[PATCH] let XEN depend on PAE

[PATCH] let XEN depend on PAE

[Arnd Hannemann]

Hi,

As paravirtualized xen guests won't work with !X86_PAE, change the Kconfig
accordingly.

Signed-off-by: Arnd Hannemann <hannemann@nets.rwth-aachen.de>

diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index 4d5f264..2035238 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -6,7 +6,7 @@ config XEN
    bool "Xen guest support"
    select PARAVIRT
    depends on X86_32
-   depends on X86_CMPXCHG && X86_TSC && !NEED_MULTIPLE_NODES && !(X86_VISWS ||
X86_VOYAGER)
+   depends on X86_PAE && X86_CMPXCHG && X86_TSC && !NEED_MULTIPLE_NODES &&
!(X86_VISWS || X86_VOYAGER)
    help
      This is the Linux Xen port.  Enabling this will allow the
      kernel to boot in a paravirtualized environment under the

Re: [PATCH] let XEN depend on PAE

[Ian Campbell]

On Fri, 2008-02-22 at 12:00 +0100, Arnd Hannemann wrote:
> As paravirtualized xen guests won't work with !X86_PAE, change the Kconfig
> accordingly.

Really? Xen guests should work on non-PAE if you have a non-PAE
hypervisor (which most distros don't ship but which does exist).

Ian.

-- 
Ian Campbell
Current Noise: The Ocean - Mesoproterozoic - Calymmian - Lake Disappointment

"World domination.  Fast"
(By Linus Torvalds)

Re: [PATCH] let XEN depend on PAE

[Arnd Hannemann]

Ian Campbell schrieb:
> On Fri, 2008-02-22 at 12:00 +0100, Arnd Hannemann wrote:
>> As paravirtualized xen guests won't work with !X86_PAE, change the Kconfig
>> accordingly.
> 
> Really? Xen guests should work on non-PAE if you have a non-PAE
> hypervisor (which most distros don't ship but which does exist).

Well if it should work, then something else is broken.
I have a non-PAE hypervisor, still xen guests compiled with !X86_PAE
from 2.6.24.2  and latest git won't work.
All the same with PAE enabled works.

http://lists.xensource.com/archives/html/xen-devel/2008-02/msg00716.html

> 
> Ian.
> 

Best regards,
Arnd

Re: [Xen-devel] [PATCH] let XEN depend on PAE

[Jeremy Fitzhardinge]

Arnd Hannemann wrote:
> As paravirtualized xen guests won't work with !X86_PAE, change the Kconfig
> accordingly.
>   

!PAE is supposed to work, but it is a rarely used configuration.  How 
does it fail?

    J

Re: [Xen-devel] [PATCH] let XEN depend on PAE

[Arnd Hannemann]

Jeremy Fitzhardinge schrieb:
> Arnd Hannemann wrote:
>> As paravirtualized xen guests won't work with !X86_PAE, change the
>> Kconfig
>> accordingly.
>>   
> 
> !PAE is supposed to work, but it is a rarely used configuration.  How
> does it fail?
> 
>    J
> 

This is with 2.6.24.2, but latest-git looks the same:
I also tried with 2.6.23 which crashes instantly, without any output of the guest.

[    0.599806] 1 multicall(s) failed: cpu 0
[    0.599816]   call  1/2: op=26 arg=[c1051860] result=0
[    0.599825]   call  2/2: op=14 arg=[bf9c7000] result=-22
[    0.599841] ------------[ cut here ]------------
[    0.599851] kernel BUG at arch/x86/xen/multicalls.c:103!
[    0.599861] invalid opcode: 0000 [#1] SMP
[    0.599871] Modules linked in:
[    0.599879]
[    0.599885] Pid: 1, comm: init Not tainted (2.6.24.2 #6)
[    0.599895] EIP: 0061:[<c0101b7c>] EFLAGS: 00010202 CPU: 0
[    0.599910] EIP is at xen_mc_flush+0x19c/0x1b0
[    0.599919] EAX: 00000000 EBX: c10510a0 ECX: c1051060 EDX: c1051060
[    0.599930] ESI: 00000002 EDI: 00000001 EBP: c2417c10 ESP: c2417be4
[    0.599940]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: e021
[    0.599951] Process init (pid: 1, ti=c2417000 task=c2416ab0 task.ti=c2417000)
[    0.599960] Stack: c0443c98 00000002 00000002 0000000e bf9c7000 ffffffea c1051060 00000200
[    0.599984]        00000067 c193fffc bf9c7000 c2417c18 c0101112 c2417c5c c0166dfc c193ce40
[    0.600006]        c193e5c0 c0000000 c193e5c0 00001000 c0000000 c193ce40 c198e71c c10331cc
[    0.600029] Call Trace:
[    0.600036]  [<c0107a6a>] show_trace_log_lvl+0x1a/0x30
[    0.600050]  [<c0107b29>] show_stack_log_lvl+0xa9/0xd0
[    0.600062]  [<c0107c1a>] show_registers+0xca/0x1e0
[    0.600074]  [<c0107e4a>] die+0x11a/0x250
[    0.600085]  [<c0108003>] do_trap+0x83/0xb0
[    0.600096]  [<c0108318>] do_invalid_op+0x88/0xa0
[    0.600108]  [<c03e89d2>] error_code+0x72/0x80
[    0.600121]  [<c0101112>] xen_leave_lazy+0x12/0x20
[    0.600134]  [<c0166dfc>] move_page_tables+0x27c/0x300
[    0.600149]  [<c0174762>] setup_arg_pages+0x162/0x2a0
[    0.600162]  [<c019cad3>] load_elf_binary+0x3d3/0x1bd0
[    0.600175]  [<c0173f92>] search_binary_handler+0x92/0x200
[    0.600190]  [<c019b1ef>] load_script+0x1bf/0x200
[    0.600202]  [<c0173f92>] search_binary_handler+0x92/0x200
[    0.600215]  [<c0175bab>] do_execve+0x15b/0x180
[    0.600227]  [<c0104a2e>] sys_execve+0x2e/0x80
[    0.600241]  [<c0106342>] syscall_call+0x7/0xb
[    0.600253]  =======================
[    0.600259] Code: 24 08 89 44 24 0c 89 74 24 04 c7 04 24 98 3c 44 c0 e8 c9 36 02 00 8b 45 ec 83 c3 20 8b 90 00 0b 00 00 39 d6 72 c0 e9 04 ff ff ff <0f> 0b eb fe 0f 0b eb fe 8d b6 00 00 00 00 8d bf 00 00 00 00 55
[    0.600370] EIP: [<c0101b7c>] xen_mc_flush+0x19c/0x1b0 SS:ESP e021:c2417be4
[    0.600393] ---[ end trace a686db401f06e173 ]---
[    0.600403] Kernel panic - not syncing: Attempted to kill init!

full dmesg, config here:
http://lists.xensource.com/archives/html/xen-devel/2008-02/msg00716.html

Best regards,
Arnd Hannemann

Re: [Xen-devel] [PATCH] let XEN depend on PAE

[Jeremy Fitzhardinge]

Arnd Hannemann wrote:
> This is with 2.6.24.2, but latest-git looks the same:
> I also tried with 2.6.23 which crashes instantly, without any output of the guest.
>   

I'm not too surprised.  Non-PAE Xen is a bit of a rarity, and it only 
gets tested rarely.  Chris Wright did spend some time on it a while ago, 
but I don't know that its had any real attention since.  I've been 
making sure non-PAE compiles, but I've been lax about testing it.

This is the first usermode exec, I guess?  The backtrace is a bit odd; 
I've never seen a problem in move_page_tables before.

Does "xm dmesg" tell you what Xen is complaining about?  You may need to 
compile with debug=y in Config.mk.

> [    0.599806] 1 multicall(s) failed: cpu 0
> [    0.599816]   call  1/2: op=26 arg=[c1051860] result=0
> [    0.599825]   call  2/2: op=14 arg=[bf9c7000] result=-22
> [    0.599841] ------------[ cut here ]------------
> [    0.599851] kernel BUG at arch/x86/xen/multicalls.c:103!
> [    0.599861] invalid opcode: 0000 [#1] SMP
> [    0.599871] Modules linked in:
> [    0.599879]
> [    0.599885] Pid: 1, comm: init Not tainted (2.6.24.2 #6)
> [    0.599895] EIP: 0061:[<c0101b7c>] EFLAGS: 00010202 CPU: 0
> [    0.599910] EIP is at xen_mc_flush+0x19c/0x1b0
> [    0.599919] EAX: 00000000 EBX: c10510a0 ECX: c1051060 EDX: c1051060
> [    0.599930] ESI: 00000002 EDI: 00000001 EBP: c2417c10 ESP: c2417be4
> [    0.599940]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: e021
> [    0.599951] Process init (pid: 1, ti=c2417000 task=c2416ab0 task.ti=c2417000)
> [    0.599960] Stack: c0443c98 00000002 00000002 0000000e bf9c7000 ffffffea c1051060 00000200
> [    0.599984]        00000067 c193fffc bf9c7000 c2417c18 c0101112 c2417c5c c0166dfc c193ce40
> [    0.600006]        c193e5c0 c0000000 c193e5c0 00001000 c0000000 c193ce40 c198e71c c10331cc
> [    0.600029] Call Trace:
> [    0.600036]  [<c0107a6a>] show_trace_log_lvl+0x1a/0x30
> [    0.600050]  [<c0107b29>] show_stack_log_lvl+0xa9/0xd0
> [    0.600062]  [<c0107c1a>] show_registers+0xca/0x1e0
> [    0.600074]  [<c0107e4a>] die+0x11a/0x250
> [    0.600085]  [<c0108003>] do_trap+0x83/0xb0
> [    0.600096]  [<c0108318>] do_invalid_op+0x88/0xa0
> [    0.600108]  [<c03e89d2>] error_code+0x72/0x80
> [    0.600121]  [<c0101112>] xen_leave_lazy+0x12/0x20
> [    0.600134]  [<c0166dfc>] move_page_tables+0x27c/0x300
> [    0.600149]  [<c0174762>] setup_arg_pages+0x162/0x2a0
> [    0.600162]  [<c019cad3>] load_elf_binary+0x3d3/0x1bd0
> [    0.600175]  [<c0173f92>] search_binary_handler+0x92/0x200
> [    0.600190]  [<c019b1ef>] load_script+0x1bf/0x200
> [    0.600202]  [<c0173f92>] search_binary_handler+0x92/0x200
> [    0.600215]  [<c0175bab>] do_execve+0x15b/0x180
> [    0.600227]  [<c0104a2e>] sys_execve+0x2e/0x80
> [    0.600241]  [<c0106342>] syscall_call+0x7/0xb
> [    0.600253]  =======================
> [    0.600259] Code: 24 08 89 44 24 0c 89 74 24 04 c7 04 24 98 3c 44 c0 e8 c9 36 02 00 8b 45 ec 83 c3 20 8b 90 00 0b 00 00 39 d6 72 c0 e9 04 ff ff ff <0f> 0b eb fe 0f 0b eb fe 8d b6 00 00 00 00 8d bf 00 00 00 00 55
> [    0.600370] EIP: [<c0101b7c>] xen_mc_flush+0x19c/0x1b0 SS:ESP e021:c2417be4
> [    0.600393] ---[ end trace a686db401f06e173 ]---
> [    0.600403] Kernel panic - not syncing: Attempted to kill init!
>
> full dmesg, config here:
> http://lists.xensource.com/archives/html/xen-devel/2008-02/msg00716.html
>
> Best regards,
> Arnd Hannemann
>
>   

    J

Re: [Xen-devel] [PATCH] let XEN depend on PAE

[Arnd Hannemann]

Jeremy Fitzhardinge wrote:
> Arnd Hannemann wrote:
>> This is with 2.6.24.2, but latest-git looks the same:
>> I also tried with 2.6.23 which crashes instantly, without any output
>> of the guest.
>>   
> 
> I'm not too surprised.  Non-PAE Xen is a bit of a rarity, and it only
> gets tested rarely.  Chris Wright did spend some time on it a while ago,
> but I don't know that its had any real attention since.  I've been
> making sure non-PAE compiles, but I've been lax about testing it.
> This is the first usermode exec, I guess?  The backtrace is a bit odd;
> I've never seen a problem in move_page_tables before.

Yes its trying to execute the first script in initramfs, I also tried with initramdisk
and got a similar error. (move_page_tables also involved)

> 
> Does "xm dmesg" tell you what Xen is complaining about?  You may need to
> compile with debug=y in Config.mk.

(XEN) mm.c:645:d44 Non-privileged (44) attempt to map I/O space 00000000

I will recompile with debug=y and post the output.
If I reduce the dom0 memory with dom0_mem=200000 I see something like
00000080 with dom0_mem=800000 I always see 00000000.

> 
>> [    0.599806] 1 multicall(s) failed: cpu 0
>> [    0.599816]   call  1/2: op=26 arg=[c1051860] result=0
>> [    0.599825]   call  2/2: op=14 arg=[bf9c7000] result=-22
>> [    0.599841] ------------[ cut here ]------------
>> [    0.599851] kernel BUG at arch/x86/xen/multicalls.c:103!
>> [    0.599861] invalid opcode: 0000 [#1] SMP
>> [    0.599871] Modules linked in:
>> [    0.599879]
>> [    0.599885] Pid: 1, comm: init Not tainted (2.6.24.2 #6)
>> [    0.599895] EIP: 0061:[<c0101b7c>] EFLAGS: 00010202 CPU: 0
>> [    0.599910] EIP is at xen_mc_flush+0x19c/0x1b0
>> [    0.599919] EAX: 00000000 EBX: c10510a0 ECX: c1051060 EDX: c1051060
>> [    0.599930] ESI: 00000002 EDI: 00000001 EBP: c2417c10 ESP: c2417be4
>> [    0.599940]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: e021
>> [    0.599951] Process init (pid: 1, ti=c2417000 task=c2416ab0
>> task.ti=c2417000)
>> [    0.599960] Stack: c0443c98 00000002 00000002 0000000e bf9c7000
>> ffffffea c1051060 00000200
>> [    0.599984]        00000067 c193fffc bf9c7000 c2417c18 c0101112
>> c2417c5c c0166dfc c193ce40
>> [    0.600006]        c193e5c0 c0000000 c193e5c0 00001000 c0000000
>> c193ce40 c198e71c c10331cc
>> [    0.600029] Call Trace:
>> [    0.600036]  [<c0107a6a>] show_trace_log_lvl+0x1a/0x30
>> [    0.600050]  [<c0107b29>] show_stack_log_lvl+0xa9/0xd0
>> [    0.600062]  [<c0107c1a>] show_registers+0xca/0x1e0
>> [    0.600074]  [<c0107e4a>] die+0x11a/0x250
>> [    0.600085]  [<c0108003>] do_trap+0x83/0xb0
>> [    0.600096]  [<c0108318>] do_invalid_op+0x88/0xa0
>> [    0.600108]  [<c03e89d2>] error_code+0x72/0x80
>> [    0.600121]  [<c0101112>] xen_leave_lazy+0x12/0x20
>> [    0.600134]  [<c0166dfc>] move_page_tables+0x27c/0x300
>> [    0.600149]  [<c0174762>] setup_arg_pages+0x162/0x2a0
>> [    0.600162]  [<c019cad3>] load_elf_binary+0x3d3/0x1bd0
>> [    0.600175]  [<c0173f92>] search_binary_handler+0x92/0x200
>> [    0.600190]  [<c019b1ef>] load_script+0x1bf/0x200
>> [    0.600202]  [<c0173f92>] search_binary_handler+0x92/0x200
>> [    0.600215]  [<c0175bab>] do_execve+0x15b/0x180
>> [    0.600227]  [<c0104a2e>] sys_execve+0x2e/0x80
>> [    0.600241]  [<c0106342>] syscall_call+0x7/0xb
>> [    0.600253]  =======================
>> [    0.600259] Code: 24 08 89 44 24 0c 89 74 24 04 c7 04 24 98 3c 44
>> c0 e8 c9 36 02 00 8b 45 ec 83 c3 20 8b 90 00 0b 00 00 39 d6 72 c0 e9
>> 04 ff ff ff <0f> 0b eb fe 0f 0b eb fe 8d b6 00 00 00 00 8d bf 00 00 00
>> 00 55
>> [    0.600370] EIP: [<c0101b7c>] xen_mc_flush+0x19c/0x1b0 SS:ESP
>> e021:c2417be4
>> [    0.600393] ---[ end trace a686db401f06e173 ]---
>> [    0.600403] Kernel panic - not syncing: Attempted to kill init!
>>
>> full dmesg, config here:
>> http://lists.xensource.com/archives/html/xen-devel/2008-02/msg00716.html
>>
>> Best regards,
>> Arnd Hannemann
>>
>>   
> 
>    J
> 

Re: [Xen-devel] [PATCH] let XEN depend on PAE

[Jeremy Fitzhardinge]

Arnd Hannemann wrote:
> Jeremy Fitzhardinge wrote:
>   
>> Arnd Hannemann wrote:
>>     
>>> This is with 2.6.24.2, but latest-git looks the same:
>>> I also tried with 2.6.23 which crashes instantly, without any output
>>> of the guest.
>>>   
>>>       
>> I'm not too surprised.  Non-PAE Xen is a bit of a rarity, and it only
>> gets tested rarely.  Chris Wright did spend some time on it a while ago,
>> but I don't know that its had any real attention since.  I've been
>> making sure non-PAE compiles, but I've been lax about testing it.
>> This is the first usermode exec, I guess?  The backtrace is a bit odd;
>> I've never seen a problem in move_page_tables before.
>>     
>
> Yes its trying to execute the first script in initramfs, I also tried with initramdisk
> and got a similar error. (move_page_tables also involved)
>
>   
>> Does "xm dmesg" tell you what Xen is complaining about?  You may need to
>> compile with debug=y in Config.mk.
>>     
>
> (XEN) mm.c:645:d44 Non-privileged (44) attempt to map I/O space 00000000
>
> I will recompile with debug=y and post the output.
> If I reduce the dom0 memory with dom0_mem=200000 I see something like
> 00000080 with dom0_mem=800000 I always see 00000000.
>   

That's helpful.  Looks like the mfn is getting mushed to 0.

    J

Re: [Xen-devel] [PATCH] let XEN depend on PAE

[Arnd Hannemann]

Arnd Hannemann wrote:
> Jeremy Fitzhardinge wrote:
>> Arnd Hannemann wrote:
>>> This is with 2.6.24.2, but latest-git looks the same:
>>> I also tried with 2.6.23 which crashes instantly, without any output
>>> of the guest.
>>>   
>> I'm not too surprised.  Non-PAE Xen is a bit of a rarity, and it only
>> gets tested rarely.  Chris Wright did spend some time on it a while ago,
>> but I don't know that its had any real attention since.  I've been
>> making sure non-PAE compiles, but I've been lax about testing it.
>> This is the first usermode exec, I guess?  The backtrace is a bit odd;
>> I've never seen a problem in move_page_tables before.
> 
> Yes its trying to execute the first script in initramfs, I also tried with initramdisk
> and got a similar error. (move_page_tables also involved)
> 
>> Does "xm dmesg" tell you what Xen is complaining about?  You may need to
>> compile with debug=y in Config.mk.
> 
> (XEN) mm.c:645:d44 Non-privileged (44) attempt to map I/O space 00000000
> 
> I will recompile with debug=y and post the output.

I recompiled with debug=y but no more information than above message...

[snip]

Arnd