[Intel-gfx] [PATCH i-g-t 7/7] test/i915: Add i915_rc6_ctx_corruption

[Chris Wilson]

Quoting Mika Kuoppala (2019-11-13 15:49:13)
> From: Imre Deak <imre.deak at intel.com>
> 
> Add a test to exercise the kernel's mechanism to detection of RC6
> context corruptions, take the necessary action in response (disable
> RC6 and runtime PM) and recover when possible (after system
> suspend/resume).
> 
> v2:
> - Skip test on non-existing engines.
> - Fix for old kernels where the command parser returned EINVAL
>   instead of EACCESS for a banned privilidged command.
> 
> Signed-off-by: Imre Deak <imre.deak at intel.com>
> ---
>  tests/Makefile.sources               |   3 +
>  tests/i915/i915_rc6_ctx_corruption.c | 196 +++++++++++++++++++++++++++
>  tests/meson.build                    |   1 +
>  3 files changed, 200 insertions(+)
>  create mode 100644 tests/i915/i915_rc6_ctx_corruption.c
> 
> diff --git a/tests/Makefile.sources b/tests/Makefile.sources
> index 75c79edb..c0f401c7 100644
> --- a/tests/Makefile.sources
> +++ b/tests/Makefile.sources
> @@ -529,6 +529,9 @@ i915_pm_sseu_SOURCES = i915/i915_pm_sseu.c
>  TESTS_progs += i915_query
>  i915_query_SOURCES = i915/i915_query.c
>  
> +TESTS_progs += i915_rc6_ctx_corruption
> +i915_rc6_ctx_corruption_SOURCES = i915/i915_rc6_ctx_corruption.c
> +
>  TESTS_progs += i915_selftest
>  i915_selftest_SOURCES = i915/i915_selftest.c
>  
> diff --git a/tests/i915/i915_rc6_ctx_corruption.c b/tests/i915/i915_rc6_ctx_corruption.c
> new file mode 100644
> index 00000000..a3326307
> --- /dev/null
> +++ b/tests/i915/i915_rc6_ctx_corruption.c
> @@ -0,0 +1,196 @@
> +/*
> + * Copyright © 2019 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 <stdint.h>
> +
> +#include "igt.h"
> +#include "igt_gt.h"
> +#include "igt_device.h"
> +
> +#define CTX_INFO_REG                   0xA300
> +
> +static int drm_fd;
> +static struct pci_device *pci_dev;
> +static uint32_t devid;
> +
> +static int read_reg_on_engine(const struct intel_execution_engine2 *engine,
> +                             int reg_address, uint32_t *reg_val)
> +{
> +       const bool r64b = intel_gen(devid) >= 8;
> +       struct drm_i915_gem_exec_object2 obj[2];
> +       struct drm_i915_gem_relocation_entry reloc[1];
> +       struct drm_i915_gem_execbuffer2 execbuf;
> +       uint32_t *batch;
> +       uint32_t *dst_buf;
> +       int ret;
> +       int i;
> +
> +       memset(obj, 0, sizeof(obj));
> +       obj[0].handle = gem_create(drm_fd, 4096);
> +       obj[1].handle = gem_create(drm_fd, 4096);
> +       obj[1].relocs_ptr = to_user_pointer(reloc);
> +       obj[1].relocation_count = 1;
> +
> +       batch = gem_mmap__cpu(drm_fd, obj[1].handle, 0, 4096, PROT_WRITE);
> +       gem_set_domain(drm_fd, obj[1].handle,
> +                      I915_GEM_DOMAIN_CPU, I915_GEM_DOMAIN_CPU);
> +
> +       i = 0;
> +       batch[i++] = 0x24 << 23 | (1 + r64b); /* SRM */
> +       batch[i++] = reg_address;
> +       reloc[0].target_handle = obj[0].handle;
> +       reloc[0].presumed_offset = obj[0].offset;
> +       reloc[0].offset = i * sizeof(uint32_t);
> +       reloc[0].delta = 0;
> +       reloc[0].read_domains = I915_GEM_DOMAIN_RENDER;
> +       reloc[0].write_domain = I915_GEM_DOMAIN_RENDER;
> +       batch[i++] = reloc[0].delta;
> +       if (r64b)
> +               batch[i++] = 0;
> +
> +       batch[i++] = MI_BATCH_BUFFER_END;
> +       munmap(batch, 4096);
> +
> +       memset(&execbuf, 0, sizeof(execbuf));
> +       execbuf.buffers_ptr = to_user_pointer(obj);
> +       execbuf.buffer_count = 2;
> +       execbuf.flags = engine->flags;
> +
> +       ret = __gem_execbuf(drm_fd, &execbuf);
> +       gem_close(drm_fd, obj[1].handle);
> +
> +       if (ret)
> +               goto err;
> +
> +       if (reg_val) {
> +               dst_buf = gem_mmap__cpu(drm_fd, obj[0].handle, 0, 4096,
> +                                       PROT_READ);
> +               gem_set_domain(drm_fd, obj[0].handle, I915_GEM_DOMAIN_CPU, 0);
> +
> +               *reg_val = dst_buf[0];
> +               munmap(dst_buf, 4096);
> +       }
> +
> +err:
> +       gem_close(drm_fd, obj[0].handle);
> +
> +       return ret;
> +}
> +
> +static bool need_ctx_corruption_wa(void)
> +{
> +       return IS_BROADWELL(devid) || intel_gen(devid) == 9;

That's a little self servicing and doesn't help find bugs where you
weren't expecting. The test would seem to be useless at predicting new
failures.

This should just be a selftest imo.
-Chris