From 0ba6502ce167fc3d598c08c2cc3b4ed7ca5aa251 Mon Sep 17 00:00:00 2001 From: Dapeng Mi Date: Tue, 28 Oct 2025 14:42:14 +0800 Subject: [PATCH] perf/x86/intel: Fix KASAN global-out-of-bounds warning When running "perf mem record" command on CWF, the below KASAN global-out-of-bounds warning is seen. ================================================================== BUG: KASAN: global-out-of-bounds in cmt_latency_data+0x176/0x1b0 Read of size 4 at addr ffffffffb721d000 by task dtlb/9850 Call Trace: kasan_report+0xb8/0xf0 cmt_latency_data+0x176/0x1b0 setup_arch_pebs_sample_data+0xf49/0x2560 intel_pmu_drain_arch_pebs+0x577/0xb00 handle_pmi_common+0x6c4/0xc80 The issue is caused by below code in __grt_latency_data(). The code tries to access x86_hybrid_pmu structure which doesn't exist on non-hybrid platform like CWF. WARN_ON_ONCE(hybrid_pmu(event->pmu)->pmu_type == hybrid_big) So add is_hybrid() check before calling this WARN_ON_ONCE to fix the global-out-of-bounds access issue. Fixes: 090262439f66 ("perf/x86/intel: Rename model-specific pebs_latency_data functions") Reported-by: Xudong Hao Signed-off-by: Dapeng Mi Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Zide Chen Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20251028064214.1451968-1-dapeng1.mi@linux.intel.com --- arch/x86/events/intel/ds.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c index c0b7ac1c7594e..01bc59e9286cc 100644 --- a/arch/x86/events/intel/ds.c +++ b/arch/x86/events/intel/ds.c @@ -317,7 +317,8 @@ static u64 __grt_latency_data(struct perf_event *event, u64 status, { u64 val; - WARN_ON_ONCE(hybrid_pmu(event->pmu)->pmu_type == hybrid_big); + WARN_ON_ONCE(is_hybrid() && + hybrid_pmu(event->pmu)->pmu_type == hybrid_big); dse &= PERF_PEBS_DATA_SOURCE_GRT_MASK; val = hybrid_var(event->pmu, pebs_data_source)[dse]; -- 2.47.3