Commit Graph

4196 Commits

Author SHA1 Message Date
Martin Schwidefsky
c7e8b2c21c s390: avoid cache aliasing under z/VM and KVM
commit 1f6b83e5e4 ("s390: avoid z13 cache aliasing") checks for the
machine type to optimize address space randomization and zero page
allocation to avoid cache aliases.

This check might fail under a hypervisor with migration support.
z/VMs "Single System Image and Live Guest Relocation" facility will
"fake" the machine type of the oldest system in the group. For example
in a group of zEC12 and Z13 the guest appears to run on a zEC12
(architecture fencing within the relocation domain)

Remove the machine type detection and always use cache aliasing
rules that are known to work for all machines. These are the z13
aliasing rules.

Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-16 12:04:18 +01:00
Sascha Silbe
f07f21b3e2 s390/sclp: _sclp_wait_int(): retain full PSW mask
There's no reason to clear all PSW mask bits other than the addressing
mode bits. Just use the previous PSW mask as-is.

Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-12 13:08:00 +01:00
Sebastian Ott
18e22a1772 s390: add support for ipl devices in subchannel sets > 0
Allow to ipl from CCW based devices residing in any subchannel set.

Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-11 13:56:27 +01:00
Sebastian Ott
e0bedada3a s390/ipl: fix out of bounds access in scpdata_write
The input buffer in reipl_fcp_scpdata_write is accessed out of bounds
when an offset is specified. The problem is that the offset refers to
the data we should write to and not to the buffer we read from.

So instead of
        memcpy(scp_data, buf + off, count);
we could just do
        memcpy(scp_data + off, buf, count);

However we not only modify the data but also store its length. For this to
work we'd need to remember a state per open FH. Since that's not possible
with sysfs callbacks let's just fail when an offset is specified.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-11 09:07:06 +01:00
Sebastian Ott
52d43d8184 s390/pci_dma: improve debugging of errors during dma map
Improve debugging to find out what went wrong during a failed
dma map/unmap operation.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-09 09:10:49 +01:00
Sebastian Ott
66728eeea6 s390/pci_dma: handle dma table failures
We use lazy allocation for translation table entries but don't handle
allocation (and other) failures during translation table updates.

Handle these failures and undo translation table updates when it's
meaningful.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-09 09:10:49 +01:00
Sebastian Ott
4d5a6b7295 s390/pci_dma: unify label of invalid translation table entries
Newly allocated translation table entries are flagged as invalid
and protected. If an existing translation table entry is invalidated,
the protection flag is left unchanged.

If a page (with invalid and protection flag set) is accessed it's
undefined which type of exception we'll receive.

Make sure to always set the invalid flag only.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-09 09:10:49 +01:00
Heiko Carstens
86b68c3873 s390/syscalls: remove system call number calculation
Explicitly write the system call number for each define instead of
calculating it. This makes it easier to parse the file when generating
system call tables for various tools and libraries.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-09 09:10:48 +01:00
Martin Schwidefsky
230ccb370f s390/diag: add a s390 prefix to the diagnose trace point
Documentation/trace/tracepoints.txt states that the naming scheme
for tracepoints is "subsys_event" to avoid collisions. Rename
the 'diagnose' tracepoint to 's390_diagnose'.

Reported-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-09 09:10:47 +01:00
Sascha Silbe
c6eafbf990 s390/head: fix error message on unsupported hardware
startup calls the C function _sclp_print_early() if the machine we're
running on is not supported by the kernel. sclp.c is getting built
with -m64, so _sclp_print_early() expects the zSeries ELF ABI to be
used.

We previously called _sclp_print_early() using the S/390 ELF ABI, with
a stack frame size of 96 bytes and while being in 31-bit address
mode. This caused _sclp_wait_int() (called indirectly from
_sclp_print_early()) to jump to an undefined address. While
_sclp_wait_int() contained some code to deal with being called in
31-bit addressing mode, it didn't quite work. While fixing this is
possible, the code would still only work by chance and could break any
time.

Ensure compliance with the zSeries ELF ABI by switching to 64-bit
addressing mode early and using a minimum stack frame size of 160
bytes.

Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-09 09:10:47 +01:00
Linus Torvalds
933425fb00 s390: A bunch of fixes and optimizations for interrupt and time
handling.
 
 PPC: Mostly bug fixes.
 
 ARM: No big features, but many small fixes and prerequisites including:
 - a number of fixes for the arch-timer
 - introducing proper level-triggered semantics for the arch-timers
 - a series of patches to synchronously halt a guest (prerequisite for
   IRQ forwarding)
 - some tracepoint improvements
 - a tweak for the EL2 panic handlers
 - some more VGIC cleanups getting rid of redundant state
 
 x86: quite a few changes:
 
 - support for VT-d posted interrupts (i.e. PCI devices can inject
 interrupts directly into vCPUs).  This introduces a new component (in
 virt/lib/) that connects VFIO and KVM together.  The same infrastructure
 will be used for ARM interrupt forwarding as well.
 
 - more Hyper-V features, though the main one Hyper-V synthetic interrupt
 controller will have to wait for 4.5.  These will let KVM expose Hyper-V
 devices.
 
 - nested virtualization now supports VPID (same as PCID but for vCPUs)
 which makes it quite a bit faster
 
 - for future hardware that supports NVDIMM, there is support for clflushopt,
 clwb, pcommit
 
 - support for "split irqchip", i.e. LAPIC in kernel + IOAPIC/PIC/PIT in
 userspace, which reduces the attack surface of the hypervisor
 
 - obligatory smattering of SMM fixes
 
 - on the guest side, stable scheduler clock support was rewritten to not
 require help from the hypervisor.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "First batch of KVM changes for 4.4.

  s390:
     A bunch of fixes and optimizations for interrupt and time handling.

  PPC:
     Mostly bug fixes.

  ARM:
     No big features, but many small fixes and prerequisites including:

      - a number of fixes for the arch-timer

      - introducing proper level-triggered semantics for the arch-timers

      - a series of patches to synchronously halt a guest (prerequisite
        for IRQ forwarding)

      - some tracepoint improvements

      - a tweak for the EL2 panic handlers

      - some more VGIC cleanups getting rid of redundant state

  x86:
     Quite a few changes:

      - support for VT-d posted interrupts (i.e. PCI devices can inject
        interrupts directly into vCPUs).  This introduces a new
        component (in virt/lib/) that connects VFIO and KVM together.
        The same infrastructure will be used for ARM interrupt
        forwarding as well.

      - more Hyper-V features, though the main one Hyper-V synthetic
        interrupt controller will have to wait for 4.5.  These will let
        KVM expose Hyper-V devices.

      - nested virtualization now supports VPID (same as PCID but for
        vCPUs) which makes it quite a bit faster

      - for future hardware that supports NVDIMM, there is support for
        clflushopt, clwb, pcommit

      - support for "split irqchip", i.e.  LAPIC in kernel +
        IOAPIC/PIC/PIT in userspace, which reduces the attack surface of
        the hypervisor

      - obligatory smattering of SMM fixes

      - on the guest side, stable scheduler clock support was rewritten
        to not require help from the hypervisor"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (123 commits)
  KVM: VMX: Fix commit which broke PML
  KVM: x86: obey KVM_X86_QUIRK_CD_NW_CLEARED in kvm_set_cr0()
  KVM: x86: allow RSM from 64-bit mode
  KVM: VMX: fix SMEP and SMAP without EPT
  KVM: x86: move kvm_set_irq_inatomic to legacy device assignment
  KVM: device assignment: remove pointless #ifdefs
  KVM: x86: merge kvm_arch_set_irq with kvm_set_msi_inatomic
  KVM: x86: zero apic_arb_prio on reset
  drivers/hv: share Hyper-V SynIC constants with userspace
  KVM: x86: handle SMBASE as physical address in RSM
  KVM: x86: add read_phys to x86_emulate_ops
  KVM: x86: removing unused variable
  KVM: don't pointlessly leave KVM_COMPAT=y in non-KVM configs
  KVM: arm/arm64: Merge vgic_set_lr() and vgic_sync_lr_elrsr()
  KVM: arm/arm64: Clean up vgic_retire_lr() and surroundings
  KVM: arm/arm64: Optimize away redundant LR tracking
  KVM: s390: use simple switch statement as multiplexer
  KVM: s390: drop useless newline in debugging data
  KVM: s390: SCA must not cross page boundaries
  KVM: arm: Do not indent the arguments of DECLARE_BITMAP
  ...
2015-11-05 16:26:26 -08:00
Linus Torvalds
39cf7c3981 IOMMU Updates for Linux v4.4
This time including:
 
 	* A new IOMMU driver for s390 pci devices
 
 	* Common dma-ops support based on iommu-api for ARM64. The plan is to
 	  use this as a basis for ARM32 and hopefully other architectures as
 	  well in the future.
 
 	* MSI support for ARM-SMMUv3
 
 	* Cleanups and dead code removal in the AMD IOMMU driver
 
 	* Better RMRR handling for the Intel VT-d driver
 
 	* Various other cleanups and small fixes
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Merge tag 'iommu-updates-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu updates from Joerg Roedel:
 "This time including:

   - A new IOMMU driver for s390 pci devices

   - Common dma-ops support based on iommu-api for ARM64.  The plan is
     to use this as a basis for ARM32 and hopefully other architectures
     as well in the future.

   - MSI support for ARM-SMMUv3

   - Cleanups and dead code removal in the AMD IOMMU driver

   - Better RMRR handling for the Intel VT-d driver

   - Various other cleanups and small fixes"

* tag 'iommu-updates-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (41 commits)
  iommu/vt-d: Fix return value check of parse_ioapics_under_ir()
  iommu/vt-d: Propagate error-value from ir_parse_ioapic_hpet_scope()
  iommu/vt-d: Adjust the return value of the parse_ioapics_under_ir
  iommu: Move default domain allocation to iommu_group_get_for_dev()
  iommu: Remove is_pci_dev() fall-back from iommu_group_get_for_dev
  iommu/arm-smmu: Switch to device_group call-back
  iommu/fsl: Convert to device_group call-back
  iommu: Add device_group call-back to x86 iommu drivers
  iommu: Add generic_device_group() function
  iommu: Export and rename iommu_group_get_for_pci_dev()
  iommu: Revive device_group iommu-ops call-back
  iommu/amd: Remove find_last_devid_on_pci()
  iommu/amd: Remove first/last_device handling
  iommu/amd: Initialize amd_iommu_last_bdf for DEV_ALL
  iommu/amd: Cleanup buffer allocation
  iommu/amd: Remove cmd_buf_size and evt_buf_size from struct amd_iommu
  iommu/amd: Align DTE flag definitions
  iommu/amd: Remove old alias handling code
  iommu/amd: Set alias DTE in do_attach/do_detach
  iommu/amd: WARN when __[attach|detach]_device are called with irqs enabled
  ...
2015-11-05 16:12:10 -08:00
Linus Torvalds
e627078a0c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "There is only one new feature in this pull for the 4.4 merge window,
  most of it is small enhancements, cleanup and bug fixes:

   - Add the s390 backend for the software dirty bit tracking.  This
     adds two new pgtable functions pte_clear_soft_dirty and
     pmd_clear_soft_dirty which is why there is a hit to
     arch/x86/include/asm/pgtable.h in this pull request.

   - A series of cleanup patches for the AP bus, this includes the
     removal of the support for two outdated crypto cards (PCICC and
     PCICA).

   - The irq handling / signaling on buffer full in the runtime
     instrumentation code is dropped.

   - Some micro optimizations: remove unnecessary memory barriers for a
     couple of functions: [smb_]rmb, [smb_]wmb, atomics, bitops, and for
     spin_unlock.  Use the builtin bswap if available and make
     test_and_set_bit_lock more cache friendly.

   - Statistics and a tracepoint for the diagnose calls to the
     hypervisor.

   - The CPU measurement facility support to sample KVM guests is
     improved.

   - The vector instructions are now always enabled for user space
     processes if the hardware has the vector facility.  This simplifies
     the FPU handling code.  The fpu-internal.h header is split into fpu
     internals, api and types just like x86.

   - Cleanup and improvements for the common I/O layer.

   - Rework udelay to solve a problem with kprobe.  udelay has busy loop
     semantics but still uses an idle processor state for the wait"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (66 commits)
  s390: remove runtime instrumentation interrupts
  s390/cio: de-duplicate subchannel validation
  s390/css: unneeded initialization in for_each_subchannel
  s390/Kconfig: use builtin bswap
  s390/dasd: fix disconnected device with valid path mask
  s390/dasd: fix invalid PAV assignment after suspend/resume
  s390/dasd: fix double free in dasd_eckd_read_conf
  s390/kernel: fix ptrace peek/poke for floating point registers
  s390/cio: move ccw_device_stlck functions
  s390/cio: move ccw_device_call_handler
  s390/topology: reduce per_cpu() invocations
  s390/nmi: reduce size of percpu variable
  s390/nmi: fix terminology
  s390/nmi: remove casts
  s390/nmi: remove pointless error strings
  s390: don't store registers on disabled wait anymore
  s390: get rid of __set_psw_mask()
  s390/fpu: split fpu-internal.h into fpu internals, api, and type headers
  s390/dasd: fix list_del corruption after lcu changes
  s390/spinlock: remove unneeded serializations at unlock
  ...
2015-11-04 11:31:31 -08:00
Linus Torvalds
b0f85fa11a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

Changes of note:

 1) Allow to schedule ICMP packets in IPVS, from Alex Gartrell.

 2) Provide FIB table ID in ipv4 route dumps just as ipv6 does, from
    David Ahern.

 3) Allow the user to ask for the statistics to be filtered out of
    ipv4/ipv6 address netlink dumps.  From Sowmini Varadhan.

 4) More work to pass the network namespace context around deep into
    various packet path APIs, starting with the netfilter hooks.  From
    Eric W Biederman.

 5) Add layer 2 TX/RX checksum offloading to qeth driver, from Thomas
    Richter.

 6) Use usec resolution for SYN/ACK RTTs in TCP, from Yuchung Cheng.

 7) Support Very High Throughput in wireless MESH code, from Bob
    Copeland.

 8) Allow setting the ageing_time in switchdev/rocker.  From Scott
    Feldman.

 9) Properly autoload L2TP type modules, from Stephen Hemminger.

10) Fix and enable offload features by default in 8139cp driver, from
    David Woodhouse.

11) Support both ipv4 and ipv6 sockets in a single vxlan device, from
    Jiri Benc.

12) Fix CWND limiting of thin streams in TCP, from Bendik Rønning
    Opstad.

13) Fix IPSEC flowcache overflows on large systems, from Steffen
    Klassert.

14) Convert bridging to track VLANs using rhashtable entries rather than
    a bitmap.  From Nikolay Aleksandrov.

15) Make TCP listener handling completely lockless, this is a major
    accomplishment.  Incoming request sockets now live in the
    established hash table just like any other socket too.

    From Eric Dumazet.

15) Provide more bridging attributes to netlink, from Nikolay
    Aleksandrov.

16) Use hash based algorithm for ipv4 multipath routing, this was very
    long overdue.  From Peter Nørlund.

17) Several y2038 cures, mostly avoiding timespec.  From Arnd Bergmann.

18) Allow non-root execution of EBPF programs, from Alexei Starovoitov.

19) Support SO_INCOMING_CPU as setsockopt, from Eric Dumazet.  This
    influences the port binding selection logic used by SO_REUSEPORT.

20) Add ipv6 support to VRF, from David Ahern.

21) Add support for Mellanox Spectrum switch ASIC, from Jiri Pirko.

22) Add rtl8xxxu Realtek wireless driver, from Jes Sorensen.

23) Implement RACK loss recovery in TCP, from Yuchung Cheng.

24) Support multipath routes in MPLS, from Roopa Prabhu.

25) Fix POLLOUT notification for listening sockets in AF_UNIX, from Eric
    Dumazet.

26) Add new QED Qlogic river, from Yuval Mintz, Manish Chopra, and
    Sudarsana Kalluru.

27) Don't fetch timestamps on AF_UNIX sockets, from Hannes Frederic
    Sowa.

28) Support ipv6 geneve tunnels, from John W Linville.

29) Add flood control support to switchdev layer, from Ido Schimmel.

30) Fix CHECKSUM_PARTIAL handling of potentially fragmented frames, from
    Hannes Frederic Sowa.

31) Support persistent maps and progs in bpf, from Daniel Borkmann.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1790 commits)
  sh_eth: use DMA barriers
  switchdev: respect SKIP_EOPNOTSUPP flag in case there is no recursion
  net: sched: kill dead code in sch_choke.c
  irda: Delete an unnecessary check before the function call "irlmp_unregister_service"
  net: dsa: mv88e6xxx: include DSA ports in VLANs
  net: dsa: mv88e6xxx: disable SA learning for DSA and CPU ports
  net/core: fix for_each_netdev_feature
  vlan: Invoke driver vlan hooks only if device is present
  arcnet/com20020: add LEDS_CLASS dependency
  bpf, verifier: annotate verbose printer with __printf
  dp83640: Only wait for timestamps for packets with timestamping enabled.
  ptp: Change ptp_class to a proper bitmask
  dp83640: Prune rx timestamp list before reading from it
  dp83640: Delay scheduled work.
  dp83640: Include hash in timestamp/packet matching
  ipv6: fix tunnel error handling
  net/mlx5e: Fix LSO vlan insertion
  net/mlx5e: Re-eanble client vlan TX acceleration
  net/mlx5e: Return error in case mlx5e_set_features() fails
  net/mlx5e: Don't allow more than max supported channels
  ...
2015-11-04 09:41:05 -08:00
Linus Torvalds
ccc9d4a6d6 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "API:

   - Add support for cipher output IVs in testmgr
   - Add missing crypto_ahash_blocksize helper
   - Mark authenc and des ciphers as not allowed under FIPS.

Algorithms:

   - Add CRC support to 842 compression
   - Add keywrap algorithm
   - A number of changes to the akcipher interface:
      + Separate functions for setting public/private keys.
      + Use SG lists.

Drivers:

   - Add Intel SHA Extension optimised SHA1 and SHA256
   - Use dma_map_sg instead of custom functions in crypto drivers
   - Add support for STM32 RNG
   - Add support for ST RNG
   - Add Device Tree support to exynos RNG driver
   - Add support for mxs-dcp crypto device on MX6SL
   - Add xts(aes) support to caam
   - Add ctr(aes) and xts(aes) support to qat
   - A large set of fixes from Russell King for the marvell/cesa driver"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (115 commits)
  crypto: asymmetric_keys - Fix unaligned access in x509_get_sig_params()
  crypto: akcipher - Don't #include crypto/public_key.h as the contents aren't used
  hwrng: exynos - Add Device Tree support
  hwrng: exynos - Fix missing configuration after suspend to RAM
  hwrng: exynos - Add timeout for waiting on init done
  dt-bindings: rng: Describe Exynos4 PRNG bindings
  crypto: marvell/cesa - use __le32 for hardware descriptors
  crypto: marvell/cesa - fix missing cpu_to_le32() in mv_cesa_dma_add_op()
  crypto: marvell/cesa - use memcpy_fromio()/memcpy_toio()
  crypto: marvell/cesa - use gfp_t for gfp flags
  crypto: marvell/cesa - use dma_addr_t for cur_dma
  crypto: marvell/cesa - use readl_relaxed()/writel_relaxed()
  crypto: caam - fix indentation of close braces
  crypto: caam - only export the state we really need to export
  crypto: caam - fix non-block aligned hash calculation
  crypto: caam - avoid needlessly saving and restoring caam_hash_ctx
  crypto: caam - print errno code when hash registration fails
  crypto: marvell/cesa - fix memory leak
  crypto: marvell/cesa - fix first-fragment handling in mv_cesa_ahash_dma_last_req()
  crypto: marvell/cesa - rearrange handling for sw padded hashes
  ...
2015-11-04 09:11:12 -08:00
Paolo Bonzini
197a4f4b06 KVM/ARM Changes for v4.4-rc1
Includes a number of fixes for the arch-timer, introducing proper
 level-triggered semantics for the arch-timers, a series of patches to
 synchronously halt a guest (prerequisite for IRQ forwarding), some tracepoint
 improvements, a tweak for the EL2 panic handlers, some more VGIC cleanups
 getting rid of redundant state, and finally a stylistic change that gets rid of
 some ctags warnings.
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Merge tag 'kvm-arm-for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM Changes for v4.4-rc1

Includes a number of fixes for the arch-timer, introducing proper
level-triggered semantics for the arch-timers, a series of patches to
synchronously halt a guest (prerequisite for IRQ forwarding), some tracepoint
improvements, a tweak for the EL2 panic handlers, some more VGIC cleanups
getting rid of redundant state, and finally a stylistic change that gets rid of
some ctags warnings.

Conflicts:
	arch/x86/include/asm/kvm_host.h
2015-11-04 16:24:17 +01:00
Martin Schwidefsky
b38feccd66 s390: remove runtime instrumentation interrupts
The external interrupts for runtime instrumentation buffer-full
and runtime instrumentation halted are unused and have no current
user. Remove the support and ignore the second parameter of the
s390_runtime_instr system call from now on.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-03 14:40:51 +01:00
Christian Borntraeger
295d8fa961 s390/Kconfig: use builtin bswap
Depending on the gcc version we can use builtin_bswap instead of
architecture functions. Doing so is better than the inline assembly
version of load reverse for two reasons:
- the sequence of load reversed, apply constant mask, save reversed can
  be optimized to load, apply reversed mask, save
- builtins are slightly better to optimize e.g. gcc instruction
  scheduler cannot optimize grouping on inline assemblies.

To enable set we have to ARCH_USE_BUILTIN_BSWAP.
bloat-o-meter results:
add/remove: 1/1 grow/shrink: 75/533 up/down: 1711/-9394 (-7683)

Suggested-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-03 14:40:48 +01:00
Martin Schwidefsky
55a423b6f1 s390/kernel: fix ptrace peek/poke for floating point registers
git commit 155e839a81
"s390/kernel: dynamically allocate FP register save area"
introduced a regression in regard to ptrace.

If the vector register extension is not present or unused the
ptrace peek of a floating pointer register return incorrect data
and the ptrace poke to a floating pointer register overwrites the
task structure starting at task->thread.fpu.fprs.

Cc: stable@kernel.org # v4.3
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-03 14:40:42 +01:00
Joerg Roedel
b67ad2f7c7 Merge branches 'x86/vt-d', 'arm/omap', 'arm/smmu', 's390', 'core' and 'x86/amd' into next
Conflicts:
	drivers/iommu/amd_iommu_types.h
2015-11-02 20:03:34 +09:00
Christian Borntraeger
46b708ea87 KVM: s390: use simple switch statement as multiplexer
We currently do some magic shifting (by exploiting that exit codes
are always a multiple of 4) and a table lookup to jump into the
exit handlers. This causes some calculations and checks, just to
do an potentially expensive function call.

Changing that to a switch statement gives the compiler the chance
to inline and dynamically decide between jump tables or inline
compare and branches. In addition it makes the code more readable.

bloat-o-meter gives me a small reduction in code size:

add/remove: 0/7 grow/shrink: 1/1 up/down: 986/-1334 (-348)
function                                     old     new   delta
kvm_handle_sie_intercept                      72    1058    +986
handle_prog                                  704     696      -8
handle_noop                                   54       -     -54
handle_partial_execution                      60       -     -60
intercept_funcs                              120       -    -120
handle_instruction                           198       -    -198
handle_validity                              210       -    -210
handle_stop                                  316       -    -316
handle_external_interrupt                    368       -    -368

Right now my gcc does conditional branches instead of jump tables.
The inlining seems to give us enough cycles as some micro-benchmarking
shows minimal improvements, but still in noise.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-10-29 15:59:11 +01:00
Christian Borntraeger
58c383c62e KVM: s390: drop useless newline in debugging data
the s390 debug feature does not need newlines. In fact it will
result in empty lines. Get rid of 4 leftovers.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-10-29 15:58:54 +01:00
David Hildenbrand
c5c2c39346 KVM: s390: SCA must not cross page boundaries
We seemed to have missed a few corner cases in commit f6c137ff00
("KVM: s390: randomize sca address").

The SCA has a maximum size of 2112 bytes. By setting the sca_offset to
some unlucky numbers, we exceed the page.

0x7c0 (1984) -> Fits exactly
0x7d0 (2000) -> 16 bytes out
0x7e0 (2016) -> 32 bytes out
0x7f0 (2032) -> 48 bytes out

One VCPU entry is 32 bytes long.

For the last two cases, we actually write data to the other page.
1. The address of the VCPU.
2. Injection/delivery/clearing of SIGP externall calls via SIGP IF.

Especially the 2. happens regularly. So this could produce two problems:
1. The guest losing/getting external calls.
2. Random memory overwrites in the host.

So this problem happens on every 127 + 128 created VM with 64 VCPUs.

Cc: stable@vger.kernel.org # v3.15+
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-10-29 15:58:41 +01:00
Heiko Carstens
439eb131f7 s390/topology: reduce per_cpu() invocations
Each per_cpu() invocation generates extra code. Since there are a lot
of similiar calls in the topology code we can avoid a lot of them.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:34:39 +01:00
Heiko Carstens
36324963a3 s390/nmi: reduce size of percpu variable
Change the flag fields within struct mcck_struct to simple bit fields
to reduce the size of the structure which is used as percpu variable.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:33:57 +01:00
Heiko Carstens
975be635d9 s390/nmi: fix terminology
According to the architecture registers are validated and not
revalidated. So change comments and functions names to match.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:33:56 +01:00
Heiko Carstens
dc6e15556a s390/nmi: remove casts
Remove all the casts to and from the machine check interruption code.
This patch changes struct mci to a union, which contains an anonymous
structure with the already known bits and in addition an unsigned
long field, which contains the raw machine check interruption code.

This allows to simply assign and decoce the interruption code value
without the need for all those casts we had all the time.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:33:55 +01:00
Heiko Carstens
3d68286a43 s390/nmi: remove pointless error strings
s390_handle_damage() has character string parameter which was used as
a pointer to verbose error message. The hope was (a lot of years ago)
when analyzing dumps that register R2 would still contain the pointer
and therefore it would be rather easy to tell what went wrong.

However gcc optimizes the strings away since a long time. And even if
it wouldn't it is necessary to have a close look at the machine check
interruption code to tell what's wrong.

So remove the pointless error strings.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:33:54 +01:00
Heiko Carstens
f9e6edfb9c s390: don't store registers on disabled wait anymore
The current disabled wait code stores register contents into their
save areas, however it is (at least) missing the new vector registers.

Given the fact that the whole exercise seems to be rather pointless
simply don't save any registers anymore.

In a "live" system it is always possible to inspect register contents,
and in case of a dump the register contents will be stored by the
dump mechanism.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:33:48 +01:00
Heiko Carstens
ecbafda853 s390: get rid of __set_psw_mask()
With the removal of 31 bit code we can always assume that the epsw
instruction is available. Therefore use the __extract_psw() function
to disable and enable machine checks.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27 09:33:44 +01:00
Christoffer Dall
3217f7c25b KVM: Add kvm_arch_vcpu_{un}blocking callbacks
Some times it is useful for architecture implementations of KVM to know
when the VCPU thread is about to block or when it comes back from
blocking (arm/arm64 needs to know this to properly implement timers, for
example).

Therefore provide a generic architecture callback function in line with
what we do elsewhere for KVM generic-arch interactions.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-22 23:01:41 +02:00
David S. Miller
26440c835f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/usb/asix_common.c
	net/ipv4/inet_connection_sock.c
	net/switchdev/switchdev.c

In the inet_connection_sock.c case the request socket hashing scheme
is completely different in net-next.

The other two conflicts were overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-20 06:08:27 -07:00
Hendrik Brueckner
b0753902d4 s390/fpu: split fpu-internal.h into fpu internals, api, and type headers
Split the API and FPU type definitions into separate header files
similar to "x86/fpu: Rename fpu-internal.h to fpu/internal.h" (78f7f1e54b).

The new header files and their meaning are:

asm/fpu/types.h:
	FPU related data types, needed for 'struct thread_struct' and
	'struct task_struct'.

asm/fpu/api.h:
	FPU related 'public' functions for other subsystems and device
	drivers.

asm/fpu/internal.h:
	FPU internal functions mainly used to convert
	FPU register contents in signal handling.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-16 09:41:12 +02:00
LABBE Corentin
19b14e7e22 crypto: s390/sha - replace raw value by their coresponding define
SHA_MAX_STATE_SIZE is just the number of u32 word for SHA512.
So replace the raw value "16" by their meaning (SHA512_DIGEST_SIZE / 4)

Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-10-15 21:05:11 +08:00
Christian Borntraeger
fdbbe8e791 s390/spinlock: remove unneeded serializations at unlock
the kernel locks have aqcuire/release semantics. No operation done
after the lock can be "moved" before the lock and no operation before
the unlock can be moved after the unlock. But it is perfectly fine
that memory accesses which happen code wise after unlock are performed
within the critical section.
On s390x, reads are in-order with other reads (PoP section
"Storage-Operand Fetch References") and writes are in-order with
other writes (PoP section "Storage-Operand Store References"). Writes
are also in-order with reads to the same memory location (PoP section
"Storage-Operand Store References"). To other CPUs (and the channel
subsystem), reads additionally appear to be performed prior to reads or
writes that happen after them in the conceptual sequence (PoP section
"Relation between Operand Accesses").
So at least as observed by other CPUs and the channel subsystem, reads
inside the critical sections will not happen after unlock (and writes
are in-order anyway). That's exactly what we need for "RELEASE
operations" (memory-barriers.txt): "It guarantees that all memory
operations before the RELEASE operation will appear to happen before the
RELEASE operation with respect to the other components of the system."

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-By: Sascha Silbe <silbe@linux.vnet.ibm.com>
[cross-reading and lot of improvements for the patch description]
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:25 +02:00
Heiko Carstens
29b0a8250b s390/etr,stp: fix possible deadlock on machine check
The first level machine check handler for etr and stp machine checks may
call queue_work() while in nmi context. This may deadlock e.g. if the
machine check happened when the interrupted context did hold a lock, that
also will be acquired by queue_work().
Therefore split etr and stp machine check handling into first and second
level handling. The second level handling will then issue the queue_work()
call in process context which avoids the potential deadlock.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:18 +02:00
Sebastian Ott
7cc8944e13 s390/pci: reshuffle struct used to write debug data
zpci_err_insn writes stale stack content to the debugfs.

Ensure that the struct in zpci_err_insn is ordered in a way that
we don't have uninitialized holes in it. In addition to that
add the packed attribute.

Fixes: 3d8258e (s390/pci: move debug messages to debugfs)
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:17 +02:00
Heiko Carstens
48002bd5af s390/bitops: remove 31 bit related comments
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:15 +02:00
Heiko Carstens
e4165dcbc0 s390/cmpxchg: remove dead code
With the removal of 31 bit support a couple of defines became unused.
Remove them.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:15 +02:00
Heiko Carstens
004f0bba19 s390/nmi: change type of mcck_interruption_code lowcore field
For some unknown reason the mcck_interruption_code field is defined
as array of two 32 bit values. Given that this actually is a 64 bit
field according to the architecture, change the type to u64.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:15 +02:00
Heiko Carstens
92778b9920 s390/flags: use _BITUL macro
The defines that are used in entry.S have been partially converted to
use the _BITUL macro (setup.h). This patch converts the rest.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:14 +02:00
Heiko Carstens
ac25e790d9 s390/flags: fix flag handling
The cpu flags and pt_regs flags fields are each 64 bits in size. A flag can
be set with helper functions like set_cpu_flags().

These functions create a mask using "1U << flag". This doesn't work if flag
is larger than 31, since 1U << 32 == 0.

So fix this in case we ever will have such flag numbers.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:14 +02:00
Heiko Carstens
db7e007fd6 s390/udelay: make udelay have busy loop semantics
When using systemtap it was observed that our udelay implementation is
rather suboptimal if being called from a kprobe handler installed by
systemtap.

The problem observed when a kprobe was installed on lock_acquired().
When the probe was hit the kprobe handler did call udelay, which set
up an (internal) timer and reenabled interrupts (only the clock comparator
interrupt) and waited for the interrupt.
This is an optimization to avoid that the cpu is busy looping while waiting
that enough time passes. The problem is that the interrupt handler still
does call irq_enter()/irq_exit() which then again can lead to a deadlock,
since some accounting functions may take locks as well.

If one of these locks is the same, which caused lock_acquired() to be
called, we have a nice deadlock.

This patch reworks the udelay code for the interrupts disabled case to
immediately leave the low level interrupt handler when the clock
comparator interrupt happens. That way no C code is being called and the
deadlock cannot happen anymore.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:13 +02:00
Christian Borntraeger
e22cf8ca6f s390/cpumf: rework program parameter setting to detect guest samples
The program parameter can be used to mark hardware samples with
some token.  Previously, it was used to mark guest samples only.

Improve the program parameter doubleword by combining two parts,
the leftmost LPP part and the rightmost PID part.  Set the PID
part for processes by using the task PID.
To distinguish host and guest samples for the kernel (PID part
is zero), the guest must always set the program paramater to a
non-zero value.  Use the leftmost bit in the LPP part of the
program parameter to be able to detect guest kernel samples.

[brueckner@linux.vnet.ibm.com]: Split __LC_CURRENT and introduced
__LC_LPP. Corrected __LC_CURRENT users and adjusted assembler parts.
And updated the commit message accordingly.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:12 +02:00
Martin Schwidefsky
6a62b485ea s390/asm: make use of the OFFSET macro to define assember constants
The use of OFFSET instead of DEFINE makes the definitions in asm-offsets.c
more readable. While we are at it sort the defines for struct _lowcore
according to the field order and remove some unneeded defines.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:10 +02:00
Hendrik Brueckner
83abeffbd5 s390/entry: add assembler macro to conveniently tests under mask
Various functions in entry.S perform test-under-mask instructions
to test for particular bits in memory.  Because test-under-mask uses
a mask value of one byte, the mask value and the offset into the
memory must be calculated manually.  This easily introduces errors
and is hard to review and read.

Introduce the TSTMSK assembler macro to specify a mask constant and
let the macro calculate the offset and the byte mask to generate a
test-under-mask instruction.  The benefit is that existing symbolic
constants can now be used for tests.  Also the macro checks for
zero mask values and mask values that consist of multiple bytes.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:09 +02:00
Hendrik Brueckner
0ac277790e s390/fpu: add static FPU save area for init_task
Previously, the init task did not have an allocated FPU save area and
saving an FPU state was not possible.  Now if the vector extension is
always enabled, provide a static FPU save area to save FPU states of
vector instructions that can be executed quite early.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:08 +02:00
Hendrik Brueckner
b5510d9b68 s390/fpu: always enable the vector facility if it is available
If the kernel detects that the s390 hardware supports the vector
facility, it is enabled by default at an early stage.  To force
it off, use the novx kernel parameter.  Note that there is a small
time window, where the vector facility is enabled before it is
forced to be off.

With enabling the vector facility by default, the FPU save and
restore functions can be improved.  They do not longer require
to manage expensive control register updates to enable or disable
the vector enablement control for particular processes.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:08 +02:00
Martin Schwidefsky
395e6aa1d0 s390/mm: try to avoid storage key operation in ptep_set_access_flags
The call to pgste_set_key in ptep_set_access_flags can be avoided
if the old pte is found to be valid at the time the new access
rights are set. The function that created the old, valid pte already
completed the required storage key operation.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:07 +02:00
Martin Schwidefsky
5da7667c03 s390/barrier: remove unnecessary serialization in atomics and bitops
The principles of operation states reads are in order, writes are in
order, writes can be reordered after reads, but no reads can be
reordered after writes.

The atomic and bitops variantes for z196 use the interlocked-access
facility instructions with a memory barrier before and after the
instruction. Because of the memory ordering the first barrier is
unnecessary and can be removed.

Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:07 +02:00