[PATCH 4/5] x86/sev-es: Correctly track IRQ states in runtime #VC handler

[Joerg Roedel]

From: Joerg Roedel <jroedel@xxxxxxx>

Call irqentry_nmi_enter()/irqentry_nmi_exit() in the #VC handler to
correctly track the IRQ state during its execution.

Reported-by: Andy Lutomirski <luto@xxxxxxxxxx>
Fixes: 0786138c78e79 ("x86/sev-es: Add a Runtime #VC Exception Handler")
Cc: stable@xxxxxxxxxxxxxxx # v5.10+
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
 arch/x86/kernel/sev-es.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index e1eeb3ef58c5..3d8ec5bf6f79 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -1270,13 +1270,12 @@ static __always_inline bool on_vc_fallback_stack(struct pt_regs *regs)
 DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication)
 {
 	struct sev_es_runtime_data *data = this_cpu_read(runtime_data);
+	irqentry_state_t irq_state;
 	struct ghcb_state state;
 	struct es_em_ctxt ctxt;
 	enum es_result result;
 	struct ghcb *ghcb;
 
-	lockdep_assert_irqs_disabled();
-
 	/*
 	 * Handle #DB before calling into !noinstr code to avoid recursive #DB.
 	 */
@@ -1285,6 +1284,8 @@ DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication)
 		return;
 	}
 
+	irq_state = irqentry_nmi_enter(regs);
+	lockdep_assert_irqs_disabled();
 	instrumentation_begin();
 
 	/*
@@ -1347,6 +1348,7 @@ DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication)
 
 out:
 	instrumentation_end();
+	irqentry_nmi_exit(regs, irq_state);
 
 	return;
 
-- 
2.30.1