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From:   Thomas Gleixner <tglx@linutronix.de>
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Subject: [patch V2 17/38] x86/xen/hvm: Get rid of DEAD_FROZEN handling
References: <20230504185733.126511787@linutronix.de>
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Date:   Thu,  4 May 2023 21:02:25 +0200 (CEST)
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From: Thomas Gleixner <tglx@linutronix.de>

No point in this conditional voodoo. Un-initializing the lock mechanism is
safe to be called unconditionally even if it was already invoked when the
CPU died.

Remove the invocation of xen_smp_intr_free() as that has been already
cleaned up in xen_cpu_dead_hvm().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: xen-devel@lists.xenproject.org

---
 arch/x86/xen/enlighten_hvm.c |   11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)
---
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c
@@ -161,13 +161,12 @@ static int xen_cpu_up_prepare_hvm(unsign
 	int rc = 0;
 
 	/*
-	 * This can happen if CPU was offlined earlier and
-	 * offlining timed out in common_cpu_die().
+	 * If a CPU was offlined earlier and offlining timed out then the
+	 * lock mechanism is still initialized. Uninit it unconditionally
+	 * as it's safe to call even if already uninited. Interrupts and
+	 * timer have already been handled in xen_cpu_dead_hvm().
 	 */
-	if (cpu_report_state(cpu) == CPU_DEAD_FROZEN) {
-		xen_smp_intr_free(cpu);
-		xen_uninit_lock_cpu(cpu);
-	}
+	xen_uninit_lock_cpu(cpu);
 
 	if (cpu_acpi_id(cpu) != U32_MAX)
 		per_cpu(xen_vcpu_id, cpu) = cpu_acpi_id(cpu);