SailBugfix: Modifies only mie in write Sie when the interrupt is dele…

…gated

Before modifying each specific interrupt enable bit (e.g., SEIE, STIE, or SSIE), the code checks whether the corresponding bit in Mideleg is set. Mideleg determines whether a specific interrupt is delegated to the supervisor level, so this ensures that only interrupts managed by the supervisor are updated.

src/virt/csr.rs

@@ -541,10 +541,9 @@ impl HwRegisterContextSetter<Csr> for VirtContext {
                 );
             }
             Csr::Sie => {
-                // Clear S bits
-                let mie = self.get(Csr::Mie) & !mie::SIE_FILTER;
-                // Set S bits to new value
-                self.set_csr(Csr::Mie, mie | (value & mie::SIE_FILTER), mctx);
+                // Only delegated interrupts can be enabled through `sie`
+                let mideleg = self.get(Csr::Mideleg);
+                self.csr.mie = (self.csr.mie & !mideleg) | (mideleg & value);
             }
             Csr::Stvec => {
                 match value & 0b11 {