Kernel KVM virtualization development
 help / color / mirror / Atom feed
From: Thomas Gleixner <tglx@linutronix.de>
To: Alex Williamson <alex.williamson@redhat.com>
Cc: Richard Weinberger <richard@nod.at>,
	kvm@vger.kernel.org, avi@redhat.com,
	Marcelo Tosatti <mtosatti@redhat.com>,
	Bjorn Helgaas <bhelgaas@google.com>
Subject: Re: [PATCH 2/2] Device assignment: Fix MSI IRQ affinity setting
Date: Thu, 24 May 2012 23:39:08 +0200 (CEST)	[thread overview]
Message-ID: <alpine.LFD.2.02.1205242323230.3231@ionos> (raw)
In-Reply-To: <1337883627.4714.32.camel@ul30vt>

On Thu, 24 May 2012, Alex Williamson wrote:
> On Thu, 2012-05-24 at 18:02 +0100, Richard Weinberger wrote:
> > +            if (address == msi_start + PCI_MSI_DATA_32)
> > +                handle_cfg_write_msi(pci_dev, assigned_dev);
> 
> Why didn't we just use range_covers_byte(address, len, pci_dev->msi_cap
> + PCI_MSI_DATA_32) to start with?  But how does this handle the enable
> bit?

The problem with the current implementation is that it only changes
the routing if the msi entry goes from masked to unmasked state.

Linux does not mask the entries on affinity changes and never did,
neither for MSI nor for MSI-X.

I know it's probably not according to the spec, but we can't fix that
retroactively.

Thanks,

	tglx

  parent reply	other threads:[~2012-05-24 21:39 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-24 17:02 [PATCH 1/2] Remove kvm_commit_irq_routes from error messages Richard Weinberger
2012-05-24 17:02 ` [PATCH 2/2] Device assignment: Fix MSI IRQ affinity setting Richard Weinberger
2012-05-24 18:20   ` Alex Williamson
     [not found]     ` <CAEMbtc+ycsC6u=CZ_Yg6C=WV=VqjA2uEDM5KWPM_7n3sZh_9Pw@mail.gmail.com>
2012-05-24 19:27       ` Richard Weinberger
2012-05-24 21:39     ` Thomas Gleixner [this message]
2012-05-24 21:53       ` Jan Kiszka
2012-05-24 22:11         ` Alex Williamson
2012-05-24 23:01           ` Thomas Gleixner
2012-05-24 23:23             ` Alex Williamson
2012-05-24 23:56               ` Thomas Gleixner
2012-05-25  2:37                 ` Jan Kiszka
2012-05-24 22:17         ` Michael S. Tsirkin
2012-05-24 23:06           ` Thomas Gleixner
2012-05-24 23:19             ` Thomas Gleixner
2012-05-24 22:05       ` Alex Williamson
2012-05-24 20:47   ` Jan Kiszka

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=alpine.LFD.2.02.1205242323230.3231@ionos \
    --to=tglx@linutronix.de \
    --cc=alex.williamson@redhat.com \
    --cc=avi@redhat.com \
    --cc=bhelgaas@google.com \
    --cc=kvm@vger.kernel.org \
    --cc=mtosatti@redhat.com \
    --cc=richard@nod.at \
    /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