[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH] ACPI DSDT: Make control method `IQCR` serialize
From: |
Laszlo Ersek |
Subject: |
Re: [Qemu-devel] [PATCH] ACPI DSDT: Make control method `IQCR` serialized |
Date: |
Thu, 14 Nov 2013 15:44:47 +0100 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20131028 Thunderbird/17.0.10 |
On 11/14/13 13:16, Michael S. Tsirkin wrote:
> Forward-port the following commit from seabios:
>
> commit 995bbeef78b338370f426bf8d0399038c3fa259c
> Author: Paul Menzel <address@hidden>
> 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 <address@hidden>
>
> Reported-by: Marcel Apfelbaum <address@hidden>
> Signed-off-by: Michael S. Tsirkin <address@hidden>
> ---
> 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 <address@hidden>