current_thread_info_reg undefined

current_thread_info_reg undefined

[Meelis Roos]

Todays 2.6.13-rc6+git tree has broken many modules with warning like 
this on sparc64:
*** Warning: "current_thread_info_reg" [drivers/net/ppp_deflate.ko] undefined!

These warnings don't go away after make clean.

-- 
Meelis Roos (mroos@linux.ee)

Re: current_thread_info_reg undefined

[David S. Miller]

From: Meelis Roos <mroos@linux.ee>
Date: Thu, 18 Aug 2005 14:50:31 +0300 (EEST)

> Todays 2.6.13-rc6+git tree has broken many modules with warning like 
> this on sparc64:
> *** Warning: "current_thread_info_reg" [drivers/net/ppp_deflate.ko] undefined!
> 
> These warnings don't go away after make clean.

What does the compiler spit out when drivers/net/ppp_deflate.o
is being built?

It is declared in include/asm-sparc64/thread_info.h quite plainly:

register struct thread_info *current_thread_info_reg asm("g6");

I've seen this before, but I have no idea why it keeps coming up
or what causes it as I've never triggered it myself.

Perhaps it's toolchain dependent, thus some binutils or gcc
bug.

Re: current_thread_info_reg undefined

[Meelis Roos]

> What does the compiler spit out when drivers/net/ppp_deflate.o
> is being built?

I removed the file and reran make. gcc does not say anything and the 
later warning stay.

The warnings are actually longer (were before too):
*** Warning: "" [drivers/net/ppp_deflate.ko] undefined!
*** Warning: "" [drivers/net/ppp_deflate.ko] undefined!
*** Warning: "" [drivers/net/ppp_deflate.ko] undefined!
*** Warning: "current_thread_info_reg" [drivers/net/ppp_deflate.ko] undefined!

make V=1 just shows
   gcc -Wp,-MD,drivers/net/.ppp_deflate.o.d  -nostdinc -isystem 
/usr/lib/gcc/sparc-linux-gnu/4.0.2/include -D__KERNEL__ -Iinclude  -Wall 
-Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common 
-ffreestanding -O2     -fomit-frame-pointer -m64 -pipe -mno-fpu 
-mcpu=ultrasparc -mcmodel=medlow -ffixed-g4 -ffixed-g5 -fcall-used-g7 
-Wno-sign-compare -Wa,--undeclared-regs -finline-limit\x100000 
-Wdeclaration-after-statement -Wno-pointer-sign   -DMODULE 
-DKBUILD_BASENAME=ppp_deflate -DKBUILD_MODNAME=ppp_deflate -c -o 
drivers/net/ppp_deflate.o drivers/net/ppp_deflate.c


> Perhaps it's toolchain dependent, thus some binutils or gcc
> bug.

This host is running up to date Debian unstable so it might easily be 
buggy:

gcc-4.0                4.0.1-4
gcc -v tells it's gcc version 4.0.2 20050806 (prerelease) (Debian 4.0.1-4)

binutils               2.16.1-2
ld -v tells GNU ld version 2.16.1 Debian GNU/Linux

-- 
Meelis Roos (mroos@linux.ee)

Re: current_thread_info_reg undefined

[Ben Collins]

> The warnings are actually longer (were before too):
> *** Warning: "" [drivers/net/ppp_deflate.ko] undefined!
> *** Warning: "" [drivers/net/ppp_deflate.ko] undefined!
> *** Warning: "" [drivers/net/ppp_deflate.ko] undefined!
> *** Warning: "current_thread_info_reg" [drivers/net/ppp_deflate.ko] undefined!

The empty symbol warnings atleast are just a bug with
scripts/mod/modpost.c (the patch fabbione sent you awhile back Dave, for
STT_SPARC_REGISTER changes in glibc's elf.h).

I think the current_thread_info_reg went away with that patch aswell. If
it didn't, I have a fix for that one aswell.

-- 
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Re: current_thread_info_reg undefined

[Meelis Roos]

> The empty symbol warnings atleast are just a bug with
> scripts/mod/modpost.c (the patch fabbione sent you awhile back Dave, for
> STT_SPARC_REGISTER changes in glibc's elf.h).

Yes, the modules in question (at least some I tried) load fine.

-- 
Meelis Roos (mroos@linux.ee)

Re: current_thread_info_reg undefined

[Ben Collins]

On Fri, Aug 19, 2005 at 12:27:39PM -0700, David S. Miller wrote:
> From: Ben Collins <bcollins@debian.org>
> Date: Fri, 19 Aug 2005 04:31:29 -0700
> 
> > The empty symbol warnings atleast are just a bug with
> > scripts/mod/modpost.c (the patch fabbione sent you awhile back Dave, for
> > STT_SPARC_REGISTER changes in glibc's elf.h).
> > 
> > I think the current_thread_info_reg went away with that patch aswell. If
> > it didn't, I have a fix for that one aswell.
> 
> That fix should be in current 2.6.x... Oh I see, it's still checking
> just STT_REGISTER.  Ben, can you resend that patch to me?


--- linux/scripts/mod/modpost.c	2005-06-17 21:48:29.000000000 +0200
+++ linux-source-2.6.12-2.6.12/scripts/mod/modpost.c	2005-06-30 09:29:54.000000000 +0200
@@ -359,11 +359,16 @@
 		/* ignore __this_module, it will be resolved shortly */
 		if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") = 0)
 			break;
-#ifdef STT_REGISTER
+/* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
+#if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
+/* add compatibility with older glibc */
+#ifndef STT_SPARC_REGISTER
+#define STT_SPARC_REGISTER STT_REGISTER
+#endif
 		if (info->hdr->e_machine = EM_SPARC ||
 		    info->hdr->e_machine = EM_SPARCV9) {
 			/* Ignore register directives. */
-			if (ELF_ST_TYPE(sym->st_info) = STT_REGISTER)
+			if (ELF_ST_TYPE(sym->st_info) = STT_SPARC_REGISTER)
 				break;
 		}
 #endif

-- 
Ubuntu     - http://www.ubuntu.com/
Debian     - http://www.debian.org/
Linux 1394 - http://www.linux1394.org/
SwissDisk  - http://www.swissdisk.com/

Re: current_thread_info_reg undefined

[David S. Miller]

From: Ben Collins <bcollins@debian.org>
Date: Fri, 19 Aug 2005 04:31:29 -0700

> The empty symbol warnings atleast are just a bug with
> scripts/mod/modpost.c (the patch fabbione sent you awhile back Dave, for
> STT_SPARC_REGISTER changes in glibc's elf.h).
> 
> I think the current_thread_info_reg went away with that patch aswell. If
> it didn't, I have a fix for that one aswell.

That fix should be in current 2.6.x... Oh I see, it's still checking
just STT_REGISTER.  Ben, can you resend that patch to me?

Re: current_thread_info_reg undefined

[David S. Miller]

Thanks a lot Ben, I'll push this off to Linus.