powercap: intel_rapl: Fix kernel panic during PMU unbind

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rapl_package_add_pmu() fails internally at perf_pmu_register(),
and rapl_pmu_update() leaves the global rapl_pmu.pmu structure
zero-initialized via memset and returns an error. But any
previously probed packages retain has_pmu = true.

When the driver is subsequently unbound or removed,
rapl_package_remove_pmu_locked() sees has_pmu == true and
unconditionally calls perf_pmu_unregister(&rapl_pmu.pmu) on the
zeroed-out structure. This attempts a list_del_rcu() on a NULL
list head, immediately causing a kernel panic.

Fix this by checking if the PMU is actually registered before
attempting to unregister it.

Signed-off-by: Sumeet Pawnikar <sumeet4linux@gmail.com>
Reviewed-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
[ rjw: Added empty line after the new conditional ]
Link: https://patch.msgid.link/20260822094657.12489-1-sumeet4linux@gmail.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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Sumeet Pawnikar 2026-08-22 15:16:57 +05:30 • committed by Rafael J. Wysocki

parent a8b842366f

commit 916b61abba

1 changed files with 3 additions and 1 deletions

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drivers/powercap/intel_rapl_common.c

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