Updated to work as 2.5.44.

arch/um/Makefile

 ARCH_DIR = arch/um
 OS := $(shell uname -s)
 
-EXTRAVERSION := $(EXTRAVERSION)-3um
+EXTRAVERSION := $(EXTRAVERSION)-1um
 include/linux/version.h: arch/$(ARCH)/Makefile
 
 # Recalculate MODLIB to reflect the EXTRAVERSION changes (via KERNELRELEASE)

arch/um/kernel/ksyms.c

@@ -3,6 +3,7 @@
 #include "linux/string.h"
 #include "linux/smp_lock.h"
 #include "linux/spinlock.h"
+#include <linux/highmem.h>
 #include "asm/current.h"
 #include "asm/delay.h"
 #include "asm/processor.h"
@@ -74,6 +75,13 @@ EXPORT_SYMBOL_NOVERS(__write_lock_failed);
 extern void FASTCALL( __read_lock_failed(rwlock_t *rw));
 EXPORT_SYMBOL_NOVERS(__read_lock_failed);
 
-EXPORT_SYMBOL(smp_num_cpus);
+#endif
 
+#ifdef CONFIG_HIGHMEM
+EXPORT_SYMBOL(kmap);
+EXPORT_SYMBOL(kunmap);
+EXPORT_SYMBOL(kmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic);
+EXPORT_SYMBOL(kmap_atomic_to_page);
 #endif
+

arch/um/kernel/process_kern.c

@@ -767,8 +767,8 @@ void set_thread_sc(void *sc)
 
 int smp_sigio_handler(void)
 {
-	int cpu = current->thread_info->cpu;
 #ifdef CONFIG_SMP
+	int cpu = current->thread_info->cpu;
 	IPI_handler(cpu);
 	if(cpu != 0)
 		return(1);

arch/um/sys-i386/Makefile

-obj-y = bugs.o checksum.o extable.o fault.o ksyms.o ldt.o old-checksum.o \
+obj-y = bugs.o checksum.o extable.o fault.o ksyms.o ldt.o \
 	ptrace.o ptrace_user.o semaphore.o sigcontext.o syscalls.o sysrq.o
 
+obj-$(CONFIG_HIGHMEM) += highmem.o
+
 export-objs = ksyms.o
 
 USER_OBJS := bugs.o ptrace_user.o sigcontext.o fault.o
 USER_OBJS := $(foreach file,$(USER_OBJS),arch/um/sys-i386/$(file))
 
-SYMLINKS = semaphore.c old-checksum.c checksum.S extable.c
+SYMLINKS = semaphore.c checksum.S extable.c highmem.c
 
 include $(TOPDIR)/Rules.make
 
 $(USER_OBJS) : %.o: %.c
 	$(CC) $(CFLAGS_$@) $(USER_CFLAGS) -c -o $@ $<
 
-arch/um/sys-i386/checksum.S arch/um/sys-i386/old-checksum.c: 
+arch/um/sys-i386/checksum.S: 
 	-rm -f $@
 	-ln -s $(TOPDIR)/arch/i386/lib/$(notdir $@) $@
 
@@ -25,6 +27,9 @@ arch/um/sys-i386/extable.c:
 	-rm -f $@
 	-ln -s $(TOPDIR)/arch/i386/mm/$(notdir $@) $@
 
+arch/um/sys-i386/highmem.c:
+	-rm -f $@
+	-ln -s $(TOPDIR)/arch/i386/mm/$(notdir $@) $@
 clean:
 	$(MAKE) -C util clean
 

arch/um/uml.lds.S

@@ -65,7 +65,7 @@ SECTIONS
   .uml.postsetup.init : { *(.uml.postsetup.init) }
   __uml_postsetup_end = .;
   __setup_start = .;
-  .setup.init : { *(.setup.init) }
+  .init.setup : { *(.init.setup) }
   __setup_end = .;
   __per_cpu_start = . ; 
   .data.percpu : { *(.data.percpu) }