perf/x86/intel/uncore: Fix reference count leak in __uncore_imc_init_…

…box()

[ Upstream commit 17b8d84 ]

pci_get_device() will increase the reference count for the returned
pci_dev, so tgl_uncore_get_mc_dev() will return a pci_dev with its
reference count increased. We need to call pci_dev_put() to decrease the
reference count before exiting from __uncore_imc_init_box(). Add
pci_dev_put() for both normal and error path.

Fixes: fdb6482 ("perf/x86: Add Intel Tiger Lake uncore support")
Signed-off-by: Xiongfeng Wang <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Kan Liang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sasha Levin <[email protected]>

arch/x86/events/intel/uncore_snb.c

@@ -1423,6 +1423,7 @@ static void tgl_uncore_imc_freerunning_init_box(struct intel_uncore_box *box)
 	/* MCHBAR is disabled */
 	if (!(mch_bar & BIT(0))) {
 		pr_warn("perf uncore: MCHBAR is disabled. Failed to map IMC free-running counters.\n");
+		pci_dev_put(pdev);
 		return;
 	}
 	mch_bar &= ~BIT(0);
@@ -1436,6 +1437,8 @@ static void tgl_uncore_imc_freerunning_init_box(struct intel_uncore_box *box)
 	box->io_addr = ioremap(addr, type->mmio_map_size);
 	if (!box->io_addr)
 		pr_warn("perf uncore: Failed to ioremap for %s.\n", type->name);
+
+	pci_dev_put(pdev);
 }
 
 static struct intel_uncore_ops tgl_uncore_imc_freerunning_ops = {