The VT-d spec (section 6.5.2) prescribes software to zero the
Invalidation Queue Tail Register before enabling the VTD_GCMD_QIE
Global Command Register bit. Windows Server 2012 R2 and possibly
other older Windows versions violate the protocol and set a
non-zero queue tail first, which in effect makes them crash early
on boot with -device intel-iommu,intremap=on.
This commit relaxes the check and instead of failing to enable
VTD_GCMD_QIE with vtd_err_qi_enable, it behaves as if the tail
register was set just after enabling VTD_GCMD_QIE
(see vtd_handle_iqt_write).
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Virtio serial device controls the lifetime of virtio-serial-bus and
virtio-serial-bus links back to the device via its hotplug-handler
property. This extra ref-count prevents the device from getting
finalized, leaving the VirtIODevice memory listener registered and
leading to use-after-free later on.
This patch addresses the same issue as Fam Zheng's
"virtio-scsi: Unset hotplug handler when unrealize"
only for a different virtio device.
Cc: qemu-stable@nongnu.org
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
PORT_STAT_C_SUSPEND should be set even on host-initiated wake-up,
i.e. on ClearPortFeature(PORT_SUSPEND). Windows is known to not
work properly otherwise.
Side note, since PORT_ENABLE looks similar and might appear to
have the same issue: According to 11.24.2.7.2.2 C_PORT_ENABLE:
"This bit is set when the PORT_ENABLE bit changes from one to
zero as a result of a Port Error condition (see Section 11.8.1).
This bit is not set on any other changes to PORT_ENABLE."
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Message-id: 20170522123325.2199-1-lprosek@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
For reasons unknown, Windows won't online all memory, both at command
line and hot-plugged later, unless the hotplug mem hole SRAT entry
specifies a node greater than or equal to the ones where memory is
added.
Using the highest node on the machine makes recent versions of Windows
happy.
With this example command line:
... \
-m 1024,slots=4,maxmem=32G \
-numa node,nodeid=0 \
-numa node,nodeid=1 \
-numa node,nodeid=2 \
-numa node,nodeid=3 \
-object memory-backend-ram,size=1G,id=mem-mem1 \
-device pc-dimm,id=dimm-mem1,memdev=mem-mem1,node=1
Windows reports a total of 1G of RAM without this commit and the expected
2G with this commit.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
The strict td link limit added by commit "05f43d4 xhci: limit the
number of link trbs we are willing to process" causes problems with
Windows guests. Let's raise the limit.
This change is analogous to:
commit ab6b1105a2
Author: Gerd Hoffmann <kraxel@redhat.com>
Date: Tue Mar 7 09:40:18 2017 +0100
ohci: relax link check
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Message-id: 20170512102100.22675-1-lprosek@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The spec says:
Suspend: (PORT_SUSPEND) This field indicates whether or not the device
on this port is suspended. Setting this field causes the device to
suspend by not propagating bus traffic downstream. This field may be
reset by a request or by resume signaling from the device attached to
the port.
I can't find any specific statement like "the PORT_SUSPEND field is reset
automatically on remote wakeup", but without this patch, the only way to
reset it is via the ClearPortFeature request so the ".. or by resume
signaling from the device" clause is clearly not implemented on the remote
wakeup path.
The default xhci Windows driver does not issue the ClearPortFeature request
and suspended devices attached to a hub don't properly get out of the
suspended state. Interestingly, the default uhci Windows driver *does*
issue the ClearPortFeature request and does not exhibit this problem.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Message-id: 20170511125314.24549-3-lprosek@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
virtio_input_send buffers input events until it sees a SYNC. Then it
either sends or drops the entire batch, depending on whether eventq
has enough space available. The case to avoid here is partial sends
where only part of the batch would get to the guest.
Using virtqueue_get_avail_bytes to check the state of eventq was not
correct. The queue may have a smaller number of larger buffers
available so bytes may be enough but the batch would still not be
possible to send, leading to the "Huh? No vq elem available" error.
Instead of checking available bytes, this patch optimistically pops
buffers from the queue and puts them back in case it runs out of
space and the batch needs to be dropped.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Message-id: 1490365490-4854-3-git-send-email-lprosek@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The AHCI emulation code supports 64-bit addressing and should advertise this
fact in the Host Capabilities register. Both Linux and Windows drivers test
this bit to decide if the upper 32 bits of various registers may be written
to, and at least some versions of Windows have a bug where DMA is attempted
with an address above 4GB but, in the absence of HOST_CAP_64, the upper 32
bits are left unititialized which leads to a memory corruption.
[Maintainer edit:
This fixes https://bugzilla.redhat.com/show_bug.cgi?id=1411105,
which affects Windows Server 2008 SP2 in some cases.]
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Message-id: 1484305370-6220-1-git-send-email-lprosek@redhat.com
[Amended commit message --js]
Signed-off-by: John Snow <jsnow@redhat.com>
ldl_p has a signed return type so assigning it to uint64_t implicitly
sign-extends the value. This results in devices with min_access_size = 8
seeing unexpected values passed to their write handlers.
Example: guest performs a 32-bit write of 0x80000000 to an mmio region
and the handler receives 0xFFFFFFFF80000000 in its value argument.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Message-Id: <1485440557-10384-1-git-send-email-lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Very simple loop optimization with a significant performance impact.
Microbenchmark results, modern x86-64:
buffer size | speed up
------------+---------
1500 | 1.7x
64 | 1.5x
8 | 1.15x
Microbenchmark results, POWER7:
buffer size | speed up
------------+---------
1500 | 5x
64 | 3.3x
8 | 1.13x
There is a lot of room for further improvement at the expense of
code complexity - aligned multibyte reads, LE/BE considerations,
architecture-specific optimizations, etc. This patch still keeps
things simple and readable.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Dmitry Fleytman <dmitry@daynix.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
The function does not fully initialize the returned VirtQueueElement and should
be used only internally from the virtio module.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The function undoes the effect of virtqueue_pop and doesn't do anything
destructive or irreversible so virtqueue_unpop is a more fitting name.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Unused function declarations were found using a simple gcc plugin and
manually verified by grepping the sources.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The statistics virtqueue is not migrated properly because virtio-balloon
does not include s->stats_vq_elem in the migration stream.
After migration the statistics virtqueue hangs because the host never
completes the last element (s->stats_vq_elem is NULL on the destination
QEMU). Therefore the guest never submits new elements and the virtqueue
is hung.
Instead of changing the migration stream format in an incompatible way,
detect the migration case and rewind the virtqueue so the last element
can be completed.
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Roman Kagan <rkagan@virtuozzo.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Suggested-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The one pending element is being freed but not discarded on device
reset, which causes svq->inuse to creep up, eventually hitting the
"Virtqueue size exceeded" error.
Properly discarding the element on device reset makes sure that its
buffers are unmapped and the inuse counter stays balanced.
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Roman Kagan <rkagan@virtuozzo.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
VIRTIO_INPUT_CFG_ABS_INFO was not implemented for pass-through input
devices. This patch follows the existing design and pre-fetches the
config for all absolute axes using EVIOCGABS at realize time.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Message-id: 1460558603-18331-1-git-send-email-lprosek@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The write path for pass-through devices, commonly used for controlling
keyboard LEDs via EV_LED, was not implemented. This commit adds the
necessary plumbing to connect the status virtio queue to the host evdev
file descriptor.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Message-id: 1459511146-12060-1-git-send-email-lprosek@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
KEY_PAUSE is flat out missing. KEY_SYSRQ already has a keycode
assigned but it's not what I'm seeing on my system. The mapping
doesn't appear to have to be unique so both keycodes now map to
KEY_SYSRQ which is what the "Keyboard PrintScreen", HID usage ID
0x46, translates to.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Message-id: 1459343240-19483-1-git-send-email-lprosek@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The segfault here is triggered by the driver notifying the stats queue
twice after adding a buffer to it. This effectively resets stats_vq_elem
back to NULL and QEMU crashes on the next stats timer tick in
balloon_stats_poll_cb.
This is a regression introduced in 51b19ebe43, although admittedly
the device assumed too much about the stats queue protocol even before
that commit. This commit adds a few more checks and ensures that the one
stats buffer gets deallocated on device reset.
Cc: qemu-stable@nongnu.org
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Requests are now created in the RngBackend parent class and the
code path is shared by both rng-egd and rng-random.
This commit fixes the rng-random implementation which processed
only one request at a time and simply discarded all but the most
recent one. In the guest this manifested as delayed completion
of reads from virtio-rng, i.e. a read was completed only after
another read was issued.
By switching rng-random to use the same request queue as rng-egd,
the unsafe stack-based allocation of the entropy buffer is
eliminated and replaced with g_malloc.
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Message-Id: <1456994238-9585-5-git-send-email-lprosek@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>