svn commit: r359429 - head/sys/dev/evdev

[Vladimir Kondratyev]

Author: wulf
Date: Sun Mar 29 23:01:36 2020
New Revision: 359429
URL: https://svnweb.freebsd.org/changeset/base/359429

Log:
  evdev: return error rather than zero-length data on blocked read()
  
  if blocked process has been woken up by evdev device destruction.
  
  MFC after:	2 weeks

Modified:
  head/sys/dev/evdev/cdev.c

Modified: head/sys/dev/evdev/cdev.c
==============================================================================
--- head/sys/dev/evdev/cdev.c	Sun Mar 29 23:00:33 2020	(r359428)
+++ head/sys/dev/evdev/cdev.c	Sun Mar 29 23:01:36 2020	(r359429)
@@ -217,6 +217,8 @@ evdev_read(struct cdev *dev, struct uio *uio, int iofl
 				client->ec_blocked = true;
 				ret = mtx_sleep(client, &client->ec_buffer_mtx,
 				    PCATCH, "evread", 0);
+				if (ret == 0 && client->ec_revoked)
+					ret = ENODEV;
 			}
 		}
 	}