Subject: [PATCH v5 08/17] powerpc/64s: Make flush_and_reload_slb a no-op when radix is enabled

From: Nicholas Piggin <[email-masked]>
Date: Mon, 29 Nov 2021 13:07:54 +1000

The radix test can exclude slb_flush_all_realmode() from being called
because flush_and_reload_slb() is only expected to flush ERAT when
called by flush_erat(), which is only on pre-ISA v3.0 CPUs that do not
support radix.

This helps the later change to make hash support configurable to not
introduce runtime changes to radix mode behaviour.

Signed-off-by: Nicholas Piggin <[email-masked]>
---
 arch/powerpc/kernel/mce_power.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kernel/mce_power.c b/arch/powerpc/kernel/mce_power.c
index c2f55fe7092d..cf5263b648fc 100644
--- a/arch/powerpc/kernel/mce_power.c
+++ b/arch/powerpc/kernel/mce_power.c
@@ -80,12 +80,12 @@ static bool mce_in_guest(void)
 #ifdef CONFIG_PPC_BOOK3S_64
 void flush_and_reload_slb(void)
 {
-	/* Invalidate all SLBs */
-	slb_flush_all_realmode();
-
 	if (early_radix_enabled())
 		return;
 
+	/* Invalidate all SLBs */
+	slb_flush_all_realmode();
+
 	/*
 	 * This probably shouldn't happen, but it may be possible it's
 	 * called in early boot before SLB shadows are allocated.
-- 
2.23.0