linux.git/arch/powerpc, branch v4.8-rc2

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

2016-08-13T17:11:14+00:00

Pull KVM fixes from Radim Krčmář:
 "KVM:
   - lock kvm_device list to prevent corruption on device creation.

  PPC:
   - split debugfs initialization from creation of the xics device to
     unlock the newly taken kvm lock earlier.

  s390:
   - prevent userspace from triggering two WARN_ON_ONCE.

  MIPS:
   - fix several issues in the management of TLB faults (Cc: stable)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  MIPS: KVM: Propagate kseg0/mapped tlb fault errors
  MIPS: KVM: Fix gfn range check in kseg0 tlb faults
  MIPS: KVM: Add missing gfn range check
  MIPS: KVM: Fix mapped fault broken commpage handling
  KVM: Protect device ops->create and list_add with kvm->lock
  KVM: PPC: Move xics_debugfs_init out of create
  KVM: s390: reset KVM_REQ_MMU_RELOAD if mapping the prefix failed
  KVM: s390: set the prefix initially properly

Merge tag 'powerpc-4.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2016-08-12T19:09:44+00:00

Pull powerpc fixes from Michael Ellerman:
 "Some powerpc fixes for 4.8:

  Misc:
   - powerpc/vdso: Fix build rules to rebuild vdsos correctly from Nicholas Piggin
   - powerpc/ptrace: Fix coredump since ptrace TM changes from Cyril Bur
   - powerpc/32: Fix csum_partial_copy_generic() from Christophe Leroy
   - cxl: Set psl_fir_cntl to production environment value from Frederic Barrat
   - powerpc/eeh: Switch to conventional PCI address output in EEH log from Guilherme G. Piccoli
   - cxl: Use fixed width predefined types in data structure. from Philippe Bergheaud
   - powerpc/vdso: Add missing include file from Guenter Roeck
   - powerpc: Fix unused function warning 'lmb_to_memblock' from Alastair D'Silva
   - powerpc/powernv/ioda: Fix TCE invalidate to work in real mode again from Alexey Kardashevskiy
   - powerpc/cell: Add missing error code in spufs_mkgang() from Dan Carpenter
   - crypto: crc32c-vpmsum - Convert to CPU feature based module autoloading from Anton Blanchard
   - powerpc/pasemi: Fix coherent_dma_mask for dma engine from Darren Stevens

  Benjamin Herrenschmidt:
   - powerpc/32: Fix crash during static key init
   - powerpc: Update obsolete comment in setup_32.c about early_init()
   - powerpc: Print the kernel load address at the end of prom_init()
   - powerpc/pnv/pci: Fix incorrect PE reservation attempt on some 64-bit BARs
   - powerpc/xics: Properly set Edge/Level type and enable resend

  Mahesh Salgaonkar:
   - powerpc/book3s: Fix MCE console messages for unrecoverable MCE.
   - powerpc/powernv: Fix MCE handler to avoid trashing CR0/CR1 registers.
   - powerpc/powernv: Move IDLE_STATE_ENTER_SEQ macro to cpuidle.h
   - powerpc/powernv: Load correct TOC pointer while waking up from winkle.

  Andrew Donnellan:
   - cxl: Fix sparse warnings
   - cxl: Fix NULL dereference in cxl_context_init() on PowerVM guests

  Michael Ellerman:
   - selftests/powerpc: Specify we expect to build with std=gnu99
   - powerpc/Makefile: Use cflags-y/aflags-y for setting endian options
   - powerpc/pci: Fix endian bug in fixed PHB numbering"

* tag 'powerpc-4.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (26 commits)
  selftests/powerpc: Specify we expect to build with std=gnu99
  powerpc/vdso: Fix build rules to rebuild vdsos correctly
  powerpc/Makefile: Use cflags-y/aflags-y for setting endian options
  powerpc/32: Fix crash during static key init
  powerpc: Update obsolete comment in setup_32.c about early_init()
  powerpc: Print the kernel load address at the end of prom_init()
  powerpc/ptrace: Fix coredump since ptrace TM changes
  powerpc/32: Fix csum_partial_copy_generic()
  cxl: Set psl_fir_cntl to production environment value
  powerpc/pnv/pci: Fix incorrect PE reservation attempt on some 64-bit BARs
  powerpc/book3s: Fix MCE console messages for unrecoverable MCE.
  powerpc/pci: Fix endian bug in fixed PHB numbering
  powerpc/eeh: Switch to conventional PCI address output in EEH log
  cxl: Fix sparse warnings
  cxl: Fix NULL dereference in cxl_context_init() on PowerVM guests
  cxl: Use fixed width predefined types in data structure.
  powerpc/vdso: Add missing include file
  powerpc: Fix unused function warning 'lmb_to_memblock'
  powerpc/powernv: Fix MCE handler to avoid trashing CR0/CR1 registers.
  powerpc/powernv: Move IDLE_STATE_ENTER_SEQ macro to cpuidle.h
  ...

KVM: Protect device ops->create and list_add with kvm->lock

2016-08-12T10:01:27+00:00

KVM devices were manipulating list data structures without any form of
synchronization, and some implementations of the create operations also
suffered from a lack of synchronization.

Now when we've split the xics create operation into create and init, we
can hold the kvm->lock mutex while calling the create operation and when
manipulating the devices list.

The error path in the generic code gets slightly ugly because we have to
take the mutex again and delete the device from the list, but holding
the mutex during anon_inode_getfd or releasing/locking the mutex in the
common non-error path seemed wrong.

Signed-off-by: Christoffer Dall 
Reviewed-by: Paolo Bonzini 
Acked-by: Christian Borntraeger 
Signed-off-by: Radim Krčmář

KVM: PPC: Move xics_debugfs_init out of create

2016-08-12T10:01:26+00:00

As we are about to hold the kvm->lock during the create operation on KVM
devices, we should move the call to xics_debugfs_init into its own
function, since holding a mutex over extended amounts of time might not
be a good idea.

Introduce an init operation on the kvm_device_ops struct which cannot
fail and call this, if configured, after the device has been created.

Signed-off-by: Christoffer Dall 
Reviewed-by: Paolo Bonzini 
Signed-off-by: Radim Krčmář

powerpc/vdso: Fix build rules to rebuild vdsos correctly

2016-08-10T13:04:12+00:00

When using if_changed, we need to add FORCE as a dependency (see
Documentation/kbuild/makefiles.txt) otherwise we don't get command line
change checking amongst other things. This has resulted in vdsos not
being rebuilt when switching between big and little endian.

The vdso64/32ld commands have to be changed around to avoid pulling
FORCE into the linker command line (code copied from x86).

Signed-off-by: Nicholas Piggin 
Signed-off-by: Michael Ellerman

powerpc/Makefile: Use cflags-y/aflags-y for setting endian options

2016-08-10T13:01:53+00:00

When we introduced the little endian support, we added the endian flags
to CC directly using override. I don't know the history of why we did
that, I suspect no one does.

Although this mostly works, it has one bug, which is that CROSS32CC
doesn't get -mbig-endian. That means when the compiler is little endian
by default and the user is building big endian, vdso32 is incorrectly
compiled as little endian and the kernel fails to build.

Instead we can add the endian flags to cflags-y/aflags-y, and then
append those to KBUILD_CFLAGS/KBUILD_AFLAGS.

This has the advantage of being 1) less ugly, 2) the documented way of
adding flags in the arch Makefile and 3) it fixes building vdso32 with a
LE toolchain.

Signed-off-by: Michael Ellerman

powerpc/32: Fix crash during static key init

2016-08-10T09:41:58+00:00

We cannot do those initializations from apply_feature_fixups() as
this function runs in a very restricted environment on 32-bit where
the kernel isn't running at its linked address and the PTRRELOC()
macro must be used for any global accesss.

Instead, split them into a separtate steup_feature_keys() function
which is called in a more suitable spot on ppc32.

Fixes: 309b315b6ec6 ("powerpc: Call jump_label_init() in apply_feature_fixups()")
Reported-and-tested-by: Christian Kujau 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman

powerpc: Update obsolete comment in setup_32.c about early_init()

2016-08-10T09:38:02+00:00

We don't identify the machine type anymore...

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman

powerpc: Print the kernel load address at the end of prom_init()

2016-08-10T09:37:43+00:00

This makes it easier to debug crashes that happen very early before
the kernel takes over Open Firmware by allowing us to relate the OF
reported crashing addresses to offsets within the kernel.

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman

powerpc/ptrace: Fix coredump since ptrace TM changes

2016-08-10T06:34:20+00:00

Commit 8d460f6156cd ("powerpc/process: Add the function
flush_tmregs_to_thread") added flush_tmregs_to_thread() and included
the assumption that it would only be called for a task which is not
current.

Although this is correct for ptrace, when generating a core dump, some
of the routines which call flush_tmregs_to_thread() are called. This
leads to a WARNing such as:

  Not expecting ptrace on self: TM regs may be incorrect
  ------------[ cut here ]------------
  WARNING: CPU: 123 PID: 7727 at arch/powerpc/kernel/process.c:1088 flush_tmregs_to_thread+0x78/0x80
  CPU: 123 PID: 7727 Comm: libvirtd Not tainted 4.8.0-rc1-gcc6x-g61e8a0d #1
  task: c000000fe631b600 task.stack: c000000fe63b0000
  NIP: c00000000001a1a8 LR: c00000000001a1a4 CTR: c000000000717780
  REGS: c000000fe63b3420 TRAP: 0700   Not tainted  (4.8.0-rc1-gcc6x-g61e8a0d)
  MSR: 900000010282b033   CR: 28004222  XER: 20000000
  ...
  NIP [c00000000001a1a8] flush_tmregs_to_thread+0x78/0x80
  LR [c00000000001a1a4] flush_tmregs_to_thread+0x74/0x80
  Call Trace:
   flush_tmregs_to_thread+0x74/0x80 (unreliable)
   vsr_get+0x64/0x1a0
   elf_core_dump+0x604/0x1430
   do_coredump+0x5fc/0x1200
   get_signal+0x398/0x740
   do_signal+0x54/0x2b0
   do_notify_resume+0x98/0xb0
   ret_from_except_lite+0x70/0x74

So fix flush_tmregs_to_thread() to detect the case where it is called on
current, and a transaction is active, and in that case flush the TM regs
to the thread_struct.

This patch also moves flush_tmregs_to_thread() into ptrace.c as it is
only called from that file.

Fixes: 8d460f6156cd ("powerpc/process: Add the function flush_tmregs_to_thread")
Signed-off-by: Cyril Bur 
[mpe: Flesh out change log]
Signed-off-by: Michael Ellerman