| Message ID | 20200203131957.383915-3-borntraeger@de.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: s390: Add support for protected VMs | expand |
On Mon, 3 Feb 2020 08:19:22 -0500 Christian Borntraeger <borntraeger@de.ibm.com> wrote: > From: Vasily Gorbik <gor@linux.ibm.com> > > Introduce KVM_S390_PROTECTED_VIRTUALIZATION_HOST kbuild option for > protected virtual machines hosting support code. Hm... I seem to remember that you wanted to drop this config option and always build the code, in order to reduce complexity. Have you reconsidered this? > > 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@linux.ibm.com> > --- > .../admin-guide/kernel-parameters.txt | 5 ++ > arch/s390/boot/Makefile | 2 +- > arch/s390/boot/uv.c | 20 +++++++- > arch/s390/include/asm/uv.h | 46 ++++++++++++++++-- > arch/s390/kernel/Makefile | 1 + > arch/s390/kernel/setup.c | 4 -- > arch/s390/kernel/uv.c | 48 +++++++++++++++++++ > arch/s390/kvm/Kconfig | 19 ++++++++ > 8 files changed, 136 insertions(+), 9 deletions(-) > create mode 100644 arch/s390/kernel/uv.c (...) > diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c > new file mode 100644 > index 000000000000..35ce89695509 > --- /dev/null > +++ b/arch/s390/kernel/uv.c > @@ -0,0 +1,48 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Common Ultravisor functions and initialization > + * > + * Copyright IBM Corp. 2019 Happy new year? > + */ > +#include <linux/kernel.h> > +#include <linux/types.h> > +#include <linux/sizes.h> > +#include <linux/bitmap.h> > +#include <linux/memblock.h> > +#include <asm/facility.h> > +#include <asm/sections.h> > +#include <asm/uv.h> > + > +#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST > +int __bootdata_preserved(prot_virt_guest); Confused. You have this and uv_info below both in this file and in boot/uv.c. Is there some magic happening in __bootdata_preserved()? > +#endif > + > +#ifdef CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST > +int prot_virt_host; > +EXPORT_SYMBOL(prot_virt_host); > +struct uv_info __bootdata_preserved(uv_info); > +EXPORT_SYMBOL(uv_info); > + > +static int __init prot_virt_setup(char *val) > +{ > + bool enabled; > + int rc; > + > + rc = kstrtobool(val, &enabled); > + if (!rc && enabled) > + prot_virt_host = 1; > + > + if (is_prot_virt_guest() && prot_virt_host) { > + prot_virt_host = 0; > + pr_info("Running as protected virtualization guest."); Trying to disentangle that a bit in my mind... If we don't have facility 158, is_prot_virt_guest() will return 0. If protected host support has been requested, we'll print a message below (and turn it off). If the hardware provides the facilities for running as a protected virt guest, we turn off protected virt host support if requested and print a messages that we're a guest. Two questions: - Can the hardware ever provide both host and guest interfaces at the same time? I guess not; maybe add a comment? - Do we also want to print a message that we're running as a guest if the user didn't enable host support? If not, maybe prefix the message with "Cannot enable support for protected virtualization host:" or so? (Maybe also a good idea for the message below.) > + } > + > + if (prot_virt_host && !test_facility(158)) { > + prot_virt_host = 0; > + pr_info("The ultravisor call facility is not available."); > + } > + > + return rc; > +} > +early_param("prot_virt", prot_virt_setup); > +#endif (...)
On 03.02.20 18:12, Cornelia Huck wrote: > On Mon, 3 Feb 2020 08:19:22 -0500 > Christian Borntraeger <borntraeger@de.ibm.com> wrote: > >> From: Vasily Gorbik <gor@linux.ibm.com> >> >> Introduce KVM_S390_PROTECTED_VIRTUALIZATION_HOST kbuild option for >> protected virtual machines hosting support code. > > Hm... I seem to remember that you wanted to drop this config option and > always build the code, in order to reduce complexity. Have you > reconsidered this? I am still in favour of removing this, but I did not get an "yes, lets do it" answer. Since removing is easier than re-adding its still in. [...] >> + * Copyright IBM Corp. 2019 > > Happy new year? yep :-) [..] >> + >> +#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST >> +int __bootdata_preserved(prot_virt_guest); > > Confused. You have this and uv_info below both in this file and in > boot/uv.c. Is there some magic happening in __bootdata_preserved()? Yes, this is information that is transferred from the decompressor to Linux. I think we discussed about this the last time as well? > >> +#endif >> + >> +#ifdef CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST >> +int prot_virt_host; >> +EXPORT_SYMBOL(prot_virt_host); >> +struct uv_info __bootdata_preserved(uv_info); >> +EXPORT_SYMBOL(uv_info); >> + >> +static int __init prot_virt_setup(char *val) >> +{ >> + bool enabled; >> + int rc; >> + >> + rc = kstrtobool(val, &enabled); >> + if (!rc && enabled) >> + prot_virt_host = 1; >> + >> + if (is_prot_virt_guest() && prot_virt_host) { >> + prot_virt_host = 0; >> + pr_info("Running as protected virtualization guest."); > > Trying to disentangle that a bit in my mind... > > If we don't have facility 158, is_prot_virt_guest() will return 0. If > protected host support has been requested, we'll print a message below > (and turn it off). yes, a guest cannot be a host. > > If the hardware provides the facilities for running as a protected virt > guest, we turn off protected virt host support if requested and print a > messages that we're a guest. > > Two questions: > - Can the hardware ever provide both host and guest interfaces at the > same time? I guess not; maybe add a comment? Right, you are either guest or host. > - Do we also want to print a message that we're running as a guest if > the user didn't enable host support? If not, maybe prefix the message > with "Cannot enable support for protected virtualization host:" or > so? (Maybe also a good idea for the message below.) Line too long and I hate breaking string over multiple lines. I can change if somebody comes up with a proper message that is not too long.
On 03/02/2020 14.19, Christian Borntraeger wrote: > From: Vasily Gorbik <gor@linux.ibm.com> > > Introduce KVM_S390_PROTECTED_VIRTUALIZATION_HOST kbuild option for > protected virtual machines hosting support code. > > 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@linux.ibm.com> > --- [...] > diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h > index 4093a2856929..32eac3ab2d3b 100644 > --- a/arch/s390/include/asm/uv.h > +++ b/arch/s390/include/asm/uv.h > @@ -44,7 +44,19 @@ struct uv_cb_qui { > struct uv_cb_header header; > u64 reserved08; > u64 inst_calls_list[4]; > - u64 reserved30[15]; > + u64 reserved30[2]; > + u64 uv_base_stor_len; > + u64 reserved48; > + u64 conf_base_phys_stor_len; > + u64 conf_base_virt_stor_len; > + u64 conf_virt_var_stor_len; > + u64 cpu_stor_len; > + u32 reserved68[3]; If I count right, that should be named reserved70 instead? > + u32 max_num_sec_conf; > + u64 max_guest_stor_addr; > + u8 reserved80[150-128]; And this one reserved88[158 - 136] ? > + u16 max_guest_cpus; > + u64 reserved98; reservedA0 ? > } __packed __aligned(8); > Apart from that, the patch looks ok to me. Thomas
On 04.02.20 09:40, Thomas Huth wrote: > On 03/02/2020 14.19, Christian Borntraeger wrote: >> From: Vasily Gorbik <gor@linux.ibm.com> >> >> Introduce KVM_S390_PROTECTED_VIRTUALIZATION_HOST kbuild option for >> protected virtual machines hosting support code. >> >> 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@linux.ibm.com> >> --- > [...] >> diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h >> index 4093a2856929..32eac3ab2d3b 100644 >> --- a/arch/s390/include/asm/uv.h >> +++ b/arch/s390/include/asm/uv.h >> @@ -44,7 +44,19 @@ struct uv_cb_qui { >> struct uv_cb_header header; >> u64 reserved08; >> u64 inst_calls_list[4]; >> - u64 reserved30[15]; >> + u64 reserved30[2]; >> + u64 uv_base_stor_len; >> + u64 reserved48; >> + u64 conf_base_phys_stor_len; >> + u64 conf_base_virt_stor_len; >> + u64 conf_virt_var_stor_len; >> + u64 cpu_stor_len; >> + u32 reserved68[3]; > > If I count right, that should be named reserved70 instead? Right. Fixed. > >> + u32 max_num_sec_conf; >> + u64 max_guest_stor_addr; >> + u8 reserved80[150-128]; > > And this one reserved88[158 - 136] ? Right. Fixed > >> + u16 max_guest_cpus; >> + u64 reserved98; > > reservedA0 ? Fixed. (with lowercase a as in other s390 include files): > >> } __packed __aligned(8); >> > > Apart from that, the patch looks ok to me. Thanks
On Mon, 3 Feb 2020 23:03:42 +0100 Christian Borntraeger <borntraeger@de.ibm.com> wrote: > On 03.02.20 18:12, Cornelia Huck wrote: > > On Mon, 3 Feb 2020 08:19:22 -0500 > > Christian Borntraeger <borntraeger@de.ibm.com> wrote: > > > >> From: Vasily Gorbik <gor@linux.ibm.com> > >> > >> Introduce KVM_S390_PROTECTED_VIRTUALIZATION_HOST kbuild option for > >> protected virtual machines hosting support code. > > > > Hm... I seem to remember that you wanted to drop this config option and > > always build the code, in order to reduce complexity. Have you > > reconsidered this? > > I am still in favour of removing this, but I did not get an "yes, lets do > it" answer. Since removing is easier than re-adding its still in. ok > > [...] > >> + * Copyright IBM Corp. 2019 > > > > Happy new year? > > yep :-) > [..] > > >> + > >> +#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST > >> +int __bootdata_preserved(prot_virt_guest); > > > > Confused. You have this and uv_info below both in this file and in > > boot/uv.c. Is there some magic happening in __bootdata_preserved()? > > Yes, this is information that is transferred from the decompressor > to Linux. > I think we discussed about this the last time as well? I think I was confused about different things last time... But that is probably a sign that this wants a comment :) > > > > > >> +#endif > >> + > >> +#ifdef CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST > >> +int prot_virt_host; > >> +EXPORT_SYMBOL(prot_virt_host); > >> +struct uv_info __bootdata_preserved(uv_info); > >> +EXPORT_SYMBOL(uv_info); > >> + > >> +static int __init prot_virt_setup(char *val) > >> +{ > >> + bool enabled; > >> + int rc; > >> + > >> + rc = kstrtobool(val, &enabled); > >> + if (!rc && enabled) > >> + prot_virt_host = 1; > >> + > >> + if (is_prot_virt_guest() && prot_virt_host) { > >> + prot_virt_host = 0; > >> + pr_info("Running as protected virtualization guest."); > > > > Trying to disentangle that a bit in my mind... > > > > If we don't have facility 158, is_prot_virt_guest() will return 0. If > > protected host support has been requested, we'll print a message below > > (and turn it off). > > yes, a guest cannot be a host. > > > > If the hardware provides the facilities for running as a protected virt > > guest, we turn off protected virt host support if requested and print a > > messages that we're a guest. > > > > Two questions: > > - Can the hardware ever provide both host and guest interfaces at the > > same time? I guess not; maybe add a comment? > > Right, you are either guest or host. > > > - Do we also want to print a message that we're running as a guest if > > the user didn't enable host support? If not, maybe prefix the message > > with "Cannot enable support for protected virtualization host:" or > > so? (Maybe also a good idea for the message below.) > > Line too long and I hate breaking string over multiple lines. > I can change if somebody comes up with a proper message that is not too long. > Fair enough; it's just that it's not very clear from the messages in the log what happened. Maybe "prot_virt: Running as protected virtualization guest." "prot_virt: The ultravisor call facility is not available." That at least links back to the kernel parameter. [Aside: Would prot_virt_host be a better name? But that probably moves us into bikeshed territory.]
On 04.02.20 10:28, Cornelia Huck wrote: > On Mon, 3 Feb 2020 23:03:42 +0100 > Christian Borntraeger <borntraeger@de.ibm.com> wrote: > >> On 03.02.20 18:12, Cornelia Huck wrote: >>> On Mon, 3 Feb 2020 08:19:22 -0500 >>> Christian Borntraeger <borntraeger@de.ibm.com> wrote: >>> >>>> From: Vasily Gorbik <gor@linux.ibm.com> >>>> >>>> Introduce KVM_S390_PROTECTED_VIRTUALIZATION_HOST kbuild option for >>>> protected virtual machines hosting support code. >>> >>> Hm... I seem to remember that you wanted to drop this config option and >>> always build the code, in order to reduce complexity. Have you >>> reconsidered this? >> >> I am still in favour of removing this, but I did not get an "yes, lets do >> it" answer. Since removing is easier than re-adding its still in. > > ok Any preference from you? [...] > > I think I was confused about different things last time... > > But that is probably a sign that this wants a comment :) Will add to kernel/uv.c /* the bootdata_preserved fields come from ones in arch/s390/boot/uv.c */ to boot/uv.c /* will be used in arch/s390/kernel/uv.c */ [...] > Fair enough; it's just that it's not very clear from the messages in > the log what happened. Maybe > > "prot_virt: Running as protected virtualization guest." > "prot_virt: The ultravisor call facility is not available." > > That at least links back to the kernel parameter. I will defer this until the end, in the hope to have a final name by then.
On Tue, 4 Feb 2020 10:38:55 +0100 Christian Borntraeger <borntraeger@de.ibm.com> wrote: > On 04.02.20 10:28, Cornelia Huck wrote: > > On Mon, 3 Feb 2020 23:03:42 +0100 > > Christian Borntraeger <borntraeger@de.ibm.com> wrote: > > > >> On 03.02.20 18:12, Cornelia Huck wrote: > >>> On Mon, 3 Feb 2020 08:19:22 -0500 > >>> Christian Borntraeger <borntraeger@de.ibm.com> wrote: > >>> > >>>> From: Vasily Gorbik <gor@linux.ibm.com> > >>>> > >>>> Introduce KVM_S390_PROTECTED_VIRTUALIZATION_HOST kbuild option for > >>>> protected virtual machines hosting support code. > >>> > >>> Hm... I seem to remember that you wanted to drop this config option and > >>> always build the code, in order to reduce complexity. Have you > >>> reconsidered this? > >> > >> I am still in favour of removing this, but I did not get an "yes, lets do > >> it" answer. Since removing is easier than re-adding its still in. > > > > ok > > Any preference from you? Not at the moment, I still need to look at the following patches. > > [...] > > > > I think I was confused about different things last time... > > > > But that is probably a sign that this wants a comment :) > > Will add > > to kernel/uv.c > /* the bootdata_preserved fields come from ones in arch/s390/boot/uv.c */ > > to boot/uv.c > /* will be used in arch/s390/kernel/uv.c */ Thanks! > > > [...] > > Fair enough; it's just that it's not very clear from the messages in > > the log what happened. Maybe > > > > "prot_virt: Running as protected virtualization guest." > > "prot_virt: The ultravisor call facility is not available." > > > > That at least links back to the kernel parameter. > > I will defer this until the end, in the hope to have a final name by then. > ok
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index ade4e6ec23e0..327af96f9528 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3750,6 +3750,11 @@ before loading. See Documentation/admin-guide/blockdev/ramdisk.rst. + prot_virt= [S390] enable hosting protected virtual machines + isolated from the hypervisor (if hardware supports + that). + Format: <bool> + psi= [KNL] Enable or disable pressure stall information tracking. Format: <bool> diff --git a/arch/s390/boot/Makefile b/arch/s390/boot/Makefile index e2c47d3a1c89..82247e71617a 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) $(CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST)) += uv.o obj-$(CONFIG_RELOCATABLE) += machine_kexec_reloc.o obj-$(CONFIG_RANDOMIZE_BASE) += kaslr.o targets := bzImage startup.a section_cmp.boot.data section_cmp.boot.preserved.data $(obj-y) diff --git a/arch/s390/boot/uv.c b/arch/s390/boot/uv.c index ed007f4a6444..88cf8825d169 100644 --- a/arch/s390/boot/uv.c +++ b/arch/s390/boot/uv.c @@ -3,7 +3,12 @@ #include <asm/facility.h> #include <asm/sections.h> +#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST int __bootdata_preserved(prot_virt_guest); +#endif +#ifdef CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST +struct uv_info __bootdata_preserved(uv_info); +#endif void uv_query_info(void) { @@ -18,7 +23,20 @@ void uv_query_info(void) if (uv_call(0, (uint64_t)&uvcb)) return; - if (test_bit_inv(BIT_UVC_CMD_SET_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list) && + if (IS_ENABLED(CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST)) { + memcpy(uv_info.inst_calls_list, uvcb.inst_calls_list, sizeof(uv_info.inst_calls_list)); + uv_info.uv_base_stor_len = uvcb.uv_base_stor_len; + uv_info.guest_base_stor_len = uvcb.conf_base_phys_stor_len; + uv_info.guest_virt_base_stor_len = uvcb.conf_base_virt_stor_len; + uv_info.guest_virt_var_stor_len = uvcb.conf_virt_var_stor_len; + uv_info.guest_cpu_stor_len = uvcb.cpu_stor_len; + uv_info.max_sec_stor_addr = ALIGN(uvcb.max_guest_stor_addr, PAGE_SIZE); + uv_info.max_num_sec_conf = uvcb.max_num_sec_conf; + uv_info.max_guest_cpus = uvcb.max_guest_cpus; + } + + if (IS_ENABLED(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) && + test_bit_inv(BIT_UVC_CMD_SET_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list) && test_bit_inv(BIT_UVC_CMD_REMOVE_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list)) prot_virt_guest = 1; } diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h index 4093a2856929..32eac3ab2d3b 100644 --- a/arch/s390/include/asm/uv.h +++ b/arch/s390/include/asm/uv.h @@ -44,7 +44,19 @@ struct uv_cb_qui { struct uv_cb_header header; u64 reserved08; u64 inst_calls_list[4]; - u64 reserved30[15]; + u64 reserved30[2]; + u64 uv_base_stor_len; + u64 reserved48; + u64 conf_base_phys_stor_len; + u64 conf_base_virt_stor_len; + u64 conf_virt_var_stor_len; + u64 cpu_stor_len; + u32 reserved68[3]; + u32 max_num_sec_conf; + u64 max_guest_stor_addr; + u8 reserved80[150-128]; + u16 max_guest_cpus; + u64 reserved98; } __packed __aligned(8); struct uv_cb_share { @@ -69,9 +81,21 @@ static inline int uv_call(unsigned long r1, unsigned long r2) return cc; } -#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST +struct uv_info { + unsigned long inst_calls_list[4]; + unsigned long uv_base_stor_len; + unsigned long guest_base_stor_len; + unsigned long guest_virt_base_stor_len; + unsigned long guest_virt_var_stor_len; + unsigned long guest_cpu_stor_len; + unsigned long max_sec_stor_addr; + unsigned int max_num_sec_conf; + unsigned short max_guest_cpus; +}; +extern struct uv_info uv_info; extern int prot_virt_guest; +#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST static inline int is_prot_virt_guest(void) { return prot_virt_guest; @@ -121,11 +145,27 @@ static inline int uv_remove_shared(unsigned long addr) return share(addr, UVC_CMD_REMOVE_SHARED_ACCESS); } -void uv_query_info(void); #else #define is_prot_virt_guest() 0 static inline int uv_set_shared(unsigned long addr) { return 0; } static inline int uv_remove_shared(unsigned long addr) { return 0; } +#endif + +#ifdef CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST +extern int prot_virt_host; + +static inline int is_prot_virt_host(void) +{ + return prot_virt_host; +} +#else +#define is_prot_virt_host() 0 +#endif + +#if defined(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) || \ + defined(CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST) +void uv_query_info(void); +#else static inline void uv_query_info(void) {} #endif diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile index 2b1203cf7be6..1b958a453e37 100644 --- a/arch/s390/kernel/Makefile +++ b/arch/s390/kernel/Makefile @@ -78,6 +78,7 @@ obj-$(CONFIG_PERF_EVENTS) += perf_cpum_cf_events.o perf_regs.o obj-$(CONFIG_PERF_EVENTS) += perf_cpum_cf_diag.o obj-$(CONFIG_TRACEPOINTS) += trace.o +obj-$(findstring y, $(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) $(CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST)) += uv.o # vdso obj-y += vdso64/ diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index d5fbd754f41a..f2ab2528859f 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -92,10 +92,6 @@ char elf_platform[ELF_PLATFORM_SIZE]; unsigned long int_hwcap = 0; -#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST -int __bootdata_preserved(prot_virt_guest); -#endif - int __bootdata(noexec_disabled); int __bootdata(memory_end_set); unsigned long __bootdata(memory_end); diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c new file mode 100644 index 000000000000..35ce89695509 --- /dev/null +++ b/arch/s390/kernel/uv.c @@ -0,0 +1,48 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Common Ultravisor functions and initialization + * + * Copyright IBM Corp. 2019 + */ +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/sizes.h> +#include <linux/bitmap.h> +#include <linux/memblock.h> +#include <asm/facility.h> +#include <asm/sections.h> +#include <asm/uv.h> + +#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST +int __bootdata_preserved(prot_virt_guest); +#endif + +#ifdef CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST +int prot_virt_host; +EXPORT_SYMBOL(prot_virt_host); +struct uv_info __bootdata_preserved(uv_info); +EXPORT_SYMBOL(uv_info); + +static int __init prot_virt_setup(char *val) +{ + bool enabled; + int rc; + + rc = kstrtobool(val, &enabled); + if (!rc && enabled) + prot_virt_host = 1; + + if (is_prot_virt_guest() && prot_virt_host) { + 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."); + } + + return rc; +} +early_param("prot_virt", prot_virt_setup); +#endif diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig index d3db3d7ed077..9ce9c7295e16 100644 --- a/arch/s390/kvm/Kconfig +++ b/arch/s390/kvm/Kconfig @@ -55,6 +55,25 @@ config KVM_S390_UCONTROL If unsure, say N. +config KVM_S390_PROTECTED_VIRTUALIZATION_HOST + bool "Protected guests execution support" + depends on KVM + help + Support hosting protected virtual machines in KVM. The state + of these machines like memory content or register content is + protected from the host or host administrators. + + Enabling this option will enable extra code that allows a + Linux hypervisor to talk to a new firmware instance called + ultravisor that will take care of protecting the guest while + also enabling KVM to run this guest. + + This feature must be enable via the kernel command line option + prot_virt. + + If unsure, say Y. + + # OK, it's a little counter-intuitive to do this, but it puts it neatly under # the virtualization menu. source "drivers/vhost/Kconfig"