Numonyx/Micron flashes [1] do not use one fixed dummy-phase width for all
fast-read commands. The volatile configuration register stores a number
of dummy clock cycles, and QEMU must convert that value to the number of
SSI bytes consumed by the flash model.
Keep the existing default: 10 dummy clocks in Quad I/O mode and 8 dummy
clocks otherwise. In Quad I/O and Dual I/O protocol modes, all command
phases are transferred on 4 or 2 lines, so the dummy clock count still
needs to be scaled by that bus width.
Standard SPI, also called extended SPI in the Micron datasheet, is more
subtle. Quad Output Fast Read (6Bh) and Dual Output Fast Read (3Bh) keep
the opcode and address phases on DQ0; their dummy phase is just a clock
gap before data is returned on four or two output lines. Do not scale the
dummy count for those output-only commands. Only Quad I/O Fast Read
(EBh) and Dual I/O Fast Read (BBh) transfer the address and dummy phases
on the 4-bit or 2-bit bus, so keep scaling those commands.
[1] https://docs.rs-online.com/cad7/0900766b8121bd3c.pdf
Fixes: 23af268566 ("hw/block/m25p80: Fix Numonyx fast read dummy cycle count")
Signed-off-by: Bin Meng <bin.meng@processmission.com>
Tested-by: Cédric Le Goater <clg@redhat.com>
Message-ID: <20260707083431.219671-3-bin.meng@processmission.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@oss.qualcomm.com>
The m25p80 model uses s->needed_bytes to track how many bytes a
controller must send after an opcode before the flash model can enter
the data phase. For address-bearing commands this includes the address
bytes. For fast-read commands it also includes the dummy phase.
The tricky part is that flash datasheets describe the dummy phase in
clock cycles, while the QEMU SSI interface advances the flash model one
transferred byte at a time. The dummy clock count therefore has to be
converted to the number of SSI bytes that the controller will actually
emit.
Some controllers have drivers that push these dummy bytes into a FIFO.
Other controllers are programmed with a dummy-cycle count and generate
the clocks themselves. The flash model still has to use the same byte
count that a FIFO-style controller or the Linux spi-mem layer would use,
otherwise the model waits too long and drops the first data bytes.
Let's fix the inconsistency from the flash side first. We start from an
easy one, the Winbond flashes.
Per the Windbond W25Q256JV datasheet [1] instruction set table
(chapter 8.1.2, 8.1.3, 8.1.4, 8.1.5), fix the wrong number of
dummy bytes needed for fast read commands.
[1] https://www.winbond.com/resource-files/w25q256jv%20spi%20revb%2009202016.pdf
Fixes: fe84770528 ("m25p80: Fix QIOR/DIOR handling for Winbond")
Fixes: 3830c7a460 ("m25p80: Fix WINBOND fast read command handling")
Fixes: cf6f1efe0b ("m25p80: Fast read commands family changes")
Signed-off-by: Bin Meng <bin.meng@processmission.com>
Tested-by: Cédric Le Goater <clg@redhat.com>
Message-ID: <20260707083431.219671-2-bin.meng@processmission.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@oss.qualcomm.com>
The virtio specification is not completely clear about seg_max and its
relationship with queue_size. Some drivers (for example, the modern
Linux kernel driver) rely on seg_max to set the maximum number of
segments used in a request. If seg_max is set larger than queue_size,
such a driver might overwhelm a virtqueue by trying to send more
segments than it can handle. As a result, it either hangs or faults.
One might argue that it is the vhost-user server's responsibility to set
a valid seg_max value. However, due to the issue described in the
previous paragraph, this value should generally depend on queue_size.
That's why it may be necessary to control it on QEMU's side.
This patch adds the seg-max-adjust flag. A flag with the same name
already exists for virtio-blk (and it exists to solve the same problem,
except that here we have a vhost-user server to consult).
If seg-max-adjust is set, the final seg_max is the minimum of the value
provided by the vhost-user server and (queue_size - 2). It is not
enabled by default.
Signed-off-by: Sergei Heifetz <heifetz@yandex-team.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-ID: <20260401230548.136541-1-heifetz@yandex-team.com>
pci, vhost, virtio, iommu: features, fixes, cleanups
intel_iommu:
PASID support for passthrough
some properties renamed
virtio-rtc:
new device
acpi:
watchdog (x86 q35)
COM irqs are now shared
vhost-user:
vhost-user passes GPA not HVA now
vhost SHMEM_MAP/UNMAP support
vhost-vdpa:
svq IN_ORDER support
amd_iommu:
IOMMU XT interrupt support
command buffer fixes
cxl:
PPR support
performant path for non-interleaved cases
vhost-scsi:
build fix for older kernel headers
fixes, cleanups all over the place
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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* tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu: (106 commits)
hw/scsi/vhost-scsi: fix build with older kernel headers
tests/qtest: add 8-byte MMIO access sweep for intel-iommu
intel_iommu: fix guest-triggerable abort on oversized MMIO access
hw/cxl: Add a performant (and correct) path for the non interleaved cases
hw/cxl: Allow cxl_cfmws_find_device() to filter on whether interleaved paths are accepted
hw/cxl/events: Fix handling of component ID in event records generation to not assume it is a string
hw/cxl: Add fixes in Post Package Repair (PPR)
hw/cxl: Fix handling of component ID to not assume it is a string
vhost-user.rst: fix typo
vhost-user-device: Add shared memory BAR
qmp: add shmem feature map
vhost_user.rst: Add GET_SHMEM_CONFIG message
vhost_user: Add frontend get_shmem_config command
vhost_user.rst: Add SHMEM_MAP/_UNMAP to spec
vhost_user.rst: Align VhostUserMsg excerpt members
vhost-user: Add VirtIO Shared Memory map request
tests: acpi: x86/q35: update expected WDAT blob
tests: acpi: x86/q35: add WDAT table test case
tests: acpi: x86/q35: whitelist new WDAT table
x86: q35: generate WDAT ACPI table
...
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Check that the iovec containing struct virtio_scsi_inhdr is large enough
before storing an error value there.
Feifan Qian <bea1e@proton.me> pointed out that this can be used to
corrupt heap memory when the descriptor uses an MMIO address and a
length of 1, forcing QEMU to allocate a 1-byte heap bounce buffer.
virtio_stl_p() stores 4 bytes and therefore corrupts whatever is beyond
the bounce buffer.
Fixes: CVE-2026-48914
Fixes: f34e73cd69 ("virtio-blk: report non-zero status when failing SG_IO requests")
Reported-by: Feifan Qian <bea1e@proton.me>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20260526154957.1741622-1-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Commit bc85aae420 ("vhost-user: return failure if backend crash when
live migration") refactored the set_guest_notifiers error handling but
introduced two regressions across multiple vhost devices.
By moving the function call directly into the if condition, the
subsequent error_report prints the stale ret variable instead of the
actual error code. Additionally, the refactoring hardcoded a return
value of -1 rather than propagating the true error status to the
caller.
Fix these issues by storing the set_guest_notifiers result in a local
err variable.
Fixes: bc85aae420 ("vhost-user: return failure if backend crash when live migration")
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260315231047.310029-1-visitorckw@gmail.com>
vhost_user_blk_get_features() unconditionally advertises
VIRTIO_BLK_F_SIZE_MAX regardless of what the backend reports in
its config. The built-in QSD vhost-user-blk backend sets
size_max=0, creating a contradictory state where the feature bit
tells the guest that size_max is valid but the value is zero.
The in-process virtio-blk device does not advertise
VIRTIO_BLK_F_SIZE_MAX (it also sets size_max=0 in config), so
guests never see this contradiction with native virtio-blk.
Linux tolerates size_max=0 because blk_validate_limits() silently
corrects max_segment_size=0 to BLK_MAX_SEGMENT_SIZE (65536).
Windows viostor, however, trusts the feature bit and uses the raw
size_max=0 in its scatter-gather calculations, producing
zero-length segments that hang I/O. The disk appears empty to
Windows (no GPT, no partitions), causing INACCESSIBLE_BOOT_DEVICE.
Stop force-adding VIRTIO_BLK_F_SIZE_MAX in the frontend. The
feature remains in user_feature_bits[], so backends that properly
advertise it with a valid config value will still work.
Signed-off-by: Max Makarov <maxpain@linux.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260331134721.96047-1-maxpain@linux.com>
This field is mostly unused and sometimes confusing. We even have
a TODO-like comment to drop it, the comment is removed in this commit.
The field is used to held VHOST_USER_F_PROTOCOL_FEATURES for vhost-user
and/or VHOST_NET_F_VIRTIO_NET_HDR for vhost-net (which may be
vhost-user-net). But we can simply recalculate these two flags in place
from hdev->features, and from net-client for VHOST_NET_F_VIRTIO_NET_HDR.
Note: removing field from x-query-virtio-status result is incompatible
change. We can do it because the command is unstable.
Cc: devel@lists.libvirt.org
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
Acked-by: Raphael Norwitz <raphael.s.norwitz@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260420200339.708640-3-vsementsov@yandex-team.ru>
If params is NULL, xen_block_drive_create calls xen_block_drive_destroy
with drive == NULL.
Reported-by: Siteshwar Vashisht <svashisht@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
During inter-host migration, waiting for disk requests to be drained
in the vhost-user backend can incur significant downtime.
This can be avoided if QEMU migrates the inflight region in
vhost-user-blk.
Thus, during the qemu migration, with feature flag the vhost-user
back-end can immediately stop vrings, so all in-flight requests will be
migrated to another host.
Signed-off-by: Alexandr Moshkov <dtalexundeer@yandex-team.ru>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.s.norwitz@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20260115081103.655749-6-dtalexundeer@yandex-team.ru>
This patch allows stats-intervals to be used for storage
devices with the -device option. It accepts a list of interval
lengths in JSON format.
It configures and collects the stats in the BlockBackend layer
through the storage device that consumes the BlockBackend.
Signed-off-by: Chandan Somani <csomani@redhat.com>
Message-ID: <20251003220039.1336663-1-csomani@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The difference between these two functions:
- virtio_notify() uses the interrupt code path (MSI or classic IRQs)
- virtio_notify_irqfd() uses guest notifiers (irqfds)
virtio_notify() can only be called with the BQL held because the
interrupt code path requires the BQL. Device models use
virtio_notify_irqfd() from IOThreads since the BQL is not held.
The two functions can be unified by pushing down the if
(qemu_in_iothread()) check from virtio-blk and virtio-scsi into core
virtio code. This is in preparation for the next commit that will add
irqfd support to virtio_notify_config() and where it's unattractive to
introduce another irqfd-only API for device model callers.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-ID: <20250922220149.498967-3-stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
If we have a server running disk requests that is for whatever reason
hanging or not able to process any more IO requests but still has some
in-flight requests previously issued by the guest OS, QEMU will still
try to drain the vring before shutting down even if it was explicitly
asked to do a "force shutdown" via SIGTERM or QMP quit. This is not
useful since the guest is no longer running at this point since it was
killed by QEMU earlier in the process. At this point, we don't care
about whatever in-flight IO it might have pending, we just want QEMU
to shut down.
Add an option called "skip-get-vring-base-on-force-shutdown" to allow
SIGTERM/QMP quit() to actually act like a "force shutdown" at least
for vhost-user-blk devices since those require the drain operation
to shut down gracefully unlike, for example, network devices.
Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
Message-Id: <20250609212547.2859224-4-d-tatianin@yandex-team.ru>
Acked-by: Raphael Norwitz <raphael@enfabrica.net>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The nand.c device (TYPE_NAND) is an emulation of a NAND flash memory
chip which was used by the old OMAP boards. No current QEMU board
uses it, and although techically "-device nand,chip-id=0x6b" doesn't
error out, it's not possible to usefully use it from the command
line because the only interface it has is via calling C functions
like nand_setpins() and nand_setio().
The "config OMAP" stanza (used only by the SX1 board) is the only
thing that does "select NAND" to compile in this code, but the SX1
board doesn't actually use the NAND device.
Remove the NAND device code entirely; this is effectively leftover
cleanup from when we dropped the PXA boards and the OMAP boards
other than the sx1.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20250522142859.3122389-1-peter.maydell@linaro.org
Live migration should be terminated if the vhost-user backend crashes
before the migration completes.
Specifically, since the vhost device will be stopped when VM is stopped
before the end of the live migration, in current implementation if the
backend crashes, vhost-user device set_status() won't return failure,
live migration won't perceive the disconnection between QEMU and the
backend.
When the VM is migrated to the destination, the inflight IO will be
resubmitted, and if the IO was completed out of order before, it will
cause IO error.
To fix this issue:
1. Add the return value to set_status() for VirtioDeviceClass.
a. For the vhost-user device, return failure when the backend crashes.
b. For other virtio devices, always return 0.
2. Return failure if vhost_dev_stop() failed for vhost-user device.
If QEMU loses connection with the vhost-user backend, virtio set_status()
can return failure to the upper layer, migration_completion() can handle
the error, terminate the live migration, and restore the VM, so that
inflight IO can be completed normally.
Signed-off-by: Haoqian He <haoqian.he@smartx.com>
Message-Id: <20250416024729.3289157-4-haoqian.he@smartx.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch adds the new VM state change cb type `VMChangeStateHandlerWithRet`,
which has return value for `VMChangeStateEntry`.
Thus, we can register a new VM state change cb with return value for device.
Note that `VMChangeStateHandler` and `VMChangeStateHandlerWithRet` are mutually
exclusive and cannot be provided at the same time.
This patch is the pre patch for 'vhost-user: return failure if backend crashes
when live migration', which makes the live migration aware of the loss of
connection with the vhost-user backend and aborts the live migration.
Virtio device will use VMChangeStateHandlerWithRet.
Signed-off-by: Haoqian He <haoqian.he@smartx.com>
Message-Id: <20250416024729.3289157-2-haoqian.he@smartx.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Convert the existing includes with
sed -i ,exec/memory.h,system/memory.h,g
Move the include within cpu-all.h into a !CONFIG_USER_ONLY block.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
During normal migration, new QEMU creates and initializes memory regions,
then loads the preserved contents of the region from vmstate.
During CPR, memory regions are preserved in place, then the realize
method initializes the regions contents, losing the old contents. To
fix, skip the re-init during CPR.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Message-ID: <1741380954-341079-3-git-send-email-steven.sistare@oracle.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Use noun_verb() function naming instead of verb_noun() because the
former is the most common naming style for APIs. The next commit will
move these functions into a header file so that virtio-scsi can call
them.
Shorten iothread_vq_mapping_apply()'s iothread_vq_mapping_list argument
to just "list" like in the other functions.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20250311132616.1049687-10-stefanha@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
PropertyInfo member @name becomes ObjectProperty member @type, while
Property member @name becomes ObjectProperty member @name. Rename the
former.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20250227085601.4140852-4-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
[One missed instance of @type fixed]
Apple has its own virtio-blk PCI device ID where it deviates from the
official virtio-pci spec slightly: It puts a new "apple type"
field at a static offset in config space and introduces a new barrier
command.
This patch first creates a mechanism for virtio-blk downstream classes to
handle unknown commands. It then creates such a downstream class and a new
vmapple-virtio-blk-pci class which support the additional apple type config
identifier as well as the barrier command.
The 'aux' or 'root' device type are selected using the 'variant' property.
Signed-off-by: Alexander Graf <graf@amazon.com>
Signed-off-by: Phil Dennis-Jordan <phil@philjordan.eu>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Tested-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-ID: <20241223221645.29911-13-phil@philjordan.eu>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
The general expectation is that header files should follow the same
file/path naming scheme as the corresponding source file. There are
various historical exceptions to this practice in QEMU, with one of
the most notable being the include/qapi/qmp/ directory. Most of the
headers there correspond to source files in qobject/.
This patch corrects most of that inconsistency by creating
include/qobject/ and moving the headers for qobject/ there.
This also fixes MAINTAINERS for include/qapi/qmp/dispatch.h:
scripts/get_maintainer.pl now reports "QAPI" instead of "No
maintainers found".
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com> #s390x
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20241118151235.2665921-2-armbru@redhat.com>
[Rebased]
