Hello Hans Verkuil, This is a semi-automatic email about new static checker warnings. The patch 254902b01d2a: "[media] gspca: Fix locking issues related to suspend/resume" from May 6, 2012, leads to the following Smatch complaint: drivers/media/video/gspca/sq905c.c:176 sq905c_dostream() warn: variable dereferenced before check 'gspca_dev->dev' (see line 180) drivers/media/video/gspca/sq905c.c 158 /* Request the header, which tells the size to download */ 159 ret = usb_bulk_msg(gspca_dev->dev, 160 usb_rcvbulkpipe(gspca_dev->dev, 0x81), ^^^^^^^^^^^^^^ Derereference inside the calls to usb_bulk_msg() and usb_rcvbulkpipe(). 161 buffer, FRAME_HEADER_LEN, &act_len, 162 SQ905C_DATA_TIMEOUT); 163 PDEBUG(D_STREAM, 164 "Got %d bytes out of %d for header", 165 act_len, FRAME_HEADER_LEN); 166 if (ret < 0 || act_len < FRAME_HEADER_LEN) 167 goto quit_stream; 168 /* size is read from 4 bytes starting 0x40, little endian */ 169 bytes_left = buffer[0x40]|(buffer[0x41]<<8)|(buffer[0x42]<<16) 170 |(buffer[0x43]<<24); 171 PDEBUG(D_STREAM, "bytes_left = 0x%x", bytes_left); 172 /* We keep the header. It has other information, too. */ 173 packet_type = FIRST_PACKET; 174 gspca_frame_add(gspca_dev, packet_type, 175 buffer, FRAME_HEADER_LEN); 176 while (bytes_left > 0 && gspca_dev->dev) { ^^^^^^^^^^^^^^ New check. 177 data_len = bytes_left > SQ905C_MAX_TRANSFER ? 178 SQ905C_MAX_TRANSFER : bytes_left; 179 ret = usb_bulk_msg(gspca_dev->dev, 180 usb_rcvbulkpipe(gspca_dev->dev, 0x81), ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Some more dereferences here. 181 buffer, data_len, &act_len, 182 SQ905C_DATA_TIMEOUT); 183 if (ret < 0 || act_len < data_len) 184 goto quit_stream; 185 PDEBUG(D_STREAM, 186 "Got %d bytes out of %d for frame", 187 data_len, bytes_left); 188 bytes_left -= data_len; 189 if (bytes_left == 0) 190 packet_type = LAST_PACKET; 191 else 192 packet_type = INTER_PACKET; 193 gspca_frame_add(gspca_dev, packet_type, 194 buffer, data_len); 195 } regards, dan carpenter -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html