Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into stagingHEADstagingmaster

* futex: support Windows
* qemu-thread: Avoid futex abstraction for non-Linux
* migration, hw/display/apple-gfx: replace QemuSemaphore with QemuEvent
* rust: bindings for Error
* hpet, rust/hpet: return errors from realize if properties are incorrect
* rust/hpet: Drop BqlCell wrapper for num_timers
* target/i386: Emulate ftz and denormal flag bits correctly
* i386/kvm: Prefault memory on page state change

# -----BEGIN PGP SIGNATURE-----
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# =Vs6V
# -----END PGP SIGNATURE-----
# gpg: Signature made Fri 06 Jun 2025 08:33:12 EDT
# gpg:                using RSA key F13338574B662389866C7682BFFBD25F78C7AE83
# gpg:                issuer "pbonzini@redhat.com"
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [full]
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>" [full]
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (31 commits)
  tests/tcg/x86_64/fma: add test for exact-denormal output
  target/i386: Wire up MXCSR.DE and FPUS.DE correctly
  target/i386: Use correct type for get_float_exception_flags() values
  target/i386: Detect flush-to-zero after rounding
  hw/display/apple-gfx: Replace QemuSemaphore with QemuEvent
  migration/postcopy: Replace QemuSemaphore with QemuEvent
  migration/colo: Replace QemuSemaphore with QemuEvent
  migration: Replace QemuSemaphore with QemuEvent
  qemu-thread: Document QemuEvent
  qemu-thread: Use futex if available for QemuLockCnt
  qemu-thread: Use futex for QemuEvent on Windows
  qemu-thread: Avoid futex abstraction for non-Linux
  qemu-thread: Replace __linux__ with CONFIG_LINUX
  futex: Support Windows
  futex: Check value after qemu_futex_wait()
  i386/kvm: Prefault memory on page state change
  rust: make TryFrom macro more resilient
  docs: update Rust module status
  rust/hpet: Drop BqlCell wrapper for num_timers
  rust/hpet: return errors from realize if properties are incorrect
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

13 files changed, 492 insertions, 48 deletions

diff --git a/rust/Cargo.lock b/rust/Cargo.lock
index bccfe85..b785c71 100644
--- a/rust/Cargo.lock
+++ b/rust/Cargo.lock
@@ -3,6 +3,12 @@
 version = 3
 
 [[package]]
+name = "anyhow"
+version = "1.0.98"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e16d2d3311acee920a9eb8d33b8cbc1787ce4a264e85f964c2404b969bdcd487"
+
+[[package]]
 name = "arbitrary-int"
 version = "1.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -45,6 +51,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3dca9240753cf90908d7e4aac30f630662b02aebaa1b58a3cadabdb23385b58b"
 
 [[package]]
+name = "foreign"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "17ca1b5be8c9d320daf386f1809c7acc0cb09accbae795c2001953fa50585846"
+dependencies = [
+ "libc",
+]
+
+[[package]]
 name = "hpet"
 version = "0.1.0"
 dependencies = [
@@ -114,6 +129,8 @@ dependencies = [
 name = "qemu_api"
 version = "0.1.0"
 dependencies = [
+ "anyhow",
+ "foreign",
  "libc",
  "qemu_api_macros",
 ]
diff --git a/rust/Cargo.toml b/rust/Cargo.toml
index fd4c2fb..0868e1b 100644
--- a/rust/Cargo.toml
+++ b/rust/Cargo.toml
@@ -67,6 +67,7 @@ missing_safety_doc = "deny"
 mut_mut = "deny"
 needless_bitwise_bool = "deny"
 needless_pass_by_ref_mut = "deny"
+needless_update = "deny"
 no_effect_underscore_binding = "deny"
 option_option = "deny"
 or_fun_call = "deny"
diff --git a/rust/hw/char/pl011/src/device.rs b/rust/hw/char/pl011/src/device.rs
index 0501fa5..be8387f 100644
--- a/rust/hw/char/pl011/src/device.rs
+++ b/rust/hw/char/pl011/src/device.rs
@@ -175,7 +175,7 @@ impl DeviceImpl for PL011State {
     fn vmsd() -> Option<&'static VMStateDescription> {
         Some(&device_class::VMSTATE_PL011)
     }
-    const REALIZE: Option<fn(&Self)> = Some(Self::realize);
+    const REALIZE: Option<fn(&Self) -> qemu_api::Result<()>> = Some(Self::realize);
 }
 
 impl ResettablePhasesImpl for PL011State {
@@ -619,9 +619,10 @@ impl PL011State {
         }
     }
 
-    fn realize(&self) {
+    fn realize(&self) -> qemu_api::Result<()> {
         self.char_backend
             .enable_handlers(self, Self::can_receive, Self::receive, Self::event);
+        Ok(())
     }
 
     fn reset_hold(&self, _type: ResetType) {
diff --git a/rust/hw/timer/hpet/src/device.rs b/rust/hw/timer/hpet/src/device.rs
index e3ba62b..735b2fb 100644
--- a/rust/hw/timer/hpet/src/device.rs
+++ b/rust/hw/timer/hpet/src/device.rs
@@ -12,7 +12,7 @@ use std::{
 use qemu_api::{
     bindings::{
         address_space_memory, address_space_stl_le, qdev_prop_bit, qdev_prop_bool,
-        qdev_prop_uint32, qdev_prop_uint8,
+        qdev_prop_uint32, qdev_prop_usize,
     },
     cell::{BqlCell, BqlRefCell},
     irq::InterruptSource,
@@ -36,9 +36,9 @@ use crate::fw_cfg::HPETFwConfig;
 const HPET_REG_SPACE_LEN: u64 = 0x400; // 1024 bytes
 
 /// Minimum recommended hardware implementation.
-const HPET_MIN_TIMERS: u8 = 3;
+const HPET_MIN_TIMERS: usize = 3;
 /// Maximum timers in each timer block.
-const HPET_MAX_TIMERS: u8 = 32;
+const HPET_MAX_TIMERS: usize = 32;
 
 /// Flags that HPETState.flags supports.
 const HPET_FLAG_MSI_SUPPORT_SHIFT: usize = 0;
@@ -561,8 +561,8 @@ pub struct HPETState {
 
     /// HPET timer array managed by this timer block.
     #[doc(alias = "timer")]
-    timers: [BqlRefCell<HPETTimer>; HPET_MAX_TIMERS as usize],
-    num_timers: BqlCell<u8>,
+    timers: [BqlRefCell<HPETTimer>; HPET_MAX_TIMERS],
+    num_timers: usize,
     num_timers_save: BqlCell<u8>,
 
     /// Instance id (HPET timer block ID).
@@ -570,11 +570,6 @@ pub struct HPETState {
 }
 
 impl HPETState {
-    // Get num_timers with `usize` type, which is useful to play with array index.
-    fn get_num_timers(&self) -> usize {
-        self.num_timers.get().into()
-    }
-
     const fn has_msi_flag(&self) -> bool {
         self.flags & (1 << HPET_FLAG_MSI_SUPPORT_SHIFT) != 0
     }
@@ -636,7 +631,7 @@ impl HPETState {
             self.hpet_offset
                 .set(ticks_to_ns(self.counter.get()) - CLOCK_VIRTUAL.get_ns());
 
-            for timer in self.timers.iter().take(self.get_num_timers()) {
+            for timer in self.timers.iter().take(self.num_timers) {
                 let mut t = timer.borrow_mut();
 
                 if t.is_int_enabled() && t.is_int_active() {
@@ -648,7 +643,7 @@ impl HPETState {
             // Halt main counter and disable interrupt generation.
             self.counter.set(self.get_ticks());
 
-            for timer in self.timers.iter().take(self.get_num_timers()) {
+            for timer in self.timers.iter().take(self.num_timers) {
                 timer.borrow_mut().del_timer();
             }
         }
@@ -671,7 +666,7 @@ impl HPETState {
         let new_val = val << shift;
         let cleared = new_val & self.int_status.get();
 
-        for (index, timer) in self.timers.iter().take(self.get_num_timers()).enumerate() {
+        for (index, timer) in self.timers.iter().take(self.num_timers).enumerate() {
             if cleared & (1 << index) != 0 {
                 timer.borrow_mut().update_irq(false);
             }
@@ -724,19 +719,17 @@ impl HPETState {
         }
     }
 
-    fn realize(&self) {
+    fn realize(&self) -> qemu_api::Result<()> {
+        if self.num_timers < HPET_MIN_TIMERS || self.num_timers > HPET_MAX_TIMERS {
+            Err(format!(
+                "hpet.num_timers must be between {HPET_MIN_TIMERS} and {HPET_MAX_TIMERS}"
+            ))?;
+        }
         if self.int_route_cap == 0 {
-            // TODO: Add error binding: warn_report()
-            println!("Hpet's hpet-intcap property not initialized");
+            Err("hpet.hpet-intcap property not initialized")?;
         }
 
-        self.hpet_id.set(HPETFwConfig::assign_hpet_id());
-
-        if self.num_timers.get() < HPET_MIN_TIMERS {
-            self.num_timers.set(HPET_MIN_TIMERS);
-        } else if self.num_timers.get() > HPET_MAX_TIMERS {
-            self.num_timers.set(HPET_MAX_TIMERS);
-        }
+        self.hpet_id.set(HPETFwConfig::assign_hpet_id()?);
 
         self.init_timer();
         // 64-bit General Capabilities and ID Register; LegacyReplacementRoute.
@@ -745,16 +738,17 @@ impl HPETState {
             1 << HPET_CAP_COUNT_SIZE_CAP_SHIFT |
             1 << HPET_CAP_LEG_RT_CAP_SHIFT |
             HPET_CAP_VENDER_ID_VALUE << HPET_CAP_VENDER_ID_SHIFT |
-            ((self.get_num_timers() - 1) as u64) << HPET_CAP_NUM_TIM_SHIFT | // indicate the last timer
+            ((self.num_timers - 1) as u64) << HPET_CAP_NUM_TIM_SHIFT | // indicate the last timer
             (HPET_CLK_PERIOD * FS_PER_NS) << HPET_CAP_CNT_CLK_PERIOD_SHIFT, // 10 ns
         );
 
         self.init_gpio_in(2, HPETState::handle_legacy_irq);
         self.init_gpio_out(from_ref(&self.pit_enabled));
+        Ok(())
     }
 
     fn reset_hold(&self, _type: ResetType) {
-        for timer in self.timers.iter().take(self.get_num_timers()) {
+        for timer in self.timers.iter().take(self.num_timers) {
             timer.borrow_mut().reset();
         }
 
@@ -782,7 +776,7 @@ impl HPETState {
             GlobalRegister::try_from(addr).map(HPETRegister::Global)
         } else {
             let timer_id: usize = ((addr - 0x100) / 0x20) as usize;
-            if timer_id <= self.get_num_timers() {
+            if timer_id < self.num_timers {
                 // TODO: Add trace point - trace_hpet_ram_[read|write]_timer_id(timer_id)
                 TimerRegister::try_from(addr & 0x18)
                     .map(|reg| HPETRegister::Timer(&self.timers[timer_id], reg))
@@ -853,12 +847,12 @@ impl HPETState {
          * also added to the migration stream.  Check that it matches the value
          * that was configured.
          */
-        self.num_timers_save.set(self.num_timers.get());
+        self.num_timers_save.set(self.num_timers as u8);
         0
     }
 
     fn post_load(&self, _version_id: u8) -> i32 {
-        for timer in self.timers.iter().take(self.get_num_timers()) {
+        for timer in self.timers.iter().take(self.num_timers) {
             let mut t = timer.borrow_mut();
 
             t.cmp64 = t.calculate_cmp64(t.get_state().counter.get(), t.cmp);
@@ -883,7 +877,7 @@ impl HPETState {
     }
 
     fn validate_num_timers(&self, _version_id: u8) -> bool {
-        self.num_timers.get() == self.num_timers_save.get()
+        self.num_timers == self.num_timers_save.get().into()
     }
 }
 
@@ -910,7 +904,7 @@ qemu_api::declare_properties! {
         c"timers",
         HPETState,
         num_timers,
-        unsafe { &qdev_prop_uint8 },
+        unsafe { &qdev_prop_usize },
         u8,
         default = HPET_MIN_TIMERS
     ),
@@ -1015,16 +1009,16 @@ const VALIDATE_TIMERS_NAME: &CStr = c"num_timers must match";
 static VMSTATE_HPET: VMStateDescription = VMStateDescription {
     name: c"hpet".as_ptr(),
     version_id: 2,
-    minimum_version_id: 1,
+    minimum_version_id: 2,
     pre_save: Some(hpet_pre_save),
     post_load: Some(hpet_post_load),
     fields: vmstate_fields! {
         vmstate_of!(HPETState, config),
         vmstate_of!(HPETState, int_status),
         vmstate_of!(HPETState, counter),
-        vmstate_of!(HPETState, num_timers_save).with_version_id(2),
+        vmstate_of!(HPETState, num_timers_save),
         vmstate_validate!(HPETState, VALIDATE_TIMERS_NAME, HPETState::validate_num_timers),
-        vmstate_struct!(HPETState, timers[0 .. num_timers], &VMSTATE_HPET_TIMER, BqlRefCell<HPETTimer>, HPETState::validate_num_timers).with_version_id(0),
+        vmstate_struct!(HPETState, timers[0 .. num_timers_save], &VMSTATE_HPET_TIMER, BqlRefCell<HPETTimer>, HPETState::validate_num_timers).with_version_id(0),
     },
     subsections: vmstate_subsections! {
         VMSTATE_HPET_RTC_IRQ_LEVEL,
@@ -1042,7 +1036,7 @@ impl DeviceImpl for HPETState {
         Some(&VMSTATE_HPET)
     }
 
-    const REALIZE: Option<fn(&Self)> = Some(Self::realize);
+    const REALIZE: Option<fn(&Self) -> qemu_api::Result<()>> = Some(Self::realize);
 }
 
 impl ResettablePhasesImpl for HPETState {
diff --git a/rust/hw/timer/hpet/src/fw_cfg.rs b/rust/hw/timer/hpet/src/fw_cfg.rs
index 6c10316..619d662 100644
--- a/rust/hw/timer/hpet/src/fw_cfg.rs
+++ b/rust/hw/timer/hpet/src/fw_cfg.rs
@@ -36,7 +36,7 @@ pub static mut hpet_fw_cfg: HPETFwConfig = HPETFwConfig {
 };
 
 impl HPETFwConfig {
-    pub(crate) fn assign_hpet_id() -> usize {
+    pub(crate) fn assign_hpet_id() -> Result<usize, &'static str> {
         assert!(bql_locked());
         // SAFETY: all accesses go through these methods, which guarantee
         // that the accesses are protected by the BQL.
@@ -48,13 +48,12 @@ impl HPETFwConfig {
         }
 
         if fw_cfg.count == 8 {
-            // TODO: Add error binding: error_setg()
-            panic!("Only 8 instances of HPET is allowed");
+            Err("Only 8 instances of HPET are allowed")?;
         }
 
         let id: usize = fw_cfg.count.into();
         fw_cfg.count += 1;
-        id
+        Ok(id)
     }
 
     pub(crate) fn update_hpet_cfg(hpet_id: usize, timer_block_id: u32, address: u64) {
diff --git a/rust/meson.build b/rust/meson.build
index b1b3315..99ae795 100644
--- a/rust/meson.build
+++ b/rust/meson.build
@@ -1,9 +1,13 @@
+subproject('anyhow-1-rs', required: true)
 subproject('bilge-0.2-rs', required: true)
 subproject('bilge-impl-0.2-rs', required: true)
+subproject('foreign-0.3-rs', required: true)
 subproject('libc-0.2-rs', required: true)
 
+anyhow_rs = dependency('anyhow-1-rs')
 bilge_rs = dependency('bilge-0.2-rs')
 bilge_impl_rs = dependency('bilge-impl-0.2-rs')
+foreign_rs = dependency('foreign-0.3-rs')
 libc_rs = dependency('libc-0.2-rs')
 
 subproject('proc-macro2-1-rs', required: true)
diff --git a/rust/qemu-api-macros/src/lib.rs b/rust/qemu-api-macros/src/lib.rs
index 1034707..c18bb4e 100644
--- a/rust/qemu-api-macros/src/lib.rs
+++ b/rust/qemu-api-macros/src/lib.rs
@@ -203,8 +203,8 @@ fn derive_tryinto_body(
     Ok(quote! {
         #(const #discriminants: #repr = #name::#discriminants as #repr;)*;
         match value {
-            #(#discriminants => Ok(#name::#discriminants),)*
-            _ => Err(value),
+            #(#discriminants => core::result::Result::Ok(#name::#discriminants),)*
+            _ => core::result::Result::Err(value),
         }
     })
 }
@@ -236,7 +236,8 @@ fn derive_tryinto_or_error(input: DeriveInput) -> Result<proc_macro2::TokenStrea
         impl core::convert::TryFrom<#repr> for #name {
             type Error = #repr;
 
-            fn try_from(value: #repr) -> Result<Self, Self::Error> {
+            #[allow(ambiguous_associated_items)]
+            fn try_from(value: #repr) -> Result<Self, #repr> {
                 #body
             }
         }
diff --git a/rust/qemu-api/Cargo.toml b/rust/qemu-api/Cargo.toml
index c96cf50..db7000d 100644
--- a/rust/qemu-api/Cargo.toml
+++ b/rust/qemu-api/Cargo.toml
@@ -15,7 +15,9 @@ rust-version.workspace = true
 
 [dependencies]
 qemu_api_macros = { path = "../qemu-api-macros" }
+anyhow = "~1.0"
 libc = "0.2.162"
+foreign = "~0.3.1"
 
 [features]
 default = ["debug_cell"]
diff --git a/rust/qemu-api/meson.build b/rust/qemu-api/meson.build
index b532281..cac8595 100644
--- a/rust/qemu-api/meson.build
+++ b/rust/qemu-api/meson.build
@@ -19,6 +19,7 @@ _qemu_api_rs = static_library(
       'src/cell.rs',
       'src/chardev.rs',
       'src/errno.rs',
+      'src/error.rs',
       'src/irq.rs',
       'src/memory.rs',
       'src/module.rs',
@@ -35,7 +36,7 @@ _qemu_api_rs = static_library(
   override_options: ['rust_std=2021', 'build.rust_std=2021'],
   rust_abi: 'rust',
   rust_args: _qemu_api_cfg,
-  dependencies: [libc_rs, qemu_api_macros, qemuutil_rs,
+  dependencies: [anyhow_rs, foreign_rs, libc_rs, qemu_api_macros, qemuutil_rs,
                  qom, hwcore, chardev, migration],
 )
 
diff --git a/rust/qemu-api/src/error.rs b/rust/qemu-api/src/error.rs
new file mode 100644
index 0000000..e114fc4
--- /dev/null
+++ b/rust/qemu-api/src/error.rs
@@ -0,0 +1,416 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+//! Error propagation for QEMU Rust code
+//!
+//! This module contains [`Error`], the bridge between Rust errors and
+//! [`Result`](std::result::Result)s and QEMU's C [`Error`](bindings::Error)
+//! struct.
+//!
+//! For FFI code, [`Error`] provides functions to simplify conversion between
+//! the Rust ([`Result<>`](std::result::Result)) and C (`Error**`) conventions:
+//!
+//! * [`ok_or_propagate`](crate::Error::ok_or_propagate),
+//!   [`bool_or_propagate`](crate::Error::bool_or_propagate),
+//!   [`ptr_or_propagate`](crate::Error::ptr_or_propagate) can be used to build
+//!   a C return value while also propagating an error condition
+//!
+//! * [`err_or_else`](crate::Error::err_or_else) and
+//!   [`err_or_unit`](crate::Error::err_or_unit) can be used to build a `Result`
+//!
+//! This module is most commonly used at the boundary between C and Rust code;
+//! other code will usually access it through the
+//! [`qemu_api::Result`](crate::Result) type alias, and will use the
+//! [`std::error::Error`] interface to let C errors participate in Rust's error
+//! handling functionality.
+//!
+//! Rust code can also create use this module to create an error object that
+//! will be passed up to C code, though in most cases this will be done
+//! transparently through the `?` operator.  Errors can be constructed from a
+//! simple error string, from an [`anyhow::Error`] to pass any other Rust error
+//! type up to C code, or from a combination of the two.
+//!
+//! The third case, corresponding to [`Error::with_error`], is the only one that
+//! requires mentioning [`qemu_api::Error`](crate::Error) explicitly.  Similar
+//! to how QEMU's C code handles errno values, the string and the
+//! `anyhow::Error` object will be concatenated with `:` as the separator.
+
+use std::{
+    borrow::Cow,
+    ffi::{c_char, c_int, c_void, CStr},
+    fmt::{self, Display},
+    panic, ptr,
+};
+
+use foreign::{prelude::*, OwnedPointer};
+
+use crate::bindings;
+
+pub type Result<T> = std::result::Result<T, Error>;
+
+#[derive(Debug)]
+pub struct Error {
+    msg: Option<Cow<'static, str>>,
+    /// Appends the print string of the error to the msg if not None
+    cause: Option<anyhow::Error>,
+    file: &'static str,
+    line: u32,
+}
+
+impl std::error::Error for Error {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        self.cause.as_ref().map(AsRef::as_ref)
+    }
+
+    #[allow(deprecated)]
+    fn description(&self) -> &str {
+        self.msg
+            .as_deref()
+            .or_else(|| self.cause.as_deref().map(std::error::Error::description))
+            .expect("no message nor cause?")
+    }
+}
+
+impl Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let mut prefix = "";
+        if let Some(ref msg) = self.msg {
+            write!(f, "{msg}")?;
+            prefix = ": ";
+        }
+        if let Some(ref cause) = self.cause {
+            write!(f, "{prefix}{cause}")?;
+        } else if prefix.is_empty() {
+            panic!("no message nor cause?");
+        }
+        Ok(())
+    }
+}
+
+impl From<String> for Error {
+    #[track_caller]
+    fn from(msg: String) -> Self {
+        let location = panic::Location::caller();
+        Error {
+            msg: Some(Cow::Owned(msg)),
+            cause: None,
+            file: location.file(),
+            line: location.line(),
+        }
+    }
+}
+
+impl From<&'static str> for Error {
+    #[track_caller]
+    fn from(msg: &'static str) -> Self {
+        let location = panic::Location::caller();
+        Error {
+            msg: Some(Cow::Borrowed(msg)),
+            cause: None,
+            file: location.file(),
+            line: location.line(),
+        }
+    }
+}
+
+impl From<anyhow::Error> for Error {
+    #[track_caller]
+    fn from(error: anyhow::Error) -> Self {
+        let location = panic::Location::caller();
+        Error {
+            msg: None,
+            cause: Some(error),
+            file: location.file(),
+            line: location.line(),
+        }
+    }
+}
+
+impl Error {
+    /// Create a new error, prepending `msg` to the
+    /// description of `cause`
+    #[track_caller]
+    pub fn with_error(msg: impl Into<Cow<'static, str>>, cause: impl Into<anyhow::Error>) -> Self {
+        let location = panic::Location::caller();
+        Error {
+            msg: Some(msg.into()),
+            cause: Some(cause.into()),
+            file: location.file(),
+            line: location.line(),
+        }
+    }
+
+    /// Consume a result, returning `false` if it is an error and
+    /// `true` if it is successful.  The error is propagated into
+    /// `errp` like the C API `error_propagate` would do.
+    ///
+    /// # Safety
+    ///
+    /// `errp` must be a valid argument to `error_propagate`;
+    /// typically it is received from C code and need not be
+    /// checked further at the Rust↔C boundary.
+    pub unsafe fn bool_or_propagate(result: Result<()>, errp: *mut *mut bindings::Error) -> bool {
+        // SAFETY: caller guarantees errp is valid
+        unsafe { Self::ok_or_propagate(result, errp) }.is_some()
+    }
+
+    /// Consume a result, returning a `NULL` pointer if it is an error and
+    /// a C representation of the contents if it is successful.  This is
+    /// similar to the C API `error_propagate`, but it panics if `*errp`
+    /// is not `NULL`.
+    ///
+    /// # Safety
+    ///
+    /// `errp` must be a valid argument to `error_propagate`;
+    /// typically it is received from C code and need not be
+    /// checked further at the Rust↔C boundary.
+    ///
+    /// See [`propagate`](Error::propagate) for more information.
+    #[must_use]
+    pub unsafe fn ptr_or_propagate<T: CloneToForeign>(
+        result: Result<T>,
+        errp: *mut *mut bindings::Error,
+    ) -> *mut T::Foreign {
+        // SAFETY: caller guarantees errp is valid
+        unsafe { Self::ok_or_propagate(result, errp) }.clone_to_foreign_ptr()
+    }
+
+    /// Consume a result in the same way as `self.ok()`, but also propagate
+    /// a possible error into `errp`.  This is similar to the C API
+    /// `error_propagate`, but it panics if `*errp` is not `NULL`.
+    ///
+    /// # Safety
+    ///
+    /// `errp` must be a valid argument to `error_propagate`;
+    /// typically it is received from C code and need not be
+    /// checked further at the Rust↔C boundary.
+    ///
+    /// See [`propagate`](Error::propagate) for more information.
+    pub unsafe fn ok_or_propagate<T>(
+        result: Result<T>,
+        errp: *mut *mut bindings::Error,
+    ) -> Option<T> {
+        result.map_err(|err| unsafe { err.propagate(errp) }).ok()
+    }
+
+    /// Equivalent of the C function `error_propagate`.  Fill `*errp`
+    /// with the information container in `self` if `errp` is not NULL;
+    /// then consume it.
+    ///
+    /// This is similar to the C API `error_propagate`, but it panics if
+    /// `*errp` is not `NULL`.
+    ///
+    /// # Safety
+    ///
+    /// `errp` must be a valid argument to `error_propagate`; it can be
+    /// `NULL` or it can point to any of:
+    /// * `error_abort`
+    /// * `error_fatal`
+    /// * a local variable of (C) type `Error *`
+    ///
+    /// Typically `errp` is received from C code and need not be
+    /// checked further at the Rust↔C boundary.
+    pub unsafe fn propagate(self, errp: *mut *mut bindings::Error) {
+        if errp.is_null() {
+            return;
+        }
+
+        // SAFETY: caller guarantees that errp and *errp are valid
+        unsafe {
+            assert_eq!(*errp, ptr::null_mut());
+            bindings::error_propagate(errp, self.clone_to_foreign_ptr());
+        }
+    }
+
+    /// Convert a C `Error*` into a Rust `Result`, using
+    /// `Ok(())` if `c_error` is NULL.  Free the `Error*`.
+    ///
+    /// # Safety
+    ///
+    /// `c_error` must be `NULL` or valid; typically it was initialized
+    /// with `ptr::null_mut()` and passed by reference to a C function.
+    pub unsafe fn err_or_unit(c_error: *mut bindings::Error) -> Result<()> {
+        // SAFETY: caller guarantees c_error is valid
+        unsafe { Self::err_or_else(c_error, || ()) }
+    }
+
+    /// Convert a C `Error*` into a Rust `Result`, calling `f()` to
+    /// obtain an `Ok` value if `c_error` is NULL.  Free the `Error*`.
+    ///
+    /// # Safety
+    ///
+    /// `c_error` must be `NULL` or point to a valid C [`struct
+    /// Error`](bindings::Error); typically it was initialized with
+    /// `ptr::null_mut()` and passed by reference to a C function.
+    pub unsafe fn err_or_else<T, F: FnOnce() -> T>(
+        c_error: *mut bindings::Error,
+        f: F,
+    ) -> Result<T> {
+        // SAFETY: caller guarantees c_error is valid
+        let err = unsafe { Option::<Self>::from_foreign(c_error) };
+        match err {
+            None => Ok(f()),
+            Some(err) => Err(err),
+        }
+    }
+}
+
+impl FreeForeign for Error {
+    type Foreign = bindings::Error;
+
+    unsafe fn free_foreign(p: *mut bindings::Error) {
+        // SAFETY: caller guarantees p is valid
+        unsafe {
+            bindings::error_free(p);
+        }
+    }
+}
+
+impl CloneToForeign for Error {
+    fn clone_to_foreign(&self) -> OwnedPointer<Self> {
+        // SAFETY: all arguments are controlled by this function
+        unsafe {
+            let err: *mut c_void = libc::malloc(std::mem::size_of::<bindings::Error>());
+            let err: &mut bindings::Error = &mut *err.cast();
+            *err = bindings::Error {
+                msg: format!("{self}").clone_to_foreign_ptr(),
+                err_class: bindings::ERROR_CLASS_GENERIC_ERROR,
+                src_len: self.file.len() as c_int,
+                src: self.file.as_ptr().cast::<c_char>(),
+                line: self.line as c_int,
+                func: ptr::null_mut(),
+                hint: ptr::null_mut(),
+            };
+            OwnedPointer::new(err)
+        }
+    }
+}
+
+impl FromForeign for Error {
+    unsafe fn cloned_from_foreign(c_error: *const bindings::Error) -> Self {
+        // SAFETY: caller guarantees c_error is valid
+        unsafe {
+            let error = &*c_error;
+            let file = if error.src_len < 0 {
+                // NUL-terminated
+                CStr::from_ptr(error.src).to_str()
+            } else {
+                // Can become str::from_utf8 with Rust 1.87.0
+                std::str::from_utf8(std::slice::from_raw_parts(
+                    &*error.src.cast::<u8>(),
+                    error.src_len as usize,
+                ))
+            };
+
+            Error {
+                msg: FromForeign::cloned_from_foreign(error.msg),
+                cause: None,
+                file: file.unwrap(),
+                line: error.line as u32,
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::ffi::CStr;
+
+    use anyhow::anyhow;
+    use foreign::OwnedPointer;
+
+    use super::*;
+    use crate::{assert_match, bindings};
+
+    #[track_caller]
+    fn error_for_test(msg: &CStr) -> OwnedPointer<Error> {
+        // SAFETY: all arguments are controlled by this function
+        let location = panic::Location::caller();
+        unsafe {
+            let err: *mut c_void = libc::malloc(std::mem::size_of::<bindings::Error>());
+            let err: &mut bindings::Error = &mut *err.cast();
+            *err = bindings::Error {
+                msg: msg.clone_to_foreign_ptr(),
+                err_class: bindings::ERROR_CLASS_GENERIC_ERROR,
+                src_len: location.file().len() as c_int,
+                src: location.file().as_ptr().cast::<c_char>(),
+                line: location.line() as c_int,
+                func: ptr::null_mut(),
+                hint: ptr::null_mut(),
+            };
+            OwnedPointer::new(err)
+        }
+    }
+
+    unsafe fn error_get_pretty<'a>(local_err: *mut bindings::Error) -> &'a CStr {
+        unsafe { CStr::from_ptr(bindings::error_get_pretty(local_err)) }
+    }
+
+    #[test]
+    #[allow(deprecated)]
+    fn test_description() {
+        use std::error::Error;
+
+        assert_eq!(super::Error::from("msg").description(), "msg");
+        assert_eq!(super::Error::from("msg".to_owned()).description(), "msg");
+    }
+
+    #[test]
+    fn test_display() {
+        assert_eq!(&*format!("{}", Error::from("msg")), "msg");
+        assert_eq!(&*format!("{}", Error::from("msg".to_owned())), "msg");
+        assert_eq!(&*format!("{}", Error::from(anyhow!("msg"))), "msg");
+
+        assert_eq!(
+            &*format!("{}", Error::with_error("msg", anyhow!("cause"))),
+            "msg: cause"
+        );
+    }
+
+    #[test]
+    fn test_bool_or_propagate() {
+        unsafe {
+            let mut local_err: *mut bindings::Error = ptr::null_mut();
+
+            assert!(Error::bool_or_propagate(Ok(()), &mut local_err));
+            assert_eq!(local_err, ptr::null_mut());
+
+            let my_err = Error::from("msg");
+            assert!(!Error::bool_or_propagate(Err(my_err), &mut local_err));
+            assert_ne!(local_err, ptr::null_mut());
+            assert_eq!(error_get_pretty(local_err), c"msg");
+            bindings::error_free(local_err);
+        }
+    }
+
+    #[test]
+    fn test_ptr_or_propagate() {
+        unsafe {
+            let mut local_err: *mut bindings::Error = ptr::null_mut();
+
+            let ret = Error::ptr_or_propagate(Ok("abc".to_owned()), &mut local_err);
+            assert_eq!(String::from_foreign(ret), "abc");
+            assert_eq!(local_err, ptr::null_mut());
+
+            let my_err = Error::from("msg");
+            assert_eq!(
+                Error::ptr_or_propagate(Err::<String, _>(my_err), &mut local_err),
+                ptr::null_mut()
+            );
+            assert_ne!(local_err, ptr::null_mut());
+            assert_eq!(error_get_pretty(local_err), c"msg");
+            bindings::error_free(local_err);
+        }
+    }
+
+    #[test]
+    fn test_err_or_unit() {
+        unsafe {
+            let result = Error::err_or_unit(ptr::null_mut());
+            assert_match!(result, Ok(()));
+
+            let err = error_for_test(c"msg");
+            let err = Error::err_or_unit(err.into_inner()).unwrap_err();
+            assert_eq!(&*format!("{err}"), "msg");
+        }
+    }
+}
diff --git a/rust/qemu-api/src/lib.rs b/rust/qemu-api/src/lib.rs
index 234a94e..93902fc 100644
--- a/rust/qemu-api/src/lib.rs
+++ b/rust/qemu-api/src/lib.rs
@@ -19,6 +19,7 @@ pub mod callbacks;
 pub mod cell;
 pub mod chardev;
 pub mod errno;
+pub mod error;
 pub mod irq;
 pub mod memory;
 pub mod module;
@@ -34,6 +35,8 @@ use std::{
     ffi::c_void,
 };
 
+pub use error::{Error, Result};
+
 #[cfg(HAVE_GLIB_WITH_ALIGNED_ALLOC)]
 extern "C" {
     fn g_aligned_alloc0(
diff --git a/rust/qemu-api/src/qdev.rs b/rust/qemu-api/src/qdev.rs
index 1279d7a..0610959 100644
--- a/rust/qemu-api/src/qdev.rs
+++ b/rust/qemu-api/src/qdev.rs
@@ -12,10 +12,11 @@ use std::{
 pub use bindings::{ClockEvent, DeviceClass, Property, ResetType};
 
 use crate::{
-    bindings::{self, qdev_init_gpio_in, qdev_init_gpio_out, Error, ResettableClass},
+    bindings::{self, qdev_init_gpio_in, qdev_init_gpio_out, ResettableClass},
     callbacks::FnCall,
     cell::{bql_locked, Opaque},
     chardev::Chardev,
+    error::{Error, Result},
     irq::InterruptSource,
     prelude::*,
     qom::{ObjectClass, ObjectImpl, Owned},
@@ -108,7 +109,7 @@ pub trait DeviceImpl: ObjectImpl + ResettablePhasesImpl + IsA<DeviceState> {
     ///
     /// If not `None`, the parent class's `realize` method is overridden
     /// with the function pointed to by `REALIZE`.
-    const REALIZE: Option<fn(&Self)> = None;
+    const REALIZE: Option<fn(&Self) -> Result<()>> = None;
 
     /// An array providing the properties that the user can set on the
     /// device.  Not a `const` because referencing statics in constants
@@ -134,10 +135,13 @@ pub trait DeviceImpl: ObjectImpl + ResettablePhasesImpl + IsA<DeviceState> {
 /// readable/writeable from one thread at any time.
 unsafe extern "C" fn rust_realize_fn<T: DeviceImpl>(
     dev: *mut bindings::DeviceState,
-    _errp: *mut *mut Error,
+    errp: *mut *mut bindings::Error,
 ) {
     let state = NonNull::new(dev).unwrap().cast::<T>();
-    T::REALIZE.unwrap()(unsafe { state.as_ref() });
+    let result = T::REALIZE.unwrap()(unsafe { state.as_ref() });
+    unsafe {
+        Error::ok_or_propagate(result, errp);
+    }
 }
 
 unsafe impl InterfaceType for ResettableClass {
diff --git a/rust/wrapper.h b/rust/wrapper.h
index beddd9a..6060d3b 100644
--- a/rust/wrapper.h
+++ b/rust/wrapper.h
@@ -60,6 +60,7 @@ typedef enum memory_order {
 #include "hw/qdev-properties-system.h"
 #include "hw/irq.h"
 #include "qapi/error.h"
+#include "qapi/error-internal.h"
 #include "migration/vmstate.h"
 #include "chardev/char-serial.h"
 #include "exec/memattrs.h"