All of lore.kernel.org
 help / color / mirror / Atom feed
From: Gerd Hoffmann <kraxel@redhat.com>
To: "Richard W.M. Jones" <rjones@redhat.com>
Cc: "Marc Marí" <markmb@redhat.com>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Why is SeaBIOS used with -kernel?
Date: Mon, 21 Mar 2016 08:58:27 +0100	[thread overview]
Message-ID: <1458547107.4299.7.camel@redhat.com> (raw)
In-Reply-To: <20160319203124.GB19398@redhat.com>

On Sa, 2016-03-19 at 20:31 +0000, Richard W.M. Jones wrote:
> I've been analyzing the libguestfs appliance[1] boot time.  See
> attached file, especially the end of it.
> 
> About 50% of the boot time is because of SeaBIOS.

And the bulk of that is loading the kernel from fw_cfg.

> I'm using the qemu -kernel option.  I understand that the kernel needs
> some BIOS features, eg. video stuff, E820.  But kvmtool comes with a
> really minimal BIOS that implements a tiny number of calls[2] and is
> far faster than SeaBIOS.
> 
> Is there something I'm missing, or for Linux + -kernel could we use a
> much simpler BIOS?

marc (cc'ed) worked on porting the linuxboot option rom over to use the
new fwcfg dma interface, which should make things a order of magnitude
faster.  That seems to be stalled though.  Marc?

cheers,
  Gerd

  reply	other threads:[~2016-03-21  7:58 UTC|newest]

Thread overview: 55+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-03-19 20:31 [Qemu-devel] Why is SeaBIOS used with -kernel? Richard W.M. Jones
2016-03-21  7:58 ` Gerd Hoffmann [this message]
2016-03-21  8:37   ` Richard W.M. Jones
2016-03-21  9:40     ` Gerd Hoffmann
2016-03-31  9:21 ` Stefan Hajnoczi
2016-03-31 16:22   ` Kevin O'Connor
     [not found]     ` <20160331221039.GA32728@redhat.com>
2016-03-31 22:17       ` Richard W.M. Jones
2016-03-31 22:44         ` Kevin O'Connor
2016-04-01  7:55           ` Richard W.M. Jones
2016-04-01  8:03             ` Paolo Bonzini
2016-04-01  8:47               ` Richard W.M. Jones
2016-04-01  8:51                 ` Paolo Bonzini
2016-04-01  8:57                   ` Richard W.M. Jones
2016-04-01  9:05                     ` Paolo Bonzini
2016-04-01  8:02           ` Richard W.M. Jones
2016-04-01  8:11             ` Paolo Bonzini
2016-04-01  8:14               ` Richard W.M. Jones
2016-04-01  8:24                 ` Paolo Bonzini
2016-04-01  8:44                   ` Richard W.M. Jones
2016-04-01  8:47                     ` Paolo Bonzini
2016-04-01  8:49                       ` Vasiliy Tolstov
2016-04-01  9:16                     ` Dr. David Alan Gilbert
2016-04-01  9:18                     ` Gerd Hoffmann
2016-04-01 10:17                       ` Richard W.M. Jones
2016-04-01 11:07                         ` Gerd Hoffmann
2016-04-01 11:11                           ` Richard W.M. Jones
2016-04-01 11:20                             ` Richard W.M. Jones
2016-04-01 11:21                               ` Paolo Bonzini
2016-04-01 11:26                                 ` Richard W.M. Jones
2016-04-05  4:38                               ` Kevin Wolf
2016-04-05  8:04                                 ` Richard W.M. Jones
2016-04-05  8:11                                   ` Kevin Wolf
2016-04-05  9:19                                     ` Richard W.M. Jones
2016-04-05  9:26                                       ` Kevin Wolf
2016-04-01 11:32                             ` Gerd Hoffmann
2016-04-01 11:49                               ` Richard W.M. Jones
2016-04-01 15:35                                 ` Kevin O'Connor
2016-04-01 16:03                                   ` Paolo Bonzini
2016-04-01 18:41                                   ` Richard W.M. Jones
2016-04-01 18:59                                     ` Richard W.M. Jones
2016-04-01 19:04                                       ` Kevin O'Connor
2016-04-01 19:10                                         ` Richard W.M. Jones
2016-04-01 19:15                                           ` Richard W.M. Jones
2016-04-01 19:44                                             ` Kevin O'Connor
2016-04-01 20:25                                               ` Richard W.M. Jones
2016-04-01 20:05                                     ` Kevin O'Connor
2016-04-01 20:46                                       ` Richard W.M. Jones
2016-04-01 22:25                                         ` Kevin O'Connor
2016-04-02  7:51                                           ` Richard W.M. Jones
2016-04-02  5:30                                       ` Paolo Bonzini
2016-04-01 15:08                           ` Kevin O'Connor
2016-04-01 14:58                     ` Kevin O'Connor
2016-04-01 15:06                       ` Richard W.M. Jones
2016-04-01 15:14                         ` Kevin O'Connor
2016-04-01  8:19               ` Richard W.M. Jones

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=1458547107.4299.7.camel@redhat.com \
    --to=kraxel@redhat.com \
    --cc=markmb@redhat.com \
    --cc=qemu-devel@nongnu.org \
    --cc=rjones@redhat.com \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.