[PATCH v2 15/19] spapr: Fix machine reset deadlock from replay-record

[Nicholas Piggin <npiggin@gmail.com>]

When the machine is reset to load a new snapshot while being debugged
with replay-record, it is done from another thread, so the CPU does
not run the register setting operations. Set CPU registers directly in
machine reset.

Cc: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 hw/ppc/spapr.c         | 20 ++++++++++++++++++--
 include/hw/ppc/spapr.h |  1 +
 target/ppc/compat.c    | 19 +++++++++++++++++++
 target/ppc/cpu.h       |  1 +
 4 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 1c8b8d57a7..7d84244f03 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1322,6 +1322,22 @@ void spapr_set_all_lpcrs(target_ulong value, target_ulong mask)
     }
 }
 
+/* May be used when the machine is not running */
+void spapr_init_all_lpcrs(target_ulong value, target_ulong mask)
+{
+    CPUState *cs;
+    CPU_FOREACH(cs) {
+        PowerPCCPU *cpu = POWERPC_CPU(cs);
+        CPUPPCState *env = &cpu->env;
+        target_ulong lpcr;
+
+        lpcr = env->spr[SPR_LPCR];
+        lpcr &= ~(LPCR_HR | LPCR_UPRT);
+        ppc_store_lpcr(cpu, lpcr);
+    }
+}
+
+
 static bool spapr_get_pate(PPCVirtualHypervisor *vhyp, PowerPCCPU *cpu,
                            target_ulong lpid, ppc_v3_pate_t *entry)
 {
@@ -1583,7 +1599,7 @@ int spapr_reallocate_hpt(SpaprMachineState *spapr, int shift, Error **errp)
     }
     /* We're setting up a hash table, so that means we're not radix */
     spapr->patb_entry = 0;
-    spapr_set_all_lpcrs(0, LPCR_HR | LPCR_UPRT);
+    spapr_init_all_lpcrs(0, LPCR_HR | LPCR_UPRT);
     return 0;
 }
 
@@ -1661,7 +1677,7 @@ static void spapr_machine_reset(MachineState *machine, ShutdownCause reason)
     spapr_ovec_cleanup(spapr->ov5_cas);
     spapr->ov5_cas = spapr_ovec_new();
 
-    ppc_set_compat_all(spapr->max_compat_pvr, &error_fatal);
+    ppc_init_compat_all(spapr->max_compat_pvr, &error_fatal);
 
     /*
      * This is fixing some of the default configuration of the XIVE
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index 538b2dfb89..f47e8419a5 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -1012,6 +1012,7 @@ bool spapr_check_pagesize(SpaprMachineState *spapr, hwaddr pagesize,
 #define SPAPR_OV5_XIVE_BOTH     0x80 /* Only to advertise on the platform */
 
 void spapr_set_all_lpcrs(target_ulong value, target_ulong mask);
+void spapr_init_all_lpcrs(target_ulong value, target_ulong mask);
 hwaddr spapr_get_rtas_addr(void);
 bool spapr_memory_hot_unplug_supported(SpaprMachineState *spapr);
 
diff --git a/target/ppc/compat.c b/target/ppc/compat.c
index 7949a24f5a..ebef2cccec 100644
--- a/target/ppc/compat.c
+++ b/target/ppc/compat.c
@@ -229,6 +229,25 @@ int ppc_set_compat_all(uint32_t compat_pvr, Error **errp)
     return 0;
 }
 
+/* To be used when the machine is not running */
+int ppc_init_compat_all(uint32_t compat_pvr, Error **errp)
+{
+    CPUState *cs;
+
+    CPU_FOREACH(cs) {
+        PowerPCCPU *cpu = POWERPC_CPU(cs);
+        int ret;
+
+        ret = ppc_set_compat(cpu, compat_pvr, errp);
+
+        if (ret < 0) {
+            return ret;
+        }
+    }
+
+    return 0;
+}
+
 int ppc_compat_max_vthreads(PowerPCCPU *cpu)
 {
     const CompatInfo *compat = compat_by_pvr(cpu->compat_pvr);
diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index 9e491e05eb..f8fe0db5cd 100644
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -1504,6 +1504,7 @@ int ppc_set_compat(PowerPCCPU *cpu, uint32_t compat_pvr, Error **errp);
 
 #if !defined(CONFIG_USER_ONLY)
 int ppc_set_compat_all(uint32_t compat_pvr, Error **errp);
+int ppc_init_compat_all(uint32_t compat_pvr, Error **errp);
 #endif
 int ppc_compat_max_vthreads(PowerPCCPU *cpu);
 void ppc_compat_add_property(Object *obj, const char *name,
-- 
2.40.1