Date: Fri, 16 Jun 2017 17:01:42 +0800 From: Jia-Ju Bai <baijiaju1990@163.com> To: freebsd-drivers@freebsd.org, freebsd-net@freebsd.org Subject: [Bug 220033] [if_ixgb] sys/dev/ixgb/if_ixgb.c: a sleep-under-mutex bug in ixge_get_buf Message-ID: <4f7481c7-f70b-a76d-2169-8e57f9ba3cb8@163.com>
next in thread | raw e-mail | index | archive | help
The ixgb driver may sleep under a mutex, and the function call path in file
"sys/dev/ixgb/if_ixgb.c" in FreeBSD 11.0 is:
ixgb_init [line 750: acquire the mutex]
ixgb_init_locked [line 751]
ixgb_setup_receive_structures [line 699]
ixgb_allocate_receive_structures [line 1913]
ixgb_get_buf [line 1885]
bus_dmamap_load(BUS_DMA_WAITOK) [line 1812] --> may sleep
The possible fix of these bugs is to set the last parameter in bus_dmamap_load
to "BUS_DMA_NOWAIT".
This bug is found by a static analysis tool written by myself, and it is
checked by my review of the FreeBSD code.
By the way, I am a freshman in developing FreeBSD drivers, and I am willing to
submit a patch. But I do not know how to write and submit a patch, and where to
submit, so I am looking forward to useful advice :)
Jia-Ju Bai
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4f7481c7-f70b-a76d-2169-8e57f9ba3cb8>