[Intel-gfx] [PATCH igt] lib: Check and report if a subtest triggers a new kernel taint

[Chris Wilson]

Quoting Chris Wilson (2017-11-29 12:30:23)
> Checking for a tainted kernel is a convenient way to see if the test
> generated a critical error such as a oops, or machine check.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Cc: Radoslaw Szwichtenberg <radoslaw.szwichtenberg at intel.com>
> ---
> diff --git a/lib/igt_kernel_taint.c b/lib/igt_kernel_taint.c
> new file mode 100644
> index 00000000..86d9cd20
> --- /dev/null
> +++ b/lib/igt_kernel_taint.c
> @@ -0,0 +1,95 @@
> +/*
> + * Copyright 2017 Intel Corporation
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the next
> + * paragraph) shall be included in all copies or substantial portions of the
> + * Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
> + * IN THE SOFTWARE.
> + */
> +
> +#include <unistd.h>
> +#include <fcntl.h>
> +
> +#include "igt.h"
> +#include "igt_kernel_taint.h"
> +#include "igt_sysfs.h"
> +
> +#define BIT(x) (1ul << (x))
> +
> +static const struct kernel_taint {
> +       const char *msg;
> +       unsigned int flags;
> +} taints[] = {
> +       { "Non-GPL module loaded" },
> +       { "Forced module load" },
> +       { "Unsafe SMP processor" },
> +       { "Forced module unload" },
> +       { "Machine Check Exception", TAINT_WARN },
> +       { "Bad page detected", TAINT_ERROR },
> +       { "Tainted by user request", TAINT_WARN },

Since unsafe modparams generate these and we are still using them
extensively, we should probably ignore this one.

> +       { "System is on fire", TAINT_ERROR },
> +       { "ACPI DSDT has been overridden by user" },
> +       { "OOPS", TAINT_ERROR },
> +       { "Staging driver loaded; are you mad?" },
> +       { "Severe firmware bug workaround active", TAINT_WARN },
> +       { "Out-of-tree module loaded" },
> +       { "Unsigned module loaded" },
> +       { "Soft-lockup detected", TAINT_WARN },
> +       { "Kernel has been live patched" },
> +};
> +
> +unsigned long igt_read_kernel_taint(void)

One thing I haven't checked is whether we can clear the kernel taints.
At the moment, once we see an oops, we never report a second test
generating another oops.
-Chris