linux/arch/mips/kvm
James Hogan 5fb59fd2e7 MIPS: KVM/locore.S: Don't preserve host ASID around vcpu_run
MIPS KVM uses different ASIDs for guest execution than for the host.
The host ASID is saved on the stack when entering the guest with
__kvm_mips_vcpu_run(), and restored again before returning back to the
caller (exit to userland).

- This does not take into account that pre-emption may have taken place
  during that time, which may have started a new ASID cycle and resulted
  in that process' ASID being invalidated and reused.

- This does not take into account that the process may have migrated to
  a different CPU during that time, with a different ASID assignment
  since they are managed per-CPU.

- It is actually redundant, since the host ASID will be restored
  correctly by kvm_arch_vcpu_put(), which is called almost immediately
  after kvm_arch_vcpu_ioctl_run() returns.

Therefore drop this code from locore.S

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13206/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:18 +02:00
..
00README.txt KVM/MIPS32: Release notes and KVM module Makefile 2013-05-08 03:55:35 +02:00
callback.c MIPS: KVM: Convert EXPORT_SYMBOL to _GPL 2016-01-24 03:13:24 +01:00
commpage.c MIPS: KVM: Skip memory cleaning in kvm_mips_commpage_init() 2014-06-30 16:52:03 +02:00
commpage.h MIPS: KVM: Rename files to remove the prefix "kvm_" and "kvm_mips_" 2014-06-30 16:52:03 +02:00
dyntrans.c MIPS: KVM: Refactor added offsetof()s 2016-01-24 03:14:15 +01:00
emulate.c Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2016-01-24 12:50:56 -08:00
fpu.S MIPS: KVM: Add base guest FPU support 2015-03-27 21:25:14 +00:00
interrupt.c MIPS: Move Cause.ExcCode trap codes to mipsregs.h 2016-01-24 03:15:51 +01:00
interrupt.h MIPS: KVM: Rename files to remove the prefix "kvm_" and "kvm_mips_" 2014-06-30 16:52:03 +02:00
Kconfig rcu: Make SRCU optional by using CONFIG_SRCU 2015-01-06 11:04:29 -08:00
locore.S MIPS: KVM/locore.S: Don't preserve host ASID around vcpu_run 2016-05-13 14:02:18 +02:00
Makefile MIPS: KVM: Add base guest MSA support 2015-03-27 21:25:19 +00:00
mips.c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-14 19:14:06 -07:00
msa.S MIPS: KVM: Add base guest MSA support 2015-03-27 21:25:19 +00:00
stats.c MIPS: KVM: Add MSA exception handling 2015-03-27 21:25:20 +00:00
tlb.c MIPS: Fix misspellings in comments. 2016-04-03 12:32:09 +02:00
trace.h KVM: MIPS: Fix trace event to save PC directly 2015-03-02 19:17:52 -03:00
trap_emul.c MIPS: Fix misspellings in comments. 2016-04-03 12:32:09 +02:00