Pull powerpc fix from Michael Ellerman:
 "One fix for an oops when using SRIOV, introduced by the recent changes
  to support compound IOMMU groups.

  Thanks to Alexey Kardashevskiy"

* tag 'powerpc-5.0-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/powernv/sriov: Register IOMMU groups for VFs

Pull SCSI fixes from James Bottomley:
 "Four small fixes: three in drivers and one in the core.

  The core fix is also minor in scope since the bug it fixes is only
  known to affect systems using SCSI reservations. Of the driver bugs,
  the libsas one is the most major because it can lead to multiple disks
  on the same expander not being exposed"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: core: reset host byte in DID_NEXUS_FAILURE case
  scsi: libsas: Fix rphy phy_identifier for PHYs with end devices attached
  scsi: sd_zbc: Fix sd_zbc_report_zones() buffer allocation
  scsi: libiscsi: Fix race between iscsi_xmit_task and iscsi_complete_task

Merge branch 'fixes-v5.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Pull keys fixes from James Morris:
 "Two fixes from Eric Biggers"

* 'fixes-v5.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  KEYS: always initialize keyring_index_key::desc_len
  KEYS: user: Align the payload buffer

Pull power management fixes from Rafael Wysocki:
 "These fix a regression in the PM-runtime framework introduced by the
  recent switch-over of it to using hrtimers and a use-after-free
  introduced by one of the recent changes in the scmi-cpufreq driver.

  Specifics:

   - Use hrtimer_try_to_cancel() instead of hrtimer_cancel() in the
     PM-runtime framework to avoid a possible timer-related deadlock
     introduced recently (Vincent Guittot).

   - Reorder the scmi-cpufreq driver code to avoid accessing memory that
     has just been freed (Yangtao Li)"

* tag 'pm-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM-runtime: Fix deadlock when canceling hrtimer
  cpufreq: scmi: Fix use-after-free in scmi_cpufreq_exit()

Pull ARM SoC fixes from Arnd Bergmann:
 "Only a handful of device tree fixes, all simple enough:

  NVIDIA Tegra:
   - Fix a regression for booting on chromebooks

  TI OMAP:
   - Two fixes PHY mode on am335x reference boards

  Marvell mvebu:
   - A regression fix for Armada XP NAND flash controllers
   - An incorrect reset signal on the clearfog board"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  ARM: tegra: Restore DT ABI on Tegra124 Chromebooks
  ARM: dts: am335x-evm: Fix PHY mode for ethernet
  ARM: dts: am335x-evmsk: Fix PHY mode for ethernet
  arm64: dts: clearfog-gt-8k: fix SGMII PHY reset signal
  ARM: dts: armada-xp: fix Armada XP boards NAND description

Pull ARC fixes from Vineet Gupta:
 "Fixes for ARC for 5.0, bunch of those are stable fodder anyways so
  sooner the better.

   - Fix memcpy to prevent prefetchw beyond end of buffer [Eugeniy]

   - Enable unaligned access early to prevent exceptions given newer gcc
     code gen [Eugeniy]

   - Tighten up uboot arg checking to prevent false negatives and also
     allow both jtag and bootloading to coexist w/o config option as
     needed by kernelCi folks [Eugeniy]

   - Set slab alignment to 8 for ARC to avoid the atomic64_t unalign
     [Alexey]

   - Disable regfile auto save on interrupts on HSDK platform due to a
     silicon issue [Vineet]

   - Avoid HS38x boot printing crash by not reading HS48x only reg
     [Vineet]"

* tag 'arc-5.0-final' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARCv2: don't assume core 0x54 has dual issue
  ARC: define ARCH_SLAB_MINALIGN = 8
  ARC: enable uboot support unconditionally
  ARC: U-boot: check arguments paranoidly
  ARCv2: support manual regfile save on interrupts
  ARC: uacces: remove lp_start, lp_end from clobber list
  ARC: fix actionpoints configuration detection
  ARCv2: lib: memcpy: fix doing prefetchw outside of buffer
  ARCv2: Enable unaligned access in early ASM code

Pull parisc fixes from Helge Deller:
 "Fix ptrace syscall number modification which has been broken since
  kernel v4.5 and provide alternative email addresses for the remaining
  users of the retired parisc-linux.org email domain"

* 'parisc-5.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  CREDITS/MAINTAINERS: Retire parisc-linux.org email domain
  parisc: Fix ptrace syscall number modification

Merge tag 'kbuild-fixes-v5.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild fixes from Masahiro Yamada:

 - fix scripts/kallsyms.c to correctly check too long symbol names

 - fix sh build error for the combination of CONFIG_OF_EARLY_FLATTREE=y
   and CONFIG_USE_BUILTIN_DTB=n

* tag 'kbuild-fixes-v5.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  sh: fix build error for invisible CONFIG_BUILTIN_DTB_SOURCE
  kallsyms: Handle too long symbols in kallsyms.c

Pull drm fixes from Dave Airlie:
 "This contains a single i915 tiled display fix, and a set of
  amdgpu/radeon fixes.

  i915:

   - tiled display fix

  amdgpu/radeon:

   - runtime PM fix

   - bulk moves disable (fix is too large for 5.0)

   - a set of display fixes that are all cc'ed stable so we didn't want
     to leave them until -next"

* tag 'drm-fixes-2019-02-22' of git://anongit.freedesktop.org/drm/drm:
  drm/amdgpu: disable bulk moves for now
  drm/amd/display: set clocks to 0 on suspend on dce80
  drm/amd/display: fix optimize_bandwidth func pointer for dce80
  drm/amd/display: Fix negative cursor pos programming
  drm/i915/fbdev: Actually configure untiled displays
  drm/amd/display: Raise dispclk value for dce11
  drm/amd/display: Fix MST reboot/poweroff sequence
  drm/amdgpu: Update sdma golden setting for vega20
  drm/amdgpu: Set DPM_FLAG_NEVER_SKIP when enabling PM-runtime
  gpu: drm: radeon: Set DPM_FLAG_NEVER_SKIP when enabling PM-runtime

Pull rdma fixes from Jason Gunthorpe:
 "Small set of three regression fixing patches, things are looking
  pretty good here.

   - Fix cxgb4 to work again with non-4k page sizes

   - NULL pointer oops in SRP during sg_reset"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  iw_cxgb4: cq/qp mask depends on bar2 pages in a host page
  cxgb4: Export sge_host_page_size to ulds
  RDMA/srp: Rework SCSI device reset handling

syzbot hit the 'BUG_ON(index_key->desc_len == 0);' in __key_link_begin()
called from construct_alloc_key() during sys_request_key(), because the
length of the key description was never calculated.

The problem is that we rely on ->desc_len being initialized by
search_process_keyrings(), specifically by search_nested_keyrings().
But, if the process isn't subscribed to any keyrings that never happens.

Fix it by always initializing keyring_index_key::desc_len as soon as the
description is set, like we already do in some places.

The following program reproduces the BUG_ON() when it's run as root and
no session keyring has been installed.  If it doesn't work, try removing
pam_keyinit.so from /etc/pam.d/login and rebooting.

    #include <stdlib.h>
    #include <unistd.h>
    #include <keyutils.h>

    int main(void)
    {
            int id = add_key("keyring", "syz", NULL, 0, KEY_SPEC_USER_KEYRING);

            keyctl_setperm(id, KEY_OTH_WRITE);
            setreuid(5000, 5000);
            request_key("user", "desc", "", id);
    }

Reported-by: syzbot+ec24e95ea483de0a24da@syzkaller.appspotmail.com
Fixes: b2a4df20 ("KEYS: Expand the capacity of a keyring")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.morris@microsoft.com>

Align the payload of "user" and "logon" keys so that users of the
keyrings service can access it as a struct that requires more than
2-byte alignment.  fscrypt currently does this which results in the read
of fscrypt_key::size being misaligned as it needs 4-byte alignment.

Align to __alignof__(u64) rather than __alignof__(long) since in the
future it's conceivable that people would use structs beginning with
u64, which on some platforms would require more than 'long' alignment.
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Fixes: 2aa349f6 ("[PATCH] Keys: Export user-defined keyring operations")
Fixes: 88bd6ccd ("ext4 crypto: add encryption key management facilities")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.morris@microsoft.com>

Pull clk fixes from Stephen Boyd:
 "A few more fixes for clk drivers causing regressions this release.

  Two Allwinner index fixes for A31 and V3 and two Microchip AT91 fixes
  for an incorrect clk parent linkage and a miscalculated number of
  clks"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: at91: fix masterck name
  clk: at91: fix at91sam9x5 peripheral clock number
  clk: sunxi: A31: Fix wrong AHB gate number
  clk: sunxi-ng: v3s: Fix TCON reset de-assert bit

mvebu fixes for 5.0 (part 2)

Fix PHY reset signal on clearfog gt 8K (Armada 8040 based)
Fix NAND description on Armada XP boards which was broken since a few
release

* tag 'mvebu-fixes-5.0-2' of git://git.infradead.org/linux-mvebu:
  arm64: dts: clearfog-gt-8k: fix SGMII PHY reset signal
  ARM: dts: armada-xp: fix Armada XP boards NAND description
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Merge tag 'omap-for-v5.0/fixes-rc7-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into arm/fixes

Two am335x ethernet phy mode fixes for v5.0-rc cycle

Recent changes with commit cd28d1d6: ("net: phy: at803x: Disable phy
delay for RGMII mode") broke Ethernet on am335x-evmsk, and turns out some
device driver fixes are needed.

Even without the driver fixes, am335x needs to run in rgmii-id mode instead
rgmii-txid mode. Things have been working based on luck as the broken driver
has been configuring rgmii-id mode. Let's fix that as that way things work
as they're supposed to work from hardware wiring point of view.

* tag 'omap-for-v5.0/fixes-rc7-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: dts: am335x-evm: Fix PHY mode for ethernet
  ARM: dts: am335x-evmsk: Fix PHY mode for ethernet
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

* pm-cpufreq-fixes:
  cpufreq: scmi: Fix use-after-free in scmi_cpufreq_exit()

A bit bigger than normal for this week due to fixes for some long
standing display issues that are bound for stable.  These changes would
be going to stable anyway, so I figured it was better via 5.0 than 5.1.
- Several display fixes
- Fix PX systems due to core changes in runtime pm
- Disable bulk moves.  They are fixed in 5.1, but fix is too invasive for 5.0
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190220225715.3240-1-alexander.deucher@amd.com

The first release of core4 (0x54) was dual issue only (HS4x).
Newer releases allow hardware to be configured as single issue (HS3x)
or dual issue.

Prevent accessing a HS4x only aux register in HS3x, which otherwise
leads to illegal instruction exceptions
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

Retire the parisc-linux.org email domain and provide alternative email
addresses for the remaining users, as agreed upon with them.
Signed-off-by: Helge Deller <deller@gmx.de>

Commit 910cd32e ("parisc: Fix and enable seccomp filter support")
introduced a regression in ptrace-based syscall tampering: when tracer
changes syscall number to -1, the kernel fails to initialize %r28 with
-ENOSYS and subsequently fails to return the error code of the failed
syscall to userspace.

This erroneous behaviour could be observed with a simple strace syscall
fault injection command which is expected to print something like this:

$ strace -a0 -ewrite -einject=write:error=enospc echo hello
write(1, "hello\n", 6) = -1 ENOSPC (No space left on device) (INJECTED)
write(2, "echo: ", 6) = -1 ENOSPC (No space left on device) (INJECTED)
write(2, "write error", 11) = -1 ENOSPC (No space left on device) (INJECTED)
write(2, "\n", 1) = -1 ENOSPC (No space left on device) (INJECTED)
+++ exited with 1 +++

After commit 910cd32e it loops printing
something like this instead:

write(1, "hello\n", 6../strace: Failed to tamper with process 12345: unexpectedly got no error (return value 0, error 0)
) = 0 (INJECTED)

This bug was found by strace test suite.

Fixes: 910cd32e ("parisc: Fix and enable seccomp filter support")
Cc: stable@vger.kernel.org # v4.5+
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Tested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>

The default value of ARCH_SLAB_MINALIGN in "include/linux/slab.h" is
"__alignof__(unsigned long long)" which for ARC unexpectedly turns out
to be 4. This is not a compiler bug, but as defined by ARC ABI [1]

Thus slab allocator would allocate a struct which is 32-bit aligned,
which is generally OK even if struct has long long members.
There was however potetial problem when it had any atomic64_t which
use LLOCKD/SCONDD instructions which are required by ISA to take
64-bit addresses. This is the problem we ran into

[    4.015732] EXT4-fs (mmcblk0p2): re-mounted. Opts: (null)
[    4.167881] Misaligned Access
[    4.172356] Path: /bin/busybox.nosuid
[    4.176004] CPU: 2 PID: 171 Comm: rm Not tainted 4.19.14-yocto-standard #1
[    4.182851]
[    4.182851] [ECR   ]: 0x000d0000 => Check Programmer's Manual
[    4.190061] [EFA   ]: 0xbeaec3fc
[    4.190061] [BLINK ]: ext4_delete_entry+0x210/0x234
[    4.190061] [ERET  ]: ext4_delete_entry+0x13e/0x234
[    4.202985] [STAT32]: 0x80080002 : IE K
[    4.207236] BTA: 0x9009329c   SP: 0xbe5b1ec4  FP: 0x00000000
[    4.212790] LPS: 0x9074b118  LPE: 0x9074b120 LPC: 0x00000000
[    4.218348] r00: 0x00000040  r01: 0x00000021 r02: 0x00000001
...
...
[    4.270510] Stack Trace:
[    4.274510]   ext4_delete_entry+0x13e/0x234
[    4.278695]   ext4_rmdir+0xe0/0x238
[    4.282187]   vfs_rmdir+0x50/0xf0
[    4.285492]   do_rmdir+0x9e/0x154
[    4.288802]   EV_Trap+0x110/0x114

The fix is to make sure slab allocations are 64-bit aligned.

Do note that atomic64_t is __attribute__((aligned(8)) which means gcc
does generate 64-bit aligned references, relative to beginning of
container struct. However the issue is if the container itself is not
64-bit aligned, atomic64_t ends up unaligned which is what this patch
ensures.

[1] https://github.com/foss-for-synopsys-dwc-arc-processors/toolchain/wiki/files/ARCv2_ABI.pdfSigned-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: <stable@vger.kernel.org> # 4.8+
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: reworked changelog, added dependency on LL64+LLSC]

After reworking U-boot args handling code and adding paranoid
arguments check we can eliminate CONFIG_ARC_UBOOT_SUPPORT and
enable uboot support unconditionally.

For JTAG case we can assume that core registers will come up
reset value of 0 or in worst case we rely on user passing
'-on=clear_regs' to Metaware debugger.

Cc: stable@vger.kernel.org
Tested-by: Corentin LABBE <clabbe@baylibre.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

Handle U-boot arguments paranoidly:
 * don't allow to pass unknown tag.
 * try to use external device tree blob only if corresponding tag
   (TAG_DTB) is set.
 * don't check uboot_tag if kernel build with no ARC_UBOOT_SUPPORT.

NOTE:
If U-boot args are invalid we skip them and try to use embedded device
tree blob. We can't panic on invalid U-boot args as we really pass
invalid args due to bug in U-boot code.
This happens if we don't provide external DTB to U-boot and
don't set 'bootargs' U-boot environment variable (which is default
case at least for HSDK board) In that case we will pass
{r0 = 1 (bootargs in r2); r1 = 0; r2 = 0;} to linux which is invalid.

While I'm at it refactor U-boot arguments handling code.

Cc: stable@vger.kernel.org
Tested-by: Corentin LABBE <clabbe@baylibre.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

There's a hardware bug which affects the HSDK platform, triggered by
micro-ops for auto-saving regfile on taken interrupt. The workaround is
to inhibit autosave.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

Newer ARC gcc handles lp_start, lp_end in a different way and doesn't
like them in the clobber list.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

Fix reversed logic while actionpoints configuration (full/min)
detection.

Fixies: 7dd380c3 ("ARC: boot log: print Action point details")
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

ARCv2 optimized memcpy uses PREFETCHW instruction for prefetching the
next cache line but doesn't ensure that the line is not past the end of
the buffer. PRETECHW changes the line ownership and marks it dirty,
which can cause data corruption if this area is used for DMA IO.

Fix the issue by avoiding the PREFETCHW. This leads to performance
degradation but it is OK as we'll introduce new memcpy implementation
optimized for unaligned memory access using.

We also cut off all PREFETCH instructions at they are quite useless
here:
 * we call PREFETCH right before LOAD instruction call.
 * we copy 16 or 32 bytes of data (depending on CONFIG_ARC_HAS_LL64)
   in a main logical loop. so we call PREFETCH 4 times (or 2 times)
   for each L1 cache line (in case of 64B L1 cache Line which is
   default case). Obviously this is not optimal.
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

It is currently done in arc_init_IRQ() which might be too late
considering gcc 7.3.1 onwards (GNU 2018.03) generates unaligned
memory accesses by default

Cc: stable@vger.kernel.org #4.4+
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: rewrote changelog]

Pull ceph fixes from Ilya Dryomov:
 "Two bug fixes for old issues, both marked for stable"

* tag 'ceph-for-5.0-rc8' of git://github.com/ceph/ceph-client:
  ceph: avoid repeatedly adding inode to mdsc->snap_flush_list
  libceph: handle an empty authorize reply

Pull late arm64 fixes from Will Deacon:
 "Three small arm64 fixes for 5.0.

  They fix a build breakage with clang introduced in 4.20, an oversight
  in our sigframe restoration relating to the SSBS bit and a boot fix
  for systems with newer revisions of our interrupt controller.

  Summary:

   - Fix handling of PSTATE.SSBS bit in sigreturn()

   - Fix version checking of the GIC during early boot

   - Fix clang builds failing due to use of NEON in the crypto code"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: Relax GIC version check during early boot
  arm64/neon: Disable -Wincompatible-pointer-types when building with Clang
  arm64: fix SSBS sanitization

Merge misc fixes from Andrew Morton:
 "23 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (23 commits)
  mm, memory_hotplug: fix off-by-one in is_pageblock_removable
  mm: don't let userspace spam allocations warnings
  slub: fix a crash with SLUB_DEBUG + KASAN_SW_TAGS
  kasan, slab: remove redundant kasan_slab_alloc hooks
  kasan, slab: make freelist stored without tags
  kasan, slab: fix conflicts with CONFIG_HARDENED_USERCOPY
  kasan: prevent tracing of tags.c
  kasan: fix random seed generation for tag-based mode
  tmpfs: fix link accounting when a tmpfile is linked in
  psi: avoid divide-by-zero crash inside virtual machines
  mm: handle lru_add_drain_all for UP properly
  mm, page_alloc: fix a division by zero error when boosting watermarks v2
  mm/debug.c: fix __dump_page() for poisoned pages
  proc, oom: do not report alien mms when setting oom_score_adj
  slub: fix SLAB_CONSISTENCY_CHECKS + KASAN_SW_TAGS
  kasan, slub: fix more conflicts with CONFIG_SLAB_FREELIST_HARDENED
  kasan, slub: fix conflicts with CONFIG_SLAB_FREELIST_HARDENED
  kasan, slub: move kasan_poison_slab hook before page_address
  kmemleak: account for tagged pointers when calculating pointer range
  kasan, kmemleak: pass tagged pointers to kmemleak
  ...

Rong Chen has reported the following boot crash:

    PGD 0 P4D 0
    Oops: 0000 [#1] PREEMPT SMP PTI
    CPU: 1 PID: 239 Comm: udevd Not tainted 5.0.0-rc4-00149-gefad4e47 #1
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
    RIP: 0010:page_mapping+0x12/0x80
    Code: 5d c3 48 89 df e8 0e ad 02 00 85 c0 75 da 89 e8 5b 5d c3 0f 1f 44 00 00 53 48 89 fb 48 8b 43 08 48 8d 50 ff a8 01 48 0f 45 da <48> 8b 53 08 48 8d 42 ff 83 e2 01 48 0f 44 c3 48 83 38 ff 74 2f 48
    RSP: 0018:ffff88801fa87cd8 EFLAGS: 00010202
    RAX: ffffffffffffffff RBX: fffffffffffffffe RCX: 000000000000000a
    RDX: fffffffffffffffe RSI: ffffffff820b9a20 RDI: ffff88801e5c0000
    RBP: 6db6db6db6db6db7 R08: ffff88801e8bb000 R09: 0000000001b64d13
    R10: ffff88801fa87cf8 R11: 0000000000000001 R12: ffff88801e640000
    R13: ffffffff820b9a20 R14: ffff88801f145258 R15: 0000000000000001
    FS:  00007fb2079817c0(0000) GS:ffff88801dd00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000000000006 CR3: 000000001fa82000 CR4: 00000000000006a0
    Call Trace:
     __dump_page+0x14/0x2c0
     is_mem_section_removable+0x24c/0x2c0
     removable_show+0x87/0xa0
     dev_attr_show+0x25/0x60
     sysfs_kf_seq_show+0xba/0x110
     seq_read+0x196/0x3f0
     __vfs_read+0x34/0x180
     vfs_read+0xa0/0x150
     ksys_read+0x44/0xb0
     do_syscall_64+0x5e/0x4a0
     entry_SYSCALL_64_after_hwframe+0x49/0xbe

and bisected it down to commit efad4e47 ("mm, memory_hotplug:
is_mem_section_removable do not pass the end of a zone").

The reason for the crash is that the mapping is garbage for poisoned
(uninitialized) page.  This shouldn't happen as all pages in the zone's
boundary should be initialized.

Later debugging revealed that the actual problem is an off-by-one when
evaluating the end_page.  'start_pfn + nr_pages' resp 'zone_end_pfn'
refers to a pfn after the range and as such it might belong to a
differen memory section.

This along with CONFIG_SPARSEMEM then makes the loop condition
completely bogus because a pointer arithmetic doesn't work for pages
from two different sections in that memory model.

Fix the issue by reworking is_pageblock_removable to be pfn based and
only use struct page where necessary.  This makes the code slightly
easier to follow and we will remove the problematic pointer arithmetic
completely.

Link: http://lkml.kernel.org/r/20190218181544.14616-1-mhocko@kernel.org
Fixes: efad4e47 ("mm, memory_hotplug: is_mem_section_removable do not pass the end of a zone")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: <rong.a.chen@intel.com>
Tested-by: <rong.a.chen@intel.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

memdump_user usually gets fed unchecked userspace input.  Blasting a
full backtrace into dmesg every time is a bit excessive - I'm not sure
on the kernel rule in general, but at least in drm we're trying not to
let unpriviledge userspace spam the logs freely.  Definitely not entire
warning backtraces.

It also means more filtering for our CI, because our testsuite exercises
these corner cases and so hits these a lot.

Link: http://lkml.kernel.org/r/20190220204058.11676-1-daniel.vetter@ffwll.chSigned-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jan Stancek <jstancek@redhat.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In process_slab(), "p = get_freepointer()" could return a tagged
pointer, but "addr = page_address()" always return a native pointer.  As
the result, slab_index() is messed up here,

    return (p - addr) / s->size;

All other callers of slab_index() have the same situation where "addr"
is from page_address(), so just need to untag "p".

    # cat /sys/kernel/slab/hugetlbfs_inode_cache/alloc_calls

    Unable to handle kernel paging request at virtual address 2bff808aa4856d48
    Mem abort info:
      ESR = 0x96000007
      Exception class = DABT (current EL), IL = 32 bits
      SET = 0, FnV = 0
      EA = 0, S1PTW = 0
    Data abort info:
      ISV = 0, ISS = 0x00000007
      CM = 0, WnR = 0
    swapper pgtable: 64k pages, 48-bit VAs, pgdp = 0000000002498338
    [2bff808aa4856d48] pgd=00000097fcfd0003, pud=00000097fcfd0003, pmd=00000097fca30003, pte=00e8008b24850712
    Internal error: Oops: 96000007 [#1] SMP
    CPU: 3 PID: 79210 Comm: read_all Tainted: G             L    5.0.0-rc7+ #84
    Hardware name: HPE Apollo 70             /C01_APACHE_MB         , BIOS L50_5.13_1.0.6 07/10/2018
    pstate: 00400089 (nzcv daIf +PAN -UAO)
    pc : get_map+0x78/0xec
    lr : get_map+0xa0/0xec
    sp : aeff808989e3f8e0
    x29: aeff808989e3f940 x28: ffff800826200000
    x27: ffff100012d47000 x26: 9700000000002500
    x25: 0000000000000001 x24: 52ff8008200131f8
    x23: 52ff8008200130a0 x22: 52ff800820013098
    x21: ffff800826200000 x20: ffff100013172ba0
    x19: 2bff808a8971bc00 x18: ffff1000148f5538
    x17: 000000000000001b x16: 00000000000000ff
    x15: ffff1000148f5000 x14: 00000000000000d2
    x13: 0000000000000001 x12: 0000000000000000
    x11: 0000000020000002 x10: 2bff808aa4856d48
    x9 : 0000020000000000 x8 : 68ff80082620ebb0
    x7 : 0000000000000000 x6 : ffff1000105da1dc
    x5 : 0000000000000000 x4 : 0000000000000000
    x3 : 0000000000000010 x2 : 2bff808a8971bc00
    x1 : ffff7fe002098800 x0 : ffff80082620ceb0
    Process read_all (pid: 79210, stack limit = 0x00000000f65b9361)
    Call trace:
     get_map+0x78/0xec
     process_slab+0x7c/0x47c
     list_locations+0xb0/0x3c8
     alloc_calls_show+0x34/0x40
     slab_attr_show+0x34/0x48
     sysfs_kf_seq_show+0x2e4/0x570
     kernfs_seq_show+0x12c/0x1a0
     seq_read+0x48c/0xf84
     kernfs_fop_read+0xd4/0x448
     __vfs_read+0x94/0x5d4
     vfs_read+0xcc/0x194
     ksys_read+0x6c/0xe8
     __arm64_sys_read+0x68/0xb0
     el0_svc_handler+0x230/0x3bc
     el0_svc+0x8/0xc
    Code: d3467d2a 9ac92329 8b0a0e6a f9800151 (c85f7d4b)
    ---[ end trace a383a9a44ff13176 ]---
    Kernel panic - not syncing: Fatal exception
    SMP: stopping secondary CPUs
    SMP: failed to stop secondary CPUs 1-7,32,40,127
    Kernel Offset: disabled
    CPU features: 0x002,20000c18
    Memory Limit: none
    ---[ end Kernel panic - not syncing: Fatal exception ]---

Link: http://lkml.kernel.org/r/20190220020251.82039-1-cai@lca.pwSigned-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kasan_slab_alloc() calls in kmem_cache_alloc() and kmem_cache_alloc_node()
are redundant as they are already called via slab_alloc/slab_alloc_node()->
slab_post_alloc_hook()->kasan_slab_alloc().  Remove them.

Link: http://lkml.kernel.org/r/4ca1655cdcfc4379c49c50f7bf80f81c4ad01485.1550602886.git.andreyknvl@google.comSigned-off-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Qian Cai <cai@lca.pw>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgeniy Stepanov <eugenis@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Similarly to "kasan, slub: move kasan_poison_slab hook before
page_address", move kasan_poison_slab() before alloc_slabmgmt(), which
calls page_address(), to make page_address() return value to be
non-tagged.  This, combined with calling kasan_reset_tag() for off-slab
slab management object, leads to freelist being stored non-tagged.

Link: http://lkml.kernel.org/r/dfb53b44a4d00de3879a05a9f04c1f55e584f7a1.1550602886.git.andreyknvl@google.comSigned-off-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Qian Cai <cai@lca.pw>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgeniy Stepanov <eugenis@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Similarly to commit 96fedce2 ("kasan: make tag based mode work with
CONFIG_HARDENED_USERCOPY"), we need to reset pointer tags in
__check_heap_object() in mm/slab.c before doing any pointer math.

Link: http://lkml.kernel.org/r/9a5c0f958db10e69df5ff9f2b997866b56b7effc.1550602886.git.andreyknvl@google.comSigned-off-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Qian Cai <cai@lca.pw>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgeniy Stepanov <eugenis@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Similarly to commit 0d0c8de8 ("kasan: mark file common so ftrace
doesn't trace it") add the -pg flag to mm/kasan/tags.c to prevent
conflicts with tracing.

Link: http://lkml.kernel.org/r/9c4c3ce5ccfb894c7fe66d91de7c1da2787b4da4.1550602886.git.andreyknvl@google.comSigned-off-by: Andrey Konovalov <andreyknvl@google.com>
Reported-by: Qian Cai <cai@lca.pw>
Tested-by: Qian Cai <cai@lca.pw>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Evgeniy Stepanov <eugenis@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

There are two issues with assigning random percpu seeds right now:

1. We use for_each_possible_cpu() to iterate over cpus, but cpumask is
   not set up yet at the moment of kasan_init(), and thus we only set
   the seed for cpu #0.

2. A call to get_random_u32() always returns the same number and produces
   a message in dmesg, since the random subsystem is not yet initialized.

Fix 1 by calling kasan_init_tags() after cpumask is set up.

Fix 2 by using get_cycles() instead of get_random_u32(). This gives us
lower quality random numbers, but it's good enough, as KASAN is meant to
be used as a debugging tool and not a mitigation.

Link: http://lkml.kernel.org/r/1f815cc914b61f3516ed4cc9bfd9eeca9bd5d9de.1550677973.git.andreyknvl@google.comSigned-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.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>

tmpfs has a peculiarity of accounting hard links as if they were
separate inodes: so that when the number of inodes is limited, as it is
by default, a user cannot soak up an unlimited amount of unreclaimable
dcache memory just by repeatedly linking a file.

But when v3.11 added O_TMPFILE, and the ability to use linkat() on the
fd, we missed accommodating this new case in tmpfs: "df -i" shows that
an extra "inode" remains accounted after the file is unlinked and the fd
closed and the actual inode evicted.  If a user repeatedly links
tmpfiles into a tmpfs, the limit will be hit (ENOSPC) even after they
are deleted.

Just skip the extra reservation from shmem_link() in this case: there's
a sense in which this first link of a tmpfile is then cheaper than a
hard link of another file, but the accounting works out, and there's
still good limiting, so no need to do anything more complicated.

Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1902182134370.7035@eggly.anvils
Fixes: f4e0c30c ("allow the temp files created by open() to be linked to")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Matej Kupljen <matej.kupljen@gmail.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>