From bc276ecba132caccb1fda5863a652c15def2b8c6 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin 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@vger.kernel.org # v4.11+ Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/mce_power.c | 7 +++++++ arch/powerpc/mm/hash_native_64.c | 4 ++-- 2 files changed, 9 insertions(+), 2 deletions(-) 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,