From cd1149eef30af3dff5f07d838cd465cc26afbf6f Mon Sep 17 00:00:00 2001 From: Bin Lu Date: Tue, 23 Jun 2020 23:35:10 -0400 Subject: supporting sError injection step 2 on Arm64 I disabled DAIF(DEBUG, sError, IRQ, FIQ) in guest kernel mode, and enabled them in guest user mode. So, I can make sure all DAIF-s come from guest user mode, and then the case 'TestBounceStress' can passed on Arm64. Test steps: 1, cd pkg/sentry/platform/kvm 2, bazel test kvm_test --strip=never --test_output=streamed Signed-off-by: Bin Lu --- pkg/sentry/platform/kvm/bluepill_arm64.go | 4 +-- pkg/sentry/platform/kvm/bluepill_arm64_unsafe.go | 2 +- pkg/sentry/platform/kvm/machine_arm64_unsafe.go | 6 ---- pkg/sentry/platform/ring0/aarch64.go | 35 ++++++++++++------------ pkg/sentry/platform/ring0/entry_arm64.s | 8 ------ pkg/sentry/platform/ring0/kernel_arm64.go | 2 +- 6 files changed, 22 insertions(+), 35 deletions(-) diff --git a/pkg/sentry/platform/kvm/bluepill_arm64.go b/pkg/sentry/platform/kvm/bluepill_arm64.go index dba563160..ed5ae03d3 100644 --- a/pkg/sentry/platform/kvm/bluepill_arm64.go +++ b/pkg/sentry/platform/kvm/bluepill_arm64.go @@ -49,7 +49,7 @@ func bluepillArchEnter(context *arch.SignalContext64) (c *vCPU) { regs.Sp = context.Sp regs.Pc = context.Pc regs.Pstate = context.Pstate - regs.Pstate &^= uint64(ring0.KernelFlagsClear) + regs.Pstate &^= uint64(ring0.PsrFlagsClear) regs.Pstate |= ring0.KernelFlagsSet return } @@ -63,7 +63,7 @@ func bluepillArchExit(c *vCPU, context *arch.SignalContext64) { context.Sp = regs.Sp context.Pc = regs.Pc context.Pstate = regs.Pstate - context.Pstate &^= uint64(ring0.UserFlagsClear) + context.Pstate &^= uint64(ring0.PsrFlagsClear) context.Pstate |= ring0.UserFlagsSet lazyVfp := c.GetLazyVFP() diff --git a/pkg/sentry/platform/kvm/bluepill_arm64_unsafe.go b/pkg/sentry/platform/kvm/bluepill_arm64_unsafe.go index 8b64f3a1e..b35c930e2 100644 --- a/pkg/sentry/platform/kvm/bluepill_arm64_unsafe.go +++ b/pkg/sentry/platform/kvm/bluepill_arm64_unsafe.go @@ -41,7 +41,7 @@ func fpsimdPtr(addr *byte) *arch.FpsimdContext { func dieArchSetup(c *vCPU, context *arch.SignalContext64, guestRegs *userRegs) { // If the vCPU is in user mode, we set the stack to the stored stack // value in the vCPU itself. We don't want to unwind the user stack. - if guestRegs.Regs.Pstate&ring0.PSR_MODE_MASK == ring0.PSR_MODE_EL0t { + if guestRegs.Regs.Pstate&ring0.PsrModeMask == ring0.UserFlagsSet { regs := c.CPU.Registers() context.Regs[0] = regs.Regs[0] context.Sp = regs.Sp diff --git a/pkg/sentry/platform/kvm/machine_arm64_unsafe.go b/pkg/sentry/platform/kvm/machine_arm64_unsafe.go index ff8c068c0..307a7645f 100644 --- a/pkg/sentry/platform/kvm/machine_arm64_unsafe.go +++ b/pkg/sentry/platform/kvm/machine_arm64_unsafe.go @@ -151,12 +151,6 @@ func (c *vCPU) initArchState() error { // the MMIO address base. arm64HypercallMMIOBase = toLocation - data = ring0.PsrDefaultSet | ring0.KernelFlagsSet - reg.id = _KVM_ARM64_REGS_PSTATE - if err := c.setOneRegister(®); err != nil { - return err - } - // Initialize the PCID database. if hasGuestPCID { // Note that NewPCIDs may return a nil table here, in which diff --git a/pkg/sentry/platform/ring0/aarch64.go b/pkg/sentry/platform/ring0/aarch64.go index 8122ac6e2..87a573cc4 100644 --- a/pkg/sentry/platform/ring0/aarch64.go +++ b/pkg/sentry/platform/ring0/aarch64.go @@ -26,30 +26,31 @@ const ( _PMD_PGT_SIZE = 0x4000 _PTE_PGT_BASE = 0x7000 _PTE_PGT_SIZE = 0x1000 - - _PSR_D_BIT = 0x00000200 - _PSR_A_BIT = 0x00000100 - _PSR_I_BIT = 0x00000080 - _PSR_F_BIT = 0x00000040 ) const ( - // PSR bits - PSR_MODE_EL0t = 0x00000000 - PSR_MODE_EL1t = 0x00000004 - PSR_MODE_EL1h = 0x00000005 - PSR_MODE_MASK = 0x0000000f + // DAIF bits:debug, sError, IRQ, FIQ. + _PSR_D_BIT = 0x00000200 + _PSR_A_BIT = 0x00000100 + _PSR_I_BIT = 0x00000080 + _PSR_F_BIT = 0x00000040 + _PSR_DAIF_SHIFT = 6 + _PSR_DAIF_MASK = 0xf << _PSR_DAIF_SHIFT - // KernelFlagsSet should always be set in the kernel. - KernelFlagsSet = PSR_MODE_EL1h + // PSR bits. + _PSR_MODE_EL0t = 0x00000000 + _PSR_MODE_EL1t = 0x00000004 + _PSR_MODE_EL1h = 0x00000005 + _PSR_MODE_MASK = 0x0000000f - // UserFlagsSet are always set in userspace. - UserFlagsSet = PSR_MODE_EL0t + PsrFlagsClear = _PSR_MODE_MASK | _PSR_DAIF_MASK + PsrModeMask = _PSR_MODE_MASK - KernelFlagsClear = PSR_MODE_MASK - UserFlagsClear = PSR_MODE_MASK + // KernelFlagsSet should always be set in the kernel. + KernelFlagsSet = _PSR_MODE_EL1h | _PSR_D_BIT | _PSR_A_BIT | _PSR_I_BIT | _PSR_F_BIT - PsrDefaultSet = _PSR_D_BIT | _PSR_A_BIT | _PSR_I_BIT | _PSR_F_BIT + // UserFlagsSet are always set in userspace. + UserFlagsSet = _PSR_MODE_EL0t ) // Vector is an exception vector. diff --git a/pkg/sentry/platform/ring0/entry_arm64.s b/pkg/sentry/platform/ring0/entry_arm64.s index 9fd02d628..d8a7bc2f9 100644 --- a/pkg/sentry/platform/ring0/entry_arm64.s +++ b/pkg/sentry/platform/ring0/entry_arm64.s @@ -312,12 +312,6 @@ ISB $15; \ DSB $15; -#define IRQ_ENABLE \ - MSR $2, DAIFSet; - -#define IRQ_DISABLE \ - MSR $2, DAIFClr; - #define VFP_ENABLE \ MOVD $FPEN_ENABLE, R0; \ WORD $0xd5181040; \ //MSR R0, CPACR_EL1 @@ -509,8 +503,6 @@ TEXT ·kernelExitToEl1(SB),NOSPLIT,$0 // Start is the CPU entrypoint. TEXT ·Start(SB),NOSPLIT,$0 - IRQ_DISABLE - // Init. MOVD $SCTLR_EL1_DEFAULT, R1 MSR R1, SCTLR_EL1 diff --git a/pkg/sentry/platform/ring0/kernel_arm64.go b/pkg/sentry/platform/ring0/kernel_arm64.go index fca3a5478..5b98659b2 100644 --- a/pkg/sentry/platform/ring0/kernel_arm64.go +++ b/pkg/sentry/platform/ring0/kernel_arm64.go @@ -56,7 +56,7 @@ func (c *CPU) SwitchToUser(switchOpts SwitchOpts) (vector Vector) { // Sanitize registers. regs := switchOpts.Registers - regs.Pstate &= ^uint64(UserFlagsClear) + regs.Pstate &= ^uint64(PsrFlagsClear) regs.Pstate |= UserFlagsSet SetTLS(regs.TPIDR_EL0) -- cgit v1.2.3