Merge tag 'v6.6.24' into dev-6.6

This is the 6.6.24 stable release

x86/sev: Skip ROM range scans and validation for SEV-SNP guests

commit 0f4a1e80989aca185d955fcd791d7750082044a2 upstream.

SEV-SNP requires encrypted memory to be validated before access.
Because th

x86/sev: Skip ROM range scans and validation for SEV-SNP guests

commit 0f4a1e80989aca185d955fcd791d7750082044a2 upstream.

SEV-SNP requires encrypted memory to be validated before access.
Because the ROM memory range is not part of the e820 table, it is not
pre-validated by the BIOS. Therefore, if a SEV-SNP guest kernel wishes
to access this range, the guest must first validate the range.

The current SEV-SNP code does indeed scan the ROM range during early
boot and thus attempts to validate the ROM range in probe_roms().
However, this behavior is neither sufficient nor necessary for the
following reasons:

* With regards to sufficiency, if EFI_CONFIG_TABLES are not enabled and
CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK is set, the kernel will
attempt to access the memory at SMBIOS_ENTRY_POINT_SCAN_START (which
falls in the ROM range) prior to validation.

For example, Project Oak Stage 0 provides a minimal guest firmware
that currently meets these configuration conditions, meaning guests
booting atop Oak Stage 0 firmware encounter a problematic call chain
during dmi_setup() -> dmi_scan_machine() that results in a crash
during boot if SEV-SNP is enabled.

* With regards to necessity, SEV-SNP guests generally read garbage
(which changes across boots) from the ROM range, meaning these scans
are unnecessary. The guest reads garbage because the legacy ROM range
is unencrypted data but is accessed via an encrypted PMD during early
boot (where the PMD is marked as encrypted due to potentially mapping
actually-encrypted data in other PMD-contained ranges).

In one exceptional case, EISA probing treats the ROM range as
unencrypted data, which is inconsistent with other probing.

Continuing to allow SEV-SNP guests to use garbage and to inconsistently
classify ROM range encryption status can trigger undesirable behavior.
For instance, if garbage bytes appear to be a valid signature, memory
may be unnecessarily reserved for the ROM range. Future code or other
use cases may result in more problematic (arbitrary) behavior that
should be avoided.

While one solution would be to overhaul the early PMD mapping to always
treat the ROM region of the PMD as unencrypted, SEV-SNP guests do not
currently rely on data from the ROM region during early boot (and even
if they did, they would be mostly relying on garbage data anyways).

As a simpler solution, skip the ROM range scans (and the otherwise-
necessary range validation) during SEV-SNP guest early boot. The
potential SEV-SNP guest crash due to lack of ROM range validation is
thus avoided by simply not accessing the ROM range.

In most cases, skip the scans by overriding problematic x86_init
functions during sme_early_init() to SNP-safe variants, which can be
likened to x86_init overrides done for other platforms (ex: Xen); such
overrides also avoid the spread of cc_platform_has() checks throughout
the tree.

In the exceptional EISA case, still use cc_platform_has() for the
simplest change, given (1) checks for guest type (ex: Xen domain status)
are already performed here, and (2) these checks occur in a subsys
initcall instead of an x86_init function.

[ bp: Massage commit message, remove "we"s. ]

Fixes: 9704c07bf9f7 ("x86/kernel: Validate ROM memory before accessing when SEV-SNP is active")
Signed-off-by: Kevin Loughlin <kevinloughlin@google.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20240313121546.2964854-1-kevinloughlin@google.com
Signed-off-by: Kevin Loughlin <kevinloughlin@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Merge tag 'v6.6.7' into dev-6.6

This is the 6.6.7 stable release

x86/coco: Disable 32-bit emulation by default on TDX and SEV

[ upstream commit b82a8dbd3d2f4563156f7150c6f2ecab6e960b30 ]

The INT 0x80 instruction is used for 32-bit x86 Linux syscalls. The
kernel

x86/coco: Disable 32-bit emulation by default on TDX and SEV

[ upstream commit b82a8dbd3d2f4563156f7150c6f2ecab6e960b30 ]

The INT 0x80 instruction is used for 32-bit x86 Linux syscalls. The
kernel expects to receive a software interrupt as a result of the INT
0x80 instruction. However, an external interrupt on the same vector
triggers the same handler.

The kernel interprets an external interrupt on vector 0x80 as a 32-bit
system call that came from userspace.

A VMM can inject external interrupts on any arbitrary vector at any
time. This remains true even for TDX and SEV guests where the VMM is
untrusted.

Put together, this allows an untrusted VMM to trigger int80 syscall
handling at any given point. The content of the guest register file at
that moment defines what syscall is triggered and its arguments. It
opens the guest OS to manipulation from the VMM side.

Disable 32-bit emulation by default for TDX and SEV. User can override
it with the ia32_emulation=y command line option.

[ dhansen: reword the changelog ]

Reported-by: Supraja Sridhara <supraja.sridhara@inf.ethz.ch>
Reported-by: Benedict Schlüter <benedict.schlueter@inf.ethz.ch>
Reported-by: Mark Kuhne <mark.kuhne@inf.ethz.ch>
Reported-by: Andrin Bertschi <andrin.bertschi@inf.ethz.ch>
Reported-by: Shweta Shinde <shweta.shinde@inf.ethz.ch>
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>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@vger.kernel.org> # 6.0+: 1da5c9b x86: Introduce ia32_enabled()
Cc: <stable@vger.kernel.org> # 6.0+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Merge drm/drm-fixes into drm-misc-fixes

Forwarding to v6.6-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge branch 'next' into for-linus

Prepare input updates for 6.6 merge window.

Merge tag 'x86_sev_for_v6.6_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 SEV updates from Borislav Petkov:

- Handle the case where the beginning virtual address of the ad

Merge tag 'x86_sev_for_v6.6_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 SEV updates from Borislav Petkov:

- Handle the case where the beginning virtual address of the address
range whose SEV encryption status needs to change, is not page
aligned so that callers which round up the number of pages to be
decrypted, would mark a trailing page as decrypted and thus cause
corruption during live migration.

- Return an error from the #VC handler on AMD SEV-* guests when the
debug registers swapping is enabled as a DR7 access should not happen
then - that register is guest/host switched.

* tag 'x86_sev_for_v6.6_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/sev: Make enc_dec_hypercall() accept a size instead of npages
x86/sev: Do not handle #VC for DR7 read/write

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x86/sev: Make enc_dec_hypercall() accept a size instead of npages

enc_dec_hypercall() accepted a page count instead of a size, which
forced its callers to round up. As a result, non-page aligned
vad

x86/sev: Make enc_dec_hypercall() accept a size instead of npages

enc_dec_hypercall() accepted a page count instead of a size, which
forced its callers to round up. As a result, non-page aligned
vaddrs caused pages to be spuriously marked as decrypted via the
encryption status hypercall, which in turn caused consistent
corruption of pages during live migration. Live migration requires
accurate encryption status information to avoid migrating pages
from the wrong perspective.

Fixes: 064ce6c550a0 ("mm: x86: Invoke hypercall when page encryption status is changed")
Signed-off-by: Steve Rutherford <srutherford@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com>
Tested-by: Ben Hillier <bhillier@google.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230824223731.2055016-1-srutherford@google.com

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Merge drm/drm-next into drm-intel-next

Catching-up with drm-next and drm-intel-gt-next.
It will unblock a code refactor around the platform
definitions (names vs acronyms).

Signed-off-by: Rodrigo V

Merge drm/drm-next into drm-intel-next

Catching-up with drm-next and drm-intel-gt-next.
It will unblock a code refactor around the platform
definitions (names vs acronyms).

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

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Merge drm/drm-next into drm-intel-gt-next

Need to pull in b3e4aae612ec ("drm/i915/hdcp: Modify hdcp_gsc_message msg sending mechanism") as
a dependency for https://patchwork.freedesktop.org/series/1

Merge drm/drm-next into drm-intel-gt-next

Need to pull in b3e4aae612ec ("drm/i915/hdcp: Modify hdcp_gsc_message msg sending mechanism") as
a dependency for https://patchwork.freedesktop.org/series/121735/

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

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Merge drm/drm-next into drm-misc-next

Backmerging to get v6.5-rc2.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge tag 'v6.4' into next

Sync up with mainline to bring in updates to shared infrastructure.

ASoC: Merge v6.5-rc2

Get a similar baseline to my other branches, and fixes for people using
the branch.

Merge v6.5-rc1 into drm-misc-fixes

Boris needs 6.5-rc1 in drm-misc-fixes to prevent a conflict.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

Merge branch 'master' into mm-hotfixes-stable

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

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()

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Merge tag 'smp-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull SMP updates from Thomas Gleixner:
"A large update for SMP management:

- Parallel CPU bringup

Merge tag 'smp-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull SMP updates from Thomas Gleixner:
"A large update for SMP management:

- Parallel CPU bringup

The reason why people are interested in parallel bringup is to
shorten the (kexec) reboot time of cloud servers to reduce the
downtime of the VM tenants.

The current fully serialized bringup does the following per AP:

1) Prepare callbacks (allocate, intialize, create threads)
2) Kick the AP alive (e.g. INIT/SIPI on x86)
3) Wait for the AP to report alive state
4) Let the AP continue through the atomic bringup
5) Let the AP run the threaded bringup to full online state

There are two significant delays:

#3 The time for an AP to report alive state in start_secondary()
on x86 has been measured in the range between 350us and 3.5ms
depending on vendor and CPU type, BIOS microcode size etc.

#4 The atomic bringup does the microcode update. This has been
measured to take up to ~8ms on the primary threads depending
on the microcode patch size to apply.

On a two socket SKL server with 56 cores (112 threads) the boot CPU
spends on current mainline about 800ms busy waiting for the APs to
come up and apply microcode. That's more than 80% of the actual
onlining procedure.

This can be reduced significantly by splitting the bringup
mechanism into two parts:

1) Run the prepare callbacks and kick the AP alive for each AP
which needs to be brought up.

The APs wake up, do their firmware initialization and run the
low level kernel startup code including microcode loading in
parallel up to the first synchronization point. (#1 and #2
above)

2) Run the rest of the bringup code strictly serialized per CPU
(#3 - #5 above) as it's done today.

Parallelizing that stage of the CPU bringup might be possible
in theory, but it's questionable whether required surgery
would be justified for a pretty small gain.

If the system is large enough the first AP is already waiting at
the first synchronization point when the boot CPU finished the
wake-up of the last AP. That reduces the AP bringup time on that
SKL from ~800ms to ~80ms, i.e. by a factor ~10x.

The actual gain varies wildly depending on the system, CPU,
microcode patch size and other factors. There are some
opportunities to reduce the overhead further, but that needs some
deep surgery in the x86 CPU bringup code.

For now this is only enabled on x86, but the core functionality
obviously works for all SMP capable architectures.

- Enhancements for SMP function call tracing so it is possible to
locate the scheduling and the actual execution points. That allows
to measure IPI delivery time precisely"

* tag 'smp-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits)
trace,smp: Add tracepoints for scheduling remotelly called functions
trace,smp: Add tracepoints around remotelly called functions
MAINTAINERS: Add CPU HOTPLUG entry
x86/smpboot: Fix the parallel bringup decision
x86/realmode: Make stack lock work in trampoline_compat()
x86/smp: Initialize cpu_primary_thread_mask late
cpu/hotplug: Fix off by one in cpuhp_bringup_mask()
x86/apic: Fix use of X{,2}APIC_ENABLE in asm with older binutils
x86/smpboot/64: Implement arch_cpuhp_init_parallel_bringup() and enable it
x86/smpboot: Support parallel startup of secondary CPUs
x86/smpboot: Implement a bit spinlock to protect the realmode stack
x86/apic: Save the APIC virtual base address
cpu/hotplug: Allow "parallel" bringup up to CPUHP_BP_KICK_AP_STATE
x86/apic: Provide cpu_primary_thread mask
x86/smpboot: Enable split CPU startup
cpu/hotplug: Provide a split up CPUHP_BRINGUP mechanism
cpu/hotplug: Reset task stack state in _cpu_up()
cpu/hotplug: Remove unused state functions
riscv: Switch to hotplug core state synchronization
parisc: Switch to hotplug core state synchronization
...

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Merge drm/drm-next into drm-misc-next-fixes

Backmerging to sync drm-misc-next-fixes with drm-misc-next.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge branch 'drm-next' of git://anongit.freedesktop.org/drm/drm into msm-next-lumag-base

Merge the drm-next tree to pick up the DRM DSC helpers (merged via
drm-intel-next tree). MSM DSC v1.2 patche

Merge branch 'drm-next' of git://anongit.freedesktop.org/drm/drm into msm-next-lumag-base

Merge the drm-next tree to pick up the DRM DSC helpers (merged via
drm-intel-next tree). MSM DSC v1.2 patches depend on these helpers.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

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x86/mm: Allow guest.enc_status_change_prepare() to fail

TDX code is going to provide guest.enc_status_change_prepare() that is
able to fail. TDX will use the call to convert the GPA range from share

x86/mm: Allow guest.enc_status_change_prepare() to fail

TDX code is going to provide guest.enc_status_change_prepare() that is
able to fail. TDX will use the call to convert the GPA range from shared
to private. This operation can fail.

Add a way to return an error from the callback.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Link: https://lore.kernel.org/all/20230606095622.1939-2-kirill.shutemov%40linux.intel.com

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Merge tag 'v6.4-rc4' into wpan-next/staging

Linux 6.4-rc4

Merge drm/drm-next into drm-intel-gt-next

For conflict avoidance we need the following commit:

c9a9f18d3ad8 drm/i915/huc: use const struct bus_type pointers

Signed-off-by: Tvrtko Ursulin <tvrtko

Merge drm/drm-next into drm-intel-gt-next

For conflict avoidance we need the following commit:

c9a9f18d3ad8 drm/i915/huc: use const struct bus_type pointers

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

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x86/smpboot: Fix the parallel bringup decision

The decision to allow parallel bringup of secondary CPUs checks
CC_ATTR_GUEST_STATE_ENCRYPT to detect encrypted guests. Those cannot use
parallel bootu

x86/smpboot: Fix the parallel bringup decision

The decision to allow parallel bringup of secondary CPUs checks
CC_ATTR_GUEST_STATE_ENCRYPT to detect encrypted guests. Those cannot use
parallel bootup because accessing the local APIC is intercepted and raises
a #VC or #VE, which cannot be handled at that point.

The check works correctly, but only for AMD encrypted guests. TDX does not
set that flag.

As there is no real connection between CC attributes and the inability to
support parallel bringup, replace this with a generic control flag in
x86_cpuinit and let SEV-ES and TDX init code disable it.

Fixes: 0c7ffa32dbd6 ("x86/smpboot/64: Implement arch_cpuhp_init_parallel_bringup() and enable it")
Reported-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: https://lore.kernel.org/r/87ilc9gd2d.ffs@tglx

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Merge drm/drm-next into drm-intel-next

Backmerge to get some hwmon dependencies.

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

Merge drm/drm-fixes into drm-misc-fixes

Let's bring 6.4-rc1 in drm-misc-fixes to start the new fix cycle.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>