On Mon, 10 Feb 2020 13:14:03 +0100
Christian Borntraeger <borntraeger@xxxxxxxxxx> wrote:
> On 10.02.20 12:54, Cornelia Huck wrote:
> > On Fri, 7 Feb 2020 06:39:26 -0500
> > Christian Borntraeger <borntraeger@xxxxxxxxxx> wrote:
> >
> >> From: Vasily Gorbik <gor@xxxxxxxxxxxxx>
> >>
> >> Add "prot_virt" command line option which controls if the kernel
> >> protected VMs support is enabled at early boot time. This has to be
> >> done early, because it needs large amounts of memory and will disable
> >> some features like STP time sync for the lpar.
> >>
> >> Extend ultravisor info definitions and expose it via uv_info struct
> >> filled in during startup.
> >>
> >> Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
> >> [borntraeger@xxxxxxxxxx: patch merging, splitting, fixing]
> >> Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
> >> ---
> >> .../admin-guide/kernel-parameters.txt | 5 ++
> >> arch/s390/boot/Makefile | 2 +-
> >> arch/s390/boot/uv.c | 21 +++++++-
> >> arch/s390/include/asm/uv.h | 46 +++++++++++++++--
> >> arch/s390/kernel/Makefile | 1 +
> >> arch/s390/kernel/setup.c | 4 --
> >> arch/s390/kernel/uv.c | 49 +++++++++++++++++++
> >> 7 files changed, 119 insertions(+), 9 deletions(-)
> >> create mode 100644 arch/s390/kernel/uv.c
> >
> > (...)
> >
> >> diff --git a/arch/s390/boot/Makefile b/arch/s390/boot/Makefile
> >> index e2c47d3a1c89..30f1811540c5 100644
> >> --- a/arch/s390/boot/Makefile
> >> +++ b/arch/s390/boot/Makefile
> >> @@ -37,7 +37,7 @@ CFLAGS_sclp_early_core.o += -I$(srctree)/drivers/s390/char
> >> obj-y := head.o als.o startup.o mem_detect.o ipl_parm.o ipl_report.o
> >> obj-y += string.o ebcdic.o sclp_early_core.o mem.o ipl_vmparm.o cmdline.o
> >> obj-y += version.o pgm_check_info.o ctype.o text_dma.o
> >> -obj-$(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) += uv.o
> >> +obj-$(findstring y, $(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) $(CONFIG_PGSTE)) += uv.o
> >
> > I'm wondering why you're checking CONFIG_PGSTE here...
>
> It was just simpler for a Makefile, because CONFIG_KVM can be m or y.
> PGSTE is always y when CONFIG_KVM is set. Suggestions welcome.
My only complaint is that it is a bit non-obvious at a glance... but
yeah, I don't have a better suggestion, either.
>
> [...]
>
> >> + prot_virt_host = 0;
> >> + pr_info("Running as protected virtualization guest.");
> >> + }
> >> +
> >> + if (prot_virt_host && !test_facility(158)) {
> >> + prot_virt_host = 0;
> >> + pr_info("The ultravisor call facility is not available.");
> >> + }
> >
> > What about prefixing these two with 'prot_virt:'? It seems the name is
> > settled now?
>
> It is not settled, but I can certainly do something like
>
> #define KMSG_COMPONENT "prot_virt"
> #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
>
>
> to prefix all pr_* calls in this file.
That would make it easier to associate any messages (especially the
second message here) with this feature, I think.
