Commit graph

724472 commits

Author SHA1 Message Date
Serge Semin
c7aeb0afdc NTB: ntb_pp: Add full multi-port NTB API support
Current Ping Pong driver can't truly work with multi-port devices.
Additionally it requires the Scratchpad registers being available
on NTB device. This patches rewrites the driver so one would
perform the cyclic Ping-Pong algorithm around all the available
NTB peers and makes it working with NTB hardware, which doesn't
support Scratchpads, but such alternative as NTB Message register.
Additional cleanups are also added here.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:24 -05:00
Serge Semin
f1678a4c66 NTB: Fix UB/bug in ntb_mw_get_align()
Simple (1 << pidx) operation causes undefined behaviour when
pidx >= 32. It must be casted to u64 to match the actual return
value of ntb_link_is_up() method, so to have all the possible
peer indexes covered and to get rid of undefined behaviour.
Additionally there are special macros in "linux/bitops.h" to perform
the bit-set-shift operations, so it's recommended to have them used
for proper bit setting.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:24 -05:00
Serge Semin
417cf39cfe NTB: Set dma mask and dma coherent mask to NTB devices
The dma_mask and dma_coherent_mask fields of the NTB struct device
weren't initialized in hardware drivers. In fact it should be done
instead of PCIe interface usage, since NTB clients are supposed to
use NTB API and left unaware of real hardware implementation.
In addition to that ntb_device_register() method shouldn't clear
the passed ntb_dev structure, since it dma_mask is initialized
by hardware drivers.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Serge Semin
b87ab21935 NTB: Rename NTB messaging API methods
There is a common methods signature form used over all the NTB API
like functions naming scheme, arguments names and order, etc.
Recently added NTB messaging API IO callbacks were named a bit
different so should be renamed to be in compliance with the rest
of the API.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Arnd Bergmann
c6fad21a8d ntb_hw_switchtec: fix logic error
Newer gcc (version 7 and 8 presumably) warn about a statement mixing
the << operator with logical and:

drivers/ntb/hw/mscc/ntb_hw_switchtec.c: In function 'switchtec_ntb_init_sndev':
drivers/ntb/hw/mscc/ntb_hw_switchtec.c:888:24: error: '<<' in boolean context, did you mean '<' ? [-Werror=int-in-bool-context]

My interpretation here is that the author must have intended a bitmask
rather than a comparison, so I'm changing the '&&' to '&', which makes
a lot more sense in the context.

Fixes: 1b249475275d ("ntb_hw_switchtec: Allow using Switchtec NTB in multi-partition setups")
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe
1e2fd202f8 ntb_hw_switchtec: Check for alignment of the buffer in mw_set_trans()
With Switchtec hardware, the buffer used for a memory window must be
aligned to its size (the hardware only replaces the lower bits). In
certain circumstances dma_alloc_coherent() will not provide a buffer
that adheres to this requirement like when using the CMA and
CONFIG_CMA_ALIGNMENT is set lower than the buffer size.

When we get an unaligned buffer mw_set_trans() should return an error.
We also log an error so we know the cause of the problem.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe
cbd27448fa ntb_transport: Fix bug with max_mw_size parameter
When using the max_mw_size parameter of ntb_transport to limit the size of
the Memory windows, communication cannot be established and the queues
freeze.

This is because the mw_size that's reported to the peer is correctly
limited but the size used locally is not. So the MW is initialized
with a buffer smaller than the window but the TX side is using the
full window. This means the TX side will be writing to a region of the
window that points nowhere.

This is easily fixed by applying the same limit to tx_size in
ntb_transport_init_queue().

Fixes: e26a5843f7 ("NTB: Split ntb_hw_intel and ntb_transport drivers")
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Allen Hubbe
c3840c7c3b MAINTAINERS: NTB: Update contact info
I am no longer employed by Dell EMC.  For the purposes of NTB driver
development and maintenance, please contact me via my personal email.

Signed-off-by: Allen Hubbe <allenbh@gmail.com>
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe
d04be142b8 ntb_hw_switchtec: Force down the link before initializing
If one host crashes and soft reboots, the other host may not see a
link down event. Then when the crashed host comes back up, the
surviving host may not know the link was reset and the NTB clients
may not work without being reset.

To solve this, we send a LINK_FORCE_DOWN message to each peer every
time we come up, before we register the NTB device. If a surviving
host still thinks the link is up it will take it down immediately.
In this way, once the crashed host comes up fully, it will send a
regular link up event as per usual and the link will be properly
restarted.

While we are in the area, this also fixes the MSG_LINK_UP message that
was in the link down function that was reported by Doug Meyers.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reported-by: ThanhTuThai <cruisethai@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe
270d32e63c ntb_hw_switchtec: Crosslink doorbells and messages
In a crosslink configuration doorbells and messages largely work the
same but the NTB registers must be accessed through the reserved LUT
window. Also, as a bonus, seeing there are now two independent sets of
NTB links, both partitions can actually use all 60 doorbell registers
instead of them having to be split into two for each partition.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe
0175250182 ntb_hw_switchtec: Add initialization code for crosslink
Crosslink is a feature of the Switchtec switches that is similar to
the B2B mode of other NTB devices. It allows a system to be designed
that is perfectly symmetric with two identical switches that link
two hosts together.

In order for the system to be symmetric, there is an empty host-less
partition between the two switches which the host must enumerate and
assign BAR addresses to. The firmware in the switch manages this
specially so that the BAR addresses on both sides of the empty
partition will be identical despite being in the same partition with
the same address space.

The driver determines whether crosslink is enabled by a flag set in
the NTB partition info registers which are set by the switch's
configuration file.

When crosslink is enabled, a reserved LUT window is setup to point to
the peer's switch's NTB registers and the local MWs are set to forward
to the host-less partition's BARs. (Yes, this hurts my brain too.)
Once this is setup, largely the same NTB infrastructure is used to
communicate between the two hosts.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe
45f447deb2 ntb_hw_switchtec: Expand PFF CSR registers
The PFF CSR registers actual mirrors the PCI configuration space
for all the ports in the switch. Previously, this was not needed by
the driver but will be used by the crosslink code to enumerate the
bus in an host-less centre partition.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe
bbe35ca5aa ntb_hw_switchtec: Make switchtec_ntb_init_req_id_table() more general
This is a prep patch in order to support the crosslink feature which
will require the driver to setup the requester ID table in another
partition as well as it's own. To aid this, create a helper function
which sets up the requester IDs from an array.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe
12cb203b1b ntb_hw_switchtec: Create helper function to setup reserved LUT MWs
This is a prep patch in order to support the crosslink feature which
will require the driver to use another reserved LUT window. To
simplify this we move the code which sets up the reserved LUT window
into a helper function which will be used by the crosslink
initialization.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Logan Gunthorpe
c3585cd870 ntb_hw_switchtec: Keep track of the number of LUT windows used by the driver
This is a prep patch in order to support the crosslink feature which will
require the driver to use another reserved LUT window. To simplify this,
we add some code to track the number of reserved LUT windows in use
instead of assuming this is always 1.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Kelvin Cao
3df54c870f ntb_hw_switchtec: Allow using Switchtec NTB in multi-partition setups
Allow using Switchtec NTB in setups that have more than two partitions.
Note: this does not enable having multi-host communication, it only
allows for a single NTB link between two hosts in a network that might
have more than two.

Use following logic to determine the NT peer partition:

1) If there are 2 partitions, and the target vector is set in
   the Switchtec configuration, use the partition specified in target
   vector.
2) If there are 2 partitions and target vector is unset
   use the only other partition as specified in the NT EP map.
3) If there are more than 2 partitions and target vector is set
   use the other partition specified in target vector.
4) If there are more than 2 partitions and target vector is unset,
   this is invalid and report an error.

Signed-off-by: Kelvin Cao <kelvin.cao@microsemi.com>
[logang@deltatee.com: commit message fleshed out]
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Jon Mason
2dd0f6a64a NTB: switchtec_ntb: Add new line on appropriate printks
Trivial addition of "\n" to the dev_* prints where necessary

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Colin Ian King
c5ec8b451a NTB: switchtec_ntb: fix spelling mistake: "peforming" -> "performing"
Trivial fix to spelling mistake in dev_err error message

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-By: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Dave Jiang
3f7756728e ntb: remove Intel Atom NTB driver support
Removing dead code since this is not being used.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Greg Kroah-Hartman
0ed08f829b ntb: remove unneeded DRIVER_LICENSE #defines
There is no need to #define the license of the driver, just put it in
the MODULE_LICENSE() line directly as a text string.

This allows tools that check that the module license matches the source
code license to work properly, as there is no need to unwind the
unneeded dereference, especially when the string is defined just a few
lines above the usage of it.

Reported-and-reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Allen Hubbe <Allen.Hubbe@emc.com>
Cc: Gary R Hook <gary.hook@amd.com>
Cc: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:23 -05:00
Doug Meyer
140eb52277 NTB: ntb_hw_switchtec: Fix peer BAR bug in switchtec_ntb_init_shared_mw
This resolves a bug which may incorrectly configure the peer host's
LUT for shared memory window access. The code was using the local
host's first BAR number, rather than the peer hosts's first BAR
number, to determine what peer NT control register to program.

The bug will cause the Switchtec NTB link to work only if both peers
have the same first NTB BAR configured. In all other configurations,
the link will not come up, failing silently.

When both hosts have the same first BAR, the configuration works only
because the first BAR numbers happent to be the same. When the hosts
do not have the same first BAR, then the LUT translation will not be
configured in the correct peer LUT and will not give the peer the
shared memory window access required for the link to operate.

Signed-off-by: Doug Meyer <dmeyer@gigaio.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Fixes: 678784a44ae8 ("NTB: switchtec_ntb: Initialize hardware for memory windows")
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2018-01-28 22:17:22 -05:00
Linus Torvalds
d8a5b80568 Linux 4.15 2018-01-28 13:20:33 -08:00
Linus Torvalds
24b1cccf92 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 retpoline fixlet from Thomas Gleixner:
 "Remove the ESP/RSP thunks for retpoline as they cannot ever work.

  Get rid of them before they show up in a release"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/retpoline: Remove the esp/rsp thunk
2018-01-28 12:24:36 -08:00
Linus Torvalds
32c6cdf75c Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "A set of small fixes for 4.15:

   - Fix vmapped stack synchronization on systems with 4-level paging
     and a large amount of memory caused by a missing 5-level folding
     which made the pgd synchronization logic to fail and causing double
     faults.

   - Add a missing sanity check in the vmalloc_fault() logic on 5-level
     paging systems.

   - Bring back protection against accessing a freed initrd in the
     microcode loader which was lost by a wrong merge conflict
     resolution.

   - Extend the Broadwell micro code loading sanity check.

   - Add a missing ENDPROC annotation in ftrace assembly code which
     makes ORC unhappy.

   - Prevent loading the AMD power module on !AMD platforms. The load
     itself is uncritical, but an unload attempt results in a kernel
     crash.

   - Update Peter Anvins role in the MAINTAINERS file"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ftrace: Add one more ENDPROC annotation
  x86: Mark hpa as a "Designated Reviewer" for the time being
  x86/mm/64: Tighten up vmalloc_fault() sanity checks on 5-level kernels
  x86/mm/64: Fix vmapped stack syncing on very-large-memory 4-level systems
  x86/microcode: Fix again accessing initrd after having been freed
  x86/microcode/intel: Extend BDW late-loading further with LLC size check
  perf/x86/amd/power: Do not load AMD power module on !AMD platforms
2018-01-28 12:19:23 -08:00
Linus Torvalds
07b0137c02 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Thomas Gleixner:
 "A single fix for a ~10 years old problem which causes high resolution
  timers to stop after a CPU unplug/plug cycle due to a stale flag in
  the per CPU hrtimer base struct.

  Paul McKenney was hunting this for about a year, but the heisenbug
  nature made it resistant against debug attempts for quite some time"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Reset hrtimer cpu base proper on CPU hotplug
2018-01-28 12:17:35 -08:00
Linus Torvalds
624441927f Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Thomas Gleixner:
 "A single bug fix to prevent a subtle deadlock in the scheduler core
  code vs cpu hotplug"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Fix cpu.max vs. cpuhotplug deadlock
2018-01-28 11:51:45 -08:00
Linus Torvalds
39e383626c Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
 "Four patches which all address lock inversions and deadlocks in the
  perf core code and the Intel debug store"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86: Fix perf,x86,cpuhp deadlock
  perf/core: Fix ctx::mutex deadlock
  perf/core: Fix another perf,trace,cpuhp lock inversion
  perf/core: Fix lock inversion between perf,trace,cpuhp
2018-01-28 11:48:25 -08:00
Linus Torvalds
8c76e31a6a Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Thomas Gleixner:
 "Two final locking fixes for 4.15:

   - Repair the OWNER_DIED logic in the futex code which got wreckaged
     with the recent fix for a subtle race condition.

   - Prevent the hard lockup detector from triggering when dumping all
     held locks in the system"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/lockdep: Avoid triggering hardlockup from debug_show_all_locks()
  futex: Fix OWNER_DEAD fixup
2018-01-28 11:20:35 -08:00
Josh Poimboeuf
dd085168a7 x86/ftrace: Add one more ENDPROC annotation
When ORC support was added for the ftrace_64.S code, an ENDPROC
for function_hook() was missed. This results in the following warning:

  arch/x86/kernel/ftrace_64.o: warning: objtool: .entry.text+0x0: unreachable instruction

Fixes: e2ac83d74a ("x86/ftrace: Fix ORC unwinding from ftrace handlers")
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20180128022150.dqierscqmt3uwwsr@treble
2018-01-28 09:19:12 +01:00
Thomas Gleixner
d5421ea43d hrtimer: Reset hrtimer cpu base proper on CPU hotplug
The hrtimer interrupt code contains a hang detection and mitigation
mechanism, which prevents that a long delayed hrtimer interrupt causes a
continous retriggering of interrupts which prevent the system from making
progress. If a hang is detected then the timer hardware is programmed with
a certain delay into the future and a flag is set in the hrtimer cpu base
which prevents newly enqueued timers from reprogramming the timer hardware
prior to the chosen delay. The subsequent hrtimer interrupt after the delay
clears the flag and resumes normal operation.

If such a hang happens in the last hrtimer interrupt before a CPU is
unplugged then the hang_detected flag is set and stays that way when the
CPU is plugged in again. At that point the timer hardware is not armed and
it cannot be armed because the hang_detected flag is still active, so
nothing clears that flag. As a consequence the CPU does not receive hrtimer
interrupts and no timers expire on that CPU which results in RCU stalls and
other malfunctions.

Clear the flag along with some other less critical members of the hrtimer
cpu base to ensure starting from a clean state when a CPU is plugged in.

Thanks to Paul, Sebastian and Anna-Maria for their help to get down to the
root cause of that hard to reproduce heisenbug. Once understood it's
trivial and certainly justifies a brown paperbag.

Fixes: 41d2e49493 ("hrtimer: Tune hrtimer_interrupt hang logic")
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Sewior <bigeasy@linutronix.de>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801261447590.2067@nanos
2018-01-27 15:12:22 +01:00
H. Peter Anvin
8a95b74d50 x86: Mark hpa as a "Designated Reviewer" for the time being
Due to some unfortunate events, I have not been directly involved in
the x86 kernel patch flow for a while now.  I have also not been able
to ramp back up by now like I had hoped to, and after reviewing what I
will need to work on both internally at Intel and elsewhere in the near
term, it is clear that I am not going to be able to ramp back up until
late 2018 at the very earliest.

It is not acceptable to not recognize that this load is currently
taken by Ingo and Thomas without my direct participation, so I mark
myself as R: (designated reviewer) rather than M: (maintainer) until
further notice.  This is in fact recognizing the de facto situation
for the past few years.

I have obviously no intention of going away, and I will do everything
within my power to improve Linux on x86 and x86 for Linux.  This,
however, puts credit where it is due and reflects a change of focus.

This patch also removes stale entries for portions of the x86
architecture which have not been maintained separately from arch/x86
for a long time.  If there is a reason to re-introduce them then that
can happen later.

Signed-off-by: H. Peter Anvin <h.peter.anvin@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Bruce Schlobohm <bruce.schlobohm@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180125195934.5253-1-hpa@zytor.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-27 10:11:00 +01:00
Linus Torvalds
c4e0ca7fa2 RISC-V: We have a new mailing list and git repo!
Sorry to send something essentially as late as possible (Friday after an
 rc9), but we managed to get a mailing list for the RISC-V Linux port.
 We've been using patches@groups.riscv.org for a while, but that list has
 some problems (it's Google Groups and it's shared over all RISC-V
 software projects).  The new infaread.org list is much better.   We just
 got it on Wednesday but I used it a bit on Thursday to shake out all the
 configuration problems and it appears to be in working order.
 
 When I updated the mailing list I noticed that the MAINTAINERS file was
 pointing to our github repo, but now that we have a kernel.org repo I'd
 like to point to that instead so I changed that as well.  We'll be
 centralizing all RISC-V Linux related development here as that seems to
 be the saner way to go about it.
 
 I can understand if it's too late to get this into 4.15, but given that
 it's not a code change I was hoping it'd still be OK.  It would be nice
 to have the new mailing list and git repo in the release tarballs so
 when people start to find bugs they'll get to the right place.
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Merge tag 'riscv-for-linus-4.15-maintainers' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux

Pull RISC-V update from Palmer Dabbelt:
 "RISC-V: We have a new mailing list and git repo!

  Sorry to send something essentially as late as possible (Friday after
  an rc9), but we managed to get a mailing list for the RISC-V Linux
  port. We've been using patches@groups.riscv.org for a while, but that
  list has some problems (it's Google Groups and it's shared over all
  RISC-V software projects). The new infaread.org list is much better.
  We just got it on Wednesday but I used it a bit on Thursday to shake
  out all the configuration problems and it appears to be in working
  order.

  When I updated the mailing list I noticed that the MAINTAINERS file
  was pointing to our github repo, but now that we have a kernel.org
  repo I'd like to point to that instead so I changed that as well.
  We'll be centralizing all RISC-V Linux related development here as
  that seems to be the saner way to go about it.

  I can understand if it's too late to get this into 4.15, but given
  that it's not a code change I was hoping it'd still be OK. It would be
  nice to have the new mailing list and git repo in the release tarballs
  so when people start to find bugs they'll get to the right place"

* tag 'riscv-for-linus-4.15-maintainers' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
  Update the RISC-V MAINTAINERS file
2018-01-26 15:10:50 -08:00
Linus Torvalds
ba804bb4b7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) The per-network-namespace loopback device, and thus its namespace,
    can have its teardown deferred for a long time if a kernel created
    TCP socket closes and the namespace is exiting meanwhile. The kernel
    keeps trying to finish the close sequence until it times out (which
    takes quite some time).

    Fix this by forcing the socket closed in this situation, from Dan
    Streetman.

 2) Fix regression where we're trying to invoke the update_pmtu method
    on route types (in this case metadata tunnel routes) that don't
    implement the dst_ops method. Fix from Nicolas Dichtel.

 3) Fix long standing memory corruption issues in r8169 driver by
    performing the chip statistics DMA programming more correctly. From
    Francois Romieu.

 4) Handle local broadcast sends over VRF routes properly, from David
    Ahern.

 5) Don't refire the DCCP CCID2 timer endlessly, otherwise the socket
    can never be released. From Alexey Kodanev.

 6) Set poll flags properly in VSOCK protocol layer, from Stefan
    Hajnoczi.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  VSOCK: set POLLOUT | POLLWRNORM for TCP_CLOSING
  dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state
  net: vrf: Add support for sends to local broadcast address
  r8169: fix memory corruption on retrieval of hardware statistics.
  net: don't call update_pmtu unconditionally
  net: tcp: close sock if net namespace is exiting
2018-01-26 09:03:16 -08:00
Linus Torvalds
db218549e6 vc4 and nouveau fixes
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Merge tag 'drm-fixes-for-v4.15-rc10-2' of git://people.freedesktop.org/~airlied/linux

Pull drm fixes from Dave Airlie:
 "A fairly urgent nouveau regression fix for broken irqs across
  suspend/resume came in. This was broken before but a patch in 4.15 has
  made it much more obviously broken and now s/r fails a lot more often.

  The fix removes freeing the irq across s/r which never should have
  been done anyways.

  Also two vc4 fixes for a NULL deference and some misrendering /
  flickering on screen"

* tag 'drm-fixes-for-v4.15-rc10-2' of git://people.freedesktop.org/~airlied/linux:
  drm/nouveau: Move irq setup/teardown to pci ctor/dtor
  drm/vc4: Fix NULL pointer dereference in vc4_save_hang_state()
  drm/vc4: Flush the caches before the bin jobs, as well.
2018-01-26 08:59:57 -08:00
Stefan Hajnoczi
ba3169fc75 VSOCK: set POLLOUT | POLLWRNORM for TCP_CLOSING
select(2) with wfds but no rfds must return when the socket is shut down
by the peer.  This way userspace notices socket activity and gets -EPIPE
from the next write(2).

Currently select(2) does not return for virtio-vsock when a SEND+RCV
shutdown packet is received.  This is because vsock_poll() only sets
POLLOUT | POLLWRNORM for TCP_CLOSE, not the TCP_CLOSING state that the
socket is in when the shutdown is received.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-26 11:16:27 -05:00
Alexey Kodanev
dd5684ecae dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state
ccid2_hc_tx_rto_expire() timer callback always restarts the timer
again and can run indefinitely (unless it is stopped outside), and after
commit 120e9dabaf ("dccp: defer ccid_hc_tx_delete() at dismantle time"),
which moved ccid_hc_tx_delete() (also includes sk_stop_timer()) from
dccp_destroy_sock() to sk_destruct(), this started to happen quite often.
The timer prevents releasing the socket, as a result, sk_destruct() won't
be called.

Found with LTP/dccp_ipsec tests running on the bonding device,
which later couldn't be unloaded after the tests were completed:

  unregister_netdevice: waiting for bond0 to become free. Usage count = 148

Fixes: 2a91aa3967 ("[DCCP] CCID2: Initial CCID2 (TCP-Like) implementation")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-26 11:15:00 -05:00
Palmer Dabbelt
6572cc2bf2
Update the RISC-V MAINTAINERS file
Now that we're upstream in Linux we've been able to make some
infrastructure changes so our port works a bit more like other ports.
Specifically:

* We now have a mailing list specific to the RISC-V Linux port, hosted
  at lists.infreadead.org.
* We now have a kernel.org git tree where work on our port is
  coordinated.

This patch changes the RISC-V maintainers entry to reflect these new
bits of infrastructure.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-26 08:01:24 -08:00
Andy Lutomirski
36b3a77268 x86/mm/64: Tighten up vmalloc_fault() sanity checks on 5-level kernels
On a 5-level kernel, if a non-init mm has a top-level entry, it needs to
match init_mm's, but the vmalloc_fault() code skipped over the BUG_ON()
that would have checked it.

While we're at it, get rid of the rather confusing 4-level folded "pgd"
logic.

Cleans-up: b50858ce3e ("x86/mm/vmalloc: Add 5-level paging support")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Neil Berrington <neil.berrington@datacore.com>
Link: https://lkml.kernel.org/r/2ae598f8c279b0a29baf75df207e6f2fdddc0a1b.1516914529.git.luto@kernel.org
2018-01-26 15:56:23 +01:00
Andy Lutomirski
5beda7d54e x86/mm/64: Fix vmapped stack syncing on very-large-memory 4-level systems
Neil Berrington reported a double-fault on a VM with 768GB of RAM that uses
large amounts of vmalloc space with PTI enabled.

The cause is that load_new_mm_cr3() was never fixed to take the 5-level pgd
folding code into account, so, on a 4-level kernel, the pgd synchronization
logic compiles away to exactly nothing.

Interestingly, the problem doesn't trigger with nopti.  I assume this is
because the kernel is mapped with global pages if we boot with nopti.  The
sequence of operations when we create a new task is that we first load its
mm while still running on the old stack (which crashes if the old stack is
unmapped in the new mm unless the TLB saves us), then we call
prepare_switch_to(), and then we switch to the new stack.
prepare_switch_to() pokes the new stack directly, which will populate the
mapping through vmalloc_fault().  I assume that we're getting lucky on
non-PTI systems -- the old stack's TLB entry stays alive long enough to
make it all the way through prepare_switch_to() and switch_to() so that we
make it to a valid stack.

Fixes: b50858ce3e ("x86/mm/vmalloc: Add 5-level paging support")
Reported-and-tested-by: Neil Berrington <neil.berrington@datacore.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: stable@vger.kernel.org
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/346541c56caed61abbe693d7d2742b4a380c5001.1516914529.git.luto@kernel.org
2018-01-26 15:56:23 +01:00
Dave Airlie
baa35cc322 Merge branch 'linux-4.15' of git://github.com/skeggsb/linux into drm-fixes
Single irq regression fix
* 'linux-4.15' of git://github.com/skeggsb/linux:
  drm/nouveau: Move irq setup/teardown to pci ctor/dtor
2018-01-26 15:27:07 +10:00
David Ahern
1e19c4d689 net: vrf: Add support for sends to local broadcast address
Sukumar reported that sends to the local broadcast address
(255.255.255.255) are broken. Check for the address in vrf driver
and do not redirect to the VRF device - similar to multicast
packets.

With this change sockets can use SO_BINDTODEVICE to specify an
egress interface and receive responses. Note: the egress interface
can not be a VRF device but needs to be the enslaved device.

https://bugzilla.kernel.org/show_bug.cgi?id=198521

Reported-by: Sukumar Gopalakrishnan <sukumarg1973@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-25 21:51:03 -05:00
Francois Romieu
a78e93661c r8169: fix memory corruption on retrieval of hardware statistics.
Hardware statistics retrieval hurts in tight invocation loops.

Avoid extraneous write and enforce strict ordering of writes targeted to
the tally counters dump area address registers.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Tested-by: Oliver Freyermuth <o.freyermuth@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-25 21:34:04 -05:00
Linus Torvalds
993ca2068b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input fixes from Dmitry Torokhov:
 "The main item is that we try to better handle the newer trackpoints on
  Lenovo devices that are now being produced by Elan/ALPS/NXP and only
  implement a small subset of the original IBM trackpoint controls"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Revert "Input: synaptics_rmi4 - use devm_device_add_group() for attributes in F01"
  Input: trackpoint - only expose supported controls for Elan, ALPS and NXP
  Input: trackpoint - force 3 buttons if 0 button is reported
  Input: xpad - add support for PDP Xbox One controllers
  Input: stmfts,s6sy671 - add SPDX identifier
2018-01-25 17:30:47 -08:00
Martin Brandenburg
6793f1c450 orangefs: fix deadlock; do not write i_size in read_iter
After do_readv_writev, the inode cache is invalidated anyway, so i_size
will never be read.  It will be fetched from the server which will also
know about updates from other machines.

Fixes deadlock on 32-bit SMP.

See https://marc.info/?l=linux-fsdevel&m=151268557427760&w=2

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-25 17:26:24 -08:00
Lyude Paul
0fd189a95f drm/nouveau: Move irq setup/teardown to pci ctor/dtor
For a while we've been having issues with seemingly random interrupts
coming from nvidia cards when resuming them. Originally the fix for this
was thought to be just re-arming the MSI interrupt registers right after
re-allocating our IRQs, however it seems a lot of what we do is both
wrong and not even nessecary.

This was made apparent by what appeared to be a regression in the
mainline kernel that started introducing suspend/resume issues for
nouveau:

        a0c9259dc4 (irq/matrix: Spread interrupts on allocation)

After this commit was introduced, we started getting interrupts from the
GPU before we actually re-allocated our own IRQ (see references below)
and assigned the IRQ handler. Investigating this turned out that the
problem was not with the commit, but the fact that nouveau even
free/allocates it's irqs before and after suspend/resume.

For starters: drivers in the linux kernel haven't had to handle
freeing/re-allocating their IRQs during suspend/resume cycles for quite
a while now. Nouveau seems to be one of the few drivers left that still
does this, despite the fact there's no reason we actually need to since
disabling interrupts from the device side should be enough, as the
kernel is already smart enough to know to disable host-side interrupts
for us before going into suspend. Since we were tearing down our IRQs by
hand however, that means there was a short period during resume where
interrupts could be received before we re-allocated our IRQ which would
lead to us getting an unhandled IRQ. Since we never handle said IRQ and
re-arm the interrupt registers, this would cause us to miss all of the
interrupts from the GPU and cause our init process to start timing out
on anything requiring interrupts.

So, since this whole setup/teardown every suspend/resume cycle is
useless anyway, move irq setup/teardown into the pci subdev's ctor/dtor
functions instead so they're only called at driver load and driver
unload. This should fix most of the issues with pending interrupts on
resume, along with getting suspend/resume for nouveau to work again.

As well, this probably means we can also just remove the msi rearm call
inside nvkm_pci_init(). But since our main focus here is to fix
suspend/resume before 4.15, we'll save that for a later patch.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Karol Herbst <kherbst@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
2018-01-26 09:44:39 +10:00
Nicolas Dichtel
f15ca723c1 net: don't call update_pmtu unconditionally
Some dst_ops (e.g. md_dst_ops)) doesn't set this handler. It may result to:
"BUG: unable to handle kernel NULL pointer dereference at           (null)"

Let's add a helper to check if update_pmtu is available before calling it.

Fixes: 52a589d51f ("geneve: update skb dst pmtu on tx path")
Fixes: a93bf0ff44 ("vxlan: update skb dst pmtu on tx path")
CC: Roman Kapl <code@rkapl.cz>
CC: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-25 16:27:34 -05:00
Linus Torvalds
6e20630e30 KVM fixes for v4.15(-rc10)
Fix races and potential use after free in the s390 cmma migration code.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Radim Krčmář:
 "Fix races and a potential use after free in the s390 cmma migration
  code"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: s390: add proper locking for CMMA migration bitmap
2018-01-25 09:32:10 -08:00
Linus Torvalds
525273fb2e for-4.15
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Merge tag 'for-4.15-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fix from David Sterba:
 "It's been reported recently that readdir can list stale entries under
  some conditions. Fix it."

* tag 'for-4.15-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix stale entries in readdir
2018-01-25 09:03:10 -08:00
Dan Streetman
4ee806d511 net: tcp: close sock if net namespace is exiting
When a tcp socket is closed, if it detects that its net namespace is
exiting, close immediately and do not wait for FIN sequence.

For normal sockets, a reference is taken to their net namespace, so it will
never exit while the socket is open.  However, kernel sockets do not take a
reference to their net namespace, so it may begin exiting while the kernel
socket is still open.  In this case if the kernel socket is a tcp socket,
it will stay open trying to complete its close sequence.  The sock's dst(s)
hold a reference to their interface, which are all transferred to the
namespace's loopback interface when the real interfaces are taken down.
When the namespace tries to take down its loopback interface, it hangs
waiting for all references to the loopback interface to release, which
results in messages like:

unregister_netdevice: waiting for lo to become free. Usage count = 1

These messages continue until the socket finally times out and closes.
Since the net namespace cleanup holds the net_mutex while calling its
registered pernet callbacks, any new net namespace initialization is
blocked until the current net namespace finishes exiting.

After this change, the tcp socket notices the exiting net namespace, and
closes immediately, releasing its dst(s) and their reference to the
loopback interface, which lets the net namespace continue exiting.

Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1711407
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=97811
Signed-off-by: Dan Streetman <ddstreet@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-25 10:56:45 -05:00
Peter Zijlstra
efe951d3de perf/x86: Fix perf,x86,cpuhp deadlock
More lockdep gifts, a 5-way lockup race:

	perf_event_create_kernel_counter()
	  perf_event_alloc()
	    perf_try_init_event()
	      x86_pmu_event_init()
		__x86_pmu_event_init()
		  x86_reserve_hardware()
 #0		    mutex_lock(&pmc_reserve_mutex);
		    reserve_ds_buffer()
 #1		      get_online_cpus()

	perf_event_release_kernel()
	  _free_event()
	    hw_perf_event_destroy()
	      x86_release_hardware()
 #0		mutex_lock(&pmc_reserve_mutex)
		release_ds_buffer()
 #1		  get_online_cpus()

 #1	do_cpu_up()
	  perf_event_init_cpu()
 #2	    mutex_lock(&pmus_lock)
 #3	    mutex_lock(&ctx->mutex)

	sys_perf_event_open()
	  mutex_lock_double()
 #3	    mutex_lock(ctx->mutex)
 #4	    mutex_lock_nested(ctx->mutex, 1);

	perf_try_init_event()
 #4	  mutex_lock_nested(ctx->mutex, 1)
	  x86_pmu_event_init()
	    intel_pmu_hw_config()
	      x86_add_exclusive()
 #0		mutex_lock(&pmc_reserve_mutex)

Fix it by using ordering constructs instead of locking.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-25 14:48:30 +01:00