Commit 8c149eb0 authored by Dan Williams's avatar Dan Williams
Browse files

tools/testing/cxl: Prevent cxl_test from confusing production modules 

The cxl_test machinery builds modified versions of the modules in
drivers/cxl/ and intercepts some of their calls to allow cxl_test to
inject mock CXL topologies for test.

However, if cxl_test attempts the same with production modules,
fireworks ensue as Luis discovered [1]. Prevent that scenario by
arranging for cxl_test to check for a "watermark" symbol in each of the
modules it expects to be modified before the test can run. This turns
undefined runtime behavior or crashes into a safer failure to load the
cxl_test module.

Link: http://lore.kernel.org/r/20221209062919.1096779-1-mcgrof@kernel.org

 [1]
Reported-by: default avatarLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent e520d52d

tools/testing/cxl/Kbuild

+6 −0
Original line number Diff line number Diff line
@@ -24,22 +24,27 @@ obj-m += cxl_acpi.o 
cxl_acpi-y := $(CXL_SRC)/acpi.o

cxl_acpi-y += mock_acpi.o

cxl_acpi-y += config_check.o

cxl_acpi-y += cxl_acpi_test.o



obj-m += cxl_pmem.o



cxl_pmem-y := $(CXL_SRC)/pmem.o

cxl_pmem-y += $(CXL_SRC)/security.o

cxl_pmem-y += config_check.o

cxl_pmem-y += cxl_pmem_test.o



obj-m += cxl_port.o



cxl_port-y := $(CXL_SRC)/port.o

cxl_port-y += config_check.o

cxl_port-y += cxl_port_test.o





obj-m += cxl_mem.o



cxl_mem-y := $(CXL_SRC)/mem.o

cxl_mem-y += config_check.o

cxl_mem-y += cxl_mem_test.o



obj-m += cxl_core.o
@@ -53,5 +58,6 @@ cxl_core-y += $(CXL_CORE_SRC)/hdm.o 
cxl_core-$(CONFIG_TRACING) += $(CXL_CORE_SRC)/trace.o

cxl_core-$(CONFIG_CXL_REGION) += $(CXL_CORE_SRC)/region.o

cxl_core-y += config_check.o

cxl_core-y += cxl_core_test.o



obj-m += test/

tools/testing/cxl/cxl_acpi_test.c

0 → 100644
+6 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright(c) 2022 Intel Corporation. All rights reserved. */



#include "watermark.h"



cxl_test_watermark(cxl_acpi);

tools/testing/cxl/cxl_core_test.c

0 → 100644
+6 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright(c) 2022 Intel Corporation. All rights reserved. */



#include "watermark.h"



cxl_test_watermark(cxl_core);

tools/testing/cxl/cxl_mem_test.c

0 → 100644
+6 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright(c) 2022 Intel Corporation. All rights reserved. */



#include "watermark.h"



cxl_test_watermark(cxl_mem);

tools/testing/cxl/cxl_pmem_test.c

0 → 100644
+6 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright(c) 2022 Intel Corporation. All rights reserved. */



#include "watermark.h"



cxl_test_watermark(cxl_pmem);