Linux CXL
 help / color / mirror / Atom feed
* [PATCH] cxl/pmu: Ensure put_device on pmu devices
@ 2023-10-16 23:25 Ira Weiny
  2023-10-16 23:43 ` Dave Jiang
  2023-10-18 10:50 ` Jonathan Cameron
  0 siblings, 2 replies; 5+ messages in thread
From: Ira Weiny @ 2023-10-16 23:25 UTC (permalink / raw)
  To: Davidlohr Bueso, Jonathan Cameron, Dave Jiang, Alison Schofield,
	Vishal Verma, Dan Williams
  Cc: linux-cxl, linux-kernel, Jonathan Cameron, Ira Weiny

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: 1ad3f701c399 ("cxl/pci: Find and register CXL PMU devices")
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
---
 drivers/cxl/core/pmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cxl/core/pmu.c b/drivers/cxl/core/pmu.c
index 7684c843e5a5..5d8e06b0ba6e 100644
--- a/drivers/cxl/core/pmu.c
+++ b/drivers/cxl/core/pmu.c
@@ -23,7 +23,7 @@ const struct device_type cxl_pmu_type = {
 
 static void remove_dev(void *dev)
 {
-	device_del(dev);
+	device_unregister(dev);
 }
 
 int devm_cxl_pmu_add(struct device *parent, struct cxl_pmu_regs *regs,

---
base-commit: 58720809f52779dc0f08e53e54b014209d13eebb
change-id: 20231016-pmu-unregister-fix-345480926a58

Best regards,
-- 
Ira Weiny <ira.weiny@intel.com>


^ permalink raw reply related	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2023-10-18 10:50 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-10-16 23:25 [PATCH] cxl/pmu: Ensure put_device on pmu devices Ira Weiny
2023-10-16 23:43 ` Dave Jiang
2023-10-17 15:35   ` Ira Weiny
2023-10-17 16:21     ` Dave Jiang
2023-10-18 10:50 ` Jonathan Cameron

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox