Pull percpu fixes from Tejun Heo:
"Late percpu pull request for v4.16-rc6.

- percpu allocator pool replenishing no longer triggers OOM or
warning messages.

Also, the alloc interface now understands __GFP_NORETRY and
__GFP_NOWARN. This is to allow avoiding OOMs from userland
triggered actions like bpf map creation.

Also added cond_resched() in alloc loop.

- perpcu allocation now can be interrupted by kill sigs to avoid
deadlocking OOM killer.

- Added Dennis Zhou as a co-maintainer.

He has rewritten the area map allocator, understands most of the
code base and has been responsive for all bug reports"

* 'for-4.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu_ref: Update doc to dissuade users from depending on internal RCU grace periods
mm: Allow to kill tasks doing pcpu_alloc() and waiting for pcpu_balance_workfn()
percpu: include linux/sched.h for cond_resched()
percpu: add a schedule point in pcpu_balance_workfn()
percpu: allow select gfp to be passed to underlying allocators
percpu: add __GFP_NORETRY semantics to the percpu balancing path
percpu: match chunk allocator declarations with definitions
percpu: add Dennis Zhou as a percpu co-maintainer

Pull libata fixes from Tejun Heo:
"I sat on them too long and it's quite a few this late, but nothing has
a wide blast area. The changes are...

- Fix corner cases in SG command handling.

- Recent introduction of default powersaving mode config option
exposed several devices with broken powersaving behaviors. A number
of patches to update the blacklist accordingly.

- Fix a kernel panic on SAS hotplug.

- Other misc and device specific updates"

* 'for-4.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
libata: Modify quirks for MX100 to limit NCQ_TRIM quirk to MU01 version
libata: Make Crucial BX100 500GB LPM quirk apply to all firmware versions
libata: Apply NOLPM quirk to Crucial M500 480 and 960GB SSDs
libata: Enable queued TRIM for Samsung SSD 860
PCI: Add function 1 DMA alias quirk for Highpoint RocketRAID 644L
ahci: Add PCI-id for the Highpoint Rocketraid 644L card
ata: do not schedule hot plug if it is a sas host
libata: disable LPM for Crucial BX100 SSD 500GB drive
libata: Apply NOLPM quirk to Crucial MX100 512GB SSDs
libata: update documentation for sysfs interfaces
ata: sata_rcar: Remove unused variable in sata_rcar_init_controller()
libata: transport: cleanup documentation of sysfs interface
sata_rcar: Reset SATA PHY when Salvator-X board resumes
libata: don't try to pass through NCQ commands to non-NCQ devices
libata: remove WARN() for DMA or PIO command without data
libata: fix length validation of ATAPI-relayed SCSI commands
ata: libahci: fix comment indentation
ahci: Add check for device presence (PCIe hot unplug) in ahci_stop_engine()
libata: Fix compile warning with ATA_DEBUG enabled

percpu_ref internally uses sched-RCU to implement the percpu -> atomic
mode switching and the documentation suggested that this could be
depended upon. This doesn't seem like a good idea.

* percpu_ref uses sched-RCU which has different grace periods regular
RCU. Users may combine percpu_ref with regular RCU usage and
incorrectly believe that regular RCU grace periods are performed by
percpu_ref. This can lead to, for example, use-after-free due to
premature freeing.

* percpu_ref has a grace period when switching from percpu to atomic
mode. It doesn't have one between the last put and release. This
distinction is subtle and can lead to surprising bugs.

* percpu_ref allows starting in and switching to atomic mode manually
for debugging and other purposes. This means that there may not be
any grace periods from kill to release.

This patch makes it clear that the grace periods are percpu_ref's
internal implementation detail and can't be depended upon by the
users.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

When commit 9c7be59fc519af ("libata: Apply NOLPM quirk to Crucial MX100
512GB SSDs") was added it inherited the ATA_HORKAGE_NO_NCQ_TRIM quirk
from the existing "Crucial_CT*MX100*" entry, but that entry sets model_rev
to "MU01", where as the entry adding the NOLPM quirk sets it to NULL.

This means that after this commit we no apply the NO_NCQ_TRIM quirk to
all "Crucial_CT512MX100*" SSDs even if they have the fixed "MU02"
firmware. This commit splits the "Crucial_CT512MX100*" quirk into 2
quirks, one for the "MU01" firmware and one for all other firmware
versions, so that we once again only apply the NO_NCQ_TRIM quirk to the
"MU01" firmware version.

Fixes: 9c7be59fc519af ("libata: Apply NOLPM quirk to ... MX100 512GB SSDs")
Cc: stable@vger.kernel.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

In case of memory deficit and low percpu memory pages,
pcpu_balance_workfn() takes pcpu_alloc_mutex for a long
time (as it makes memory allocations itself and waits
for memory reclaim). If tasks doing pcpu_alloc() are
choosen by OOM killer, they can't exit, because they
are waiting for the mutex.

The patch makes pcpu_alloc() to care about killing signal
and use mutex_lock_killable(), when it's allowed by GFP
flags. This guarantees, a task does not miss SIGKILL
from OOM killer.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Pull x86/pti updates from Thomas Gleixner:
"Another set of melted spectrum updates:

- Iron out the last late microcode loading issues by actually
checking whether new microcode is present and preventing the CPU
synchronization to run into a timeout induced hang.

- Remove Skylake C2 from the microcode blacklist according to the
latest Intel documentation

- Fix the VM86 POPF emulation which traps if VIP is set, but VIF is
not. Enhance the selftests to catch that kind of issue

- Annotate indirect calls/jumps for objtool on 32bit. This is not a
functional issue, but for consistency sake its the right thing to
do.

- Fix a jump label build warning observed on SPARC64 which uses 32bit
storage for the code location which is casted to 64 bit pointer w/o
extending it to 64bit first.

- Add two new cpufeature bits. Not really an urgent issue, but
provides them for both x86 and x86/kvm work. No impact on the
current kernel"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/microcode: Fix CPU synchronization routine
x86/microcode: Attempt late loading only when new microcode is present
x86/speculation: Remove Skylake C2 from Speculation Control microcode blacklist
jump_label: Fix sparc64 warning
x86/speculation, objtool: Annotate indirect calls/jumps for objtool on 32-bit kernels
x86/vm86/32: Fix POPF emulation
selftests/x86/entry_from_vm86: Add test cases for POPF
selftests/x86/entry_from_vm86: Exit with 1 if we fail
x86/cpufeatures: Add Intel PCONFIG cpufeature
x86/cpufeatures: Add Intel Total Memory Encryption cpufeature

Commit b17e5729a630 ("libata: disable LPM for Crucial BX100 SSD 500GB
drive"), introduced a ATA_HORKAGE_NOLPM quirk for Crucial BX100 500GB SSDs
but limited this to the MU02 firmware version, according to:
http://www.crucial.com/usa/en/support-ssd-firmware

MU02 is the last version, so there are no newer possibly fixed versions
and if the MU02 version has broken LPM then the MU01 almost certainly
also has broken LPM, so this commit changes the quirk to apply to all
firmware versions.

Fixes: b17e5729a630 ("libata: disable LPM for Crucial BX100 SSD 500GB...")
Cc: stable@vger.kernel.org
Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

microblaze build broke due to missing declaration of the
cond_resched() invocation added recently. Let's include linux/sched.h
explicitly.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: kbuild test robot <fengguang.wu@intel.com>

Pull x86 fix from Thomas Gleixner:
"A single fix for vmalloc_fault() which uses p*d_huge() unconditionally
whether CONFIG_HUGETLBFS is set or not. In case of CONFIG_HUGETLBFS=n
this results in a crash as p*d_huge() returns 0 in that case"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix vmalloc_fault to use pXd_large

Emanuel reported an issue with a hang during microcode update because my
dumb idea to use one atomic synchronization variable for both rendezvous
- before and after update - was simply bollocks:

microcode: microcode_reload_late: late_cpus: 4
microcode: __reload_late: cpu 2 entered
microcode: __reload_late: cpu 1 entered
microcode: __reload_late: cpu 3 entered
microcode: __reload_late: cpu 0 entered
microcode: __reload_late: cpu 1 left
microcode: Timeout while waiting for CPUs rendezvous, remaining: 1

CPU1 above would finish, leave and the others will still spin waiting for
it to join.

So do two synchronization atomics instead, which makes the code a lot more
straightforward.

Also, since the update is serialized and it also takes quite some time per
microcode engine, increase the exit timeout by the number of CPUs on the
system.

That's ok because the moment all CPUs are done, that timeout will be cut
short.

Furthermore, panic when some of the CPUs timeout when returning from a
microcode update: we can't allow a system with not all cores updated.

Also, as an optimization, do not do the exit sync if microcode wasn't
updated.

Reported-by: Emanuel Czirai <xftroxgpx@protonmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Emanuel Czirai <xftroxgpx@protonmail.com>
Tested-by: Ashok Raj <ashok.raj@intel.com>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lkml.kernel.org/r/20180314183615.17629-2-bp@alien8.de

There have been reports of the Crucial M500 480GB model not working
with LPM set to min_power / med_power_with_dipm level.

It has not been tested with medium_power, but that typically has no
measurable power-savings.

Note the reporters Crucial_CT480M500SSD3 has a firmware version of MU03
and there is a MU05 update available, but that update does not mention any
LPM fixes in its changelog, so the quirk matches all firmware versions.

In my experience the LPM problems with (older) Crucial SSDs seem to be
limited to higher capacity versions of the SSDs (different firmware?),
so this commit adds a NOLPM quirk for the 480 and 960GB versions of the
M500, to avoid LPM causing issues with these SSDs.

Cc: stable@vger.kernel.org
Reported-and-tested-by: Martin Steigerwald <martin@lichtvoll.de>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

When a large BPF percpu map is destroyed, I have seen
pcpu_balance_workfn() holding cpu for hundreds of milliseconds.

On KASAN config and 112 hyperthreads, average time to destroy a chunk
is ~4 ms.

[ 2489.841376] destroy chunk 1 in 4148689 ns
...
[ 2490.093428] destroy chunk 32 in 4072718 ns

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>