[tip: smp/core] x86/xen/hvm: Get rid of DEAD_FROZEN handling

[tip-bot2 for Thomas Gleixner]

The following commit has been merged into the smp/core branch of tip:

Commit-ID:     ab24eb9abb9c60c45119370731735b79ed79f36c
Gitweb:        https://git.kernel.org/tip/ab24eb9abb9c60c45119370731735b79ed79f36c
Author:        Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate:    Fri, 12 May 2023 23:07:25 +02:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Mon, 15 May 2023 13:44:55 +02:00

x86/xen/hvm: Get rid of DEAD_FROZEN handling

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@xxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Tested-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Tested-by: Oleksandr Natalenko <oleksandr@xxxxxxxxxxxxxx>
Tested-by: Helge Deller <deller@xxxxxx> # parisc
Tested-by: Guilherme G. Piccoli <gpiccoli@xxxxxxxxxx> # Steam Deck
Link: https://lore.kernel.org/r/20230512205256.423407127@xxxxxxxxxxxxx
---
 arch/x86/xen/enlighten_hvm.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
index c1cd28e..a6820ca 100644
--- 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(unsigned int cpu)
 	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);