commit <249fad734a25> ""powerpc/perf: Disable trace_imc pmu"
disables IMC(In-Memory Collection) trace-mode in kernel, since frequent
mode switching between accumulation mode and trace mode via the spr LDBAR
in the hardware can trigger a checkstop(system crash).

Patch to re-enable imc-trace mode in kernel.

The previous patch(1/2) in this series will address the mode switching issue
by implementing a global lock, and will restrict the usage of
accumulation and trace-mode at a time.

Signed-off-by: Anju T Sudhakar <a...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/opal-imc.c | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/opal-imc.c 
b/arch/powerpc/platforms/powernv/opal-imc.c
index 968b9a4d1cd9..7824cc364bc4 100644
--- a/arch/powerpc/platforms/powernv/opal-imc.c
+++ b/arch/powerpc/platforms/powernv/opal-imc.c
@@ -268,14 +268,7 @@ static int opal_imc_counters_probe(struct platform_device 
*pdev)
                        domain = IMC_DOMAIN_THREAD;
                        break;
                case IMC_TYPE_TRACE:
-                       /*
-                        * FIXME. Using trace_imc events to monitor application
-                        * or KVM thread performance can cause a checkstop
-                        * (system crash).
-                        * Disable it for now.
-                        */
-                       pr_info_once("IMC: disabling trace_imc PMU\n");
-                       domain = -1;
+                       domain = IMC_DOMAIN_TRACE;
                        break;
                default:
                        pr_warn("IMC Unknown Device type \n");
-- 
2.20.1

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