When test GVTg as below scenario:
VM boot --> failsafe --> kill qemu --> VM boot.
Qemu report error at the second boot:
ERROR: PCI region size must be pow2 type=0x0, size=0x1fa1000
Qemu need access PCI_ROM_ADDRESS reg to determine the size of expansion
PCI rom. The mechanism just like the BAR reg (write-read) and we should
return the size 0 since we have no rom. If we reject the write to
PCI_ROM_ADDRESS, Qemu cannot get the correct size of rom.
Essentially, GVTg failsafe mode should not break PCI function. So we
exclude cfg space from failsafe mode. This can fix above issue.
v2: add Fixes and Bugzilla link.
Fixes: fd64be6367 ("drm/i915/gvt: introduced failsafe mode into vgpu")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100296
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Per PCI specification, Configuration Register has different types (RO,
RW, RW1C, Rsvd). For RO Register bits are read-only and cannot be
altered by software. For RW1C Register bits indicate status when read.
A Set bit indicates a status event which is Cleared by writing a 1b.
Writing a 0b to RW1C bits has no effect. Reserved Register is for future
implementations, and they are read-only and must return zero when read.
Current vGPU configuration write emulation just copy the value as it is.
So we haven't emulated RO, RW1C and Rsvd Registers correctly. This patch
is following the Spec to correct emulation logic. We add a function
vgpu_cfg_mem_write to wrap the access to vGPU configuration memory.
The write function uses a RW Register bitmap to avoid RO bits be
overwritten, and emulate RW1C behavior for the particular status Register.
v2:
new = src[i] --> new = src[i] & mask (zhenyu)
Signed-off-by: Changbin Du <changbin.du@intel.com>
Cc: Xiaoguang Chen <xiaoguang.chen@intel.com>
Cc: Zhiyuan Lv <zhiyuan.lv@intel.com>
Cc: Min He <min.he@intel.com>
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
New failsafe mode is introduced, when we detect guest not supporting
GVT-g.
In failsafe mode, we will ignore all the MMIO and cfg space read/write
from guest.
This patch can fix the issue that when guest kernel or graphics driver
version is too low, there will be a lot of kernel traces in host.
V5: rebased onto latest gvt-staging
V4: changed coding style by Zhenyu and Ping's advice
V3: modified coding style and error messages according to Zhenyu's comment
V2: 1) implemented MMIO/GTT/WP pages read/write logic; 2) used a unified
function to enter failsafe mode
Signed-off-by: Min He <min.he@intel.com>
Signed-off-by: Pei Zhang <pei.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces a new function intel_vgpu_reset_cfg_space()
to reset vGPU configuration space. This function will unmap gttmmio
and aperture if they are mapped before. Then entire cfg space will
be restored to default values.
Currently we only do such reset when vGPU is not owned by any VM
so we simply restore entire cfg space to default value, not following
the PCIe FLR spec that some fields should remain unchanged.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Move the configuration space inititation function setup_vgpu_cfg_space()
in vgpu.c to dedicated source file cfg_space.c, and rename the function
as intel_vgpu_init_cfg_space().
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
PCI basic config space's size is 256 bytes. When check if access crosses
space range, should use "> 256".
Signed-off-by: Pei Zhang <pei.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
There's an issue in current cfg space emulation for PCI_COMMAND (offset
0x4): when guest changes some bits other than PCI_COMMAND_MEMORY, this
write operation will not be written to virutal cfg space successfully.
This patch is to fix the wrong behavior above.
Signed-off-by: Min He <min.he@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
There are currently 4 methods in intel_gvt_io_emulation_ops
to emulate CFG/MMIO reading/writing for intel vGPU. A possibly
better scope is: add 3 more methods for vgpu create/destroy/reset
respectively, and rename the ops to 'intel_gvt_ops', then pass
it to the MPT module (say the future kvmgt) to use: they are
all methods for external usage.
Signed-off-by: Jike Song <jike.song@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Current GVT contains some obsolete logic originally cooked to
support the old, non-vfio kvmgt, which is actually workarounds.
We don't support that anymore, so it's safe to remove it and
make a better framework.
Signed-off-by: Jike Song <jike.song@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
i915 core should only call functions and structures exposed through
intel_gvt.h. Remove internal gvt.h and i915_pvinfo.h.
Change for internal intel_gvt structure as private handler which
not requires to expose gvt internal structure for i915 core.
v2: Fix per Chris's comment
- carefully handle dev_priv->gvt assignment
- add necessary bracket for macro helper
- forward declartion struct intel_gvt
- keep free operation within same file handling alloc
v3: fix use after free and remove intel_gvt.initialized
v4: change to_gvt() to an inline
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces vGPU PCI configuration space virtualization.
- Adjust the trapped GPFN(Guest Page Frame Number) window of virtual GEN
PCI BAR 0 when guest initializes PCI BAR 0 address.
- Emulate OpRegion when guest touches OpRegion.
- Pass-through a part of aperture to guest when guest initializes
aperture BAR.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
