Hi, Scenario: After SD card is inserted and partitions are mounted, start transferring a large media file (for ex: 200MB) to SD. Remove the card in between. Problem: There is a huge delay of ~20secs when the user get notified about the card removal. This delay depends on the size of the file to be transferred. dmesg shows continuous I/O errors even after card removal notification (card xxxx removed in MMC layer) ============================== [ 3182.791614] mmcblk0: error -123 sending status comand [ 3182.791619] mmcblk0: error -123 sending read/write command, response 0x0, card status 0x0 [ 3182.803637] mmcblk0: error -123 requesting status [ 3182.805658] end_request: I/O error, dev mmcblk0, sector 1527146 [ 3182.805665] end_request: I/O error, dev mmcblk0, sector 1527154 [ 3182.805670] end_request: I/O error, dev mmcblk0, sector 1527162 [ 3182.805675] end_request: I/O error, dev mmcblk0, sector 1527170 [ 3182.805680] end_request: I/O error, dev mmcblk0, sector 1527178 [ 3182.805684] end_request: I/O error, dev mmcblk0, sector 1527186 [ 3182.805689] end_request: I/O error, dev mmcblk0, sector 1527194 [ 3182.805694] end_request: I/O error, dev mmcblk0, sector 1527202 [ 3182.805699] end_request: I/O error, dev mmcblk0, sector 1527210 [ 3182.805704] end_request: I/O error, dev mmcblk0, sector 1527218 [ 3182.805708] end_request: I/O error, dev mmcblk0, sector 1527226 [ 3182.805713] end_request: I/O error, dev mmcblk0, sector 1527234 [ 3182.805717] end_request: I/O error, dev mmcblk0, sector 1527242 [ 3182.805722] end_request: I/O error, dev mmcblk0, sector 1527250 [ 3182.805727] end_request: I/O error, dev mmcblk0, sector 1527258 [ 3182.805731] end_request: I/O error, dev mmcblk0, sector 1527266 ==================================== I have observed that del_gendisk() called in mmc_blk_remove() to stop new requests getting into the queue contributes much to the delay. While flushing the requests there are still requests coming to process (which fail as there is no card hence these errors). Isn't there any notifier mechanism for VFS to know when the card is removed and as soon as this card is removed new requests are flushed immediately without any delay. BTW I am using 2.6.35 kernel version and formatted the SD card with FAT (also tried with ext3 but not much of difference seen). Card insertion and removal is interrupt based. Thanks Sujit -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
