[PATCH] firmware: request_firmware() should propagate -ERESTARTSYS

From: Martin Fuzzey
Date: Tue May 23 2017 - 09:49:55 EST


When -ERESTARTSYS is returned by wait_* due to a signal this should
be returned from request_firmware() so that the syscall may be
restarted if necessary.

Without this it is not possible to distinguish the case of
request_firmware() failing due to a timeout with that due to a signal.

In my particular case request_firmware() was being called from
a sysfs .store() callback and the writing process was the
Android init process which received a SIGCHLD causing
request_firmware() to fail.

Signed-off-by: Martin Fuzzey <mfuzzey@xxxxxxxxxxx>
---
drivers/base/firmware_class.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index b616bf7..13ed62f 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -1023,9 +1023,10 @@ static int _request_firmware_load(struct firmware_priv *fw_priv,
mutex_unlock(&fw_lock);
}

- if (fw_state_is_aborted(&buf->fw_st))
- retval = -EAGAIN;
- else if (buf->is_paged_buf && !buf->data)
+ if (fw_state_is_aborted(&buf->fw_st)) {
+ if (retval != -ERESTARTSYS)
+ retval = -EAGAIN;
+ } else if (buf->is_paged_buf && !buf->data)
retval = -ENOMEM;

device_del(f_dev);