vmm: Remove "amx" feature gate

Given the AMX x86 feature has been made available since kernel v5.17,
and given we don't have any test validating this feature, there's no
need to keep it behing a Rust feature gate.

Fixes #3996

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

.github/workflows/build.yaml

@@ -42,9 +42,6 @@ jobs:
       - name: Build (default features + tdx)
         run: cargo rustc --locked --bin cloud-hypervisor --features "tdx" -- -D warnings
 
-      - name: Build (default features + amx)
-        run: cargo rustc --locked --bin cloud-hypervisor --features "amx" -- -D warnings
-
       - name: Build (default features + gdb)
         run: cargo rustc --locked --bin cloud-hypervisor --features "gdb" -- -D warnings
 

.github/workflows/quality.yaml

@@ -49,9 +49,6 @@ jobs:
       - name: Clippy (default features)
         run: cargo clippy --locked --all --all-targets --tests -- -D warnings
 
-      - name: Clippy (default features + amx)
-        run: cargo clippy --locked --all --all-targets --tests --features "amx" -- -D warnings
-
       - name: Clippy (default features + gdb)
         run: cargo clippy --locked --all --all-targets --tests --features "gdb" -- -D warnings
 

Cargo.toml

@@ -56,7 +56,6 @@ wait-timeout = "0.2.0"
 default = ["common", "kvm"]
 # Common features for all hypervisors
 common = ["fwdebug"]
-amx = ["vmm/amx"]
 cmos = ["vmm/cmos"]
 fwdebug = ["vmm/fwdebug"]
 gdb = ["vmm/gdb"]

vmm/Cargo.toml

@@ -6,7 +6,6 @@ edition = "2021"
 
 [features]
 default = []
-amx = []
 cmos = ["devices/cmos"]
 fwdebug = ["devices/fwdebug"]
 gdb = ["kvm", "gdbstub", "gdbstub_arch"]

vmm/src/config.rs

@@ -472,7 +472,7 @@ pub struct CpuAffinity {
 
 #[derive(Clone, Debug, Default, PartialEq, Eq, Deserialize, Serialize)]
 pub struct CpuFeatures {
-    #[cfg(all(feature = "amx", target_arch = "x86_64"))]
+    #[cfg(target_arch = "x86_64")]
     #[serde(default)]
     pub amx: bool,
 }
@@ -593,7 +593,7 @@ impl CpusConfig {
         let mut features = CpuFeatures::default();
         for s in features_list.0 {
             match <std::string::String as AsRef<str>>::as_ref(&s) {
-                #[cfg(all(feature = "amx", target_arch = "x86_64"))]
+                #[cfg(target_arch = "x86_64")]
                 "amx" => {
                     features.amx = true;
                     Ok(())

vmm/src/cpu.rs

@@ -161,7 +161,7 @@ pub enum Error {
     #[error("Error translating virtual address: {0}")]
     TranslateVirtualAddress(#[source] anyhow::Error),
 
-    #[cfg(all(feature = "amx", target_arch = "x86_64"))]
+    #[cfg(target_arch = "x86_64")]
     #[error("Error setting up AMX: {0}")]
     AmxEnable(#[source] anyhow::Error),
 }
@@ -636,7 +636,7 @@ impl CpuManager {
             )
             .map_err(Error::CommonCpuId)?
         };
-        #[cfg(all(feature = "amx", target_arch = "x86_64"))]
+        #[cfg(target_arch = "x86_64")]
         if config.features.amx {
             const ARCH_GET_XCOMP_GUEST_PERM: usize = 0x1024;
             const ARCH_REQ_XCOMP_GUEST_PERM: usize = 0x1025;