a fatal shutdown during TDX private<=>shared conversion
- Annotate sites where VM "exit reasons" are reused as hypercall
numbers.
-----BEGIN PGP SIGNATURE-----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=Hr3D
-----END PGP SIGNATURE-----
Merge tag 'x86_tdx_for_6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 tdx updates from Dave Hansen:
- Fix a race window where load_unaligned_zeropad() could cause a fatal
shutdown during TDX private<=>shared conversion
The race has never been observed in practice but might allow
load_unaligned_zeropad() to catch a TDX page in the middle of its
conversion process which would lead to a fatal and unrecoverable
guest shutdown.
- Annotate sites where VM "exit reasons" are reused as hypercall
numbers.
* tag 'x86_tdx_for_6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix enc_status_change_finish_noop()
x86/tdx: Fix race between set_memory_encrypted() and load_unaligned_zeropad()
x86/mm: Allow guest.enc_status_change_prepare() to fail
x86/tdx: Wrap exit reason with hcall_func()
Hookup TDX-specific code to accept memory.
Accepting the memory is done with ACCEPT_PAGE module call on every page
in the range. MAP_GPA hypercall is not required as the unaccepted memory
is considered private already.
Extract the part of tdx_enc_status_changed() that does memory acceptance
in a new helper. Move the helper tdx-shared.c. It is going to be used by
both main kernel and decompressor.
[ bp: Fix the INTEL_TDX_GUEST=y, KVM_GUEST=n build. ]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230606142637.5171-10-kirill.shutemov@linux.intel.com
Memory acceptance requires a hypercall and one or multiple module calls.
Make helpers for the calls available in boot stub. It has to accept
memory where kernel image and initrd are placed.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20230606142637.5171-8-kirill.shutemov@linux.intel.com
TDX reuses VMEXIT "reasons" in its guest->host hypercall ABI. This is
confusing because there might not be a VMEXIT involved at *all*.
These instances are supposed to document situation and reduce confusion
by wrapping VMEXIT reasons with hcall_func().
The decompression code does not follow this convention.
Unify the TDX decompression code with the other TDX use of VMEXIT reasons.
No functional changes.
Signed-off-by: Nikolay Borisov <nik.borisov@suse.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: https://lore.kernel.org/all/20230505120332.1429957-1-nik.borisov%40suse.com
After TDX_HCALL_ISSUE_STI got dropped, the only flag left is
TDX_HCALL_HAS_OUTPUT. The flag indicates if the caller wants to see
tdx_hypercall_args updated based on the hypercall output.
Drop the flags and provide __tdx_hypercall_ret() that matches
TDX_HCALL_HAS_OUTPUT semantics.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/20230321003511.9469-1-kirill.shutemov%40linux.intel.com
- Prevent unexpected #VE's from:
- Hosts removing perfectly good guest mappings (SEPT_VE_DISABLE
- Excessive #VE notifications (NOTIFY_ENABLES) which are
delivered via a #VE.
-----BEGIN PGP SIGNATURE-----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=UpyL
-----END PGP SIGNATURE-----
Merge tag 'x86_tdx_for_6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull Intel Trust Domain Extensions (TDX) updates from Dave Hansen:
"Other than a minor fixup, the content here is to ensure that TDX
guests never see virtualization exceptions (#VE's) that might be
induced by the untrusted VMM.
This is a highly desirable property. Without it, #VE exception
handling would fall somewhere between NMIs, machine checks and total
insanity. With it, #VE handling remains pretty mundane.
Summary:
- Fixup comment typo
- Prevent unexpected #VE's from:
- Hosts removing perfectly good guest mappings (SEPT_VE_DISABLE)
- Excessive #VE notifications (NOTIFY_ENABLES) which are delivered
via a #VE"
* tag 'x86_tdx_for_6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tdx: Do not corrupt frame-pointer in __tdx_hypercall()
x86/tdx: Disable NOTIFY_ENABLES
x86/tdx: Relax SEPT_VE_DISABLE check for debug TD
x86/tdx: Use ReportFatalError to report missing SEPT_VE_DISABLE
x86/tdx: Expand __tdx_hypercall() to handle more arguments
x86/tdx: Refactor __tdx_hypercall() to allow pass down more arguments
x86/tdx: Add more registers to struct tdx_hypercall_args
x86/tdx: Fix typo in comment in __tdx_hypercall()
struct tdx_hypercall_args is used to pass down hypercall arguments to
__tdx_hypercall() assembly routine.
Currently __tdx_hypercall() handles up to 6 arguments. In preparation to
changes in __tdx_hypercall(), expand the structure to 6 more registers
and generate asm offsets for them.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20230126221159.8635-3-kirill.shutemov%40linux.intel.com
Now that arch_cpu_idle() is expected to return with IRQs disabled,
avoid the useless STI/CLI dance.
Per the specs this is supposed to work, but nobody has yet relied up
this behaviour so broken implementations are possible.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195540.682137572@infradead.org
This is the Intel version of a confidential computing solution called
Trust Domain Extensions (TDX). This series adds support to run the
kernel as part of a TDX guest. It provides similar guest protections to
AMD's SEV-SNP like guest memory and register state encryption, memory
integrity protection and a lot more.
Design-wise, it differs from AMD's solution considerably: it uses
a software module which runs in a special CPU mode called (Secure
Arbitration Mode) SEAM. As the name suggests, this module serves as sort
of an arbiter which the confidential guest calls for services it needs
during its lifetime.
Just like AMD's SNP set, this series reworks and streamlines certain
parts of x86 arch code so that this feature can be properly accomodated.
-----BEGIN PGP SIGNATURE-----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=ac9K
-----END PGP SIGNATURE-----
Merge tag 'x86_tdx_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull Intel TDX support from Borislav Petkov:
"Intel Trust Domain Extensions (TDX) support.
This is the Intel version of a confidential computing solution called
Trust Domain Extensions (TDX). This series adds support to run the
kernel as part of a TDX guest. It provides similar guest protections
to AMD's SEV-SNP like guest memory and register state encryption,
memory integrity protection and a lot more.
Design-wise, it differs from AMD's solution considerably: it uses a
software module which runs in a special CPU mode called (Secure
Arbitration Mode) SEAM. As the name suggests, this module serves as
sort of an arbiter which the confidential guest calls for services it
needs during its lifetime.
Just like AMD's SNP set, this series reworks and streamlines certain
parts of x86 arch code so that this feature can be properly
accomodated"
* tag 'x86_tdx_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
x86/tdx: Fix RETs in TDX asm
x86/tdx: Annotate a noreturn function
x86/mm: Fix spacing within memory encryption features message
x86/kaslr: Fix build warning in KASLR code in boot stub
Documentation/x86: Document TDX kernel architecture
ACPICA: Avoid cache flush inside virtual machines
x86/tdx/ioapic: Add shared bit for IOAPIC base address
x86/mm: Make DMA memory shared for TD guest
x86/mm/cpa: Add support for TDX shared memory
x86/tdx: Make pages shared in ioremap()
x86/topology: Disable CPU online/offline control for TDX guests
x86/boot: Avoid #VE during boot for TDX platforms
x86/boot: Set CR0.NE early and keep it set during the boot
x86/acpi/x86/boot: Add multiprocessor wake-up support
x86/boot: Add a trampoline for booting APs via firmware handoff
x86/tdx: Wire up KVM hypercalls
x86/tdx: Port I/O: Add early boot support
x86/tdx: Port I/O: Add runtime hypercalls
x86/boot: Port I/O: Add decompression-time support for TDX
x86/boot: Port I/O: Allow to hook up alternative helpers
...
Port I/O instructions trigger #VE in the TDX environment. In response to
the exception, kernel emulates these instructions using hypercalls.
But during early boot, on the decompression stage, it is cumbersome to
deal with #VE. It is cleaner to go to hypercalls directly, bypassing #VE
handling.
Hook up TDX-specific port I/O helpers if booting in TDX environment.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20220405232939.73860-17-kirill.shutemov@linux.intel.com
There are two implementations of port I/O helpers: one in the kernel and
one in the boot stub.
Move the helpers required for both to <asm/shared/io.h> and use the one
implementation everywhere.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20220405232939.73860-15-kirill.shutemov@linux.intel.com
The early decompression code does port I/O for its console output. But,
handling the decompression-time port I/O demands a different approach
from normal runtime because the IDT required to support #VE based port
I/O emulation is not yet set up. Paravirtualizing I/O calls during
the decompression step is acceptable because the decompression code
doesn't have a lot of call sites to IO instruction.
To support port I/O in decompression code, TDX must be detected before
the decompression code might do port I/O. Detect whether the kernel runs
in a TDX guest.
Add an early_is_tdx_guest() interface to query the cached TDX guest
status in the decompression code.
TDX is detected with CPUID. Make cpuid_count() accessible outside
boot/cpuflags.c.
TDX detection in the main kernel is very similar. Move common bits
into <asm/shared/tdx.h>.
The actual port I/O paravirtualization will come later in the series.
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20220405232939.73860-13-kirill.shutemov@linux.intel.com
The current set of helpers used throughout the run-time kernel have
dependencies on code/facilities outside of the boot kernel, so there
are a number of call-sites throughout the boot kernel where inline
assembly is used instead. More will be added with subsequent patches
that add support for SEV-SNP, so take the opportunity to provide a basic
set of helpers that can be used by the boot kernel to reduce reliance on
inline assembly.
Use boot_* prefix so that it's clear these are helpers specific to the
boot kernel to avoid any confusion with the various other MSR read/write
helpers.
[ bp: Disambiguate parameter names and trim comment. ]
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220307213356.2797205-6-brijesh.singh@amd.com
