Commit Graph

2 Commits

Author SHA1 Message Date
Yu Ning
8a3c3d996e hax: Fix memory mapping de-duplication logic
hax_update_mapping() avoids unnecessary and potentially expensive
calls to HAX_VM_IOCTL_SET_RAM by computing the net result (i.e.
effective mapping changes) of each MemoryRegion transaction, with
the help of a linked list of HAXMapping objects.

However, when processing a new mapping that overlaps with an
existing mapping in the list, it fails to handle the case where the
start address of the new mapping is above that of the existing
mapping in the guest physical address space. This happens when QEMU
is launched with "-machine q35 -enable-hax", which involves the
following MemoryRegion transaction for digging the VGA hole:

 region_del: 0x00000000->0x08000000 VA 05fa0000 ('pc.ram')
 region_add: 0x00000000->0x000a0000 VA 05fa0000 ('pc.ram')
 region_add: 0x000a0000->0x000c0000 VA 00000000 ('vga-lowmem')
 region_add: 0x000c0000->0x08000000 VA 06060000 ('pc.ram')

where the third MemoryRegion is MMIO and is ignored. The current
de-duplication logic handles the last MemoryRegion incorrectly and
produces the following result:

 hax_mapping_dump_list updates:
         + 0x000c0000->0x08000000 VA 0x06060000
         - 0x07fe0000->0x08000000 VA 0x0df80000

which is why VGA emulation does not work for Q35.

With this patch, one can see VGA output as Q35 boots up. Note that
Q35 support also requires a change to HAXM kernel module, which is
not available in the current HAXM release (6.1.2).

+ Add a warning if the input MemoryRegion is a ROM device, which is
  not supported by HAXM kernel module at this time.

Signed-off-by: Yu Ning <yu.ning@linux.intel.com>
Message-Id: <20170428072723.7036-1-yu.ning@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-05 12:10:00 +02:00
Vincent Palatin
47c1c8c12f target/i386: Add Intel HAX files
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>
2017-01-19 22:07:46 +01:00