Several selftests Makefiles (e.g. prctl, breakpoints, etc) attempt to
normalize the ARCH variable by converting x86_64 and i.86 to x86.
However, it uses the conditional assignment operator '?='.

When ARCH is passed as a command-line argument (e.g., during an rpmbuild
process), the '?=' operator ignores the shell command and the sed
transformation. This leads to an incorrect ARCH value being used, which
causes build failures

  # make -C tools/testing/selftests TARGETS=prctl ARCH=x86_64
  make: Entering directory '/build/tools/testing/selftests'
  make[1]: Entering directory '/build/tools/testing/selftests/prctl'
  make[1]: *** No targets.  Stop.
  make[1]: Leaving directory '/build/tools/testing/selftests/prctl'
  make: *** [Makefile:197: all] Error 2

Change the assignment to use 'override' and ':=' to ensure the
normalization logic is applied regardless of how the ARCH variable
was initially defined.

Signed-off-by: Aleksei Oladko <aleksey.oladko@virtuozzo.com>
---
 tools/testing/selftests/breakpoints/Makefile              | 4 ++--
 tools/testing/selftests/ipc/Makefile                      | 8 ++++----
 tools/testing/selftests/prctl/Makefile                    | 4 ++--
 tools/testing/selftests/sparc64/Makefile                  | 4 ++--
 .../testing/selftests/thermal/intel/power_floor/Makefile  | 4 ++--
 .../selftests/thermal/intel/workload_hint/Makefile        | 4 ++--
 6 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/tools/testing/selftests/breakpoints/Makefile b/tools/testing/selftests/breakpoints/Makefile
index 9ec2c78de8ca..0b8f5acf7c78 100644
--- a/tools/testing/selftests/breakpoints/Makefile
+++ b/tools/testing/selftests/breakpoints/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 # Taken from perf makefile
-uname_M := $(shell uname -m 2>/dev/null || echo not)
-ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
+ARCH ?= $(shell uname -m 2>/dev/null || echo not)
+override ARCH := $(shell echo $(ARCH) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
 
 TEST_GEN_PROGS := step_after_suspend_test
 
diff --git a/tools/testing/selftests/ipc/Makefile b/tools/testing/selftests/ipc/Makefile
index 50e9c299fc4a..fad10f2bb57b 100644
--- a/tools/testing/selftests/ipc/Makefile
+++ b/tools/testing/selftests/ipc/Makefile
@@ -1,12 +1,12 @@
 # SPDX-License-Identifier: GPL-2.0
-uname_M := $(shell uname -m 2>/dev/null || echo not)
-ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/)
+ARCH ?= $(shell uname -m 2>/dev/null || echo not)
+override ARCH := $(shell echo $(ARCH) | sed -e s/i.86/i386/)
 ifeq ($(ARCH),i386)
-        ARCH := x86
+        override ARCH := x86
 	CFLAGS := -DCONFIG_X86_32 -D__i386__
 endif
 ifeq ($(ARCH),x86_64)
-	ARCH := x86
+        override ARCH := x86
 	CFLAGS := -DCONFIG_X86_64 -D__x86_64__
 endif
 
diff --git a/tools/testing/selftests/prctl/Makefile b/tools/testing/selftests/prctl/Makefile
index 01dc90fbb509..e770e86fad9a 100644
--- a/tools/testing/selftests/prctl/Makefile
+++ b/tools/testing/selftests/prctl/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 ifndef CROSS_COMPILE
-uname_M := $(shell uname -m 2>/dev/null || echo not)
-ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
+ARCH ?= $(shell uname -m 2>/dev/null || echo not)
+override ARCH := $(shell echo $(ARCH) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
 
 ifeq ($(ARCH),x86)
 TEST_PROGS := disable-tsc-ctxt-sw-stress-test disable-tsc-on-off-stress-test \
diff --git a/tools/testing/selftests/sparc64/Makefile b/tools/testing/selftests/sparc64/Makefile
index a19531dba4dc..88f7be76f962 100644
--- a/tools/testing/selftests/sparc64/Makefile
+++ b/tools/testing/selftests/sparc64/Makefile
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
-uname_M := $(shell uname -m 2>/dev/null || echo not)
-ARCH ?= $(shell echo $(uname_M) | sed -e s/x86_64/x86/)
+ARCH ?= $(shell uname -m 2>/dev/null || echo not)
+override ARCH := $(shell echo $(ARCH) | sed -e s/x86_64/x86/)
 
 ifneq ($(ARCH),sparc64)
 nothing:
diff --git a/tools/testing/selftests/thermal/intel/power_floor/Makefile b/tools/testing/selftests/thermal/intel/power_floor/Makefile
index 9b88e57dbba5..07463c2160e0 100644
--- a/tools/testing/selftests/thermal/intel/power_floor/Makefile
+++ b/tools/testing/selftests/thermal/intel/power_floor/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 ifndef CROSS_COMPILE
-uname_M := $(shell uname -m 2>/dev/null || echo not)
-ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
+ARCH ?= $(shell uname -m 2>/dev/null || echo not)
+override ARCH := $(shell echo $(ARCH) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
 
 ifeq ($(ARCH),x86)
 TEST_GEN_PROGS := power_floor_test
diff --git a/tools/testing/selftests/thermal/intel/workload_hint/Makefile b/tools/testing/selftests/thermal/intel/workload_hint/Makefile
index 37ff3286283b..49e3bc2b20f9 100644
--- a/tools/testing/selftests/thermal/intel/workload_hint/Makefile
+++ b/tools/testing/selftests/thermal/intel/workload_hint/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 ifndef CROSS_COMPILE
-uname_M := $(shell uname -m 2>/dev/null || echo not)
-ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
+ARCH ?= $(shell uname -m 2>/dev/null || echo not)
+override ARCH := $(shell echo $(ARCH) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
 
 ifeq ($(ARCH),x86)
 TEST_GEN_PROGS := workload_hint_test
-- 
2.43.0

On Mon,  9 Mar 2026 20:51:45 +0000 Aleksei Oladko <aleksey.oladko@virtuozzo.com> wrote:

> Several selftests Makefiles (e.g. prctl, breakpoints, etc) attempt to
> normalize the ARCH variable by converting x86_64 and i.86 to x86.
> However, it uses the conditional assignment operator '?='.
> 
> When ARCH is passed as a command-line argument (e.g., during an rpmbuild
> process), the '?=' operator ignores the shell command and the sed
> transformation. This leads to an incorrect ARCH value being used, which
> causes build failures
> 
>   # make -C tools/testing/selftests TARGETS=prctl ARCH=x86_64
>   make: Entering directory '/build/tools/testing/selftests'
>   make[1]: Entering directory '/build/tools/testing/selftests/prctl'
>   make[1]: *** No targets.  Stop.
>   make[1]: Leaving directory '/build/tools/testing/selftests/prctl'
>   make: *** [Makefile:197: all] Error 2
> 
> Change the assignment to use 'override' and ':=' to ensure the
> normalization logic is applied regardless of how the ARCH variable
> was initially defined.

lgtm, thanks.

> --- a/tools/testing/selftests/ipc/Makefile
> +++ b/tools/testing/selftests/ipc/Makefile
> @@ -1,12 +1,12 @@
>  # SPDX-License-Identifier: GPL-2.0
> -uname_M := $(shell uname -m 2>/dev/null || echo not)
> -ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/)
> +ARCH ?= $(shell uname -m 2>/dev/null || echo not)

What does this `echo not' do?  ARCH=not if uname failed?