lib/igt_gt: Handle SIGINT whilst writing to i915_error_state

Becareful in case we try and eat the error state whilst interrupts are
being sent and repeat the write() until we finish uninterrupted.

References: https://bugs.freedesktop.org/show_bug.cgi?id=94573
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 6 insertions, 2 deletions

diff --git a/lib/igt_gt.c b/lib/igt_gt.c
index c7e16e35..d2ae0587 100644
--- a/lib/igt_gt.c
+++ b/lib/igt_gt.c
@@ -225,10 +225,14 @@ igt_hang_ring_t igt_hang_ring(int fd, int ring)
 
 static void eat_error_state(void)
 {
-	int fd;
+	int fd, ret;
 
 	fd = igt_debugfs_open("i915_error_state", O_WRONLY);
-	igt_assert(write(fd, "", 1) == 1);
+	do {
+		ret = write(fd, "", 1);
+		if (ret < 0)
+			ret = -errno;
+	} while (ret == -EINTR || ret == -EAGAIN);
 	close(fd);
 }