1
linux/drivers/cxl/core/pmu.c
Ira Weiny ef3d5cf9c5 cxl/pmu: Ensure put_device on pmu devices
The following kmemleaks were detected when removing the cxl module
stack:

unreferenced object 0xffff88822616b800 (size 1024):
...
  backtrace:
    [<00000000bedc6f83>] kmalloc_trace+0x26/0x90
    [<00000000448d1afc>] devm_cxl_pmu_add+0x3a/0x110 [cxl_core]
    [<00000000ca3bfe16>] 0xffffffffa105213b
    [<00000000ba7f78dc>] local_pci_probe+0x41/0x90
    [<000000005bb027ac>] pci_device_probe+0xb0/0x1c0
...
unreferenced object 0xffff8882260abcc0 (size 16):
...
  hex dump (first 16 bytes):
    70 6d 75 5f 6d 65 6d 30 2e 30 00 26 82 88 ff ff  pmu_mem0.0.&....
  backtrace:
...
    [<00000000152b5e98>] dev_set_name+0x43/0x50
    [<00000000c228798b>] devm_cxl_pmu_add+0x102/0x110 [cxl_core]
    [<00000000ca3bfe16>] 0xffffffffa105213b
    [<00000000ba7f78dc>] local_pci_probe+0x41/0x90
    [<000000005bb027ac>] pci_device_probe+0xb0/0x1c0
...
unreferenced object 0xffff8882272af200 (size 256):
...
  backtrace:
    [<00000000bedc6f83>] kmalloc_trace+0x26/0x90
    [<00000000a14d1813>] device_add+0x4ea/0x890
    [<00000000a3f07b47>] devm_cxl_pmu_add+0xbe/0x110 [cxl_core]
    [<00000000ca3bfe16>] 0xffffffffa105213b
    [<00000000ba7f78dc>] local_pci_probe+0x41/0x90
    [<000000005bb027ac>] pci_device_probe+0xb0/0x1c0
...

devm_cxl_pmu_add() correctly registers a device remove function but it
only calls device_del() which is only part of device unregistration.

Properly call device_unregister() to free up the memory associated with
the device.

Fixes: 1ad3f701c3 ("cxl/pci: Find and register CXL PMU devices")
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20231016-pmu-unregister-fix-v1-1-1e2eb2fa3c69@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-12-14 21:54:45 -08:00

69 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2023 Huawei. All rights reserved. */
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/idr.h>
#include <cxlmem.h>
#include <pmu.h>
#include <cxl.h>
#include "core.h"
static void cxl_pmu_release(struct device *dev)
{
struct cxl_pmu *pmu = to_cxl_pmu(dev);
kfree(pmu);
}
const struct device_type cxl_pmu_type = {
.name = "cxl_pmu",
.release = cxl_pmu_release,
};
static void remove_dev(void *dev)
{
device_unregister(dev);
}
int devm_cxl_pmu_add(struct device *parent, struct cxl_pmu_regs *regs,
int assoc_id, int index, enum cxl_pmu_type type)
{
struct cxl_pmu *pmu;
struct device *dev;
int rc;
pmu = kzalloc(sizeof(*pmu), GFP_KERNEL);
if (!pmu)
return -ENOMEM;
pmu->assoc_id = assoc_id;
pmu->index = index;
pmu->type = type;
pmu->base = regs->pmu;
dev = &pmu->dev;
device_initialize(dev);
device_set_pm_not_required(dev);
dev->parent = parent;
dev->bus = &cxl_bus_type;
dev->type = &cxl_pmu_type;
switch (pmu->type) {
case CXL_PMU_MEMDEV:
rc = dev_set_name(dev, "pmu_mem%d.%d", assoc_id, index);
break;
}
if (rc)
goto err;
rc = device_add(dev);
if (rc)
goto err;
return devm_add_action_or_reset(parent, remove_dev, dev);
err:
put_device(&pmu->dev);
return rc;
}
EXPORT_SYMBOL_NS_GPL(devm_cxl_pmu_add, CXL);