From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx>
When not using read_zpage, and reading from a temporary file, the offsets
are not accounted for properly. That is, it uses the offset of the
location of the trace.dat file to map the temporary file (that starts at
offset zero).
Account for mapping of the temporary file when appropriate.
Reported-by: Johannes Berg <johannes@xxxxxxxxxxxxxxxx>
Fixes: add83e0c8b51 ("trace-cmd library: Fix tracecmd_read_at()")
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
lib/trace-cmd/trace-input.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/lib/trace-cmd/trace-input.c b/lib/trace-cmd/trace-input.c
index c181c7d93be4..0fef2ca7bb70 100644
--- a/lib/trace-cmd/trace-input.c
+++ b/lib/trace-cmd/trace-input.c
@@ -1401,8 +1401,11 @@ static void *allocate_page_map(struct tracecmd_input *handle,
int ret;
int fd;
- if (handle->cpu_compressed && handle->read_zpage)
- return read_zpage(handle, cpu, offset);
+ if (handle->cpu_compressed) {
+ if (handle->read_zpage)
+ return read_zpage(handle, cpu, offset);
+ offset -= cpu_data->file_offset;
+ }
if (handle->read_page) {
map = malloc(handle->page_size);
@@ -1419,7 +1422,7 @@ static void *allocate_page_map(struct tracecmd_input *handle,
map_size = handle->page_map_size;
map_offset = offset & ~(map_size - 1);
- if (map_offset < cpu_data->file_offset) {
+ if (!handle->cpu_compressed && map_offset < cpu_data->file_offset) {
map_size -= cpu_data->file_offset - map_offset;
map_offset = cpu_data->file_offset;
}
@@ -1442,10 +1445,9 @@ static void *allocate_page_map(struct tracecmd_input *handle,
map_size -= map_offset + map_size -
(cpu_data->file_offset + cpu_data->file_size);
- if (cpu_data->compress.fd >= 0) {
- map_offset -= cpu_data->file_offset;
+ if (cpu_data->compress.fd >= 0)
fd = cpu_data->compress.fd;
- } else
+ else
fd = handle->fd;
again:
page_map->size = map_size;
--
2.35.1
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