diff -up ./samples/bpf/Makefile.t4 ./samples/bpf/Makefile
--- ./samples/bpf/Makefile.t4	2026-02-01 08:09:53.000000000 +0900
+++ ./samples/bpf/Makefile	2026-05-28 20:16:52.227141384 +0900
@@ -219,6 +219,10 @@ endif
 endif
 endif
 
+ifeq ($(ARCH),i386)
+	BPF_EXTRA_CFLAGS += -D_TIME_BITS=64 -D_FILE_OFFSET_BITS=64
+endif
+
 # Trick to allow make to be run from this directory
 all:
 	$(MAKE) -C ../../ M=$(CURDIR) BPF_SAMPLES_PATH=$(CURDIR)
diff -up ./tools/bpf/Makefile.t4 ./tools/bpf/Makefile
--- ./tools/bpf/Makefile.t4	2026-02-01 08:09:53.000000000 +0900
+++ ./tools/bpf/Makefile	2026-05-28 20:16:52.242141408 +0900
@@ -12,6 +12,8 @@ CFLAGS += -Wall -O2
 CFLAGS += -D__EXPORTED_HEADERS__ -I$(srctree)/tools/include/uapi \
 	  -I$(srctree)/tools/include
 
+CFLAGS += -D_TIME_BITS=64 -D_FILE_OFFSET_BITS=64
+
 # This will work when bpf is built in tools env. where srctree
 # isn't set and when invoked from selftests build, where srctree
 # is set to ".". building_out_of_srctree is undefined for in srctree
diff -up ./tools/bpf/bpftool/Makefile.t4 ./tools/bpf/bpftool/Makefile
--- ./tools/bpf/bpftool/Makefile.t4	2026-02-01 08:09:53.000000000 +0900
+++ ./tools/bpf/bpftool/Makefile	2026-05-28 20:16:52.253141426 +0900
@@ -73,6 +73,7 @@ CFLAGS += -DPACKAGE='"bpftool"' -D__EXPO
 	-I$(srctree)/kernel/bpf/ \
 	-I$(srctree)/tools/include \
 	-I$(srctree)/tools/include/uapi
+CFLAGS += -D_TIME_BITS=64 -D_FILE_OFFSET_BITS=64
 ifneq ($(BPFTOOL_VERSION),)
 CFLAGS += -DBPFTOOL_VERSION='"$(BPFTOOL_VERSION)"'
 endif
diff -up ./tools/lib/api/Makefile.t4 ./tools/lib/api/Makefile
--- ./tools/lib/api/Makefile.t4	2026-02-01 08:09:53.000000000 +0900
+++ ./tools/lib/api/Makefile	2026-05-28 20:16:52.265141445 +0900
@@ -46,6 +46,7 @@ endif
 CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
 CFLAGS += -I$(srctree)/tools/lib/api
 CFLAGS += -I$(srctree)/tools/include
+CFLAGS += -D_TIME_BITS=64
 
 RM = rm -f
 
diff -up ./tools/lib/bpf/Makefile.t4 ./tools/lib/bpf/Makefile
--- ./tools/lib/bpf/Makefile.t4	2026-02-01 08:09:53.000000000 +0900
+++ ./tools/lib/bpf/Makefile	2026-05-28 20:16:52.272141457 +0900
@@ -85,6 +85,9 @@ override CFLAGS += $(INCLUDES)
 override CFLAGS += -fvisibility=hidden
 override CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
 override CFLAGS += $(CLANG_CROSS_FLAGS)
+#ifeq ($(ARCH),i386)
+override CFLAGS += -D_TIME_BITS=64
+#endif
 
 # flags specific for shared library
 SHLIB_FLAGS := -DSHARED -fPIC
diff -up ./tools/lib/subcmd/Makefile.t4 ./tools/lib/subcmd/Makefile
--- ./tools/lib/subcmd/Makefile.t4	2026-02-01 08:09:53.000000000 +0900
+++ ./tools/lib/subcmd/Makefile	2026-05-28 20:16:52.282141473 +0900
@@ -48,6 +48,7 @@ ifneq ($(WERROR),0)
 endif
 
 CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE
+CFLAGS += -D_TIME_BITS=64
 
 CFLAGS += -I$(srctree)/tools/include/
 
diff -up ./tools/lib/symbol/Makefile.t4 ./tools/lib/symbol/Makefile
--- ./tools/lib/symbol/Makefile.t4	2026-02-01 08:09:53.000000000 +0900
+++ ./tools/lib/symbol/Makefile	2026-05-28 20:16:52.300141502 +0900
@@ -44,6 +44,7 @@ ifneq ($(WERROR),0)
 endif
 
 CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
+CFLAGS += -D_TIME_BITS=64
 
 CFLAGS += -I$(srctree)/tools/lib
 CFLAGS += -I$(srctree)/tools/include
diff -up ./tools/perf/Makefile.config.t4 ./tools/perf/Makefile.config
--- ./tools/perf/Makefile.config.t4	2026-02-01 08:09:53.000000000 +0900
+++ ./tools/perf/Makefile.config	2026-05-28 20:16:52.319141532 +0900
@@ -386,6 +386,7 @@ INC_FLAGS += -I$(src-perf)/util
 INC_FLAGS += -I$(src-perf)
 
 CORE_CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE
+CORE_CFLAGS += -D_TIME_BITS=64
 
 CFLAGS   += $(CORE_CFLAGS) $(INC_FLAGS)
 CXXFLAGS += $(INC_FLAGS)
diff -up ./tools/testing/selftests/bpf/Makefile.t4 ./tools/testing/selftests/bpf/Makefile
--- ./tools/testing/selftests/bpf/Makefile.t4	2026-02-01 08:09:53.000000000 +0900
+++ ./tools/testing/selftests/bpf/Makefile	2026-05-28 20:16:52.332141553 +0900
@@ -61,6 +61,10 @@ ifneq ($(LLVM),)
 # Silence some warnings when compiled with clang
 CFLAGS += -Wno-unused-command-line-argument
 endif
+# y2038 on 32bit
+##ifeq ($(ARCH),i386)
+CFLAGS += -D_TIME_BITS=64 -D_FILE_OFFSET_BITS=64
+##endif
 
 # Check whether bpf cpu=v4 is supported or not by clang
 ifneq ($(shell $(CLANG) --target=bpf -mcpu=help 2>&1 | grep 'v4'),)
@@ -305,6 +309,7 @@ endif
 
 $(OUTPUT)/runqslower: $(BPFOBJ) | $(DEFAULT_BPFTOOL) $(RUNQSLOWER_OUTPUT)
 	$(Q)$(MAKE) $(submake_extras) -C $(TOOLSDIR)/bpf/runqslower	       \
+		    CFLAGS="$(CFLAGS)"                                         \
 		    OUTPUT=$(RUNQSLOWER_OUTPUT) VMLINUX_BTF=$(VMLINUX_BTF)     \
 		    BPFTOOL_OUTPUT=$(HOST_BUILD_DIR)/bpftool/		       \
 		    BPFOBJ_OUTPUT=$(BUILD_DIR)/libbpf/			       \