[PATCH 00/21] MIPS: KVM: Fixes and guest timer rewrite

James Hogan
2014-04-25T15:19:43Z

Here are a range of MIPS KVM T&E fixes for v3.16. They can also be found
on my kvm_mips_queue branch here:
git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/kvm-mips.git

They originally served to allow it to work better on Ingenic XBurst
cores which have some peculiarities which break non-portable assumptions
in the MIPS KVM implementation (patches 1-3, 11).

Fixing guest CP0_Count emulation to work without a running host
CP0_Count (patch 11) however required a rewrite of the timer emulation
code to use the kernel monotonic time instead, which needed doing anyway
since basing it directly off the host CP0_Count was broken. Various bugs
were fixed in the process (patches 8-10) and improvements made thanks to
valuable feedback from Paolo Bonzini for the last QEMU MIPS/KVM patchset
(patches 4-7, 13-15).

Finally there are some misc cleanups which I did along the way (patches
16-21).

Only the first patch (fixes MIPS KVM with 4K pages) is marked for
stable. For KVM to work on XBurst it needs the timer rework which is a
fairly complex change, so there's little point marking any of the XBurst
specific changes for stable.

All feedback welcome!

Patches 1-3:
Fix KVM/MIPS with 4K pages, missing RDHWR SYNCI (XBurst),
unmoving CP0_Random (XBurst).
Patches 4-7:
Add EPC, Count, Compare guest CP0 registers to KVM register
ioctl interface.
Patches 8-10:
Fix a few potential races relating to timers.
Patches 11-12:
Rewrite guest timer emulation to use ktime_get().
Patches 13-15:
Add KVM virtual registers for controlling guest timer, including
master timer disable, nanosecond bias, and timer frequency.
Patches 16-21:
Cleanups.

James Hogan (21):
MIPS: KVM: Allocate at least 16KB for exception handlers
MIPS: KVM: Use local_flush_icache_range to fix RI on XBurst
MIPS: KVM: Use tlb_write_random
MIPS: KVM: Fix CP0_EBASE KVM register id
MIPS: KVM: Add CP0_EPC KVM register access
MIPS: KVM: Move KVM_{GET,SET}_ONE_REG definitions into kvm_host.h
MIPS: KVM: Add CP0_Count/Compare KVM register access
MIPS: KVM: Deliver guest interrupts after local_irq_disable()
MIPS: KVM: Fix timer race modifying guest CP0_Cause
MIPS: KVM: Migrate hrtimer to follow VCPU
MIPS: KVM: Rewrite count/compare timer emulation
MIPS: KVM: Override guest kernel timer frequency directly
MIPS: KVM: Add master disable count interface
MIPS: KVM: Add nanosecond count bias KVM register
MIPS: KVM: Add count frequency KVM register
MIPS: KVM: Make kvm_mips_comparecount_{func,wakeup} static
MIPS: KVM: Whitespace fixes in kvm_mips_callbacks
MIPS: KVM: Fix kvm_debug bit-rottage
MIPS: KVM: Remove ifdef DEBUG around kvm_debug
MIPS: KVM: Quieten kvm_info() logging
MIPS: KVM: Remove redundant NULL checks before kfree()

arch/mips/Kconfig | 12 +-
arch/mips/include/asm/kvm_host.h | 185 +++++++++---
arch/mips/include/uapi/asm/kvm.h | 40 +++
arch/mips/kvm/kvm_locore.S | 32 --
arch/mips/kvm/kvm_mips.c | 127 ++++----
arch/mips/kvm/kvm_mips_dyntrans.c | 15 +-
arch/mips/kvm/kvm_mips_emul.c | 608 ++++++++++++++++++++++++++++++++++++--
arch/mips/kvm/kvm_tlb.c | 60 ++--
arch/mips/kvm/kvm_trap_emul.c | 89 +++++-
arch/mips/mti-malta/malta-time.c | 14 +-
10 files changed, 951 insertions(+), 231 deletions(-)

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: kvm@vger.kernel.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: David Daney <david.daney@cavium.com>