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* [PATCH] virtio-mem: introduce VIRTIO_MEM_F_PERSISTENT_SUSPEND
@ 2024-08-09 14:03 Juraj Marcin
  2024-08-21 18:31 ` David Hildenbrand
  2024-10-07  8:17 ` David Hildenbrand
  0 siblings, 2 replies; 6+ messages in thread
From: Juraj Marcin @ 2024-08-09 14:03 UTC (permalink / raw)
  To: virtio-comment; +Cc: Juraj Marcin

Before, the behavior while suspending to a deep sleep state and waking
up was not specified. For example, in x86 QEMU VM all devices receive a
reset request during wake-up. This would lead to unplugging of all the
plugged memory blocks. Due to this, suspending is disallowed in the
Linux Kernel, when plugged memory is present and
VIRTIO_MEM_F_PERSISTENT_SUSPEND feature flag is not advertised by the
virtio-mem device.

This new flag should signal to the guest driver, that the device can
correctly suspend to a deep sleep state and then wake up without
disrupting the plugged memory blocks. This feature flag is already
supported in the Linux Kernel [1] and should be soon also supported in
QEMU [2].

[1]: https://lore.kernel.org/all/20240318120645.105664-1-david@redhat.com/
[2]: https://lore.kernel.org/all/20240806160756.182524-1-jmarcin@redhat.com/

Signed-off-by: Juraj Marcin <jmarcin@redhat.com>
---
 device-types/mem/description.tex | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/device-types/mem/description.tex b/device-types/mem/description.tex
index 0a6d558..5bff24c 100644
--- a/device-types/mem/description.tex
+++ b/device-types/mem/description.tex
@@ -60,6 +60,8 @@ \subsection{Feature bits}\label{sec:Device Types / Memory Device / Feature bits}
 access unplugged memory. \footnote{On platforms with memory properties that
 might get modified implicitly on memory access, this feature is expected to
 be offered by the device.}
+\item[VIRTIO_MEM_F_PERSISTENT_SUSPEND (2)] The driver can allow the guest
+system to enter suspended state (deep sleep, suspend-to-RAM).
 \end{description}
 
 \subsection{Device configuration layout}\label{sec:Device Types / Memory Device / Device configuration layout}
@@ -174,6 +176,9 @@ \subsection{Device Initialization}\label{Device Types / Memory Device / Device I
 The device MUST NOT modify memory or memory properties of plugged memory
 blocks during device reset.
 
+The device SHOULD offer VIRTIO_MEM_F_PERSISTENT_SUSPEND if the platform
+supports suspending (deep sleep, suspend-to-RAM) with plugged memory blocks.
+
 \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Operation}
 
 The device notifies the driver about the amount of memory the device wants
@@ -268,6 +273,9 @@ \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Op
 memory blocks to unplug them, or it would not be able to make use of
 unplugged memory blocks after plugging them (e.g., alignment).
 
+If VIRTIO_MEM_F_PERSISTENT_SUSPEND has not been negotiated, the driver MUST NOT
+allow the guest system to enter a suspended state (deep sleep, suspend-to-RAM).
+
 \devicenormative{\subsubsection}{Device Operation}{Device Types / Memory Device / Device Operation}
 
 The device MUST provide the exact same memory properties with the exact same
@@ -293,6 +301,10 @@ \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Op
 
 The device SHOULD unplug all memory blocks during system resets.
 
+If VIRTIO_MEM_F_PERSISTENT_SUSPEND has been negotiated, the device MUST NOT not
+change the state of memory blocks when suspending or when waking up from
+suspended state (deep sleep, suspend-to-RAM).
+
 \subsubsection{PLUG request}\label{sec:Device Types / Memory Device / Device Operation / PLUG request}
 
 Request to plug consecutive memory blocks that are currently unplugged.
-- 
2.45.2


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH] virtio-mem: introduce VIRTIO_MEM_F_PERSISTENT_SUSPEND
  2024-08-09 14:03 [PATCH] virtio-mem: introduce VIRTIO_MEM_F_PERSISTENT_SUSPEND Juraj Marcin
@ 2024-08-21 18:31 ` David Hildenbrand
  2024-10-07  8:17 ` David Hildenbrand
  1 sibling, 0 replies; 6+ messages in thread
From: David Hildenbrand @ 2024-08-21 18:31 UTC (permalink / raw)
  To: Juraj Marcin, virtio-comment

On 09.08.24 16:03, Juraj Marcin wrote:
> Before, the behavior while suspending to a deep sleep state and waking
> up was not specified. For example, in x86 QEMU VM all devices receive a
> reset request during wake-up. This would lead to unplugging of all the
> plugged memory blocks. Due to this, suspending is disallowed in the
> Linux Kernel, when plugged memory is present and
> VIRTIO_MEM_F_PERSISTENT_SUSPEND feature flag is not advertised by the
> virtio-mem device.
> 
> This new flag should signal to the guest driver, that the device can
> correctly suspend to a deep sleep state and then wake up without
> disrupting the plugged memory blocks. This feature flag is already
> supported in the Linux Kernel [1] and should be soon also supported in
> QEMU [2].
> 
> [1]: https://lore.kernel.org/all/20240318120645.105664-1-david@redhat.com/
> [2]: https://lore.kernel.org/all/20240806160756.182524-1-jmarcin@redhat.com/
> 
> Signed-off-by: Juraj Marcin <jmarcin@redhat.com>
> ---
>   device-types/mem/description.tex | 12 ++++++++++++
>   1 file changed, 12 insertions(+)
> 
> diff --git a/device-types/mem/description.tex b/device-types/mem/description.tex
> index 0a6d558..5bff24c 100644
> --- a/device-types/mem/description.tex
> +++ b/device-types/mem/description.tex
> @@ -60,6 +60,8 @@ \subsection{Feature bits}\label{sec:Device Types / Memory Device / Feature bits}
>   access unplugged memory. \footnote{On platforms with memory properties that
>   might get modified implicitly on memory access, this feature is expected to
>   be offered by the device.}
> +\item[VIRTIO_MEM_F_PERSISTENT_SUSPEND (2)] The driver can allow the guest
> +system to enter suspended state (deep sleep, suspend-to-RAM).
>   \end{description}
>   
>   \subsection{Device configuration layout}\label{sec:Device Types / Memory Device / Device configuration layout}
> @@ -174,6 +176,9 @@ \subsection{Device Initialization}\label{Device Types / Memory Device / Device I
>   The device MUST NOT modify memory or memory properties of plugged memory
>   blocks during device reset.
>   
> +The device SHOULD offer VIRTIO_MEM_F_PERSISTENT_SUSPEND if the platform
> +supports suspending (deep sleep, suspend-to-RAM) with plugged memory blocks.
> +
>   \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Operation}
>   
>   The device notifies the driver about the amount of memory the device wants
> @@ -268,6 +273,9 @@ \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Op
>   memory blocks to unplug them, or it would not be able to make use of
>   unplugged memory blocks after plugging them (e.g., alignment).
>   
> +If VIRTIO_MEM_F_PERSISTENT_SUSPEND has not been negotiated, the driver MUST NOT
> +allow the guest system to enter a suspended state (deep sleep, suspend-to-RAM).
> +
>   \devicenormative{\subsubsection}{Device Operation}{Device Types / Memory Device / Device Operation}
>   
>   The device MUST provide the exact same memory properties with the exact same
> @@ -293,6 +301,10 @@ \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Op
>   
>   The device SHOULD unplug all memory blocks during system resets.
>   
> +If VIRTIO_MEM_F_PERSISTENT_SUSPEND has been negotiated, the device MUST NOT not
> +change the state of memory blocks when suspending or when waking up from
> +suspended state (deep sleep, suspend-to-RAM).
> +
>   \subsubsection{PLUG request}\label{sec:Device Types / Memory Device / Device Operation / PLUG request}
>   
>   Request to plug consecutive memory blocks that are currently unplugged.

All sounds correct to me, thanks!

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Cheers,

David / dhildenb


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] virtio-mem: introduce VIRTIO_MEM_F_PERSISTENT_SUSPEND
  2024-08-09 14:03 [PATCH] virtio-mem: introduce VIRTIO_MEM_F_PERSISTENT_SUSPEND Juraj Marcin
  2024-08-21 18:31 ` David Hildenbrand
@ 2024-10-07  8:17 ` David Hildenbrand
  2024-10-07 14:22   ` Matias Ezequiel Vara Larsen
  1 sibling, 1 reply; 6+ messages in thread
From: David Hildenbrand @ 2024-10-07  8:17 UTC (permalink / raw)
  To: Juraj Marcin, virtio-comment; +Cc: Cornelia Huck

On 09.08.24 16:03, Juraj Marcin wrote:
> Before, the behavior while suspending to a deep sleep state and waking
> up was not specified. For example, in x86 QEMU VM all devices receive a
> reset request during wake-up. This would lead to unplugging of all the
> plugged memory blocks. Due to this, suspending is disallowed in the
> Linux Kernel, when plugged memory is present and
> VIRTIO_MEM_F_PERSISTENT_SUSPEND feature flag is not advertised by the
> virtio-mem device.
> 
> This new flag should signal to the guest driver, that the device can
> correctly suspend to a deep sleep state and then wake up without
> disrupting the plugged memory blocks. This feature flag is already
> supported in the Linux Kernel [1] and should be soon also supported in
> QEMU [2].
> 
> [1]: https://lore.kernel.org/all/20240318120645.105664-1-david@redhat.com/
> [2]: https://lore.kernel.org/all/20240806160756.182524-1-jmarcin@redhat.com/
> 
> Signed-off-by: Juraj Marcin <jmarcin@redhat.com>
> ---
>   device-types/mem/description.tex | 12 ++++++++++++
>   1 file changed, 12 insertions(+)
> 
> diff --git a/device-types/mem/description.tex b/device-types/mem/description.tex
> index 0a6d558..5bff24c 100644
> --- a/device-types/mem/description.tex
> +++ b/device-types/mem/description.tex
> @@ -60,6 +60,8 @@ \subsection{Feature bits}\label{sec:Device Types / Memory Device / Feature bits}
>   access unplugged memory. \footnote{On platforms with memory properties that
>   might get modified implicitly on memory access, this feature is expected to
>   be offered by the device.}
> +\item[VIRTIO_MEM_F_PERSISTENT_SUSPEND (2)] The driver can allow the guest
> +system to enter suspended state (deep sleep, suspend-to-RAM).
>   \end{description}
>   
>   \subsection{Device configuration layout}\label{sec:Device Types / Memory Device / Device configuration layout}
> @@ -174,6 +176,9 @@ \subsection{Device Initialization}\label{Device Types / Memory Device / Device I
>   The device MUST NOT modify memory or memory properties of plugged memory
>   blocks during device reset.
>   
> +The device SHOULD offer VIRTIO_MEM_F_PERSISTENT_SUSPEND if the platform
> +supports suspending (deep sleep, suspend-to-RAM) with plugged memory blocks.
> +
>   \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Operation}
>   
>   The device notifies the driver about the amount of memory the device wants
> @@ -268,6 +273,9 @@ \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Op
>   memory blocks to unplug them, or it would not be able to make use of
>   unplugged memory blocks after plugging them (e.g., alignment).
>   
> +If VIRTIO_MEM_F_PERSISTENT_SUSPEND has not been negotiated, the driver MUST NOT
> +allow the guest system to enter a suspended state (deep sleep, suspend-to-RAM).
> +
>   \devicenormative{\subsubsection}{Device Operation}{Device Types / Memory Device / Device Operation}
>   
>   The device MUST provide the exact same memory properties with the exact same
> @@ -293,6 +301,10 @@ \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Op
>   
>   The device SHOULD unplug all memory blocks during system resets.
>   
> +If VIRTIO_MEM_F_PERSISTENT_SUSPEND has been negotiated, the device MUST NOT not
> +change the state of memory blocks when suspending or when waking up from
> +suspended state (deep sleep, suspend-to-RAM).
> +
>   \subsubsection{PLUG request}\label{sec:Device Types / Memory Device / Device Operation / PLUG request}
>   
>   Request to plug consecutive memory blocks that are currently unplugged.

The kernel and QEMU part is upstream. A second pair of eyes would be 
great :)

-- 
Cheers,

David / dhildenb


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] virtio-mem: introduce VIRTIO_MEM_F_PERSISTENT_SUSPEND
  2024-10-07  8:17 ` David Hildenbrand
@ 2024-10-07 14:22   ` Matias Ezequiel Vara Larsen
  2024-10-08 13:14     ` David Hildenbrand
  0 siblings, 1 reply; 6+ messages in thread
From: Matias Ezequiel Vara Larsen @ 2024-10-07 14:22 UTC (permalink / raw)
  To: David Hildenbrand; +Cc: Juraj Marcin, virtio-comment, Cornelia Huck

On Mon, Oct 07, 2024 at 10:17:23AM +0200, David Hildenbrand wrote:
> On 09.08.24 16:03, Juraj Marcin wrote:
> > Before, the behavior while suspending to a deep sleep state and waking
> > up was not specified. For example, in x86 QEMU VM all devices receive a
> > reset request during wake-up. This would lead to unplugging of all the
> > plugged memory blocks. Due to this, suspending is disallowed in the
> > Linux Kernel, when plugged memory is present and
> > VIRTIO_MEM_F_PERSISTENT_SUSPEND feature flag is not advertised by the
> > virtio-mem device.
> > 
> > This new flag should signal to the guest driver, that the device can
> > correctly suspend to a deep sleep state and then wake up without
> > disrupting the plugged memory blocks. This feature flag is already
> > supported in the Linux Kernel [1] and should be soon also supported in
> > QEMU [2].
> > 
> > [1]: https://lore.kernel.org/all/20240318120645.105664-1-david@redhat.com/
> > [2]: https://lore.kernel.org/all/20240806160756.182524-1-jmarcin@redhat.com/
> > 
> > Signed-off-by: Juraj Marcin <jmarcin@redhat.com>
> > ---
> >   device-types/mem/description.tex | 12 ++++++++++++
> >   1 file changed, 12 insertions(+)
> > 
> > diff --git a/device-types/mem/description.tex b/device-types/mem/description.tex
> > index 0a6d558..5bff24c 100644
> > --- a/device-types/mem/description.tex
> > +++ b/device-types/mem/description.tex
> > @@ -60,6 +60,8 @@ \subsection{Feature bits}\label{sec:Device Types / Memory Device / Feature bits}
> >   access unplugged memory. \footnote{On platforms with memory properties that
> >   might get modified implicitly on memory access, this feature is expected to
> >   be offered by the device.}
> > +\item[VIRTIO_MEM_F_PERSISTENT_SUSPEND (2)] The driver can allow the guest
> > +system to enter suspended state (deep sleep, suspend-to-RAM).
> >   \end{description}
> >   \subsection{Device configuration layout}\label{sec:Device Types / Memory Device / Device configuration layout}
> > @@ -174,6 +176,9 @@ \subsection{Device Initialization}\label{Device Types / Memory Device / Device I
> >   The device MUST NOT modify memory or memory properties of plugged memory
> >   blocks during device reset.
> > +The device SHOULD offer VIRTIO_MEM_F_PERSISTENT_SUSPEND if the platform
> > +supports suspending (deep sleep, suspend-to-RAM) with plugged memory blocks.
> > +
> >   \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Operation}
> >   The device notifies the driver about the amount of memory the device wants
> > @@ -268,6 +273,9 @@ \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Op
> >   memory blocks to unplug them, or it would not be able to make use of
> >   unplugged memory blocks after plugging them (e.g., alignment).
> > +If VIRTIO_MEM_F_PERSISTENT_SUSPEND has not been negotiated, the driver MUST NOT
> > +allow the guest system to enter a suspended state (deep sleep, suspend-to-RAM).

I think `guest system` could be simply `guest` but I do not have a
strong opinion about it.

> > +
> >   \devicenormative{\subsubsection}{Device Operation}{Device Types / Memory Device / Device Operation}
> >   The device MUST provide the exact same memory properties with the exact same
> > @@ -293,6 +301,10 @@ \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Op
> >   The device SHOULD unplug all memory blocks during system resets.
> > +If VIRTIO_MEM_F_PERSISTENT_SUSPEND has been negotiated, the device MUST NOT not
> > +change the state of memory blocks when suspending or when waking up from
> > +suspended state (deep sleep, suspend-to-RAM).
> > +
> >   \subsubsection{PLUG request}\label{sec:Device Types / Memory Device / Device Operation / PLUG request}
> >   Request to plug consecutive memory blocks that are currently unplugged.
> 
> The kernel and QEMU part is upstream. A second pair of eyes would be great
> :)
> 

Reviewed-by: Matias Ezequiel Vara Larsen <mvaralar@redhat.com>

Matias


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] virtio-mem: introduce VIRTIO_MEM_F_PERSISTENT_SUSPEND
  2024-10-07 14:22   ` Matias Ezequiel Vara Larsen
@ 2024-10-08 13:14     ` David Hildenbrand
  2024-10-09  7:45       ` Juraj Marcin
  0 siblings, 1 reply; 6+ messages in thread
From: David Hildenbrand @ 2024-10-08 13:14 UTC (permalink / raw)
  To: Matias Ezequiel Vara Larsen; +Cc: Juraj Marcin, virtio-comment, Cornelia Huck

On 07.10.24 16:22, Matias Ezequiel Vara Larsen wrote:
> On Mon, Oct 07, 2024 at 10:17:23AM +0200, David Hildenbrand wrote:
>> On 09.08.24 16:03, Juraj Marcin wrote:
>>> Before, the behavior while suspending to a deep sleep state and waking
>>> up was not specified. For example, in x86 QEMU VM all devices receive a
>>> reset request during wake-up. This would lead to unplugging of all the
>>> plugged memory blocks. Due to this, suspending is disallowed in the
>>> Linux Kernel, when plugged memory is present and
>>> VIRTIO_MEM_F_PERSISTENT_SUSPEND feature flag is not advertised by the
>>> virtio-mem device.
>>>
>>> This new flag should signal to the guest driver, that the device can
>>> correctly suspend to a deep sleep state and then wake up without
>>> disrupting the plugged memory blocks. This feature flag is already
>>> supported in the Linux Kernel [1] and should be soon also supported in
>>> QEMU [2].
>>>
>>> [1]: https://lore.kernel.org/all/20240318120645.105664-1-david@redhat.com/
>>> [2]: https://lore.kernel.org/all/20240806160756.182524-1-jmarcin@redhat.com/
>>>
>>> Signed-off-by: Juraj Marcin <jmarcin@redhat.com>
>>> ---
>>>    device-types/mem/description.tex | 12 ++++++++++++
>>>    1 file changed, 12 insertions(+)
>>>
>>> diff --git a/device-types/mem/description.tex b/device-types/mem/description.tex
>>> index 0a6d558..5bff24c 100644
>>> --- a/device-types/mem/description.tex
>>> +++ b/device-types/mem/description.tex
>>> @@ -60,6 +60,8 @@ \subsection{Feature bits}\label{sec:Device Types / Memory Device / Feature bits}
>>>    access unplugged memory. \footnote{On platforms with memory properties that
>>>    might get modified implicitly on memory access, this feature is expected to
>>>    be offered by the device.}
>>> +\item[VIRTIO_MEM_F_PERSISTENT_SUSPEND (2)] The driver can allow the guest
>>> +system to enter suspended state (deep sleep, suspend-to-RAM).
>>>    \end{description}
>>>    \subsection{Device configuration layout}\label{sec:Device Types / Memory Device / Device configuration layout}
>>> @@ -174,6 +176,9 @@ \subsection{Device Initialization}\label{Device Types / Memory Device / Device I
>>>    The device MUST NOT modify memory or memory properties of plugged memory
>>>    blocks during device reset.
>>> +The device SHOULD offer VIRTIO_MEM_F_PERSISTENT_SUSPEND if the platform
>>> +supports suspending (deep sleep, suspend-to-RAM) with plugged memory blocks.
>>> +
>>>    \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Operation}
>>>    The device notifies the driver about the amount of memory the device wants
>>> @@ -268,6 +273,9 @@ \subsection{Device Operation}\label{sec:Device Types / Memory Device / Device Op
>>>    memory blocks to unplug them, or it would not be able to make use of
>>>    unplugged memory blocks after plugging them (e.g., alignment).
>>> +If VIRTIO_MEM_F_PERSISTENT_SUSPEND has not been negotiated, the driver MUST NOT
>>> +allow the guest system to enter a suspended state (deep sleep, suspend-to-RAM).
> 
> I think `guest system` could be simply `guest` but I do not have a
> strong opinion about it.

Makes sense. @Juraj, can you respin with that adjusted?

I'll open an issue afterwards and request a vote.

-- 
Cheers,

David / dhildenb


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] virtio-mem: introduce VIRTIO_MEM_F_PERSISTENT_SUSPEND
  2024-10-08 13:14     ` David Hildenbrand
@ 2024-10-09  7:45       ` Juraj Marcin
  0 siblings, 0 replies; 6+ messages in thread
From: Juraj Marcin @ 2024-10-09  7:45 UTC (permalink / raw)
  To: David Hildenbrand
  Cc: Matias Ezequiel Vara Larsen, virtio-comment, Cornelia Huck

[-- Attachment #1: Type: text/plain, Size: 3563 bytes --]

On Tue, Oct 8, 2024, 15:14 David Hildenbrand <david@redhat.com> wrote:

> On 07.10.24 16:22, Matias Ezequiel Vara Larsen wrote:
> > On Mon, Oct 07, 2024 at 10:17:23AM +0200, David Hildenbrand wrote:
> >> On 09.08.24 16:03, Juraj Marcin wrote:
> >>> Before, the behavior while suspending to a deep sleep state and waking
> >>> up was not specified. For example, in x86 QEMU VM all devices receive a
> >>> reset request during wake-up. This would lead to unplugging of all the
> >>> plugged memory blocks. Due to this, suspending is disallowed in the
> >>> Linux Kernel, when plugged memory is present and
> >>> VIRTIO_MEM_F_PERSISTENT_SUSPEND feature flag is not advertised by the
> >>> virtio-mem device.
> >>>
> >>> This new flag should signal to the guest driver, that the device can
> >>> correctly suspend to a deep sleep state and then wake up without
> >>> disrupting the plugged memory blocks. This feature flag is already
> >>> supported in the Linux Kernel [1] and should be soon also supported in
> >>> QEMU [2].
> >>>
> >>> [1]:
> https://lore.kernel.org/all/20240318120645.105664-1-david@redhat.com/
> >>> [2]:
> https://lore.kernel.org/all/20240806160756.182524-1-jmarcin@redhat.com/
> >>>
> >>> Signed-off-by: Juraj Marcin <jmarcin@redhat.com>
> >>> ---
> >>>    device-types/mem/description.tex | 12 ++++++++++++
> >>>    1 file changed, 12 insertions(+)
> >>>
> >>> diff --git a/device-types/mem/description.tex
> b/device-types/mem/description.tex
> >>> index 0a6d558..5bff24c 100644
> >>> --- a/device-types/mem/description.tex
> >>> +++ b/device-types/mem/description.tex
> >>> @@ -60,6 +60,8 @@ \subsection{Feature bits}\label{sec:Device Types /
> Memory Device / Feature bits}
> >>>    access unplugged memory. \footnote{On platforms with memory
> properties that
> >>>    might get modified implicitly on memory access, this feature is
> expected to
> >>>    be offered by the device.}
> >>> +\item[VIRTIO_MEM_F_PERSISTENT_SUSPEND (2)] The driver can allow the
> guest
> >>> +system to enter suspended state (deep sleep, suspend-to-RAM).
> >>>    \end{description}
> >>>    \subsection{Device configuration layout}\label{sec:Device Types /
> Memory Device / Device configuration layout}
> >>> @@ -174,6 +176,9 @@ \subsection{Device Initialization}\label{Device
> Types / Memory Device / Device I
> >>>    The device MUST NOT modify memory or memory properties of plugged
> memory
> >>>    blocks during device reset.
> >>> +The device SHOULD offer VIRTIO_MEM_F_PERSISTENT_SUSPEND if the
> platform
> >>> +supports suspending (deep sleep, suspend-to-RAM) with plugged memory
> blocks.
> >>> +
> >>>    \subsection{Device Operation}\label{sec:Device Types / Memory
> Device / Device Operation}
> >>>    The device notifies the driver about the amount of memory the
> device wants
> >>> @@ -268,6 +273,9 @@ \subsection{Device Operation}\label{sec:Device
> Types / Memory Device / Device Op
> >>>    memory blocks to unplug them, or it would not be able to make use of
> >>>    unplugged memory blocks after plugging them (e.g., alignment).
> >>> +If VIRTIO_MEM_F_PERSISTENT_SUSPEND has not been negotiated, the
> driver MUST NOT
> >>> +allow the guest system to enter a suspended state (deep sleep,
> suspend-to-RAM).
> >
> > I think `guest system` could be simply `guest` but I do not have a
> > strong opinion about it.
>
> Makes sense. @Juraj, can you respin with that adjusted?
>

Sure thing. I will update it and respin it shortly.

Thanks!



> I'll open an issue afterwards and request a vote.
>
> --
> Cheers,
>
> David / dhildenb
>

>

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^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2024-10-09  7:47 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-08-09 14:03 [PATCH] virtio-mem: introduce VIRTIO_MEM_F_PERSISTENT_SUSPEND Juraj Marcin
2024-08-21 18:31 ` David Hildenbrand
2024-10-07  8:17 ` David Hildenbrand
2024-10-07 14:22   ` Matias Ezequiel Vara Larsen
2024-10-08 13:14     ` David Hildenbrand
2024-10-09  7:45       ` Juraj Marcin

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