PM: hibernate: Emit an error when image writing fails

If image writing fails, a return code is passed up to the caller, but
none of the callers log anything to the log and so the only record
of it is the return code that userspace gets.

Adjust the logging so that the image size and speed of writing is
only emitted on success and if there is an error, it's saved to the
logs.

Fixes: a06c6f5d3cc9 ("PM: hibernate: Move to crypto APIs for LZO compression")
Reported-by: Askar Safin <safinaskar@gmail.com>
Closes: https://lore.kernel.org/linux-pm/20251105180506.137448-1-safinaskar@gmail.com/
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Tested-by: Askar Safin <safinaskar@gmail.com>
Cc: 6.9+ <stable@vger.kernel.org> # 6.9+
[ rjw: Added missing braces after "else", changelog edits ]
Link: https://patch.msgid.link/20251106045158.3198061-2-superm1@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 0beff7eeaabaf82e37b7613a1e00f49b36f52976..7daa716d2cb13138c3b16f21b8c7b4aaa3969a94 100644 (file)
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -877,11 +877,14 @@ out_finish:
        stop = ktime_get();
        if (!ret)
                ret = err2;
-       if (!ret)
+       if (!ret) {
+               swsusp_show_speed(start, stop, nr_to_write, "Wrote");
+               pr_info("Image size after compression: %d kbytes\n",
+                       (atomic_read(&compressed_size) / 1024));
                pr_info("Image saving done\n");
-       swsusp_show_speed(start, stop, nr_to_write, "Wrote");
-       pr_info("Image size after compression: %d kbytes\n",
-               (atomic_read(&compressed_size) / 1024));
+       } else {
+               pr_err("Image saving failed: %d\n", ret);
+       }
 
 out_clean:
        hib_finish_batch(&hb);