From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH 1/1] x86: Set regs->entry_vector for
	early_page_fault
Date: Mon, 13 Apr 2015 17:09:05 +0100
Message-ID: <552BEA21.7030301@citrix.com>
References: <1428941077-18458-1-git-send-email-dslutz@verizon.com>
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To: Don Slutz <dslutz@verizon.com>, xen-devel@lists.xen.org
Cc: Keir Fraser <keir@xen.org>, Jan Beulich <jbeulich@suse.com>
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On 13/04/15 17:04, Don Slutz wrote:
> This changes:
>
> (XEN) Early fatal page fault at e008:ffff82d080164252 (cr2=0000000000000000, ec=0000)
> (XEN) ----[ Xen-4.6-unstable  x86_64  debug=y  Not tainted ]----
> (XEN) CPU:    0
> (XEN) RIP:    e008:[<ffff82d080164252>] arch_domain_create+0x3e/0x4ef
> ...
> (XEN) Xen call trace:
> (XEN)    [<ffff82d080164252>] arch_domain_create+0x3e/0x4ef
> (XEN)    [<ffff82d080105262>] domain_create+0x384/0x556
> (XEN)    [<ffff82d0802a0de4>] scheduler_init+0x1c4/0x244
> (XEN)    [<ffff82d0802be359>] __start_xen+0x1d0e/0x22a1
> (XEN)    [<ffff82d080100067>] __high_start+0x53/0x58
> (XEN)
> (XEN)
> (XEN) ****************************************
> (XEN) Panic on CPU 0:
> (XEN) FATAL TRAP: vector = 0 (divide error)
> (XEN) [error_code=0000] , IN INTERRUPT CONTEXT
> (XEN) ****************************************
> ...
>
> to:
>
> (XEN) Early fatal page fault at e008:ffff82d080164252 (cr2=0000000000000000, ec=0000)
> (XEN) ----[ Xen-4.6-unstable  x86_64  debug=y  Not tainted ]----
> (XEN) CPU:    0
> (XEN) RIP:    e008:[<ffff82d080164252>] arch_domain_create+0x3e/0x4ef
> ...
> (XEN) Xen call trace:
> (XEN)    [<ffff82d080164252>] arch_domain_create+0x3e/0x4ef
> (XEN)    [<ffff82d080105262>] domain_create+0x384/0x556
> (XEN)    [<ffff82d0802a0de4>] scheduler_init+0x1c4/0x244
> (XEN)    [<ffff82d0802be359>] __start_xen+0x1d0e/0x22a1
> (XEN)    [<ffff82d080100067>] __high_start+0x53/0x58
> (XEN)
> (XEN) Faulting linear address: 0000000000000000
> (XEN) Pagetable walk from 0000000000000000:
> (XEN)  L4[0x000] = 000000083a1a6063 ffffffffffffffff
> (XEN)  L3[0x000] = 000000083a1a5063 ffffffffffffffff
> (XEN)  L2[0x000] = 000000083a1a4063 ffffffffffffffff
> (XEN)  L1[0x000] = 0000000000000000 ffffffffffffffff
> (XEN)
> (XEN) ****************************************
> (XEN) Panic on CPU 0:
> (XEN) FATAL TRAP: vector = 14 (page fault)
> (XEN) [error_code=0000] , IN INTERRUPT CONTEXT
> (XEN) ****************************************
> ...
>
> Signed-off-by: Don Slutz <dslutz@verizon.com>

Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

> ---
>  xen/arch/x86/x86_64/entry.S | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S
> index 2d25d57..7e63e64 100644
> --- a/xen/arch/x86/x86_64/entry.S
> +++ b/xen/arch/x86/x86_64/entry.S
> @@ -626,6 +626,7 @@ ENTRY(double_fault)
>  
>          .pushsection .init.text, "ax", @progbits
>  ENTRY(early_page_fault)
> +        movl  $TRAP_page_fault,4(%rsp)
>          SAVE_ALL
>          movq  %rsp,%rdi
>          call  do_early_page_fault