From: David Hildenbrand <david@redhat.com>
To: Christian Borntraeger <borntraeger@de.ibm.com>,
Janosch Frank <frankja@linux.vnet.ibm.com>
Cc: KVM <kvm@vger.kernel.org>, Cornelia Huck <cohuck@redhat.com>,
Thomas Huth <thuth@redhat.com>,
Ulrich Weigand <Ulrich.Weigand@de.ibm.com>,
Claudio Imbrenda <imbrenda@linux.ibm.com>,
linux-s390 <linux-s390@vger.kernel.org>,
Michael Mueller <mimu@linux.ibm.com>,
Vasily Gorbik <gor@linux.ibm.com>
Subject: Re: [PATCH v2 03/42] s390/protvirt: introduce host side setup
Date: Mon, 17 Feb 2020 10:53:41 +0100 [thread overview]
Message-ID: <8b6f790f-8d41-f9a8-1c9c-df900d22fa47@redhat.com> (raw)
In-Reply-To: <20200214222658.12946-4-borntraeger@de.ibm.com>
On 14.02.20 23:26, Christian Borntraeger wrote:
> From: Vasily Gorbik <gor@linux.ibm.com>
>
> 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>
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> [borntraeger@de.ibm.com: patch merging, splitting, fixing]
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> ---
> .../admin-guide/kernel-parameters.txt | 5 ++
> arch/s390/boot/Makefile | 2 +-
> arch/s390/boot/uv.c | 21 +++++++-
> arch/s390/include/asm/uv.h | 45 +++++++++++++++-
> arch/s390/kernel/Makefile | 1 +
> arch/s390/kernel/setup.c | 4 --
> arch/s390/kernel/uv.c | 52 +++++++++++++++++++
> 7 files changed, 122 insertions(+), 8 deletions(-)
> create mode 100644 arch/s390/kernel/uv.c
>
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index dbc22d684627..b0beae9b9e36 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -3795,6 +3795,11 @@
> 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..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) $(CONFIG_PGSTE)) += uv.o
> obj-$(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..af9e1cc93c68 100644
> --- a/arch/s390/boot/uv.c
> +++ b/arch/s390/boot/uv.c
> @@ -3,7 +3,13 @@
> #include <asm/facility.h>
> #include <asm/sections.h>
>
> +/* will be used in arch/s390/kernel/uv.c */
> +#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
> int __bootdata_preserved(prot_virt_guest);
> +#endif
> +#if IS_ENABLED(CONFIG_KVM)
> +struct uv_info __bootdata_preserved(uv_info);
> +#endif
>
> void uv_query_info(void)
> {
> @@ -18,7 +24,20 @@ 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)) {
> + 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..34b1114dcc38 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 reserved70[3];
> + u32 max_num_sec_conf;
> + u64 max_guest_stor_addr;
> + u8 reserved88[158-136];
> + u16 max_guest_cpus;
> + u64 reserveda0;
> } __packed __aligned(8);
>
> struct uv_cb_share {
> @@ -69,6 +81,19 @@ static inline int uv_call(unsigned long r1, unsigned long r2)
> return cc;
> }
>
> +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;
> +
> #ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
> extern int prot_virt_guest;
>
> @@ -121,11 +146,27 @@ 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
> +
> +#if IS_ENABLED(CONFIG_KVM)
> +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) || \
> + IS_ENABLED(CONFIG_KVM)
> +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..22bfb8d5084e 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_PGSTE)) += uv.o
>
> # vdso
> obj-y += vdso64/
> diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
> index b2c2f75860e8..a2496382175e 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..b1f936710360
> --- /dev/null
> +++ b/arch/s390/kernel/uv.c
> @@ -0,0 +1,52 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Common Ultravisor functions and initialization
> + *
> + * Copyright IBM Corp. 2019, 2020
> + */
> +#define KMSG_COMPONENT "prot_virt"
> +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
> +
> +#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>
> +
> +/* the bootdata_preserved fields come from ones in arch/s390/boot/uv.c */
> +#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
> +int __bootdata_preserved(prot_virt_guest);
> +#endif
> +
> +#if IS_ENABLED(CONFIG_KVM)
Why is that glued to CONFIG_KVM? Can't we glue all that stuff to
CONFIG_PROTECTED_VIRTUALIZATION_GUEST and make in kconfig
CONFIG_PROTECTED_VIRTUALIZATION_GUEST depend on CONFIG_KVM?
IOW, I'd prefer to only have CONFIG_PROTECTED_VIRTUALIZATION_GUEST in
!KVM code and enforce it via kconfig instead.
Anyhow, I remember Conny also having a comment about that previously, so
Acked-by: David Hildenbrand <david@redhat.com>
--
Thanks,
David / dhildenb
next prev parent reply other threads:[~2020-02-17 9:53 UTC|newest]
Thread overview: 132+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-14 22:26 [PATCH v2 00/42] KVM: s390: Add support for protected VMs Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 01/42] mm:gup/writeback: add callbacks for inaccessible pages Christian Borntraeger
2020-02-17 9:14 ` David Hildenbrand
2020-02-17 11:10 ` Christian Borntraeger
2020-02-18 8:27 ` David Hildenbrand
2020-02-18 15:46 ` Sean Christopherson
2020-02-18 16:02 ` Will Deacon
2020-02-18 16:15 ` Christian Borntraeger
2020-02-18 21:35 ` Sean Christopherson
2020-02-19 8:31 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 02/42] KVM: s390/interrupt: do not pin adapter interrupt pages Christian Borntraeger
2020-02-17 9:43 ` David Hildenbrand
2020-02-20 12:18 ` David Hildenbrand
2020-02-20 13:31 ` Christian Borntraeger
2020-02-20 13:34 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 03/42] s390/protvirt: introduce host side setup Christian Borntraeger
2020-02-17 9:53 ` David Hildenbrand [this message]
2020-02-17 11:11 ` Christian Borntraeger
2020-02-17 11:13 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 04/42] s390/protvirt: add ultravisor initialization Christian Borntraeger
2020-02-17 9:57 ` David Hildenbrand
2020-02-17 11:13 ` Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 05/42] s390/mm: provide memory management functions for protected KVM guests Christian Borntraeger
2020-02-17 10:21 ` David Hildenbrand
2020-02-17 11:28 ` Christian Borntraeger
2020-02-17 12:07 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 06/42] s390/mm: add (non)secure page access exceptions handlers Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 07/42] KVM: s390: protvirt: Add UV debug trace Christian Borntraeger
2020-02-17 10:41 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 08/42] KVM: s390: add new variants of UV CALL Christian Borntraeger
2020-02-17 10:42 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 09/42] KVM: s390: protvirt: Add initial vm and cpu lifecycle handling Christian Borntraeger
2020-02-17 10:56 ` David Hildenbrand
2020-02-17 12:04 ` Christian Borntraeger
2020-02-17 12:09 ` David Hildenbrand
2020-02-17 14:53 ` [PATCH 0/2] example changes Christian Borntraeger
2020-02-17 14:53 ` [PATCH 1/2] lock changes Christian Borntraeger
2020-02-17 14:53 ` [PATCH 2/2] merge vm/cpu create Christian Borntraeger
2020-02-17 15:00 ` Janosch Frank
2020-02-17 15:02 ` Christian Borntraeger
2020-02-19 11:02 ` Christian Borntraeger
2020-02-17 19:18 ` [PATCH 0/2] example changes David Hildenbrand
2020-02-18 8:09 ` [PATCH v2 09/42] KVM: s390: protvirt: Add initial vm and cpu lifecycle handling Christian Borntraeger
2020-02-18 8:39 ` [PATCH v2.1] " Christian Borntraeger
2020-02-18 9:12 ` David Hildenbrand
2020-02-18 21:18 ` Christian Borntraeger
2020-02-19 8:32 ` David Hildenbrand
2020-02-19 11:01 ` Christian Borntraeger
2020-02-18 9:56 ` David Hildenbrand
2020-02-18 20:26 ` Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 10/42] KVM: s390: protvirt: Add KVM api documentation Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 11/42] KVM: s390: protvirt: Secure memory is not mergeable Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 12/42] KVM: s390/mm: Make pages accessible before destroying the guest Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 13/42] KVM: s390: protvirt: Handle SE notification interceptions Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 14/42] KVM: s390: protvirt: Instruction emulation Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 15/42] KVM: s390: protvirt: Add interruption injection controls Christian Borntraeger
2020-02-17 10:59 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 16/42] KVM: s390: protvirt: Implement interruption injection Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 17/42] KVM: s390: protvirt: Add SCLP interrupt handling Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 18/42] KVM: s390: protvirt: Handle spec exception loops Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 19/42] KVM: s390: protvirt: Add new gprs location handling Christian Borntraeger
2020-02-17 11:01 ` David Hildenbrand
2020-02-17 11:33 ` Christian Borntraeger
2020-02-17 14:37 ` Janosch Frank
2020-02-14 22:26 ` [PATCH v2 20/42] KVM: S390: protvirt: Introduce instruction data area bounce buffer Christian Borntraeger
2020-02-17 11:08 ` David Hildenbrand
2020-02-17 14:47 ` Janosch Frank
2020-02-17 15:00 ` Christian Borntraeger
2020-02-17 15:38 ` Janosch Frank
2020-02-17 16:58 ` Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 21/42] KVM: s390: protvirt: handle secure guest prefix pages Christian Borntraeger
2020-02-17 11:11 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 22/42] KVM: s390/mm: handle guest unpin events Christian Borntraeger
2020-02-17 14:23 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 23/42] KVM: s390: protvirt: Write sthyi data to instruction data area Christian Borntraeger
2020-02-17 14:24 ` David Hildenbrand
2020-02-17 18:40 ` Christian Borntraeger
2020-02-17 19:16 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 24/42] KVM: s390: protvirt: STSI handling Christian Borntraeger
2020-02-18 8:35 ` David Hildenbrand
2020-02-18 8:44 ` Christian Borntraeger
2020-02-18 9:08 ` David Hildenbrand
2020-02-18 9:11 ` Christian Borntraeger
2020-02-18 9:13 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 25/42] KVM: s390: protvirt: disallow one_reg Christian Borntraeger
2020-02-18 8:40 ` David Hildenbrand
2020-02-18 8:57 ` Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 26/42] KVM: s390: protvirt: Do only reset registers that are accessible Christian Borntraeger
2020-02-18 8:42 ` David Hildenbrand
2020-02-18 9:20 ` Christian Borntraeger
2020-02-18 9:28 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 27/42] KVM: s390: protvirt: Only sync fmt4 registers Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 28/42] KVM: s390: protvirt: Add program exception injection Christian Borntraeger
2020-02-18 9:33 ` David Hildenbrand
2020-02-18 9:37 ` Christian Borntraeger
2020-02-18 9:39 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 29/42] KVM: s390: protvirt: Add diag 308 subcode 8 - 10 handling Christian Borntraeger
2020-02-18 9:38 ` David Hildenbrand
2020-02-19 12:45 ` Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 30/42] KVM: s390: protvirt: UV calls in support of diag308 0, 1 Christian Borntraeger
2020-02-18 9:44 ` David Hildenbrand
2020-02-19 11:53 ` Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 31/42] KVM: s390: protvirt: Report CPU state to Ultravisor Christian Borntraeger
2020-02-18 9:48 ` David Hildenbrand
2020-02-19 19:36 ` Christian Borntraeger
2020-02-19 19:46 ` Christian Borntraeger
2020-02-20 10:52 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 32/42] KVM: s390: protvirt: Support cmd 5 operation state Christian Borntraeger
2020-02-18 9:50 ` David Hildenbrand
2020-02-19 11:06 ` Christian Borntraeger
2020-02-19 11:08 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 33/42] KVM: s390: protvirt: Mask PSW interrupt bits for interception 104 and 112 Christian Borntraeger
2020-02-18 9:53 ` David Hildenbrand
2020-02-18 10:02 ` David Hildenbrand
2020-02-18 10:05 ` Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 34/42] KVM: s390: protvirt: do not inject interrupts after start Christian Borntraeger
2020-02-18 9:53 ` David Hildenbrand
2020-02-18 10:02 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 35/42] KVM: s390: protvirt: Add UV cpu reset calls Christian Borntraeger
2020-02-18 9:54 ` David Hildenbrand
2020-02-14 22:26 ` [PATCH v2 36/42] DOCUMENTATION: Protected virtual machine introduction and IPL Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 37/42] s390/uv: Fix handling of length extensions (already in s390 tree) Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 38/42] s390: protvirt: Add sysfs firmware interface for Ultravisor information Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 39/42] example for future extension: mm:gup/writeback: add callbacks for inaccessible pages: error cases Christian Borntraeger
2020-02-18 16:25 ` Will Deacon
2020-02-18 16:30 ` Christian Borntraeger
2020-02-18 16:33 ` Will Deacon
2020-02-14 22:26 ` [PATCH v2 40/42] example for future extension: mm:gup/writeback: add callbacks for inaccessible pages: source indication Christian Borntraeger
2020-02-17 14:15 ` Ulrich Weigand
2020-02-17 14:38 ` Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 41/42] potential fixup for "s390/mm: provide memory management functions for protected KVM guests" Christian Borntraeger
2020-02-14 22:26 ` [PATCH v2 42/42] KVM: s390: rstify new ioctls in api.rst Christian Borntraeger
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