linux.git/arch/s390, branch v4.17

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2018-05-30T15:30:30+00:00

Pull s390 fixes from Martin Schwidefsky:

 - a missing -msoft-float for the compile of the kexec purgatory

 - a fix for the dasd driver to avoid the double use of a field in the
   'struct request'

[ That latter one is being discussed, and Christoph asked for something
  cleaner, but for now it's a fix ]

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/dasd: use blk_mq_rq_from_pdu for per request data
  s390/purgatory: Fix endless interrupt loop

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2018-05-26T17:46:57+00:00

Pull KVM fixes from Radim Krčmář:
 "PPC:

   - Close a hole which could possibly lead to the host timebase getting
     out of sync.

   - Three fixes relating to PTEs and TLB entries for radix guests.

   - Fix a bug which could lead to an interrupt never getting delivered
     to the guest, if it is pending for a guest vCPU when the vCPU gets
     offlined.

  s390:

   - Fix false negatives in VSIE validity check (Cc stable)

  x86:

   - Fix time drift of VMX preemption timer when a guest uses LAPIC
     timer in periodic mode (Cc stable)

   - Unconditionally expose CPUID.IA32_ARCH_CAPABILITIES to allow
     migration from hosts that don't need retpoline mitigation (Cc
     stable)

   - Fix guest crashes on reboot by properly coupling CR4.OSXSAVE and
     CPUID.OSXSAVE (Cc stable)

   - Report correct RIP after Hyper-V hypercall #UD (introduced in
     -rc6)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: fix #UD address of failed Hyper-V hypercalls
  kvm: x86: IA32_ARCH_CAPABILITIES is always supported
  KVM: x86: Update cpuid properly when CR4.OSXAVE or CR4.PKE is changed
  x86/kvm: fix LAPIC timer drift when guest uses periodic mode
  KVM: s390: vsie: fix < 8k check for the itdba
  KVM: PPC: Book 3S HV: Do ptesync in radix guest exit path
  KVM: PPC: Book3S HV: XIVE: Resend re-routed interrupts on CPU priority change
  KVM: PPC: Book3S HV: Make radix clear pte when unmapping
  KVM: PPC: Book3S HV: Make radix use correct tlbie sequence in kvmppc_radix_tlbie_page
  KVM: PPC: Book3S HV: Snapshot timebase offset on guest entry

s390/purgatory: Fix endless interrupt loop

2018-05-18T05:24:35+00:00

New compilers use the floating-point registers as spill registers when
there is high register pressure. In the purgatory however, the afp control
bit is not set. This leads to an exception whenever a floating-point
instruction is used, which again causes an interrupt loop.

Forbid the compiler to use floating-point instructions by adding
-msoft-float to KBUILD_CFLAGS.

Signed-off-by: Philipp Rudo 
Fixes: 840798a1f529 (s390/kexec_file: Add purgatory)
Reviewed-by: Hendrik Brueckner 
Signed-off-by: Martin Schwidefsky

KVM: s390: vsie: fix < 8k check for the itdba

2018-05-17T10:28:45+00:00

By missing an "L", we might detect some addresses to be <8k,
although they are not.

e.g. for itdba = 100001fff
!(gpa & ~0x1fffU) -> 1
!(gpa & ~0x1fffUL) -> 0

So we would report a SIE validity intercept although everything is fine.

Fixes: 166ecb3 ("KVM: s390: vsie: support transactional execution")
Reported-by: Dan Carpenter 
Reviewed-by: Christian Borntraeger 
Reviewed-by: Janosch Frank 
Reviewed-by: Cornelia Huck 
Signed-off-by: David Hildenbrand 
Signed-off-by: Janosch Frank 
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Christian Borntraeger

s390/cpum_sf: ensure sample frequency of perf event attributes is non-zero

2018-05-08T13:56:36+00:00

Correct a trinity finding for the perf_event_open() system call with
a perf event attribute structure that uses a frequency but has the
sampling frequency set to zero.  This causes a FP divide exception during
the sample rate initialization for the hardware sampling facility.

Fixes: 8c069ff4bd606 ("s390/perf: add support for the CPU-Measurement Sampling Facility")
Cc: stable@vger.kernel.org # 3.14+
Reviewed-by: Heiko Carstens 
Signed-off-by: Hendrik Brueckner 
Signed-off-by: Martin Schwidefsky

s390: use expoline thunks in the BPF JIT

2018-05-07T19:12:43+00:00

The BPF JIT need safe guarding against spectre v2 in the sk_load_xxx
assembler stubs and the indirect branches generated by the JIT itself
need to be converted to expolines.

Signed-off-by: Martin Schwidefsky

s390: extend expoline to BC instructions

2018-05-07T19:12:42+00:00

The BPF JIT uses a 'b (%r)' instruction in the definition
of the sk_load_word and sk_load_half functions.

Add support for branch-on-condition instructions contained in the
thunk code of an expoline.

Signed-off-by: Martin Schwidefsky

s390: remove indirect branch from do_softirq_own_stack

2018-05-07T19:12:42+00:00

The inline assembly to call __do_softirq on the irq stack uses
an indirect branch. This can be replaced with a normal relative
branch.

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

s390: move spectre sysfs attribute code

2018-05-07T19:12:41+00:00

The nospec-branch.c file is compiled without the gcc options to
generate expoline thunks. The return branch of the sysfs show
functions cpu_show_spectre_v1 and cpu_show_spectre_v2 is an indirect
branch as well. These need to be compiled with expolines.

Move the sysfs functions for spectre reporting to a separate file
and loose an '.' for one of the messages.

Cc: stable@vger.kernel.org # 4.16
Fixes: d424986f1d ("s390: add sysfs attributes for spectre")
Signed-off-by: Martin Schwidefsky

s390/kernel: use expoline for indirect branches

2018-05-07T19:12:39+00:00

The assember code in arch/s390/kernel uses a few more indirect branches
which need to be done with execute trampolines for CONFIG_EXPOLINE=y.

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