From 1e300d053cb59a7ef932dc2e55aa372ea786519e Mon Sep 17 00:00:00 2001
From: Like Xu <like.xu@linux.intel.com>
Date: Mon, 29 Jul 2019 20:35:49 +0800
Subject: [PATCH] KVM: x86/vPMU: refine kvm_pmu err msg when event creation
failed
commit 6fc3977ccc5d3c22e851f2dce2d3ce2a0a843842 upstream.
If a perf_event creation fails due to any reason of the host perf
subsystem, it has no chance to log the corresponding event for guest
which may cause abnormal sampling data in guest result. In debug mode,
this message helps to understand the state of vPMC and we may not
limit the number of occurrences but not in a spamming style.
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
---
arch/x86/kvm/pmu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index 952aebd0a8a3..acc8d217f656 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -131,8 +131,8 @@ static void pmc_reprogram_counter(struct kvm_pmc *pmc, u32 type,
intr ? kvm_perf_overflow_intr :
kvm_perf_overflow, pmc);
if (IS_ERR(event)) {
- printk_once("kvm_pmu: event creation failed %ld\n",
- PTR_ERR(event));
+ pr_debug_ratelimited("kvm_pmu: event creation failed %ld for pmc->idx = %d\n",
+ PTR_ERR(event), pmc->idx);
return;
}
--
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