build: Release v51.2

Signed-off-by: Bo Chen <bchen@crusoe.ai>

Cargo.lock

@@ -427,7 +427,7 @@ checksum = "3a822ea5bc7590f9d40f1ba12c0dc3c2760f3482c6984db1573ad11031420831"
 
 [[package]]
 name = "cloud-hypervisor"
-version = "51.0.0"
+version = "51.2.0"
 dependencies = [
  "anyhow",
  "api_client",

arch/src/x86_64/mod.rs

@@ -641,17 +641,16 @@ pub fn generate_common_cpuid(
 
     // Update some existing CPUID
     for entry in cpuid.as_mut_slice().iter_mut() {
+        #[allow(unused_unsafe)]
         match entry.function {
             // Clear AMX related bits if the AMX feature is not enabled
-            0x7 => {
+            0x7 if !config.amx => {
-                if !config.amx {
+                if entry.index == 0 {
-                    if entry.index == 0 {
+                    entry.edx &= !((1 << AMX_BF16) | (1 << AMX_TILE) | (1 << AMX_INT8));
-                        entry.edx &= !((1 << AMX_BF16) | (1 << AMX_TILE) | (1 << AMX_INT8));
+                }
-                    }
+                if entry.index == 1 {
-                    if entry.index == 1 {
+                    entry.eax &= !(1 << AMX_FP16);
-                        entry.eax &= !(1 << AMX_FP16);
+                    entry.edx &= !(1 << AMX_COMPLEX);
-                        entry.edx &= !(1 << AMX_COMPLEX);
-                    }
                 }
             }
             0xd =>
@@ -673,55 +672,46 @@ pub fn generate_common_cpuid(
                     }
                 }
             }
-            0x1d => {
+            // Tile Information (purely AMX related).
-                // Tile Information (purely AMX related).
+            0x1d if !config.amx => {
-                if !config.amx {
+                entry.eax = 0;
-                    entry.eax = 0;
+                entry.ebx = 0;
-                    entry.ebx = 0;
+                entry.ecx = 0;
-                    entry.ecx = 0;
+                entry.edx = 0;
-                    entry.edx = 0;
-                }
             }
-            0x1e => {
+            // TMUL information (purely AMX related)
-                // TMUL information (purely AMX related)
+            0x1e if !config.amx => {
-                if !config.amx {
+                entry.eax = 0;
-                    entry.eax = 0;
+                entry.ebx = 0;
-                    entry.ebx = 0;
+                entry.ecx = 0;
-                    entry.ecx = 0;
+                entry.edx = 0;
-                    entry.edx = 0;
-                }
             }
 
             // Copy host L1 cache details if not populated by KVM
-            0x8000_0005 => {
+            0x8000_0005
-                if entry.eax == 0 && entry.ebx == 0 && entry.ecx == 0 && entry.edx == 0 {
+                if entry.eax == 0 && entry.ebx == 0 && entry.ecx == 0 && entry.edx == 0
-                    #[allow(unused_unsafe)]
                     // SAFETY: cpuid called with valid leaves
-                    if unsafe { std::arch::x86_64::__cpuid(0x8000_0000).eax } >= 0x8000_0005 {
+                    && unsafe { std::arch::x86_64::__cpuid(0x8000_0000).eax } >= 0x8000_0005 =>
-                        // SAFETY: cpuid called with valid leaves
+            {
-                        let leaf = unsafe { std::arch::x86_64::__cpuid(0x8000_0005) };
+                // SAFETY: cpuid called with valid leaves
-                        entry.eax = leaf.eax;
+                let leaf = unsafe { std::arch::x86_64::__cpuid(0x8000_0005) };
-                        entry.ebx = leaf.ebx;
+                entry.eax = leaf.eax;
-                        entry.ecx = leaf.ecx;
+                entry.ebx = leaf.ebx;
-                        entry.edx = leaf.edx;
+                entry.ecx = leaf.ecx;
-                    }
+                entry.edx = leaf.edx;
-                }
             }
             // Copy host L2 cache details if not populated by KVM
-            0x8000_0006 => {
+            0x8000_0006
-                if entry.eax == 0 && entry.ebx == 0 && entry.ecx == 0 && entry.edx == 0 {
+                if entry.eax == 0 && entry.ebx == 0 && entry.ecx == 0 && entry.edx == 0
-                    #[allow(unused_unsafe)]
                     // SAFETY: cpuid called with valid leaves
-                    if unsafe { std::arch::x86_64::__cpuid(0x8000_0000).eax } >= 0x8000_0006 {
+                    && unsafe { std::arch::x86_64::__cpuid(0x8000_0000).eax } >= 0x8000_0006 =>
-                        #[allow(unused_unsafe)]
+            {
-                        // SAFETY: cpuid called with valid leaves
+                // SAFETY: cpuid called with valid leaves
-                        let leaf = unsafe { std::arch::x86_64::__cpuid(0x8000_0006) };
+                let leaf = unsafe { std::arch::x86_64::__cpuid(0x8000_0006) };
-                        entry.eax = leaf.eax;
+                entry.eax = leaf.eax;
-                        entry.ebx = leaf.ebx;
+                entry.ebx = leaf.ebx;
-                        entry.ecx = leaf.ecx;
+                entry.ecx = leaf.ecx;
-                        entry.edx = leaf.edx;
+                entry.edx = leaf.edx;
-                    }
-                }
             }
             // Set CPU physical bits
             0x8000_0008 => {

block/src/aligned_operation.rs

@@ -0,0 +1,90 @@
+// Copyright (c) 2026 Meta Platforms, Inc. and affiliates.
+//
+// SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
+
+use std::alloc::{Layout, alloc_zeroed, dealloc};
+use std::io;
+
+use vm_memory::GuestAddress;
+
+/// Owns an aligned bounce buffer used when a guest descriptor's host VA
+/// does not meet the disk backend's alignment requirement.
+#[derive(Debug)]
+pub struct AlignedOperation {
+    data_addr: GuestAddress,
+    aligned_ptr: *mut u8,
+    size: usize,
+    layout: Layout,
+}
+
+impl AlignedOperation {
+    /// Allocate a zero-initialized buffer of `size` bytes aligned to
+    /// `alignment`. Returns `InvalidInput` if `size` is zero;
+    /// `alignment` must be a power of two and not exceed `isize::MAX`
+    /// after rounding up.
+    pub fn new(data_addr: GuestAddress, size: usize, alignment: usize) -> io::Result<Self> {
+        if size == 0 {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidInput,
+                "AlignedOperation requires a non-zero size",
+            ));
+        }
+        let layout = Layout::from_size_align(size, alignment)
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidInput, e))?;
+        // SAFETY: size is non-zero (checked above) and Layout::from_size_align
+        // rejects alignments that are not a power of two or that overflow.
+        let aligned_ptr = unsafe { alloc_zeroed(layout) };
+        if aligned_ptr.is_null() {
+            return Err(io::Error::last_os_error());
+        }
+        Ok(Self {
+            data_addr,
+            aligned_ptr,
+            size,
+            layout,
+        })
+    }
+
+    /// Gets the raw pointer to the aligned buffer.
+    pub fn as_mut_ptr(&mut self) -> *mut u8 {
+        self.aligned_ptr
+    }
+
+    /// Returns the aligned buffer as a slice.
+    pub fn as_bytes(&self) -> &[u8] {
+        // SAFETY: `new` allocates `size` bytes via alloc_zeroed (so they
+        // are initialized) and AlignedOperation owns the buffer
+        // exclusively.
+        unsafe { std::slice::from_raw_parts(self.aligned_ptr, self.size) }
+    }
+
+    /// Returns the aligned buffer as a mutable slice.
+    pub fn as_bytes_mut(&mut self) -> &mut [u8] {
+        // SAFETY: same invariant as as_bytes; &mut self rules out other
+        // simultaneous borrows.
+        unsafe { std::slice::from_raw_parts_mut(self.aligned_ptr, self.size) }
+    }
+
+    /// Returns the guest address for this op.
+    pub fn data_addr(&self) -> GuestAddress {
+        self.data_addr
+    }
+}
+
+impl Drop for AlignedOperation {
+    fn drop(&mut self) {
+        // SAFETY: `new` is the only constructor, and it stores a pointer
+        // returned by `alloc_zeroed` paired with the exact `layout` used
+        // for that allocation. Ownership has not escaped (the type is
+        // neither `Clone` nor `Copy`).
+        unsafe {
+            dealloc(self.aligned_ptr, self.layout);
+        }
+    }
+}
+
+// SAFETY: AlignedOperation owns its heap allocation exclusively (no Clone/
+// Copy, no shared aliases) and the allocation's lifetime is tied to the
+// value's. Moving an AlignedOperation between threads transfers that
+// ownership; the same rationale Box<T> uses for its Send impl.
+unsafe impl Send for AlignedOperation {}

block/src/lib.rs

@@ -8,6 +8,7 @@
 //
 // SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
 
+mod aligned_operation;
 pub mod async_io;
 pub mod fcntl;
 pub mod fixed_vhd;
@@ -28,7 +29,7 @@ pub mod vhd;
 pub mod vhdx;
 pub mod vhdx_sync;
 
-use std::alloc::{Layout, alloc_zeroed, dealloc};
+use std::alloc::{Layout, alloc_zeroed};
 use std::collections::VecDeque;
 use std::fmt::{self, Debug};
 use std::fs::File;
@@ -40,6 +41,7 @@ use std::str::FromStr;
 use std::time::Instant;
 use std::{cmp, result};
 
+pub use aligned_operation::AlignedOperation;
 #[cfg(feature = "io_uring")]
 use io_uring::{IoUring, Probe, opcode};
 use libc::{S_IFBLK, S_IFMT, ioctl};
@@ -232,14 +234,6 @@ fn sector<B: Bitmap + 'static>(
 
 const DEFAULT_DESCRIPTOR_VEC_SIZE: usize = 32;
 
-#[derive(Debug)]
-pub struct AlignedOperation {
-    origin_ptr: u64,
-    aligned_ptr: u64,
-    size: usize,
-    layout: Layout,
-}
-
 pub struct BatchRequest {
     pub offset: libc::off_t,
     pub iovecs: SmallVec<[libc::iovec; DEFAULT_DESCRIPTOR_VEC_SIZE]>,
@@ -473,31 +467,19 @@ impl Request {
             let iov_base = if (origin_ptr.as_ptr() as u64).is_multiple_of(SECTOR_SIZE) {
                 origin_ptr.as_ptr() as *mut libc::c_void
             } else {
-                let layout = Layout::from_size_align(data_len, SECTOR_SIZE as usize).unwrap();
+                let mut aligned_op =
-                // SAFETY: layout has non-zero size
+                    AlignedOperation::new(data_addr, data_len, SECTOR_SIZE as usize)
-                let aligned_ptr = unsafe { alloc_zeroed(layout) };
+                        .map_err(ExecuteError::TemporaryBufferAllocation)?;
-                if aligned_ptr.is_null() {
-                    return Err(ExecuteError::TemporaryBufferAllocation(
-                        io::Error::last_os_error(),
-                    ));
-                }
 
                 // We need to perform the copy beforehand in case we're writing
                 // data out.
                 if request_type == RequestType::Out {
-                    // SAFETY: destination buffer has been allocated with
+                    mem.read_slice(aligned_op.as_bytes_mut(), data_addr)
-                    // the proper size.
+                        .map_err(ExecuteError::Read)?;
-                    unsafe { std::ptr::copy(origin_ptr.as_ptr(), aligned_ptr, data_len) };
                 }
 
-                // Store both origin and aligned pointers for complete_async()
+                let aligned_ptr = aligned_op.as_mut_ptr();
-                // to process them.
+                self.aligned_operations.push(aligned_op);
-                self.aligned_operations.push(AlignedOperation {
-                    origin_ptr: origin_ptr.as_ptr() as u64,
-                    aligned_ptr: aligned_ptr as u64,
-                    size: data_len,
-                    layout,
-                });
 
                 aligned_ptr as *mut libc::c_void
             };
@@ -639,31 +621,17 @@ impl Request {
         Ok(ret)
     }
 
-    pub fn complete_async(&mut self) -> result::Result<(), Error> {
+    pub fn complete_async<B: Bitmap + 'static>(
-        for aligned_operation in self.aligned_operations.drain(..) {
+        &mut self,
+        mem: &vm_memory::GuestMemoryMmap<B>,
+    ) -> result::Result<(), Error> {
+        for aligned_op in self.aligned_operations.drain(..) {
             // We need to perform the copy after the data has been read inside
             // the aligned buffer in case we're reading data in.
             if self.request_type == RequestType::In {
-                // SAFETY: origin buffer has been allocated with the
+                mem.write_slice(aligned_op.as_bytes(), aligned_op.data_addr())
-                // proper size.
+                    .map_err(Error::GuestMemory)?;
-                unsafe {
-                    std::ptr::copy(
-                        aligned_operation.aligned_ptr as *const u8,
-                        aligned_operation.origin_ptr as *mut u8,
-                        aligned_operation.size,
-                    );
-                };
             }
-
-            // Free the temporary aligned buffer.
-            // SAFETY: aligned_ptr was allocated by alloc_zeroed with the same
-            // layout
-            unsafe {
-                dealloc(
-                    aligned_operation.aligned_ptr as *mut u8,
-                    aligned_operation.layout,
-                );
-            };
         }
 
         Ok(())

block/src/raw_async.rs

@@ -197,6 +197,14 @@ impl AsyncIo for RawFileAsync {
         let (submitter, mut sq, _) = self.io_uring.split();
         let mut submitted = false;
 
+        // Refuse the whole batch if it can't fit in the SQ to avoid having to unroll a partially
+        // successful push.
+        if batch_request.len() > sq.capacity() - sq.len() {
+            return Err(AsyncIoError::SubmitBatchRequests(Error::other(
+                "io_uring submission queue is full",
+            )));
+        }
+
         for req in batch_request {
             match req.request_type {
                 RequestType::In => {

cloud-hypervisor/Cargo.toml

@@ -7,7 +7,7 @@ edition = "2024"
 homepage = "https://github.com/cloud-hypervisor/cloud-hypervisor"
 license = "Apache-2.0 AND BSD-3-Clause"
 name = "cloud-hypervisor"
-version = "51.0.0"
+version = "51.2.0"
 # Minimum buildable version:
 # Keep in sync with version in .github/workflows/build.yaml
 # Policy on MSRV (see #4318):

fuzz/fuzz_targets/balloon.rs

@@ -95,15 +95,16 @@ fuzz_target!(|bytes: &[u8]| -> Corpus {
     reporting_queue_evt.write(1).unwrap();
 
     balloon
-        .activate(
+        .activate(virtio_devices::ActivationContext {
-            guest_memory,
+            mem: guest_memory,
-            Arc::new(NoopVirtioInterrupt {}),
+            interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
-            vec![
+            queues: vec![
                 (0, inflate_q, inflate_evt),
                 (1, deflate_q, deflate_evt),
                 (2, reporting_q, reporting_evt),
             ],
-        )
+            device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+        })
         .ok();
 
     // Wait for the events to finish and balloon device worker thread to return

fuzz/fuzz_targets/block.rs

@@ -89,11 +89,12 @@ fuzz_target!(|bytes: &[u8]| -> Corpus {
     queue_evt.write(1).unwrap();
 
     block
-        .activate(
+        .activate(virtio_devices::ActivationContext {
-            guest_memory,
+            mem: guest_memory,
-            Arc::new(NoopVirtioInterrupt {}),
+            interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
-            vec![(0, q, evt)],
+            queues: vec![(0, q, evt)],
-        )
+            device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+        })
         .ok();
 
     // Wait for the events to finish and block device worker thread to return

fuzz/fuzz_targets/console.rs

@@ -128,11 +128,12 @@ fuzz_target!(|bytes: &[u8]| -> Corpus {
     pipe_tx.write_all(console_input_bytes).unwrap(); // To use fuzzed data;
 
     console
-        .activate(
+        .activate(virtio_devices::ActivationContext {
-            guest_memory,
+            mem: guest_memory,
-            Arc::new(NoopVirtioInterrupt {}),
+            interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
-            vec![(0, input_queue, input_evt), (1, output_queue, output_evt)],
+            queues: vec![(0, input_queue, input_evt), (1, output_queue, output_evt)],
-        )
+            device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+        })
         .unwrap();
 
     // Wait for the events to finish and console device worker thread to return

fuzz/fuzz_targets/iommu.rs

@@ -107,14 +107,15 @@ fuzz_target!(|bytes: &[u8]| -> Corpus {
     request_queue_evt.write(1).unwrap();
 
     iommu
-        .activate(
+        .activate(virtio_devices::ActivationContext {
-            guest_memory,
+            mem: guest_memory,
-            Arc::new(NoopVirtioInterrupt {}),
+            interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
-            vec![
+            queues: vec![
                 (0, request_queue, request_evt),
                 (0, _event_queue, _event_evt),
             ],
-        )
+            device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+        })
         .ok();
 
     // Wait for the events to finish and vIOMMU device worker thread to return

fuzz/fuzz_targets/mem.rs

@@ -105,11 +105,12 @@ fuzz_target!(|bytes: &[u8]| -> Corpus {
     queue_evt.write(1).unwrap();
 
     virtio_mem
-        .activate(
+        .activate(virtio_devices::ActivationContext {
-            guest_memory,
+            mem: guest_memory,
-            Arc::new(NoopVirtioInterrupt {}),
+            interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
-            vec![(0, q, evt)],
+            queues: vec![(0, q, evt)],
-        )
+            device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+        })
         .ok();
 
     // Wait for the events to finish and virtio-mem device worker thread to return

fuzz/fuzz_targets/net.rs

@@ -143,11 +143,12 @@ fuzz_target!(|bytes: &[u8]| -> Corpus {
     input_queue_evt.write(1).unwrap();
     output_queue_evt.write(1).unwrap();
 
-    net.activate(
+    net.activate(virtio_devices::ActivationContext {
-        guest_memory,
+        mem: guest_memory,
-        Arc::new(NoopVirtioInterrupt {}),
+        interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
-        vec![(0, input_queue, input_evt), (1, output_queue, output_evt)],
+        queues: vec![(0, input_queue, input_evt), (1, output_queue, output_evt)],
-    )
+        device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+    })
     .unwrap();
 
     // Wait for the events to finish and net device worker thread to return

fuzz/fuzz_targets/pmem.rs

@@ -61,11 +61,12 @@ fuzz_target!(|bytes: &[u8]| -> Corpus {
     // Kick the 'queue' event before activate the pmem device
     queue_evt.write(1).unwrap();
 
-    pmem.activate(
+    pmem.activate(virtio_devices::ActivationContext {
-        guest_memory,
+        mem: guest_memory,
-        Arc::new(NoopVirtioInterrupt {}),
+        interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
-        vec![(0, q, evt)],
+        queues: vec![(0, q, evt)],
-    )
+        device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+    })
     .ok();
 
     // Wait for the events to finish and pmem device worker thread to return

fuzz/fuzz_targets/rng.rs

@@ -99,11 +99,12 @@ fuzz_target!(|bytes: &[u8]| -> Corpus {
     // Kick the 'queue' event before activate the rng device
     queue_evt.write(1).unwrap();
 
-    rng.activate(
+    rng.activate(virtio_devices::ActivationContext {
-        guest_memory,
+        mem: guest_memory,
-        Arc::new(NoopVirtioInterrupt {}),
+        interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
-        vec![(0, q, evt)],
+        queues: vec![(0, q, evt)],
-    )
+        device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+    })
     .ok();
 
     // Wait for the events to finish and rng device worker thread to return

fuzz/fuzz_targets/vsock.rs

@@ -108,11 +108,12 @@ fuzz_target!(|bytes: &[u8]| -> Corpus {
     .unwrap();
 
     vsock
-        .activate(
+        .activate(virtio_devices::ActivationContext {
-            guest_memory,
+            mem: guest_memory,
-            Arc::new(NoopVirtioInterrupt {}),
+            interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
-            vec![(0, q, evt)],
+            queues: vec![(0, q, evt)],
-        )
+            device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+        })
         .ok();
 
     // Wait for the events to finish and vsock device worker thread to return

fuzz/fuzz_targets/watchdog.rs

@@ -64,11 +64,12 @@ fuzz_target!(|bytes: &[u8]| -> Corpus {
     queue_evt.write(1).unwrap();
 
     watchdog
-        .activate(
+        .activate(virtio_devices::ActivationContext {
-            guest_memory,
+            mem: guest_memory,
-            Arc::new(NoopVirtioInterrupt {}),
+            interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
-            vec![(0, q, evt)],
+            queues: vec![(0, q, evt)],
-        )
+            device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+        })
         .ok();
 
     // Wait for the events to finish and watchdog device worker thread to return

hypervisor/src/kvm/mod.rs

@@ -90,11 +90,11 @@ pub use kvm_bindings::kvm_vcpu_events as VcpuEvents;
 #[cfg(target_arch = "x86_64")]
 use kvm_bindings::nested::KvmNestedStateBuffer;
 pub use kvm_bindings::{
-    KVM_GUESTDBG_ENABLE, KVM_GUESTDBG_SINGLESTEP, KVM_IRQ_ROUTING_IRQCHIP, KVM_IRQ_ROUTING_MSI,
+    self, KVM_GUESTDBG_ENABLE, KVM_GUESTDBG_SINGLESTEP, KVM_IRQ_ROUTING_IRQCHIP,
-    KVM_MEM_LOG_DIRTY_PAGES, KVM_MEM_READONLY, KVM_MSI_VALID_DEVID, kvm_clock_data,
+    KVM_IRQ_ROUTING_MSI, KVM_MEM_LOG_DIRTY_PAGES, KVM_MEM_READONLY, KVM_MSI_VALID_DEVID,
-    kvm_create_device, kvm_create_device as CreateDevice, kvm_device_attr as DeviceAttr,
+    kvm_clock_data, kvm_create_device, kvm_create_device as CreateDevice,
-    kvm_device_type_KVM_DEV_TYPE_VFIO, kvm_guest_debug, kvm_irq_routing, kvm_irq_routing_entry,
+    kvm_device_attr as DeviceAttr, kvm_device_type_KVM_DEV_TYPE_VFIO, kvm_guest_debug,
-    kvm_mp_state, kvm_run, kvm_userspace_memory_region,
+    kvm_irq_routing, kvm_irq_routing_entry, kvm_mp_state, kvm_run, kvm_userspace_memory_region,
 };
 #[cfg(target_arch = "aarch64")]
 use kvm_bindings::{
@@ -109,14 +109,13 @@ use kvm_bindings::{KVM_REG_RISCV_CORE, kvm_riscv_core};
 use kvm_bindings::{KVM_X86_DEFAULT_VM, KVM_X86_SW_PROTECTED_VM, KVMIO, kvm_run__bindgen_ty_1};
 #[cfg(target_arch = "x86_64")]
 use kvm_bindings::{Xsave as xsave2, kvm_xsave2};
-pub use kvm_ioctls::{Cap, Kvm, VcpuExit};
+pub use kvm_ioctls::{self, Cap, Kvm, VcpuExit};
 use thiserror::Error;
 use vfio_ioctls::VfioDeviceFd;
 #[cfg(target_arch = "x86_64")]
 use vmm_sys_util::{fam::FamStruct, ioctl_io_nr};
 #[cfg(feature = "tdx")]
 use vmm_sys_util::{ioctl::ioctl_with_val, ioctl_iowr_nr};
-pub use {kvm_bindings, kvm_ioctls};
 
 #[cfg(any(target_arch = "aarch64", target_arch = "riscv64"))]
 use crate::RegList;

net_util/src/queue_pair.rs

@@ -51,7 +51,13 @@ impl TxVirtio {
         let mut retry_write = false;
         let mut rate_limit_reached = false;
 
-        while let Some(mut desc_chain) = queue.pop_descriptor_chain(mem) {
+        loop {
+            let mut iter = queue
+                .iter(mem)
+                .map_err(NetQueuePairError::QueueIteratorFailed)?;
+            let Some(mut desc_chain) = iter.next() else {
+                break;
+            };
             if rate_limit_reached {
                 queue.go_to_previous_position();
                 break;
@@ -180,7 +186,13 @@ impl RxVirtio {
         let mut exhausted_descs = true;
         let mut rate_limit_reached = false;
 
-        while let Some(mut desc_chain) = queue.pop_descriptor_chain(mem) {
+        loop {
+            let mut iter = queue
+                .iter(mem)
+                .map_err(NetQueuePairError::QueueIteratorFailed)?;
+            let Some(mut desc_chain) = iter.next() else {
+                break;
+            };
             if rate_limit_reached {
                 exhausted_descs = false;
                 queue.go_to_previous_position();

release-notes.md

@@ -1,3 +1,5 @@
+- [v51.2](#v512)
+- [v51.1](#v511)
 - [v51.0](#v510)
     - [Security Fixes](#security-fixes)
     - [Significant QCOW2 v3 Improvements](#significant-qcow2-v3-improvements)
@@ -418,6 +420,18 @@
     - [Unit testing](#unit-testing)
     - [Integration tests parallelization](#integration-tests-parallelization)
 
+# v51.2
+
+This is a point release containing security fixes to a use-after-free
+vulnerability in the `virtio-block` async I/O completion path
+(#8220). Details can be found in GHSA-f47p-p25q-83rh (CVE-2026-45782).
+
+# v51.1
+
+This is a bug fix release. The following issues have been addressed:
+
+* Fix image_type in OpenAPI definition (#7734)
+
 # v51.0
 
 This release has been tracked in [v51.0

virtio-devices/src/balloon.rs

@@ -590,12 +590,13 @@ impl VirtioDevice for Balloon {
         }
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        mut queues: Vec<(usize, Queue, EventFd)>,
+            mut queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.common.activate(&queues, interrupt_cb.clone())?;
         let (kill_evt, pause_evt) = self.common.dup_eventfds();
 

virtio-devices/src/block.rs

@@ -13,7 +13,7 @@ use std::num::Wrapping;
 use std::ops::Deref;
 use std::os::unix::io::AsRawFd;
 use std::path::PathBuf;
-use std::sync::atomic::{AtomicBool, AtomicU64, Ordering};
+use std::sync::atomic::{AtomicBool, AtomicU8, AtomicU64, Ordering};
 use std::sync::{Arc, Barrier};
 use std::{io, result};
 
@@ -161,6 +161,7 @@ struct BlockEpollHandler {
     host_cpus: Option<Vec<usize>>,
     acked_features: u64,
     disable_sector0_writes: bool,
+    device_status: Arc<AtomicU8>,
 }
 
 fn has_feature(features: u64, feature_flag: u64) -> bool {
@@ -168,6 +169,10 @@ fn has_feature(features: u64, feature_flag: u64) -> bool {
 }
 
 impl BlockEpollHandler {
+    fn needs_reset(&self) -> bool {
+        (self.device_status.load(Ordering::Acquire) & crate::DEVICE_NEEDS_RESET as u8) != 0
+    }
+
     fn check_request(
         features: u64,
         request: &Request,
@@ -192,12 +197,71 @@ impl BlockEpollHandler {
         Ok(())
     }
 
+    fn handle_queue_iterator_error(&mut self, err: &virtio_queue::Error) {
+        // The guest submitted a corrupted VirtQ request, and the error
+        // was logged during queue processing. We cannot just ignore the
+        // error, as the guest could continue spamming the VMM with bad
+        // requests, triggering excessive error logging. So we mark
+        // the device "NEEDS_RESET", effectively stopping all request
+        // processing (see self.needs_reset() usage) until the guest
+        // resets and reactivates the device.
+
+        warn!(
+            "Corrupted request detected (virtqueue error: {err:?}). \
+Setting device status to 'NEEDS_RESET' and stopping processing queues until reset."
+        );
+
+        self.set_needs_reset();
+    }
+
+    fn set_needs_reset(&mut self) {
+        self.device_status
+            .fetch_or(crate::DEVICE_NEEDS_RESET as u8, Ordering::SeqCst);
+
+        // Let the guest know that the device status has changed.
+        if let Err(e) = self.interrupt_cb.trigger(VirtioInterruptType::Config) {
+            error!("Failed to signal config interrupt: {e:?}");
+        }
+    }
+
+    // A spec-compliant driver never reuses a virtqueue head_index while the
+    // corresponding chain is still available (virtio 1.x §2.7.13.4).
+    // Double check the guest driver is behaving.
+    fn is_head_in_flight(
+        inflight: &VecDeque<(u16, Request)>,
+        batch: &[(u16, Request)],
+        head: u16,
+    ) -> bool {
+        batch.iter().any(|(h, _)| *h == head) || inflight.iter().any(|(h, _)| *h == head)
+    }
+
     fn process_queue_submit(&mut self) -> Result<()> {
+        if self.needs_reset() {
+            return Ok(());
+        }
         let queue = &mut self.queue;
         let mut batch_requests = Vec::new();
         let mut batch_inflight_requests = Vec::new();
 
-        while let Some(mut desc_chain) = queue.pop_descriptor_chain(self.mem.memory()) {
+        loop {
+            let mut desc_chain = match queue.iter(self.mem.memory()) {
+                Ok(mut iter) => match iter.next() {
+                    Some(c) => c,
+                    None => break,
+                },
+                Err(err) => {
+                    self.handle_queue_iterator_error(&err);
+                    return Ok(());
+                }
+            };
+
+            let head = desc_chain.head_index();
+            if Self::is_head_in_flight(&self.inflight_requests, &batch_inflight_requests, head) {
+                warn!("Guest reused virtio-blk head_index {head} while the chain was used");
+                self.set_needs_reset();
+                return Ok(());
+            }
+
             let mut request = Request::parse(&mut desc_chain, self.access_platform.as_deref())
                 .map_err(Error::RequestParsing)?;
 
@@ -282,8 +346,11 @@ impl BlockEpollHandler {
                             )
                         }
                     }
+                    batch_inflight_requests.push((desc_chain.head_index(), request));
+                } else {
+                    self.inflight_requests
+                        .push_back((desc_chain.head_index(), request));
                 }
-                batch_inflight_requests.push((desc_chain.head_index(), request));
             } else {
                 let status = match result {
                     Ok(_) => VIRTIO_BLK_S_OK,
@@ -380,6 +447,9 @@ impl BlockEpollHandler {
     }
 
     fn process_queue_complete(&mut self) -> Result<()> {
+        if self.needs_reset() {
+            return Ok(());
+        }
         let mem = self.mem.memory();
         let mut read_bytes = Wrapping(0);
         let mut write_bytes = Wrapping(0);
@@ -391,7 +461,9 @@ impl BlockEpollHandler {
 
             let mut request = self.find_inflight_request(desc_index)?;
 
-            request.complete_async().map_err(Error::RequestCompleting)?;
+            request
+                .complete_async(&mem)
+                .map_err(Error::RequestCompleting)?;
 
             let latency = request.start.elapsed().as_micros() as u64;
             let read_ops_last = self.counters.read_ops.load(Ordering::Relaxed);
@@ -662,6 +734,7 @@ pub struct Block {
     serial: Vec<u8>,
     queue_affinity: BTreeMap<u16, Vec<usize>>,
     disable_sector0_writes: bool,
+    device_status: Arc<AtomicU8>,
 }
 
 #[derive(Serialize, Deserialize)]
@@ -807,6 +880,7 @@ impl Block {
             serial,
             queue_affinity,
             disable_sector0_writes,
+            device_status: Arc::new(AtomicU8::new(0)),
         })
     }
 
@@ -998,12 +1072,14 @@ impl VirtioDevice for Block {
         self.update_writeback();
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        mut queues: Vec<(usize, Queue, EventFd)>,
+            mut queues,
-    ) -> ActivateResult {
+            device_status,
+        } = context;
+        self.device_status = device_status;
         // See if the guest didn't ack the device being read-only.
         // If so, warn and pretend it did.
         let original_acked_features = self.common.acked_features;
@@ -1059,6 +1135,7 @@ impl VirtioDevice for Block {
                 host_cpus: self.queue_affinity.get(&queue_idx).cloned(),
                 acked_features: self.common.acked_features,
                 disable_sector0_writes: self.disable_sector0_writes,
+                device_status: self.device_status.clone(),
             };
 
             let paused = self.common.paused.clone();

virtio-devices/src/console.rs

@@ -703,12 +703,13 @@ impl VirtioDevice for Console {
         self.read_config_from_slice(self.config.lock().unwrap().as_slice(), offset, data);
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        mut queues: Vec<(usize, Queue, EventFd)>,
+            mut queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.common.activate(&queues, interrupt_cb.clone())?;
         self.resizer
             .acked_features

virtio-devices/src/device.rs

@@ -9,7 +9,7 @@
 use std::collections::HashMap;
 use std::io::Write;
 use std::num::Wrapping;
-use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::atomic::{AtomicBool, AtomicU8, Ordering};
 use std::sync::{Arc, Barrier};
 use std::thread;
 
@@ -53,6 +53,13 @@ pub struct VirtioSharedMemoryList {
     pub region_list: Vec<VirtioSharedMemory>,
 }
 
+pub struct ActivationContext {
+    pub mem: GuestMemoryAtomic<GuestMemoryMmap>,
+    pub interrupt_cb: Arc<dyn VirtioInterrupt>,
+    pub queues: Vec<(usize, Queue, EventFd)>,
+    pub device_status: Arc<AtomicU8>,
+}
+
 /// Trait for virtio devices to be driven by a virtio transport.
 ///
 /// The lifecycle of a virtio device is to be moved to a virtio transport, which will then query the
@@ -94,12 +101,7 @@ pub trait VirtioDevice: Send {
     }
 
     /// Activates this device for real usage.
-    fn activate(
+    fn activate(&mut self, context: ActivationContext) -> ActivateResult;
-        &mut self,
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
-        interrupt_evt: Arc<dyn VirtioInterrupt>,
-        queues: Vec<(usize, Queue, EventFd)>,
-    ) -> ActivateResult;
 
     /// Optionally deactivates this device and returns ownership of the guest memory map, interrupt
     /// event, and queue events.

virtio-devices/src/iommu.rs

@@ -1075,12 +1075,13 @@ impl VirtioDevice for Iommu {
         self.update_bypass();
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        mut queues: Vec<(usize, Queue, EventFd)>,
+            mut queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.common.activate(&queues, interrupt_cb.clone())?;
         let (kill_evt, pause_evt) = self.common.dup_eventfds();
 

virtio-devices/src/lib.rs

@@ -42,8 +42,8 @@ pub use self::balloon::Balloon;
 pub use self::block::{Block, BlockState};
 pub use self::console::{Console, ConsoleResizer, Endpoint};
 pub use self::device::{
-    DmaRemapping, VirtioCommon, VirtioDevice, VirtioInterrupt, VirtioInterruptType,
+    ActivationContext, DmaRemapping, VirtioCommon, VirtioDevice, VirtioInterrupt,
-    VirtioSharedMemoryList,
+    VirtioInterruptType, VirtioSharedMemoryList,
 };
 pub use self::epoll_helper::{
     EPOLL_HELPER_EVENT_LAST, EpollHelper, EpollHelperError, EpollHelperHandler,
@@ -66,6 +66,7 @@ const DEVICE_ACKNOWLEDGE: u32 = 0x01;
 const DEVICE_DRIVER: u32 = 0x02;
 const DEVICE_DRIVER_OK: u32 = 0x04;
 const DEVICE_FEATURES_OK: u32 = 0x08;
+const DEVICE_NEEDS_RESET: u32 = 0x40;
 const DEVICE_FAILED: u32 = 0x80;
 
 const VIRTIO_F_RING_INDIRECT_DESC: u32 = 28;

virtio-devices/src/mem.rs

@@ -950,12 +950,13 @@ impl VirtioDevice for Mem {
         self.read_config_from_slice(self.config.lock().unwrap().as_slice(), offset, data);
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        mut queues: Vec<(usize, Queue, EventFd)>,
+            mut queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.common.activate(&queues, interrupt_cb.clone())?;
         let (kill_evt, pause_evt) = self.common.dup_eventfds();
 

virtio-devices/src/net.rs

@@ -10,13 +10,13 @@ use std::net::IpAddr;
 use std::num::Wrapping;
 use std::ops::Deref;
 use std::os::unix::io::{AsRawFd, RawFd};
-use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::atomic::{AtomicBool, AtomicU8, Ordering};
 use std::sync::{Arc, Barrier};
 use std::{result, thread};
 
 use anyhow::anyhow;
 use event_monitor::event;
-use log::{debug, error, info};
+use log::{debug, error, info, warn};
 #[cfg(not(fuzzing))]
 use net_util::virtio_features_to_tap_offload;
 use net_util::{
@@ -179,6 +179,7 @@ struct NetEpollHandler {
     // a restore as the vCPU thread isn't ready to handle the interrupt. This causes
     // issues when combined with VIRTIO_RING_F_EVENT_IDX interrupt suppression.
     driver_awake: bool,
+    device_status: Arc<AtomicU8>,
 }
 
 impl NetEpollHandler {
@@ -192,6 +193,9 @@ impl NetEpollHandler {
     }
 
     fn handle_rx_event(&mut self) -> result::Result<(), DeviceError> {
+        if self.needs_reset() {
+            return Ok(());
+        }
         let queue_evt = &self.queue_evt_pair.0;
         if let Err(e) = queue_evt.read() {
             error!("Failed to get rx queue event: {e:?}");
@@ -220,13 +224,43 @@ impl NetEpollHandler {
         Ok(())
     }
 
+    fn handle_queue_iterator_error(&mut self, err: &virtio_queue::Error) {
+        // The guest submitted a corrupted VirtQ request, and the error
+        // was logged during queue processing. We cannot just ignore the
+        // error, as the guest could continue spamming the VMM with bad
+        // requests, triggering excessive error logging. So we mark
+        // the device "NEEDS_RESET", effectively stopping all request
+        // processing (see self.needs_reset() usage) until the guest
+        // resets and reactivates the device.
+
+        warn!(
+            "Corrupted request detected (virtqueue error: {err:?}). \
+Setting device status to 'NEEDS_RESET' and stopping processing queues until reset."
+        );
+
+        self.device_status
+            .fetch_or(crate::DEVICE_NEEDS_RESET as u8, Ordering::SeqCst);
+
+        // Let the guest know that the device status has changed.
+        if let Err(e) = self.interrupt_cb.trigger(VirtioInterruptType::Config) {
+            error!("Failed to signal config interrupt: {e:?}");
+        }
+    }
+
     fn process_tx(&mut self) -> result::Result<(), DeviceError> {
-        if self
+        if self.needs_reset() {
+            return Ok(());
+        }
+        let res = self
             .net
-            .process_tx(&self.mem.memory(), &mut self.queue_pair.1)
+            .process_tx(&self.mem.memory(), &mut self.queue_pair.1);
-            .map_err(DeviceError::NetQueuePair)?
+
-            || !self.driver_awake
+        if let Err(net_util::NetQueuePairError::QueueIteratorFailed(err)) = res {
-        {
+            self.handle_queue_iterator_error(&err);
+            return Ok(());
+        }
+
+        if res.map_err(DeviceError::NetQueuePair)? || !self.driver_awake {
             self.signal_used_queue(self.queue_index_base + 1)?;
             debug!("Signalling TX queue");
         } else {
@@ -250,12 +284,19 @@ impl NetEpollHandler {
     }
 
     fn handle_rx_tap_event(&mut self) -> result::Result<(), DeviceError> {
-        if self
+        if self.needs_reset() {
+            return Ok(());
+        }
+        let res = self
             .net
-            .process_rx(&self.mem.memory(), &mut self.queue_pair.0)
+            .process_rx(&self.mem.memory(), &mut self.queue_pair.0);
-            .map_err(DeviceError::NetQueuePair)?
+
-            || !self.driver_awake
+        if let Err(net_util::NetQueuePairError::QueueIteratorFailed(err)) = res {
-        {
+            self.handle_queue_iterator_error(&err);
+            return Ok(());
+        }
+
+        if res.map_err(DeviceError::NetQueuePair)? || !self.driver_awake {
             self.signal_used_queue(self.queue_index_base)?;
             debug!("Signalling RX queue");
         } else {
@@ -305,6 +346,10 @@ impl NetEpollHandler {
 
         Ok(())
     }
+
+    fn needs_reset(&self) -> bool {
+        (self.device_status.load(Ordering::Acquire) & crate::DEVICE_NEEDS_RESET as u8) != 0
+    }
 }
 
 impl EpollHelperHandler for NetEpollHandler {
@@ -414,6 +459,7 @@ pub struct Net {
     seccomp_action: SeccompAction,
     rate_limiter_config: Option<RateLimiterConfig>,
     exit_evt: EventFd,
+    device_status: Arc<AtomicU8>,
 }
 
 #[derive(Serialize, Deserialize)]
@@ -535,6 +581,7 @@ impl Net {
             seccomp_action,
             rate_limiter_config,
             exit_evt,
+            device_status: Arc::new(AtomicU8::new(0)),
         })
     }
 
@@ -693,12 +740,14 @@ impl VirtioDevice for Net {
         self.read_config_from_slice(self.config.as_slice(), offset, data);
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        mut queues: Vec<(usize, Queue, EventFd)>,
+            mut queues,
-    ) -> ActivateResult {
+            device_status,
+        } = context;
+        self.device_status = device_status;
         self.common.activate(&queues, interrupt_cb.clone())?;
 
         let num_queues = queues.len();
@@ -803,6 +852,7 @@ impl VirtioDevice for Net {
                 kill_evt,
                 pause_evt,
                 driver_awake: false,
+                device_status: self.device_status.clone(),
             };
 
             let paused = self.common.paused.clone();

virtio-devices/src/pmem.rs

@@ -377,12 +377,13 @@ impl VirtioDevice for Pmem {
         self.read_config_from_slice(self.config.as_slice(), offset, data);
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        mut queues: Vec<(usize, Queue, EventFd)>,
+            mut queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.common.activate(&queues, interrupt_cb.clone())?;
         let (kill_evt, pause_evt) = self.common.dup_eventfds();
         if let Some(disk) = self.disk.as_ref() {

virtio-devices/src/rng.rs

@@ -244,12 +244,13 @@ impl VirtioDevice for Rng {
         self.common.ack_features(value);
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        mut queues: Vec<(usize, Queue, EventFd)>,
+            mut queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.common.activate(&queues, interrupt_cb.clone())?;
         let (kill_evt, pause_evt) = self.common.dup_eventfds();
 

virtio-devices/src/transport/pci_common_config.rs

@@ -6,7 +6,7 @@
 //
 // SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
 
-use std::sync::atomic::{AtomicU16, Ordering};
+use std::sync::atomic::{AtomicU8, AtomicU16, Ordering};
 use std::sync::{Arc, Mutex};
 
 use byteorder::{ByteOrder, LittleEndian};
@@ -125,7 +125,7 @@ pub fn get_vring_size(t: VringType, queue_size: u16) -> u64 {
 ///    le64 queue_used;                // 0x30 // read-write
 pub struct VirtioPciCommonConfig {
     pub access_platform: Option<Arc<dyn AccessPlatform>>,
-    pub driver_status: u8,
+    pub driver_status: Arc<AtomicU8>,
     pub config_generation: u8,
     pub device_feature_select: u32,
     pub driver_feature_select: u32,
@@ -141,7 +141,7 @@ impl VirtioPciCommonConfig {
     ) -> Self {
         VirtioPciCommonConfig {
             access_platform,
-            driver_status: state.driver_status,
+            driver_status: Arc::new(AtomicU8::new(state.driver_status)),
             config_generation: state.config_generation,
             device_feature_select: state.device_feature_select,
             driver_feature_select: state.driver_feature_select,
@@ -153,7 +153,7 @@ impl VirtioPciCommonConfig {
 
     fn state(&self) -> VirtioPciCommonConfigState {
         VirtioPciCommonConfigState {
-            driver_status: self.driver_status,
+            driver_status: self.driver_status.load(Ordering::Acquire),
             config_generation: self.config_generation,
             device_feature_select: self.device_feature_select,
             driver_feature_select: self.driver_feature_select,
@@ -223,7 +223,7 @@ impl VirtioPciCommonConfig {
         debug!("read_common_config_byte: offset 0x{offset:x}");
         // The driver is only allowed to do aligned, properly sized access.
         match offset {
-            0x14 => self.driver_status,
+            0x14 => self.driver_status.load(Ordering::Acquire),
             0x15 => self.config_generation,
             _ => {
                 warn!("invalid virtio config byte read: 0x{offset:x}");
@@ -235,7 +235,7 @@ impl VirtioPciCommonConfig {
     fn write_common_config_byte(&mut self, offset: u64, value: u8) {
         debug!("write_common_config_byte: offset 0x{offset:x}");
         match offset {
-            0x14 => self.driver_status = value,
+            0x14 => self.driver_status.store(value, Ordering::Release),
             _ => {
                 warn!("invalid virtio config byte write: 0x{offset:x}");
             }
@@ -404,11 +404,8 @@ impl Snapshottable for VirtioPciCommonConfig {
 
 #[cfg(test)]
 mod unit_tests {
-    use vm_memory::GuestMemoryAtomic;
-    use vmm_sys_util::eventfd::EventFd;
-
     use super::*;
-    use crate::{ActivateResult, GuestMemoryMmap, VirtioInterrupt};
+    use crate::{ActivateResult, ActivationContext};
 
     struct DummyDevice(u32);
     const QUEUE_SIZE: u16 = 256;
@@ -421,12 +418,7 @@ mod unit_tests {
         fn queue_max_sizes(&self) -> &[u16] {
             QUEUE_SIZES
         }
-        fn activate(
+        fn activate(&mut self, _context: ActivationContext) -> ActivateResult {
-            &mut self,
-            _mem: GuestMemoryAtomic<GuestMemoryMmap>,
-            _interrupt_evt: Arc<dyn VirtioInterrupt>,
-            _queues: Vec<(usize, Queue, EventFd)>,
-        ) -> ActivateResult {
             Ok(())
         }
 
@@ -445,7 +437,7 @@ mod unit_tests {
     fn write_base_regs() {
         let mut regs = VirtioPciCommonConfig {
             access_platform: None,
-            driver_status: 0xaa,
+            driver_status: Arc::new(AtomicU8::new(0xaa)),
             config_generation: 0x55,
             device_feature_select: 0x0,
             driver_feature_select: 0x0,

virtio-devices/src/transport/pci_device.rs

@@ -10,7 +10,7 @@ use std::any::Any;
 use std::cmp;
 use std::io::Write;
 use std::ops::Deref;
-use std::sync::atomic::{AtomicBool, AtomicU16, AtomicUsize, Ordering};
+use std::sync::atomic::{AtomicBool, AtomicU8, AtomicU16, AtomicUsize, Ordering};
 use std::sync::{Arc, Barrier, Mutex};
 
 use anyhow::anyhow;
@@ -288,15 +288,18 @@ pub struct VirtioPciDeviceActivator {
     queues: Option<Vec<(usize, Queue, EventFd)>>,
     barrier: Option<Arc<Barrier>>,
     id: String,
+    status: Arc<AtomicU8>,
 }
 
 impl VirtioPciDeviceActivator {
-    pub fn activate(&mut self) -> ActivateResult {
+    pub fn activate(mut self) -> ActivateResult {
-        self.device.lock().unwrap().activate(
+        let mut locked_device = self.device.lock().unwrap();
-            self.memory.take().unwrap(),
+        locked_device.activate(crate::device::ActivationContext {
-            self.interrupt.take().unwrap(),
+            mem: self.memory.take().unwrap(),
-            self.queues.take().unwrap(),
+            interrupt_cb: self.interrupt.take().unwrap(),
-        )?;
+            queues: self.queues.take().unwrap(),
+            device_status: self.status,
+        })?;
         self.device_activated.store(true, Ordering::SeqCst);
 
         if let Some(barrier) = self.barrier.take() {
@@ -641,13 +644,13 @@ impl VirtioPciDevice {
     fn is_driver_ready(&self) -> bool {
         let ready_bits =
             (DEVICE_ACKNOWLEDGE | DEVICE_DRIVER | DEVICE_DRIVER_OK | DEVICE_FEATURES_OK) as u8;
-        self.common_config.driver_status == ready_bits
+        let driver_status = self.common_config.driver_status.load(Ordering::SeqCst);
-            && self.common_config.driver_status & DEVICE_FAILED as u8 == 0
+        driver_status == ready_bits && (driver_status & DEVICE_FAILED as u8) == 0
     }
 
     /// Determines if the driver has requested the device (re)init / reset itself
     fn is_driver_init(&self) -> bool {
-        self.common_config.driver_status == DEVICE_INIT as u8
+        self.common_config.driver_status.load(Ordering::SeqCst) == DEVICE_INIT as u8
     }
 
     pub fn config_bar_addr(&self) -> u64 {
@@ -801,6 +804,7 @@ impl VirtioPciDevice {
             device_activated: self.device_activated.clone(),
             barrier,
             id: self.id.clone(),
+            status: self.common_config.driver_status.clone(),
         }
     }
 
@@ -1219,7 +1223,9 @@ impl PciDevice for VirtioPciDevice {
                 self.common_config.queue_select = 0;
             } else {
                 error!("Attempt to reset device when not implemented in underlying device");
-                self.common_config.driver_status = crate::DEVICE_FAILED as u8;
+                self.common_config
+                    .driver_status
+                    .store(crate::DEVICE_FAILED as u8, Ordering::SeqCst);
             }
         }
 

virtio-devices/src/vdpa.rs

@@ -428,12 +428,13 @@ impl VirtioDevice for Vdpa {
         }
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        virtio_interrupt: Arc<dyn VirtioInterrupt>,
+            interrupt_cb: virtio_interrupt,
-        queues: Vec<(usize, Queue, EventFd)>,
+            queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.activate_vdpa(&mem.memory(), virtio_interrupt.as_ref(), &queues)
             .map_err(ActivateError::ActivateVdpa)?;
 

virtio-devices/src/vhost_user/blk.rs

@@ -19,7 +19,6 @@ use virtio_bindings::virtio_blk::{
     VIRTIO_BLK_F_GEOMETRY, VIRTIO_BLK_F_MQ, VIRTIO_BLK_F_RO, VIRTIO_BLK_F_SEG_MAX,
     VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_WRITE_ZEROES,
 };
-use virtio_queue::Queue;
 use vm_memory::{ByteValued, GuestMemoryAtomic};
 use vm_migration::protocol::MemoryRangeTable;
 use vm_migration::{Migratable, MigratableError, Pausable, Snapshot, Snapshottable, Transportable};
@@ -279,12 +278,13 @@ impl VirtioDevice for Blk {
         }
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        queues: Vec<(usize, Queue, EventFd)>,
+            queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.common.activate(&queues, interrupt_cb.clone())?;
         self.guest_memory = Some(mem.clone());
 

virtio-devices/src/vhost_user/fs.rs

@@ -12,7 +12,6 @@ use serde::{Deserialize, Serialize};
 use serde_with::{Bytes, serde_as};
 use vhost::vhost_user::message::{VhostUserProtocolFeatures, VhostUserVirtioFeatures};
 use vhost::vhost_user::{FrontendReqHandler, VhostUserFrontend, VhostUserFrontendReqHandler};
-use virtio_queue::Queue;
 use vm_device::UserspaceMapping;
 use vm_memory::{ByteValued, GuestMemoryAtomic};
 use vm_migration::protocol::MemoryRangeTable;
@@ -261,12 +260,13 @@ impl VirtioDevice for Fs {
         self.read_config_from_slice(self.config.as_slice(), offset, data);
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        queues: Vec<(usize, Queue, EventFd)>,
+            queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.common.activate(&queues, interrupt_cb.clone())?;
         self.guest_memory = Some(mem.clone());
 

virtio-devices/src/vhost_user/net.rs

@@ -19,7 +19,7 @@ use virtio_bindings::virtio_net::{
     VIRTIO_NET_F_MAC, VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_MTU,
 };
 use virtio_bindings::virtio_ring::VIRTIO_RING_F_EVENT_IDX;
-use virtio_queue::{Queue, QueueT};
+use virtio_queue::QueueT;
 use vm_memory::{ByteValued, GuestMemoryAtomic};
 use vm_migration::protocol::MemoryRangeTable;
 use vm_migration::{Migratable, MigratableError, Pausable, Snapshot, Snapshottable, Transportable};
@@ -288,12 +288,13 @@ impl VirtioDevice for Net {
         self.read_config_from_slice(self.config.as_slice(), offset, data);
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        mut queues: Vec<(usize, Queue, EventFd)>,
+            mut queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.common.activate(&queues, interrupt_cb.clone())?;
         self.guest_memory = Some(mem.clone());
 

virtio-devices/src/vsock/device.rs

@@ -435,12 +435,13 @@ where
         }
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        queues: Vec<(usize, Queue, EventFd)>,
+            queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.common.activate(&queues, interrupt_cb.clone())?;
         let (kill_evt, pause_evt) = self.common.dup_eventfds();
 
@@ -593,9 +594,12 @@ mod unit_tests {
         let memory = GuestMemoryAtomic::new(ctx.mem.clone());
 
         // Test a bad activation.
-        let bad_activate =
+        let bad_activate = ctx.device.activate(crate::device::ActivationContext {
-            ctx.device
+            mem: memory.clone(),
-                .activate(memory.clone(), Arc::new(NoopVirtioInterrupt {}), Vec::new());
+            interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
+            queues: Vec::new(),
+            device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+        });
         match bad_activate {
             Err(ActivateError::BadActivate) => (),
             other => panic!("{other:?}"),
@@ -603,10 +607,10 @@ mod unit_tests {
 
         // Test a correct activation.
         ctx.device
-            .activate(
+            .activate(crate::device::ActivationContext {
-                memory,
+                mem: memory,
-                Arc::new(NoopVirtioInterrupt {}),
+                interrupt_cb: Arc::new(NoopVirtioInterrupt {}),
-                vec![
+                queues: vec![
                     (
                         0,
                         Queue::new(256).unwrap(),
@@ -623,7 +627,8 @@ mod unit_tests {
                         EventFd::new(EFD_NONBLOCK).unwrap(),
                     ),
                 ],
-            )
+                device_status: Arc::new(std::sync::atomic::AtomicU8::new(0)),
+            })
             .unwrap();
     }
 

virtio-devices/src/vsock/unix/muxer.rs

@@ -407,9 +407,11 @@ impl VsockMuxer {
             Some(EpollListener::HostSock) => {
                 if self.conn_map.len() == defs::MAX_CONNECTIONS {
                     // If we're already maxed-out on connections, we'll just accept and
-                    // immediately discard this potentially new one.
+                    // immediately discard this potentially new one. Dropping the returned
+                    // `UnixStream` closes the new connection; we don't care if `accept()`
+                    // itself failed.
                     warn!("vsock: connection limit reached; refusing new host connection");
-                    self.host_sock.accept().map(|_| 0).unwrap_or(0);
+                    let _ = self.host_sock.accept();
                     return;
                 }
                 self.host_sock

virtio-devices/src/vsock/unix/muxer_killq.rs

@@ -110,6 +110,10 @@ impl MuxerKillQ {
     /// This will succeed and return a connection key, only if the connection at the front of
     /// the queue has expired. Otherwise, `None` is returned.
     ///
+    // `VecDeque::pop_front_if` is unstable on the project MSRV; allow the
+    // beta clippy lint that asks for it. `unknown_lints` is needed because
+    // the lint does not exist on stable clippy.
+    #[allow(unknown_lints, clippy::manual_pop_if)]
     pub fn pop(&mut self) -> Option<ConnMapKey> {
         if let Some(item) = self.q.front()
             && Instant::now() > item.kill_time

virtio-devices/src/watchdog.rs

@@ -326,12 +326,13 @@ impl VirtioDevice for Watchdog {
         self.common.ack_features(value);
     }
 
-    fn activate(
+    fn activate(&mut self, context: crate::device::ActivationContext) -> ActivateResult {
-        &mut self,
+        let crate::device::ActivationContext {
-        mem: GuestMemoryAtomic<GuestMemoryMmap>,
+            mem,
-        interrupt_cb: Arc<dyn VirtioInterrupt>,
+            interrupt_cb,
-        mut queues: Vec<(usize, Queue, EventFd)>,
+            mut queues,
-    ) -> ActivateResult {
+            ..
+        } = context;
         self.common.activate(&queues, interrupt_cb.clone())?;
         let (kill_evt, pause_evt) = self.common.dup_eventfds();
 

vmm/src/api/openapi/cloud-hypervisor.yaml

@@ -948,7 +948,8 @@ components:
           type: boolean
           default: true
         image_type:
-          type: enum ["FixedVhd", "Qcow2", "Raw", "Vhdx"]
+          type: string
+          enum: [FixedVhd, Qcow2, Raw, Vhdx, Unknown]
 
 
     NetConfig:

vmm/src/device_manager.rs

@@ -4477,7 +4477,7 @@ impl DeviceManager {
     }
 
     pub fn activate_virtio_devices(&self) -> DeviceManagerResult<()> {
-        for mut activator in self.pending_activations.lock().unwrap().drain(..) {
+        for activator in self.pending_activations.lock().unwrap().drain(..) {
             activator
                 .activate()
                 .map_err(DeviceManagerError::VirtioActivate)?;

vmm/src/gdb.rs

@@ -484,7 +484,7 @@ impl run_blocking::BlockingEventLoop for GdbEventLoop {
                 }
             }
 
-            if conn.peek().map(|b| b.is_some()).unwrap_or(true) {
+            if conn.peek().map_or(true, |b| b.is_some()) {
                 let byte = conn
                     .read()
                     .map_err(run_blocking::WaitForStopReasonError::Connection)?;

vmm/src/igvm/igvm_loader.rs

@@ -433,7 +433,7 @@ pub fn load_igvm(
         let mut now = Instant::now();
 
         // Sort the gpas to group them by the page type
-        gpas.sort_by(|a, b| a.gpa.cmp(&b.gpa));
+        gpas.sort_by_key(|a| a.gpa);
 
         let gpas_grouped = gpas
             .iter()

vmm/src/lib.rs

@@ -735,22 +735,20 @@ impl Vmm {
 
         for signal in signals.forever() {
             match signal {
-                SIGTERM | SIGINT => {
+                SIGTERM | SIGINT if exit_evt.write(1).is_err() => {
-                    if exit_evt.write(1).is_err() {
+                    // Resetting the terminal is usually done as the VMM exits
-                        // Resetting the terminal is usually done as the VMM exits
+                    if let Ok(lock) = original_termios_opt.lock() {
-                        if let Ok(lock) = original_termios_opt.lock() {
+                        if let Some(termios) = *lock {
-                            if let Some(termios) = *lock {
+                            // SAFETY: FFI call
-                                // SAFETY: FFI call
+                            let _ = unsafe {
-                                let _ = unsafe {
+                                tcsetattr(stdout().lock().as_raw_fd(), TCSANOW, &termios)
-                                    tcsetattr(stdout().lock().as_raw_fd(), TCSANOW, &termios)
+                            };
-                                };
-                            }
-                        } else {
-                            warn!("Failed to lock original termios");
                         }
-
+                    } else {
-                        std::process::exit(1);
+                        warn!("Failed to lock original termios");
                     }
+
+                    std::process::exit(1);
                 }
                 _ => (),
             }

vmm/src/serial_manager.rs

@@ -132,33 +132,29 @@ impl SerialManager {
 
         let in_fd = match output {
             ConsoleOutput::Pty(ref fd) => fd.as_raw_fd(),
-            ConsoleOutput::Tty(_) => {
+            // If running on an interactive TTY then accept input.
-                // If running on an interactive TTY then accept input
+            // SAFETY: trivially safe
-                // SAFETY: trivially safe
+            ConsoleOutput::Tty(_) if unsafe { libc::isatty(libc::STDIN_FILENO) == 1 } => {
-                if unsafe { libc::isatty(libc::STDIN_FILENO) == 1 } {
+                // SAFETY: STDIN_FILENO is a valid fd
-                    // SAFETY: STDIN_FILENO is a valid fd
+                let fd = unsafe { libc::dup(libc::STDIN_FILENO) };
-                    let fd = unsafe { libc::dup(libc::STDIN_FILENO) };
+                if fd == -1 {
-                    if fd == -1 {
+                    return Err(Error::DupFd(std::io::Error::last_os_error()));
-                        return Err(Error::DupFd(std::io::Error::last_os_error()));
-                    }
-                    // SAFETY: fd is valid and owned by us
-                    let stdin_clone = unsafe { File::from_raw_fd(fd) };
-                    // SAFETY: FFI calls with correct arguments
-                    let ret = unsafe {
-                        let mut flags = libc::fcntl(stdin_clone.as_raw_fd(), libc::F_GETFL);
-                        flags |= libc::O_NONBLOCK;
-                        libc::fcntl(stdin_clone.as_raw_fd(), libc::F_SETFL, flags)
-                    };
-
-                    if ret < 0 {
-                        return Err(Error::SetNonBlocking(std::io::Error::last_os_error()));
-                    }
-
-                    output = ConsoleOutput::Tty(Arc::new(stdin_clone));
-                    fd
-                } else {
-                    return Ok(None);
                 }
+                // SAFETY: fd is valid and owned by us
+                let stdin_clone = unsafe { File::from_raw_fd(fd) };
+                // SAFETY: FFI calls with correct arguments
+                let ret = unsafe {
+                    let mut flags = libc::fcntl(stdin_clone.as_raw_fd(), libc::F_GETFL);
+                    flags |= libc::O_NONBLOCK;
+                    libc::fcntl(stdin_clone.as_raw_fd(), libc::F_SETFL, flags)
+                };
+
+                if ret < 0 {
+                    return Err(Error::SetNonBlocking(std::io::Error::last_os_error()));
+                }
+
+                output = ConsoleOutput::Tty(Arc::new(stdin_clone));
+                fd
             }
             ConsoleOutput::Socket(ref fd) => {
                 if let Some(path_in_socket) = socket {