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2925c2fdf1
Currently the first thing we do in cxl_probe is to grab a reference
on the pci device. Later on, we call device_register on our adapter.
In our remove path, we call device_unregister, but we never call
pci_dev_put. We therefore leak the device every time we do a
reflash.
device_register/unregister is sufficient to hold the reference.
Therefore, drop the call to pci_dev_get.
Here's why this is safe.
The proposed cxl_probe(pdev) calls cxl_adapter_init:
a) init calls cxl_adapter_alloc, which creates a struct cxl,
conventionally called adapter. This struct contains a
device entry, adapter->dev.
b) init calls cxl_configure_adapter, where we set
adapter->dev.parent = &dev->dev (here dev is the pci dev)
So at this point, the cxl adapter's device's parent is the PCI
device that I want to be refcounted properly.
c) init calls cxl_register_adapter
*) cxl_register_adapter calls device_register(&adapter->dev)
So now we're in device_register, where dev is the adapter device, and
we want to know if the PCI device is safe after we return.
device_register(&adapter->dev) calls device_initialize() and then
device_add().
device_add() does a get_device(). device_add() also explicitly grabs
the device's parent, and calls get_device() on it:
parent = get_device(dev->parent);
So therefore, device_register() takes a lock on the parent PCI dev,
which is what pci_dev_get() was guarding. pci_dev_get() can therefore
be safely removed.
Fixes:
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||
|---|---|---|
| .. | ||
| altera-stapl | ||
| c2port | ||
| cb710 | ||
| cxl | ||
| echo | ||
| eeprom | ||
| genwqe | ||
| ibmasm | ||
| lis3lv02d | ||
| mei | ||
| mic | ||
| sgi-gru | ||
| sgi-xp | ||
| ti-st | ||
| vmw_vmci | ||
| ad525x_dpot-i2c.c | ||
| ad525x_dpot-spi.c | ||
| ad525x_dpot.c | ||
| ad525x_dpot.h | ||
| apds990x.c | ||
| apds9802als.c | ||
| arm-charlcd.c | ||
| atmel_tclib.c | ||
| atmel-ssc.c | ||
| bh1770glc.c | ||
| bh1780gli.c | ||
| bmp085-i2c.c | ||
| bmp085-spi.c | ||
| bmp085.c | ||
| bmp085.h | ||
| cs5535-mfgpt.c | ||
| ds1682.c | ||
| dummy-irq.c | ||
| enclosure.c | ||
| fsa9480.c | ||
| hmc6352.c | ||
| hpilo.c | ||
| hpilo.h | ||
| ics932s401.c | ||
| ioc4.c | ||
| isl29003.c | ||
| isl29020.c | ||
| Kconfig | ||
| kgdbts.c | ||
| lattice-ecp3-config.c | ||
| lkdtm.c | ||
| Makefile | ||
| pch_phub.c | ||
| phantom.c | ||
| pti.c | ||
| qcom-coincell.c | ||
| spear13xx_pcie_gadget.c | ||
| sram.c | ||
| ti_dac7512.c | ||
| tifm_7xx1.c | ||
| tifm_core.c | ||
| tsl2550.c | ||
| vexpress-syscfg.c | ||
| vmw_balloon.c | ||