As a rule, CPU internal state should never be updated when
!cpu->kvm_vcpu_dirty (or the HAX equivalent). If that is done, then
subsequent calls to cpu_synchronize_state() - usually safe and idempotent -
will clobber state.
However, we routinely do this during a loadvm or incoming migration.
Usually this is called shortly after a reset, which will clear all the cpu
dirty flags with cpu_synchronize_all_post_reset(). Nothing is expected
to set the dirty flags again before the cpu state is loaded from the
incoming stream.
This means that it isn't safe to call cpu_synchronize_state() from a
post_load handler, which is non-obvious and potentially inconvenient.
We could cpu_synchronize_all_state() before the loadvm, but that would be
overkill since a) we expect the state to already be synchronized from the
reset and b) we expect to completely rewrite the state with a call to
cpu_synchronize_all_post_init() at the end of qemu_loadvm_state().
To clear this up, this patch introduces cpu_synchronize_pre_loadvm() and
associated helpers, which simply marks the cpu state as dirty without
actually changing anything. i.e. it says we want to discard any existing
KVM (or HAX) state and replace it with what we're going to load.
Cc: Juan Quintela <quintela@redhat.com>
Cc: Dave Gilbert <dgilbert@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Juan Quintela <quintela@redhat.com>
That's a forward port of the core HAX interface code from the
emu-2.2-release branch in the external/qemu-android repository as used by
the Android emulator.
The original commit was "target/i386: Add Intel HAX to android emulator"
saying:
"""
Backport of 2b3098ff27bab079caab9b46b58546b5036f5c0c
from studio-1.4-dev into emu-master-dev
Intel HAX (harware acceleration) will enhance android emulator performance
in Windows and Mac OS X in the systems powered by Intel processors with
"Intel Hardware Accelerated Execution Manager" package installed when
user runs android emulator with Intel target.
Signed-off-by: David Chou <david.j.chou@intel.com>
"""
It has been modified to build and run along with the current code base.
The formatting has been fixed to go through scripts/checkpatch.pl,
and the DPRINTF macros have been updated to get the instanciations checked by
the compiler.
The FPU registers saving/restoring has been updated to match the current
QEMU registers layout.
The implementation has been simplified by doing the following modifications:
- removing the code for supporting the hardware without Unrestricted Guest (UG)
mode (including all the code to fallback on TCG emulation).
- not including the Darwin support (which is not yet debugged/tested).
- simplifying the initialization by removing the leftovers from the Android
specific code, then trimming down the remaining logic.
- removing the unused MemoryListener callbacks.
Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Message-Id: <e1023837f8d0e4c470f6c4a3bf643971b2bca5be.1484045952.git.vpalatin@chromium.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
