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2025-06-06rust/hpet: Drop BqlCell wrapper for num_timersZhao Liu1-16/+11
Now that the num_timers field is initialized as a property, someone may change its default value using qdev_prop_set_uint8(), but the value is fixed after the Rust code sees it first. Since there is no need to modify it after realize(), it is not to be necessary to have a BqlCell wrapper. Signed-off-by: Zhao Liu <zhao1.liu@intel.com> Link: https://lore.kernel.org/r/20250520152750.2542612-4-zhao1.liu@intel.com [Remove .into() as well. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-06rust/hpet: return errors from realize if properties are incorrectPaolo Bonzini2-13/+10
Match the code in hpet.c; this also allows removing the BqlCell from the num_timers field. Reviewed-by: Zhao Liu <zhao1.liu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-06hpet: return errors from realize if properties are incorrectPaolo Bonzini1-7/+8
Do not silently adjust num_timers, and fail if intcap is 0. Reviewed-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Zhao Liu <zhao1.liu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-06hpet: adjust VMState for consistency with Rust versionPaolo Bonzini1-3/+3
No functional change intended. Suggested-by: Zhao Liu <zhao1.liu@intel.com> Reviewed-by: Zhao Liu <zhao1.liu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-06rust/hpet: change type of num_timers to usizePaolo Bonzini1-12/+12
Remove the need to convert after every read of the BqlCell. Because the vmstate uses a u8 as the size of the VARRAY, this requires switching the VARRAY to use num_timers_save; which in turn requires ensuring that the num_timers_save is always there. For simplicity do this by removing support for version 1, which QEMU has not been producing for ~15 years. Reviewed-by: Zhao Liu <zhao1.liu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-06rust: qdev: support returning errors from realizePaolo Bonzini3-8/+14
Reviewed-by: Zhao Liu <zhao1.liu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05rust: qemu-api: add tests for Error bindingsPaolo Bonzini1-0/+104
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05rust: qemu-api: add bindings to ErrorPaolo Bonzini7-0/+341
Provide an implementation of std::error::Error that bridges the Rust anyhow::Error and std::panic::Location types with QEMU's Error*. It also has several utility methods, analogous to error_propagate(), that convert a Result into a return value + Error** pair. One important difference is that these propagation methods *panic* if *errp is NULL, unlike error_propagate() which eats subsequent errors[1]. The reason for this is that in C you have an error_set*() call at the site where the error is created, and calls to error_propagate() are relatively rare. In Rust instead, even though these functions do "propagate" a qemu_api::Error into a C Error**, there is no error_setg() anywhere that could check for non-NULL errp and call abort(). error_propagate()'s behavior of ignoring subsequent errors is generally considered weird, and there would be a bigger risk of triggering it from Rust code. [1] This is actually a violation of the preconditions of error_propagate(), so it should not happen. But you never know... Reviewed-by: Zhao Liu <zhao1.liu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05util/error: make func optionalPaolo Bonzini2-2/+9
The function name is not available in Rust, so make it optional. Reviewed-by: Zhao Liu <zhao1.liu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05util/error: allow non-NUL-terminated err->srcPaolo Bonzini2-3/+11
Rust makes the current file available as a statically-allocated string, but without a NUL terminator. Allow this by storing an optional maximum length in the Error. Reviewed-by: Zhao Liu <zhao1.liu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05util/error: expose Error definition to Rust codePaolo Bonzini3-9/+28
This is used to preserve the file and line in a roundtrip from C Error to Rust and back to C. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05subprojects: add the foreign cratePaolo Bonzini7-3/+41
This is a cleaned up and separated version of the patches at https://lore.kernel.org/all/20240701145853.1394967-4-pbonzini@redhat.com/ https://lore.kernel.org/all/20240701145853.1394967-5-pbonzini@redhat.com/ Its first user will be the Error bindings; for example a QEMU Error ** can be converted to a Rust Option using unsafe { Option::<Error>::from_foreign(c_error) } Reviewed-by: Zhao Liu <zhao1.liu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05subprojects: add the anyhow cratePaolo Bonzini7-3/+46
This is a standard replacement for Box<dyn Error> which is more efficient (it only occcupies one word) and provides a backtrace of the error. This could be plumbed into &error_abort in the future. Reviewed-by: Zhao Liu <zhao1.liu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03rust: qemu-api-macros: add from_bits and into_bits to #[derive(TryInto)]Paolo Bonzini1-8/+36
These const functions make it possible to use enums easily together with the bitfield-struct crate. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03rust: pl011: use the bits macroPaolo Bonzini5-44/+49
This avoids the repeated ".0" when using the Interrupt struct. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03rust: add "bits", a custom bitflags implementationPaolo Bonzini8-0/+728
One common thing that device emulation does is manipulate bitmasks, for example to check whether two bitmaps have common bits. One example in the pl011 crate is the checks for pending interrupts, where an interrupt cause corresponds to at least one interrupt source from a fixed set. Unfortunately, this is one case where Rust *can* provide some kind of abstraction but it does so with a rather Perl-ish There Is More Way To Do It. It is not something where a crate like "bilge" helps, because it only covers the packing of bits in a structure; operations like "are all bits of Y set in X" almost never make sense for bit-packed structs; you need something else, there are several crates that do it and of course we're going to roll our own. In particular I examined three: - bitmask (https://docs.rs/bitmask/0.5.0/bitmask/) does not support const at all. This is a showstopper because one of the ugly things in the current pl011 code is the ugliness of code that defines interrupt masks at compile time: pub const E: Self = Self(Self::OE.0 | Self::BE.0 | Self::PE.0 | Self::FE.0); or even worse: const IRQMASK: [u32; 6] = [ Interrupt::E.0 | Interrupt::MS.0 | Interrupt::RT.0 | Interrupt::TX.0 | Interrupt::RX.0, ... } You would have to use roughly the same code---"bitmask" only helps with defining the struct. - bitmask_enum (https://docs.rs/bitmask-enum/2.2.5/bitmask_enum/) does not have a good separation of "valid" and "invalid" bits, so for example "!x" will invert all 16 bits if you choose u16 as the representation -- even if you only defined 10 bits. This makes it easier to introduce subtle bugs in comparisons. - bitflags (https://docs.rs/bitflags/2.6.0/bitflags/) is generally the most used such crate and is the one that I took most inspiration from with respect to the syntax. It's a pretty sophisticated implementation, with a lot of bells and whistles such as an implementation of "Iter" that returns the bits one at a time. The main thing that all of them lack, however, is a way to simplify the ugly definitions like the above. "bitflags" includes const methods that perform AND/OR/XOR of masks (these are necessary because Rust operator overloading does not support const yet, and therefore overloaded operators cannot be used in the definition of a "static" variable), but they become even more verbose and unmanageable, like Interrupt::E.union(Interrupt::MS).union(Interrupt::RT).union(Interrupt::TX).union(Interrupt::RX) This was the main reason to create "bits", which allows something like bits!(Interrupt: E | MS | RT | TX | RX) and expands it 1) add "Interrupt::" in front of all identifiers 2) convert operators to the wordy const functions like "union". It supports boolean operators "&", "|", "^", "!" and parentheses, with a relatively simple recursive descent parser that's implemented in qemu_api_macros. Since I don't remember exactly how the macro was developed, I cannot exclude that it contains code from "bitflags". Therefore, I am conservatively leaving in the MIT and Apache 2.0 licenses from bitflags. In fact, I think there would be a benefit in being able to push code back to "bitflags" anyway whenever applicable, so that the two libraries do not diverge too much, so that's another reason to use this. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03i386/tdvf: Fix build on 32-bit hostCédric Le Goater1-3/+3
Use PRI formats where required. Cc: Isaku Yamahata <isaku.yamahata@intel.com> Signed-off-by: Cédric Le Goater <clg@redhat.com> Link: https://lore.kernel.org/r/20250602173101.1052983-3-clg@redhat.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03i386/tdx: Fix build on 32-bit hostCédric Le Goater1-13/+13
Use PRI formats where required and fix pointer cast. Cc: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Cédric Le Goater <clg@redhat.com> Link: https://lore.kernel.org/r/20250602173101.1052983-2-clg@redhat.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03meson: use config_base_arch for target librariesPierrick Bouvier1-4/+3
Fixed commit introduced common dependencies for target libraries. Alas, it wrongly reused the 'target' variable, which was previously set from another loop. Thus, some dependencies were missing depending on order of target list, as found here [1]. The fix is to use the correct config_base_arch instead. Kudos to Thomas Huth who had this right, before I reimplement it, and introduce this bug. [1] https://lore.kernel.org/qemu-devel/c54469ce-0385-4aea-b345-47711e9e61de@linaro.org/ Fixes: 4fb54de823e9 (meson: build target libraries with common dependencies) Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Tested-by: Cédric Le Goater <clg@redhat.com> Link: https://lore.kernel.org/r/20250602233801.2699961-1-pierrick.bouvier@linaro.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03target/i386: Add the immediate form MSR access instruction supportXin Li (Intel)2-1/+5
The immediate form of MSR access instructions are primarily motivated by performance, not code size: by having the MSR number in an immediate, it is available *much* earlier in the pipeline, which allows the hardware much more leeway about how a particular MSR is handled. Signed-off-by: Xin Li (Intel) <xin@zytor.com> Link: https://lore.kernel.org/r/20250103084827.1820007-4-xin@zytor.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03target/i386: Add a new CPU feature word for CPUID.7.1.ECXXin Li (Intel)2-1/+23
The immediate form of MSR access instructions will use this new CPU feature word. Signed-off-by: Xin Li (Intel) <xin@zytor.com> Link: https://lore.kernel.org/r/20250103084827.1820007-3-xin@zytor.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03target/i386: Remove FRED dependency on WRMSRNSXin Li (Intel)1-4/+0
WRMSRNS doesn't become a required feature for FERD, and Linux has removed the dependency, as such remove it from Qemu. Cc: qemu-stable@nongnu.org Signed-off-by: Xin Li (Intel) <xin@zytor.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20250103084827.1820007-2-xin@zytor.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03rust: use native Meson support for clippy and rustdocPaolo Bonzini6-22/+10
Meson has support for invoking clippy and rustdoc on all crates (1.7.0 for clippy, 1.8.0 for rustdoc). Use it instead of the homegrown version; this requires disabling the multiple_crate_versions lint (the only one that was enabled from the "cargo" group)---which was not particularly useful anyway because all dependencies are converted by hand into Meson subprojects. rustfmt is still not supported. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03rust: cell: remove support for running doctests with "cargo test --doc"Paolo Bonzini1-13/+9
This is not needed anymore now that tests link with libqemuutil. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03rust: add qemu-api doctests to "meson test"Paolo Bonzini4-9/+16
Doctests are weird. They are essentially integration tests, but they're "ran" by executing rustdoc --test, which takes a compiler-ish command line. This is supported by Meson 1.8.0. Because they run the linker and need all the .o files, run them in the build jobs rather than the test jobs. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03build, dockerfiles: add support for detecting rustdocPaolo Bonzini5-0/+16
rustdoc is effectively a custom version of rustc, and it is necessary to specify it in order to run doctests from Meson. Add the relevant configure option and environment variables. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03rust: use "objects" for Rust executables as wellPaolo Bonzini3-24/+7
libqemuutil is not meant be linked as a whole; if modules are enabled, doing so results in undefined symbols (corresponding to QMP commands) in rust/qemu-api/rust-qemu-api-integration. Support for "objects" in Rust executables is available in Meson 1.8.0; use it to switching to the same dependencies that C targets use: link_with for libqemuutil, and objects for everything else. Reported-by: Bernhard Beschow <shentey@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03meson: update to version 1.8.1Paolo Bonzini6-4/+16
This adds several improvements to Rust support, including native clippy and rustdoc targets, the "objects" keyword, and running doctests. Require it only when Rust support is requested, to avoid putting a strict requirement on all build platforms for the sake of an experimental feature. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03rust: bindings: allow ptr_offset_with_castPaolo Bonzini1-0/+1
This is produced by recent versions of bindgen: warning: use of `offset` with a `usize` casted to an `isize` --> /builds/bonzini/qemu/rust/target/debug/build/qemu_api-35cb647f4db404b8/out/bindings.inc.rs:39:21 | 39 | let byte = *(core::ptr::addr_of!((*this).storage) as *const u8).offset(byte_index as isize); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `(core::ptr::addr_of!((*this).storage) as *const u8).add(byte_index)` | = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_offset_with_cast = note: `#[warn(clippy::ptr_offset_with_cast)]` on by default warning: use of `offset` with a `usize` casted to an `isize` --> /builds/bonzini/qemu/rust/target/debug/build/qemu_api-35cb647f4db404b8/out/bindings.inc.rs:68:13 | 68 | (core::ptr::addr_of_mut!((*this).storage) as *mut u8).offset(byte_index as isize); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `(core::ptr::addr_of_mut!((*this).storage) as *mut u8).add(byte_index)` | = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_offset_with_cast This seems to be new in bindgen 0.71.0, possibly related to bindgen commit 33006185b7878 ("Add raw_ref_macros feature", 2024-11-22). Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03qapi: Improve documentation around job state @concludedMarkus Armbruster2-13/+8
We use "the query list" in a few places. It's not entirely obvious what that means. It's actually the output of query-jobs or query-block-jobs. Documentation of @auto-dismiss talks about the job disappearing from the query list when it reaches state @concluded. This is less than precise. The job doesn't merely disappear from the query list, it disappears, period. Documentation of JobStatus @concluded explains "the job will remain in the query list until it is dismissed". Again less than precise. It remains in state @concluded until dismissed. Rephrase without use of "the query list" for clarity and precision. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-14-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Tidy up references to job state CONCLUDEDMarkus Armbruster2-6/+6
When talking about the job state machine, we refer to the states like READY, ABORTING, CONCLUDED, and so forth. Except in two places, where we use JOB_STATUS_CONCLUDED. Replace by CONCLUDED for consistency. We should arguably use the JobStatus enum values instead. Left for another day. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-13-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Mention both job-cancel and block-job-cancel in doc commentsMarkus Armbruster1-5/+5
Several doc comments mention block-job-cancel where the more generic job-cancel would also work. Adjust them to mention both. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-12-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Refer to job-FOO instead of deprecated block-job-FOO in docsMarkus Armbruster1-29/+28
We deprecated several block-job-FOO commands in commit b836bf2ab68 (qapi/block-core: deprecate some block-job- APIs). Update the doc comments to refer to their replacements instead. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-11-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Spell JSON null correctly in blockdev-reopen documentationMarkus Armbruster1-1/+1
The doc comment misspells JSON null as NULL. Fix that. Cc: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-10-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Use proper markup instead of CAPS for emphasis in doc commentsMarkus Armbruster4-19/+19
Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-9-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Fix capitalization in doc commentsMarkus Armbruster8-10/+10
Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-8-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Correct spelling of QEMU in doc commentsMarkus Armbruster10-26/+26
Improve awkward phrasing in migrate-incoming While there. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-7-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Drop a problematic (Since: 2.11) from query-hotpluggable-cpusMarkus Armbruster1-1/+1
There is a (Since: 2.11) in a query-hotpluggable-cpus example. Versioning information ought to be in the command description, not examples. The command description is basically empty (there is a TODO about it). What exactly didn't work before 2.11 is not quite clear from the documentation. The example was added in commit 4dc3b151882 (s390x: implement query-hotpluggable-cpus), which suggests the command failed for the s390x target until then. This was almost eight years ago, and I doubt anyone still cares about this detail. Simply delete the problematic (Since: 2.11). Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-6-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Avoid breaking lines within (since X.Y)Markus Armbruster8-66/+66
Easier on the eyes and for grep. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-5-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Move (since X.Y) to end of descriptionMarkus Armbruster2-12/+12
By convention, we put (since X.Y) at the end of the description. Move the ones that somehow ended up in the middle of the description to the end. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-4-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Tidy up whitespace in doc commentsMarkus Armbruster8-24/+25
Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-3-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-03qapi: Tidy up run-together sentences in doc commentsMarkus Armbruster5-28/+28
Fixes: a937b6aa739f (qapi: Reformat doc comments to conform to current conventions) Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-ID: <20250527073916.1243024-2-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2025-06-02trace/simple: seperate hot paths of tracing fucntionsTanish Desai1-13/+10
This change improves performance by moving the hot path of the trace_vhost_commit()(or any other trace function) logic to the header file. Previously, even when the trace event was disabled, the function call chain:- trace_vhost_commit()(Or any other trace function) → _nocheck__trace_vhost_commit() → _simple_trace_vhost_commit() incurred a significant function prologue overhead before checking the trace state. Disassembly of _simple_trace_vhost_commit() (from the .c file) showed that 11 out of the first 14 instructions were prologue-related, including: 0x10 stp x29, x30, [sp, #-64]! Prologue: allocates 64-byte frame and saves old FP (x29) & LR (x30) 0x14 adrp x3, trace_events_enabled_count Prologue: computes page-base of the trace-enable counter 0x18 adrp x2, __stack_chk_guard Important (maybe prolog don't know?)(stack-protector): starts up the stack-canary load 0x1c mov x29, sp Prologue: sets new frame pointer 0x20 ldr x3, [x3] Prologue: loads the actual trace-enabled count 0x24 stp x19, x20, [sp, #16] Prologue: spills callee-saved regs used by this function (x19, x20) 0x28 and w20, w0, #0xff Tracepoint setup: extracts the low-8 bits of arg0 as the “event boolean” 0x2c ldr x2, [x2] Prologue (cont’d): completes loading of the stack-canary value 0x30 and w19, w1, #0xff Tracepoint setup: extracts low-8 bits of arg1 0x34 ldr w0, [x3] Important: loads the current trace-enabled flag from memory 0x38 ldr x1, [x2] Prologue (cont’d): reads the canary 0x3c str x1, [sp, #56] Prologue (cont’d): writes the canary into the new frame 0x40 mov x1, #0 Prologue (cont’d): zeroes out x1 for the upcoming branch test 0x44 cbnz w0, 0x88 Important: if tracing is disabled (w0==0) skip the heavy path entirely The trace-enabled check happens after the prologue. This is wasteful when tracing is disabled, which is often the case in production. To optimize this: _nocheck__trace_vhost_commit() is now fully inlined in the .h file with the hot path.It checks trace_event_get_state() before calling into _simple_trace_vhost_commit(), which remains in .c. This avoids calling into the .c function altogether when the tracepoint is disabled, thereby skipping unnecessary prologue instructions. This results in better performance by removing redundant instructions in the tracing fast path. Signed-off-by: Tanish Desai <tanishdesai37@gmail.com> Message-id: 20250528192528.3968-1-tanishdesai37@gmail.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2025-06-02hw/i386/pc_piix: Fix RTC ISA IRQ wiring of isapc machineBernhard Beschow1-0/+5
Commit 56b1f50e3c10 ("hw/i386/pc: Wire RTC ISA IRQs in south bridges") attempted to refactor RTC IRQ wiring which was previously done in pc_basic_device_init() but forgot about the isapc machine. Fix this by wiring in the code section dedicated exclusively to the isapc machine. Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2961 Fixes: 56b1f50e3c10 ("hw/i386/pc: Wire RTC ISA IRQs in south bridges") cc: qemu-stable Signed-off-by: Bernhard Beschow <shentey@gmail.com> Reviewed-by: Mark Cave-Ayland <mark.caveayland@nutanix.com> Message-Id: <20250526203820.1853-1-shentey@gmail.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-06-02vdpa: move memory listener register to vhost_vdpa_initEugenio Pérez1-7/+28
Current memory operations like pinning may take a lot of time at the destination. Currently they are done after the source of the migration is stopped, and before the workload is resumed at the destination. This is a period where neigher traffic can flow, nor the VM workload can continue (downtime). We can do better as we know the memory layout of the guest RAM at the destination from the moment that all devices are initializaed. So moving that operation allows QEMU to communicate the kernel the maps while the workload is still running in the source, so Linux can start mapping them. As a small drawback, there is a time in the initialization where QEMU cannot respond to QMP etc. By some testing, this time is about 0.2seconds. This may be further reduced (or increased) depending on the vdpa driver and the platform hardware, and it is dominated by the cost of memory pinning. This matches the time that we move out of the called downtime window. The downtime is measured as the elapsed trace time between the last vhost_vdpa_suspend on the source and the last vhost_vdpa_set_vring_enable_one on the destination. In other words, from "guest CPUs freeze" to the instant the final Rx/Tx queue-pair is able to start moving data. Using ConnectX-6 Dx (MLX5) NICs in vhost-vDPA mode with 8 queue-pairs, the series reduces guest-visible downtime during back-to-back live migrations by more than half: - 39G VM: 4.72s -> 2.09s (-2.63s, ~56% improvement) - 128G VM: 14.72s -> 5.83s (-8.89s, ~60% improvement) Tested-by: Lei Yang <leiyang@redhat.com> Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com> Message-Id: <20250522145839.59974-8-jonah.palmer@oracle.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-06-02vdpa: move iova_tree allocation to net_vhost_vdpa_initEugenio Pérez2-34/+18
As we are moving to keep the mapping through all the vdpa device life instead of resetting it at VirtIO reset, we need to move all its dependencies to the initialization too. In particular devices with x-svq=on need a valid iova_tree from the beginning. Simplify the code also consolidating the two creation points: the first data vq in case of SVQ active and CVQ start in case only CVQ uses it. Tested-by: Lei Yang <leiyang@redhat.com> Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com> Acked-by: Jason Wang <jasowang@redhat.com> Suggested-by: Si-Wei Liu <si-wei.liu@oracle.com> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com> Message-Id: <20250522145839.59974-7-jonah.palmer@oracle.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-06-02vdpa: reorder listener assignmentEugenio Pérez1-1/+1
Since commit f6fe3e333f ("vdpa: move memory listener to vhost_vdpa_shared") this piece of code repeatedly assign shared->listener members. This was not a problem as it was not used until device start. However next patches move the listener registration to this vhost_vdpa_init function. When the listener is registered it is added to an embedded linked list, so setting its members again will cause memory corruption to the linked list node. Do the right thing and only set it in the first vdpa device. Tested-by: Lei Yang <leiyang@redhat.com> Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com> Message-Id: <20250522145839.59974-6-jonah.palmer@oracle.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-06-02vdpa: add listener_registeredEugenio Pérez2-1/+12
Check if the listener has been registered or not, so it needs to be registered again at start. Tested-by: Lei Yang <leiyang@redhat.com> Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com> Message-Id: <20250522145839.59974-5-jonah.palmer@oracle.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-06-02vdpa: set backend capabilities at vhost_vdpa_initEugenio Pérez1-1/+6
The backend does not reset them until the vdpa file descriptor is closed so there is no harm in doing it only once. This allows the destination of a live migration to premap memory in batches, using VHOST_BACKEND_F_IOTLB_BATCH. Tested-by: Lei Yang <leiyang@redhat.com> Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com> Message-Id: <20250522145839.59974-4-jonah.palmer@oracle.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-06-02vdpa: reorder vhost_vdpa_set_backend_capEugenio Pérez1-30/+30
It will be used directly by vhost_vdpa_init. Tested-by: Lei Yang <leiyang@redhat.com> Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com> Message-Id: <20250522145839.59974-3-jonah.palmer@oracle.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>