5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Daniel Thompson <daniel.thompson@xxxxxxxxxx> commit db2f9c7dc29114f531df4a425d0867d01e1f1e28 upstream. Currently, if the cursor position is not at the end of the command buffer and the user uses the Tab-complete functions, then the console does not leave the cursor in the correct position. For example consider the following buffer with the cursor positioned at the ^: md kdb_pro 10 ^ Pressing tab should result in: md kdb_prompt_str 10 ^ However this does not happen. Instead the cursor is placed at the end (after then 10) and further cursor movement redraws incorrectly. The same problem exists when we double-Tab but in a different part of the code. Fix this by sending a carriage return and then redisplaying the text to the left of the cursor. Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Tested-by: Justin Stitt <justinstitt@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240424-kgdb_read_refactor-v3-3-f236dbe9828d@xxxxxxxxxx Signed-off-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/debug/kdb/kdb_io.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/kernel/debug/kdb/kdb_io.c +++ b/kernel/debug/kdb/kdb_io.c @@ -370,6 +370,8 @@ poll_again: kdb_printf("\n"); kdb_printf(kdb_prompt_str); kdb_printf("%s", buffer); + if (cp != lastchar) + kdb_position_cursor(kdb_prompt_str, buffer, cp); } else if (tab != 2 && count > 0) { /* How many new characters do we want from tmpbuffer? */ len_tmp = strlen(p_tmp) - len; @@ -383,6 +385,9 @@ poll_again: kdb_printf("%s", cp); cp += len_tmp; lastchar += len_tmp; + if (cp != lastchar) + kdb_position_cursor(kdb_prompt_str, + buffer, cp); } } kdb_nextline = 1; /* reset output line number */