aboutsummaryrefslogtreecommitdiff
path: root/hw/virtio/vhost-user.c
AgeCommit message (Collapse)Author
2023-03-07hw/virtio/vhost-user: avoid using unitialized errpAlbert Esteve
During protocol negotiation, when we the QEMU stub does not support a backend with F_CONFIG, it throws a warning and supresses the VHOST_USER_PROTOCOL_F_CONFIG bit. However, the warning uses warn_reportf_err macro and passes an unitialized errp pointer. However, the macro tries to edit the 'msg' member of the unitialized Error and segfaults. Instead, just use warn_report, which prints a warning message directly to the output. Fixes: 5653493 ("hw/virtio/vhost-user: don't suppress F_CONFIG when supported") Signed-off-by: Albert Esteve <aesteve@redhat.com> Message-Id: <20230302121719.9390-1-aesteve@redhat.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-03-02vhost-user: Adopt new backend namingMaxime Coquelin
The Vhost-user specification changed feature and request naming from _SLAVE_ to _BACKEND_. This patch adopts the new naming convention. Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com> Message-Id: <20230208203259.381326-4-maxime.coquelin@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-01-28Revert "vhost-user: Introduce nested event loop in vhost_user_read()"Greg Kurz
This reverts commit a7f523c7d114d445c5d83aecdba3efc038e5a692. The nested event loop is broken by design. It's only user was removed. Drop the code as well so that nobody ever tries to use it again. I had to fix a couple of trivial conflicts around return values because of 025faa872bcf ("vhost-user: stick to -errno error return convention"). Signed-off-by: Greg Kurz <groug@kaod.org> Message-Id: <20230119172424.478268-3-groug@kaod.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2023-01-28Revert "vhost-user: Monitor slave channel in vhost_user_read()"Greg Kurz
This reverts commit db8a3772e300c1a656331a92da0785d81667dc81. Motivation : this is breaking vhost-user with DPDK as reported in [0]. Received unexpected msg type. Expected 22 received 40 Fail to update device iotlb Received unexpected msg type. Expected 40 received 22 Received unexpected msg type. Expected 22 received 11 Fail to update device iotlb Received unexpected msg type. Expected 11 received 22 vhost VQ 1 ring restore failed: -71: Protocol error (71) Received unexpected msg type. Expected 22 received 11 Fail to update device iotlb Received unexpected msg type. Expected 11 received 22 vhost VQ 0 ring restore failed: -71: Protocol error (71) unable to start vhost net: 71: falling back on userspace virtio The failing sequence that leads to the first error is : - QEMU sends a VHOST_USER_GET_STATUS (40) request to DPDK on the master socket - QEMU starts a nested event loop in order to wait for the VHOST_USER_GET_STATUS response and to be able to process messages from the slave channel - DPDK sends a couple of legitimate IOTLB miss messages on the slave channel - QEMU processes each IOTLB request and sends VHOST_USER_IOTLB_MSG (22) updates on the master socket - QEMU assumes to receive a response for the latest VHOST_USER_IOTLB_MSG but it gets the response for the VHOST_USER_GET_STATUS instead The subsequent errors have the same root cause : the nested event loop breaks the order by design. It lures QEMU to expect responses to the latest message sent on the master socket to arrive first. Since this was only needed for DAX enablement which is still not merged upstream, just drop the code for now. A working solution will have to be merged later on. Likely protect the master socket with a mutex and service the slave channel with a separate thread, as discussed with Maxime in the mail thread below. [0] https://lore.kernel.org/qemu-devel/43145ede-89dc-280e-b953-6a2b436de395@redhat.com/ Reported-by: Yanghang Liu <yanghliu@redhat.com> Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2155173 Signed-off-by: Greg Kurz <groug@kaod.org> Message-Id: <20230119172424.478268-2-groug@kaod.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2023-01-28vhost-user: Skip unnecessary duplicated VHOST_USER_ADD/REM_MEM_REG requestsMinghao Yuan
The VHOST_USER_ADD/REM_MEM_REG requests should be categorized into non-vring specific messages, and should be sent only once. Signed-off-by: Minghao Yuan <yuanmh12@chinatelecom.cn> Message-Id: <20230123122119.194347-1-yuanmh12@chinatelecom.cn> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-01-27vhost-user: Correct a reference of TARGET_AARCH64Akihiko Odaki
Presumably TARGET_ARM_64 should be a mistake of TARGET_AARCH64. Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com> Message-Id: <20230109063130.81296-1-akihiko.odaki@daynix.com> Fixes: 27598393a2 ("Lift max memory slots limit imposed by vhost-user") Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-12-21vhost-user: send set log base message only onceYajun Wu
Vhost message VHOST_USER_SET_LOG_BASE is device wide. So only send it once with the first queue pair. Signed-off-by: Yajun Wu <yajunw@nvidia.com> Acked-by: Parav Pandit <parav@nvidia.com> Message-Id: <20221122051447.248462-1-yajunw@nvidia.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-12-14cleanup: Tweak and re-run return_directly.cocciMarkus Armbruster
Tweak the semantic patch to drop redundant parenthesis around the return expression. Coccinelle drops a comment in hw/rdma/vmw/pvrdma_cmd.c; restored manually. Coccinelle messes up vmdk_co_create(), not sure why. Change dropped, will be done manually in the next commit. Line breaks in target/avr/cpu.h and hw/rdma/vmw/pvrdma_cmd.c tidied up manually. Whitespace in tools/virtiofsd/fuse_lowlevel.c tidied up manually. checkpatch.pl complains "return of an errno should typically be -ve" two times for hw/9pfs/9p-synth.c. Preexisting, the patch merely makes it visible to checkpatch.pl. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20221122134917.1217307-2-armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-12-01hw/virtio: generalise CHR_EVENT_CLOSED handlingAlex Bennée
..and use for both virtio-user-blk and virtio-user-gpio. This avoids the circular close by deferring shutdown due to disconnection until a later point. virtio-user-blk already had this mechanism in place so generalise it as a vhost-user helper function and use for both blk and gpio devices. While we are at it we also fix up vhost-user-gpio to re-establish the event handler after close down so we can reconnect later. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Message-Id: <20221130112439.2527228-5-alex.bennee@linaro.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-11-07vhost-user: Support vhost_dev_startYajun Wu
The motivation of adding vhost-user vhost_dev_start support is to improve backend configuration speed and reduce live migration VM downtime. Today VQ configuration is issued one by one. For virtio net with multi-queue support, backend needs to update RSS (Receive side scaling) on every rx queue enable. Updating RSS is time-consuming (typical time like 7ms). Implement already defined vhost status and message in the vhost specification [1]. (a) VHOST_USER_PROTOCOL_F_STATUS (b) VHOST_USER_SET_STATUS (c) VHOST_USER_GET_STATUS Send message VHOST_USER_SET_STATUS with VIRTIO_CONFIG_S_DRIVER_OK for device start and reset(0) for device stop. On reception of the DRIVER_OK message, backend can apply the needed setting only once (instead of incremental) and also utilize parallelism on enabling queues. This improves QEMU's live migration downtime with vhost user backend implementation by great margin, specially for the large number of VQs of 64 from 800 msec to 250 msec. [1] https://qemu-project.gitlab.io/qemu/interop/vhost-user.html Signed-off-by: Yajun Wu <yajunw@nvidia.com> Acked-by: Parav Pandit <parav@nvidia.com> Message-Id: <20221017064452.1226514-3-yajunw@nvidia.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-11-07vhost-user: Fix out of order vring host notification handlingYajun Wu
vhost backend sends host notification for every VQ. If backend creates VQs in parallel, the VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG may arrive to QEMU in different order than incremental queue index order. For example VQ 1's message arrive earlier than VQ 0's: After alloc VhostUserHostNotifier for VQ 1. GPtrArray becomes [ nil, VQ1 pointer ] After alloc VhostUserHostNotifier for VQ 0. GPtrArray becomes [ VQ0 pointer, nil, VQ1 pointer ] This is wrong. fetch_notifier will return NULL for VQ 1 in vhost_user_get_vring_base, causes host notifier miss removal(leak). The fix is to remove current element from GPtrArray, make the right position for element to insert. Fixes: 503e355465 ("virtio/vhost-user: dynamically assign VhostUserHostNotifiers") Signed-off-by: Yajun Wu <yajunw@nvidia.com> Acked-by: Parav Pandit <parav@nvidia.com> Message-Id: <20221018023651.1359420-1-yajunw@nvidia.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-10-07hw/virtio: fix some coding style issuesAlex Bennée
Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Acked-by: Jason Wang <jasowang@redhat.com> Message-Id: <20220802095010.3330793-8-alex.bennee@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2022-10-07hw/virtio: incorporate backend features in featuresAlex Bennée
There are some extra bits used over a vhost-user connection which are hidden from the device itself. We need to set them here to ensure we enable things like the protocol extensions. Currently net/vhost-user.c has it's own inscrutable way of persisting this data but it really should live in the core vhost_user code. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20220726192150.2435175-7-alex.bennee@linaro.org> Message-Id: <20220802095010.3330793-2-alex.bennee@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2022-09-29vhost-user: Call qemu_socketpair() instead of socketpair()Guoyi Tu
As the close-on-exec flags is not set on the file descriptors returned by socketpair() at default, the fds will survive across exec' function. In the case that exec' function get invoked, such as the live-update feature which is been developing, it will cause fd leaks. To address this problem, we should call qemu_socketpair() to create an pair of connected sockets with the close-on-exec flag set. Signed-off-by: Guoyi Tu <tugy@chinatelecom.cn> Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <7002b12a5fb0a30cd878e14e07da61c36da72913.1661240709.git.tugy@chinatelecom.cn>
2022-08-17hw/virtio: fix vhost_user_read tracepointAlex Bennée
As reads happen in the callback we were never seeing them. We only really care about the header so move the tracepoint to when the header is complete. Fixes: 6ca6d8ee9d (hw/virtio: add vhost_user_[read|write] trace points) Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Acked-by: Jason Wang <jasowang@redhat.com> Message-Id: <20220728135503.1060062-5-alex.bennee@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-06-27vhost: add method vhost_set_vring_errKonstantin Khlebnikov
Kernel and user vhost may report virtqueue errors via eventfd. This is only reliable way to get notification about protocol error. Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Message-Id: <20220623161325.18813-2-vsementsov@yandex-team.ru> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Roman Kagan <rvkagan@yandex-team.ru>
2022-06-16virtio/vhost-user: Fix wrong vhost notifier GPtrArray sizeYajun Wu
In fetch_or_create_notifier, idx begins with 0. So the GPtrArray size should be idx + 1 and g_ptr_array_set_size should be called with idx + 1. This wrong GPtrArray size causes fetch_or_create_notifier return an invalid address. Passing this invalid pointer to vhost_user_host_notifier_remove causes assert fail: qemu/include/qemu/int128.h:27: int128_get64: Assertion `r == a' failed. shutting down, reason=crashed Backends like dpdk-vdpa which sends out vhost notifier requests almost always hit qemu crash. Fixes: 503e355465 ("virtio/vhost-user: dynamically assign VhostUserHostNotifiers") Signed-off-by: Yajun Wu <yajunw@nvidia.com> Acked-by: Parav Pandit <parav@nvidia.com> Change-Id: I87e0f7591ca9a59d210879b260704a2d9e9d6bcd Message-Id: <20220526034851.683258-1-yajunw@nvidia.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Eddie Dong <eddie.dong@intel.com>
2022-06-09hw/virtio/vhost-user: don't use uninitialized variableChangpeng Liu
Variable `vdev` in `struct vhost_dev` will not be ready until start the device, so let's not use it for the error output here. Fixes: 5653493 ("hw/virtio/vhost-user: don't suppress F_CONFIG when supported") Signed-off-by: Changpeng Liu <changpeng.liu@intel.com> Message-Id: <20220525125540.50979-1-changpeng.liu@intel.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Fixes: 5653493 ("hw/virtio/vhost-user: don't suppress F_CONFIG when supported") Signed-off-by: Changpeng Liu <changpeng.liu@intel.com> Fixes: 5653493 ("hw/virtio/vhost-user: don't suppress F_CONFIG when supported") Signed-off-by: Changpeng Liu <changpeng.liu@intel.com>
2022-05-16virtio/vhost-user: dynamically assign VhostUserHostNotifiersAlex Bennée
At a couple of hundred bytes per notifier allocating one for every potential queue is very wasteful as most devices only have a few queues. Instead of having this handled statically dynamically assign them and track in a GPtrArray. [AJB: it's hard to trigger the vhost notifiers code, I assume as it requires a KVM guest with appropriate backend] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20220321153037.3622127-14-alex.bennee@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-16hw/virtio/vhost-user: don't suppress F_CONFIG when supportedAlex Bennée
Previously we would silently suppress VHOST_USER_PROTOCOL_F_CONFIG during the protocol negotiation if the QEMU stub hadn't implemented the vhost_dev_config_notifier. However this isn't the only way we can handle config messages, the existing vdc->get/set_config can do this as well. Lightly re-factor the code to check for both potential methods and instead of silently squashing the feature error out. It is unlikely that a vhost-user backend expecting to handle CONFIG messages will behave correctly if they never get sent. Fixes: 1c3e5a2617 ("vhost-user: back SET/GET_CONFIG requests with a protocol feature") Cc: Maxime Coquelin <maxime.coquelin@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20220321153037.3622127-13-alex.bennee@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-16hw/virtio: add vhost_user_[read|write] trace pointsAlex Bennée
These are useful when trying to debug the initial vhost-user negotiation, especially when it hard to get logging from the low level library on the other side. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20220321153037.3622127-4-alex.bennee@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2022-05-05vhost-user: Use correct macro name TARGET_PPC64Murilo Opsfelder Araujo
The correct name of the macro is TARGET_PPC64. Fixes: 27598393a232 ("Lift max memory slots limit imposed by vhost-user") Reported-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com> Cc: Raphael Norwitz <raphael.norwitz@nutanix.com> Cc: Peter Turschmid <peter.turschm@nutanix.com> Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Message-Id: <20220503180108.34506-1-muriloo@linux.ibm.com> Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2022-05-04vhost-user: Don't pass file descriptor for VHOST_USER_REM_MEM_REGKevin Wolf
The spec clarifies now that QEMU should not send a file descriptor in a request to remove a memory region. Change it accordingly. For libvhost-user, this is a bug fix that makes it compatible with rust-vmm's implementation that doesn't send a file descriptor. Keep accepting, but ignoring a file descriptor for compatibility with older QEMU versions. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20220407133657.155281-4-kwolf@redhat.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-05-03util: rename qemu_*block() socket functionsMarc-André Lureau
The qemu_*block() functions are meant to be be used with sockets (the win32 implementation expects SOCKET) Over time, those functions where used with Win32 SOCKET or file-descriptors interchangeably. But for portability, they must only be used with socket-like file-descriptors. FDs can use g_unix_set_fd_nonblocking() instead. Rename the functions with "socket" in the name to prevent bad usages. This is effectively reverting commit f9e8cacc5557e43 ("oslib-posix: rename socket_set_nonblock() to qemu_set_nonblock()"). Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-04-06Replace qemu_real_host_page variables with inlined functionsMarc-André Lureau
Replace the global variables with inlined helper functions. getpagesize() is very likely annotated with a "const" function attribute (at least with glibc), and thus optimization should apply even better. This avoids the need for a constructor initialization too. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20220323155743.1585078-12-marcandre.lureau@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-04vhost-user: fix VirtQ notifier cleanupXueming Li
When vhost-user device cleanup, remove notifier MR and munmaps notifier address in the event-handling thread, VM CPU thread writing the notifier in concurrent fails with an error of accessing invalid address. It happens because MR is still being referenced and accessed in another thread while the underlying notifier mmap address is being freed and becomes invalid. This patch calls RCU and munmap notifiers in the callback after the memory flatview update finish. Fixes: 44866521bd6e ("vhost-user: support registering external host notifiers") Cc: qemu-stable@nongnu.org Signed-off-by: Xueming Li <xuemingl@nvidia.com> Message-Id: <20220207071929.527149-3-xuemingl@nvidia.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-04vhost-user: remove VirtQ notifier restoreXueming Li
Notifier set when vhost-user backend asks qemu to mmap an FD and offset. When vhost-user backend restart or getting killed, VQ notifier FD and mmap addresses become invalid. After backend restart, MR contains the invalid address will be restored and fail on notifier access. On the other hand, qemu should munmap the notifier, release underlying hardware resources to enable backend restart and allocate hardware notifier resources correctly. Qemu shouldn't reference and use resources of disconnected backend. This patch removes VQ notifier restore, uses the default vhost-user notifier to avoid invalid address access. After backend restart, the backend should ask qemu to install a hardware notifier if needed. Fixes: 44866521bd6e ("vhost-user: support registering external host notifiers") Cc: qemu-stable@nongnu.org Signed-off-by: Xueming Li <xuemingl@nvidia.com> Message-Id: <20220207071929.527149-2-xuemingl@nvidia.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-07vhost-user: stick to -errno error return conventionRoman Kagan
VhostOps methods in user_ops are not very consistent in their error returns: some return negated errno while others just -1. Make sure all of them consistently return negated errno. This also helps error propagation from the functions being called inside. Besides, this synchronizes the error return convention with the other two vhost backends, kernel and vdpa, and will therefore allow for consistent error propagation in the generic vhost code (in a followup patch). Signed-off-by: Roman Kagan <rvkagan@yandex-team.ru> Message-Id: <20211111153354.18807-9-rvkagan@yandex-team.ru> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-10-20vhost-user: fix duplicated notifier MR initXueming Li
In case of device resume after suspend, VQ notifier MR still valid. Duplicated registrations explode memory block list and slow down device resume. Fixes: 44866521bd6e ("vhost-user: support registering external host notifiers") Cc: tiwei.bie@intel.com Cc: qemu-stable@nongnu.org Cc: Yuwei Zhang <zhangyuwei.9149@bytedance.com> Signed-off-by: Xueming Li <xuemingl@nvidia.com> Message-Id: <20211008080215.590292-1-xuemingl@nvidia.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-04hw/virtio: Add flatview update in vhost_user_cleanup()Yuwei Zhang
Qemu will crash on vhost backend unexpected exit and re-connect │ in some case due to access released memory. Signed-off-by: Yuwei Zhang <zhangyuwei.9149@bytedance.com> Message-Id: <20210830123433.45727-1-zhangyuwei.9149@bytedance.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-04vhost-user: add missing space in error messageAlyssa Ross
This would previously give error messages like > Received unexpected msg type.Expected 0 received 1 Signed-off-by: Alyssa Ross <hi@alyssa.is> Message-Id: <20210806143926.315725-1-hi@alyssa.is> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-04vhost: make SET_VRING_ADDR, SET_FEATURES send repliesDenis Plotnikov
On vhost-user-blk migration, qemu normally sends a number of commands to enable logging if VHOST_USER_PROTOCOL_F_LOG_SHMFD is negotiated. Qemu sends VHOST_USER_SET_FEATURES to enable buffers logging and VHOST_USER_SET_VRING_ADDR per each started ring to enable "used ring" data logging. The issue is that qemu doesn't wait for reply from the vhost daemon for these commands which may result in races between qemu expectation of logging starting and actual login starting in vhost daemon. The race can appear as follows: on migration setup, qemu enables dirty page logging by sending VHOST_USER_SET_FEATURES. The command doesn't arrive to a vhost-user-blk daemon immediately and the daemon needs some time to turn the logging on internally. If qemu doesn't wait for reply, after sending the command, qemu may start migrateing memory pages to a destination. At this time, the logging may not be actually turned on in the daemon but some guest pages, which the daemon is about to write to, may have already been transferred without logging to the destination. Since the logging wasn't turned on, those pages won't be transferred again as dirty. So we may end up with corrupted data on the destination. The same scenario is applicable for "used ring" data logging, which is turned on with VHOST_USER_SET_VRING_ADDR command. To resolve this issue, this patch makes qemu wait for the command result explicitly if VHOST_USER_PROTOCOL_F_REPLY_ACK is negotiated and logging enabled. Signed-off-by: Denis Plotnikov <den-plotnikov@yandex-team.ru> Message-Id: <20210809104824.78830-1-den-plotnikov@yandex-team.ru> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-09-04hw/virtio: Fix leak of host-notifier memory-regionYajun Wu
If call virtio_queue_set_host_notifier_mr fails, should free host-notifier memory-region. Fixes: 44866521bd ("vhost-user: support registering external host notifiers") Signed-off-by: Yajun Wu <yajunw@nvidia.com> Message-Id: <1629077555-19907-1-git-send-email-yajunw@nvidia.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-08-26vhost: Clean up how VhostOpts method vhost_backend_init() failsMarkus Armbruster
vhost_user_backend_init() can fail without setting an error. Unclean. Its caller vhost_dev_init() compensates by substituting a generic error then. Goes back to commit 28770ff935 "vhost: Distinguish errors in vhost_backend_init()". Clean up by moving the generic error from vhost_dev_init() to all the failure paths that neglect to set an error. Cc: Kevin Wolf <kwolf@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20210720125408.387910-14-armbru@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2021-08-26vhost: Clean up how VhostOpts method vhost_get_config() failsMarkus Armbruster
vhost_user_get_config() can fail without setting an error. Unclean. Its caller vhost_dev_get_config() compensates by substituting a generic error then. Goes back to commit 50de51387f "vhost: Distinguish errors in vhost_dev_get_config()". Clean up by moving the generic error from vhost_dev_get_config() to all the failure paths that neglect to set an error. Cc: Kevin Wolf <kwolf@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20210720125408.387910-13-armbru@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> [Sign of error_setg_errno()'s second argument fixed in both calls]
2021-08-05chardev: mark explicitly first argument as poisonedMarc-André Lureau
Since commit 9894dc0cdcc397ee5b26370bc53da6d360a363c2 "char: convert from GIOChannel to QIOChannel", the first argument to the watch callback can actually be a QIOChannel, which is not a GIOChannel (but a QEMU Object). Even though we never used that pointer, change the callback type to warn the users. Possibly a better fix later, we may want to store the callback and call it from intermediary functions. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2021-07-09vhost-user: Fix backends without multiqueue supportKevin Wolf
dev->max_queues was never initialised for backends that don't support VHOST_USER_PROTOCOL_F_MQ, so it would use 0 as the maximum number of queues to check against and consequently fail for any such backend. Set it to 1 if the backend doesn't have multiqueue support. Fixes: c90bd505a3e8210c23d69fecab9ee6f56ec4a161 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20210705171429.29286-1-kwolf@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-06-30vhost: Distinguish errors in vhost_dev_get_config()Kevin Wolf
Instead of just returning 0/-1 and letting the caller make up a meaningless error message, add an Error parameter to allow reporting the real error and switch to 0/-errno so that different kind of errors can be distinguished in the caller. config_len in vhost_user_get_config() is defined by the device, so if it's larger than VHOST_USER_MAX_CONFIG_SIZE, this is a programming error. Turn the corresponding check into an assertion. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20210609154658.350308-6-kwolf@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-06-30vhost: Return 0/-errno in vhost_dev_init()Kevin Wolf
Instead of just returning 0/-1 and letting the caller make up a meaningless error message, switch to 0/-errno so that different kinds of errors can be distinguished in the caller. This involves changing a few more callbacks in VhostOps to return 0/-errno: .vhost_set_owner(), .vhost_get_features() and .vhost_virtqueue_set_busyloop_timeout(). The implementations of these functions are trivial as they generally just send a message to the backend. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20210609154658.350308-4-kwolf@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-06-30vhost: Distinguish errors in vhost_backend_init()Kevin Wolf
Instead of just returning 0/-1 and letting the caller make up a meaningless error message, add an Error parameter to allow reporting the real error and switch to 0/-errno so that different kind of errors can be distinguished in the caller. Specifically, in vhost-user, EPROTO is used for all errors that relate to the connection itself, whereas other error codes are used for errors relating to the content of the connection. This will allow us later to automatically reconnect when the connection goes away, without ending up in an endless loop if it's a permanent error in the configuration. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20210609154658.350308-3-kwolf@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-05-18vhost-user-blk: Check that num-queues is supported by backendKevin Wolf
Creating a device with a number of queues that isn't supported by the backend is pointless, the device won't work properly and the error messages are rather confusing. Just fail to create the device if num-queues is higher than what the backend supports. Since the relationship between num-queues and the number of virtqueues depends on the specific device, this is an additional value that needs to be initialised by the device. For convenience, allow leaving it 0 if the check should be skipped. This makes sense for vhost-user-net where separate vhost devices are used for the queues and custom initialisation code is needed to perform the check. Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1935031 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Message-Id: <20210429171316.162022-7-kwolf@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-03-22vhost-user: Monitor slave channel in vhost_user_read()Greg Kurz
Now that everything is in place, have the nested event loop to monitor the slave channel. The source in the main event loop is destroyed and recreated to ensure any pending even for the slave channel that was previously detected is purged. This guarantees that the main loop wont invoke slave_read() based on an event that was already handled by the nested loop. Signed-off-by: Greg Kurz <groug@kaod.org> Message-Id: <20210312092212.782255-7-groug@kaod.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2021-03-22vhost-user: Introduce nested event loop in vhost_user_read()Greg Kurz
A deadlock condition potentially exists if a vhost-user process needs to request something to QEMU on the slave channel while processing a vhost-user message. This doesn't seem to affect any vhost-user implementation so far, but this is currently biting the upcoming enablement of DAX with virtio-fs. The issue is being observed when the guest does an emergency reboot while a mapping still exits in the DAX window, which is very easy to get with a busy enough workload (e.g. as simulated by blogbench [1]) : - QEMU sends VHOST_USER_GET_VRING_BASE to virtiofsd. - In order to complete the request, virtiofsd then asks QEMU to remove the mapping on the slave channel. All these dialogs are synchronous, hence the deadlock. As pointed out by Stefan Hajnoczi: When QEMU's vhost-user master implementation sends a vhost-user protocol message, vhost_user_read() does a "blocking" read during which slave_fd is not monitored by QEMU. The natural solution for this issue is an event loop. The main event loop cannot be nested though since we have no guarantees that its fd handlers are prepared for re-entrancy. Introduce a new event loop that only monitors the chardev I/O for now in vhost_user_read() and push the actual reading to a one-shot handler. A subsequent patch will teach the loop to monitor and process messages from the slave channel as well. [1] https://github.com/jedisct1/Blogbench Suggested-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Greg Kurz <groug@kaod.org> Message-Id: <20210312092212.782255-6-groug@kaod.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2021-03-22vhost-user: Convert slave channel to QIOChannelSocketGreg Kurz
The slave channel is implemented with socketpair() : QEMU creates the pair, passes one of the socket to virtiofsd and monitors the other one with the main event loop using qemu_set_fd_handler(). In order to fix a potential deadlock between QEMU and a vhost-user external process (e.g. virtiofsd with DAX), we want to be able to monitor and service the slave channel while handling vhost-user requests. Prepare ground for this by converting the slave channel to be a QIOChannelSocket. This will make monitoring of the slave channel as simple as calling qio_channel_add_watch_source(). Since the connection is already established between the two sockets, only incoming I/O (G_IO_IN) and disconnect (G_IO_HUP) need to be serviced. This also allows to get rid of the ancillary data parsing since QIOChannelSocket can do this for us. Note that the MSG_CTRUNC check is dropped on the way because QIOChannelSocket ignores this case. This isn't a problem since slave_read() provisions space for 8 file descriptors, but affected vhost-user slave protocol messages generally only convey one. If for some reason a buggy implementation passes more file descriptors, no need to break the connection, just like we don't break it if some other type of ancillary data is received : this isn't explicitely violating the protocol per-se so it seems better to ignore it. The current code errors out on short reads and writes. Use the qio_channel_*_all() variants to address this on the way. Signed-off-by: Greg Kurz <groug@kaod.org> Message-Id: <20210312092212.782255-5-groug@kaod.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2021-03-22vhost-user: Factor out duplicated slave_fd teardown codeGreg Kurz
Signed-off-by: Greg Kurz <groug@kaod.org> Message-Id: <20210312092212.782255-4-groug@kaod.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2021-03-22vhost-user: Fix double-close on slave_read() error pathGreg Kurz
Some message types, e.g. VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG, can convey file descriptors. These must be closed before returning from slave_read() to avoid being leaked. This can currently be done in two different places: [1] just after the request has been processed [2] on the error path, under the goto label err: These path are supposed to be mutually exclusive but they are not actually. If the VHOST_USER_NEED_REPLY_MASK flag was passed and the sending of the reply fails, both [1] and [2] are performed with the same descriptor values. This can potentially cause subtle bugs if one of the descriptor was recycled by some other thread in the meantime. This code duplication complicates rollback for no real good benefit. Do the closing in a unique place, under a new fdcleanup: goto label at the end of the function. Signed-off-by: Greg Kurz <groug@kaod.org> Message-Id: <20210312092212.782255-3-groug@kaod.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2021-03-22vhost-user: Drop misleading EAGAIN checks in slave_read()Greg Kurz
slave_read() checks EAGAIN when reading or writing to the socket fails. This gives the impression that the slave channel is in non-blocking mode, which is certainly not the case with the current code base. And the rest of the code isn't actually ready to cope with non-blocking I/O. Just drop the checks everywhere in this function for the sake of clarity. Signed-off-by: Greg Kurz <groug@kaod.org> Message-Id: <20210312092212.782255-2-groug@kaod.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-11-12vhost-user: fix VHOST_USER_ADD/REM_MEM_REG truncationStefan Hajnoczi
QEMU currently truncates the mmap_offset field when sending VHOST_USER_ADD_MEM_REG and VHOST_USER_REM_MEM_REG messages. The struct layout looks like this: typedef struct VhostUserMemoryRegion { uint64_t guest_phys_addr; uint64_t memory_size; uint64_t userspace_addr; uint64_t mmap_offset; } VhostUserMemoryRegion; typedef struct VhostUserMemRegMsg { uint32_t padding; /* WARNING: there is a 32-bit hole here! */ VhostUserMemoryRegion region; } VhostUserMemRegMsg; The payload size is calculated as follows when sending the message in hw/virtio/vhost-user.c: msg->hdr.size = sizeof(msg->payload.mem_reg.padding) + sizeof(VhostUserMemoryRegion); This calculation produces an incorrect result of only 36 bytes. sizeof(VhostUserMemRegMsg) is actually 40 bytes. The consequence of this is that the final field, mmap_offset, is truncated. This breaks x86_64 TCG guests on s390 hosts. Other guest/host combinations may get lucky if either of the following holds: 1. The guest memory layout does not need mmap_offset != 0. 2. The host is little-endian and mmap_offset <= 0xffffffff so the truncation has no effect. Fix this by extending the existing 32-bit padding field to 64-bit. Now the padding reflects the actual compiler padding. This can be verified using pahole(1). Also document the layout properly in the vhost-user specification. The vhost-user spec did not document the exact layout. It would be impossible to implement the spec without looking at the QEMU source code. Existing vhost-user frontends and device backends continue to work after this fix has been applied. The only change in the wire protocol is that QEMU now sets hdr.size to 40 instead of 36. If a vhost-user implementation has a hardcoded size check for 36 bytes, then it will fail with new QEMUs. Both QEMU and DPDK/SPDK don't check the exact payload size, so they continue to work. Fixes: f1aeb14b0809e313c74244d838645ed25e85ea63 ("Transmit vhost-user memory regions individually") Cc: Raphael Norwitz <raphael.norwitz@nutanix.com> Cc: Cornelia Huck <cohuck@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20201109174355.1069147-1-stefanha@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Fixes: f1aeb14b0809 ("Transmit vhost-user memory regions individually") Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
2020-09-01hw/virtio/vhost-user:Remove dead assignment in scrub_shadow_regions()Chen Qun
Clang static code analyzer show warning: hw/virtio/vhost-user.c:606:9: warning: Value stored to 'mr' is never read mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Reported-by: Euler Robot <euler.robot@huawei.com> Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Message-Id: <20200827110311.164316-6-kuhn.chenqun@huawei.com> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-07-27Fix vhost-user buffer over-read on ram hot-unplugRaphael Norwitz
The VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS vhost-user protocol feature introduced a shadow-table, used by the backend to dynamically determine how a vdev's memory regions have changed since the last vhost_user_set_mem_table() call. On hot-remove, a memmove() operation is used to overwrite the removed shadow region descriptor(s). The size parameter of this memmove was off by 1 such that if a VM with a backend supporting the VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS filled it's shadow-table (by performing the maximum number of supported hot-add operatons) and attempted to remove the last region, Qemu would read an out of bounds value and potentially crash. This change fixes the memmove() bounds such that this erroneous read can never happen. Signed-off-by: Peter Turschmid <peter.turschm@nutanix.com> Signed-off-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Message-Id: <1594799958-31356-1-git-send-email-raphael.norwitz@nutanix.com> Fixes: f1aeb14b0809 ("Transmit vhost-user memory regions individually") Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Cc: qemu-stable@nongnu.org Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-11 19:30:40 +0000