From: Laszlo Ersek <lersek@redhat.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Marcel Apfelbaum <marcel.a@redhat.com>,
Hu Tao <hutao@cn.fujitsu.com>,
qemu-devel@nongnu.org, Gerd Hoffmann <kraxel@redhat.com>,
Anthony Liguori <aliguori@amazon.com>,
Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>,
Igor Mammedov <imammedo@redhat.com>,
Paul Menzel <paulepanter@users.sourceforge.net>
Subject: Re: [Qemu-devel] [PATCH] ACPI DSDT: Make control method `IQCR` serialized
Date: Thu, 14 Nov 2013 15:44:47 +0100 [thread overview]
Message-ID: <5284E1DF.5030404@redhat.com> (raw)
In-Reply-To: <20131114121609.GA4997@redhat.com>
On 11/14/13 13:16, Michael S. Tsirkin wrote:
> Forward-port the following commit from seabios:
>
> commit 995bbeef78b338370f426bf8d0399038c3fa259c
> Author: Paul Menzel <paulepanter@users.sourceforge.net>
> Date: Thu Oct 3 11:30:52 2013 +0200
>
> The ASL Optimizing Compiler version 20130823-32 [Sep 11 2013] issues the
> following warning.
>
> $ make
> […]
> Compiling IASL out/src/fw/acpi-dsdt.hex
> out/src/fw/acpi-dsdt.dsl.i 360: Method(IQCR, 1, NotSerialized) {
> Remark 2120 - ^ Control Method should be made Serialized (due to creation of named objects within)
> […]
> ASL Input: out/src/fw/acpi-dsdt.dsl.i - 475 lines, 19181 bytes, 316 keywords
> AML Output: out/src/fw/acpi-dsdt.aml - 4407 bytes, 159 named objects, 157 executable opcodes
> Listing File: out/src/fw/acpi-dsdt.lst - 143715 bytes
> Hex Dump: out/src/fw/acpi-dsdt.hex - 41661 bytes
>
> Compilation complete. 0 Errors, 0 Warnings, 1 Remarks, 246 Optimizations
> […]
>
> After changing the parameter from `NotSerialized` to `Serialized`, the
> remark is indeed gone and there is no size change.
>
> The remark was added in ACPICA version 20130517 [1] and gives the
> following explanation.
>
> If a thread blocks within the method for any reason, and another thread
> enters the method, the method will fail because an attempt will be
> made to create the same (named) object twice.
>
> In this case, issue a remark that the method should be marked
> serialized. ACPICA BZ 909.
>
> [1] https://github.com/acpica/acpica/commit/ba84d0fc18ba910a47a3f71c68a43543c06e6831
>
> Signed-off-by: Paul Menzel <paulepanter@users.sourceforge.net>
>
> Reported-by: Marcel Apfelbaum <marcel.a@redhat.com>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
> hw/i386/acpi-dsdt.dsl | 2 +-
> hw/i386/acpi-dsdt.hex.generated | 4 ++--
> hw/i386/q35-acpi-dsdt.dsl | 2 +-
> hw/i386/q35-acpi-dsdt.hex.generated | 4 ++--
> 4 files changed, 6 insertions(+), 6 deletions(-)
The analysis / evolution of the iasl change
<https://bugs.acpica.org/show_bug.cgi?id=909> is instrumental.
The patch looks good to me (although you could sell me anything in the
binary part).
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
prev parent reply other threads:[~2013-11-14 14:42 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-14 12:16 [Qemu-devel] [PATCH] ACPI DSDT: Make control method `IQCR` serialized Michael S. Tsirkin
2013-11-14 13:37 ` Marcel Apfelbaum
2013-11-14 14:44 ` Laszlo Ersek [this message]
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=5284E1DF.5030404@redhat.com \
--to=lersek@redhat.com \
--cc=aliguori@amazon.com \
--cc=hutao@cn.fujitsu.com \
--cc=imammedo@redhat.com \
--cc=kaneshige.kenji@jp.fujitsu.com \
--cc=kraxel@redhat.com \
--cc=marcel.a@redhat.com \
--cc=mst@redhat.com \
--cc=paulepanter@users.sourceforge.net \
--cc=qemu-devel@nongnu.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).