The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From bc276ecba132caccb1fda5863a652c15def2b8c6 Mon Sep 17 00:00:00 2001
From: Nicholas Piggin <npiggin@xxxxxxxxx>
Date: Mon, 27 Aug 2018 13:03:01 +1000
Subject: [PATCH] powerpc/64s/hash: Do not use PPC_INVALIDATE_ERAT on CPUs
before POWER9
PPC_INVALIDATE_ERAT is slbia IH=7 which is a new variant introduced
with POWER9, and the result is undefined on earlier CPUs.
Commits 7b9f71f974 ("powerpc/64s: POWER9 machine check handler") and
d4748276ae ("powerpc/64s: Improve local TLB flush for boot and MCE on
POWER9") caused POWER7/8 code to use this instruction. Remove it. An
ERAT flush can be made by invalidatig the SLB, but before POWER9 that
requires a flush and rebolt.
Fixes: 7b9f71f974 ("powerpc/64s: POWER9 machine check handler")
Fixes: d4748276ae ("powerpc/64s: Improve local TLB flush for boot and MCE on POWER9")
Cc: stable@xxxxxxxxxxxxxxx # v4.11+
Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
diff --git a/arch/powerpc/kernel/mce_power.c b/arch/powerpc/kernel/mce_power.c
index 2016b58d564f..6b800eec31f2 100644
--- a/arch/powerpc/kernel/mce_power.c
+++ b/arch/powerpc/kernel/mce_power.c
@@ -89,6 +89,13 @@ void flush_and_reload_slb(void)
static void flush_erat(void)
{
+#ifdef CONFIG_PPC_BOOK3S_64
+ if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) {
+ flush_and_reload_slb();
+ return;
+ }
+#endif
+ /* PPC_INVALIDATE_ERAT can only be used on ISA v3 and newer */
asm volatile(PPC_INVALIDATE_ERAT : : :"memory");
}
diff --git a/arch/powerpc/mm/hash_native_64.c b/arch/powerpc/mm/hash_native_64.c
index 729f02df8290..aaa28fd918fe 100644
--- a/arch/powerpc/mm/hash_native_64.c
+++ b/arch/powerpc/mm/hash_native_64.c
@@ -115,6 +115,8 @@ static void tlbiel_all_isa300(unsigned int num_sets, unsigned int is)
tlbiel_hash_set_isa300(0, is, 0, 2, 1);
asm volatile("ptesync": : :"memory");
+
+ asm volatile(PPC_INVALIDATE_ERAT "; isync" : : :"memory");
}
void hash__tlbiel_all(unsigned int action)
@@ -140,8 +142,6 @@ void hash__tlbiel_all(unsigned int action)
tlbiel_all_isa206(POWER7_TLB_SETS, is);
else
WARN(1, "%s called on pre-POWER7 CPU\n", __func__);
-
- asm volatile(PPC_INVALIDATE_ERAT "; isync" : : :"memory");
}
static inline unsigned long ___tlbie(unsigned long vpn, int psize,
