From: Mathieu Desnoyers Date: Wed, 30 Nov 2011 18:34:14 +0000 (-0500) Subject: lttng lib: ring buffer: remove stale null-pointer X-Git-Tag: upstream/snapshot3+hdmi~8420^2~101^2~114 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2f8e0b31ad257bca9ff5dda9fdfdcc98d38d97f8;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git lttng lib: ring buffer: remove stale null-pointer * Dan Carpenter wrote: [...] > The patch c844b2f5cfea: "lttng lib: ring buffer" from Nov 28, 2011, > leads to the following Smatch complaint: > > drivers/staging/lttng/lib/ringbuffer/ring_buffer_frontend.c +1150 > +lib_ring_buffer_print_buffer_errors() > warn: variable dereferenced before check 'chan' (see line 1143) > > drivers/staging/lttng/lib/ringbuffer/ring_buffer_frontend.c > 1142 { > 1143 const struct lib_ring_buffer_config *config = > +chan->backend.config; > > +^^^^^^^^^^^^^^^^^^^^ > Dereference. > > 1144 unsigned long write_offset, cons_offset; > 1145 > 1146 /* > 1147 * Can be called in the error path of allocation when > 1148 * trans_channel_data is not yet set. > 1149 */ > 1150 if (!chan) > ^^^^^^^^^ > Check. At first glance the comment seems out of date, I think check can > be removed safely. > > 1151 return; > 1152 /* Reported-by: Dan Carpenter Signed-off-by: Mathieu Desnoyers Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/lttng/lib/ringbuffer/ring_buffer_frontend.c b/drivers/staging/lttng/lib/ringbuffer/ring_buffer_frontend.c index 802f5cd..957d7f3 100644 --- a/drivers/staging/lttng/lib/ringbuffer/ring_buffer_frontend.c +++ b/drivers/staging/lttng/lib/ringbuffer/ring_buffer_frontend.c @@ -1144,12 +1144,6 @@ void lib_ring_buffer_print_buffer_errors(struct lib_ring_buffer *buf, unsigned long write_offset, cons_offset; /* - * Can be called in the error path of allocation when - * trans_channel_data is not yet set. - */ - if (!chan) - return; - /* * No need to order commit_count, write_offset and cons_offset reads * because we execute at teardown when no more writer nor reader * references are left.