Bugs in mini-os on i386 architecture

Bugs in mini-os on i386 architecture

[Melvin Anderson]

I have been trying to get mini-os to run on i386 architecture, 
(xen-unstable.hg, 9325:1ecb7f1ddc79) but have hit problems:

-- header file extras/mini-os/include/console.h is missing,

-- type mismatch in extras/mini-os/xenbus/xenbus_xs.c causes compile 
   to fail, and

-- page fault occurs in extras/mini-os/mm.c because page directory table 
   entries are set up incorrectly.  The array mmu_updates in new_pt_frame() 
   has zero entries, but should have at least 1 entry.

I wonder if whoever is actively working on mini-os could review these 
patches, and merge them in to the sources.  The header file console.h 
contains the minimum amount needed to get mini-os to compile -- the 
writer of console.c may have intended it to contain more.

Regards,

Melvin Anderson.

diff -r 1ecb7f1ddc79 extras/mini-os/mm.c
--- a/extras/mini-os/mm.c	Sun Mar 19 17:55:46 2006
+++ b/extras/mini-os/mm.c	Mon Mar 20 14:28:01 2006
@@ -373,7 +373,7 @@
     unsigned long *tab = (unsigned long *)start_info.pt_base;
     unsigned long pt_page = (unsigned long)pfn_to_virt(*pt_pfn); 
     unsigned long prot_e, prot_t, pincmd;
-    mmu_update_t mmu_updates[0];
+    mmu_update_t mmu_updates[1];
     struct mmuext_op pin_request;
     
     DEBUG("Allocating new L%d pt frame for pt_pfn=%lx, "
diff -r 1ecb7f1ddc79 extras/mini-os/xenbus/xenbus_xs.c
--- a/extras/mini-os/xenbus/xenbus_xs.c	Sun Mar 19 17:55:46 2006
+++ b/extras/mini-os/xenbus/xenbus_xs.c	Mon Mar 20 14:28:01 2006
@@ -335,7 +335,7 @@
 		  const char *dir, const char *node)
 {
 	char **d;
-	int dir_n;
+	unsigned int dir_n;
 
 	d = xenbus_directory(t, dir, node, &dir_n);
 	if (IS_ERR(d))
diff -r 1ecb7f1ddc79 extras/mini-os/include/console.h
--- /dev/null	Sun Mar 19 17:55:46 2006
+++ b/extras/mini-os/include/console.h	Mon Mar 20 14:28:01 2006
@@ -0,0 +1,15 @@
+/* -*-  Mode:C; c-basic-offset:4; tab-width:4 -*- */
+
+#ifndef _CONSOLE_H_
+#define _CONSOLE_H_
+
+#include <stdarg.h>
+#include <traps.h>
+
+void printk(const char *fmt, ...);
+void xencons_rx(char *, unsigned, struct pt_regs *);
+void xencons_tx(void);
+
+
+
+#endif /* _CONSOLE_H_ */

--

Melvin Anderson, Trusted Systems Laboratory, HPLabs, Bristol.

Re: Bugs in mini-os on i386 architecture

[Grzegorz Milos]

> I have been trying to get mini-os to run on i386 architecture, 
> (xen-unstable.hg, 9325:1ecb7f1ddc79) but have hit problems:
> 
> -- header file extras/mini-os/include/console.h is missing,

A patch has just been sent out to the list. Thanks for pointing that out.

> -- type mismatch in extras/mini-os/xenbus/xenbus_xs.c causes compile 
>    to fail, and

XenBus implementation got replaced with a new one by Steven Smith. This 
should therefore not be an issue any more.

> -- page fault occurs in extras/mini-os/mm.c because page directory table 
>    entries are set up incorrectly.  The array mmu_updates in new_pt_frame() 
>    has zero entries, but should have at least 1 entry.

The last patch fixes that as well.

> I wonder if whoever is actively working on mini-os could review these 
> patches, and merge them in to the sources.  The header file console.h 
> contains the minimum amount needed to get mini-os to compile -- the 
> writer of console.c may have intended it to contain more.

What you've put there is almost everything (only relevant change was 
addition of the license).

Thanks for help Malvin!

Cheers
Gregor

RE: Bugs in mini-os on i386 architecture

[Puthiyaparambil, Aravindh]

I am finding the same issues with x86_64 too. So I think this patch
needs to go in. 

Gregor, do you agree? I am also found that minios i386 and x86_64, now
does not complete console_init() with the latest changeset
9364:22f1618cf57c. Any idea why this is happening? 

Cheers,
Aravindh

xenbox:~/xen/xen-unstable/extras/mini-os # xm create -c domain_config 
Using config file "domain_config".
Started domain Mini-OS
xenconsole: Could not read tty from store: No such file or directory
Bootstrapping...
Xen Minimal OS!
start_info:   ffffffff00028000
  nr_pages:   8192  shared_inf: 00faf000
  pt_base:    ffffffff0002b000  mod_start:  0x0
  mod_len:    0
  flags:      0x0
  cmd_line:   
MM: Init
  _text:        ffffffff00000000
  _etext:       ffffffff0000c67a
  _edata:       ffffffff0000de78
  stack start:  ffffffff00014be0
  _end:         ffffffff00017088
  start_pfn:    33
  max_pfn:      2000
Mapping memory range 0xffffffff00400000 - 0xffffffff02000000
MM: Initialise page allocator for
ffffffff00041000(41000)-ffffffff02000000(2000000)
MM: done
Initialising timer interface
Initialising console ...



> -----Original Message-----
> From: xen-devel-bounces@lists.xensource.com [mailto:xen-devel-
> bounces@lists.xensource.com] On Behalf Of Melvin Anderson
> Sent: Monday, March 20, 2006 10:18 AM
> To: xen-devel@lists.xensource.com
> Subject: [Xen-devel] Bugs in mini-os on i386 architecture
> 
> I have been trying to get mini-os to run on i386 architecture,
> (xen-unstable.hg, 9325:1ecb7f1ddc79) but have hit problems:
> 
> -- header file extras/mini-os/include/console.h is missing,
> 
> -- type mismatch in extras/mini-os/xenbus/xenbus_xs.c causes compile
>    to fail, and
> 
> -- page fault occurs in extras/mini-os/mm.c because page directory
table
>    entries are set up incorrectly.  The array mmu_updates in
> new_pt_frame()
>    has zero entries, but should have at least 1 entry.
> 

Re: Bugs in mini-os on i386 architecture

[Grzegorz Milos]

This is not a bug (it's a feature :) ).

As soon as console is initialised the output is no longer printed to the 
emergency console. It is available through the usual: xm console <dom_name>.
If you want to print something to the emergency console use newly 
defined function: xprintk.

Cheers
Gregor


> I am finding the same issues with x86_64 too. So I think this patch
> needs to go in. 
> 
> Gregor, do you agree? I am also found that minios i386 and x86_64, now
> does not complete console_init() with the latest changeset
> 9364:22f1618cf57c. Any idea why this is happening? 
> 
> Cheers,
> Aravindh
> 
> xenbox:~/xen/xen-unstable/extras/mini-os # xm create -c domain_config 
> Using config file "domain_config".
> Started domain Mini-OS
> xenconsole: Could not read tty from store: No such file or directory
> Bootstrapping...
> Xen Minimal OS!
> start_info:   ffffffff00028000
>   nr_pages:   8192  shared_inf: 00faf000
>   pt_base:    ffffffff0002b000  mod_start:  0x0
>   mod_len:    0
>   flags:      0x0
>   cmd_line:   
> MM: Init
>   _text:        ffffffff00000000
>   _etext:       ffffffff0000c67a
>   _edata:       ffffffff0000de78
>   stack start:  ffffffff00014be0
>   _end:         ffffffff00017088
>   start_pfn:    33
>   max_pfn:      2000
> Mapping memory range 0xffffffff00400000 - 0xffffffff02000000
> MM: Initialise page allocator for
> ffffffff00041000(41000)-ffffffff02000000(2000000)
> MM: done
> Initialising timer interface
> Initialising console ...
> 
> 
> 
>> -----Original Message-----
>> From: xen-devel-bounces@lists.xensource.com [mailto:xen-devel-
>> bounces@lists.xensource.com] On Behalf Of Melvin Anderson
>> Sent: Monday, March 20, 2006 10:18 AM
>> To: xen-devel@lists.xensource.com
>> Subject: [Xen-devel] Bugs in mini-os on i386 architecture
>>
>> I have been trying to get mini-os to run on i386 architecture,
>> (xen-unstable.hg, 9325:1ecb7f1ddc79) but have hit problems:
>>
>> -- header file extras/mini-os/include/console.h is missing,
>>
>> -- type mismatch in extras/mini-os/xenbus/xenbus_xs.c causes compile
>>    to fail, and
>>
>> -- page fault occurs in extras/mini-os/mm.c because page directory
> table
>>    entries are set up incorrectly.  The array mmu_updates in
>> new_pt_frame()
>>    has zero entries, but should have at least 1 entry.
>>