[Qemu-devel] [PATCH v4] spapr: quantify error messages regarding capability settings

[Daniel Black <daniel@linux.ibm.com>]

Its not immediately obvious how cap-X=Y setting need to be applied
to the command line so, for spapr capability error messages, this
has been clarified to:

 appending -machine cap-X=Y

The wrong value messages have been left as is, as the user has found
the right location.

Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Daniel Black <daniel@linux.ibm.com>
---
v4 Message inline rather than macro. greppability nitpick accepted with
grace and the magic of %s/CAPABILITY_HINT("\([^"]*\)")/" try appending -machine \1"/g.
v3 Hint, and not all messages, (can't use error_append_hint on
error_fatal) from Greg Kurz
v2 Improved error message thanks David Gibson

Left the "appending" as its not obvious more that one -machine
arguement is allowed.

 hw/ppc/spapr_caps.c | 42 ++++++++++++++++++++++++++++--------------
 1 file changed, 28 insertions(+), 14 deletions(-)

diff --git a/hw/ppc/spapr_caps.c b/hw/ppc/spapr_caps.c
index bbb001f84a..405286db6f 100644
--- a/hw/ppc/spapr_caps.c
+++ b/hw/ppc/spapr_caps.c
@@ -194,10 +194,12 @@ static void cap_htm_apply(SpaprMachineState *spapr, uint8_t val, Error **errp)
     }
     if (tcg_enabled()) {
         error_setg(errp,
-                   "No Transactional Memory support in TCG, try cap-htm=off");
+                   "No Transactional Memory support in TCG,"
+                   " try appending -machine cap-htm=off");
     } else if (kvm_enabled() && !kvmppc_has_cap_htm()) {
         error_setg(errp,
-"KVM implementation does not support Transactional Memory, try cap-htm=off"
+"KVM implementation does not support Transactional Memory,"
+                   " try appending -machine cap-htm=off"
             );
     }
 }
@@ -215,7 +217,8 @@ static void cap_vsx_apply(SpaprMachineState *spapr, uint8_t val, Error **errp)
      * rid of anything that doesn't do VMX */
     g_assert(env->insns_flags & PPC_ALTIVEC);
     if (!(env->insns_flags2 & PPC2_VSX)) {
-        error_setg(errp, "VSX support not available, try cap-vsx=off");
+        error_setg(errp, "VSX support not available,"
+                   " try appending -machine cap-vsx=off");
     }
 }
 
@@ -229,7 +232,8 @@ static void cap_dfp_apply(SpaprMachineState *spapr, uint8_t val, Error **errp)
         return;
     }
     if (!(env->insns_flags2 & PPC2_DFP)) {
-        error_setg(errp, "DFP support not available, try cap-dfp=off");
+        error_setg(errp, "DFP support not available,"
+                   " try appending -machine cap-dfp=off");
     }
 }
 
@@ -253,7 +257,8 @@ static void cap_safe_cache_apply(SpaprMachineState *spapr, uint8_t val,
                    cap_cfpc_possible.vals[val]);
     } else if (kvm_enabled() && (val > kvm_val)) {
         error_setg(errp,
-"Requested safe cache capability level not supported by kvm, try cap-cfpc=%s",
+                   "Requested safe cache capability level not supported by kvm,"
+                   " try appending -machine cap-cfpc=%s",
                    cap_cfpc_possible.vals[kvm_val]);
     }
 
@@ -281,7 +286,8 @@ static void cap_safe_bounds_check_apply(SpaprMachineState *spapr, uint8_t val,
                    cap_sbbc_possible.vals[val]);
     } else if (kvm_enabled() && (val > kvm_val)) {
         error_setg(errp,
-"Requested safe bounds check capability level not supported by kvm, try cap-sbbc=%s",
+"Requested safe bounds check capability level not supported by kvm,"
+                   " try appending -machine cap-sbbc=%s",
                    cap_sbbc_possible.vals[kvm_val]);
     }
 
@@ -312,7 +318,8 @@ static void cap_safe_indirect_branch_apply(SpaprMachineState *spapr,
                    cap_ibs_possible.vals[val]);
     } else if (kvm_enabled() && (val > kvm_val)) {
         error_setg(errp,
-"Requested safe indirect branch capability level not supported by kvm, try cap-ibs=%s",
+"Requested safe indirect branch capability level not supported by kvm,"
+                   " try appending -machine cap-ibs=%s",
                    cap_ibs_possible.vals[kvm_val]);
     }
 
@@ -401,11 +408,13 @@ static void cap_nested_kvm_hv_apply(SpaprMachineState *spapr,
 
     if (tcg_enabled()) {
         error_setg(errp,
-                   "No Nested KVM-HV support in tcg, try cap-nested-hv=off");
+                   "No Nested KVM-HV support in tcg,"
+                   " try appending -machine cap-nested-hv=off");
     } else if (kvm_enabled()) {
         if (!kvmppc_has_cap_nested_kvm_hv()) {
             error_setg(errp,
-"KVM implementation does not support Nested KVM-HV, try cap-nested-hv=off");
+"KVM implementation does not support Nested KVM-HV,"
+                       " try appending -machine cap-nested-hv=off");
         } else if (kvmppc_set_cap_nested_kvm_hv(val) < 0) {
                 error_setg(errp,
 "Error enabling cap-nested-hv with KVM, try cap-nested-hv=off");
@@ -435,10 +444,12 @@ static void cap_large_decr_apply(SpaprMachineState *spapr,
 
         if (!kvm_nr_bits) {
             error_setg(errp,
-                       "No large decrementer support, try cap-large-decr=off");
+                       "No large decrementer support,"
+                        " try appending -machine cap-large-decr=off");
         } else if (pcc->lrg_decr_bits != kvm_nr_bits) {
             error_setg(errp,
-"KVM large decrementer size (%d) differs to model (%d), try -cap-large-decr=off",
+"KVM large decrementer size (%d) differs to model (%d),"
+                " try appending -machine cap-large-decr=off",
                 kvm_nr_bits, pcc->lrg_decr_bits);
         }
     }
@@ -454,7 +465,8 @@ static void cap_large_decr_cpu_apply(SpaprMachineState *spapr,
     if (kvm_enabled()) {
         if (kvmppc_enable_cap_large_decr(cpu, val)) {
             error_setg(errp,
-                       "No large decrementer support, try cap-large-decr=off");
+                       "No large decrementer support,"
+                       " try appending -machine cap-large-decr=off");
         }
     }
 
@@ -474,10 +486,12 @@ static void cap_ccf_assist_apply(SpaprMachineState *spapr, uint8_t val,
     if (tcg_enabled() && val) {
         /* TODO - for now only allow broken for TCG */
         error_setg(errp,
-"Requested count cache flush assist capability level not supported by tcg, try cap-ccf-assist=off");
+"Requested count cache flush assist capability level not supported by tcg,"
+                   " try appending -machine cap-ccf-assist=off");
     } else if (kvm_enabled() && (val > kvm_val)) {
         error_setg(errp,
-"Requested count cache flush assist capability level not supported by kvm, try cap-ccf-assist=off");
+"Requested count cache flush assist capability level not supported by kvm,"
+                   " try appending -machine cap-ccf-assist=off");
     }
 }
 
-- 
2.21.0