Patch 06b1297017 ("virtio-net: fix network stall under load")
added double-check to test whether the available buffer size
can satisfy the request or not, in case the guest has added
some buffers to the avail ring simultaneously after the first
check. It will be lucky if the available buffer size becomes
okay after the double-check, then the host can send the packet
to the guest. If the buffer size still can't satisfy the request,
even if the guest has added some buffers, viritio-net would
stall at the host side forever.
The patch enables notification and checks whether the guest has
added some buffers since last check of available buffers when
the available buffers are insufficient. If no buffer is added,
return false, else recheck the available buffers in the loop.
If the available buffers are sufficient, disable notification
and return true.
Changes:
1. Change the return type of virtqueue_get_avail_bytes() from void
to int, it returns an opaque that represents the shadow_avail_idx
of the virtqueue on success, else -1 on error.
2. Add a new API: virtio_queue_enable_notification_and_check(),
it takes an opaque as input arg which is returned from
virtqueue_get_avail_bytes(). It enables notification firstly,
then checks whether the guest has added some buffers since
last check of available buffers or not by virtio_queue_poll(),
return ture if yes.
The patch also reverts patch "06b1297017".
The case below can reproduce the stall.
Guest 0
+--------+
| iperf |
---------------> | server |
Host | +--------+
+--------+ | ...
| iperf |----
| client |---- Guest n
+--------+ | +--------+
| | iperf |
---------------> | server |
+--------+
Boot many guests from qemu with virtio network:
qemu ... -netdev tap,id=net_x \
-device virtio-net-pci-non-transitional,\
iommu_platform=on,mac=xx:xx:xx:xx:xx:xx,netdev=net_x
Each guest acts as iperf server with commands below:
iperf3 -s -D -i 10 -p 8001
iperf3 -s -D -i 10 -p 8002
The host as iperf client:
iperf3 -c guest_IP -p 8001 -i 30 -w 256k -P 20 -t 40000
iperf3 -c guest_IP -p 8002 -i 30 -w 256k -P 20 -t 40000
After some time, the host loses connection to the guest,
the guest can send packet to the host, but can't receive
packet from the host.
It's more likely to happen if SWIOTLB is enabled in the guest,
allocating and freeing bounce buffer takes some CPU ticks,
copying from/to bounce buffer takes more CPU ticks, compared
with that there is no bounce buffer in the guest.
Once the rate of producing packets from the host approximates
the rate of receiveing packets in the guest, the guest would
loop in NAPI.
receive packets ---
| |
v |
free buf virtnet_poll
| |
v |
add buf to avail ring ---
|
| need kick the host?
| NAPI continues
v
receive packets ---
| |
v |
free buf virtnet_poll
| |
v |
add buf to avail ring ---
|
v
... ...
On the other hand, the host fetches free buf from avail
ring, if the buf in the avail ring is not enough, the
host notifies the guest the event by writing the avail
idx read from avail ring to the event idx of used ring,
then the host goes to sleep, waiting for the kick signal
from the guest.
Once the guest finds the host is waiting for kick singal
(in virtqueue_kick_prepare_split()), it kicks the host.
The host may stall forever at the sequences below:
Host Guest
------------ -----------
fetch buf, send packet receive packet ---
... ... |
fetch buf, send packet add buf |
... add buf virtnet_poll
buf not enough avail idx-> add buf |
read avail idx add buf |
add buf ---
receive packet ---
write event idx ... |
wait for kick add buf virtnet_poll
... |
---
no more packet, exit NAPI
In the first loop of NAPI above, indicated in the range of
virtnet_poll above, the host is sending packets while the
guest is receiving packets and adding buffers.
step 1: The buf is not enough, for example, a big packet
needs 5 buf, but the available buf count is 3.
The host read current avail idx.
step 2: The guest adds some buf, then checks whether the
host is waiting for kick signal, not at this time.
The used ring is not empty, the guest continues
the second loop of NAPI.
step 3: The host writes the avail idx read from avail
ring to used ring as event idx via
virtio_queue_set_notification(q->rx_vq, 1).
step 4: At the end of the second loop of NAPI, recheck
whether kick is needed, as the event idx in the
used ring written by the host is beyound the
range of kick condition, the guest will not
send kick signal to the host.
Fixes: 06b1297017 ("virtio-net: fix network stall under load")
Cc: qemu-stable@nongnu.org
Signed-off-by: Wencheng Yang <east.moutain.yang@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
(cherry picked from commit f937309fbd)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
(Mjt: context fixup in include/hw/virtio/virtio.h)
The unrealize functions of the various vhost-user devices are
calling the corresponding vhost_*_set_status() functions with a
status of 0 to shut down the device correctly.
Now these vhost_*_set_status() functions all follow this scheme:
bool should_start = virtio_device_should_start(vdev, status);
if (vhost_dev_is_started(&vvc->vhost_dev) == should_start) {
return;
}
if (should_start) {
/* ... do the initialization stuff ... */
} else {
/* ... do the cleanup stuff ... */
}
The problem here is virtio_device_should_start(vdev, 0) currently
always returns "true" since it internally only looks at vdev->started
instead of looking at the "status" parameter. Thus once the device
got started once, virtio_device_should_start() always returns true
and thus the vhost_*_set_status() functions return early, without
ever doing any clean-up when being called with status == 0. This
causes e.g. problems when trying to hot-plug and hot-unplug a vhost
user devices multiple times since the de-initialization step is
completely skipped during the unplug operation.
This bug has been introduced in commit 9f6bcfd99f ("hw/virtio: move
vm_running check to virtio_device_started") which replaced
should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
with
should_start = virtio_device_started(vdev, status);
which later got replaced by virtio_device_should_start(). This blocked
the possibility to set should_start to false in case the status flag
VIRTIO_CONFIG_S_DRIVER_OK was not set.
Fix it by adjusting the virtio_device_should_start() function to
only consider the status flag instead of vdev->started. Since this
function is only used in the various vhost_*_set_status() functions
for exactly the same purpose, it should be fine to fix it in this
central place there without any risk to change the behavior of other
code.
Fixes: 9f6bcfd99f ("hw/virtio: move vm_running check to virtio_device_started")
Buglink: https://issues.redhat.com/browse/RHEL-40708
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20240618121958.88673-1-thuth@redhat.com>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit d72479b117)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
spapr_irq_init currently uses existing macro SPAPR_XIRQ_BASE to refer to
the range of CPU IPIs during initialization of nr-irqs property.
It is more appropriate to have its own define which can be further
reused as appropriate for correct interpretation.
Suggested-by: Cedric Le Goater <clg@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Kowshik Jois <kowsjois@linux.ibm.com>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
(cherry picked from commit 2df5c1f5b0)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Introduce virtio_bh_new_guarded(), similar to qemu_bh_new_guarded()
but using the transport memory guard, instead of the device one
(there can only be one virtio device per virtio bus).
Inspired-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20240409105537.18308-2-philmd@linaro.org>
(cherry picked from commit ec0504b989)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The current handling of invalid virtqueue elements inside the TX/RX virt
queue handlers is wrong.
They are added in a per-stream invalid queue to be processed after the
handler is done examining each message, but the invalid message might
not be specifying any stream_id; which means it's invalid to add it to
any stream->invalid queue since stream could be NULL at this point.
This commit moves the invalid queue to the VirtIOSound struct which
guarantees there will always be a valid temporary place to store them
inside the tx/rx handlers. The queue will be emptied before the handler
returns, so the queue must be empty at any other point of the device's
lifetime.
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-Id: <virtio-snd-rewrite-invalid-tx-rx-message-handling-v1.manos.pitsidianakis@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit 731655f87f)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Calling job_pause_point() while holding the graph reader lock
potentially results in a deadlock: bdrv_graph_wrlock() first drains
everything, including the mirror job, which pauses it. The job is only
unpaused at the end of the drain section, which is when the graph writer
lock has been successfully taken. However, if the job happens to be
paused at a pause point where it still holds the reader lock, the writer
lock can't be taken as long as the job is still paused.
Mark job_pause_point() as GRAPH_UNLOCKED and fix mirror accordingly.
Cc: qemu-stable@nongnu.org
Buglink: https://issues.redhat.com/browse/RHEL-28125
Fixes: 004915a96a ("block: Protect bs->backing with graph_lock")
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20240313153000.33121-1-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit ae5a40e858)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The payload size returned by command VIRTIO_SND_R_PCM_INFO is
wrong. The code in process_cmd() assumes that all commands
return only a virtio_snd_hdr payload, but some commands like
VIRTIO_SND_R_PCM_INFO may return an additional payload.
Add a zero initialized payload_size variable to struct
virtio_snd_ctrl_command to allow for additional payloads.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <20240218083351.8524-1-vr_qemu@t-online.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit 633487df8d)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The sun4v RTC device model added under commit a0e893039c in 2016
was unfortunately added with a license of GPL-v3-or-later, which is
not compatible with other QEMU code which has a GPL-v2-only license.
Relicense the code in the .c and the .h file to GPL-v2-or-later,
to make it compatible with the rest of QEMU.
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini (for Red Hat) <pbonzini@redhat.com>
Signed-off-by: Artyom Tarasenko <atar4qemu@gmail.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20240223161300.938542-1-peter.maydell@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
(cherry picked from commit fd7f95f23d)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
In the current mdev_reg_read() implementation, it consistently returns
that the Media Status is Ready (01b). This was fine until commit
25a52959f9 ("hw/cxl: Add support for device sanitation") because the
media was presumed to be ready.
However, as per the CXL 3.0 spec "8.2.9.8.5.1 Sanitize (Opcode 4400h)",
during sanitation, the Media State should be set to Disabled (11b). The
mentioned commit correctly sets it to Disabled, but mdev_reg_read()
still returns Media Status as Ready.
To address this, update mdev_reg_read() to read register values instead
of returning dummy values.
Note that __toggle_media() managed to not only write something
that no one read, it did it to the wrong register storage and
so changed the reported mailbox size which was definitely not
the intent. That gets fixed as a side effect of allocating
separate state storage for this register.
Fixes: commit 25a52959f9 ("hw/cxl: Add support for device sanitation")
Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20240126120132.24248-7-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit f7509f462c)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
We need values 0-3 for TCG_TYPE_I128 on 32-bit hosts.
Cc: qemu-stable@nongnu.org
Fixes: 43eef72f41 ("tcg: Add temp allocation for TCGv_i128")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2159
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Tested-by: Michael Tokarev <mjt@tls.msk.ru>
(cherry picked from commit c0e688153f)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
During drain, we do not care about virtqueue notifications, which is why
we remove the handlers on it. When removing those handlers, whether vq
notifications are enabled or not depends on whether we were in polling
mode or not; if not, they are enabled (by default); if so, they have
been disabled by the io_poll_start callback.
Because we do not care about those notifications after removing the
handlers, this is fine. However, we have to explicitly ensure they are
enabled when re-attaching the handlers, so we will resume receiving
notifications. We do this in virtio_queue_aio_attach_host_notifier*().
If such a function is called while we are in a polling section,
attaching the notifiers will then invoke the io_poll_start callback,
re-disabling notifications.
Because we will always miss virtqueue updates in the drained section, we
also need to poll the virtqueue once after attaching the notifiers.
Buglink: https://issues.redhat.com/browse/RHEL-3934
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-ID: <20240202153158.788922-3-hreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 5bdbaebcce)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
ISM devices are sensitive to manipulation of the IOMMU, so the ISM device
needs to be reset before the vfio-pci device is reset (triggering a full
UNMAP). In order to ensure this occurs, trigger ISM device resets from
subsystem_reset before triggering the PCI bus reset (which will also
trigger vfio-pci reset). This only needs to be done for ISM devices
which were enabled for use by the guest.
Further, ensure that AIF is disabled as part of the reset event.
Fixes: ef1535901a ("s390x: do a subsystem reset before the unprotect on reboot")
Fixes: 03451953c7 ("s390x/pci: reset ISM passthrough devices on shutdown and system reset")
Reported-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Message-ID: <20240118185151.265329-4-mjrosato@linux.ibm.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
(cherry picked from commit 68c691ca99)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Use a flag to keep track of whether AIF is currently enabled. This can be
used to avoid enabling/disabling AIF multiple times as well as to determine
whether or not it should be disabled during reset processing.
Fixes: d0bc7091c2 ("s390x/pci: enable adapter event notification for interpreted devices")
Reported-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Message-ID: <20240118185151.265329-2-mjrosato@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
(cherry picked from commit 07b2c8e034)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
j is used while loading an ELF file to byteswap segments'
data. If data is larger than 2GB an overflow may happen.
So j should be elf_word.
This commit fixes a minor bug: it's unlikely anybody is trying to
load ELF files with 2GB+ segments for wrong-endianness targets,
but if they did, it wouldn't work correctly.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Cc: qemu-stable@nongnu.org
Fixes: 7ef295ea5b ("loader: Add data swap option to load-elf")
Signed-off-by: Anastasia Belova <abelova@astralinux.ru>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
(cherry picked from commit 410c2a4d75)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
GUEST_VIRTIO_MMIO_* was added in Xen 4.17, so only define them
for CONFIG_XEN_CTRL_INTERFACE_VERSIONs up to 4.16.
Reported-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
getloadavg is supported on Linux, BSDs, Solaris.
Following man page:
RETURN VALUE
If the load average was unobtainable, -1 is returned; otherwise,
the number of samples actually retrieved is returned.
accordingly, make stub for systems which don't support this function return -1
for consistency.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The vhost-user-blk export implement AioContext switches in its drain
implementation. This means that on drain_begin, it detaches the server
from its AioContext and on drain_end, attaches it again and schedules
the server->co_trip coroutine in the updated AioContext.
However, nothing guarantees that server->co_trip is even safe to be
scheduled. Not only is it unclear that the coroutine is actually in a
state where it can be reentered externally without causing problems, but
with two consecutive drains, it is possible that the scheduled coroutine
didn't have a chance yet to run and trying to schedule an already
scheduled coroutine a second time crashes with an assertion failure.
Following the model of NBD, this commit makes the vhost-user-blk export
shut down server->co_trip during drain so that resuming the export means
creating and scheduling a new coroutine, which is always safe.
There is one exception: If the drain call didn't poll (for example, this
happens in the context of bdrv_graph_wrlock()), then the coroutine
didn't have a chance to shut down. However, in this case the AioContext
can't have changed; changing the AioContext always involves a polling
drain. So in this case we can simply assert that the AioContext is
unchanged and just leave the coroutine running or wake it up if it has
yielded to wait for the AioContext to be attached again.
Fixes: e1054cd4aa
Fixes: https://issues.redhat.com/browse/RHEL-1708
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231127115755.22846-1-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The VIA integrated south bridge chips combine several functions and
allow routing their interrupts to any of the ISA IRQs also allowing
multiple sources to share the same ISA IRQ. E.g. pegasos2 firmware
configures everything to use IRQ 9 but amigaone routes them to
separate ISA IRQs so the current simplified routing does not work.
Bring back via_isa_set_irq() and change it to take the component that
wants to change an IRQ and keep track of interrupt status of each
source separately and do the mapping to ISA IRQ within the ISA bridge.
This may not handle cases when an ISA IRQ is controlled by devices
directly, not going through via_isa_set_irq() such as serial, parallel
or keyboard but these IRQs being conventionally fixed are not likely
to be change by guests or share with other devices so this does not
cause a problem in practice.
This reverts commit 4e5a20b6da.
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Message-ID: <1c3902d4166234bef0a476026441eaac3dd6cda5.1701035944.git.balaton@eik.bme.hu>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
It seems that the url changed a bit, and it triggers an error. Fix the URLs so
the documentation can be reached again.
Signed-off-by: Frederic Konrad <fkonrad@amd.com>
Reviewed-by: Francisco Iglesias <francisco.iglesias@amd.com>
Message-id: 20231124143505.1493184-3-fkonrad@amd.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The spips, qspips, and zynqmp-qspips share the same realize function
(xilinx_spips_realize) and initialize their io memory region with different
mmio_ops passed through the class. The size of the memory region is set to
the largest area (0x200 bytes for zynqmp-qspips) thus it is possible to write
out of s->regs[addr] in xilinx_spips_write for spips and qspips.
This fixes that wrong behavior.
Reviewed-by: Luc Michel <luc.michel@amd.com>
Signed-off-by: Frederic Konrad <fkonrad@amd.com>
Reviewed-by: Francisco Iglesias <francisco.iglesias@amd.com>
Message-id: 20231124143505.1493184-2-fkonrad@amd.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The VirtioPCIDeviceTypeInfo structure, added in commit a4ee4c8baa
("virtio: Helper for registering virtio device types") got extended
in commit 8ea90ee690 ("virtio: add class_size") with the @class_size
field. Do similarly with the @instance_finalize field.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20231121174051.63038-2-philmd@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This function reads the value of the PCI_CLASS_PROG register for PCI IDE
controllers and configures the PCI BARs and/or IDE ioports accordingly.
In the case where we switch to legacy mode, the PCI BARs are set to return zero
(as suggested in the "PCI IDE Controller" specification), the legacy IDE ioports
are enabled, and the PCI interrupt pin cleared to indicate legacy IRQ routing.
Conversely when we switch to native mode, the legacy IDE ioports are disabled
and the PCI interrupt pin set to indicate native IRQ routing. The contents of
the PCI BARs are unspecified, but this is not an issue since if a PCI IDE
controller has been switched to native mode then its BARs will need to be
programmed.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-ID: <20231116103355.588580-3-mark.cave-ayland@ilande.co.uk>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
These definitions are present in ioport.c which is currently only available when
CONFIG_IDE_ISA is enabled. Move them to the IDE core so that they can be made
available to PCI IDE controllers that support switching to legacy mode.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-ID: <20231116103355.588580-2-mark.cave-ayland@ilande.co.uk>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_graph_wrunlock() calls aio_poll(), which may run callbacks that
have a nested event loop. Nested event loops can depend on other
iothreads making progress, so in order to allow them to make progress it
must not hold the AioContext lock of another thread while calling
aio_poll().
This introduces a @bs parameter to bdrv_graph_wrunlock() whose
AioContext is temporarily dropped (which matches bdrv_graph_wrlock()),
and a bdrv_graph_wrunlock_ctx() that can be used if the BlockDriverState
doesn't necessarily exist any more when unlocking.
This also requires a change to bdrv_schedule_unref(), which was relying
on the incorrectly taken lock. It needs to take the lock itself now.
While this is a separate bug, it can't be fixed a separate patch because
otherwise the intermediate state would either deadlock or try to release
a lock that we don't even hold.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231115172012.112727-3-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[kwolf: Fixed up bdrv_schedule_unref()]
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* enable FEAT_RNG on Neoverse-N2
* hw/intc/arm_gicv3: ICC_PMR_EL1 high bits should be RAZ
* Fix SME FMOPA (16-bit), BFMOPA
* hw/core/machine: Constify MachineClass::valid_cpu_types[]
* stm32f* machines: Report error when user asks for wrong CPU type
* hw/arm/fsl-imx: Do not ignore Error argument
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Merge tag 'pull-target-arm-20231121' of https://git.linaro.org/people/pmaydell/qemu-arm into staging
target-arm queue:
* enable FEAT_RNG on Neoverse-N2
* hw/intc/arm_gicv3: ICC_PMR_EL1 high bits should be RAZ
* Fix SME FMOPA (16-bit), BFMOPA
* hw/core/machine: Constify MachineClass::valid_cpu_types[]
* stm32f* machines: Report error when user asks for wrong CPU type
* hw/arm/fsl-imx: Do not ignore Error argument
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# gpg: Signature made Tue 21 Nov 2023 05:21:42 EST
# gpg: using RSA key E1A5C593CD419DE28E8315CF3C2525ED14360CDE
# gpg: issuer "peter.maydell@linaro.org"
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" [full]
# gpg: aka "Peter Maydell <pmaydell@gmail.com>" [full]
# gpg: aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [full]
# gpg: aka "Peter Maydell <peter@archaic.org.uk>" [unknown]
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83 15CF 3C25 25ED 1436 0CDE
* tag 'pull-target-arm-20231121' of https://git.linaro.org/people/pmaydell/qemu-arm:
hw/arm/fsl-imx: Do not ignore Error argument
hw/arm/stm32f100: Report error when incorrect CPU is used
hw/arm/stm32f205: Report error when incorrect CPU is used
hw/arm/stm32f405: Report error when incorrect CPU is used
hw/core/machine: Constify MachineClass::valid_cpu_types[]
target/arm: Fix SME FMOPA (16-bit), BFMOPA
hw/intc/arm_gicv3: ICC_PMR_EL1 high bits should be RAZ
target/arm: enable FEAT_RNG on Neoverse-N2
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
In the minimal pixman API stub that is used when the real pixman
dependency is missing a NULL dereference happens when
virtio-gpu-rutabaga allocates a pixman image with bits = NULL and
rowstride_bytes = zero. A buffer of rowstride_bytes * height is
allocated which is NULL. However, in that scenario pixman calculates a
new stride value based on given width, height and format size.
This commit adds a helper function that performs the same logic as
pixman.
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20231121093840.2121195-1-manos.pitsidianakis@linaro.org>
Recently MemReentrancyGuard was added to DeviceState to record that the
device is engaging in I/O. The network device backend needs to update it
when delivering a packet to a device.
This implementation follows what bottom half does, but it does not add
a tracepoint for the case that the network device backend started
delivering a packet to a device which is already engaging in I/O. This
is because such reentrancy frequently happens for
qemu_flush_queued_packets() and is insignificant.
Fixes: CVE-2023-3019
Reported-by: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Acked-by: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Recently MemReentrancyGuard was added to DeviceState to record that the
device is engaging in I/O. The network device backend needs to update it
when delivering a packet to a device.
In preparation for such a change, add MemReentrancyGuard * as a
parameter of qemu_new_nic().
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Jason Wang <jasowang@redhat.com>
The 'stm32vldiscovery' machine ignores the CPU type requested by
the command line. This might confuse users, since the following
will create a machine with a Cortex-M3 CPU:
$ qemu-system-aarch64 -M stm32vldiscovery -cpu neoverse-n1
Set the MachineClass::valid_cpu_types field (introduced in commit
c9cf636d48 "machine: Add a valid_cpu_types property").
Remove the now unused MachineClass::default_cpu_type field.
We now get:
$ qemu-system-aarch64 -M stm32vldiscovery -cpu neoverse-n1
qemu-system-aarch64: Invalid CPU type: neoverse-n1-arm-cpu
The valid types are: cortex-m3-arm-cpu
Since the SoC family can only use Cortex-M3 CPUs, hard-code the
CPU type name at the SoC level, removing the QOM property
entirely.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Message-id: 20231117071704.35040-5-philmd@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The 'netduino2' machine ignores the CPU type requested by the
command line. This might confuse users, since the following will
create a machine with a Cortex-M3 CPU:
$ qemu-system-arm -M netduino2 -cpu cortex-a9
Set the MachineClass::valid_cpu_types field (introduced in commit
c9cf636d48 "machine: Add a valid_cpu_types property").
Remove the now unused MachineClass::default_cpu_type field.
We now get:
$ qemu-system-arm -M netduino2 -cpu cortex-a9
qemu-system-arm: Invalid CPU type: cortex-a9-arm-cpu
The valid types are: cortex-m3-arm-cpu
Since the SoC family can only use Cortex-M3 CPUs, hard-code the
CPU type name at the SoC level, removing the QOM property
entirely.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Message-id: 20231117071704.35040-4-philmd@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Both 'netduinoplus2' and 'olimex-stm32-h405' machines ignore the
CPU type requested by the command line. This might confuse users,
since the following will create a machine with a Cortex-M4 CPU:
$ qemu-system-aarch64 -M netduinoplus2 -cpu cortex-r5f
Set the MachineClass::valid_cpu_types field (introduced in commit
c9cf636d48 "machine: Add a valid_cpu_types property").
Remove the now unused MachineClass::default_cpu_type field.
We now get:
$ qemu-system-aarch64 -M netduinoplus2 -cpu cortex-r5f
qemu-system-aarch64: Invalid CPU type: cortex-r5f-arm-cpu
The valid types are: cortex-m4-arm-cpu
Since the SoC family can only use Cortex-M4 CPUs, hard-code the
CPU type name at the SoC level, removing the QOM property
entirely.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Message-id: 20231117071704.35040-3-philmd@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Constify MachineClass::valid_cpu_types[i], as suggested by Richard
Henderson.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20231117071704.35040-2-philmd@linaro.org
[PMD: Constify HPPA machines,
restrict valid_cpu_types to machine_class_init() handlers]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Fixes: bc4e68d362 "hw/ufs: Initial commit for emulated Universal-Flash-Storage"
Reviewed-by: Jeuk Kim <jeuk20.kim@samsung.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Fixes: 388d6b574e "hw/cxl: Use switch statements for read and write of cachemem registers"
Fixes: 3314efd276 "hw/cxl/mbox: Add Physical Switch Identify command."
Fixes: 004e3a93b8 "hw/cxl: Add tunneled command support to mailbox for switch cci."
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
In cpu_exec_step_atomic, we did not set CF_LAST_IO, which lead
to a loop with cpu_io_recompile.
But since 18a536f1f8 ("Always require can_do_io") we no longer
need a flag to indicate when the last insn should have can_do_io set,
so remove the flag entirely.
Reported-by: Clément Chigot <chigot@adacore.com>
Tested-by: Clément Chigot <chigot@adacore.com>
Reviewed-by: Claudio Fontana <cfontana@suse.de>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1961
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Some architectures (s390x) need to cleanup after a failed dump to be
able to continue to run the vm. Add a cleanup function pointer and
call it if it's set.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20231109120443.185979-3-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
When compiling QEMU with Clang 17 on a s390x, the compilation fails:
In file included from ../accel/tcg/cputlb.c:32:
In file included from /root/qemu/include/exec/helper-proto-common.h:10:
In file included from /root/qemu/include/qemu/atomic128.h:62:
/root/qemu/host/include/generic/host/atomic128-ldst.h:68:15: error:
__sync builtin operation MUST have natural alignment (consider using __
atomic). [-Werror,-Wsync-alignment]
68 | } while (!__sync_bool_compare_and_swap_16(ptr_align, old, new.i));
| ^
In file included from ../accel/tcg/cputlb.c:32:
In file included from /root/qemu/include/exec/helper-proto-common.h:10:
In file included from /root/qemu/include/qemu/atomic128.h:61:
/root/qemu/host/include/generic/host/atomic128-cas.h:36:11: error:
__sync builtin operation MUST have natural alignment (consider using __a
tomic). [-Werror,-Wsync-alignment]
36 | r.i = __sync_val_compare_and_swap_16(ptr_align, c.i, n.i);
| ^
2 errors generated.
It's arguably a bug in Clang since we already use __builtin_assume_aligned()
to tell the compiler that the pointer is properly aligned. But according to
https://github.com/llvm/llvm-project/issues/69146 it seems like the Clang
folks don't see an easy fix on their side and recommend to use a type
declared with __attribute__((aligned(16))) to work around this problem.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1934
Message-ID: <20231108085954.313071-1-thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Until now, array properties are actually implemented with a hack that
uses multiple properties on the QOM level: a static "foo-len" property
and after it is set, dynamically created "foo[i]" properties.
In external interfaces (-device on the command line and device_add in
QMP), this interface was broken by commit f3558b1b ('qdev: Base object
creation on QDict rather than QemuOpts') because QDicts are unordered
and therefore it could happen that QEMU tried to set the indexed
properties before setting the length, which fails and effectively makes
array properties inaccessible. In particular, this affects the 'ports'
property of the 'rocker' device, which used to be configured like this:
-device rocker,len-ports=2,ports[0]=dev0,ports[1]=dev1
This patch reworks the external interface so that instead of using a
separate top-level property for the length and for each element, we use
a single true array property that accepts a list value. In the external
interfaces, this is naturally expressed as a JSON list and makes array
properties accessible again. The new syntax looks like this:
-device '{"driver":"rocker","ports":["dev0","dev1"]}'
Creating an array property on the command line without using JSON format
is currently not possible. This could be fixed by switching from
QemuOpts to a keyval parser, which however requires consideration of the
compatibility implications.
All internal users of devices with array properties go through
qdev_prop_set_array() at this point, so updating it takes care of all of
them.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1090
Fixes: f3558b1b76
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231109174240.72376-12-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This function provides a default for properties that are accessed using
the list visitor interface. The default is always an empty list.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-ID: <20231109174240.72376-10-kwolf@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
- Graph locking part 6 (bs->file/backing)
- ahci: trigger either error IRQ or regular IRQ, not both
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Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging
Block layer patches
- Graph locking part 6 (bs->file/backing)
- ahci: trigger either error IRQ or regular IRQ, not both
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# gpg: Signature made Thu 09 Nov 2023 00:56:39 HKT
# gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg: issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6
* tag 'for-upstream' of https://repo.or.cz/qemu/kevin: (25 commits)
hw/ide/ahci: trigger either error IRQ or regular IRQ, not both
block: Protect bs->file with graph_lock
block: Take graph lock for most of .bdrv_open
vhdx: Take locks for accessing bs->file
qcow2: Take locks for accessing bs->file
block: Add missing GRAPH_RDLOCK annotations
block: Introduce bdrv_co_change_backing_file()
blkverify: Add locking for request_fn
block: Protect bs->backing with graph_lock
block: Mark bdrv_replace_node() GRAPH_WRLOCK
block: Mark bdrv_replace_node_common() GRAPH_WRLOCK
block: Inline bdrv_set_backing_noperm()
block: Mark bdrv_set_backing_hd_drained() GRAPH_WRLOCK
block: Mark bdrv_cow_child() and callers GRAPH_RDLOCK
block: Mark bdrv_filter_child() and callers GRAPH_RDLOCK
block: Mark bdrv_chain_contains() and callers GRAPH_RDLOCK
block: Mark bdrv_(un)freeze_backing_chain() and callers GRAPH_RDLOCK
block: Mark bdrv_skip_filters() and callers GRAPH_RDLOCK
block: Mark bdrv_skip_implicit_filters() and callers GRAPH_RDLOCK
block: Mark bdrv_filter_or_cow_bs() and callers GRAPH_RDLOCK
...
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>