linux-hyperv.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Dave Hansen <dave.hansen@intel.com>
To: Dexuan Cui <decui@microsoft.com>,
	"Michael Kelley (LINUX)" <mikelley@microsoft.com>,
	"ak@linux.intel.com" <ak@linux.intel.com>,
	"arnd@arndb.de" <arnd@arndb.de>, "bp@alien8.de" <bp@alien8.de>,
	"brijesh.singh@amd.com" <brijesh.singh@amd.com>,
	"Williams, Dan J" <dan.j.williams@intel.com>,
	"dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>,
	Haiyang Zhang <haiyangz@microsoft.com>,
	"hpa@zytor.com" <hpa@zytor.com>,
	"jane.chu@oracle.com" <jane.chu@oracle.com>,
	"kirill.shutemov@linux.intel.com"
	<kirill.shutemov@linux.intel.com>,
	KY Srinivasan <kys@microsoft.com>,
	"linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>,
	"linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>,
	"luto@kernel.org" <luto@kernel.org>,
	"mingo@redhat.com" <mingo@redhat.com>,
	"peterz@infradead.org" <peterz@infradead.org>,
	"rostedt@goodmis.org" <rostedt@goodmis.org>,
	"sathyanarayanan.kuppuswamy@linux.intel.com" 
	<sathyanarayanan.kuppuswamy@linux.intel.com>,
	"seanjc@google.com" <seanjc@google.com>,
	"tglx@linutronix.de" <tglx@linutronix.de>,
	"tony.luck@intel.com" <tony.luck@intel.com>,
	"wei.liu@kernel.org" <wei.liu@kernel.org>,
	"x86@kernel.org" <x86@kernel.org>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 5/6] x86/hyperv: Support hypercalls for TDX guests
Date: Mon, 28 Nov 2022 11:48:07 -0800	[thread overview]
Message-ID: <f6d27366-e083-b362-b44c-eaf4d3365b53@intel.com> (raw)
In-Reply-To: <SA1PR21MB13357B3CC486514D2DF50A4DBF139@SA1PR21MB1335.namprd21.prod.outlook.com>

On 11/28/22 11:37, Dexuan Cui wrote:
>> From: Dave Hansen <dave.hansen@intel.com>
...
>> How do we know, for instance, that no hypercall using this interface
>> will *ever* take the 0x0 physical address as an argument?
> 
> A 0x0 physical address as an argument still works: the 0 is passed
> to the hypervisor using GHCI. I believe Hyper-V interprets the 0 as
> an error (if the param is needed), and returns an "invalid parameter"
> error code to the guest.

I don't see any data in the public documentation to support the claim
that 0x0 is a special argument for either the input or output GPA
parameters.

This is despite some actual discussion on things like their alignment
requirements[1] and interactions with overlay pages.

So, either you are mistaken about that behavior, or it looks like the
documentation needs updating.

1.
https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/hypercall-interface



  reply	other threads:[~2022-11-28 19:48 UTC|newest]

Thread overview: 57+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-11-21 19:51 [PATCH 0/6] Support TDX guests on Hyper-V Dexuan Cui
2022-11-21 19:51 ` [PATCH 1/6] x86/tdx: Support hypercalls for " Dexuan Cui
2022-11-21 20:38   ` Dave Hansen
2022-11-21 23:52     ` Kirill A. Shutemov
2022-11-23  1:37     ` Dexuan Cui
2022-11-23  1:56       ` Dexuan Cui
2022-11-23 16:04         ` Dave Hansen
2022-11-23 18:59           ` Dexuan Cui
2022-11-23  3:52       ` Sathyanarayanan Kuppuswamy
2022-11-23 14:40       ` Kirill A. Shutemov
2022-11-23 18:55         ` Dexuan Cui
2022-11-30 19:14           ` Dexuan Cui
2022-12-02 21:47             ` 'Kirill A. Shutemov'
2022-11-23 16:03       ` Dave Hansen
2022-11-21 19:51 ` [PATCH 2/6] x86/tdx: Retry TDVMCALL_MAP_GPA() when needed Dexuan Cui
2022-11-21 20:55   ` Dave Hansen
2022-11-23  2:55     ` Dexuan Cui
2022-11-22  0:01   ` Kirill A. Shutemov
2022-11-23  3:27     ` Dexuan Cui
2022-11-23 13:30       ` Michael Kelley (LINUX)
2022-11-28  0:07         ` Dexuan Cui
2022-11-21 19:51 ` [PATCH 3/6] x86/tdx: Support vmalloc() for tdx_enc_status_changed() Dexuan Cui
2022-11-21 21:00   ` Dave Hansen
2022-11-23  4:01     ` Dexuan Cui
2022-11-22  0:24   ` Kirill A. Shutemov
2022-11-23 23:51     ` Dexuan Cui
2022-11-24  7:51       ` Kirill A. Shutemov
2022-11-27 20:27         ` Dexuan Cui
2022-11-21 19:51 ` [PATCH 4/6] x86/hyperv: Add hv_isolation_type_tdx() to detect TDX guests Dexuan Cui
2022-11-21 21:01   ` Dave Hansen
2022-11-21 21:48     ` Borislav Petkov
2022-11-22  0:32   ` Sathyanarayanan Kuppuswamy
2022-11-23 19:13     ` Dexuan Cui
2022-11-21 19:51 ` [PATCH 5/6] x86/hyperv: Support hypercalls for " Dexuan Cui
2022-11-21 20:05   ` Dave Hansen
2022-11-23  2:14     ` Dexuan Cui
2022-11-23 14:47       ` Kirill A. Shutemov
2022-11-23 18:13         ` Dexuan Cui
2022-11-23 18:18         ` Sathyanarayanan Kuppuswamy
2022-11-23 19:07           ` Dexuan Cui
2022-11-23 14:45   ` Michael Kelley (LINUX)
2022-11-28  0:58     ` Dexuan Cui
2022-11-28  1:20       ` Michael Kelley (LINUX)
2022-11-28  1:36         ` Dexuan Cui
2022-11-28  1:21       ` Sathyanarayanan Kuppuswamy
2022-11-28  1:55         ` Dexuan Cui
2022-11-28 15:22       ` Dave Hansen
2022-11-28 19:03         ` Dexuan Cui
2022-11-28 19:11           ` Dave Hansen
2022-11-28 19:37             ` Dexuan Cui
2022-11-28 19:48               ` Dave Hansen [this message]
2022-11-28 20:36                 ` Dexuan Cui
2022-11-28 21:15                   ` Dave Hansen
2022-11-28 21:53                     ` Dexuan Cui
2022-11-21 19:51 ` [PATCH 6/6] Drivers: hv: vmbus: Support " Dexuan Cui
2023-01-06 11:00   ` Zhi Wang
2023-01-09  6:59     ` Dexuan Cui

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=f6d27366-e083-b362-b44c-eaf4d3365b53@intel.com \
    --to=dave.hansen@intel.com \
    --cc=ak@linux.intel.com \
    --cc=arnd@arndb.de \
    --cc=bp@alien8.de \
    --cc=brijesh.singh@amd.com \
    --cc=dan.j.williams@intel.com \
    --cc=dave.hansen@linux.intel.com \
    --cc=decui@microsoft.com \
    --cc=haiyangz@microsoft.com \
    --cc=hpa@zytor.com \
    --cc=jane.chu@oracle.com \
    --cc=kirill.shutemov@linux.intel.com \
    --cc=kys@microsoft.com \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-hyperv@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@kernel.org \
    --cc=mikelley@microsoft.com \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --cc=sathyanarayanan.kuppuswamy@linux.intel.com \
    --cc=seanjc@google.com \
    --cc=tglx@linutronix.de \
    --cc=tony.luck@intel.com \
    --cc=wei.liu@kernel.org \
    --cc=x86@kernel.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).