Re: [PATCH v4 2/5] tools/lib/mm: add shared file helpers

[Sarthak Sharma <sarthak.sharma@arm.com>]

On 5/27/26 7:54 PM, Sarthak Sharma wrote:
> Move read_file(), write_file(), read_num(), and write_num() out of
> tools/testing/selftests/mm/vm_util.c into a new shared helper under
> tools/lib/mm/.
> 
> These helpers are used by mm selftests today and will also be needed by
> shared hugepage helpers in subsequent patches. Move them to a generic
> location so they can be reused outside selftests as well.
> 
> Keep the helpers exposed to mm selftests through vm_util.h by including
> the new shared header there, and link the new helper into the
> selftests/mm build.
> 
> Add tools/lib/mm/ to the MEMORY MANAGEMENT - MISC entry in MAINTAINERS.
> 
> Signed-off-by: Sarthak Sharma <sarthak.sharma@arm.com>
> ---

Hi Andrew!

Can you please fold the below fixlet into patch 2, as suggested by
Sashiko.

This moves the x86 Makefile prerequisite path fix earlier in the series,
so patch 2 remains buildable on its own. The same hunk is already
present in patch 3 of v4, so if this is folded into patch 2, the
duplicate hunk and the corresponding commit message sentence should be
dropped from patch 3.

If a larger respin is needed after reviewer feedback, I will fold this
into patch 2 in v5 myself.

---
From 1ce0654749f17ae55d7fefefe86bbc55eb3c06d5 Mon Sep 17 00:00:00 2001
From: Sarthak Sharma <sarthak.sharma@arm.com>
Date: Mon, 1 Jun 2026 05:03:53 +0000
Subject: [PATCH v4 fix] selftests/mm: preserve prerequisite paths in x86
build rules

Patch 2 adds tools/lib/mm/file_utils.c as a prerequisite using its full
path. The explicit x86 protection_keys build rules still use $(notdir
$^), which strips that path and makes the compiler look for file_utils.c
in tools/testing/selftests/mm/.

Use $^ instead so pathful prerequisites are preserved.

This fixes the patch 2 bisectability issue reported by Sashiko. The same
hunk is already present in patch 3 of v4. If this is folded into patch
2, that duplicate hunk should be dropped from patch 3.

Signed-off-by: Sarthak Sharma <sarthak.sharma@arm.com>
---
 tools/testing/selftests/mm/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/mm/Makefile
b/tools/testing/selftests/mm/Makefile
index b5fb4b6ab31b..4254200d1cef 100644
--- a/tools/testing/selftests/mm/Makefile
+++ b/tools/testing/selftests/mm/Makefile
@@ -217,7 +217,7 @@ $(BINARIES_32): CFLAGS += -m32 -mxsave
 $(BINARIES_32): LDLIBS += -lrt -ldl -lm
 $(BINARIES_32): $(OUTPUT)/%_32: %.c
 	$(call msg,CC,,$@)
-	$(Q)$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(notdir $^) $(LDLIBS) -o $@
+	$(Q)$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $^ $(LDLIBS) -o $@
 $(foreach t,$(VMTARGETS),$(eval $(call gen-target-rule-32,$(t))))
 endif

@@ -226,7 +226,7 @@ $(BINARIES_64): CFLAGS += -m64 -mxsave
 $(BINARIES_64): LDLIBS += -lrt -ldl
 $(BINARIES_64): $(OUTPUT)/%_64: %.c
 	$(call msg,CC,,$@)
-	$(Q)$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(notdir $^) $(LDLIBS) -o $@
+	$(Q)$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $^ $(LDLIBS) -o $@
 $(foreach t,$(VMTARGETS),$(eval $(call gen-target-rule-64,$(t))))
 endif

--
2.39.5