svn commit: r296720 - head/sys/dev/drm2/i915

[Jean-Sébastien Pédron]

Author: dumbbell
Date: Sat Mar 12 11:54:58 2016
New Revision: 296720
URL: https://svnweb.freebsd.org/changeset/base/296720

Log:
  drm/i915: Fix page fault handler failure
  
  ... when __wait_seqno() is interrupted by a signal. In this case,
  __wait_seqno() returns -ERESTARTSYS. Like we already do in drm_ioctl(),
  we need to convert this error to a common code such as -EINTR, so the
  page fault handler is restarted.
  
  Reported by:	Frederic Chardon <chardon.frederic at gmail.com>
  Tested by:	Frederic Chardon <chardon.frederic at gmail.com>

Modified:
  head/sys/dev/drm2/i915/i915_gem.c

Modified: head/sys/dev/drm2/i915/i915_gem.c
==============================================================================
--- head/sys/dev/drm2/i915/i915_gem.c	Sat Mar 12 09:44:23 2016	(r296719)
+++ head/sys/dev/drm2/i915/i915_gem.c	Sat Mar 12 11:54:58 2016	(r296720)
@@ -1619,6 +1619,13 @@ out:
 	KASSERT(ret != 0, ("i915_gem_pager_fault: wrong return"));
 	CTR4(KTR_DRM, "fault_fail %p %jx %x err %d", gem_obj, offset, prot,
 	    -ret);
+	if (ret == -ERESTARTSYS) {
+		/*
+		 * NOTE Linux<->FreeBSD: Convert Linux' -ERESTARTSYS to
+		 * the more common -EINTR, so the page fault is retried.
+		 */
+		ret = -EINTR;
+	}
 	if (ret == -EAGAIN || ret == -EIO || ret == -EINTR) {
 		kern_yield(PRI_USER);
 		goto retry;