linux-stable.git/arch, branch v4.9.99

s390/facilites: use stfle_fac_list array size for MAX_FACILITY_BIT

2018-05-09T07:50:24+00:00

commit 6f5165e864d240d15675cc2fb5a369d57e1f60d0 upstream.

Use the actual size of the facility list array within the lowcore
structure for the MAX_FACILITY_BIT define instead of a comment which
states what this is good for. This makes it a bit harder to break
things.

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

arm/arm64: KVM: Add PSCI version selection API

2018-05-09T07:50:19+00:00

commit 85bd0ba1ff9875798fad94218b627ea9f768f3c3 upstream.

Although we've implemented PSCI 0.1, 0.2 and 1.0, we expose either 0.1
or 1.0 to a guest, defaulting to the latest version of the PSCI
implementation that is compatible with the requested version. This is
no different from doing a firmware upgrade on KVM.

But in order to give a chance to hypothetical badly implemented guests
that would have a fit by discovering something other than PSCI 0.2,
let's provide a new API that allows userspace to pick one particular
version of the API.

This is implemented as a new class of "firmware" registers, where
we expose the PSCI version. This allows the PSCI version to be
save/restored as part of a guest migration, and also set to
any supported version if the guest requires it.

Cc: stable@vger.kernel.org #4.16
Reviewed-by: Christoffer Dall 
Signed-off-by: Marc Zyngier 
Signed-off-by: Greg Kroah-Hartman

powerpc/eeh: Fix race with driver un/bind

2018-05-01T22:13:10+00:00

commit f0295e047fcf52ccb42561fb7de6942f5201b676 upstream.

The current EEH callbacks can race with a driver unbind. This can
result in a backtraces like this:

  EEH: Frozen PHB#0-PE#1fc detected
  EEH: PE location: S000009, PHB location: N/A
  CPU: 2 PID: 2312 Comm: kworker/u258:3 Not tainted 4.15.6-openpower1 #2
  Workqueue: nvme-wq nvme_reset_work [nvme]
  Call Trace:
    dump_stack+0x9c/0xd0 (unreliable)
    eeh_dev_check_failure+0x420/0x470
    eeh_check_failure+0xa0/0xa4
    nvme_reset_work+0x138/0x1414 [nvme]
    process_one_work+0x1ec/0x328
    worker_thread+0x2e4/0x3a8
    kthread+0x14c/0x154
    ret_from_kernel_thread+0x5c/0xc8
  nvme nvme1: Removing after probe failure status: -19
  
  cpu 0x23: Vector: 300 (Data Access) at [c000000ff50f3800]
      pc: c0080000089a0eb0: nvme_error_detected+0x4c/0x90 [nvme]
      lr: c000000000026564: eeh_report_error+0xe0/0x110
      sp: c000000ff50f3a80
     msr: 9000000000009033
     dar: 400
   dsisr: 40000000
    current = 0xc000000ff507c000
    paca    = 0xc00000000fdc9d80   softe: 0        irq_happened: 0x01
      pid   = 782, comm = eehd
  Linux version 4.15.6-openpower1 (smc@smc-desktop) (gcc version 6.4.0 (Buildroot 2017.11.2-00008-g4b6188e)) #2 SM                                             P Tue Feb 27 12:33:27 PST 2018
  enter ? for help
    eeh_report_error+0xe0/0x110
    eeh_pe_dev_traverse+0xc0/0xdc
    eeh_handle_normal_event+0x184/0x4c4
    eeh_handle_event+0x30/0x288
    eeh_event_handler+0x124/0x170
    kthread+0x14c/0x154
    ret_from_kernel_thread+0x5c/0xc8

The first part is an EEH (on boot), the second half is the resulting
crash. nvme probe starts the nvme_reset_work() worker thread. This
worker thread starts touching the device which see a device error
(EEH) and hence queues up an event in the powerpc EEH worker
thread. nvme_reset_work() then continues and runs
nvme_remove_dead_ctrl_work() which results in unbinding the driver
from the device and hence releases all resources. At the same time,
the EEH worker thread starts doing the EEH .error_detected() driver
callback, which no longer works since the resources have been freed.

This fixes the problem in the same way the generic PCIe AER code (in
drivers/pci/pcie/aer/aerdrv_core.c) does. It makes the EEH code hold
the device_lock() while performing the driver EEH callbacks and
associated code. This ensures either the callbacks are no longer
register, or if they are registered the driver will not be removed
from underneath us.

This has been broken forever. The EEH call backs were first introduced
in 2005 (in 77bd7415610) but it's not clear if a lock was needed back
then.

Fixes: 77bd74156101 ("[PATCH] powerpc: PCI Error Recovery: PPC64 core recovery routines")
Cc: stable@vger.kernel.org # v2.6.16+
Signed-off-by: Michael Neuling 
Reviewed-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

x86/microcode/intel: Save microcode patch unconditionally

2018-05-01T22:13:09+00:00

commit 84749d83758af6576552046b215b9b7f37f9556b upstream.

save_mc_for_early() was a no-op on !CONFIG_HOTPLUG_CPU but the
generic_load_microcode() path saves the microcode patches it has found into
the cache of patches which is used for late loading too. Regardless of
whether CPU hotplug is used or not.

Make the saving unconditional so that late loading can find the proper
patch.

Reported-by: Vitezslav Samel 
Signed-off-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner 
Tested-by: Vitezslav Samel 
Tested-by: Ashok Raj 
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180418081140.GA2439@pc11.op.pod.cz
Link: https://lkml.kernel.org/r/20180421081930.15741-1-bp@alien8.de
Signed-off-by: Greg Kroah-Hartman

x86/smpboot: Don't use mwait_play_dead() on AMD systems

2018-05-01T22:13:09+00:00

commit da6fa7ef67f07108a1b0cb9fd9e7fcaabd39c051 upstream.

Recent AMD systems support using MWAIT for C1 state. However, MWAIT will
not allow deeper cstates than C1 on current systems.

play_dead() expects to use the deepest state available.  The deepest state
available on AMD systems is reached through SystemIO or HALT. If MWAIT is
available, it is preferred over the other methods, so the CPU never reaches
the deepest possible state.

Don't try to use MWAIT to play_dead() on AMD systems. Instead, use CPUIDLE
to enter the deepest state advertised by firmware. If CPUIDLE is not
available then fallback to HALT.

Signed-off-by: Yazen Ghannam 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Borislav Petkov 
Cc: stable@vger.kernel.org
Cc: Yazen Ghannam 
Link: https://lkml.kernel.org/r/20180403140228.58540-1-Yazen.Ghannam@amd.com
Signed-off-by: Greg Kroah-Hartman

x86/ipc: Fix x32 version of shmid64_ds and msqid64_ds

2018-05-01T22:13:09+00:00

commit 1a512c0882bd311c5b5561840fcfbe4c25b8f319 upstream.

A bugfix broke the x32 shmid64_ds and msqid64_ds data structure layout
(as seen from user space)  a few years ago: Originally, __BITS_PER_LONG
was defined as 64 on x32, so we did not have padding after the 64-bit
__kernel_time_t fields, After __BITS_PER_LONG got changed to 32,
applications would observe extra padding.

In other parts of the uapi headers we seem to have a mix of those
expecting either 32 or 64 on x32 applications, so we can't easily revert
the path that broke these two structures.

Instead, this patch decouples x32 from the other architectures and moves
it back into arch specific headers, partially reverting the even older
commit 73a2d096fdf2 ("x86: remove all now-duplicate header files").

It's not clear whether this ever made any difference, since at least
glibc carries its own (correct) copy of both of these header files,
so possibly no application has ever observed the definitions here.

Based on a suggestion from H.J. Lu, I tried out the tool from
https://github.com/hjl-tools/linux-header to find other such
bugs, which pointed out the same bug in statfs(), which also has
a separate (correct) copy in glibc.

Fixes: f4b4aae18288 ("x86/headers/uapi: Fix __BITS_PER_LONG value for x32 builds")
Signed-off-by: Arnd Bergmann 
Signed-off-by: Thomas Gleixner 
Cc: "H . J . Lu" 
Cc: Jeffrey Walton 
Cc: stable@vger.kernel.org
Cc: "H. Peter Anvin" 
Link: https://lkml.kernel.org/r/20180424212013.3967461-1-arnd@arndb.de
Signed-off-by: Greg Kroah-Hartman

rtc: opal: Fix OPAL RTC driver OPAL_BUSY loops

2018-05-01T22:13:09+00:00

commit 682e6b4da5cbe8e9a53f979a58c2a9d7dc997175 upstream.

The OPAL RTC driver does not sleep in case it gets OPAL_BUSY or
OPAL_BUSY_EVENT from firmware, which causes large scheduling
latencies, up to 50 seconds have been observed here when RTC stops
responding (BMC reboot can do it).

Fix this by converting it to the standard form OPAL_BUSY loop that
sleeps.

Fixes: 628daa8d5abf ("powerpc/powernv: Add RTC and NVRAM support plus RTAS fallbacks")
Cc: stable@vger.kernel.org # v3.2+
Signed-off-by: Nicholas Piggin 
Acked-by: Alexandre Belloni 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

s390/uprobes: implement arch_uretprobe_is_alive()

2018-04-29T09:32:03+00:00

commit 783c3b53b9506db3e05daacfe34e0287eebb09d8 upstream.

Implement s390 specific arch_uretprobe_is_alive() to avoid SIGSEGVs
observed with uretprobes in combination with setjmp/longjmp.

See commit 2dea1d9c38e4 ("powerpc/uprobes: Implement
arch_uretprobe_is_alive()") for more details.

With this implemented all test cases referenced in the above commit
pass.

Reported-by: Ziqian SUN 
Cc:  # v4.3+
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390: correct module section names for expoline code revert

2018-04-29T09:32:00+00:00

[ Upstream commit 6cf09958f32b9667bb3ebadf74367c791112771b ]

The main linker script vmlinux.lds.S for the kernel image merges
the expoline code patch tables into two section ".nospec_call_table"
and ".nospec_return_table". This is *not* done for the modules,
there the sections retain their original names as generated by gcc:
".s390_indirect_call", ".s390_return_mem" and ".s390_return_reg".

The module_finalize code has to check for the compiler generated
section names, otherwise no code patching is done. This slows down
the module code in case of "spectre_v2=off".

Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5ed6 ("s390: introduce execute-trampolines for branches")
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390: correct nospec auto detection init order

2018-04-29T09:32:00+00:00

[ Upstream commit 6a3d1e81a434fc311f224b8be77258bafc18ccc6 ]

With CONFIG_EXPOLINE_AUTO=y the call of spectre_v2_auto_early() via
early_initcall is done *after* the early_param functions. This
overwrites any settings done with the nobp/no_spectre_v2/spectre_v2
parameters. The code patching for the kernel is done after the
evaluation of the early parameters but before the early_initcall
is done. The end result is a kernel image that is patched correctly
but the kernel modules are not.

Make sure that the nospec auto detection function is called before the
early parameters are evaluated and before the code patching is done.

Fixes: 6e179d64126b ("s390: add automatic detection of the spectre defense")
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman