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2124 commits

Author SHA1 Message Date
Xunlei Pang 203e9e4121 kexec: move vmcoreinfo out of the kernel's .bss section
As Eric said,
 "what we need to do is move the variable vmcoreinfo_note out of the
  kernel's .bss section. And modify the code to regenerate and keep this
  information in something like the control page.

  Definitely something like this needs a page all to itself, and ideally
  far away from any other kernel data structures. I clearly was not
  watching closely the data someone decided to keep this silly thing in
  the kernel's .bss section."

This patch allocates extra pages for these vmcoreinfo_XXX variables, one
advantage is that it enhances some safety of vmcoreinfo, because
vmcoreinfo now is kept far away from other kernel data structures.

Link: http://lkml.kernel.org/r/1493281021-20737-1-git-send-email-xlpang@redhat.com
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Suggested-by: Eric Biederman <ebiederm@xmission.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:25:59 -07:00
Linus Torvalds 5518b69b76 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Reasonably busy this cycle, but perhaps not as busy as in the 4.12
  merge window:

   1) Several optimizations for UDP processing under high load from
      Paolo Abeni.

   2) Support pacing internally in TCP when using the sch_fq packet
      scheduler for this is not practical. From Eric Dumazet.

   3) Support mutliple filter chains per qdisc, from Jiri Pirko.

   4) Move to 1ms TCP timestamp clock, from Eric Dumazet.

   5) Add batch dequeueing to vhost_net, from Jason Wang.

   6) Flesh out more completely SCTP checksum offload support, from
      Davide Caratti.

   7) More plumbing of extended netlink ACKs, from David Ahern, Pablo
      Neira Ayuso, and Matthias Schiffer.

   8) Add devlink support to nfp driver, from Simon Horman.

   9) Add RTM_F_FIB_MATCH flag to RTM_GETROUTE queries, from Roopa
      Prabhu.

  10) Add stack depth tracking to BPF verifier and use this information
      in the various eBPF JITs. From Alexei Starovoitov.

  11) Support XDP on qed device VFs, from Yuval Mintz.

  12) Introduce BPF PROG ID for better introspection of installed BPF
      programs. From Martin KaFai Lau.

  13) Add bpf_set_hash helper for TC bpf programs, from Daniel Borkmann.

  14) For loads, allow narrower accesses in bpf verifier checking, from
      Yonghong Song.

  15) Support MIPS in the BPF selftests and samples infrastructure, the
      MIPS eBPF JIT will be merged in via the MIPS GIT tree. From David
      Daney.

  16) Support kernel based TLS, from Dave Watson and others.

  17) Remove completely DST garbage collection, from Wei Wang.

  18) Allow installing TCP MD5 rules using prefixes, from Ivan
      Delalande.

  19) Add XDP support to Intel i40e driver, from Björn Töpel

  20) Add support for TC flower offload in nfp driver, from Simon
      Horman, Pieter Jansen van Vuuren, Benjamin LaHaise, Jakub
      Kicinski, and Bert van Leeuwen.

  21) IPSEC offloading support in mlx5, from Ilan Tayari.

  22) Add HW PTP support to macb driver, from Rafal Ozieblo.

  23) Networking refcount_t conversions, From Elena Reshetova.

  24) Add sock_ops support to BPF, from Lawrence Brako. This is useful
      for tuning the TCP sockopt settings of a group of applications,
      currently via CGROUPs"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1899 commits)
  net: phy: dp83867: add workaround for incorrect RX_CTRL pin strap
  dt-bindings: phy: dp83867: provide a workaround for incorrect RX_CTRL pin strap
  cxgb4: Support for get_ts_info ethtool method
  cxgb4: Add PTP Hardware Clock (PHC) support
  cxgb4: time stamping interface for PTP
  nfp: default to chained metadata prepend format
  nfp: remove legacy MAC address lookup
  nfp: improve order of interfaces in breakout mode
  net: macb: remove extraneous return when MACB_EXT_DESC is defined
  bpf: add missing break in for the TCP_BPF_SNDCWND_CLAMP case
  bpf: fix return in load_bpf_file
  mpls: fix rtm policy in mpls_getroute
  net, ax25: convert ax25_cb.refcount from atomic_t to refcount_t
  net, ax25: convert ax25_route.refcount from atomic_t to refcount_t
  net, ax25: convert ax25_uid_assoc.refcount from atomic_t to refcount_t
  net, sctp: convert sctp_ep_common.refcnt from atomic_t to refcount_t
  net, sctp: convert sctp_transport.refcnt from atomic_t to refcount_t
  net, sctp: convert sctp_chunk.refcnt from atomic_t to refcount_t
  net, sctp: convert sctp_datamsg.refcnt from atomic_t to refcount_t
  net, sctp: convert sctp_auth_bytes.refcnt from atomic_t to refcount_t
  ...
2017-07-05 12:31:59 -07:00
Linus Torvalds 9a9594efe5 Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull SMP hotplug updates from Thomas Gleixner:
 "This update is primarily a cleanup of the CPU hotplug locking code.

  The hotplug locking mechanism is an open coded RWSEM, which allows
  recursive locking. The main problem with that is the recursive nature
  as it evades the full lockdep coverage and hides potential deadlocks.

  The rework replaces the open coded RWSEM with a percpu RWSEM and
  establishes full lockdep coverage that way.

  The bulk of the changes fix up recursive locking issues and address
  the now fully reported potential deadlocks all over the place. Some of
  these deadlocks have been observed in the RT tree, but on mainline the
  probability was low enough to hide them away."

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
  cpu/hotplug: Constify attribute_group structures
  powerpc: Only obtain cpu_hotplug_lock if called by rtasd
  ARM/hw_breakpoint: Fix possible recursive locking for arch_hw_breakpoint_init
  cpu/hotplug: Remove unused check_for_tasks() function
  perf/core: Don't release cred_guard_mutex if not taken
  cpuhotplug: Link lock stacks for hotplug callbacks
  acpi/processor: Prevent cpu hotplug deadlock
  sched: Provide is_percpu_thread() helper
  cpu/hotplug: Convert hotplug locking to percpu rwsem
  s390: Prevent hotplug rwsem recursion
  arm: Prevent hotplug rwsem recursion
  arm64: Prevent cpu hotplug rwsem recursion
  kprobes: Cure hotplug lock ordering issues
  jump_label: Reorder hotplug lock and jump_label_lock
  perf/tracing/cpuhotplug: Fix locking order
  ACPI/processor: Use cpu_hotplug_disable() instead of get_online_cpus()
  PCI: Replace the racy recursion prevention
  PCI: Use cpu_hotplug_disable() instead of get_online_cpus()
  perf/x86/intel: Drop get_online_cpus() in intel_snb_check_microcode()
  x86/perf: Drop EXPORT of perf_check_microcode
  ...
2017-07-03 18:08:06 -07:00
Linus Torvalds e0f3e8f14d Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "The bulk of the s390 patches for 4.13. Some new things but mostly bug
  fixes and cleanups. Noteworthy changes:

   - The SCM block driver is converted to blk-mq

   - Switch s390 to 5 level page tables. The virtual address space for a
     user space process can now have up to 16EB-4KB.

   - Introduce a ELF phdr flag for qemu to avoid the global
     vm.alloc_pgste which forces all processes to large page tables

   - A couple of PCI improvements to improve error recovery

   - Included is the merge of the base support for proper machine checks
     for KVM"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (52 commits)
  s390/dasd: Fix faulty ENODEV for RO sysfs attribute
  s390/pci: recognize name clashes with uids
  s390/pci: provide more debug information
  s390/pci: fix handling of PEC 306
  s390/pci: improve pci hotplug
  s390/pci: introduce clp_get_state
  s390/pci: improve error handling during fmb (de)registration
  s390/pci: improve unreg_ioat error handling
  s390/pci: improve error handling during interrupt deregistration
  s390/pci: don't cleanup in arch_setup_msi_irqs
  KVM: s390: Backup the guest's machine check info
  s390/nmi: s390: New low level handling for machine check happening in guest
  s390/fpu: export save_fpu_regs for all configs
  s390/kvm: avoid global config of vm.alloc_pgste=1
  s390: rename struct psw_bits members
  s390: rename psw_bits enums
  s390/mm: use correct address space when enabling DAT
  s390/cio: introduce io_subchannel_type
  s390/ipl: revert Load Normal semantics for LPAR CCW-type re-IPL
  s390/dumpstack: remove raw stack dump
  ...
2017-07-03 15:39:36 -07:00
Linus Torvalds 81e3e04489 UUID/GUID updates:
- introduce the new uuid_t/guid_t types that are going to replace
    the somewhat confusing uuid_be/uuid_le types and make the terminology
    fit the various specs, as well as the userspace libuuid library.
    (me, based on a previous version from Amir)
  - consolidated generic uuid/guid helper functions lifted from XFS
    and libnvdimm (Amir and me)
  - conversions to the new types and helpers (Amir, Andy and me)
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Merge tag 'uuid-for-4.13' of git://git.infradead.org/users/hch/uuid

Pull uuid subsystem from Christoph Hellwig:
 "This is the new uuid subsystem, in which Amir, Andy and I have started
  consolidating our uuid/guid helpers and improving the types used for
  them. Note that various other subsystems have pulled in this tree, so
  I'd like it to go in early.

  UUID/GUID summary:

   - introduce the new uuid_t/guid_t types that are going to replace the
     somewhat confusing uuid_be/uuid_le types and make the terminology
     fit the various specs, as well as the userspace libuuid library.
     (me, based on a previous version from Amir)

   - consolidated generic uuid/guid helper functions lifted from XFS and
     libnvdimm (Amir and me)

   - conversions to the new types and helpers (Amir, Andy and me)"

* tag 'uuid-for-4.13' of git://git.infradead.org/users/hch/uuid: (34 commits)
  ACPI: hns_dsaf_acpi_dsm_guid can be static
  mmc: sdhci-pci: make guid intel_dsm_guid static
  uuid: Take const on input of uuid_is_null() and guid_is_null()
  thermal: int340x_thermal: fix compile after the UUID API switch
  thermal: int340x_thermal: Switch to use new generic UUID API
  acpi: always include uuid.h
  ACPI: Switch to use generic guid_t in acpi_evaluate_dsm()
  ACPI / extlog: Switch to use new generic UUID API
  ACPI / bus: Switch to use new generic UUID API
  ACPI / APEI: Switch to use new generic UUID API
  acpi, nfit: Switch to use new generic UUID API
  MAINTAINERS: add uuid entry
  tmpfs: generate random sb->s_uuid
  scsi_debug: switch to uuid_t
  nvme: switch to uuid_t
  sysctl: switch to use uuid_t
  partitions/ldm: switch to use uuid_t
  overlayfs: use uuid_t instead of uuid_be
  fs: switch ->s_uuid to uuid_t
  ima/policy: switch to use uuid_t
  ...
2017-07-03 09:55:26 -07:00
David S. Miller b079115937 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
A set of overlapping changes in macvlan and the rocker
driver, nothing serious.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-30 12:43:08 -04:00
Tobias Klauser 6474924e2b arch: remove unused macro/function thread_saved_pc()
The only user of thread_saved_pc() in non-arch-specific code was removed
in commit 8243d55977 ("sched/core: Remove pointless printout in
sched_show_task()").  Remove the implementations as well.

Some architectures use thread_saved_pc() in their arch-specific code.
Leave their thread_saved_pc() intact.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-28 16:13:57 -07:00
Martin Schwidefsky 9e293b5a70 s390,kvm: provide plumbing for machines checks when running guests
This provides the basic plumbing for handling machine checks when
 running guests
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Merge tag 'nmiforkvm' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into features

Pull kvm patches from Christian Borntraeger:
"s390,kvm: provide plumbing for machines checks when running guests"

This provides the basic plumbing for handling machine checks when
running guests
2017-06-28 12:57:47 +02:00
QingFeng Hao da72ca4d40 KVM: s390: Backup the guest's machine check info
When a machine check happens in the guest, related mcck info (mcic,
external damage code, ...) is stored in the vcpu's lowcore on the host.
Then the machine check handler's low-level part is executed, followed
by the high-level part.

If the high-level part's execution is interrupted by a new machine check
happening on the same vcpu on the host, the mcck info in the lowcore is
overwritten with the new machine check's data.

If the high-level part's execution is scheduled to a different cpu,
the mcck info in the lowcore is uncertain.

Therefore, for both cases, the further reinjection to the guest will use
the wrong data.
Let's backup the mcck info in the lowcore to the sie page
for further reinjection, so that the right data will be used.

Add new member into struct sie_page to store related machine check's
info of mcic, failing storage address and external damage code.

Signed-off-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-06-27 16:05:38 +02:00
QingFeng Hao c929500d7a s390/nmi: s390: New low level handling for machine check happening in guest
Add the logic to check if the machine check happens when the guest is
running. If yes, set the exit reason -EINTR in the machine check's
interrupt handler. Refactor s390_do_machine_check to avoid panicing
the host for some kinds of machine checks which happen
when guest is running.
Reinject the instruction processing damage's machine checks including
Delayed Access Exception instead of damaging the host if it happens
in the guest because it could be caused by improper update on TLB entry
or other software case and impacts the guest only.

Signed-off-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-06-27 16:05:27 +02:00
Julian Wiedmann 1b03047816 s390/diag: add diag26c support
Implement support for the hypervisor diagnose 0x26c
('Access Certain System Information').
It passes a request buffer and a subfunction code, and receives
a response buffer and a return code.

Also add the scaffolding for the 'MAC Services' subfunction.
It may be used by network devices to obtain a hypervisor-managed
MAC address.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-20 15:44:15 -04:00
Heiko Carstens 4130b28f56 s390/ipl: revert Load Normal semantics for LPAR CCW-type re-IPL
This reverts the two commits

7afbeb6df2 ("s390/ipl: always use load normal for CCW-type re-IPL")
0f7451ff3a ("s390/ipl: use load normal for LPAR re-ipl")

The two commits did not take into account that behavior of standby
memory changes fundamentally if the re-IPL method is changed from
Load Clear to Load Normal.

In case of the old re-IPL clear method all memory that was initially
in standby state will be put into standby state again within the
re-IPL process. Or in other words: memory that was brought online
before a re-IPL will be offline again after a reboot.

Given that we use different re-IPL methods depending on the hypervisor
and CCW-type vs SCSI re-IPL it is not easy to tell in advance when and
why memory will stay online or will be offline after a re-IPL.
This does also have other side effects, since memory that is online
from the beginning will be in ZONE_NORMAL by default vs ZONE_MOVABLE
for memory that is offline.

Therefore, before the change, a user could online and offline memory
easily since standby memory was always in ZONE_NORMAL.  After the
change, and a re-IPL, this depended on which memory parts were online
before the re-IPL.

From a usability point of view the current behavior is more than
suboptimal. Therefore revert these changes until we have a better
solution and get back to a consistent behavior. The bad thing about
this is that the time required for a re-IPL will be significantly
increased for configurations with several 100GB or 1TB of memory.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-14 15:35:31 +02:00
Martin Schwidefsky f044f4c588 s390/fpu: export save_fpu_regs for all configs
The save_fpu_regs function is a general API that is supposed to be
usable for modules as well. Remove the #ifdef that hides the symbol
for CONFIG_KVM=n.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-13 13:03:43 +02:00
Martin Schwidefsky 23fefe119c s390/kvm: avoid global config of vm.alloc_pgste=1
The system control vm.alloc_pgste is used to control the size of the
page tables, either 2K or 4K. The idea is that a KVM host sets the
vm.alloc_pgste control to 1 which causes *all* new processes to run
with 4K page tables. For a non-kvm system the control should stay off
to save on memory used for page tables.

Trouble is that distributions choose to set the control globally to
be able to run KVM guests. This wastes memory on non-KVM systems.

Introduce the PT_S390_PGSTE ELF segment type to "mark" the qemu
executable with it. All executables with this (empty) segment in
its ELF phdr array will be started with 4K page tables. Any executable
without PT_S390_PGSTE will run with the default 2K page tables.

This removes the need to set vm.alloc_pgste=1 for a KVM host and
minimizes the waste of memory for page tables.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-13 13:03:41 +02:00
Heiko Carstens a752598254 s390: rename struct psw_bits members
Rename a couple of the struct psw_bits members so it is more obvious
for what they are good. Initially I thought using the single character
names from the PoP would be sufficient and obvious, but admittedly
that is not true.

The current implementation is not easy to use, if one has to look into
the source file to figure out which member represents the 'per' bit
(which is the 'r' member).

Therefore rename the members to sane names that are identical to the
uapi psw mask defines:

r -> per
i -> io
e -> ext
t -> dat
m -> mcheck
w -> wait
p -> pstate

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:26:02 +02:00
Heiko Carstens 8bb3fdd686 s390: rename psw_bits enums
The address space enums that must be used when modifying the address
space part of a psw with the psw_bits() macro can easily be confused
with the psw defines that are used to mask and compare directly the
mask part of a psw.
We have e.g. PSW_AS_PRIMARY vs PSW_ASC_PRIMARY.

To avoid confusion rename the PSW_AS_* enums to PSW_BITS_AS_*.

In addition also rename the PSW_AMODE_* enums, so they also follow the
same naming scheme: PSW_BITS_AMODE_*.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:26:02 +02:00
Heiko Carstens ead1dec8ed s390/ipl: revert Load Normal semantics for LPAR CCW-type re-IPL
This reverts the two commits

7afbeb6df2 ("s390/ipl: always use load normal for CCW-type re-IPL")
0f7451ff3a ("s390/ipl: use load normal for LPAR re-ipl")

The two commits did not take into account that behavior of standby
memory changes fundamentally if the re-IPL method is changed from
Load Clear to Load Normal.

In case of the old re-IPL clear method all memory that was initially
in standby state will be put into standby state again within the
re-IPL process. Or in other words: memory that was brought online
before a re-IPL will be offline again after a reboot.

Given that we use different re-IPL methods depending on the hypervisor
and CCW-type vs SCSI re-IPL it is not easy to tell in advance when and
why memory will stay online or will be offline after a re-IPL.
This does also have other side effects, since memory that is online
from the beginning will be in ZONE_NORMAL by default vs ZONE_MOVABLE
for memory that is offline.

Therefore, before the change, a user could online and offline memory
easily since standby memory was always in ZONE_NORMAL.  After the
change, and a re-IPL, this depended on which memory parts were online
before the re-IPL.

From a usability point of view the current behavior is more than
suboptimal. Therefore revert these changes until we have a better
solution and get back to a consistent behavior. The bad thing about
this is that the time required for a re-IPL will be significantly
increased for configurations with several 100GB or 1TB of memory.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:26:01 +02:00
Heiko Carstens 2b7b9817c2 s390/dumpstack: remove raw stack dump
Remove raw stack dumps that are printed before call traces in case of
a warning, or the 'l' sysrq trigger (show a stack backtrace for all
active CPUs).

Besides that a raw stack dump should not be shown for the 'l' sysrq
trigger the value of the dump is close to zero. That's also why we
don't print it in case of a panic since ages anymore. That this is
still printed on warnings is just a leftover. So get rid of this
completely.

The following won't be printed anymore with this change:

Stack:
       00000000bbc4fbc8 00000000bbc4fc58 0000000000000003 0000000000000000
       00000000bbc4fcf8 00000000bbc4fc70 00000000bbc4fc70 0000000000000020
       000000007fe00098 00000000bfe8be00 00000000bbc4fe94 000000000000000a
       000000000000000c 00000000bbc4fcc0 0000000000000000 0000000000000000
       000000000095b930 0000000000113366 00000000bbc4fc58 00000000bbc4fca0

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:26:01 +02:00
Thomas Richter c39457ff1f s390/perf: fix null string in perf list pmu command
Command 'perf list pmu' displays events which contain
an invalid string "(null)=xxx", where xxx is the pmu event
name, for example:
   cpum_cf/AES_BLOCKED_CYCLES,(null)=AES_BLOCKED_CYCLES/
This is not correct, the invalid string should not be
displayed at all.

It is caused by an obsolete term in the
sysfs attribute file for each s390 CPUMF counter event.
Reading from the sysfs file also displays the event
name.

Fix this by omitting the event name.  This patch makes
s390 CPUMF sysfs files consistent with other plattforms.

This is an interface change between user and kernel
but does not break anything. Reading from a counter event
sysfs file should only list terms mentioned in the
/sys/bus/event_source/devices/<cpumf>/format directory.
Name is not listed.

Reported-by: Zvonko Kosic <zvonko.kosic@de.ibm.com>
Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:26:00 +02:00
Martin Schwidefsky f5bbd72198 s390/ptrace: guarded storage regset for the current task
The regset functions for guarded storage are supposed to work on
the current task as well. For task == current add the required
load and store instructions for the guarded storage control block.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:25:59 +02:00
Christian Borntraeger 9cf8edb7a3 s390/smp: fix false positive kmemleak of mcesa data structure
I get number of CPUs - 1 kmemleak hits like

unreferenced object 0x37ec6f000 (size 1024):
  comm "swapper/0", pid 1, jiffies 4294937330 (age 889.690s)
  hex dump (first 32 bytes):
    6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
    6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
  backtrace:
    [<000000000034a848>] kmem_cache_alloc+0x2b8/0x3d0
    [<00000000001164de>] __cpu_up+0x456/0x488
    [<000000000016f60c>] bringup_cpu+0x4c/0xd0
    [<000000000016d5d2>] cpuhp_invoke_callback+0xe2/0x9e8
    [<000000000016f3c6>] cpuhp_up_callbacks+0x5e/0x110
    [<000000000016f988>] _cpu_up+0xe0/0x158
    [<000000000016faf0>] do_cpu_up+0xf0/0x110
    [<0000000000dae1ee>] smp_init+0x126/0x130
    [<0000000000d9bd04>] kernel_init_freeable+0x174/0x2e0
    [<000000000089fc62>] kernel_init+0x2a/0x148
    [<00000000008adce2>] kernel_thread_starter+0x6/0xc
    [<00000000008adcdc>] kernel_thread_starter+0x0/0xc
    [<ffffffffffffffff>] 0xffffffffffffffff

The pointer of this data structure is stored in the prefix page of that
CPU together with some extra bits ORed into the the low bits.
Mark the data structure as non-leak.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:25:58 +02:00
Martin Schwidefsky 35bb092a91 s390/vdso: use _install_special_mapping to establish vdso
Switch to the improved _install_special_mapping function to install
the vdso mapping. This has two advantages, the arch_vma_name function
is not needed anymore and the vdso vma still has its name after its
memory location has been changed with mremap.

Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:25:57 +02:00
Martin Schwidefsky b29e061bb7 s390/cputime: simplify account_system_index_scaled
The account_system_index_scaled gets two cputime values, a raw value
derived from CPU timer deltas and a scaled value. The scaled value
is always calculated from the raw value, the code can be simplified
by moving the scale_vtime call into account_system_index_scaled.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:25:57 +02:00
Heiko Carstens 92acfb7406 s390: add missing header includes for type checking
Add missing include statements to make sure that prototypes match
implementation. As reported by sparse:

arch/s390/crypto/arch_random.c:18:1:
  warning: symbol 's390_arch_random_available' was not declared. Should it be static?
arch/s390/kernel/traps.c:279:13: warning:
  symbol 'trap_init' was not declared. Should it be static?

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:25:55 +02:00
Christoph Hellwig e64e17a554 S390/sysinfo: use uuid_is_null instead of opencoding it
And switch to use uuid_t instead of the old uuid_be type.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2017-06-05 16:59:06 +02:00
Thomas Gleixner 5d5dbc4ef2 s390: Prevent hotplug rwsem recursion
The text patching functions which are invoked from jump_label and kprobes
code are protected against cpu hotplug at the call sites.

Use stop_machine_cpuslocked() to avoid recursion on the cpu hotplug
rwsem. stop_machine_cpuslocked() contains a lockdep assertion to catch any
unprotected callers.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20170524081549.354513406@linutronix.de
2017-05-26 10:10:46 +02:00
Sebastian Andrzej Siewior 2337e879e8 s390/kernel: Use stop_machine_cpuslocked()
stp_work_fn() holds get_online_cpus() while invoking stop_machine().

stop_machine() invokes get_online_cpus() as well. This is correct, but
prevents the conversion of the hotplug locking to a percpu rwsem.

Use stop_machine_cpuslocked() to avoid the nested call. Convert
*_online_cpus() to the new interfaces while at it.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20170524081548.250203087@linutronix.de
2017-05-26 10:10:41 +02:00
Christian Borntraeger c0e7bb38c0 s390/kvm: do not rely on the ILC on kvm host protection fauls
For most cases a protection exception in the host (e.g. copy
on write or dirty tracking) on the sie instruction will indicate
an instruction length of 4. Turns out that there are some corner
cases (e.g. runtime instrumentation) where this is not necessarily
true and the ILC is unpredictable.

Let's replace our 4 byte rewind_pad with 3 byte nops to prepare for
all possible ILCs.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-17 12:34:03 +02:00
Linus Torvalds 2b6b38b04c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Martin Schwidefsky:

 - convert the debug feature to refcount_t

 - reduce the copy size for strncpy_from_user

 - 8 bug fixes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/virtio: change virtio_feature_desc:features type to __le32
  s390: convert debug_info.ref_count from atomic_t to refcount_t
  s390: move _text symbol to address higher than zero
  s390/qdio: increase string buffer size
  s390/ccwgroup: increase string buffer size
  s390/topology: let topology_mnest_limit() return unsigned char
  s390/uaccess: use sane length for __strncpy_from_user()
  s390/uprobes: fix compile for !KPROBES
  s390/ftrace: fix compile for !MODULES
  s390/cputime: fix incorrect system time
2017-05-16 09:24:44 -07:00
Elena Reshetova efc0c21c9e s390: convert debug_info.ref_count from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-11 16:35:32 +02:00
Heiko Carstens d04a4c76f7 s390: move _text symbol to address higher than zero
The perf tool assumes that kernel symbols are never present at address
zero. In fact it assumes if functions that map symbols to addresses
return zero, that the symbol was not found.

Given that s390's _text symbol historically is located at address zero
this yields at least a couple of false errors and warnings in one of
perf's test cases about not present symbols ("perf test 1").

To fix this simply move the _text symbol to address 0x200, just behind
the initial psw and channel program located at the beginning of the
kernel image. This is now hard coded within the linker script.

I tried a nicer solution which moves the initial psw and channel
program into an own section. However that would move the symbols
within the "real" head.text section to different addresses, since the
".org" statements within head.S are relative to the head.text
section. If there is a new section in front, everything else will be
moved. Alternatively I could have adjusted all ".org" statements. But
this current solution seems to be the easiest one, since nobody really
cares where the _text symbol is actually located.

Reported-by: Zvonko Kosic <zkosic@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-09 10:44:38 +02:00
Laura Abbott e6c7c63001 s390: use set_memory.h header
set_memory_* functions have moved to set_memory.h.  Switch to this
explicitly

Link: http://lkml.kernel.org/r/1488920133-27229-5-git-send-email-labbott@redhat.com
Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:13 -07:00
Alexey Dobriyan c311c79799 cpumask: make "nr_cpumask_bits" unsigned
Bit searching functions accept "unsigned long" indices but
"nr_cpumask_bits" is "int" which is signed, so inevitable sign
extensions occur on x86_64.  Those MOVSX are #1 MOVSX bloat by number of
uses across whole kernel.

Change "nr_cpumask_bits" to unsigned, this number can't be negative
after all.  It allows to do implicit zero-extension on x86_64 without
MOVSX.

Change signed comparisons into unsigned comparisons where necessary.

Other uses looks fine because it is either argument passed to a function
or comparison is already unsigned.

Net win on allyesconfig type of kernel: ~2.8 KB (!)

	add/remove: 0/0 grow/shrink: 8/725 up/down: 93/-2926 (-2833)
	function                                     old     new   delta
	xen_exit_mmap                                691     735     +44
	qstat_read                                   426     440     +14
	__cpufreq_cooling_register                  1678    1687      +9
	trace_rb_cpu_prepare                         447     455      +8
	vermagic                                      54      60      +6
	nfp_driver_version                            54      60      +6
	rcu_torture_stats_print                     1147    1151      +4
	find_next_push_cpu                           267     269      +2
	xen_irq_resume                               961     960      -1
				...
	init_vp_index                                946     906     -40
	od_set_powersave_bias                        328     281     -47
	power_cpu_exit                               193     139     -54
	arch_show_interrupts                        3538    3484     -54
	select_idle_sibling                         1558    1471     -87
	Total: Before=158358910, After=158356077, chg -0.00%

Same arguments apply to "nr_cpu_ids" but I haven't yet found enough
courage to delve into this issue (and proper fix may require new type
"cpu_t" which is whole separate story).

Link: http://lkml.kernel.org/r/20170309205322.GA1728@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:11 -07:00
Heiko Carstens 085b6ba0f7 s390/ftrace: fix compile for !MODULES
Fix this compile error if CONFIG_MODULES is disabled:

arch/s390/built-in.o: In function `ftrace_plt_init':
arch/s390/kernel/ftrace.o:(.init.text+0x34cc): undefined reference to `module_alloc'

Reported-by: Rob Landley <rob@landley.net>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-03 09:08:57 +02:00
Martin Schwidefsky 07a63cbe8b s390/cputime: fix incorrect system time
git commit c5328901aa "[S390] entry[64].S improvements" removed
the update of the exit_timer lowcore field from the critical section
cleanup of the .Lsysc_restore/.Lsysc_done and .Lio_restore/.Lio_done
blocks. If the PSW is updated by the critical section cleanup to point to
user space again, the interrupt entry code will do a vtime calculation
after the cleanup completed with an exit_timer value which has *not* been
updated. Due to this incorrect system time deltas are calculated.

If an interrupt occured with an old PSW between .Lsysc_restore/.Lsysc_done
or .Lio_restore/.Lio_done update __LC_EXIT_TIMER with the system entry
time of the interrupt.

Cc: stable@vger.kernel.org # 3.3+
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-03 09:08:57 +02:00
Linus Torvalds 76f1948a79 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull livepatch updates from Jiri Kosina:

 - a per-task consistency model is being added for architectures that
   support reliable stack dumping (extending this, currently rather
   trivial set, is currently in the works).

   This extends the nature of the types of patches that can be applied
   by live patching infrastructure. The code stems from the design
   proposal made [1] back in November 2014. It's a hybrid of SUSE's
   kGraft and RH's kpatch, combining advantages of both: it uses
   kGraft's per-task consistency and syscall barrier switching combined
   with kpatch's stack trace switching. There are also a number of
   fallback options which make it quite flexible.

   Most of the heavy lifting done by Josh Poimboeuf with help from
   Miroslav Benes and Petr Mladek

   [1] https://lkml.kernel.org/r/20141107140458.GA21774@suse.cz

 - module load time patch optimization from Zhou Chengming

 - a few assorted small fixes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: add missing printk newlines
  livepatch: Cancel transition a safe way for immediate patches
  livepatch: Reduce the time of finding module symbols
  livepatch: make klp_mutex proper part of API
  livepatch: allow removal of a disabled patch
  livepatch: add /proc/<pid>/patch_state
  livepatch: change to a per-task consistency model
  livepatch: store function sizes
  livepatch: use kstrtobool() in enabled_store()
  livepatch: move patching functions into patch.c
  livepatch: remove unnecessary object loaded check
  livepatch: separate enabled and patched states
  livepatch/s390: add TIF_PATCH_PENDING thread flag
  livepatch/s390: reorganize TIF thread flag bits
  livepatch/powerpc: add TIF_PATCH_PENDING thread flag
  livepatch/x86: add TIF_PATCH_PENDING thread flag
  livepatch: create temporary klp_update_patch_state() stub
  x86/entry: define _TIF_ALLWORK_MASK flags explicitly
  stacktrace/x86: add function for detecting reliable stack traces
2017-05-02 18:24:16 -07:00
Linus Torvalds b68e7e952f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:

 - three merges for KVM/s390 with changes for vfio-ccw and cpacf. The
   patches are included in the KVM tree as well, let git sort it out.

 - add the new 'trng' random number generator

 - provide the secure key verification API for the pkey interface

 - introduce the z13 cpu counters to perf

 - add a new system call to set up the guarded storage facility

 - simplify TASK_SIZE and arch_get_unmapped_area

 - export the raw STSI data related to CPU topology to user space

 - ... and the usual churn of bug-fixes and cleanups.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (74 commits)
  s390/crypt: use the correct module alias for paes_s390.
  s390/cpacf: Introduce kma instruction
  s390/cpacf: query instructions use unique parameters for compatibility with KMA
  s390/trng: Introduce s390 TRNG device driver.
  s390/crypto: Provide s390 specific arch random functionality.
  s390/crypto: Add new subfunctions to the cpacf PRNO function.
  s390/crypto: Renaming PPNO to PRNO.
  s390/pageattr: avoid unnecessary page table splitting
  s390/mm: simplify arch_get_unmapped_area[_topdown]
  s390/mm: make TASK_SIZE independent from the number of page table levels
  s390/gs: add regset for the guarded storage broadcast control block
  s390/kvm: Add use_cmma field to mm_context_t
  s390/kvm: Add PGSTE manipulation functions
  vfio: ccw: improve error handling for vfio_ccw_mdev_remove
  vfio: ccw: remove unnecessary NULL checks of a pointer
  s390/spinlock: remove compare and delay instruction
  s390/spinlock: use atomic primitives for spinlocks
  s390/cpumf: simplify detection of guest samples
  s390/pci: remove forward declaration
  s390/pci: increase the PCI_NR_FUNCTIONS default
  ...
2017-05-02 09:50:09 -07:00
Linus Torvalds 174ddfd5df Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "The timer departement delivers:

   - more year 2038 rework

   - a massive rework of the arm achitected timer

   - preparatory patches to allow NTP correction of clock event devices
     to avoid early expiry

   - the usual pile of fixes and enhancements all over the place"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (91 commits)
  timer/sysclt: Restrict timer migration sysctl values to 0 and 1
  arm64/arch_timer: Mark errata handlers as __maybe_unused
  Clocksource/mips-gic: Remove redundant non devicetree init
  MIPS/Malta: Probe gic-timer via devicetree
  clocksource: Use GENMASK_ULL in definition of CLOCKSOURCE_MASK
  acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver
  clocksource: arm_arch_timer: add GTDT support for memory-mapped timer
  acpi/arm64: Add memory-mapped timer support in GTDT driver
  clocksource: arm_arch_timer: simplify ACPI support code.
  acpi/arm64: Add GTDT table parse driver
  clocksource: arm_arch_timer: split MMIO timer probing.
  clocksource: arm_arch_timer: add structs to describe MMIO timer
  clocksource: arm_arch_timer: move arch_timer_needs_of_probing into DT init call
  clocksource: arm_arch_timer: refactor arch_timer_needs_probing
  clocksource: arm_arch_timer: split dt-only rate handling
  x86/uv/time: Set ->min_delta_ticks and ->max_delta_ticks
  unicore32/time: Set ->min_delta_ticks and ->max_delta_ticks
  um/time: Set ->min_delta_ticks and ->max_delta_ticks
  tile/time: Set ->min_delta_ticks and ->max_delta_ticks
  score/time: Set ->min_delta_ticks and ->max_delta_ticks
  ...
2017-05-01 16:15:18 -07:00
Martin Schwidefsky e525f8a6e6 s390/gs: add regset for the guarded storage broadcast control block
The guarded storage interface allows to register a control block for
each thread that is activated with the guarded storage broadcast event.
To retrieve the complete state of a process from the kernel a register
set for the stored broadcast control block is required.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-04-21 12:38:56 +02:00
Nicolai Stange 06c546110b s390/time: Set ->min_delta_ticks and ->max_delta_ticks
In preparation for making the clockevents core NTP correction aware,
all clockevent device drivers must set ->min_delta_ticks and
->max_delta_ticks rather than ->min_delta_ns and ->max_delta_ns: a
clockevent device's rate is going to change dynamically and thus, the
ratio of ns to ticks ceases to stay invariant.

Currently, the s390's CPU timer clockevent device is initialized as
follows:

  cd->min_delta_ns    = 1;
  cd->max_delta_ns    = LONG_MAX;

Note that the device's time to cycle conversion factor, i.e.
cd->mult / (2^cd->shift), is approx. equal to 4.

Hence, this would translate to

  cd->min_delta_ticks = 4;
  cd->max_delta_ticks = 4 * LONG_MAX;

However, a minimum value of 1ns is in the range of noise anyway and the
clockevent core will take care of this by increasing it to 1us or so.
Furthermore, 4*LONG_MAX would overflow the unsigned long argument the
clockevent devices gets programmed with.

Thus, initialize ->min_delta_ticks with 1 and ->max_delta_ticks with
ULONG_MAX.

This patch alone doesn't introduce any change in functionality as the
clockevents core still looks exclusively at the (untouched) ->min_delta_ns
and ->max_delta_ns. As soon as this has changed, a followup patch will
purge the initialization of ->min_delta_ns and ->max_delta_ns from this
driver.

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: linux-s390@vger.kernel.org
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2017-04-14 13:11:20 -07:00
Martin Schwidefsky b13de4b7ad s390/spinlock: remove compare and delay instruction
The CAD instruction never worked quite as expected for the spinlock
code. It has been disabled by default with git commit 61b0b01686,
if the "cad" kernel parameter is specified it is enabled for both user
space and the spinlock code. Leave the option to enable the instruction
for user space but remove it from the spinlock code.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-04-12 08:43:33 +02:00
Martin Schwidefsky df26c2e87e s390/cpumf: simplify detection of guest samples
There are three different code levels in regard to the identification
of guest samples. They differ in the way the LPP instruction is used.

1) Old kernels without the LPP instruction. The guest program parameter
   is always zero.
2) Newer kernels load the process pid into the program parameter with LPP.
   The guest program parameter is non-zero if the guest executes in a
   process != idle.
3) The latest kernels load ((1UL << 31) | pid) with LPP to make the value
   non-zero even for the idle task. The guest program parameter is non-zero
   if the guest is running.

All kernels load the process pid to CR4 on context switch. The CPU sampling
code uses the value in CR4 to decide between guest and host samples in case
the guest program parameter is zero. The three cases:

1) CR4==pid, gpp==0
2) CR4==pid, gpp==pid
3) CR4==pid, gpp==((1UL << 31) | pid)

The load-control instruction to load the pid into CR4 is expensive and the
goal is to remove it. To distinguish the host CR4 from the guest pid for
the idle process the maximum value 0xffff for the PASN is used.
This adds a fourth case for a guest OS with an updated kernel:

4) CR4==0xffff, gpp=((1UL << 31) | pid)

The host kernel will have CR4==0xffff and will use (gpp!=0 || CR4!==0xffff)
to identify guest samples. This works nicely with all 4 cases, the only
possible issue would be a guest with an old kernel (gpp==0) and a process
pid of 0xffff. Well, don't do that..

Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-04-05 10:11:38 +02:00
Martin Schwidefsky cab36c262e s390: use 64-bit lctlg to load task pid to cr4 on context switch
The 32-bit lctl instruction is quite a bit slower than the 64-bit
counter part lctlg. Use the faster instruction.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-04-05 07:35:14 +02:00
Linus Torvalds 4ad72555b8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Martin Schwidefsky:
 "Four bug fixes, two of them for stable:

   - avoid initrd corruptions in the kernel decompressor

   - prevent inconsistent dumps if the boot CPU does not have address
     zero

   - fix the new pkey interface added with the merge window for 4.11

   - a fix for a fix, another issue with user copy zero padding"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/uaccess: get_user() should zero on failure (again)
  s390/pkey: Fix wrong handling of secure key with old MKVP
  s390/smp: fix ipl from cpu with non-zero address
  s390/decompressor: fix initrd corruption caused by bss clear
2017-04-03 08:44:43 -07:00
Kees Cook 906f2a51c9 mm: fix section name for .data..ro_after_init
A section name for .data..ro_after_init was added by both:

    commit d07a980c1b ("s390: add proper __ro_after_init support")

and

    commit d7c19b066d ("mm: kmemleak: scan .data.ro_after_init")

The latter adds incorrect wrapping around the existing s390 section, and
came later.  I'd prefer the s390 naming, so this moves the s390-specific
name up to the asm-generic/sections.h and renames the section as used by
kmemleak (and in the future, kernel/extable.c).

Link: http://lkml.kernel.org/r/20170327192213.GA129375@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>	[s390 parts]
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Eddie Kovsky <ewk@edkovsky.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-31 17:13:30 -07:00
Hendrik Brueckner 485527ba57 s390/cpum_cf: make hw_perf_event_update() a void function
The return code of hw_perf_event_update() is not evaluated by
its callers.  Hence, simplify the function by removing the
return code.

Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-03-31 07:53:35 +02:00
Hendrik Brueckner 66a49784f9 s390/cpum_cf: correct variable naming (cleanup)
Make clear that the event definitions relate to the counter
facility (cf) and not to the sampling facility (sf).

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-03-31 07:53:33 +02:00
Hendrik Brueckner 3fc7acebae s390/cpum_cf: add IBM z13 counter event names
Add the event names for the IBM z13/z13s specific CPU-MF counters.

Also improve the merging of the generic and model specific events
so that their sysfs attribute definitions completely reside in
memory.  Hence, flagging the generic event attribute definitions
as initdata too.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-03-31 07:53:32 +02:00
Hendrik Brueckner ee699f329a s390/cpum_cf: add support for the MT-diagnostic counter set (z13)
Complete the IBM z13 support and support counters from the
MT-diagnostic counter set.  Note that this counter set is
available only if SMT is enabled.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-03-31 07:53:30 +02:00
Hendrik Brueckner db17160dce s390/cpum_cf: cleanup event/counter validation
The validate_event() function just checked for reserved counters
in particular CPU-MF counter sets.  Because the number of counters
in counter sets vary among different hardware models, remove the
explicit check to tolerate new models.

Reserved counters are not accounted and, thus, will return zero.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-03-31 07:53:29 +02:00