diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/fmt.rs | 3 | ||||
| -rw-r--r-- | src/kvm_sys.rs | 73 | ||||
| -rw-r--r-- | src/vcpu.rs | 66 | ||||
| -rw-r--r-- | src/x86_64.rs | 5 |
4 files changed, 145 insertions, 2 deletions
@@ -12,7 +12,7 @@ impl fmt::Display for kvm_regs { r8 : {:#018x} r9 : {:#018x} r10: {:#018x} r11: {:#018x}\n\ r12: {:#018x} r13: {:#018x} r14: {:#018x} r15: {:#018x}\n\ rsp: {:#018x} rbp: {:#018x}\n\ - rip: {:#018x} rfl: {:#018x} O({}) D({}) I({}) S({}) Z({}) P({}) C({})", + rip: {:#018x} rfl: {:#018x} O({}) D({}) I({}) T({}) S({}) Z({}) P({}) C({})", self.rax, self.rbx, self.rcx, @@ -34,6 +34,7 @@ impl fmt::Display for kvm_regs { rflags_of(self.rflags), rflags_df(self.rflags), rflags_if(self.rflags), + rflags_tf(self.rflags), rflags_sf(self.rflags), rflags_zf(self.rflags), rflags_pf(self.rflags), diff --git a/src/kvm_sys.rs b/src/kvm_sys.rs index d21da47..2ee97a1 100644 --- a/src/kvm_sys.rs +++ b/src/kvm_sys.rs @@ -91,6 +91,32 @@ pub(crate) struct kvm_userspace_memory_region { pub userspace_addr: u64, } +#[cfg(target_arch = "x86_64")] +#[repr(C)] +#[derive(Default, Debug)] +pub struct kvm_debugregs { + pub db: [u64; 4], + pub dr6: u64, + pub dr7: u64, + pub flags: u64, + pub reserved: [u64; 9], +} + +#[repr(C)] +#[derive(Default, Debug)] +pub(crate) struct kvm_guest_debug { + pub control: u32, + pad: u32, + pub arch: kvm_guest_debug_arch, +} + +#[cfg(target_arch = "x86_64")] +#[repr(C)] +#[derive(Default, Debug)] +pub(crate) struct kvm_guest_debug_arch { + pub debugreg: [u64; 8], +} + #[repr(C)] pub(crate) struct kvm_run { request_interrupt_window: u8, @@ -127,11 +153,23 @@ pub(crate) struct kvm_run_mmio { pub is_write: u8, } +#[cfg(target_arch = "x86_64")] +#[repr(C)] +#[derive(Copy, Clone, Debug)] +pub(crate) struct kvm_run_debug { + pub exception: u32, + pad: u32, + pub pc: u64, + pub dr6: u64, + pub dr7: u64, +} + // Only add the union fields used here. #[repr(C)] pub(crate) union kvm_run_union { pub io: kvm_run_io, pub mmio: kvm_run_mmio, + pub debug: kvm_run_debug, padding: [u8; 256], } @@ -194,4 +232,39 @@ mod tests { assert_eq!(mem::size_of::<kvm_run_mmio>(), TEST_KVM_RUN_MMIO_SIZE); assert_eq!(mem::size_of::<kvm_run_union_s>(), TEST_KVM_RUN_UNION_S_SIZE); } + + #[cfg(target_arch = "x86_64")] + #[test] + fn check_kvm_run_x86() { + assert_eq!(mem::size_of::<kvm_run_debug>(), TEST_KVM_RUN_DEBUG_SIZE); + } + + #[cfg(target_arch = "x86_64")] + #[test] + fn check_kvm_debugregs() { + assert_eq!(mem::size_of::<kvm_debugregs>(), TEST_KVM_DEBUGREGS_SIZE); + assert_eq!(mem::align_of::<kvm_debugregs>(), TEST_KVM_DEBUGREGS_ALIGN); + } + + #[test] + fn check_kvm_guest_dbg() { + assert_eq!(mem::size_of::<kvm_guest_debug>(), TEST_KVM_GUEST_DEBUG_SIZE); + assert_eq!( + mem::align_of::<kvm_guest_debug>(), + TEST_KVM_GUEST_DEBUG_ALIGN + ); + } + + #[cfg(target_arch = "x86_64")] + #[test] + fn check_kvm_guest_dbg_arch() { + assert_eq!( + mem::size_of::<kvm_guest_debug_arch>(), + TEST_KVM_GUEST_DEBUG_ARCH_SIZE + ); + assert_eq!( + mem::align_of::<kvm_guest_debug_arch>(), + TEST_KVM_GUEST_DEBUG_ARCH_ALIGN + ); + } } diff --git a/src/vcpu.rs b/src/vcpu.rs index f0d311e..4b25736 100644 --- a/src/vcpu.rs +++ b/src/vcpu.rs @@ -18,6 +18,7 @@ pub enum KvmExit<'cpu> { IoOut(u16, &'cpu [u8]), MmioRead(u64, &'cpu mut [u8]), MmioWrite(u64, &'cpu [u8]), + Debug(u64), } /// Wrapper for VCPU ioctls. @@ -86,6 +87,65 @@ impl Vcpu { .map(|_| ()) } + /// Get the debug registers with the [`KVM_GET_DEBUGREGS`][kvm-get-debugregs] ioctl in form of + /// [`kvm_debugregs`](crate::kvm_sys::kvm_debugregs). + /// + /// [kvm-get-debugregs]: + /// https://www.kernel.org/doc/html/latest/virt/kvm/api.html#kvm-get-debugregs + #[cfg(target_arch = "x86_64")] + pub fn get_debugregs(&self) -> io::Result<kvm_sys::kvm_debugregs> { + let mut dregs = kvm_sys::kvm_debugregs::default(); + ioctl( + &self.vcpu, + kvm_sys::KVM_GET_DEBUGREGS, + &mut dregs as *mut _ as u64, + )?; + Ok(dregs) + } + + /// Set the debug registers with the [`KVM_SET_DEBUGREGS`][kvm-set-debugregs] ioctl in form of + /// [`kvm_debugregs`](crate::kvm_sys::kvm_debugregs). + /// + /// [kvm-set-debugregs]: + /// https://www.kernel.org/doc/html/latest/virt/kvm/api.html#kvm-set-debugregs + #[cfg(target_arch = "x86_64")] + pub fn set_debugregs(&self, dregs: kvm_sys::kvm_debugregs) -> io::Result<()> { + ioctl( + &self.vcpu, + kvm_sys::KVM_SET_DEBUGREGS, + &dregs as *const _ as u64, + ) + .map(|_| ()) + } + + /// Enable or disable guest single steppig (debug) with the + /// [`KVM_GUESTDBG_ENABLE`][kvm-guest-debug] ioctl. + /// + /// [kvm-guest-debug]: https://www.kernel.org/doc/html/latest/virt/kvm/api.html#kvm-set-guest-debug + #[cfg(target_arch = "x86_64")] + pub fn set_single_step(&self, enable: bool) -> io::Result<()> { + let mut dbg = kvm_sys::kvm_guest_debug::default(); + + if enable { + // Enable guest debugging and single stepping. + dbg.control = kvm_sys::KVM_GUESTDBG_ENABLE | kvm_sys::KVM_GUESTDBG_SINGLESTEP; + } + + // Initialize debug registers based on current VCPUs debug register values. + let dregs = self.get_debugregs()?; + dbg.arch.debugreg[0..4].copy_from_slice(&dregs.db); + // DR4-DR5 are reserved. + dbg.arch.debugreg[6] = dregs.dr6; + dbg.arch.debugreg[7] = dregs.dr7; + + ioctl( + &self.vcpu, + kvm_sys::KVM_SET_GUEST_DEBUG, + &dbg as *const _ as u64, + ) + .map(|_| ()) + } + /// Run the guest VCPU with the [`KVM_RUN`][kvm-run] ioctl until it exits with one of the exit /// reasons described in [`KvmExit`](crate::vcpu::KvmExit). /// @@ -128,6 +188,12 @@ impl Vcpu { _ => unreachable!(), } } + kvm_sys::KVM_EXIT_DEBUG => { + // Safe to use union `debug` field, as Kernel instructed us to. + let debug = unsafe { kvm_run.inner.debug }; + + Ok(KvmExit::Debug(debug.pc)) + } r @ _ => { todo!("KVM_EXIT_... (exit_reason={}) not implemented!", r) } diff --git a/src/x86_64.rs b/src/x86_64.rs index ac153e9..d87319c 100644 --- a/src/x86_64.rs +++ b/src/x86_64.rs @@ -16,6 +16,8 @@ mod x86_64 { pub const RFLAGS_ZF: u64 = 1 << 6; /// Sign flag. pub const RFLAGS_SF: u64 = 1 << 7; + /// Trap flag. + pub const RFLAGS_TF: u64 = 1 << 8; /// Sign flag. pub const RFLAGS_IF: u64 = 1 << 9; /// Direction flag. @@ -32,6 +34,7 @@ mod x86_64 { pub const fn rflags_af(r: u64) -> u64 { (r & RFLAGS_AF) >> 4 } pub const fn rflags_zf(r: u64) -> u64 { (r & RFLAGS_ZF) >> 6 } pub const fn rflags_sf(r: u64) -> u64 { (r & RFLAGS_SF) >> 7 } + pub const fn rflags_tf(r: u64) -> u64 { (r & RFLAGS_TF) >> 8 } pub const fn rflags_if(r: u64) -> u64 { (r & RFLAGS_IF) >> 9 } pub const fn rflags_df(r: u64) -> u64 { (r & RFLAGS_DF) >> 10 } pub const fn rflags_of(r: u64) -> u64 { (r & RFLAGS_OF) >> 11 } @@ -155,5 +158,5 @@ mod x86_64 { /// Page region read/write. /// /// If set, region reference by paging entry is writeable. - pub const PAGE_RENTRY_RW: u64 = 1 << 1; + pub const PAGE_ENTRY_RW: u64 = 1 << 1; } |