Compile error: 2.4.15-pre4 (-tr) in kernel.o (cpu_init()) - advice req'd

Compile error: 2.4.15-pre4 (-tr) in kernel.o (cpu_init()) - advice req'd

[Ben Ryan]

hey all

hope this doesn't turn out to be spurious traffic...

ia32/uniproc

linux-2.4.14.tar (kernel tar)
patch-2.4.15-pre4 (merge)
fix-2.4.15-pre4-tr.diff (benlahaise; don't mind the filename, i just
                         reckon calling the patch for the patch,
                         patch-2.4.* is brokenness)


there is some weirdness on the box i'm compiling on; please check the
following for obvious causes...
pre-compile make's worked fine, but the compile itself crashed out
with:

arch/i386/kernel/kernel.o: In function 'cpu_init':
arch/i386/kernel/kernel.o(.text.init+0x27f9): undefined reference to 'cpucount'
arch/i386/kernel/kernel.o(.text.init+0x2831): undefined reference to 'cpucount'


Can anyone spot if it's code or meatware related??
Thanx, I won't be able to sleep till I know what's going on :)

cheers
ben





Segment of kernel.o containing the offender:
================
  * cpu_init() initializes state that is per-CPU. Some data is already
@@ -2815,14 +2817,15 @@
  */
 void __init cpu_init (void)
 {
-       int nr = smp_processor_id();
+       int nr = cpucount;
+       struct task_struct *cur = init_tasks[nr];
        struct tss_struct * t = &init_tss[nr];
 
        if (test_and_set_bit(nr, &cpu_initialized)) {
                printk(KERN_WARNING "CPU#%d already initialized!\n", nr);
                for (;;) __sti();

Uniprocessor Compile error: 2.4.15-pre4 (-tr) in kernel.o (cpu_init()) - Works with SMP

[Ben Ryan]

> linux-2.4.14.tar (kernel tar)
> patch-2.4.15-pre4 (merge)
> fix-2.4.15-pre4-tr.diff (benlahaise; don't mind the filename, i just
>                          reckon calling the patch for the patch,
>                          patch-2.4.* is brokenness)

> arch/i386/kernel/kernel.o: In function 'cpu_init':
> arch/i386/kernel/kernel.o(.text.init+0x27f9): undefined reference to 'cpucount'
> arch/i386/kernel/kernel.o(.text.init+0x2831): undefined reference to 'cpucount'
> Segment of kernel.o containing the offender:
> ================
>   * cpu_init() initializes state that is per-CPU. Some data is already
> @@ -2815,14 +2817,15 @@
>   */
>  void __init cpu_init (void)
>  {
> -       int nr = smp_processor_id();
> +       int nr = cpucount;
> +       struct task_struct *cur = init_tasks[nr];
>         struct tss_struct * t = &init_tss[nr];
 
>         if (test_and_set_bit(nr, &cpu_initialized)) {
>                 printk(KERN_WARNING "CPU#%d already initialized!\n", nr);
>                 for (;;) __sti();


SMP compile succeeded. (albeit with lots of warnings on 'pure')

It seems cpucount is only defined when SMP is compiled in, I guess cpucount
hasn't been set to 1 in uniprocessor build, breaking non-smp builds?
How can I hardcode that into setup.c? I know little of C, so if someone could
point out a line of code to set this (diff even?) :)

Re: Uniprocessor Compile error: 2.4.15-pre4 (-tr) in kernel.o (cpu_init()) - Works with SMP

[Benjamin LaHaise]

On Wed, Nov 14, 2001 at 07:44:59AM +1100, Ben Ryan wrote:
...
> SMP compile succeeded. (albeit with lots of warnings on 'pure')

Which version of gcc?  2.95?  I guess the pure attribute needs to be 
made a compiler.h thing.

> It seems cpucount is only defined when SMP is compiled in, I guess cpucount
> hasn't been set to 1 in uniprocessor build, breaking non-smp builds?
> How can I hardcode that into setup.c? I know little of C, so if someone could
> point out a line of code to set this (diff even?) :)

This will fix the link error by moving cpucount into setup.c.  Cheers,

		-ben


diff -ur tr-2.4.15-pre4/arch/i386/kernel/setup.c tr.prev/arch/i386/kernel/setup.c
--- tr-2.4.15-pre4/arch/i386/kernel/setup.c	Tue Nov 13 16:25:33 2001
+++ tr.prev/arch/i386/kernel/setup.c	Tue Nov 13 15:00:40 2001
@@ -2807,7 +2807,7 @@
 };
 
 unsigned long cpu_initialized __initdata = 0;
-int cpucount;
+extern int cpucount;
 
 /*
  * cpu_init() initializes state that is per-CPU. Some data is already
diff -ur tr-2.4.15-pre4/arch/i386/kernel/smpboot.c tr.prev/arch/i386/kernel/smpboot.c
--- tr-2.4.15-pre4/arch/i386/kernel/smpboot.c	Tue Nov 13 16:25:46 2001
+++ tr.prev/arch/i386/kernel/smpboot.c	Tue Nov 13 15:00:40 2001
@@ -443,7 +443,7 @@
 		synchronize_tsc_ap();
 }
 
-extern int cpucount;
+int cpucount;
 
 extern int cpu_idle(void);
 

Re: Uniprocessor Compile error: 2.4.15-pre4 (-tr) in kernel.o (cpu_init()) - Works with SMP

[Robert Love]

On Tue, 2001-11-13 at 16:28, Benjamin LaHaise wrote:
> This will fix the link error by moving cpucount into setup.c.

Looks like the patch is reversed.  Attached is a reversed version of the
aforementioned reversed patch.

--- linux-2.4.15-pre4/arch/i386/kernel/setup.c	Mon Nov 12 17:39:00 2001
+++ linux/arch/i386/kernel/setup.c	Tue Nov 13 23:08:53 2001
@@ -2806,6 +2807,7 @@
 };
 
 unsigned long cpu_initialized __initdata = 0;
+int cpucount;
 
 /*
  * cpu_init() initializes state that is per-CPU. Some data is already
--- linux-2.4.15-pre4/arch/i386/kernel/smpboot.c	Mon Nov 12 17:39:00 2001
+++ linux/arch/i386/kernel/smpboot.c	Tue Nov 13 23:08:53 2001
@@ -443,7 +443,7 @@
 		synchronize_tsc_ap();
 }
 
-int cpucount;
+extern int cpucount;
 
 extern int cpu_idle(void);
 
	Robert Love

Re: Uniprocessor Compile error: 2.4.15-pre4 (-tr) in kernel.o (cpu_init()) - Works with SMP

[Robert Love]

On Wed, Nov 14, 2001 at 07:44:59AM +1100, Ben Ryan wrote:
> SMP compile succeeded. (albeit with lots of warnings on 'pure')

UP users of the patch will want to apply this, too:

diff -urN rattlesnake/include/asm-i386/current_asm.h  linux/include/asm-i386/current_asm.h 
--- rattlesnake/include/asm-i386/current_asm.h	Thu Nov 15 14:07:46 2001
+++ linux/include/asm-i386/current_asm.h	Thu Nov 15 14:08:15 2001
@@ -7,7 +7,7 @@
 #include <linux/per_cpu.h>
 #include <asm/desc.h>
 
-#if 1 /*def CONFIG_SMP*/
+#ifdef CONFIG_SMP
 /* Pass in the long and short versions of the register.
  * eg GET_CURRENT(%ebx,%bx)
  * All of this braindamage comes to us c/o a bug in gas: the


	Robert Love