make sense of why the OOM killer was triggered or why it
failed, they will still report it to the mailing list, we know that from
experience.  So in case there is an actual kernel bug causing this,
kernel developers will very likely hear about it.

Link: http://lkml.kernel.org/r/20180821160406.22578-1-hannes@cmpxchg.orgSigned-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull dma-mapping fixes from Christoph Hellwig:
 "A few fixes for the fallout of being a little more pedantic about dma
  masks"

* tag 'dma-mapping-4.19-2' of git://git.infradead.org/users/hch/dma-mapping:
  of/platform: initialise AMBA default DMA masks
  sparc: set a default 32-bit dma mask for OF devices
  kernel/dma/direct: take DMA offset into account in dma_direct_supported

Pull devicetree updates from Rob Herring:
 "A couple of new helper functions in preparation for some tree wide
  clean-ups.

  I'm sending these new helpers now for rc2 in order to simplify the
  dependencies on subsequent cleanups across the tree in 4.20"

* tag 'devicetree-fixes-for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  of: Add device_type access helper functions
  of: add node name compare helper functions
  of: add helper to lookup compatible child node

Pull ARM SoC fixes from Olof Johansson:
 "First batch of fixes post-merge window:

   - A handful of devicetree changes for i.MX2{3,8} to change over to
     new panel bindings. The platforms were moved from legacy
     framebuffers to DRM and some development board panels hadn't yet
     been converted.

   - OMAP fixes related to ti-sysc driver conversion fallout, fixing
     some register offsets, no_console_suspend fixes, etc.

   - Droid4 changes to fix flaky eMMC probing and vibrator DTS mismerge.

   - Fixed 0755->0644 permissions on a newly added file.

   - Defconfig changes to make ARM Versatile more useful with QEMU
     (helps testing).

   - Enable defconfig options for new TI SoC platform that was merged
     this window (AM6)"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  arm64: defconfig: Enable TI's AM6 SoC platform
  ARM: defconfig: Update the ARM Versatile defconfig
  ARM: dts: omap4-droid4: Fix emmc errors seen on some devices
  ARM: dts: Fix file permission for am335x-osd3358-sm-red.dts
  ARM: imx_v6_v7_defconfig: Select CONFIG_DRM_PANEL_SEIKO_43WVF1G
  ARM: mxs_defconfig: Select CONFIG_DRM_PANEL_SEIKO_43WVF1G
  ARM: dts: imx23-evk: Convert to the new display bindings
  ARM: dts: imx23-evk: Move regulators outside simple-bus
  ARM: dts: imx28-evk: Convert to the new display bindings
  ARM: dts: imx28-evk: Move regulators outside simple-bus
  Revert "ARM: dts: imx7d: Invert legacy PCI irq mapping"
  arm: dts: am4372: setup rtc as system-power-controller
  ARM: dts: omap4-droid4: fix vibrations on Droid 4
  bus: ti-sysc: Fix no_console_suspend handling
  bus: ti-sysc: Fix module register ioremap for larger offsets
  ARM: OMAP2+: Fix module address for modules using mpu_rt_idx
  ARM: OMAP2+: Fix null hwmod for ti-sysc debug

Pull x86 fixes from Thomas Gleixner:
 "Speculation:

   - Make the microcode check more robust

   - Make the L1TF memory limit depend on the internal cache physical
     address space and not on the CPUID advertised physical address
     space, which might be significantly smaller. This avoids disabling
     L1TF on machines which utilize the full physical address space.

   - Fix the GDT mapping for EFI calls on 32bit PTI

   - Fix the MCE nospec implementation to prevent #GP

  Fixes and robustness:

   - Use the proper operand order for LSL in the VDSO

   - Prevent NMI uaccess race against CR3 switching

   - Add a lockdep check to verify that text_mutex is held in
     text_poke() functions

   - Repair the fallout of giving native_restore_fl() a prototype

   - Prevent kernel memory dumps based on usermode RIP

   - Wipe KASAN shadow stack before rewinding the stack to prevent false
     positives

   - Move the AMS GOTO enforcement to the actual build stage to allow
     user API header extraction without a compiler

   - Fix a section mismatch introduced by the on demand VDSO mapping
     change

  Miscellaneous:

   - Trivial typo, GCC quirk removal and CC_SET/OUT() cleanups"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/pti: Fix section mismatch warning/error
  x86/vdso: Fix lsl operand order
  x86/mce: Fix set_mce_nospec() to avoid #GP fault
  x86/efi: Load fixmap GDT in efi_call_phys_epilog()
  x86/nmi: Fix NMI uaccess race against CR3 switching
  x86: Allow generating user-space headers without a compiler
  x86/dumpstack: Don't dump kernel memory based on usermode RIP
  x86/asm: Use CC_SET()/CC_OUT() in __gen_sigismember()
  x86/alternatives: Lockdep-enforce text_mutex in text_poke*()
  x86/entry/64: Wipe KASAN stack shadow before rewind_stack_do_exit()
  x86/irqflags: Mark native_restore_fl extern inline
  x86/build: Remove jump label quirk for GCC older than 4.5.2
  x86/Kconfig: Fix trivial typo
  x86/speculation/l1tf: Increase l1tf memory limit for Nehalem+
  x86/spectre: Add missing family 6 check to microcode check

Pull CPU hotplug fix from Thomas Gleixner:
 "Remove the stale skip_onerr member from the hotplug states"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Remove skip_onerr field from cpuhp_step structure

Pull core fixes from Thomas Gleixner:
 "A small set of updates for core code:

   - Prevent tracing in functions which are called from trace patching
     via stop_machine() to prevent executing half patched function trace
     entries.

   - Remove old GCC workarounds

   - Remove pointless includes of notifier.h"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Remove workaround for unreachable warnings from old GCC
  notifier: Remove notifier header file wherever not used
  watchdog: Mark watchdog touch functions as notrace

Fix the section mismatch warning in arch/x86/mm/pti.c:

WARNING: vmlinux.o(.text+0x6972a): Section mismatch in reference from the function pti_clone_pgtable() to the function .init.text:pti_user_pagetable_walk_pte()
The function pti_clone_pgtable() references
the function __init pti_user_pagetable_walk_pte().
This is often because pti_clone_pgtable lacks a __init
annotation or the annotation of pti_user_pagetable_walk_pte is wrong.
FATAL: modpost: Section mismatches detected.

Fixes: 85900ea5 ("x86/pti: Map the vsyscall page if needed")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/43a6d6a3-d69d-5eda-da09-0b1c88215a2a@infradead.org

This addresses a v4.19-rc1 regression in the PL111 DRM driver in
drivers/gpu/pl111/*

The driver uses the CMA KMS helpers and will thus at some point call
down to dma_alloc_attrs() to allocate a chunk of contigous DMA memory
for the framebuffer.

It appears that in v4.18, it was OK that this (and other DMA mastering
AMBA devices) left dev->coherent_dma_mask blank (zero).

In v4.19-rc1 the WARN_ON_ONCE(dev && !dev->coherent_dma_mask) in
dma_alloc_attrs() in include/linux/dma-mapping.h is triggered.  The
allocation later fails when get_coherent_dma_mask() is called from
__dma_alloc() and __dma_alloc() returns NULL:

drm-clcd-pl111 dev:20: coherent DMA mask is unset
drm-clcd-pl111 dev:20: [drm:drm_fb_helper_fbdev_setup] *ERROR*
 	       	        Failed to set fbdev configuration

It turns out that in commit 4d8bde88 ("OF: Don't set default
coherent DMA mask") the OF core stops setting the default DMA mask on
new devices, especially those lines of the patch:

- if (!dev->coherent_dma_mask)
-               dev->coherent_dma_mask = DMA_BIT_MASK(32);

Robin Murphy solved a similar problem in a5516219 ("of/platform:
Initialise default DMA masks") by simply assigning dev.coherent_dma_mask
and the dev.dma_mask to point to the same when creating devices from the
device tree, and introducing the same code into the code path creating
AMBA/PrimeCell devices solved my problem, graphics now come up.

The code simply assumes that the device can access all of the system
memory by setting the coherent DMA mask to 0xffffffff when creating a
device from the device tree, which is crude, but seems to be what kernel
v4.18 assumed.

The AMBA PrimeCells do not differ between coherent and streaming DMA so
we can just assign the same to any DMA mask.

Possibly drivers should augment their coherent DMA mask in accordance
with "dma-ranges" from the device tree if more finegranular masking is
needed.
Reported-by: Russell King <linux@armlinux.org.uk>
Fixes: 4d8bde88 ("OF: Don't set default coherent DMA mask")
Cc: Russell King <linux@armlinux.org.uk>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

This keeps the historic default behavior for devices without a DMA mask,
but removes the warning about a lacking DMA mask for doing DMA without
a mask.
Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>

Merge tag 'omap-for-v4.19/fixes-v2-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

Fixes for omap variants against v4.19-rc1

These are mostly fixes related to using ti-sysc interconnect target module
driver for accessing right register offsets for sgx and cpsw and for
no_console_suspend regression.

There is also a droid4 emmc fix where emmc may not get detected for some
models, and vibrator dts mismerge fix.

And we have a file permission fix for am335x-osd3358-sm-red.dts that
just got added. And we must tag RTC as system-power-controller for
am437x for PMIC to shut down during poweroff.

* tag 'omap-for-v4.19/fixes-v2-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: dts: omap4-droid4: Fix emmc errors seen on some devices
  ARM: dts: Fix file permission for am335x-osd3358-sm-red.dts
  arm: dts: am4372: setup rtc as system-power-controller
  ARM: dts: omap4-droid4: fix vibrations on Droid 4
  bus: ti-sysc: Fix no_console_suspend handling
  bus: ti-sysc: Fix module register ioremap for larger offsets
  ARM: OMAP2+: Fix module address for modules using mpu_rt_idx
  ARM: OMAP2+: Fix null hwmod for ti-sysc debug
Signed-off-by: Olof Johansson <olof@lixom.net>

In the __getcpu function, lsl is using the wrong target and destination
registers. Luckily, the compiler tends to choose %eax for both variables,
so it has been working so far.

Fixes: a582c540 ("x86/vdso: Use RDPID in preference to LSL when available")
Signed-off-by: Samuel Neves <sneves@dei.uc.pt>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180901201452.27828-1-sneves@dei.uc.pt

Pull watchdog fixlet from Wim Van Sebroeck:
 "Document support for r8a774a1"

* tag 'linux-watchdog-4.19-rc2' of git://www.linux-watchdog.org/linux-watchdog:
  dt-bindings: watchdog: renesas-wdt: Document r8a774a1 support

Pull clk fixes from Stephen Boyd:
 "Two small fixes, one for the x86 Stoney SoC to get a more accurate clk
  frequency and the other to fix a bad allocation in the Nuvoton NPCM7XX
  driver"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: x86: Set default parent to 48Mhz
  clk: npcm7xx: fix memory allocation

When a device has a DMA offset the dma capable result will change due
to the difference between the physical and DMA address.  Take that into
account.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>

The trick with flipping bit 63 to avoid loading the address of the 1:1
mapping of the poisoned page while the 1:1 map is updated used to work when
unmapping the page. But it falls down horribly when attempting to directly
set the page as uncacheable.

The problem is that when the cache mode is changed to uncachable, the pages
needs to be flushed from the cache first. But the decoy address is
non-canonical due to bit 63 flipped, and the CLFLUSH instruction throws a
#GP fault.

Add code to change_page_attr_set_clr() to fix the address before calling
flush.

Fixes: 284ce401 ("x86/memory_failure: Introduce {set, clear}_mce_nospec()")
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Link: https://lkml.kernel.org/r/20180831165506.GA9605@agluck-desk

Pull arm64 fixes from Will Deacon:
 "A few arm64 fixes came in this week, specifically fixing some nasty
  truncation of return values from firmware calls and resolving a
  VM_BUG_ON due to accessing uninitialised struct pages corresponding to
  NOMAP pages.

  Summary:

   - Fix typos in SVE documentation

   - Fix type-checking and implicit truncation for SMCCC calls

   - Force CONFIG_HOLES_IN_ZONE=y so that SLAB doesn't fall over NOMAP
     regions"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: mm: always enable CONFIG_HOLES_IN_ZONE
  arm/arm64: smccc-1.1: Handle function result as parameters
  arm/arm64: smccc-1.1: Make return values unsigned long
  Documentation/arm64/sve: Couple of improvements and typos

When PTI is enabled on x86-32 the kernel uses the GDT mapped in the fixmap
for the simple reason that this address is also mapped for user-space.

The efi_call_phys_prolog()/efi_call_phys_epilog() wrappers change the GDT
to call EFI runtime services and switch back to the kernel GDT when they
return. But the switch-back uses the writable GDT, not the fixmap GDT.

When that happened and and the CPU returns to user-space it switches to the
user %cr3 and tries to restore user segment registers. This fails because
the writable GDT is not mapped in the user page-table, and without a GDT
the fault handlers also can't be launched. The result is a triple fault and
reboot of the machine.

Fix that by restoring the GDT back to the fixmap GDT which is also mapped
in the user page-table.

Fixes: 7757d607 x86/pti: ('Allow CONFIG_PAGE_TABLE_ISOLATION for x86_32')
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: hpa@zytor.com
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/1535702738-10971-1-git-send-email-joro@8bytes.org

Pull xen fixes from Juergen Gross:

 - minor cleanup avoiding a warning when building with new gcc

 - a patch to add a new sysfs node for Xen frontend/backend drivers to
   make it easier to obtain the state of a pv device

 - two fixes for 32-bit pv-guests to avoid intermediate L1TF vulnerable
   PTEs

* tag 'for-linus-4.19b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: remove redundant variable save_pud
  xen: export device state to sysfs
  x86/pae: use 64 bit atomic xchg function in native_ptep_get_and_clear
  x86/xen: don't write ptes directly in 32-bit PV guests

Pull m68k fix from Geert Uytterhoeven:
 "Just a single fix for a bug introduced during the merge window: fix
  wrong date and time on PMU-based Macs"

* tag 'm68k-for-v4.19-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  m68k/mac: Use correct PMU response format

Pull i2c fixes from Wolfram Sang:

 - regression fixes for i801 and designware

 - better API and leak fix for releasing DMA safe buffers

 - better greppable strings for the bitbang algorithm

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: sh_mobile: fix leak when using DMA bounce buffer
  i2c: sh_mobile: define start_ch() void as it only returns 0 anyhow
  i2c: refactor function to release a DMA safe buffer
  i2c: algos: bit: make the error messages grepable
  i2c: designware: Re-init controllers with pm_disabled set on resume
  i2c: i801: Allow ACPI AML access I/O ports not reserved for SMBus

A NMI can hit in the middle of context switching or in the middle of
switch_mm_irqs_off().  In either case, CR3 might not match current->mm,
which could cause copy_from_user_nmi() and friends to read the wrong
memory.

Fix it by adding a new nmi_uaccess_okay() helper and checking it in
copy_from_user_nmi() and in __copy_from_user_nmi()'s callers.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rik van Riel <riel@surriel.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jann Horn <jannh@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/dd956eba16646fd0b15c3c0741269dfd84452dac.1535557289.git.luto@kernel.org

When bootstrapping an architecture, it's usual to generate the kernel's
user-space headers (make headers_install) before building a compiler.  Move
the compiler check (for asm goto support) to the archprepare target so that
it is only done when building code for the target.

Fixes: e501ce95 ("x86: Force asm-goto")
Reported-by: Helmut Grohne <helmutg@debian.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180829194317.GA4765@decadent.org.uk

show_opcodes() is used both for dumping kernel instructions and for dumping
user instructions. If userspace causes #PF by jumping to a kernel address,
show_opcodes() can be reached with regs->ip controlled by the user,
pointing to kernel code. Make sure that userspace can't trick us into
dumping kernel memory into dmesg.

Fixes: 7cccf072 ("x86/dumpstack: Add a show_ip() function")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: security@kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180828154901.112726-1-jannh@google.com

In preparation to remove direct access to device_node.type, add
of_node_is_type() and of_node_get_device_type() helpers to check and
retrieve the device type.

Cc: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>

When notifiers were there, `skip_onerr` was used to avoid calling
particular step startup/teardown callbacks in the CPU up/down rollback
path, which made the hotplug asymmetric.

As notifiers are gone now after the full state machine conversion, the
`skip_onerr` field is no longer required.

Remove it from the structure and its usage.
Signed-off-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1535439294-31426-1-git-send-email-mojha@codeaurora.org

Commit 6d526ee2 ("arm64: mm: enable CONFIG_HOLES_IN_ZONE for NUMA")
only enabled HOLES_IN_ZONE for NUMA systems because the NUMA code was
choking on the missing zone for nomap pages. This problem doesn't just
apply to NUMA systems.

If the architecture doesn't set HAVE_ARCH_PFN_VALID, pfn_valid() will
return true if the pfn is part of a valid sparsemem section.

When working with multiple pages, the mm code uses pfn_valid_within()
to test each page it uses within the sparsemem section is valid. On
most systems memory comes in MAX_ORDER_NR_PAGES chunks which all
have valid/initialised struct pages. In this case pfn_valid_within()
is optimised out.

Systems where this isn't true (e.g. due to nomap) should set
HOLES_IN_ZONE and provide HAVE_ARCH_PFN_VALID so that mm tests each
page as it works with it.

Currently non-NUMA arm64 systems can't enable HOLES_IN_ZONE, leading to
a VM_BUG_ON():

| page:fffffdff802e1780 is uninitialized and poisoned
| raw: ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff
| raw: ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff
| page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p))
| ------------[ cut here ]------------
| kernel BUG at include/linux/mm.h:978!
| Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[...]
| CPU: 1 PID: 25236 Comm: dd Not tainted 4.18.0 #7
| Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
| pstate: 40000085 (nZcv daIf -PAN -UAO)
| pc : move_freepages_block+0x144/0x248
| lr : move_freepages_block+0x144/0x248
| sp : fffffe0071177680
[...]
| Process dd (pid: 25236, stack limit = 0x0000000094cc07fb)
| Call trace:
|  move_freepages_block+0x144/0x248
|  steal_suitable_fallback+0x100/0x16c
|  get_page_from_freelist+0x440/0xb20
|  __alloc_pages_nodemask+0xe8/0x838
|  new_slab+0xd4/0x418
|  ___slab_alloc.constprop.27+0x380/0x4a8
|  __slab_alloc.isra.21.constprop.26+0x24/0x34
|  kmem_cache_alloc+0xa8/0x180
|  alloc_buffer_head+0x1c/0x90
|  alloc_page_buffers+0x68/0xb0
|  create_empty_buffers+0x20/0x1ec
|  create_page_buffers+0xb0/0xf0
|  __block_write_begin_int+0xc4/0x564
|  __block_write_begin+0x10/0x18
|  block_write_begin+0x48/0xd0
|  blkdev_write_begin+0x28/0x30
|  generic_perform_write+0x98/0x16c
|  __generic_file_write_iter+0x138/0x168
|  blkdev_write_iter+0x80/0xf0
|  __vfs_write+0xe4/0x10c
|  vfs_write+0xb4/0x168
|  ksys_write+0x44/0x88
|  sys_write+0xc/0x14
|  el0_svc_naked+0x30/0x34
| Code: aa1303e0 90001a01 91296421 94008902 (d4210000)
| ---[ end trace 1601ba47f6e883fe ]---

Remove the NUMA dependency.

Link: https://www.spinics.net/lists/arm-kernel/msg671851.html
Cc: <stable@vger.kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com>
Tested-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Now that the 68k Mac port has adopted the via-pmu driver, it must decode
the PMU response accordingly otherwise the date and time will be wrong.

Fixes: ebd72227 ("macintosh/via-pmu: Replace via-pmu68k driver with via-pmu driver")
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

Pull drm fixes from Dave Airlie:
 "Regular fixes pull:

   - Mediatek has a bunch of fixes to their RDMA and Overlay engines.

   - i915 has some Cannonlake/Geminilake watermark workarounds, LSPCON
     fix, HDCP free fix, audio fix and a ppgtt reference counting fix.

   - amdgpu has some SRIOV, Kasan, memory leaks and other misc fixes"

* tag 'drm-fixes-2018-08-31' of git://anongit.freedesktop.org/drm/drm: (35 commits)
  drm/i915/audio: Hook up component bindings even if displays are disabled
  drm/i915: Increase LSPCON timeout
  drm/i915: Stop holding a ref to the ppgtt from each vma
  drm/i915: Free write_buf that we allocated with kzalloc.
  drm/i915: Fix glk/cnl display w/a #1175
  drm/amdgpu: Need to set moved to true when evict bo
  drm/amdgpu: Remove duplicated power source update
  drm/amd/display: Fix memory leak caused by missed dc_sink_release
  drm/amdgpu: fix holding mn_lock while allocating memory
  drm/amdgpu: Power on uvd block when hw_fini
  drm/amdgpu: Update power state at the end of smu hw_init.
  drm/amdgpu: Fix vce initialize failed on Kaveri/Mullins
  drm/amdgpu: Enable/disable gfx PG feature in rlc safe mode
  drm/amdgpu: Adjust the VM size based on system memory size v2
  drm/mediatek: fix connection from RDMA2 to DSI1
  drm/mediatek: update some variable name from ovl to comp
  drm/mediatek: use layer_nr function to get layer number to init plane
  drm/mediatek: add function to return RDMA layer number
  drm/mediatek: add function to return OVL layer number
  drm/mediatek: add function to get layer number for component
  ...