Hi Wolfram,

On Jan 19, 2015, at 20:55 , Wolfram Sang [off-list ref] wrote:
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Back in the days, sysfs seemed to have refcounting issues and =

subsystems

needed a completion to be safe. This is not the case anymore, so I2C =

can

get rid of this code. There is noone else besides I2C doing something
like this currently (checked with the attached coccinelle script which
checks if a release function exists and if it contains a completion).
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I have been digging through the history of linux.git and
linux-history.git and found that e.g. w1 used to have such a mechanism
and also simply removed it later.
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Some more info from Greg Kroah-Hartman:
"Having that call "wait" for the other release call to happen is =

really

old, as Jean points out, from 2003.  We have "fixed" sysfs since then =

to

detach the files from the devices easier, we used to have some nasy
reference count issues in that area."
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And some testing from Jean Delvare which matches my results:
"However I just tested unloading an i2c bus driver while its adapter's
new_device attribute was opened and rmmod returned immediately. So it
doesn't look like accessing sysfs attributes actually takes a =

reference

to the underlying i2c_adapter."
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Let's get rid of this code before really nobody knows/understands
anymore what this was for and if it has a subtle use.
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Hehe, rather obliquely tested by me too :)

Please save the reference counter hackers sanity and merge this :)

Reported-by: Pantelis Antoniou <redacted>
Signed-off-by: Wolfram Sang <redacted>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jean Delvare <redacted>
Cc: Julia Lawall <redacted>
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Regards

=E2=80=94 Pantelis=