4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiri Olsa <jolsa@xxxxxxxxxx> [ Upstream commit fa1195ccc0af2d121abe0fe266a1caee8c265eea ] We need to increase output offset in each iteration, not decrease it as we currently do. I guess we were lucky to finish in most cases in first iteration, so the bug never showed. However it shows a lot when working with big (~4GB) size data. Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: David Ahern <dsahern@xxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Fixes: 9c9f5a2f1944 ("perf tools: Introduce copyfile_offset() function") Link: http://lkml.kernel.org/r/20180109133923.25406-1-jolsa@xxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/perf/util/util.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/tools/perf/util/util.c +++ b/tools/perf/util/util.c @@ -196,7 +196,7 @@ int copyfile_offset(int ifd, loff_t off_ size -= ret; off_in += ret; - off_out -= ret; + off_out += ret; } munmap(ptr, off_in + size);