From: Daniel Thompson <daniel.thompson@linaro.org> stable inclusion from stable-v6.6.34 commit 958ba65a35905e9bb55d1bce245e060fbe751632 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IAD6H2 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- 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@vger.kernel.org Reviewed-by: Douglas Anderson <dianders@chromium.org> Tested-by: Justin Stitt <justinstitt@google.com> Link: https://lore.kernel.org/r/20240424-kgdb_read_refactor-v3-3-f236dbe9828d@lina... Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Wang Hai <wanghai38@huawei.com> --- kernel/debug/kdb/kdb_io.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c index 50789c99b3ba..5fccb46f399e 100644 --- a/kernel/debug/kdb/kdb_io.c +++ b/kernel/debug/kdb/kdb_io.c @@ -383,6 +383,8 @@ static char *kdb_read(char *buffer, size_t bufsize) 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; @@ -396,6 +398,9 @@ static char *kdb_read(char *buffer, size_t bufsize) 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 */ -- 2.17.1