[DragonFlyBSD - Bug #3198] OpenGL app crash with Radeon driver

[bugtracker-admin at leaf.dragonflybsd.org]

Issue #3198 has been updated by ftigeot.


The pager read error appears to always be from this chunk of code in ttm/ttm_bo_vm.c around line 550:
```
	/*
	 * Wait for buffer data in transit, due to a pipelined
	 * move.
	 */
	if (test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)) {
		/*
		 * Here, the behavior differs between Linux and FreeBSD.
		 *
		 * On Linux, the wait is interruptible (3rd argument to
		 * ttm_bo_wait). There must be some mechanism to resume
		 * page fault handling, once the signal is processed.
		 *
		 * On FreeBSD, the wait is uninteruptible. This is not a
		 * problem as we can't end up with an unkillable process
		 * here, because the wait will eventually time out.
		 *
		 * An example of this situation is the Xorg process
		 * which uses SIGALRM internally. The signal could
		 * interrupt the wait, causing the page fault to fail
		 * and the process to receive SIGSEGV.
		 */
		ret = ttm_bo_wait(bo, false, false);
		if (unlikely(ret != 0)) {
			retval = VM_PAGER_ERROR;
			goto out_unlock;
		}
	}
```

----------------------------------------
Bug #3198: OpenGL app crash with Radeon driver
http://bugs.dragonflybsd.org/issues/3198#change-13780

* Author: yellowrabbit2010
* Status: New
* Priority: High
* Assignee: 
* Category: Driver
* Target version: 
----------------------------------------
The programs I work with, namely, FreeCAD, Kicad, MPV, Chromium crash with ``vm_fault: pager read error'' at different times, sometimes immediately after starting, sometimes after some manipulations.
I managed to repeat the situation on the configuration with minimal changes:
- I downloaded DragonFly-X86_64-LATEST.img.bz2 2019-07-16 03:56 285M
- installed it on 8G usb flash drive
- modify rc.conf and wpa_supplicant.conf in order to connect to WiFi
- pkg install Xorg mesa-demos
- added user rabbit
- startx 
- glxgears

Glxgears crushed immediately after start. Unfortunately, the test installation does not contain packages with debug information, so its core file is not very informative. But since the situation is always repeated, I built packages with debug information and made a screenshot of the gdb file with the downloaded core on the working machine (KERNCONF=X86_64_GENERIC).
I have to note that I use the core of the March version and it has no problems with graphics at all: there have been no failures for a long time with all the programs listed above. That is, it is unlikely that this is a video memory or swap file problem and so on.
= 5.5-DEVELOPMENT DragonFly v5.5.0.325.gf6792-DEVELOPMENT #25: Sun Mar 24 09:54:07 VLAT 2019 =

I made an image of the flash drive immediately after the failure, you can download it from here https://yellowrabbit.gitlab.io/pub/bugs/dfly-glxgears.img.xz . There are no passwords neither for the rabbit user nor for root.








---Files--------------------------------
IMG_20190718_080950_HDR-min.jpg (1.83 MB)
Xorg.0.log (27.6 KB)
gdb-0.txt (558 Bytes)
messages (34.9 KB)
gdb-1.txt (2.72 KB)
gdb-1.png (394 KB)
glxgears.core.xz (298 KB)
IMG_20190724_210557_HDR-min.jpg (2.57 MB)
vga.txz (312 KB)
IMG_20190727_194932_HDR.jpg (4.11 MB)


-- 
You have received this notification because you have either subscribed to it, or are involved in it.
To change your notification preferences, please click here: http://bugs.dragonflybsd.org/my/account