From e6154e4cb8b0d3692f84ca0d66b4e1ba0389b134 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 7 Dec 2018 11:05:54 +0000 Subject: drm/i915: Skip the ERR_PTR error state Although commit fb6f0b64e455 ("drm/i915: Prevent machine hang from Broxton's vtd w/a and error capture") applied cleanly after a 24 month hiatus, the code had moved on with new methods for peeking and fetching the captured gpu info. Make sure we catch all uses of the stashed error state and avoid dereferencing the error pointer. v2: Move error pointer determination into i915_gpu_capture_state v3: Restore early check to avoid capturing and then throwing away subsequent GPU error states. Fixes: fb6f0b64e455 ("drm/i915: Prevent machine hang from Broxton's vtd w/a and error capture") Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Cc: Joonas Lahtinen Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20181207110554.19897-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_sysfs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/gpu/drm/i915/i915_sysfs.c') diff --git a/drivers/gpu/drm/i915/i915_sysfs.c b/drivers/gpu/drm/i915/i915_sysfs.c index 535caebd9813..c0cfe7ae2ba5 100644 --- a/drivers/gpu/drm/i915/i915_sysfs.c +++ b/drivers/gpu/drm/i915/i915_sysfs.c @@ -521,7 +521,9 @@ static ssize_t error_state_read(struct file *filp, struct kobject *kobj, ssize_t ret; gpu = i915_first_error_state(i915); - if (gpu) { + if (IS_ERR(gpu)) { + ret = PTR_ERR(gpu); + } else if (gpu) { ret = i915_gpu_state_copy_to_buffer(gpu, buf, off, count); i915_gpu_state_put(gpu); } else { -- cgit v1.2.3