This is a note to let you know that I've just added the patch titled perf/x86/intel/uncore: Fix reference count leak in __uncore_imc_init_box() to the 6.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: perf-x86-intel-uncore-fix-reference-count-leak-in-__.patch and it can be found in the queue-6.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 81792c3fa0f2ff83b964ef429184f32d757b793d Author: Xiongfeng Wang <wangxiongfeng2@xxxxxxxxxx> Date: Fri Nov 18 14:31:37 2022 +0800 perf/x86/intel/uncore: Fix reference count leak in __uncore_imc_init_box() [ Upstream commit 17b8d847b92d815d1638f0de154654081d66b281 ] 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: fdb64822443e ("perf/x86: Add Intel Tiger Lake uncore support") Signed-off-by: Xiongfeng Wang <wangxiongfeng2@xxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20221118063137.121512-5-wangxiongfeng2@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/x86/events/intel/uncore_snb.c b/arch/x86/events/intel/uncore_snb.c index 1ef4f7861e2e..1f4869227efb 100644 --- a/arch/x86/events/intel/uncore_snb.c +++ b/arch/x86/events/intel/uncore_snb.c @@ -1338,6 +1338,7 @@ static void __uncore_imc_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); @@ -1352,6 +1353,8 @@ static void __uncore_imc_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 void tgl_uncore_imc_freerunning_init_box(struct intel_uncore_box *box)