Re: [PATCH] x86/tdx: Enhance code generation for TDCALL and SEAMCALL wrappers

On Mon, Jun 03, 2024 at 06:37:45AM -0700, Dave Hansen wrote: > On 6/2/24 04:54, Kirill A. Shutemov wrote: > > Sean observed that the compiler is generating inefficient code to clear > > the tdx_module_args struct for TDCALL and SEAMCALL wrappers. The > > compiler i

[PATCH] x86/tdx: Enhance code generation for TDCALL and SEAMCALL wrappers

grow/shrink: 3/22 up/down: 17/-313 (-296) GCC tends to generate string instructions more frequently to clear the struct. Signed-off-by: Kirill A. Shutemov Suggested-by: Dave Hansen Cc: Sean Christopherson --- arch/x86/boot/compressed/tdx.c| 32 --- arch/x86/coco/tdx/tdx-shared.c

Re: [RFC PATCH] clocksource: hyper-v: Enable the tsc_page for a TDX VM in TD mode

; when > Hyper-V TSC page is not enabled, hv_read_reference_counter defaults to > be drivers/hv/hv_common.c: __hv_read_ref_counter(), which is suboptimal > as it uses the slow MSR interface to get the time info. Why can't the guest just read the TSC directly? Why do we need the page? I am confused. -- Kiryl Shutsemau / Kirill A. Shutemov

Re: [PATCH 16/20] x86/tdx: Convert VP_INFO tdcall to use new TDCALL_5() macro

On Fri, May 17, 2024 at 08:57:10AM -0700, Dave Hansen wrote: > On 5/17/24 07:19, Kirill A. Shutemov wrote: > > - /* > > -* TDINFO TDX module call is used to get the TD execution environment > > -* information like GPA width, number of available vcpus, debug mode &

Re: [PATCH 02/20] x86/tdx: Add macros to generate TDVMCALL wrappers

On Fri, May 17, 2024 at 06:54:15PM +0200, Paolo Bonzini wrote: > On 5/17/24 16:19, Kirill A. Shutemov wrote: > > Introduce a set of macros that allow to generate wrappers for TDVMCALL > > leafs. The macros uses tdvmcall_trmapoline() and provides SYSV-complaint > > ABI on top o

Re: [PATCH 01/20] x86/tdx: Introduce tdvmcall_trampoline()

On Fri, May 17, 2024 at 07:02:25PM +0200, Paolo Bonzini wrote: > On 5/17/24 16:19, Kirill A. Shutemov wrote: > > The function will be used from inline assembly to handle most TDVMCALL > > cases. > > Perhaps add that the calling convention is designed to allow using the asm &g

Re: [PATCH 01/20] x86/tdx: Introduce tdvmcall_trampoline()

On Fri, May 17, 2024 at 08:21:37AM -0700, Dave Hansen wrote: > On 5/17/24 07:19, Kirill A. Shutemov wrote: > > TDCALL calls are centralized into a few megawrappers that take the > > struct tdx_module_args as input. Most of the call sites only use a few > > arguments, but

[PATCH 20/20] x86/tdx: Remove old TDCALL wrappers

All code has been converted to new TDCALL wrappers. Drop the old wrappers. Signed-off-by: Kirill A. Shutemov --- arch/x86/boot/compressed/tdx.c| 6 arch/x86/coco/tdx/tdcall.S| 60 ++- arch/x86/coco/tdx/tdx-shared.c| 20 --- arch/x86

[PATCH 17/20] x86/tdx: Convert VM_RD/VM_WR tdcalls to use new TDCALL macros

on tdx_early_init() is code reduction. Signed-off-by: Kirill A. Shutemov --- arch/x86/coco/tdx/tdx.c | 18 ++ 1 file changed, 2 insertions(+), 16 deletions(-) diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c index e1849878f3bc..6559f3842f67 100644 --- a/arch/x86/coco/tdx

[PATCH 19/20] x86/tdx: Convert MR_REPORT tdcall to use new TDCALL_0() macro

Use newly introduced TDCALL_0() instead of tdcall() to issue MR_REPORT tdcall. It cuts code bloat substantially: Function old new delta tdx_mcall_get_report0229 111-118 Signed-off-by: Kirill A. Shutemov --- arch/x86

[PATCH 18/20] x86/tdx: Convert VP_VEINFO_GET tdcall to use new TDCALL_5() macro

Use newly introduced TDCALL_5() instead of tdcall() to issue VP_VEINFO_GET tdcall. It cuts code bloat substantially: Function old new delta tdx_get_ve_info 253 116-137 Signed-off-by: Kirill A. Shutemov --- arch/x86

[PATCH 16/20] x86/tdx: Convert VP_INFO tdcall to use new TDCALL_5() macro

Use newly introduced TDCALL_5() instead of tdcall() to issue VP_INFO tdcall. It cuts code bloat slightly: Function old new delta tdx_early_init 780 744 -36 Signed-off-by: Kirill A. Shutemov --- arch/x86/coco/tdx

[PATCH 15/20] x86/tdx: Convert PAGE_ACCEPT tdcall to use new TDCALL_0() macro

Use newly introduced TDCALL_0() instead of __tdcall() to issue PAGE_ACCEPT tdcall. It cuts code bloat substantially: Function old new delta tdx_accept_memory592 233-359 Signed-off-by: Kirill A. Shutemov --- arch/x86

[PATCH 08/20] x86/tdx: Convert MMIO handling to use new TDVMCALL macros

Use newly introduced TDVMCALL_0() and TDVMCALL_1() instead of __tdx_hypercall() to handle MMIO emulation. It cuts code bloat substantially: Function old new delta tdx_handle_virt_exception 17471383-364 Signed-off-by: Kirill

[PATCH 12/20] x86/tdx: Rewrite tdx_kvm_hypercall() without __tdx_hypercall()

-by: Kirill A. Shutemov --- arch/x86/coco/tdx/tdx.c | 16 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c index b7299e668564..e7ffe1cd6d32 100644 --- a/arch/x86/coco/tdx/tdx.c +++ b/arch/x86/coco/tdx/tdx.c @@ -49,15

[PATCH 11/20] x86/tdx: Rewrite tdx_panic() without __tdx_hypercall()

the hypercall directly in assembly. It cuts code bloat substantially: Function old new delta tdx_panic222 59-163 Signed-off-by: Kirill A. Shutemov --- arch/x86/coco/tdx/tdcall.S | 28

[PATCH 14/20] x86/tdx: Add macros to generate TDCALL wrappers

Introduce a set of macros that allow to generate wrappers for TDCALL leafs. There are three macros differentiated by number of return parameters. Signed-off-by: Kirill A. Shutemov --- arch/x86/include/asm/shared/tdx.h | 58 +++ 1 file changed, 58 insertions(+) diff

[PATCH 09/20] x86/tdx: Convert MAP_GPA hypercall to use new TDVMCALL macros

645 530-115 tdx_enc_status_change_prepare326 181-145 Total: Before=5553, After=5183, chg -6.66% Signed-off-by: Kirill A. Shutemov --- arch/x86/coco/tdx/tdx.c | 12 +++- 1 file changed, 3 insertions(+), 9 deletions(-) diff --git a/arch/x86/coco/tdx

[PATCH 07/20] x86/tdx: Convert CPUID handling to use new TDVMCALL_4()

Use newly introduced TDVMCALL_4() instead of __tdx_hypercall() to handle CPUID instruction emulation. It cuts code bloat substantially: Function old new delta tdx_handle_virt_exception 18191747 -72 Signed-off-by: Kirill

[PATCH 13/20] x86/tdx: Rewrite hv_tdx_hypercall() without __tdx_hypercall()

old new delta hv_tdx_hypercall 171 42-129 Signed-off-by: Kirill A. Shutemov --- arch/x86/coco/tdx/tdcall.S | 30 ++ arch/x86/hyperv/ivm.c | 14 -- 2 files changed, 30 insertions(+), 14

[PATCH 10/20] x86/tdx: Convert GET_QUOTE hypercall to use new TDVMCALL macros

Use newly introduced TDVMCALL_0() instead of __tdx_hypercall() to issue GET_QUOTE hypercall. It cuts code bloat substantially: Function old new delta tdx_hcall_get_quote 188 76-112 Signed-off-by: Kirill A. Shutemov

[PATCH 05/20] x86/tdx: Convert MSR read handling to use new TDVMCALL_1()

Use newly introduced TDVMCALL_1() instead of __tdx_hypercall() to handle MSR read emulation. It cuts code bloat substantially: Function old new delta tdx_handle_virt_exception 20521947-105 Signed-off-by: Kirill A. Shutemov

[PATCH 01/20] x86/tdx: Introduce tdvmcall_trampoline()

: dozens of instructions per call site to clear unused fields of the structure. This issue can be avoided by using more targeted wrappers. tdvmcall_trampoline() provides a common base for them. The function will be used from inline assembly to handle most TDVMCALL cases. Signed-off-by: Kirill

[PATCH 06/20] x86/tdx: Convert MSR write handling to use new TDVMCALL_0()

Use newly introduced TDVMCALL_0() instead of __tdx_hypercall() to handle MSR write emulation. It cuts code bloat substantially: Function old new delta tdx_handle_virt_exception 19471819-128 Signed-off-by: Kirill A. Shutemov

[PATCH 02/20] x86/tdx: Add macros to generate TDVMCALL wrappers

Introduce a set of macros that allow to generate wrappers for TDVMCALL leafs. The macros uses tdvmcall_trmapoline() and provides SYSV-complaint ABI on top of it. There are three macros differentiated by number of return parameters. Signed-off-by: Kirill A. Shutemov --- arch/x86/include/asm

[PATCH 03/20] x86/tdx: Convert port I/O handling to use new TDVMCALL macros

-by: Kirill A. Shutemov --- arch/x86/boot/compressed/tdx.c| 26 +++--- arch/x86/coco/tdx/tdx.c | 23 +++ arch/x86/include/asm/shared/tdx.h | 4 3 files changed, 18 insertions(+), 35 deletions(-) diff --git a/arch/x86/boot/compressed/tdx.c b/arch

[PATCH 04/20] x86/tdx: Convert HLT handling to use new TDVMCALL_0()

20232052 +29 __pfx___halt 16 - -16 __halt 171 --171 Total: Before=6350, After=6222, chg -2.02% Signed-off-by: Kirill A. Shutemov --- arch/x86/coco/tdx/tdx.c | 29

[PATCH 00/20] x86/tdx: Rewrite TDCALL wrappers

: 212/-3502 (-3290) Please take a look. I would appreciate any feedback. Kirill A. Shutemov (20): x86/tdx: Introduce tdvmcall_trampoline() x86/tdx: Add macros to generate TDVMCALL wrappers x86/tdx: Convert port I/O handling to use new TDVMCALL macros x86/tdx: Convert HLT handling to use new

Re: [PATCH 0/5] Handle set_memory_XXcrypted() errors in Hyper-V

-- > drivers/net/hyperv/netvsc.c | 7 +-- > drivers/uio/uio_hv_generic.c | 12 > include/linux/hyperv.h | 1 + > 5 files changed, 33 insertions(+), 14 deletions(-) Acked-by: Kirill A. Shutemov -- Kiryl Shutsemau / Kirill A. Shutemov

Re: [PATCH v1 1/3] x86/tdx: Check for TDX partitioning during early TDX init

th an > L1 specific > protocol and TDVMCALLs are routed to L0 for performance reasons. It can't be > done > transparently with TDX 1.5 calls alone and we already have TDX 1.5 deployed > to users with > an upstream kernel. TDX 1.5 is not set in stone (yet). The spec is still draft. We can add capabilities if we make case for them. Let's try to shift the discussion to how to make TDX better rather than adding workaround to kernel. -- Kiryl Shutsemau / Kirill A. Shutemov

Re: [PATCH v1 1/3] x86/tdx: Check for TDX partitioning during early TDX init

On Wed, Dec 06, 2023 at 06:49:11PM +0100, Jeremi Piotrowski wrote: > On 05/12/2023 11:54, Kirill A. Shutemov wrote: > > On Mon, Dec 04, 2023 at 08:07:38PM +0100, Jeremi Piotrowski wrote: > >> On 04/12/2023 10:17, Reshetova, Elena wrote: > >>>> Check for additional

Re: [PATCH v1 1/3] x86/tdx: Check for TDX partitioning during early TDX init

> describing that: the kernel already supports, has an implementation that > works and > has actual users. This is also a model that Intel intentionally created the > TD-partitioning > spec to support. > > So lets work together to make X86_FEATURE_TDX_GUEST match reality. I think the right direction is to make TDX architecture good enough without that. If we need more hooks in TDX module that give required control to L1, let's do that. (I don't see it so far) -- Kiryl Shutsemau / Kirill A. Shutemov

Re: [PATCH v1 1/3] x86/tdx: Check for TDX partitioning during early TDX init

On Fri, Nov 24, 2023 at 12:04:56PM +0100, Jeremi Piotrowski wrote: > On 24/11/2023 11:43, Kirill A. Shutemov wrote: > > On Fri, Nov 24, 2023 at 11:31:44AM +0100, Jeremi Piotrowski wrote: > >> On 23/11/2023 14:58, Kirill A. Shutemov wrote: > >>> On Wed, Nov 22, 20

Re: [PATCH v1 1/3] x86/tdx: Check for TDX partitioning during early TDX init

On Fri, Nov 24, 2023 at 11:31:44AM +0100, Jeremi Piotrowski wrote: > On 23/11/2023 14:58, Kirill A. Shutemov wrote: > > On Wed, Nov 22, 2023 at 06:01:04PM +0100, Jeremi Piotrowski wrote: > >> Check for additional CPUID bits to identify TDX guests running with Trust > >&g

Re: [PATCH v1 2/3] x86/coco: Disable TDX module calls when TD partitioning is active

not have access to > TDX module calls. The kernel still has access to TDVMCALL(0) which is > forwarded > to the VMM for processing, which is the L1 TD VM in this case. Sounds like a problem introduced by patch 1/3 :/ -- Kiryl Shutsemau / Kirill A. Shutemov

Re: [PATCH v1 3/3] x86/tdx: Provide stub tdx_accept_memory() for non-TDX configs

efined because the > branch that references tdx_accept_memory() was being discarded due to > DISABLE_TDX_GUEST being set. And who unsets it now? -- Kiryl Shutsemau / Kirill A. Shutemov

Re: [PATCH v1 1/3] x86/tdx: Check for TDX partitioning during early TDX init

we aren't guaranteed access to TDX module calls. I don't follow. The idea of partitioning is that L2 OS can be unenlightened and have no idea if it runs indide of TD. But this patch tries to enumerate TDX anyway. Why? -- Kiryl Shutsemau / Kirill A. Shutemov