[libvirt] libxl: Enable video device selection for Xen
Sorry, this fell complete off my todos for a while. So I split off the fixup of VRAM into a separate patch which may or may not be used and only accept vga, xen and cirrus as supported types in the main patch. I believe I saw some discussions about how to fix some of the VRAM values as they are passed into qemu. At least for the Cirrus type I saw that the command line looked ok but the guest was getting a much larger VRAM size than it was told. -Stefan
This started as an investigation into an issue where libvirt (using the libxl driver) and the Xen host, like an old couple, could not agree on who is responsible for selecting the VNC port to use. Things usually (and a bit surprisingly) did work because, just like that old couple, they had the same idea on what to do by default. However it was possible that this ended up in a big argument. The problem is that display information exists in two different places: in the vfbs list and in the build info. And for launching the device model, only the latter is used. But that never gets initialized from libvirt. So Xen allows the device model to select a default port while libvirt thinks it has told Xen that this is done by libvirt (though the vfbs config). While fixing that, I made a stab at actually evaluating the configuration of the video device. So that it is now possible to at least decide between a Cirrus or standard VGA emulation and to modify the VRAM within certain limits using libvirt. [v2: Check return code of VIR_STRDUP and fix indentation] [v3: Split out VRAM fixup and return error for unsupported video type] Signed-off-by: Stefan Bader <stefan.bader@canonical.com> --- src/libxl/libxl_conf.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c index b7fed7f..2b5c469 100644 --- a/src/libxl/libxl_conf.c +++ b/src/libxl/libxl_conf.c @@ -1304,6 +1304,64 @@ libxlMakeCapabilities(libxl_ctx *ctx) return NULL; } +static int +libxlSetBuildGraphics(virDomainDefPtr def, libxl_domain_config *d_config) +{ + libxl_domain_build_info *b_info = &d_config->b_info; + + /* + * Take the first defined video device (graphics card) to display + * on the first graphics device (display). + * Right now only type and vram info is used and anything beside + * type xen and vga is mapped to cirrus. + */ + if (def->nvideos) { + switch (def->videos[0]->type) { + case VIR_DOMAIN_VIDEO_TYPE_VGA: + case VIR_DOMAIN_VIDEO_TYPE_XEN: + b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_STD; + break; + case VIR_DOMAIN_VIDEO_TYPE_CIRRUS: + b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_CIRRUS; + break; + default: + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + "%s", + _("video type not supported by libxl")); + return -1; + } + b_info->video_memkb = def->videos[0]->vram ? + def->videos[0]->vram : + LIBXL_MEMKB_DEFAULT; + } else { + libxl_defbool_set(&b_info->u.hvm.nographic, 1); + } + + /* + * When making the list of displays, only VNC and SDL types were + * taken into account. So it seems sensible to connect the default + * video device to the first in the vfb list. + */ + if (d_config->num_vfbs) { + libxl_device_vfb *vfb0 = &d_config->vfbs[0]; + + b_info->u.hvm.vnc = vfb0->vnc; + if (VIR_STRDUP(b_info->u.hvm.vnc.listen, vfb0->vnc.listen) < 0) + return -1; + if (VIR_STRDUP(b_info->u.hvm.vnc.passwd, vfb0->vnc.passwd) < 0) + return -1; + b_info->u.hvm.sdl = vfb0->sdl; + if (VIR_STRDUP(b_info->u.hvm.sdl.display, vfb0->sdl.display) < 0) + return -1; + if (VIR_STRDUP(b_info->u.hvm.sdl.xauthority, vfb0->sdl.xauthority) < 0) + return -1; + if (VIR_STRDUP(b_info->u.hvm.keymap, vfb0->keymap) < 0) + return -1; + } + + return 0; +} + int libxlBuildDomainConfig(libxlDriverPrivatePtr driver, virDomainObjPtr vm, libxl_domain_config *d_config) @@ -1331,6 +1389,16 @@ libxlBuildDomainConfig(libxlDriverPrivatePtr driver, if (libxlMakePCIList(def, d_config) < 0) return -1; + /* + * Now that any potential VFBs are defined, it is time to update the + * build info with the data of the primary display. Some day libxl + * might implicitely do so but as it does not right now, better be + * explicit. + */ + if (d_config->c_info.type == LIBXL_DOMAIN_TYPE_HVM) + if (libxlSetBuildGraphics(def, d_config) < 0) + return -1; + d_config->on_reboot = def->onReboot; d_config->on_poweroff = def->onPoweroff; d_config->on_crash = def->onCrash; -- 1.7.9.5
Hi Stefan, Thanks for the patches, sorry for the delay... Stefan Bader wrote:
This started as an investigation into an issue where libvirt (using the libxl driver) and the Xen host, like an old couple, could not agree on who is responsible for selecting the VNC port to use.
Things usually (and a bit surprisingly) did work because, just like that old couple, they had the same idea on what to do by default. However it was possible that this ended up in a big argument.
The problem is that display information exists in two different places: in the vfbs list and in the build info. And for launching the device model, only the latter is used. But that never gets initialized from libvirt. So Xen allows the device model to select a default port while libvirt thinks it has told Xen that this is done by libvirt (though the vfbs config).
While fixing that, I made a stab at actually evaluating the configuration of the video device. So that it is now possible to at least decide between a Cirrus or standard VGA emulation and to modify the VRAM within certain limits using libvirt.
[v2: Check return code of VIR_STRDUP and fix indentation] [v3: Split out VRAM fixup and return error for unsupported video type]
Signed-off-by: Stefan Bader <stefan.bader@canonical.com> --- src/libxl/libxl_conf.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+)
diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c index b7fed7f..2b5c469 100644 --- a/src/libxl/libxl_conf.c +++ b/src/libxl/libxl_conf.c @@ -1304,6 +1304,64 @@ libxlMakeCapabilities(libxl_ctx *ctx) return NULL; }
+static int +libxlSetBuildGraphics(virDomainDefPtr def, libxl_domain_config *d_config) +{ + libxl_domain_build_info *b_info = &d_config->b_info; + + /* + * Take the first defined video device (graphics card) to display + * on the first graphics device (display). + * Right now only type and vram info is used and anything beside + * type xen and vga is mapped to cirrus. + */ + if (def->nvideos) { + switch (def->videos[0]->type) { + case VIR_DOMAIN_VIDEO_TYPE_VGA: + case VIR_DOMAIN_VIDEO_TYPE_XEN: + b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_STD; + break; + case VIR_DOMAIN_VIDEO_TYPE_CIRRUS: + b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_CIRRUS; + break; + default: + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + "%s", + _("video type not supported by libxl")); + return -1; + } + b_info->video_memkb = def->videos[0]->vram ? + def->videos[0]->vram : + LIBXL_MEMKB_DEFAULT; + } else { + libxl_defbool_set(&b_info->u.hvm.nographic, 1); + }
This part configures a video device.
+ + /* + * When making the list of displays, only VNC and SDL types were + * taken into account. So it seems sensible to connect the default + * video device to the first in the vfb list. + */ + if (d_config->num_vfbs) { + libxl_device_vfb *vfb0 = &d_config->vfbs[0]; + + b_info->u.hvm.vnc = vfb0->vnc; + if (VIR_STRDUP(b_info->u.hvm.vnc.listen, vfb0->vnc.listen) < 0) + return -1; + if (VIR_STRDUP(b_info->u.hvm.vnc.passwd, vfb0->vnc.passwd) < 0) + return -1; + b_info->u.hvm.sdl = vfb0->sdl; + if (VIR_STRDUP(b_info->u.hvm.sdl.display, vfb0->sdl.display) < 0) + return -1; + if (VIR_STRDUP(b_info->u.hvm.sdl.xauthority, vfb0->sdl.xauthority) < 0) + return -1; + if (VIR_STRDUP(b_info->u.hvm.keymap, vfb0->keymap) < 0) + return -1; + } + + return 0; +}
And this part configures a frame buffer. I think it would be better for this part to be in libxlMakeVfbList(), similar to commit b55cc5f4. This function then becomes libxlMakeVideo(), continuing the libxlMake<Device> pattern. Regards, Jim
+ int libxlBuildDomainConfig(libxlDriverPrivatePtr driver, virDomainObjPtr vm, libxl_domain_config *d_config) @@ -1331,6 +1389,16 @@ libxlBuildDomainConfig(libxlDriverPrivatePtr driver, if (libxlMakePCIList(def, d_config) < 0) return -1;
+ /* + * Now that any potential VFBs are defined, it is time to update the + * build info with the data of the primary display. Some day libxl + * might implicitely do so but as it does not right now, better be + * explicit. + */ + if (d_config->c_info.type == LIBXL_DOMAIN_TYPE_HVM) + if (libxlSetBuildGraphics(def, d_config) < 0) + return -1; + d_config->on_reboot = def->onReboot; d_config->on_poweroff = def->onPoweroff; d_config->on_crash = def->onCrash;
being as bad with timely responses. Ok, so how about the following? One note: it could be the STRDUP's are not strictly needed. But to me it felt wrong to have two places refer to the same strings (as MakeVFB copies the struct containing the pointers). If this is not needed, then all changes now in MakeVFB probably can be dropped (except setting the keyboard layout, maybe; which I might miss ;)). -Stefan
From a95db265fa4c1a231e7c2d70baa360c6a0500e3b Mon Sep 17 00:00:00 2001 From: Stefan Bader <stefan.bader@canonical.com> Date: Thu, 27 Mar 2014 16:01:18 +0100 Subject: [PATCH] libxl: Implement basic video device selection
This started as an investigation into an issue where libvirt (using the libxl driver) and the Xen host, like an old couple, could not agree on who is responsible for selecting the VNC port to use. Things usually (and a bit surprisingly) did work because, just like that old couple, they had the same idea on what to do by default. However it was possible that this ended up in a big argument. The problem is that display information exists in two different places: in the vfbs list and in the build info. And for launching the device model, only the latter is used. But that never gets initialized from libvirt. So Xen allows the device model to select a default port while libvirt thinks it has told Xen that this is done by libvirt (though the vfbs config). While fixing that, I made a stab at actually evaluating the configuration of the video device. So that it is now possible to at least decide between a Cirrus or standard VGA emulation and to modify the VRAM within certain limits using libvirt. [v2: Check return code of VIR_STRDUP and fix indentation] [v3: Split out VRAM fixup and return error for unsupported video type] [v4: Re-arrange code and move VFB setup into libxlMakeVfbList] Signed-off-by: Stefan Bader <stefan.bader@canonical.com> --- src/libxl/libxl_conf.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 61 insertions(+), 2 deletions(-) diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c index 8eeaf82..43cabcf 100644 --- a/src/libxl/libxl_conf.c +++ b/src/libxl/libxl_conf.c @@ -1098,10 +1098,21 @@ libxlMakeVfbList(virPortAllocatorPtr graphicsports, libxl_domain_build_info *b_info = &d_config->b_info; libxl_device_vfb vfb = d_config->vfbs[0]; - if (libxl_defbool_val(vfb.vnc.enable)) + if (libxl_defbool_val(vfb.vnc.enable)) { memcpy(&b_info->u.hvm.vnc, &vfb.vnc, sizeof(libxl_vnc_info)); - else if (libxl_defbool_val(vfb.sdl.enable)) + if (VIR_STRDUP(b_info->u.hvm.vnc.listen, vfb.vnc.listen) < 0) + goto error; + if (VIR_STRDUP(b_info->u.hvm.vnc.passwd, vfb.vnc.passwd) < 0) + goto error; + } else if (libxl_defbool_val(vfb.sdl.enable)) { memcpy(&b_info->u.hvm.sdl, &vfb.sdl, sizeof(libxl_sdl_info)); + if (VIR_STRDUP(b_info->u.hvm.sdl.display, vfb.sdl.display) < 0) + goto error; + if (VIR_STRDUP(b_info->u.hvm.sdl.xauthority, vfb.sdl.xauthority) < 0) + goto error; + } + if (VIR_STRDUP(b_info->u.hvm.keymap, vfb.keymap) < 0) + goto error; } return 0; @@ -1363,6 +1374,45 @@ libxlMakeCapabilities(libxl_ctx *ctx) return NULL; } +static int +libxlMakeVideo(virDomainDefPtr def, libxl_domain_config *d_config) +{ + libxl_domain_build_info *b_info = &d_config->b_info; + + if (d_config->c_info.type != LIBXL_DOMAIN_TYPE_HVM) + return 0; + + /* + * Take the first defined video device (graphics card) to display + * on the first graphics device (display). + * Right now only type and vram info is used and anything beside + * type xen and vga is mapped to cirrus. + */ + if (def->nvideos) { + switch (def->videos[0]->type) { + case VIR_DOMAIN_VIDEO_TYPE_VGA: + case VIR_DOMAIN_VIDEO_TYPE_XEN: + b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_STD; + break; + case VIR_DOMAIN_VIDEO_TYPE_CIRRUS: + b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_CIRRUS; + break; + default: + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + "%s", + _("video type not supported by libxl")); + return -1; + } + b_info->video_memkb = def->videos[0]->vram ? + def->videos[0]->vram : + LIBXL_MEMKB_DEFAULT; + } else { + libxl_defbool_set(&b_info->u.hvm.nographic, 1); + } + + return 0; +} + int libxlBuildDomainConfig(virPortAllocatorPtr graphicsports, virDomainDefPtr def, @@ -1389,6 +1439,15 @@ libxlBuildDomainConfig(virPortAllocatorPtr graphicsports, if (libxlMakePCIList(def, d_config) < 0) return -1; + /* + * Now that any potential VFBs are defined, it is time to update the + * build info with the data of the primary display. Some day libxl + * might implicitely do so but as it does not right now, better be + * explicit. + */ + if (libxlMakeVideo(def, d_config) < 0) + return -1; + d_config->on_reboot = def->onReboot; d_config->on_poweroff = def->onPoweroff; d_config->on_crash = def->onCrash; -- 1.7.9.5
Stefan Bader wrote:
being as bad with timely responses. Ok, so how about the following?
One note: it could be the STRDUP's are not strictly needed. But to me it felt wrong to have two places refer to the same strings (as MakeVFB copies the struct containing the pointers).
Agreed. Without the STRDUP's, seems there is a potential for double free when libxl_device_vfb and libxl_domain_config objects are disposed.
If this is not needed, then all changes now in MakeVFB probably can be dropped (except setting the keyboard layout, maybe; which I might miss ;)).
-Stefan
From a95db265fa4c1a231e7c2d70baa360c6a0500e3b Mon Sep 17 00:00:00 2001 From: Stefan Bader <stefan.bader@canonical.com> Date: Thu, 27 Mar 2014 16:01:18 +0100 Subject: [PATCH] libxl: Implement basic video device selection
This started as an investigation into an issue where libvirt (using the libxl driver) and the Xen host, like an old couple, could not agree on who is responsible for selecting the VNC port to use.
Things usually (and a bit surprisingly) did work because, just like that old couple, they had the same idea on what to do by default. However it was possible that this ended up in a big argument.
The problem is that display information exists in two different places: in the vfbs list and in the build info. And for launching the device model, only the latter is used. But that never gets initialized from libvirt. So Xen allows the device model to select a default port while libvirt thinks it has told Xen that this is done by libvirt (though the vfbs config).
While fixing that, I made a stab at actually evaluating the configuration of the video device. So that it is now possible to at least decide between a Cirrus or standard VGA emulation and to modify the VRAM within certain limits using libvirt.
[v2: Check return code of VIR_STRDUP and fix indentation] [v3: Split out VRAM fixup and return error for unsupported video type] [v4: Re-arrange code and move VFB setup into libxlMakeVfbList]
[meta-comment] libvirt prefers patch version history like this to be below the '---' following your Signed-off-by, so as to not pollute the commit message.
Signed-off-by: Stefan Bader <stefan.bader@canonical.com> --- src/libxl/libxl_conf.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 61 insertions(+), 2 deletions(-)
diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c index 8eeaf82..43cabcf 100644 --- a/src/libxl/libxl_conf.c +++ b/src/libxl/libxl_conf.c @@ -1098,10 +1098,21 @@ libxlMakeVfbList(virPortAllocatorPtr graphicsports, libxl_domain_build_info *b_info = &d_config->b_info; libxl_device_vfb vfb = d_config->vfbs[0];
- if (libxl_defbool_val(vfb.vnc.enable)) + if (libxl_defbool_val(vfb.vnc.enable)) { memcpy(&b_info->u.hvm.vnc, &vfb.vnc, sizeof(libxl_vnc_info)); - else if (libxl_defbool_val(vfb.sdl.enable)) + if (VIR_STRDUP(b_info->u.hvm.vnc.listen, vfb.vnc.listen) < 0) + goto error; + if (VIR_STRDUP(b_info->u.hvm.vnc.passwd, vfb.vnc.passwd) < 0) + goto error; + } else if (libxl_defbool_val(vfb.sdl.enable)) { memcpy(&b_info->u.hvm.sdl, &vfb.sdl, sizeof(libxl_sdl_info)); + if (VIR_STRDUP(b_info->u.hvm.sdl.display, vfb.sdl.display) < 0) + goto error; + if (VIR_STRDUP(b_info->u.hvm.sdl.xauthority, vfb.sdl.xauthority) < 0) + goto error; + } + if (VIR_STRDUP(b_info->u.hvm.keymap, vfb.keymap) < 0) + goto error; }
return 0; @@ -1363,6 +1374,45 @@ libxlMakeCapabilities(libxl_ctx *ctx) return NULL; }
+static int +libxlMakeVideo(virDomainDefPtr def, libxl_domain_config *d_config) +{ + libxl_domain_build_info *b_info = &d_config->b_info; + + if (d_config->c_info.type != LIBXL_DOMAIN_TYPE_HVM) + return 0; + + /* + * Take the first defined video device (graphics card) to display + * on the first graphics device (display). + * Right now only type and vram info is used and anything beside + * type xen and vga is mapped to cirrus. + */ + if (def->nvideos) { + switch (def->videos[0]->type) { + case VIR_DOMAIN_VIDEO_TYPE_VGA: + case VIR_DOMAIN_VIDEO_TYPE_XEN: + b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_STD; + break; + case VIR_DOMAIN_VIDEO_TYPE_CIRRUS: + b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_CIRRUS; + break; + default: + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + "%s", + _("video type not supported by libxl")); + return -1; + } + b_info->video_memkb = def->videos[0]->vram ? + def->videos[0]->vram : + LIBXL_MEMKB_DEFAULT;
While testing this, I noticed that libvirt will set vram to 9216 if not specified. E.g. # cat test.xml ... <video> <model type='vga'/> </video> ... # virsh define test.xml # virsh dumpxml test ... <video> <model type='vga' vram='9216' heads='1'/> </video> ... With type='vga', libxl will then fail to start the domain libxl: error: libxl_create.c:253:libxl__domain_build_info_setdefault: videoram must be at least 16 MB for STDVGA on QEMU_XEN This could be handled in libxlDomainDeviceDefPostParse(), where we can check for sane vram values for the various VIR_DOMAIN_VIDEO_TYPE_*, or set sane defaults if vram is not specified. BTW, sorry again for the delayed response. I somehow missed your message and only stumbled across it today :-/. And be warned that any followup may be delayed as I'll be on vacation July 18-27. Regards, Jim
+ } else { + libxl_defbool_set(&b_info->u.hvm.nographic, 1); + } + + return 0; +} + int libxlBuildDomainConfig(virPortAllocatorPtr graphicsports, virDomainDefPtr def, @@ -1389,6 +1439,15 @@ libxlBuildDomainConfig(virPortAllocatorPtr graphicsports, if (libxlMakePCIList(def, d_config) < 0) return -1;
+ /* + * Now that any potential VFBs are defined, it is time to update the + * build info with the data of the primary display. Some day libxl + * might implicitely do so but as it does not right now, better be + * explicit. + */ + if (libxlMakeVideo(def, d_config) < 0) + return -1; + d_config->on_reboot = def->onReboot; d_config->on_poweroff = def->onPoweroff; d_config->on_crash = def->onCrash;
On 07/16/2014 03:05 PM, Jim Fehlig wrote:
+ b_info->video_memkb = def->videos[0]->vram ? + def->videos[0]->vram : + LIBXL_MEMKB_DEFAULT;
While testing this, I noticed that libvirt will set vram to 9216 if not specified. E.g.
The 9216 default for qemu is absolutely stupid. No real hardware has a limit of 9M (8M or 16M are more likely). Please feel free to not perpetuate that stupidity into libxl.
With type='vga', libxl will then fail to start the domain
libxl: error: libxl_create.c:253:libxl__domain_build_info_setdefault: videoram must be at least 16 MB for STDVGA on QEMU_XEN
This could be handled in libxlDomainDeviceDefPostParse(), where we can check for sane vram values for the various VIR_DOMAIN_VIDEO_TYPE_*, or set sane defaults if vram is not specified.
Sounds like for libxl, a sane default is 16M. -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org
On 16.07.2014 23:05, Jim Fehlig wrote:
Stefan Bader wrote:
being as bad with timely responses. Ok, so how about the following?
One note: it could be the STRDUP's are not strictly needed. But to me it felt wrong to have two places refer to the same strings (as MakeVFB copies the struct containing the pointers).
Agreed. Without the STRDUP's, seems there is a potential for double free when libxl_device_vfb and libxl_domain_config objects are disposed.
If this is not needed, then all changes now in MakeVFB probably can be dropped (except setting the keyboard layout, maybe; which I might miss ;)).
-Stefan
From a95db265fa4c1a231e7c2d70baa360c6a0500e3b Mon Sep 17 00:00:00 2001 From: Stefan Bader <stefan.bader@canonical.com> Date: Thu, 27 Mar 2014 16:01:18 +0100 Subject: [PATCH] libxl: Implement basic video device selection
This started as an investigation into an issue where libvirt (using the libxl driver) and the Xen host, like an old couple, could not agree on who is responsible for selecting the VNC port to use.
Things usually (and a bit surprisingly) did work because, just like that old couple, they had the same idea on what to do by default. However it was possible that this ended up in a big argument.
The problem is that display information exists in two different places: in the vfbs list and in the build info. And for launching the device model, only the latter is used. But that never gets initialized from libvirt. So Xen allows the device model to select a default port while libvirt thinks it has told Xen that this is done by libvirt (though the vfbs config).
While fixing that, I made a stab at actually evaluating the configuration of the video device. So that it is now possible to at least decide between a Cirrus or standard VGA emulation and to modify the VRAM within certain limits using libvirt.
[v2: Check return code of VIR_STRDUP and fix indentation] [v3: Split out VRAM fixup and return error for unsupported video type] [v4: Re-arrange code and move VFB setup into libxlMakeVfbList]
[meta-comment] libvirt prefers patch version history like this to be below the '---' following your Signed-off-by, so as to not pollute the commit message.
Ah yeah, makes sense. I try to keep it in mind.
Signed-off-by: Stefan Bader <stefan.bader@canonical.com> --- src/libxl/libxl_conf.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 61 insertions(+), 2 deletions(-)
diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c index 8eeaf82..43cabcf 100644 --- a/src/libxl/libxl_conf.c +++ b/src/libxl/libxl_conf.c @@ -1098,10 +1098,21 @@ libxlMakeVfbList(virPortAllocatorPtr graphicsports, libxl_domain_build_info *b_info = &d_config->b_info; libxl_device_vfb vfb = d_config->vfbs[0];
- if (libxl_defbool_val(vfb.vnc.enable)) + if (libxl_defbool_val(vfb.vnc.enable)) { memcpy(&b_info->u.hvm.vnc, &vfb.vnc, sizeof(libxl_vnc_info)); - else if (libxl_defbool_val(vfb.sdl.enable)) + if (VIR_STRDUP(b_info->u.hvm.vnc.listen, vfb.vnc.listen) < 0) + goto error; + if (VIR_STRDUP(b_info->u.hvm.vnc.passwd, vfb.vnc.passwd) < 0) + goto error; + } else if (libxl_defbool_val(vfb.sdl.enable)) { memcpy(&b_info->u.hvm.sdl, &vfb.sdl, sizeof(libxl_sdl_info)); + if (VIR_STRDUP(b_info->u.hvm.sdl.display, vfb.sdl.display) < 0) + goto error; + if (VIR_STRDUP(b_info->u.hvm.sdl.xauthority, vfb.sdl.xauthority) < 0) + goto error; + } + if (VIR_STRDUP(b_info->u.hvm.keymap, vfb.keymap) < 0) + goto error; }
return 0; @@ -1363,6 +1374,45 @@ libxlMakeCapabilities(libxl_ctx *ctx) return NULL; }
+static int +libxlMakeVideo(virDomainDefPtr def, libxl_domain_config *d_config) +{ + libxl_domain_build_info *b_info = &d_config->b_info; + + if (d_config->c_info.type != LIBXL_DOMAIN_TYPE_HVM) + return 0; + + /* + * Take the first defined video device (graphics card) to display + * on the first graphics device (display). + * Right now only type and vram info is used and anything beside + * type xen and vga is mapped to cirrus. + */ + if (def->nvideos) { + switch (def->videos[0]->type) { + case VIR_DOMAIN_VIDEO_TYPE_VGA: + case VIR_DOMAIN_VIDEO_TYPE_XEN: + b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_STD; + break; + case VIR_DOMAIN_VIDEO_TYPE_CIRRUS: + b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_CIRRUS; + break; + default: + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + "%s", + _("video type not supported by libxl")); + return -1; + } + b_info->video_memkb = def->videos[0]->vram ? + def->videos[0]->vram : + LIBXL_MEMKB_DEFAULT;
While testing this, I noticed that libvirt will set vram to 9216 if not specified. E.g.
# cat test.xml ... <video> <model type='vga'/> </video> ... # virsh define test.xml # virsh dumpxml test ... <video> <model type='vga' vram='9216' heads='1'/> </video> ...
With type='vga', libxl will then fail to start the domain
libxl: error: libxl_create.c:253:libxl__domain_build_info_setdefault: videoram must be at least 16 MB for STDVGA on QEMU_XEN
Heh, thats "funny". At least this was the same thing I observed when creating new guests with virt-manager. Maybe I blamed the wrong part of the stack. Or they both do it. This lead the the second part of my changes which was not so clear about whether it should or should not go upstream. So from my side a fixup of some kind would be good but we can work on this in a follow-up.
This could be handled in libxlDomainDeviceDefPostParse(), where we can check for sane vram values for the various VIR_DOMAIN_VIDEO_TYPE_*, or set sane defaults if vram is not specified.
BTW, sorry again for the delayed response. I somehow missed your message and only stumbled across it today :-/. And be warned that any followup may be delayed as I'll be on vacation July 18-27.
Oh I am equally bad at having it sit in my reader and then getting back at random times. :) -Stefan
Regards, Jim
+ } else { + libxl_defbool_set(&b_info->u.hvm.nographic, 1); + } + + return 0; +} + int libxlBuildDomainConfig(virPortAllocatorPtr graphicsports, virDomainDefPtr def, @@ -1389,6 +1439,15 @@ libxlBuildDomainConfig(virPortAllocatorPtr graphicsports, if (libxlMakePCIList(def, d_config) < 0) return -1;
+ /* + * Now that any potential VFBs are defined, it is time to update the + * build info with the data of the primary display. Some day libxl + * might implicitely do so but as it does not right now, better be + * explicit. + */ + if (libxlMakeVideo(def, d_config) < 0) + return -1; + d_config->on_reboot = def->onReboot; d_config->on_poweroff = def->onPoweroff; d_config->on_crash = def->onCrash;
Stefan Bader wrote:
On 16.07.2014 23:05, Jim Fehlig wrote:
While testing this, I noticed that libvirt will set vram to 9216 if not specified. E.g.
# cat test.xml ... <video> <model type='vga'/> </video> ... # virsh define test.xml # virsh dumpxml test ... <video> <model type='vga' vram='9216' heads='1'/> </video> ...
With type='vga', libxl will then fail to start the domain
libxl: error: libxl_create.c:253:libxl__domain_build_info_setdefault: videoram must be at least 16 MB for STDVGA on QEMU_XEN
Heh, thats "funny". At least this was the same thing I observed when creating new guests with virt-manager. Maybe I blamed the wrong part of the stack. Or they both do it. This lead the the second part of my changes which was not so clear about whether it should or should not go upstream.
So from my side a fixup of some kind would be good but we can work on this in a follow-up.
The problem is, some domains may not start after applying this patch. Consider a domain with the following video config <video> <model type='vga' vram='9216' heads='1'/> </video> This would work pre-patch since libxl_domain_build_info->video_memkb would be initialized to LIBXL_MEMKB_DEFAULT when calling libxl_domain_build_info_init(). But the domain will fail to start post-patch since video_memkb is set to an invalid value. I know the current behavior is not correct either, but would be nice to fix everything up in one series. I started on a second patch that would validate input or set sane defaults in libxlDomainDeviceDefPostParse(), but while testing realized that sane defaults depend on which qemu is used. E.g. the minimum video_memkb values have doubled with QEMU_XEN vs QEMU_XEN_TRADITIONAL - see $xen_root/tools/libxl/libxl_create.c, libxl__domain_build_info_setdefault(). [I'll mention again that it is unfortunate that QEMU_XEN vs QEMU_XEN_TRADITIONAL leaked through the public API.] I'm thinking of writing a utility function to detect the old vs new qemu, hoping there is something in the help output or similar to determine which one <emulator> is. Such a function would be useful for David Scott's old patch to support arbitrary user-provided <emulator> https://www.redhat.com/archives/libvir-list/2013-April/msg02119.html But alas, this will have to wait until I return from vacation. Regards, Jim
This is a bit debatable. On one side it hides configuration errors in a way that makes them hard to spot. On the other side there is at least one issue with (maybe some older versions) virt-manager. Virt-manager sets VRAM directly, not using the default memory setting but uses too small values for libxl. Worse, those versions do not seem to allow to change VRAM from the GUI. So switching the video type to VGA makes the guest fail to start until one manually adapts the VRAM size in the XML definition. With this change this would not happen but VRAM will be bigger than the GUI says. This would not be that different from current Cirrus behaviour. Only that in that case qemu seems to ignore the provided size. Signed-off-by: Stefan Bader <stefan.bader@canonical.com> --- src/libxl/libxl_conf.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c index 2b5c469..9af8abe 100644 --- a/src/libxl/libxl_conf.c +++ b/src/libxl/libxl_conf.c @@ -1316,13 +1316,38 @@ libxlSetBuildGraphics(virDomainDefPtr def, libxl_domain_config *d_config) * type xen and vga is mapped to cirrus. */ if (def->nvideos) { + unsigned int min_vram = 8 * 1024; + switch (def->videos[0]->type) { case VIR_DOMAIN_VIDEO_TYPE_VGA: case VIR_DOMAIN_VIDEO_TYPE_XEN: b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_STD; + /* + * Libxl enforces a minimal VRAM size of 8M when using + * LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL or + * 16M for LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN. + * Avoid build failures and go with the minimum if less + * is specified. + */ + switch (b_info->device_model_version) { + case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL: + min_vram = 8 * 1024; + break; + case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN: + default: + min_vram = 16 * 1024; + } break; case VIR_DOMAIN_VIDEO_TYPE_CIRRUS: b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_CIRRUS; + switch (b_info->device_model_version) { + case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL: + min_vram = 4 * 1024; /* Actually the max, too */ + break; + case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN: + default: + min_vram = 8 * 1024; + } break; default: virReportError(VIR_ERR_CONFIG_UNSUPPORTED, @@ -1330,7 +1355,7 @@ libxlSetBuildGraphics(virDomainDefPtr def, libxl_domain_config *d_config) _("video type not supported by libxl")); return -1; } - b_info->video_memkb = def->videos[0]->vram ? + b_info->video_memkb = (def->videos[0]->vram >= min_vram) ? def->videos[0]->vram : LIBXL_MEMKB_DEFAULT; } else { -- 1.7.9.5
Stefan Bader wrote:
This is a bit debatable. On one side it hides configuration errors in a way that makes them hard to spot. On the other side there is at least one issue with (maybe some older versions) virt-manager. Virt-manager sets VRAM directly, not using the default memory setting but uses too small values for libxl.
It sounds like virt-manager should be fixed. I don't think the libxl driver should contain this type of policy. It could report errors on user-supplied configuration known not to work with libxl, but I don't think it should be silently changing the configuration. Regards, Jim
Worse, those versions do not seem to allow to change VRAM from the GUI. So switching the video type to VGA makes the guest fail to start until one manually adapts the VRAM size in the XML definition. With this change this would not happen but VRAM will be bigger than the GUI says. This would not be that different from current Cirrus behaviour. Only that in that case qemu seems to ignore the provided size.
Signed-off-by: Stefan Bader <stefan.bader@canonical.com> --- src/libxl/libxl_conf.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-)
diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c index 2b5c469..9af8abe 100644 --- a/src/libxl/libxl_conf.c +++ b/src/libxl/libxl_conf.c @@ -1316,13 +1316,38 @@ libxlSetBuildGraphics(virDomainDefPtr def, libxl_domain_config *d_config) * type xen and vga is mapped to cirrus. */ if (def->nvideos) { + unsigned int min_vram = 8 * 1024; + switch (def->videos[0]->type) { case VIR_DOMAIN_VIDEO_TYPE_VGA: case VIR_DOMAIN_VIDEO_TYPE_XEN: b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_STD; + /* + * Libxl enforces a minimal VRAM size of 8M when using + * LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL or + * 16M for LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN. + * Avoid build failures and go with the minimum if less + * is specified. + */ + switch (b_info->device_model_version) { + case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL: + min_vram = 8 * 1024; + break; + case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN: + default: + min_vram = 16 * 1024; + } break; case VIR_DOMAIN_VIDEO_TYPE_CIRRUS: b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_CIRRUS; + switch (b_info->device_model_version) { + case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL: + min_vram = 4 * 1024; /* Actually the max, too */ + break; + case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN: + default: + min_vram = 8 * 1024; + } break; default: virReportError(VIR_ERR_CONFIG_UNSUPPORTED, @@ -1330,7 +1355,7 @@ libxlSetBuildGraphics(virDomainDefPtr def, libxl_domain_config *d_config) _("video type not supported by libxl")); return -1; } - b_info->video_memkb = def->videos[0]->vram ? + b_info->video_memkb = (def->videos[0]->vram >= min_vram) ? def->videos[0]->vram : LIBXL_MEMKB_DEFAULT; } else {
participants (3)
-
Eric Blake -
Jim Fehlig -
Stefan Bader