From: Yun Zhou <yun.zhou@windriver.com> stable inclusion from stable-5.10.50 commit c556b938b3be1bb8403ae2fae34d87fd4549a6a3 bugzilla: 174522 https://gitee.com/openeuler/kernel/issues/I4DNFY Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 6a2cbc58d6c9d90cd74288cc497c2b45815bc064 upstream. Since the raw memory 'data' does not go forward, it will dump repeated data if the data length is more than 8. If we want to dump longer data blocks, we need to repeatedly call macro SEQ_PUT_HEX_FIELD. I think it is a bit redundant, and multiple function calls also affect the performance. Link: https://lore.kernel.org/lkml/20210625122453.5e2fe304@oasis.local.home/ Link: https://lkml.kernel.org/r/20210626032156.47889-2-yun.zhou@windriver.com Cc: stable@vger.kernel.org Fixes: 6d2289f3faa7 ("tracing: Make trace_seq_putmem_hex() more robust") Signed-off-by: Yun Zhou <yun.zhou@windriver.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- lib/seq_buf.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/lib/seq_buf.c b/lib/seq_buf.c index 707453f5d58e..89c26c393bdb 100644 --- a/lib/seq_buf.c +++ b/lib/seq_buf.c @@ -243,12 +243,14 @@ int seq_buf_putmem_hex(struct seq_buf *s, const void *mem, break; /* j increments twice per loop */ - len -= j / 2; hex[j++] = ' '; seq_buf_putmem(s, hex, j); if (seq_buf_has_overflowed(s)) return -1; + + len -= start_len; + data += start_len; } return 0; } -- 2.20.1