From: Andrew Cooper <andrew.cooper3@citrix.com>
To: "Roger Pau Monné" <roger.pau@citrix.com>,
"Jan Beulich" <JBeulich@suse.com>
Cc: xen-devel@lists.xenproject.org,
Boris Ostrovsky <boris.ostrovsky@oracle.com>,
David Vrabel <david.vrabel@citrix.com>,
Ian Campbell <ian.campbell@citrix.com>
Subject: Re: [PATCH v3 07/32] xen/x86: fix arch_set_info_guest for HVM guests
Date: Wed, 5 Aug 2015 16:39:08 +0100 [thread overview]
Message-ID: <55C22E1C.5020703@citrix.com> (raw)
In-Reply-To: <55C1DD1C.3060108@citrix.com>
On 05/08/15 10:53, Roger Pau Monné wrote:
> El 04/08/15 a les 20.08, Andrew Cooper ha escrit:
>> On 03/08/15 18:31, Roger Pau Monné wrote:
>>>> Therefore, I am leaning slightly towards the specify the internals side
>>>> of things, which removes some complexity from the Xen side of the hypercall.
>>> I've updated the proposed structure, so now it looks like:
>>>
>>> (I still need to figure out how to order the bits in the access rights
>>> (_ar) fields.)
>> All struct's need a flags register.
> I was unsure about adding the {e/r}flags register, I will add it in new
> versions.
For first-gen VT-x, CR0.PE in unable to be cleared. HVMLoader has to
do a dance with vm86 mode, which is where HVM_PARAM_IDENT_PT gets used.
I don't realistically expect this to be a problem for DMlite guests.
>
>>> struct vcpu_hvm_x86_16 {
>>> uint16_t ax;
>>> uint16_t cx;
>>> uint16_t dx;
>>> uint16_t bx;
>>> uint16_t sp;
>>> uint16_t bp;
>>> uint16_t si;
>>> uint16_t di;
>>> uint16_t ip;
>>>
>>> uint32_t cr[8];
>> Definitely no need for anything other than cr0 and 4 in 16 bit mode.
> Yes. Would you rather prefer to spell out the exact control registers
> that are going to be used instead of using an array?
I would suggest so.
CRs 1,5-7 are unconditionally #UD to attempt to use. CR2 is useless
until you enter the #PF handler. CR8 may (hardware dependent) have the
TPR in it, which is useless until the IDT is set up and interrupts have
been enabled.
>
> For 16bit mode this is going to be CR0/CR4, for 32bit or long mode mode
> CR0/CR3/CR4.
Agreed.
>
>>> uint32_t cs_base;
>>> uint32_t ds_base;
>>> uint32_t ss_base;
>>> uint32_t cs_limit;
>>> uint32_t ds_limit;
>>> uint32_t ss_limit;
>>> uint16_t cs_ar;
>>> uint16_t ds_ar;
>>> uint16_t ss_ar;
>>> };
>>>
>>> struct vcpu_hvm_x86_32 {
>>> uint32_t eax;
>>> uint32_t ecx;
>>> uint32_t edx;
>>> uint32_t ebx;
>>> uint32_t esp;
>>> uint32_t ebp;
>>> uint32_t esi;
>>> uint32_t edi;
>>> uint32_t eip;
>>>
>>> uint32_t cr[8];
>> Don't need cr's 5-8.
>>
>>> uint64_t efer;
>>>
>>> uint32_t cs_base;
>>> uint32_t ds_base;
>>> uint32_t ss_base;
>>> uint32_t cs_limit;
>>> uint32_t ds_limit;
>>> uint32_t ss_limit;
>>> uint16_t cs_ar;
>>> uint16_t ds_ar;
>>> uint16_t ss_ar;
>> You need selector entries for each segment as well.
> Really? What's the point in having the selector if we don't have a GDT,
> and we allow loading the cached part, which is the relevant one.
push %cs; push 1f; lret
At all points when segment details are updated, it is the responsibility
of software to ensure that the details match with the GDT/LDT entry.
See for example the Intel and AMD manuals for syscall/sysenter where
similar "updating segment details behind the scenes" occurs.
>
>>> };
>>>
>>> struct vcpu_hvm_x86_64 {
>>> uint64_t rax;
>>> uint64_t rcx;
>>> uint64_t rdx;
>>> uint64_t rbx;
>>> uint64_t rsp;
>>> uint64_t rbp;
>>> uint64_t rsi;
>>> uint64_t rdi;
>>> uint64_t r8;
>>> uint64_t r9;
>>> uint64_t r10;
>>> uint64_t r11;
>>> uint64_t r12;
>>> uint64_t r13;
>>> uint64_t r14;
>>> uint64_t r15;
>>> uint64_t rip;
>>>
>>> uint64_t cr[8];
>>> uint64_t efer;
>> What has happened to the segment information? It cannot be omitted
>> completely, even in 64bit.
> I had in mind to set them to the values required for long mode:
>
> base = 0
> limit = 0xffff
>
> and the attributes field for CS to:
>
> ar = 0x29b (L bit set)
>
> And for SS/DS:
>
> ar = 0x093
>
> But maybe it makes sense to allow setting them in case someone wants to
> start in compatibility mode.
Agreed.
~Andrew
next prev parent reply other threads:[~2015-08-05 15:39 UTC|newest]
Thread overview: 121+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-03 11:34 [PATCH v3 00/32] Introduce HVM without dm and new boot ABI Roger Pau Monne
2015-07-03 11:34 ` [PATCH v3 01/32] libxc: split x86 HVM setup_guest into smaller logical functions Roger Pau Monne
2015-07-06 10:45 ` Andrew Cooper
2015-07-28 11:22 ` Wei Liu
2015-07-03 11:34 ` [PATCH v3 02/32] libxc: unify xc_dom_p2m_{host/guest} Roger Pau Monne
2015-07-06 10:49 ` Andrew Cooper
2015-07-28 11:22 ` Wei Liu
2015-07-03 11:34 ` [PATCH v3 03/32] libxc: introduce the notion of a container type Roger Pau Monne
2015-07-06 12:01 ` Andrew Cooper
2015-07-28 11:22 ` Wei Liu
2015-07-03 11:34 ` [PATCH v3 04/32] libxc: introduce a domain loader for HVM guest firmware Roger Pau Monne
2015-07-06 12:11 ` Andrew Cooper
2015-07-28 11:22 ` Wei Liu
2015-07-03 11:34 ` [PATCH v3 05/32] libxc: make arch_setup_meminit a xc_dom_arch hook Roger Pau Monne
2015-07-06 12:23 ` Andrew Cooper
2015-07-27 10:40 ` Roger Pau Monné
2015-07-28 11:22 ` Wei Liu
2015-07-03 11:34 ` [PATCH v3 06/32] libxc: make arch_setup_boot{init/late} xc_dom_arch hooks Roger Pau Monne
2015-07-06 12:27 ` Andrew Cooper
2015-07-28 11:22 ` Wei Liu
2015-07-03 11:34 ` [PATCH v3 07/32] xen/x86: fix arch_set_info_guest for HVM guests Roger Pau Monne
2015-07-06 12:58 ` Andrew Cooper
2015-07-23 10:14 ` Roger Pau Monné
2015-07-10 18:39 ` Konrad Rzeszutek Wilk
2015-07-10 18:47 ` Konrad Rzeszutek Wilk
2015-07-23 10:17 ` Roger Pau Monné
2015-07-13 14:01 ` Jan Beulich
2015-07-23 10:25 ` Roger Pau Monné
2015-07-23 11:29 ` Jan Beulich
2015-07-23 11:41 ` Ian Campbell
2015-07-23 15:10 ` Roger Pau Monné
2015-07-23 15:32 ` Jan Beulich
2015-07-23 15:48 ` Roger Pau Monné
2015-07-23 15:58 ` Jan Beulich
2015-07-23 16:00 ` Ian Campbell
2015-07-23 16:15 ` Andrew Cooper
2015-07-23 16:19 ` Jan Beulich
2015-07-23 16:49 ` Andrew Cooper
2015-07-23 17:06 ` Roger Pau Monné
2015-07-23 16:56 ` Roger Pau Monné
2015-07-23 17:12 ` Andrew Cooper
2015-07-24 8:22 ` Jan Beulich
2015-07-24 9:59 ` Roger Pau Monné
2015-07-24 10:46 ` Jan Beulich
2015-07-24 12:11 ` Roger Pau Monné
2015-07-24 12:44 ` Jan Beulich
2015-07-24 15:26 ` Roger Pau Monné
2015-07-24 15:49 ` Jan Beulich
2015-07-24 16:54 ` Roger Pau Monné
2015-07-24 17:36 ` Konrad Rzeszutek Wilk
2015-07-27 11:55 ` Roger Pau Monné
2015-08-03 16:55 ` Andrew Cooper
2015-08-03 17:31 ` Roger Pau Monné
2015-08-04 18:08 ` Andrew Cooper
2015-08-05 9:53 ` Roger Pau Monné
2015-08-05 15:39 ` Andrew Cooper [this message]
2015-08-05 16:40 ` Roger Pau Monné
2015-08-05 16:46 ` Andrew Cooper
2015-08-05 17:11 ` Roger Pau Monné
2015-08-05 19:00 ` Andrew Cooper
2015-08-07 12:15 ` Tim Deegan
2015-08-11 7:26 ` Jan Beulich
2015-07-24 11:11 ` Andrew Cooper
2015-07-24 11:28 ` Ian Campbell
2015-07-24 11:49 ` Jan Beulich
2015-07-24 11:46 ` Jan Beulich
2015-07-24 11:49 ` Roger Pau Monné
2015-07-24 12:41 ` Jan Beulich
2015-07-24 15:28 ` Roger Pau Monné
2015-07-03 11:34 ` [PATCH v3 08/32] libxc: introduce a xc_dom_arch for hvm-3.0-x86_32 guests Roger Pau Monne
2015-07-06 13:40 ` Andrew Cooper
2015-07-03 11:34 ` [PATCH v3 09/32] libxl: switch HVM domain building to use xc_dom_* helpers Roger Pau Monne
2015-07-28 11:22 ` Wei Liu
2015-07-28 14:26 ` Roger Pau Monné
2015-07-28 14:29 ` Wei Liu
2015-07-03 11:34 ` [PATCH v3 10/32] libxc: remove dead HVM building code Roger Pau Monne
2015-07-06 13:46 ` Andrew Cooper
2015-07-23 10:27 ` Roger Pau Monné
2015-07-03 11:34 ` [PATCH v3 11/32] xen/x86: add bitmap of enabled emulated devices Roger Pau Monne
2015-07-06 14:10 ` Andrew Cooper
2015-07-07 7:26 ` Jan Beulich
2015-07-23 10:29 ` Roger Pau Monné
2015-07-03 11:34 ` [PATCH v3 12/32] xen/x86: allow disabling the emulated local apic Roger Pau Monne
2015-07-03 11:34 ` [PATCH v3 13/32] xen/x86: allow disabling the emulated HPET Roger Pau Monne
2015-07-03 11:34 ` [PATCH v3 14/32] xen/x86: allow disabling the pmtimer Roger Pau Monne
2015-07-03 11:34 ` [PATCH v3 15/32] xen/x86: allow disabling the emulated RTC Roger Pau Monne
2015-07-03 11:34 ` [PATCH v3 16/32] xen/x86: allow disabling the emulated IO APIC Roger Pau Monne
2015-07-03 11:34 ` [PATCH v3 17/32] xen/x86: allow disabling the emulated PIC Roger Pau Monne
2015-07-03 11:34 ` [PATCH v3 18/32] xen/x86: allow disabling the emulated pmu Roger Pau Monne
2015-07-03 11:34 ` [PATCH v3 19/32] xen/x86: allow disabling the emulated VGA Roger Pau Monne
2015-07-03 11:34 ` [PATCH v3 20/32] xen/x86: allow disabling the emulated IOMMU Roger Pau Monne
2015-07-03 11:34 ` [PATCH v3 21/32] xen/x86: allow disabling all emulated devices inside of Xen Roger Pau Monne
2015-07-03 11:35 ` [PATCH v3 22/32] elfnotes: intorduce a new PHYS_ENTRY elfnote Roger Pau Monne
2015-07-03 11:35 ` [PATCH v3 23/32] libxc: allow creating domains without emulated devices Roger Pau Monne
2015-07-28 11:22 ` Wei Liu
2015-07-03 11:35 ` [PATCH v3 24/32] xen: allow HVM guests to use XENMEM_memory_map Roger Pau Monne
2015-07-03 11:35 ` [PATCH v3 25/32] xen/x86: allow HVM guests to use hypercalls to bring up vCPUs Roger Pau Monne
2015-07-03 11:35 ` [PATCH v3 26/32] xenconsole: try to attach to PV console if HVM fails Roger Pau Monne
2015-07-14 13:46 ` Stefano Stabellini
2015-07-23 10:30 ` Roger Pau Monné
2015-07-03 11:35 ` [PATCH v3 27/32] libxc: change the position of the special pages Roger Pau Monne
2015-07-03 15:36 ` Roger Pau Monné
2015-07-10 19:06 ` Konrad Rzeszutek Wilk
2015-07-23 10:42 ` Roger Pau Monné
2015-07-03 11:35 ` [PATCH v3 28/32] libxc/xen: introduce HVM_PARAM_CMDLINE_PFN Roger Pau Monne
2015-07-03 11:35 ` [PATCH v3 29/32] libxc/xen: introduce HVM_PARAM_FIRST_FREE_PFN Roger Pau Monne
2015-07-10 19:05 ` Konrad Rzeszutek Wilk
2015-07-23 10:46 ` Roger Pau Monné
2015-07-03 11:35 ` [PATCH v3 30/32] libxc/xen: introduce HVM_PARAM_MODLIST_PFN Roger Pau Monne
2015-07-03 11:35 ` [PATCH v3 31/32] libxc: switch xc_dom_elfloader to be used with HVMlite domains Roger Pau Monne
2015-07-10 19:07 ` Konrad Rzeszutek Wilk
2015-07-23 10:48 ` Roger Pau Monné
2015-07-03 11:35 ` [PATCH v3 32/32] libxl: allow the creation of HVM domains without a device model Roger Pau Monne
2015-07-28 11:22 ` Wei Liu
2015-07-29 14:43 ` Roger Pau Monné
2015-07-29 14:50 ` Wei Liu
2015-07-29 14:58 ` Andrew Cooper
2015-07-03 16:19 ` [PATCH v3 00/32] Introduce HVM without dm and new boot ABI David Vrabel
2015-07-03 16:36 ` Roger Pau Monné
2015-07-10 17:44 ` Konrad Rzeszutek Wilk
2015-07-10 18:01 ` Konrad Rzeszutek Wilk
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=55C22E1C.5020703@citrix.com \
--to=andrew.cooper3@citrix.com \
--cc=JBeulich@suse.com \
--cc=boris.ostrovsky@oracle.com \
--cc=david.vrabel@citrix.com \
--cc=ian.campbell@citrix.com \
--cc=roger.pau@citrix.com \
--cc=xen-devel@lists.xenproject.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).