Commit 7b568e9e authored by Zide Chen's avatar Zide Chen Committed by Peter Zijlstra
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perf/x86/intel/uncore: Skip discovery table for offline dies 



This warning can be triggered if NUMA is disabled and the system
boots with fewer CPUs than the number of CPUs in die 0.

WARNING: CPU: 9 PID: 7257 at uncore.c:1157 uncore_pci_pmu_register+0x136/0x160 [intel_uncore]

Currently, the discovery table continues to be parsed even if all CPUs
in the associated die are offline.  This can lead to an array overflow
at "pmu->boxes[die] = box" in uncore_pci_pmu_register(), which may
trigger the warning above or cause other issues.

Fixes: edae1f06 ("perf/x86/intel/uncore: Parse uncore discovery tables")
Reported-by: default avatarSteve Wahl <steve.wahl@hpe.com>
Signed-off-by: default avatarZide Chen <zide.chen@intel.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarDapeng Mi <dapeng1.mi@linux.intel.com>
Tested-by: default avatarSteve Wahl <steve.wahl@hpe.com>
Link: https://patch.msgid.link/20260313174050.171704-3-zide.chen@intel.com
parent e2a39d1a

arch/x86/events/intel/uncore_discovery.c

+1 −1
Original line number Diff line number Diff line
@@ -371,7 +371,7 @@ static bool uncore_discovery_pci(struct uncore_discovery_domain *domain) 
				     (val & UNCORE_DISCOVERY_DVSEC2_BIR_MASK) * UNCORE_DISCOVERY_BIR_STEP;



			die = get_device_die_id(dev);

			if (die < 0)

			if ((die < 0) || (die >= uncore_max_dies()))

				continue;



			parse_discovery_table(domain, dev, die, bar_offset, &parsed);