2:15 p.m.
On Mon, 17 Apr 2017 14:22:20 -0600
Jim Fehlig <jfehlig(a)suse.com> wrote:
On 03/24/2017 03:02 PM, Wim Ten Have wrote:
> From: Wim ten Have <wim.ten.have(a)oracle.com>
>
> Per xen-xl conversions from and to native under host-passthrough
> mode we take care for Xen (nestedhvm = mode) applied and inherited
> settings generating or processing correct feature policy:
>
> [On Intel (VT-x) architectures]
> <feature policy='disable' name='vmx'/>
>
> or
>
> [On AMD (AMD-V) architectures]
> <feature policy='disable' name='svm'/>
>
> It will then generate (or parse) for nestedhvm=1 in/from xl format.
>
> Signed-off-by: Joao Martins <joao.m.martins(a)oracle.com>
> Signed-off-by: Wim ten Have <wim.ten.have(a)oracle.com>
> ---
> src/xenconfig/xen_xl.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 67 insertions(+)
>
> diff --git a/src/xenconfig/xen_xl.c b/src/xenconfig/xen_xl.c
> index 74f68b3..d3797b8 100644
> --- a/src/xenconfig/xen_xl.c
> +++ b/src/xenconfig/xen_xl.c
> @@ -106,6 +106,7 @@ xenParseXLOS(virConfPtr conf, virDomainDefPtr def, virCapsPtr
caps)
> if (def->os.type == VIR_DOMAIN_OSTYPE_HVM) {
> const char *bios;
> const char *boot;
> + int val = 0;
>
> if (xenConfigGetString(conf, "bios", &bios, NULL) < 0)
> return -1;
> @@ -164,6 +165,47 @@ xenParseXLOS(virConfPtr conf, virDomainDefPtr def, virCapsPtr
caps)
> }
> def->os.nBootDevs++;
> }
> +
> + if (xenConfigGetBool(conf, "nestedhvm", &val, -1) < 0)
> + return -1;
> +
> + if (val != -1) {
> + virCPUDefPtr cpu = NULL;
> +
> + if (VIR_ALLOC(cpu) < 0)
> + return -1;
> +
> + if (val == 0) {
> + if (VIR_ALLOC_N(cpu->features, 2) < 0)
> + goto cleanup;
> +
> + /*
> + * Below is pointless in real world but for purpose
> + * of testing let's check features depth holding at
> + * least multiple elements and also check if both
> + * vmx|svm are understood.
> + */
> + cpu->features[0].policy = VIR_CPU_FEATURE_DISABLE;
> + if (VIR_STRDUP(cpu->features[0].name, "vmx") < 0)
> + goto cleanup;
> + cpu->features[1].policy = VIR_CPU_FEATURE_DISABLE;
> + if (VIR_STRDUP(cpu->features[1].name, "svm") < 0)
> + goto cleanup;
Since caps is passed to this function, can it be used to determine whether to
disable vmx or svm?
Yes :-) ... thanks for enlightening me here as that is actually the correct
approach if non-test domain (conversion) actions are made under libvirtd.
There's one minor question here per me. To process caps for vmx|svm I'll
bring in virCPUCheckFeature() which at its turn requires me to include
"cpu/cpu.h"
for its prototype. Unfortunate cfg.mk does not anticipate and raises a
syntax-check caveat.
prohibit_cross_inclusion
src/xenconfig/xen_xl.c:51:#include "cpu/cpu.h"
maint.mk: unsafe cross-directory include
cfg.mk:773: recipe for target 'sc_prohibit_cross_inclusion' failed
make: *** [sc_prohibit_cross_inclusion] Error 1
That is ... unless I apply below change to cfg.mk.
- xenapi/ | xenconfig/ ) safe="($$dir|util|conf|xen)";; \
+ xenapi/ | xenconfig/ ) safe="($$dir|util|conf|xen|cpu)";; \
Is that lethal to do? I tried to reason and fail to see why not, ie. i
am a bit clueless for its specific reason ... but also new to whole arena.
> +
> + cpu->nfeatures = cpu->nfeatures_max = 2;
> + }
> + cpu->mode = VIR_CPU_MODE_HOST_PASSTHROUGH;
> + cpu->type = VIR_CPU_TYPE_GUEST;
> + def->cpu = cpu;
> + cpu = NULL;
> + cleanup:
> + if (cpu) {
> + VIR_FREE(cpu->features);
> + VIR_FREE(cpu);
> + return -1;
> + }
I'm not fond of the cleanup label in the middle of this function. If we can
disable only one of vmx or svm, then there will be one less strdup and one less
cleanup spot. Cleanup can then occur at the point of error.
Correct and given former change this will now nicely fold down under its
eventual failing VIR_STRDUP().
> + }
> +
> } else {
> if (xenConfigCopyStringOpt(conf, "bootloader",
&def->os.bootloader) < 0)
> return -1;
> @@ -897,6 +939,31 @@ xenFormatXLOS(virConfPtr conf, virDomainDefPtr def)
> if (xenConfigSetString(conf, "boot", boot) < 0)
> return -1;
>
> + if (def->cpu &&
> + def->cpu->mode == VIR_CPU_MODE_HOST_PASSTHROUGH) {
> + bool hasHwVirt = true;
> +
> + if (def->cpu->nfeatures) {
> + for (i = 0; i < def->cpu->nfeatures; i++) {
> +
> + switch (def->cpu->features[i].policy) {
> + case VIR_CPU_FEATURE_DISABLE:
> + case VIR_CPU_FEATURE_FORBID:
> + if (STREQ(def->cpu->features[i].name,
"vmx") ||
> + STREQ(def->cpu->features[i].name,
"svm"))
> + hasHwVirt = false;
> + break;
> +
> + default:
> + break;
Similar to patch 1, replace 'default' with the other enum values.
Sure!
Regards,
- Wim.
> + }
> + }
> + }
> +
> + if (xenConfigSetInt(conf, "nestedhvm", hasHwVirt) < 0)
> + return -1;
> + }
> +
> /* XXX floppy disks */
> } else {
> if (def->os.bootloader &&
>