[Qemu-devel] [PATCH 09/12] target/ppc: Flush the TLB locally when the LPIDR is written

["Cédric Le Goater" <clg@kaod.org>]

From: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Our TCG TLB only tags whether it's a HV vs a guest access, so it must
be flushed when the LPIDR is changed.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 target/ppc/helper.h             |  1 +
 target/ppc/misc_helper.c        | 15 +++++++++++++++
 target/ppc/translate_init.inc.c |  7 ++++++-
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/target/ppc/helper.h b/target/ppc/helper.h
index c7de04e06896..fe293937c646 100644
--- a/target/ppc/helper.h
+++ b/target/ppc/helper.h
@@ -718,6 +718,7 @@ DEF_HELPER_2(store_ptcr, void, env, tl)
 #endif
 DEF_HELPER_2(store_sdr1, void, env, tl)
 DEF_HELPER_2(store_pidr, void, env, tl)
+DEF_HELPER_2(store_lpidr, void, env, tl)
 DEF_HELPER_FLAGS_2(store_tbl, TCG_CALL_NO_RWG, void, env, tl)
 DEF_HELPER_FLAGS_2(store_tbu, TCG_CALL_NO_RWG, void, env, tl)
 DEF_HELPER_FLAGS_2(store_atbl, TCG_CALL_NO_RWG, void, env, tl)
diff --git a/target/ppc/misc_helper.c b/target/ppc/misc_helper.c
index b88493009609..c65d1ade15c2 100644
--- a/target/ppc/misc_helper.c
+++ b/target/ppc/misc_helper.c
@@ -117,6 +117,21 @@ void helper_store_pidr(CPUPPCState *env, target_ulong val)
     tlb_flush(CPU(cpu));
 }
 
+void helper_store_lpidr(CPUPPCState *env, target_ulong val)
+{
+    PowerPCCPU *cpu = ppc_env_get_cpu(env);
+
+    env->spr[SPR_LPIDR] = val;
+
+    /*
+     * We need to flush the TLB on LPID changes as we only tag HV vs
+     * guest in TCG TLB. Also the quadrants means the HV will
+     * potentially access and cache entries for the current LPID as
+     * well.
+     */
+    tlb_flush(CPU(cpu));
+}
+
 void helper_store_hid0_601(CPUPPCState *env, target_ulong val)
 {
     target_ulong hid0;
diff --git a/target/ppc/translate_init.inc.c b/target/ppc/translate_init.inc.c
index 59e0b8676236..6f8b459e3b39 100644
--- a/target/ppc/translate_init.inc.c
+++ b/target/ppc/translate_init.inc.c
@@ -407,6 +407,11 @@ static void spr_write_pidr(DisasContext *ctx, int sprn, int gprn)
     gen_helper_store_pidr(cpu_env, cpu_gpr[gprn]);
 }
 
+static void spr_write_lpidr(DisasContext *ctx, int sprn, int gprn)
+{
+    gen_helper_store_lpidr(cpu_env, cpu_gpr[gprn]);
+}
+
 static void spr_read_hior(DisasContext *ctx, int gprn, int sprn)
 {
     tcg_gen_ld_tl(cpu_gpr[gprn], cpu_env, offsetof(CPUPPCState, excp_prefix));
@@ -7876,7 +7881,7 @@ static void gen_spr_book3s_ids(CPUPPCState *env)
     spr_register_hv(env, SPR_LPIDR, "LPIDR",
                  SPR_NOACCESS, SPR_NOACCESS,
                  SPR_NOACCESS, SPR_NOACCESS,
-                 &spr_read_generic, &spr_write_generic,
+                 &spr_read_generic, &spr_write_lpidr,
                  0x00000000);
     spr_register_hv(env, SPR_HFSCR, "HFSCR",
                  SPR_NOACCESS, SPR_NOACCESS,
-- 
2.20.1