perf/x86/intel: Validate the return value of intel_pmu_init_hybrid()

The intel_pmu_init_hybrid() function allocates memory for the
x86_pmu.hybrid_pmu[] array. If this allocation fails under memory
pressure, hybrid PMU initialization will fail.

Currently, the caller does not check the return value of
intel_pmu_init_hybrid(). This can lead to a null-pointer dereference or
invalid memory access when attempting to use the uninitialized array,
potentially triggering a system panic.

Fix this by validating the return value of intel_pmu_init_hybrid().
Additionally, reset x86_pmu.num_hybrid_pmus to 0 on failure, and defer
intel_pmu_arch_lbr_init() until after hybrid PMU initialization
succeeds. This reordering avoids the need to explicitly destroy the
kmem cache if the memory allocation fails.

Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260616044654.3468742-6-dapeng1.mi@linux.intel.com

0 files changed, 0 insertions, 0 deletions