From c0b27c517acf8a2b359dd373a7e7e88b01a8308e Mon Sep 17 00:00:00 2001
From: Nicholas Piggin <npiggin@gmail.com>
Date: Thu, 26 Nov 2020 20:25:28 +1000
Subject: [PATCH] powerpc/64s/pseries: Fix hash tlbiel_all_isa300 for guest
kernels
References: bsc#1179888 ltc#190253
Patch-mainline: v5.10-rc7
Git-commit: c0b27c517acf8a2b359dd373a7e7e88b01a8308e
tlbiel_all() can not be usable in !HVMODE when running hash presently,
remove HV privileged flushes when running in guest to make it usable.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201126102530.691335-3-npiggin@gmail.com
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/mm/hash_native_64.c | 21 ++++++++++++++-------
1 file changed, 14 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/mm/hash_native_64.c b/arch/powerpc/mm/hash_native_64.c
--- a/arch/powerpc/mm/hash_native_64.c
+++ b/arch/powerpc/mm/hash_native_64.c
@@ -92,16 +92,15 @@ static void tlbiel_all_isa300(unsigned int num_sets, unsigned int is)
asm volatile("ptesync": : :"memory");
/*
- * Flush the first set of the TLB, and any caching of partition table
- * entries. Then flush the remaining sets of the TLB. Hash mode uses
- * partition scoped TLB translations.
+ * Flush the partition table cache if this is HV mode.
*/
- tlbiel_hash_set_isa300(0, is, 0, 2, 0);
- for (set = 1; set < num_sets; set++)
- tlbiel_hash_set_isa300(set, is, 0, 0, 0);
+ if (early_cpu_has_feature(CPU_FTR_HVMODE))
+ tlbiel_hash_set_isa300(0, is, 0, 2, 0);
/*
- * Now invalidate the process table cache.
+ * Now invalidate the process table cache. UPRT=0 HPT modes (what
+ * current hardware implements) do not use the process table, but
+ * add the flushes anyway.
*
* From ISA v3.0B p. 1078:
* The following forms are invalid.
@@ -110,6 +109,14 @@ static void tlbiel_all_isa300(unsigned int num_sets, unsigned int is)
*/
tlbiel_hash_set_isa300(0, is, 0, 2, 1);
+ /*
+ * Then flush the sets of the TLB proper. Hash mode uses
+ * partition scoped TLB translations, which may be flushed
+ * in !HV mode.
+ */
+ for (set = 0; set < num_sets; set++)
+ tlbiel_hash_set_isa300(set, is, 0, 0, 0);
+
asm volatile("ptesync": : :"memory");
asm volatile(PPC_ISA_3_0_INVALIDATE_ERAT "; isync" : : :"memory");
--
2.26.2