Commit Graph

54 Commits

Author SHA1 Message Date
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Heiko Carstens
58cdf5eb13 KVM: s390: use new mm defines instead of magic values
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-07-26 08:25:10 +02:00
Linus Torvalds
c136b84393 PPC:
- Better machine check handling for HV KVM
 - Ability to support guests with threads=2, 4 or 8 on POWER9
 - Fix for a race that could cause delayed recognition of signals
 - Fix for a bug where POWER9 guests could sleep with interrupts pending.
 
 ARM:
 - VCPU request overhaul
 - allow timer and PMU to have their interrupt number selected from userspace
 - workaround for Cavium erratum 30115
 - handling of memory poisonning
 - the usual crop of fixes and cleanups
 
 s390:
 - initial machine check forwarding
 - migration support for the CMMA page hinting information
 - cleanups and fixes
 
 x86:
 - nested VMX bugfixes and improvements
 - more reliable NMI window detection on AMD
 - APIC timer optimizations
 
 Generic:
 - VCPU request overhaul + documentation of common code patterns
 - kvm_stat improvements
 
 There is a small conflict in arch/s390 due to an arch-wide field rename.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "PPC:
   - Better machine check handling for HV KVM
   - Ability to support guests with threads=2, 4 or 8 on POWER9
   - Fix for a race that could cause delayed recognition of signals
   - Fix for a bug where POWER9 guests could sleep with interrupts pending.

  ARM:
   - VCPU request overhaul
   - allow timer and PMU to have their interrupt number selected from userspace
   - workaround for Cavium erratum 30115
   - handling of memory poisonning
   - the usual crop of fixes and cleanups

  s390:
   - initial machine check forwarding
   - migration support for the CMMA page hinting information
   - cleanups and fixes

  x86:
   - nested VMX bugfixes and improvements
   - more reliable NMI window detection on AMD
   - APIC timer optimizations

  Generic:
   - VCPU request overhaul + documentation of common code patterns
   - kvm_stat improvements"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (124 commits)
  Update my email address
  kvm: vmx: allow host to access guest MSR_IA32_BNDCFGS
  x86: kvm: mmu: use ept a/d in vmcs02 iff used in vmcs12
  kvm: x86: mmu: allow A/D bits to be disabled in an mmu
  x86: kvm: mmu: make spte mmio mask more explicit
  x86: kvm: mmu: dead code thanks to access tracking
  KVM: PPC: Book3S: Fix typo in XICS-on-XIVE state saving code
  KVM: PPC: Book3S HV: Close race with testing for signals on guest entry
  KVM: PPC: Book3S HV: Simplify dynamic micro-threading code
  KVM: x86: remove ignored type attribute
  KVM: LAPIC: Fix lapic timer injection delay
  KVM: lapic: reorganize restart_apic_timer
  KVM: lapic: reorganize start_hv_timer
  kvm: nVMX: Check memory operand to INVVPID
  KVM: s390: Inject machine check into the nested guest
  KVM: s390: Inject machine check into the guest
  tools/kvm_stat: add new interactive command 'b'
  tools/kvm_stat: add new command line switch '-i'
  tools/kvm_stat: fix error on interactive command 'g'
  KVM: SVM: suppress unnecessary NMI singlestep on GIF=0 and nested exit
  ...
2017-07-06 18:38:31 -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
Heiko Carstens
addb63c18a KVM: s390: gaccess: fix real-space designation asce handling for gmap shadows
For real-space designation asces the asce origin part is only a token.
The asce token origin must not be used to generate an effective
address for storage references. This however is erroneously done
within kvm_s390_shadow_tables().

Furthermore within the same function the wrong parts of virtual
addresses are used to generate a corresponding real address
(e.g. the region second index is used as region first index).

Both of the above can result in incorrect address translations. Only
for real space designations with a token origin of zero and addresses
below one megabyte the translation was correct.

Furthermore replace a "!asce.r" statement with a "!*fake" statement to
make it more obvious that a specific condition has nothing to do with
the architecture, but with the fake handling of real space designations.

Fixes: 3218f7094b ("s390/mm: support real-space for gmap shadows")
Cc: David Hildenbrand <david@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-06-22 12:53:34 +02:00
Martin Schwidefsky
1cae025577 KVM: s390: avoid packed attribute
For naturally aligned and sized data structures avoid superfluous
packed and aligned attributes.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-06-22 12:41:07 +02:00
Christian Borntraeger
6ae1574c2a KVM: s390: implement instruction execution protection for emulated
ifetch

While currently only used to fetch the original instruction on failure
for getting the instruction length code, we should make the page table
walking code future proof.

Suggested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-06-22 12:41:06 +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
Linus Torvalds
2d3e4866de * ARM: HYP mode stub supports kexec/kdump on 32-bit; improved PMU
support; virtual interrupt controller performance improvements; support
 for userspace virtual interrupt controller (slower, but necessary for
 KVM on the weird Broadcom SoCs used by the Raspberry Pi 3)
 
 * MIPS: basic support for hardware virtualization (ImgTec
 P5600/P6600/I6400 and Cavium Octeon III)
 
 * PPC: in-kernel acceleration for VFIO
 
 * s390: support for guests without storage keys; adapter interruption
 suppression
 
 * x86: usual range of nVMX improvements, notably nested EPT support for
 accessed and dirty bits; emulation of CPL3 CPUID faulting
 
 * generic: first part of VCPU thread request API; kvm_stat improvements
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "ARM:
   - HYP mode stub supports kexec/kdump on 32-bit
   - improved PMU support
   - virtual interrupt controller performance improvements
   - support for userspace virtual interrupt controller (slower, but
     necessary for KVM on the weird Broadcom SoCs used by the Raspberry
     Pi 3)

  MIPS:
   - basic support for hardware virtualization (ImgTec P5600/P6600/I6400
     and Cavium Octeon III)

  PPC:
   - in-kernel acceleration for VFIO

  s390:
   - support for guests without storage keys
   - adapter interruption suppression

  x86:
   - usual range of nVMX improvements, notably nested EPT support for
     accessed and dirty bits
   - emulation of CPL3 CPUID faulting

  generic:
   - first part of VCPU thread request API
   - kvm_stat improvements"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits)
  kvm: nVMX: Don't validate disabled secondary controls
  KVM: put back #ifndef CONFIG_S390 around kvm_vcpu_kick
  Revert "KVM: Support vCPU-based gfn->hva cache"
  tools/kvm: fix top level makefile
  KVM: x86: don't hold kvm->lock in KVM_SET_GSI_ROUTING
  KVM: Documentation: remove VM mmap documentation
  kvm: nVMX: Remove superfluous VMX instruction fault checks
  KVM: x86: fix emulation of RSM and IRET instructions
  KVM: mark requests that need synchronization
  KVM: return if kvm_vcpu_wake_up() did wake up the VCPU
  KVM: add explicit barrier to kvm_vcpu_kick
  KVM: perform a wake_up in kvm_make_all_cpus_request
  KVM: mark requests that do not need a wakeup
  KVM: remove #ifndef CONFIG_S390 around kvm_vcpu_wake_up
  KVM: x86: always use kvm_make_request instead of set_bit
  KVM: add kvm_{test,clear}_request to replace {test,clear}_bit
  s390: kvm: Cpu model support for msa6, msa7 and msa8
  KVM: x86: remove irq disablement around KVM_SET_CLOCK/KVM_GET_CLOCK
  kvm: better MWAIT emulation for guests
  KVM: x86: virtualize cpuid faulting
  ...
2017-05-08 12:37:56 -07:00
Heiko Carstens
232b8e3b1d KVM: s390: remove change-recording override support
Change-recording override (CO) was never implemented in any
machine. According to the architecture it is unpredictable if a
translation-specification exception will be recognized if the bit is
set and EDAT1 does not apply.
Therefore the easiest solution is to simply ignore the bit.

This also fixes commit cd1836f583 ("KVM: s390:
instruction-execution-protection support"). A guest may enable
instruction-execution-protection (IEP) but not EDAT1. In such a case
the guest_translate() function (arch/s390/kvm/gaccess.c) will report a
specification exception on pages that have the IEP bit set while it
should not.

It might make sense to add full IEP support to guest_translate() and
the GACC_IFETCH case. However, as far as I can tell the GACC_IFETCH
case is currently only used after an instruction was executed in order
to fetch the failing instruction. So there is no additional problem
*currently*.

Fixes: cd1836f583 ("KVM: s390: instruction-execution-protection support")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-04-03 12:45:08 +02:00
David Hildenbrand
0c9d86833d KVM: s390: use defines for execution controls
Let's replace the bitmasks by defines. Reconstructed from code, comments
and commit messages.

Tried to keep the defines short and map them to feature names. In case
they don't completely map to features, keep them in the stye of ICTL
defines.

This effectively drops all "U" from the existing numbers. I think this
should be fine (as similarly done for e.g. ICTL defines).

I am not 100% sure about the ECA_MVPGI and ECA_PROTEXCI bits as they are
always used in pairs.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170313104828.13362-1-david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
[some renames, add one missing place]
2017-03-16 13:05:10 +01:00
Ingo Molnar
589ee62844 sched/headers: Prepare to remove the <linux/mm_types.h> dependency from <linux/sched.h>
Update code that relied on sched.h including various MM types for them.

This will allow us to remove the <linux/mm_types.h> include from <linux/sched.h>.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:37 +01:00
Christian Borntraeger
27f67f8727 KVM: s390: Get rid of ar_t
sparse with __CHECK_ENDIAN__ shows that ar_t was never properly
used across KVM on s390. We can now:
- fix all places
- do not make ar_t special
Since ar_t is just used as a register number (no endianness issues
for u8), and all other register numbers are also just plain int
variables, let's just use u8, which matches the __u8 in the userspace
ABI for the memop ioctl.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-01-30 11:17:29 +01:00
Christian Borntraeger
a679c547d1 KVM: s390: gaccess: add ESOP2 handling
When we access guest memory and run into a protection exception, we
need to pass the exception data to the guest. ESOP2 provides detailed
information about all protection exceptions which ESOP1 only partially
provided.

The gaccess changes make sure, that the guest always gets all
available information.

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-01-30 11:17:27 +01:00
Janosch Frank
c14b88d766 KVM: s390: gaccess: simplify translation exception handling
The payload data for protection exceptions is a superset of the
payload of other translation exceptions. Let's set the additional
flags and use a fall through to minimize code duplication.

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 09:07:53 +02:00
David Hildenbrand
3218f7094b s390/mm: support real-space for gmap shadows
We can easily support real-space designation just like EDAT1 and EDAT2.
So guest2 can provide for guest3 an asce with the real-space control being
set.

We simply have to allocate the biggest page table possible and fake all
levels.

There is no protection to consider. If we exceed guest memory, vsie code
will inject an addressing exception (via program intercept). In the future,
we could limit the fake table level to the gmap page table.

As the top level page table can never go away, such gmap shadows will never
get unshadowed, we'll have to come up with another way to limit the number
of kept gmap shadows.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:55:02 +02:00
David Hildenbrand
1c65781b56 s390/mm: push rte protection down to shadow pte
Just like we already do with ste protection, let's take rte protection
into account. This way, the host pte doesn't have to be mapped writable.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:55:00 +02:00
David Hildenbrand
18b8980988 s390/mm: support EDAT2 for gmap shadows
If the guest is enabled for EDAT2, we can easily create shadows for
guest2 -> guest3 provided tables that make use of EDAT2.

If guest2 references a 2GB page, this memory looks consecutive for guest2,
but it does not have to be so for us. Therefore we have to create fake
segment and page tables.

This works just like EDAT1 support, so page tables are removed when the
parent table (r3t table entry) is changed.

We don't hve to care about:
- ACCF-Validity Control in RTTE
- Access-Control Bits in RTTE
- Fetch-Protection Bit in RTTE
- Common-Region Bit in RTTE

Just like for EDAT1, all bits might be dropped and there is no guaranteed
that they are active.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:56 +02:00
David Hildenbrand
fd8d4e3ab6 s390/mm: support EDAT1 for gmap shadows
If the guest is enabled for EDAT1, we can easily create shadows for
guest2 -> guest3 provided tables that make use of EDAT1.

If guest2 references a 1MB page, this memory looks consecutive for guest2,
but it might not be so for us. Therefore we have to create fake page tables.

We can easily add that to our existing infrastructure. The invalidation
mechanism will make sure that fake page tables are removed when the parent
table (sgt table entry) is changed.

As EDAT1 also introduced protection on all page table levels, we have to
also shadow these correctly.

We don't have to care about:
- ACCF-Validity Control in STE
- Access-Control Bits in STE
- Fetch-Protection Bit in STE
- Common-Segment Bit in STE

As all bits might be dropped and there is no guaranteed that they are
active ("unpredictable whether the CPU uses these bits", "may be used").
Without using EDAT1 in the shadow ourselfes (STE-format control == 0),
simply shadowing these bits would not be enough. They would be ignored.

Please note that we are using the "fake" flag to make this look consistent
with further changes (EDAT2, real-space designation support) and don't let
the shadow functions handle fc=1 stes.

In the future, with huge pages in the host, gmap_shadow_pgt() could simply
try to map a huge host page if "fake" is set to one and indicate via return
value that no lower fake tables / shadow ptes are required.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:51 +02:00
David Hildenbrand
00fc062d53 s390/mm: push ste protection down to shadow pte
If a guest ste is read-only, it doesn't make sense to force the ptes in as
writable in the host. If the source page is read-only in the host, it won't
have to be made writable. Please note that if the source page is not
available, it will still be faulted in writable. This can be changed
internally later on.

If ste protection is removed, underlying shadow tables are also removed,
therefore this change does not affect the guest.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:45 +02:00
David Hildenbrand
f4debb4090 s390/mm: take ipte_lock during shadow faults
Let's take the ipte_lock while working on guest 2 provided page table, just
like the other gaccess functions.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:40 +02:00
David Hildenbrand
7a6741576b s390/mm: protection exceptions are corrrectly shadowed
As gmap shadows contains correct protection permissions, protection
exceptons can directly be forwarded to guest 3. If we would encounter
a protection exception while faulting, the next guest 3 run will
automatically handle that for us.

Keep the dat_protection logic in place, as it will be helpful later.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:34 +02:00
David Hildenbrand
e52f8b6112 s390/mm: take the mmap_sem in kvm_s390_shadow_fault()
Instead of doing it in the caller, let's just take the mmap_sem
in kvm_s390_shadow_fault(). By taking it as read, we allow parallel
faulting on shadow page tables, gmap shadow code is prepared for that.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:33 +02:00
David Hildenbrand
a9d23e71d7 s390/mm: shadow pages with real guest requested protection
We really want to avoid manually handling protection for nested
virtualization. By shadowing pages with the protection the guest asked us
for, the SIE can handle most protection-related actions for us (e.g.
special handling for MVPG) and we can directly forward protection
exceptions to the guest.

PTEs will now always be shadowed with the correct _PAGE_PROTECT flag.
Unshadowing will take care of any guest changes to the parent PTE and
any host changes to the host PTE. If the host PTE doesn't have the
fitting access rights or is not available, we have to fix it up.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:19 +02:00
Martin Schwidefsky
aa17aa57cf s390/mm: add kvm shadow fault function
This patch introduces function kvm_s390_shadow_fault() used to resolve a
fault on a shadow gmap. This function will do validity checking and
build up the shadow page table hierarchy in order to fault in the
requested page into the shadow page table structure.

If an exception occurs while shadowing, guest 2 has to be notified about
it using either an exception or a program interrupt intercept. If
concurrent unshadowing occurres, this function will simply return with
-EAGAIN and the caller has to retry.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:12 +02:00
David Hildenbrand
bcfa01d787 KVM: s390: gaccess: convert get_vcpu_asce()
Let's use our new function for preparing translation exceptions.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:16 +02:00
David Hildenbrand
cde0dcfb5d KVM: s390: gaccess: convert guest_page_range()
Let's use our new function for preparing translation exceptions. As we will
need the correct ar, let's pass that to guest_page_range().

This will also make sure that the guest address is stored in the tec
for applicable excptions.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:15 +02:00
David Hildenbrand
fbcb7d5157 KVM: s390: gaccess: convert guest_translate_address()
Let's use our new function for preparing translation exceptions.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:15 +02:00
David Hildenbrand
3e3c67f6a3 KVM: s390: gaccess: convert kvm_s390_check_low_addr_prot_real()
Let's use our new function for preparing translation exceptions.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:15 +02:00
David Hildenbrand
d03193de30 KVM: s390: gaccess: function for preparing translation exceptions
Let's provide a function trans_exc() that can be used for handling
preparation of translation exceptions on a central basis. We will use
that function to replace existing code in gaccess.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:14 +02:00
David Hildenbrand
6167375b55 KVM: s390: gaccess: store guest address on ALC prot exceptions
Let's pass the effective guest address to get_vcpu_asce(), so we
can properly set the guest address in case we inject an ALC protection
exception.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:14 +02:00
David Hildenbrand
34346b9a93 KVM: s390: gaccess: implement instruction fetching mode
When an instruction is to be fetched, special handling applies to
secondary-space mode and access-register mode. The instruction is to be
fetched from primary space.

We can easily support this by selecting the right asce for translation.
Access registers will never be used during translation, so don't
include them in the interface. As we only want to read from the current
PSW address for now, let's also hide that detail.

Reviewed-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>
2016-02-10 13:12:51 +01:00
David Hildenbrand
92c9632119 KVM: s390: gaccess: introduce access modes
We will need special handling when fetching instructions, so let's
introduce new guest access modes GACC_FETCH and GACC_STORE instead
of a write flag. An additional patch will then introduce GACC_IFETCH.

Reviewed-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>
2016-02-10 13:12:50 +01:00
Eugene (jno) Dvurechenski
5e04431523 KVM: s390: Introduce switching code
This patch adds code that performs transparent switch to Extended
SCA on addition of 65th VCPU in a VM. Disposal of ESCA is added too.
The entier ESCA functionality, however, is still not enabled.
The enablement will be provided in a separate patch.

This patch also uses read/write lock protection of SCA and its subfields for
possible disposal at the BSCA-to-ESCA transition. While only Basic SCA needs such
a protection (for the swap), any SCA access is now guarded.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:08 +01:00
Eugene (jno) Dvurechenski
605145103a KVM: s390: Generalize access to IPTE controls
This patch generalizes access to the IPTE controls, which is a part of SCA.
This is to prepare for upcoming introduction of Extended SCA support.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:06 +01:00
Thomas Huth
41408c28f2 KVM: s390: Add MEMOP ioctls for reading/writing guest memory
On s390, we've got to make sure to hold the IPTE lock while accessing
logical memory. So let's add an ioctl for reading and writing logical
memory to provide this feature for userspace, too.
The maximum transfer size of this call is limited to 64kB to prevent
that the guest can trigger huge copy_from/to_user transfers. QEMU
currently only requests up to one or two pages so far, so 16*4kB seems
to be a reasonable limit here.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-17 16:26:24 +01:00
Alexander Yarygin
664b497353 KVM: s390: Add access register mode
Access register mode is one of the modes that control dynamic address
translation. In this mode the address space is specified by values of
the access registers. The effective address-space-control element is
obtained from the result of the access register translation. See
the "Access-Register Introduction" section of the chapter 5 "Program
Execution" in "Principles of Operations" for more details.

Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-17 16:25:57 +01:00
Alexander Yarygin
75a1812230 KVM: s390: Optimize paths where get_vcpu_asce() is invoked
During dynamic address translation the get_vcpu_asce()
function can be invoked several times. It's ok for usual modes, but will
be slow if CPUs are in AR mode. Let's call the get_vcpu_asce() once and
pass the result to the called functions.

Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-17 16:25:31 +01:00
Alexander Yarygin
8ae04b8f50 KVM: s390: Guest's memory access functions get access registers
In access register mode, the write_guest() read_guest() and other
functions will invoke the access register translation, which
requires an ar, designated by one of the instruction fields.

Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-17 16:25:04 +01:00
Alexander Yarygin
dd9e5b7bdb KVM: s390: Fix low-address protection for real addresses
The kvm_s390_check_low_addr_protection() function is used only with real
addresses. According to the POP (the "Low-Address Protection"
paragraph in chapter 3), if the effective address is real or absolute,
the low-address protection procedure should raise a PROTECTION exception
only when the low-address protection is enabled in the control register
0 and the address is low.
This patch removes ASCE checks from the function and renames it to
better reflect its behavior.

Cc: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-17 16:24:38 +01:00
Yannick Guerrini
16b0fc13d6 KVM: s390: Fix trivial typo in comments
Change 'architecuture' to 'architecture'

Signed-off-by: Yannick Guerrini <yguerrini@tomshardware.fr>
Message-Id: <1424989004-14412-1-git-send-email-yguerrini@tomshardware.fr>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06 13:40:55 +01:00
Michael Mueller
9d8d578605 KVM: s390: use facilities and cpu_id per KVM
The patch introduces facilities and cpu_ids per virtual machine.
Different virtual machines may want to expose different facilities and
cpu ids to the guest, so let's make them per-vm instead of global.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-02-09 12:44:12 +01:00
Linus Torvalds
60815cf2e0 kernel: Provide READ_ONCE and ASSIGN_ONCE
As discussed on LKML http://marc.info/?i=54611D86.4040306%40de.ibm.com
 ACCESS_ONCE might fail with specific compilers for non-scalar accesses.
 
 Here is a set of patches to tackle that problem.
 
 The first patch introduce READ_ONCE and ASSIGN_ONCE. If the data structure
 is larger than the machine word size memcpy is used and a warning is emitted.
 The next patches fix up several in-tree users of ACCESS_ONCE on non-scalar
 types.
 
 This merge does not yet contain a patch that forces ACCESS_ONCE to work only
 on scalar types. This is targetted for the next merge window as Linux next
 already contains new offenders regarding ACCESS_ONCE vs. non-scalar types.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/borntraeger/linux

Pull ACCESS_ONCE cleanup preparation from Christian Borntraeger:
 "kernel: Provide READ_ONCE and ASSIGN_ONCE

  As discussed on LKML http://marc.info/?i=54611D86.4040306%40de.ibm.com
  ACCESS_ONCE might fail with specific compilers for non-scalar
  accesses.

  Here is a set of patches to tackle that problem.

  The first patch introduce READ_ONCE and ASSIGN_ONCE.  If the data
  structure is larger than the machine word size memcpy is used and a
  warning is emitted.  The next patches fix up several in-tree users of
  ACCESS_ONCE on non-scalar types.

  This does not yet contain a patch that forces ACCESS_ONCE to work only
  on scalar types.  This is targetted for the next merge window as Linux
  next already contains new offenders regarding ACCESS_ONCE vs.
  non-scalar types"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/borntraeger/linux:
  s390/kvm: REPLACE barrier fixup with READ_ONCE
  arm/spinlock: Replace ACCESS_ONCE with READ_ONCE
  arm64/spinlock: Replace ACCESS_ONCE READ_ONCE
  mips/gup: Replace ACCESS_ONCE with READ_ONCE
  x86/gup: Replace ACCESS_ONCE with READ_ONCE
  x86/spinlock: Replace ACCESS_ONCE with READ_ONCE
  mm: replace ACCESS_ONCE with READ_ONCE or barriers
  kernel: Provide READ_ONCE and ASSIGN_ONCE
2014-12-20 16:48:59 -08:00
Christian Borntraeger
5de72a2247 s390/kvm: REPLACE barrier fixup with READ_ONCE
ACCESS_ONCE does not work reliably on non-scalar types. For
example gcc 4.6 and 4.7 might remove the volatile tag for such
accesses during the SRA (scalar replacement of aggregates) step
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)

Commit 1365039d0c ("KVM: s390: Fix ipte locking") replace
ACCESS_ONCE with barriers. Lets use READ_ONCE instead.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-12-18 09:54:41 +01:00
Paolo Bonzini
173ede4ddd KVM: s390: Fixes for kvm/next (3.19) and stable
1. We should flush TLBs for load control instruction emulation (stable)
 2. A workaround for a compiler bug that renders ACCESS_ONCE broken (stable)
 3. Fix program check handling for load control
 4. Documentation Fix
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Merge tag 'kvm-s390-next-20141107' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Fixes for kvm/next (3.19) and stable

1. We should flush TLBs for load control instruction emulation (stable)
2. A workaround for a compiler bug that renders ACCESS_ONCE broken (stable)
3. Fix program check handling for load control
4. Documentation Fix
2014-11-07 15:39:44 +01:00
Christian Borntraeger
1365039d0c KVM: s390: Fix ipte locking
ipte_unlock_siif uses cmpxchg to replace the in-memory data of the ipte
lock together with ACCESS_ONCE for the intial read.

union ipte_control {
        unsigned long val;
        struct {
                unsigned long k  : 1;
                unsigned long kh : 31;
                unsigned long kg : 32;
        };
};
[...]
static void ipte_unlock_siif(struct kvm_vcpu *vcpu)
{
        union ipte_control old, new, *ic;

        ic = &vcpu->kvm->arch.sca->ipte_control;
        do {
                new = old = ACCESS_ONCE(*ic);
                new.kh--;
                if (!new.kh)
                        new.k = 0;
        } while (cmpxchg(&ic->val, old.val, new.val) != old.val);
        if (!new.kh)
                wake_up(&vcpu->kvm->arch.ipte_wq);
}

The new value, is loaded twice from memory with gcc 4.7.2 of
fedora 18, despite the ACCESS_ONCE:

--->

l       %r4,0(%r3)      <--- load first 32 bit of lock (k and kh) in r4
alfi    %r4,2147483647  <--- add -1 to r4
llgtr   %r4,%r4         <--- zero out the sign bit of r4
lg      %r1,0(%r3)      <--- load all 64 bit of lock into new
lgr     %r2,%r1         <--- load the same into old
risbg   %r1,%r4,1,31,32 <--- shift and insert r4 into the bits 1-31 of
new
llihf   %r4,2147483647
ngrk    %r4,%r1,%r4
jne     aa0 <ipte_unlock+0xf8>
nihh    %r1,32767
lgr     %r4,%r2
csg     %r4,%r1,0(%r3)
cgr     %r2,%r4
jne     a70 <ipte_unlock+0xc8>

If the memory value changes between the first load (l) and the second
load (lg) we are broken. If that happens VCPU threads will hang
(unkillable) in handle_ipte_interlock.

Andreas Krebbel analyzed this and tracked it down to a compiler bug in
that version:
"while it is not that obvious the C99 standard basically forbids
duplicating the memory access also in that case. For an argumentation of
a similiar case please see:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=22278#c43

For the implementation-defined cases regarding volatile there are some
GCC-specific clarifications which can be found here:
https://gcc.gnu.org/onlinedocs/gcc/Volatiles.html#Volatiles

I've tracked down the problem with a reduced testcase. The problem was
that during a tree level optimization (SRA - scalar replacement of
aggregates) the volatile marker is lost. And an RTL level optimizer (CSE
- common subexpression elimination) then propagated the memory read into
  its second use introducing another access to the memory location. So
indeed Christian's suspicion that the union access has something to do
with it is correct (since it triggered the SRA optimization).

This issue has been reported and fixed in the GCC 4.8 development cycle:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145"

This patch replaces the ACCESS_ONCE scheme with a barrier() based scheme
that should work for all supported compilers.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org # v3.16+
2014-11-07 11:10:26 +01:00
Thomas Huth
a6b7e459ff KVM: s390: Make the simple ipte mutex specific to a VM instead of global
The ipte-locking should be done for each VM seperately, not globally.
This way we avoid possible congestions when the simple ipte-lock is used
and multiple VMs are running.

Suggested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-10-28 13:08:59 +01:00
Christian Borntraeger
6b331952f1 KVM: s390: get rid of constant condition in ipte_unlock_simple
Due to the earlier check we know that ipte_lock_count must be 0.
No need to add a useless if. Let's make clear that we are going
to always wakeup when we execute that code.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-09-10 12:19:38 +02:00
Thomas Huth
a0465f9ae4 KVM: s390: Enable DAT support for TPROT handler
The TPROT instruction can be used to check the accessability of storage
for any kind of logical addresses. So far, our handler only supported
real addresses. This patch now also enables support for addresses that
have to be translated via DAT first. And while we're at it, change the
code to use the common KVM function gfn_to_hva_prot() to check for the
validity and writability of the memory page.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-05-30 09:39:36 +02:00