5:08 a.m.
libvirt documentation for channels with type 'spicevmc' says that the
'target' child node has:
"an optional attribute name controls how the guest will have access
to the channel, and defaults to name='com.redhat.spice.0'."
However, this default value is never set in libvirt code base,
there's only a check in qemu_command.c to error out if the name
attribute doesn't have the expected value (if it's set).
This commit sets a default target name for spicevmc channels during
the domain configuration parsing so that the code agrees with the
documentation.
---
src/conf/domain_conf.c | 7 +++++++
1 files changed, 7 insertions(+), 0 deletions(-)
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index d5def1c..9012462 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -5218,6 +5218,13 @@ virDomainChrDefParseXML(virCapsPtr caps,
goto error;
} else {
def->source.data.spicevmc = VIR_DOMAIN_CHR_SPICEVMC_VDAGENT;
+ if (!def->target.name) {
+ def->target.name = strdup("com.redhat.spice.0");
+ if (!def->target.name) {
+ virReportOOMError();
+ goto error;
+ }
+ }
}
}
--
1.7.7.6
11:02 a.m.
On 03/23/2012 04:08 AM, Christophe Fergeau wrote:
libvirt documentation for channels with type 'spicevmc' says
that the
'target' child node has:
"an optional attribute name controls how the guest will have access
to the channel, and defaults to name='com.redhat.spice.0'."
However, this default value is never set in libvirt code base,
there's only a check in qemu_command.c to error out if the name
attribute doesn't have the expected value (if it's set).
This commit sets a default target name for spicevmc channels during
the domain configuration parsing so that the code agrees with the
documentation.
---
src/conf/domain_conf.c | 7 +++++++
1 files changed, 7 insertions(+), 0 deletions(-)
ACK, and okay to push before 0.9.11.
} else {
def->source.data.spicevmc = VIR_DOMAIN_CHR_SPICEVMC_VDAGENT;
+ if (!def->target.name) {
+ def->target.name = strdup("com.redhat.spice.0");
+ if (!def->target.name) {
+ virReportOOMError();
+ goto error;
+ }
+ }
}
}
--
Eric Blake eblake(a)redhat.com +1-919-301-3266
Libvirt virtualization library http://libvirt.org
11:34 a.m.
On Wed, Mar 28, 2012 at 10:02:40AM -0600, Eric Blake wrote:
On 03/23/2012 04:08 AM, Christophe Fergeau wrote:
> libvirt documentation for channels with type 'spicevmc' says that the
> 'target' child node has:
> "an optional attribute name controls how the guest will have access
> to the channel, and defaults to name='com.redhat.spice.0'."
>
> However, this default value is never set in libvirt code base,
> there's only a check in qemu_command.c to error out if the name
> attribute doesn't have the expected value (if it's set).
>
> This commit sets a default target name for spicevmc channels during
> the domain configuration parsing so that the code agrees with the
> documentation.
> ---
> src/conf/domain_conf.c | 7 +++++++
> 1 files changed, 7 insertions(+), 0 deletions(-)
ACK, and okay to push before 0.9.11.
Thanks, pushed.
Christophe
2:20 p.m.
On 03/28/2012 12:02 PM, Eric Blake wrote:
On 03/23/2012 04:08 AM, Christophe Fergeau wrote:
> libvirt documentation for channels with type 'spicevmc' says that the
> 'target' child node has:
> "an optional attribute name controls how the guest will have access
> to the channel, and defaults to name='com.redhat.spice.0'."
>
> However, this default value is never set in libvirt code base,
> there's only a check in qemu_command.c to error out if the name
> attribute doesn't have the expected value (if it's set).
>
> This commit sets a default target name for spicevmc channels during
> the domain configuration parsing so that the code agrees with the
> documentation.
> ---
> src/conf/domain_conf.c | 7 +++++++
> 1 files changed, 7 insertions(+), 0 deletions(-)
ACK, and okay to push before 0.9.11.
> } else {
> def->source.data.spicevmc = VIR_DOMAIN_CHR_SPICEVMC_VDAGENT;
> + if (!def->target.name) {
> + def->target.name = strdup("com.redhat.spice.0");
> + if (!def->target.name) {
> + virReportOOMError();
> + goto error;
> + }
> + }
> }
> }
>
I know I'm a bit late to the party (I missed your mail before), but
would it have been possible to do the "default" processing in the caller
rather than in the parsing function itself?
Setting it here means that if the default changes, previously defined
guests will be stuck with the old default (since it will be encoded into
re-formatted XML saved to disk), and assigning default values in parsing
functions has in the past led to trouble (e.g. the fact that
virDomainNetDefParseXML adds a mac address when one isn't specified
caused trouble because parsing the same XML twice gave difference
results; that particular problem wouldn't happen here, obviously).
4:52 a.m.
On Wed, Mar 28, 2012 at 03:20:45PM -0400, Laine Stump wrote:
I know I'm a bit late to the party (I missed your mail before),
but
would it have been possible to do the "default" processing in the caller
rather than in the parsing function itself?
I cannot disagree since I was not sure at all that this was the right place
for setting defaults, I should have mentioned this explicitly when sending
the patch.. Who is "the caller" exactly in this case?
Thanks,
Christophe
4:10 p.m.
On 03/29/2012 05:52 AM, Christophe Fergeau wrote:
On Wed, Mar 28, 2012 at 03:20:45PM -0400, Laine Stump wrote:
> I know I'm a bit late to the party (I missed your mail before), but
> would it have been possible to do the "default" processing in the caller
> rather than in the parsing function itself?
I cannot disagree since I was not sure at all that this was the right place
for setting defaults, I should have mentioned this explicitly when sending
the patch.. Who is "the caller" exactly in this case?
I'm not previously familiar with this attribute, but it looks like the
only place it's used is in qemuBuildVirtioSerialPortDevStr, where it
does the following:
1) if it's set, and doesn't == "com.redhat.spice.0" it logs an error
and
fails
2) if it's set, the option ",name=com.redhat.spice.0" is added to the
device string.
So it looks like you could get the same effect by changing that last bit
to either add the contents of dev->target.name, or if that's NULL,
"com.redhat.spice.0".
In this particular case I don't know if it's going to make any
difference in practice; I'm just always wary of parser code that
modifies the output such that it doesn't mirror the input. (One way of
thinking about it is that if you were to set everything in an object,
then do a Format/Parse roundtrip, the results would be different. That's
going to end up being the case anyway because there's already so much
existing parse code that commits this sin (my opinion), but I think it's
good to reduce the amount of this type behavior as much as possible.
Does anyone with more experience with the libvirt spice code have any
opinion on whether it makes any difference if we add in the default in
the parsing function or just when we build the commandline? danpb?
4:21 p.m.
On 03/29/2012 03:10 PM, Laine Stump wrote:
2) if it's set, the option ",name=com.redhat.spice.0"
is added to the
device string.
So it looks like you could get the same effect by changing that last bit
to either add the contents of dev->target.name, or if that's NULL,
"com.redhat.spice.0".
I'd be fine with a patch along these lines that moves the default out of
domain_conf.c and into the command line generator.
Does anyone with more experience with the libvirt spice code have
any
opinion on whether it makes any difference if we add in the default in
the parsing function or just when we build the commandline? danpb?
Delaying the default until command line generation should be just fine.
--
Eric Blake eblake(a)redhat.com +1-919-301-3266
Libvirt virtualization library http://libvirt.org
2:50 a.m.
New subject: [libvirt] [PATCH] qemu: set default name for SPICE agent channel when generating command
commit b0e2bb33 set a default value for the SPICE agent channel by
inserting it during parsing of the channel XML. That method of setting
a default is problematic because it makes a format/parse roundtrip
unclean, and experience with setting other values as a side effect of
parsing has led to headaches (e.g. automatically setting a MAC address
in the parser when one isn't specified in the input XML).
This patch reverts commit b0e2bb33 and replaces it with the alternate
implementation of simply inserting the default value in the
appropriate place on the qemu commandline when no value is provided.
---
(Playing the devil's advocate on my own patch for a moment - one
advantage of Christophe's method of setting the default is that if we
use that object somewhere else in libvirt's code in the future, the
value will be set even if the XML left it unset, but with my method we
will have to check for a NULL name and replace it with the default
value anywhere we want to use it. So I won't say that either method is
definitely the proper way to go, but will just present this
alternative and see if someone else has an even stronger opinion than
me :-)
(BTW, I think I've decided while typing this message that, if we
decide to change from the original method of setting default to this
new method, the change should be pushed as two separate patches - one
reverting the original, and another adding the new. It's too close to
morning for me to take the time to do that right now, though.)
src/conf/domain_conf.c | 7 -------
src/qemu/qemu_command.c | 6 +++---
2 files changed, 3 insertions(+), 10 deletions(-)
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 24e10e6..ea558bb 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -5248,13 +5248,6 @@ virDomainChrDefParseXML(virCapsPtr caps,
goto error;
} else {
def->source.data.spicevmc = VIR_DOMAIN_CHR_SPICEVMC_VDAGENT;
- if (!def->target.name) {
- def->target.name = strdup("com.redhat.spice.0");
- if (!def->target.name) {
- virReportOOMError();
- goto error;
- }
- }
}
}
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 3d2bb6b..50b1e6d 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3457,9 +3457,9 @@ qemuBuildVirtioSerialPortDevStr(virDomainChrDefPtr dev,
qemuCapsGet(qemuCaps, QEMU_CAPS_DEVICE_SPICEVMC))) {
virBufferAsprintf(&buf, ",chardev=char%s,id=%s",
dev->info.alias, dev->info.alias);
- if (dev->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL &&
- dev->target.name) {
- virBufferAsprintf(&buf, ",name=%s", dev->target.name);
+ if (dev->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL) {
+ virBufferAsprintf(&buf, ",name=%s", dev->target.name
+ ? dev->target.name : "com.redhat.spice.0");
}
} else {
virBufferAsprintf(&buf, ",id=%s", dev->info.alias);
--
1.7.7.6
3:43 a.m.
New subject: [libvirt] [PATCH] qemu: set default name for SPICE agent channel when generating command
Hey,
Patch looks good to me, thanks for writing it :)
Christophe
On Fri, Mar 30, 2012 at 03:50:37AM -0400, Laine Stump wrote:
commit b0e2bb33 set a default value for the SPICE agent channel by
inserting it during parsing of the channel XML. That method of setting
a default is problematic because it makes a format/parse roundtrip
unclean, and experience with setting other values as a side effect of
parsing has led to headaches (e.g. automatically setting a MAC address
in the parser when one isn't specified in the input XML).
This patch reverts commit b0e2bb33 and replaces it with the alternate
implementation of simply inserting the default value in the
appropriate place on the qemu commandline when no value is provided.
---
(Playing the devil's advocate on my own patch for a moment - one
advantage of Christophe's method of setting the default is that if we
use that object somewhere else in libvirt's code in the future, the
value will be set even if the XML left it unset, but with my method we
will have to check for a NULL name and replace it with the default
value anywhere we want to use it. So I won't say that either method is
definitely the proper way to go, but will just present this
alternative and see if someone else has an even stronger opinion than
me :-)
(BTW, I think I've decided while typing this message that, if we
decide to change from the original method of setting default to this
new method, the change should be pushed as two separate patches - one
reverting the original, and another adding the new. It's too close to
morning for me to take the time to do that right now, though.)
src/conf/domain_conf.c | 7 -------
src/qemu/qemu_command.c | 6 +++---
2 files changed, 3 insertions(+), 10 deletions(-)
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 24e10e6..ea558bb 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -5248,13 +5248,6 @@ virDomainChrDefParseXML(virCapsPtr caps,
goto error;
} else {
def->source.data.spicevmc = VIR_DOMAIN_CHR_SPICEVMC_VDAGENT;
- if (!def->target.name) {
- def->target.name = strdup("com.redhat.spice.0");
- if (!def->target.name) {
- virReportOOMError();
- goto error;
- }
- }
}
}
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 3d2bb6b..50b1e6d 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3457,9 +3457,9 @@ qemuBuildVirtioSerialPortDevStr(virDomainChrDefPtr dev,
qemuCapsGet(qemuCaps, QEMU_CAPS_DEVICE_SPICEVMC))) {
virBufferAsprintf(&buf, ",chardev=char%s,id=%s",
dev->info.alias, dev->info.alias);
- if (dev->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL &&
- dev->target.name) {
- virBufferAsprintf(&buf, ",name=%s", dev->target.name);
+ if (dev->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL) {
+ virBufferAsprintf(&buf, ",name=%s", dev->target.name
+ ? dev->target.name : "com.redhat.spice.0");
}
} else {
virBufferAsprintf(&buf, ",id=%s", dev->info.alias);
--
1.7.7.6
--
libvir-list mailing list
libvir-list(a)redhat.com
https://www.redhat.com/mailman/listinfo/libvir-list
10:06 a.m.
New subject: [libvirt] [PATCH] qemu: set default name for SPICE agent channel when generating command
On 30.03.2012 09:50, Laine Stump wrote:
commit b0e2bb33 set a default value for the SPICE agent channel by
inserting it during parsing of the channel XML. That method of setting
a default is problematic because it makes a format/parse roundtrip
unclean, and experience with setting other values as a side effect of
parsing has led to headaches (e.g. automatically setting a MAC address
in the parser when one isn't specified in the input XML).
This patch reverts commit b0e2bb33 and replaces it with the alternate
implementation of simply inserting the default value in the
appropriate place on the qemu commandline when no value is provided.
---
(Playing the devil's advocate on my own patch for a moment - one
advantage of Christophe's method of setting the default is that if we
use that object somewhere else in libvirt's code in the future, the
value will be set even if the XML left it unset, but with my method we
will have to check for a NULL name and replace it with the default
value anywhere we want to use it. So I won't say that either method is
definitely the proper way to go, but will just present this
alternative and see if someone else has an even stronger opinion than
me :-)
(BTW, I think I've decided while typing this message that, if we
decide to change from the original method of setting default to this
new method, the change should be pushed as two separate patches - one
reverting the original, and another adding the new. It's too close to
morning for me to take the time to do that right now, though.)
src/conf/domain_conf.c | 7 -------
src/qemu/qemu_command.c | 6 +++---
2 files changed, 3 insertions(+), 10 deletions(-)
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 24e10e6..ea558bb 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -5248,13 +5248,6 @@ virDomainChrDefParseXML(virCapsPtr caps,
goto error;
} else {
def->source.data.spicevmc = VIR_DOMAIN_CHR_SPICEVMC_VDAGENT;
- if (!def->target.name) {
- def->target.name = strdup("com.redhat.spice.0");
- if (!def->target.name) {
- virReportOOMError();
- goto error;
- }
- }
}
}
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 3d2bb6b..50b1e6d 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3457,9 +3457,9 @@ qemuBuildVirtioSerialPortDevStr(virDomainChrDefPtr dev,
qemuCapsGet(qemuCaps, QEMU_CAPS_DEVICE_SPICEVMC))) {
virBufferAsprintf(&buf, ",chardev=char%s,id=%s",
dev->info.alias, dev->info.alias);
- if (dev->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL &&
- dev->target.name) {
- virBufferAsprintf(&buf, ",name=%s", dev->target.name);
+ if (dev->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL) {
+ virBufferAsprintf(&buf, ",name=%s", dev->target.name
+ ? dev->target.name : "com.redhat.spice.0");
}
} else {
virBufferAsprintf(&buf, ",id=%s", dev->info.alias);
ACK
Maybe it's worth squashing this in:
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 3d2bb6b..3a14727 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3444,8 +3444,7 @@ qemuBuildVirtioSerialPortDevStr(virDomainChrDefPtr
dev,
if (dev->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL &&
dev->source.type == VIR_DOMAIN_CHR_TYPE_SPICEVMC &&
- dev->target.name &&
- STRNEQ(dev->target.name, "com.redhat.spice.0")) {
+ STRNEQ_NULLABLE(dev->target.name, "com.redhat.spice.0")) {
qemuReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("Unsupported spicevmc target name '%s'"),
dev->target.name);
12:52 p.m.
New subject: [libvirt] [PATCH] qemu: set default name for SPICE agent channel when generating command
On 03/30/2012 11:06 AM, Michal Privoznik wrote:
On 30.03.2012 09:50, Laine Stump wrote:
> commit b0e2bb33 set a default value for the SPICE agent channel by
> inserting it during parsing of the channel XML. That method of setting
> a default is problematic because it makes a format/parse roundtrip
> unclean, and experience with setting other values as a side effect of
> parsing has led to headaches (e.g. automatically setting a MAC address
> in the parser when one isn't specified in the input XML).
>
> This patch reverts commit b0e2bb33 and replaces it with the alternate
> implementation of simply inserting the default value in the
> appropriate place on the qemu commandline when no value is provided.
> ---
>
> (Playing the devil's advocate on my own patch for a moment - one
> advantage of Christophe's method of setting the default is that if we
> use that object somewhere else in libvirt's code in the future, the
> value will be set even if the XML left it unset, but with my method we
> will have to check for a NULL name and replace it with the default
> value anywhere we want to use it. So I won't say that either method is
> definitely the proper way to go, but will just present this
> alternative and see if someone else has an even stronger opinion than
> me :-)
>
> (BTW, I think I've decided while typing this message that, if we
> decide to change from the original method of setting default to this
> new method, the change should be pushed as two separate patches - one
> reverting the original, and another adding the new. It's too close to
> morning for me to take the time to do that right now, though.)
>
> src/conf/domain_conf.c | 7 -------
> src/qemu/qemu_command.c | 6 +++---
> 2 files changed, 3 insertions(+), 10 deletions(-)
>
> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
> index 24e10e6..ea558bb 100644
> --- a/src/conf/domain_conf.c
> +++ b/src/conf/domain_conf.c
> @@ -5248,13 +5248,6 @@ virDomainChrDefParseXML(virCapsPtr caps,
> goto error;
> } else {
> def->source.data.spicevmc = VIR_DOMAIN_CHR_SPICEVMC_VDAGENT;
> - if (!def->target.name) {
> - def->target.name = strdup("com.redhat.spice.0");
> - if (!def->target.name) {
> - virReportOOMError();
> - goto error;
> - }
> - }
> }
> }
>
> diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
> index 3d2bb6b..50b1e6d 100644
> --- a/src/qemu/qemu_command.c
> +++ b/src/qemu/qemu_command.c
> @@ -3457,9 +3457,9 @@ qemuBuildVirtioSerialPortDevStr(virDomainChrDefPtr dev,
> qemuCapsGet(qemuCaps, QEMU_CAPS_DEVICE_SPICEVMC))) {
> virBufferAsprintf(&buf, ",chardev=char%s,id=%s",
> dev->info.alias, dev->info.alias);
> - if (dev->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL &&
> - dev->target.name) {
> - virBufferAsprintf(&buf, ",name=%s", dev->target.name);
> + if (dev->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL) {
> + virBufferAsprintf(&buf, ",name=%s", dev->target.name
> + ? dev->target.name :
"com.redhat.spice.0");
> }
> } else {
> virBufferAsprintf(&buf, ",id=%s", dev->info.alias);
ACK
Maybe it's worth squashing this in:
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 3d2bb6b..3a14727 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3444,8 +3444,7 @@ qemuBuildVirtioSerialPortDevStr(virDomainChrDefPtr
dev,
if (dev->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL &&
dev->source.type == VIR_DOMAIN_CHR_TYPE_SPICEVMC &&
- dev->target.name &&
- STRNEQ(dev->target.name, "com.redhat.spice.0")) {
+ STRNEQ_NULLABLE(dev->target.name, "com.redhat.spice.0")) {
Sure, that's a nice reduction in line count, and optimization.
I pushed it with that change.
Thanks! (to Eric and Christophe as well).
4619
days inactive
4626
days old
10 comments
4 participants
participants (4)
-
Christophe Fergeau -
Eric Blake -
Laine Stump -
Michal Privoznik