From: Yun Zhou yun.zhou@windriver.com
stable inclusion from linux-4.19.198 commit c2e99a8d37b90b35d7d904c86fd125375ebec2b4
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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: Yang Yingliang yangyingliang@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 bd807f545a9d7..b15dbb6f061a5 100644 --- a/lib/seq_buf.c +++ b/lib/seq_buf.c @@ -242,12 +242,14 @@ 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; }