2023-01-22 03:09:42

by Tianyu Lan

[permalink] [raw]
Subject: [RFC PATCH V3 09/16] x86/hyperv: SEV-SNP enlightened guest don't support legacy rtc

From: Tianyu Lan <[email protected]>

SEV-SNP enlightened guest doesn't support legacy rtc. Set
legacy.rtc, x86_platform.set_wallclock and get_wallclock to
0 or noop(). Make get/set_rtc_noop() to be public and reuse
them in the ms_hyperv_init_platform().

Signed-off-by: Tianyu Lan <[email protected]>
---
arch/x86/include/asm/mshyperv.h | 7 ++++++-
arch/x86/include/asm/x86_init.h | 2 ++
arch/x86/kernel/cpu/mshyperv.c | 3 +++
arch/x86/kernel/x86_init.c | 4 ++--
4 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index 1a4af0a4f29a..7266d71d30d6 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -33,6 +33,12 @@ extern bool hv_isolation_type_en_snp(void);

extern union hv_ghcb * __percpu *hv_ghcb_pg;

+/*
+ * Hyper-V puts processor and memory layout info
+ * to this address in SEV-SNP enlightened guest.
+ */
+#define EN_SEV_SNP_PROCESSOR_INFO_ADDR 0x802000
+
int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages);
int hv_call_add_logical_proc(int node, u32 lp_index, u32 acpi_id);
int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags);
@@ -267,7 +273,6 @@ static inline void hv_set_register(unsigned int reg, u64 value) { }
static inline u64 hv_get_register(unsigned int reg) { return 0; }
#endif /* CONFIG_HYPERV */

-
#include <asm-generic/mshyperv.h>

#endif
diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index c1c8c581759d..d8fb3a1639e9 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -326,5 +326,7 @@ extern void x86_init_uint_noop(unsigned int unused);
extern bool bool_x86_init_noop(void);
extern void x86_op_int_noop(int cpu);
extern bool x86_pnpbios_disabled(void);
+extern int set_rtc_noop(const struct timespec64 *now);
+extern void get_rtc_noop(struct timespec64 *now);

#endif
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index b1871a7bb4c9..197c8f2ec4eb 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -508,6 +508,9 @@ static void __init ms_hyperv_init_platform(void)
* bios regions and reserve resources are not
* available. Set these callback to NULL.
*/
+ x86_platform.legacy.rtc = 0;
+ x86_platform.set_wallclock = set_rtc_noop;
+ x86_platform.get_wallclock = get_rtc_noop;
x86_platform.legacy.reserve_bios_regions = x86_init_noop;
x86_init.resources.probe_roms = x86_init_noop;
x86_init.resources.reserve_resources = x86_init_noop;
diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c
index ef80d361b463..d93aeffec19b 100644
--- a/arch/x86/kernel/x86_init.c
+++ b/arch/x86/kernel/x86_init.c
@@ -33,8 +33,8 @@ static int __init iommu_init_noop(void) { return 0; }
static void iommu_shutdown_noop(void) { }
bool __init bool_x86_init_noop(void) { return false; }
void x86_op_int_noop(int cpu) { }
-static __init int set_rtc_noop(const struct timespec64 *now) { return -EINVAL; }
-static __init void get_rtc_noop(struct timespec64 *now) { }
+int set_rtc_noop(const struct timespec64 *now) { return -EINVAL; }
+void get_rtc_noop(struct timespec64 *now) { }

static __initconst const struct of_device_id of_cmos_match[] = {
{ .compatible = "motorola,mc146818" },
--
2.25.1


2023-01-31 14:03:56

by Wei Liu

[permalink] [raw]
Subject: Re: [RFC PATCH V3 09/16] x86/hyperv: SEV-SNP enlightened guest don't support legacy rtc

On Sat, Jan 21, 2023 at 09:45:59PM -0500, Tianyu Lan wrote:
> From: Tianyu Lan <[email protected]>
>
> SEV-SNP enlightened guest doesn't support legacy rtc. Set
> legacy.rtc, x86_platform.set_wallclock and get_wallclock to
> 0 or noop(). Make get/set_rtc_noop() to be public and reuse
> them in the ms_hyperv_init_platform().
>
> Signed-off-by: Tianyu Lan <[email protected]>
> ---
> arch/x86/include/asm/mshyperv.h | 7 ++++++-
> arch/x86/include/asm/x86_init.h | 2 ++
> arch/x86/kernel/cpu/mshyperv.c | 3 +++
> arch/x86/kernel/x86_init.c | 4 ++--
> 4 files changed, 13 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
> index 1a4af0a4f29a..7266d71d30d6 100644
> --- a/arch/x86/include/asm/mshyperv.h
> +++ b/arch/x86/include/asm/mshyperv.h
> @@ -33,6 +33,12 @@ extern bool hv_isolation_type_en_snp(void);
>
> extern union hv_ghcb * __percpu *hv_ghcb_pg;
>
> +/*
> + * Hyper-V puts processor and memory layout info
> + * to this address in SEV-SNP enlightened guest.
> + */
> +#define EN_SEV_SNP_PROCESSOR_INFO_ADDR 0x802000

This hunk should be moved to the previous patch. It is not needed in
this patch.

Thanks,
Wei.

2023-02-02 03:44:17

by Tianyu Lan

[permalink] [raw]
Subject: Re: [RFC PATCH V3 09/16] x86/hyperv: SEV-SNP enlightened guest don't support legacy rtc

On 1/31/2023 10:03 PM, Wei Liu wrote:
>> diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
>> index 1a4af0a4f29a..7266d71d30d6 100644
>> --- a/arch/x86/include/asm/mshyperv.h
>> +++ b/arch/x86/include/asm/mshyperv.h
>> @@ -33,6 +33,12 @@ extern bool hv_isolation_type_en_snp(void);
>>
>> extern union hv_ghcb * __percpu *hv_ghcb_pg;
>>
>> +/*
>> + * Hyper-V puts processor and memory layout info
>> + * to this address in SEV-SNP enlightened guest.
>> + */
>> +#define EN_SEV_SNP_PROCESSOR_INFO_ADDR 0x802000
> This hunk should be moved to the previous patch. It is not needed in
> this patch.

Nice catch. Sorry for noise. Will fix in the next version.

Thanks.