From: "Jan Beulich" <JBeulich@suse.com>
To: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Juergen Gross <JGross@suse.com>,
sstabellini@kernel.org, andrew.cooper3@citrix.com,
cardoe@cardoe.com, pgnet.dev@gmail.com, ning.sun@intel.com,
julien.grall@arm.com, david.vrabel@citrix.com,
xen-devel@lists.xenproject.org, qiaowei.ren@intel.com,
gang.wei@intel.com, fu.wei@linaro.org
Subject: Re: [PATCH v7 12/14] x86: make Xen early boot code relocatable
Date: Wed, 28 Sep 2016 04:19:49 -0600 [thread overview]
Message-ID: <57EBB56502000078001133BF@prv-mh.provo.novell.com> (raw)
In-Reply-To: <20160928095633.GQ28753@olila.local.net-space.pl>
>>> On 28.09.16 at 11:56, <daniel.kiper@oracle.com> wrote:
> On Wed, Sep 28, 2016 at 03:06:31AM -0600, Jan Beulich wrote:
>> >>> On 27.09.16 at 21:55, <daniel.kiper@oracle.com> wrote:
>> > On Mon, Sep 26, 2016 at 09:03:30AM -0600, Jan Beulich wrote:
>> >> >>> On 23.09.16 at 23:47, <daniel.kiper@oracle.com> wrote:
>> >> > +1: mov %eax,sym_fs(l2_bootmap)-8(%ebx,%ecx,8)
>> >> > + mov %eax,sym_fs(l2_identmap)-8(%ebx,%ecx,8)
>> >> > + sub $(1<<L2_PAGETABLE_SHIFT),%eax
>> >> > + loop 1b
>> >> > +
>> >> > + /* Initialize L3 boot-map page directory entry. */
>> >> > + lea __PAGE_HYPERVISOR+(L2_PAGETABLE_ENTRIES*8)*3+sym_esi(l2_bootmap),%eax
>> >> > + mov $4,%ecx
>> >> > +1: mov %eax,sym_fs(l3_bootmap)-8(,%ecx,8)
>> >> > + sub $(L2_PAGETABLE_ENTRIES*8),%eax
>> >> > + loop 1b
>> >> >
>> >> > /*
>> >> > * During boot, hook 4kB mappings of first 2MB of memory into L2.
>> >> > - * This avoids mixing cachability for the legacy VGA region, and is
>> >> > - * corrected when Xen relocates itself.
>> >> > + * This avoids mixing cachability for the legacy VGA region.
>> >> > */
>> >> > - mov $sym_phys(l1_identmap)+__PAGE_HYPERVISOR,%edi
>> >> > - mov %edi,sym_phys(l2_xenmap)
>> >> > + lea __PAGE_HYPERVISOR+sym_esi(l1_identmap),%edi
>> >> > + mov %edi,sym_fs(l2_bootmap)
>> >>
>> >> Switching from l2_xenmap to l2_bootmap here?
>> >
>> > Do we need first 2 MiB mapped in Xen image mapping? It looks that we do not.
>> > Am I missing something?
>>
>> My point here isn't that the change is wrong, but that it's not
>> immediately obvious and hence should be explained in the commit
>> message. After all the need for the mapping of these 2Mb does not
>> - aiui - go away with this patch, but (presumably) with the earlier one
>> moving the load address up to 2Mb. I.e. it can generally be viewed as
>> an independent adjustment.
>
> Probably. Should I move this change to patch #10 (x86: change default load
> address from 1 MiB to 2 MiB) or leave it here with relevant comment?
> Or do you wish separate patch for it?
I think putting it in the other patch would be best, unless it would
end up as non-obvious as it did here, in which case a separate
patch would probably be better.
Jan
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
next prev parent reply other threads:[~2016-09-28 10:19 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-23 21:47 [PATCH v7 00/14] x86: multiboot2 protocol support Daniel Kiper
2016-09-23 21:47 ` [PATCH v7 01/14] x86: move xen ELF end of image to 16 MiB Daniel Kiper
2016-09-26 10:39 ` Jan Beulich
2016-09-26 11:34 ` Daniel Kiper
2016-09-26 12:32 ` Jan Beulich
2016-09-27 17:42 ` Daniel Kiper
2016-09-23 21:47 ` [PATCH v7 02/14] x86: properly calculate xen ELF end of image address Daniel Kiper
2016-09-26 10:45 ` Jan Beulich
2016-09-26 12:06 ` Daniel Kiper
2016-09-26 12:34 ` Jan Beulich
2016-09-23 21:47 ` [PATCH v7 03/14] x86: add multiboot2 protocol support Daniel Kiper
2016-09-26 13:18 ` Jan Beulich
2016-09-23 21:47 ` [PATCH v7 04/14] efi: create efi_enabled() Daniel Kiper
2016-09-23 21:47 ` [PATCH v7 05/14] x86: allow EFI reboot method neither on EFI platforms Daniel Kiper
2016-09-23 21:47 ` [PATCH v7 06/14] efi: build xen.gz with EFI code Daniel Kiper
2016-09-23 21:47 ` [PATCH RFC v7 07/14] efi: create new early memory allocator Daniel Kiper
2016-09-23 23:35 ` Julien Grall
2016-09-26 6:53 ` Jan Beulich
2016-09-26 20:01 ` Julien Grall
2016-09-27 8:06 ` Jan Beulich
2016-09-27 23:23 ` Julien Grall
2016-09-26 13:37 ` Jan Beulich
2016-09-27 17:49 ` Daniel Kiper
2016-09-28 8:48 ` Jan Beulich
2016-09-23 21:47 ` [PATCH v7 08/14] x86: add multiboot2 protocol support for EFI platforms Daniel Kiper
2016-09-26 13:47 ` Jan Beulich
2016-09-27 18:11 ` Daniel Kiper
2016-09-28 8:57 ` Jan Beulich
2016-09-28 9:39 ` Daniel Kiper
2016-09-28 10:16 ` Jan Beulich
2016-09-26 14:19 ` Andrew Cooper
2016-09-26 14:33 ` Jan Beulich
2016-09-26 14:40 ` Andrew Cooper
2016-09-26 15:12 ` Jan Beulich
2016-09-27 18:21 ` Daniel Kiper
2016-09-28 8:58 ` Jan Beulich
2016-09-23 21:47 ` [PATCH v7 09/14] x86/boot: implement early command line parser in C Daniel Kiper
2016-09-26 13:49 ` Jan Beulich
2016-09-23 21:47 ` [PATCH v7 10/14] x86: change default load address from 1 MiB to 2 MiB Daniel Kiper
2016-09-23 21:47 ` [PATCH v7 11/14] x86/setup: use XEN_IMG_OFFSET instead of Daniel Kiper
2016-09-23 21:47 ` [PATCH v7 12/14] x86: make Xen early boot code relocatable Daniel Kiper
2016-09-26 15:03 ` Jan Beulich
2016-09-27 19:55 ` Daniel Kiper
2016-09-28 9:06 ` Jan Beulich
2016-09-28 9:56 ` Daniel Kiper
2016-09-28 10:19 ` Jan Beulich [this message]
2016-09-23 21:47 ` [PATCH v7 13/14] x86/boot: rename sym_phys() to sym_offs() Daniel Kiper
2016-09-26 15:47 ` Jan Beulich
2016-09-23 21:47 ` [PATCH v7 14/14] x86: add multiboot2 protocol support for relocatable images Daniel Kiper
2016-09-26 15:53 ` Jan Beulich
2016-09-27 20:07 ` Daniel Kiper
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=57EBB56502000078001133BF@prv-mh.provo.novell.com \
--to=jbeulich@suse.com \
--cc=JGross@suse.com \
--cc=andrew.cooper3@citrix.com \
--cc=cardoe@cardoe.com \
--cc=daniel.kiper@oracle.com \
--cc=david.vrabel@citrix.com \
--cc=fu.wei@linaro.org \
--cc=gang.wei@intel.com \
--cc=julien.grall@arm.com \
--cc=ning.sun@intel.com \
--cc=pgnet.dev@gmail.com \
--cc=qiaowei.ren@intel.com \
--cc=sstabellini@kernel.org \
--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).