Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "Bugfixes, mostly for ARM and AMD, and more documentation.

  Slightly bigger than usual because I couldn't send out what was
  pending for rc4, but there is nothing worrisome going on. I have more
  fixes pending for guest debugging support (gdbstub) but I will send
  them next week"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (22 commits)
  KVM: X86: Declare KVM_CAP_SET_GUEST_DEBUG properly
  KVM: selftests: Fix build for evmcs.h
  kvm: x86: Use KVM CPU capabilities to determine CR4 reserved bits
  KVM: VMX: Explicitly clear RFLAGS.CF and RFLAGS.ZF in VM-Exit RSB path
  docs/virt/kvm: Document configuring and running nested guests
  KVM: s390: Remove false WARN_ON_ONCE for the PQAP instruction
  kvm: ioapic: Restrict lazy EOI update to edge-triggered interrupts
  KVM: x86: Fixes posted interrupt check for IRQs delivery modes
  KVM: SVM: fill in kvm_run->debug.arch.dr[67]
  KVM: nVMX: Replace a BUG_ON(1) with BUG() to squash clang warning
  KVM: arm64: Fix 32bit PC wrap-around
  KVM: arm64: vgic-v4: Initialize GICv4.1 even in the absence of a virtual ITS
  KVM: arm64: Save/restore sp_el0 as part of __guest_enter
  KVM: arm64: Delete duplicated label in invalid_vector
  KVM: arm64: vgic-its: Fix memory leak on the error path of vgic_add_lpi()
  KVM: arm64: vgic-v3: Retire all pending LPIs on vcpu destroy
  KVM: arm: vgic-v2: Only use the virtual state when userspace accesses pending bits
  KVM: arm: vgic: Only use the virtual state when userspace accesses enable bits
  KVM: arm: vgic: Synchronize the whole guest on GIC{D,R}_I{S,C}ACTIVER read
  KVM: arm64: PSCI: Forbid 64bit functions for 32bit guests
  ...

1 files changed, 23 insertions, 0 deletions

diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S
index d22d0534dd60..90186cf6473e 100644
--- a/arch/arm64/kvm/hyp/entry.S
+++ b/arch/arm64/kvm/hyp/entry.S
@@ -18,6 +18,7 @@
 
 #define CPU_GP_REG_OFFSET(x)	(CPU_GP_REGS + x)
 #define CPU_XREG_OFFSET(x)	CPU_GP_REG_OFFSET(CPU_USER_PT_REGS + 8*x)
+#define CPU_SP_EL0_OFFSET	(CPU_XREG_OFFSET(30) + 8)
 
 	.text
 	.pushsection	.hyp.text, "ax"
@@ -47,6 +48,16 @@
 	ldp	x29, lr,  [\ctxt, #CPU_XREG_OFFSET(29)]
 .endm
 
+.macro save_sp_el0 ctxt, tmp
+	mrs	\tmp,	sp_el0
+	str	\tmp,	[\ctxt, #CPU_SP_EL0_OFFSET]
+.endm
+
+.macro restore_sp_el0 ctxt, tmp
+	ldr	\tmp,	  [\ctxt, #CPU_SP_EL0_OFFSET]
+	msr	sp_el0, \tmp
+.endm
+
 /*
  * u64 __guest_enter(struct kvm_vcpu *vcpu,
  *		     struct kvm_cpu_context *host_ctxt);
@@ -60,6 +71,9 @@ SYM_FUNC_START(__guest_enter)
 	// Store the host regs
 	save_callee_saved_regs x1
 
+	// Save the host's sp_el0
+	save_sp_el0	x1, x2
+
 	// Now the host state is stored if we have a pending RAS SError it must
 	// affect the host. If any asynchronous exception is pending we defer
 	// the guest entry. The DSB isn't necessary before v8.2 as any SError
@@ -83,6 +97,9 @@ alternative_else_nop_endif
 	// when this feature is enabled for kernel code.
 	ptrauth_switch_to_guest x29, x0, x1, x2
 
+	// Restore the guest's sp_el0
+	restore_sp_el0 x29, x0
+
 	// Restore guest regs x0-x17
 	ldp	x0, x1,   [x29, #CPU_XREG_OFFSET(0)]
 	ldp	x2, x3,   [x29, #CPU_XREG_OFFSET(2)]
@@ -130,6 +147,9 @@ SYM_INNER_LABEL(__guest_exit, SYM_L_GLOBAL)
 	// Store the guest regs x18-x29, lr
 	save_callee_saved_regs x1
 
+	// Store the guest's sp_el0
+	save_sp_el0	x1, x2
+
 	get_host_ctxt	x2, x3
 
 	// Macro ptrauth_switch_to_guest format:
@@ -139,6 +159,9 @@ SYM_INNER_LABEL(__guest_exit, SYM_L_GLOBAL)
 	// when this feature is enabled for kernel code.
 	ptrauth_switch_to_host x1, x2, x3, x4, x5
 
+	// Restore the hosts's sp_el0
+	restore_sp_el0 x2, x3
+
 	// Now restore the host regs
 	restore_callee_saved_regs x2