Re: [PATCH] Shared crc32 for 2.4.

[David Woodhouse]

On Thu, 2003-05-22 at 22:11, David Woodhouse wrote:
> On Thu, 2003-05-22 at 00:50, J.A. Magallon wrote:
> > This works if crc32.o is compiled as a module, but does not work if it is
> > built into the kernel. For example, crc32_le symbol does not appear
> > in System.map nor vmlinux.
> 
> Oh bollocks; sorry I'd forgotten about that.
> 
> Added to the tree from which Marcelo will pull for 2.4.22-pre1...

I hereby declare myself to be Today's Official Mr Fuck All Good.

On top of that patch which fixes CONFIG_CRC32=y, you'll need this patch
which fixes CONFIG_CRC32=m, newly broken (at least with new modutils) by
the removal of the EXPORT_SYMBOL()s from crc32.o...·

Full patch against 2.4.21-rc3 is in
	ftp://ftp.??.kernel.org/pub/linux/kernel/people/dwmw2/crc32/

(and in master.kernel.org:~dwmw2/BK/crc32-2.4 still)

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher.
# This patch includes the following deltas:
#	           ChangeSet	1.1216  -> 1.1217 
#	         lib/crc32.c	1.2     -> 1.3    
#	        lib/Makefile	1.11    -> 1.12   
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/05/23	[e-mail]	1.1217
# Fix CONFIG_CRC32=m by make crc32.o export its own symbols again in that case.
# --------------------------------------------
#
diff -Nru a/lib/Makefile b/lib/Makefile
--- a/lib/Makefile	Fri May 23 10:09:17 2003
+++ b/lib/Makefile	Fri May 23 10:09:17 2003
@@ -8,7 +8,8 @@
 
 L_TARGET := lib.a
 
-export-objs := cmdline.o dec_and_lock.o rwsem-spinlock.o rwsem.o rbtree.o
+export-objs := cmdline.o dec_and_lock.o rwsem-spinlock.o rwsem.o \
+	       rbtree.o crc32.o
 
 obj-y := errno.o ctype.o string.o vsprintf.o brlock.o cmdline.o \
 	 bust_spinlocks.o rbtree.o dump_stack.o
diff -Nru a/lib/crc32.c b/lib/crc32.c
--- a/lib/crc32.c	Fri May 23 10:09:17 2003
+++ b/lib/crc32.c	Fri May 23 10:09:17 2003
@@ -266,6 +266,13 @@
 	return x;
 }
 
+#ifdef MODULE /* These are exported from kernel/ksyms.c in the non-module
+		 case, to ensure that this file is pulled in from lib/lib.a */
+EXPORT_SYMBOL(crc32_le);
+EXPORT_SYMBOL(crc32_be);
+EXPORT_SYMBOL(bitreverse);
+#endif
+
 /*
  * A brief CRC tutorial.
  *

-- 
dwmw2