On 24-07-15 10:39, Alexey Khoroshilov wrote:
Dear Mike,
On 24.07.2015 14:01, Mike Looijmans wrote:
Regarding this commit:
https://lkml.org/lkml/2014/12/12/709
rsi: fix memory leak in rsi_load_ta_instructions()
Memory allocated by kmemdup() in rsi_load_ta_instructions() is leaked.
But duplication of firmware data here is useless,
so the patch removes kmemdup() at all.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
We use this driver for the Redpine Wifi chip on our "florida" board, and
after this commit it stopped working. Symptom was that the "wlan0"
device was not created at all. Reverting the commit makes it work again.
Apparently, the kmemdup action is needed for something. I suspect the
DMA controller is still copying the firmware data before the method
returned.
To test your hypothesis, could you please check if it is still broken
with kfree(fw); added just after release_firmware(fw_entry); in
rsi_load_ta_instructions().
Tried, and appears to work if i just kfree() the firmware copy. It does leave
a bad taste though. I'd expect fw_entry->data to point to a kmalloc'd area as
well. So it might work now just because it happens to be that the memory if
"far enough away" and isn't being touched by anything else until the transfer
is done. And on some other setup, it may suddenly fail unexpectedly.
I thought to move the kfree to a point where the driver unregisters, but
apparently it doesn't have any internal hook for that (sdio_done or so).
I'd really like to see some comment from the Redpine folks on this, but since
there hasn't been any event in the past year or so, I don't expect much.
Kind regards,
Mike Looijmans
System Expert
TOPIC Embedded Products
Eindhovenseweg 32-C, NL-5683 KH Best
Postbus 440, NL-5680 AK Best
Telefoon: +31 (0) 499 33 69 79
Telefax: +31 (0) 499 33 69 70
E-mail: [email protected]
Website: www.topicproducts.com
Please consider the environment before printing this e-mail
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
