This is a note to let you know that I've just added the patch titled
cxl/pmu: Ensure put_device on pmu devices
to the 6.6-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:
cxl-pmu-ensure-put_device-on-pmu-devices.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 13e21064eeff6b62df3a4c867cd232e768aea0e8
Author: Ira Weiny <ira.weiny@xxxxxxxxx>
Date: Mon Oct 16 16:25:05 2023 -0700
cxl/pmu: Ensure put_device on pmu devices
[ Upstream commit ef3d5cf9c59cccb012aa6b93d99f4c6eb5d6648e ]
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@xxxxxxxxxx>
Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Link: https://lore.kernel.org/r/20231016-pmu-unregister-fix-v1-1-1e2eb2fa3c69@xxxxxxxxx
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/cxl/core/pmu.c b/drivers/cxl/core/pmu.c
index 7684c843e5a59..5d8e06b0ba6e8 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,
