Commit Graph

3300 Commits

Author SHA1 Message Date
Alexandru Elisei
85592114ff KVM: arm64: VHE: Compute fgt traps before activating them
On VHE, the Fine Grain Traps registers are written to hardware in
kvm_arch_vcpu_load()->..->__activate_traps_hfgxtr(), but the fgt array is
computed later, in kvm_vcpu_load_fgt(). This can lead to zero being written
to the FGT registers the first time a VCPU is loaded. Also, any changes to
the fgt array will be visible only after the VCPU is scheduled out, and
then back in, which is not the intended behaviour.

Fix it by computing the fgt array just before the fgt traps are written
to hardware.

Fixes: fb10ddf35c ("KVM: arm64: Compute per-vCPU FGTs at vcpu_load()")
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reviewed-by: Oliver Upton <oupton@kernel.org>
Link: https://patch.msgid.link/20251112102853.47759-1-alexandru.elisei@arm.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-11-12 10:52:58 +00:00
Marc Zyngier
0f559cd91e KVM: arm64: Finalize ID registers only once per VM
Owing to the ID registers being global to the VM, there is no point
in computing them more than once.  However, recent changes making
use of kvm_set_vm_id_reg() outlined that we repeatedly hammer
the ID registers when we shouldn't.

Gate the ID reg update on the VM having never run.

Fixes: 50e7cce81b ("KVM: arm64: Limit clearing of ID_{AA64PFR0,PFR1}_EL1.GIC to userspace irqchip")
Fixes: 5cb57a1aff ("KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is presented to the guest")
Closes: https://lore.kernel.org/r/aRHf6x5umkTYhYJ3@finisterre.sirena.org.uk
Reported-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://patch.msgid.link/20251110173010.1918424-1-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-11-11 12:24:22 +00:00
Oliver Upton
66768669f2 KVM: arm64: vgic-v3: Release reserved slot outside of lpi_xa's lock
xa_release() expects to be called outside of the xa_lock. Fix
vgic_add_lpi() to drop the lock before calling and restructure to get
rid of the goto label.

Reported-by: Zenghui Yu <yuzenghui@huawei.com>
Closes: https://lore.kernel.org/kvmarm/d0853e82-7d95-5025-7abf-c6f1e0cdf7b5@huawei.com/
Fixes: 481c9ee846 ("KVM: arm64: vgic-its: Get rid of the lpi_list_lock")
Signed-off-by: Oliver Upton <oupton@kernel.org>
Link: https://patch.msgid.link/20251107184847.1784820-3-oupton@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-11-08 11:19:32 +00:00
Oliver Upton
75360a9a33 KVM: arm64: vgic-v3: Reinstate IRQ lock ordering for LPI xarray
Zenghui reports that running a KVM guest with an assigned device and
lockdep enabled produces an unfriendly splat due to an inconsistent irq
context when taking the lpi_xa's spinlock.

This is no good as in rare cases the last reference to an LPI can get
dropped after injection of a cached LPI translation. In this case,
vgic_put_irq() will release the IRQ struct and take the lpi_xa's
spinlock to erase it from the xarray.

Reinstate the IRQ ordering and update the lockdep hint accordingly. Note
that there is no irqsave equivalent of might_lock(), so just explictly
grab and release the spinlock on lockdep kernels.

Reported-by: Zenghui Yu <yuzenghui@huawei.com>
Closes: https://lore.kernel.org/kvmarm/b4d7cb0f-f007-0b81-46d1-998b15cc14bc@huawei.com/
Fixes: 982f31bbb5 ("KVM: arm64: vgic-v3: Don't require IRQs be disabled for LPI xarray lock")
Signed-off-by: Oliver Upton <oupton@kernel.org>
Link: https://patch.msgid.link/20251107184847.1784820-2-oupton@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-11-08 11:19:32 +00:00
Marc Zyngier
50e7cce81b KVM: arm64: Limit clearing of ID_{AA64PFR0,PFR1}_EL1.GIC to userspace irqchip
Now that the idreg's GIC field is in sync with the irqchip, limit
the runtime clearing of these fields to the pathological case where
we do not have an in-kernel GIC.

While we're at it, use the existing API instead of open-coded
accessors to access the ID regs.

Fixes: 5cb57a1aff ("KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is presented to the guest")
Reviewed-by: Oliver Upton <oupton@kernel.org>
Link: https://patch.msgid.link/20251030122707.2033690-4-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-11-08 11:17:28 +00:00
Marc Zyngier
8a9866ff86 KVM: arm64: Set ID_{AA64PFR0,PFR1}_EL1.GIC when GICv3 is configured
Drive the idreg fields indicating the presence of GICv3 directly from
the vgic code. This avoids having to do any sort of runtime clearing
of the idreg.

Fixes: 5cb57a1aff ("KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is presented to the guest")
Reviewed-by: Oliver Upton <oupton@kernel.org>
Link: https://patch.msgid.link/20251030122707.2033690-3-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-11-08 11:17:28 +00:00
Marc Zyngier
3f9eacf4f0 KVM: arm64: Make all 32bit ID registers fully writable
32bit ID registers aren't getting much love these days, and are
often missed in updates. One of these updates broke restoring
a GICv2 guest on a GICv3 machine.

Instead of performing a piecemeal fix, just bite the bullet
and make all 32bit ID regs fully writable. KVM itself never
relies on them for anything, and if the VMM wants to mess up
the guest, so be it.

Fixes: 5cb57a1aff ("KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is presented to the guest")
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Cc: stable@vger.kernel.org
Reviewed-by: Oliver Upton <oupton@kernel.org>
Link: https://patch.msgid.link/20251030122707.2033690-2-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-11-08 11:17:28 +00:00
Sebastian Ene
103e17aac0 KVM: arm64: Check the untrusted offset in FF-A memory share
Verify the offset to prevent OOB access in the hypervisor
FF-A buffer in case an untrusted large enough value
[U32_MAX - sizeof(struct ffa_composite_mem_region) + 1, U32_MAX]
is set from the host kernel.

Signed-off-by: Sebastian Ene <sebastianene@google.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://patch.msgid.link/20251017075710.2605118-1-sebastianene@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-30 16:14:58 +00:00
Vincent Donnefort
f71f7afd0a KVM: arm64: Check range args for pKVM mem transitions
There's currently no verification for host issued ranges in most of the
pKVM memory transitions. The end boundary might therefore be subject to
overflow and later checks could be evaded.

Close this loophole with an additional pfn_range_is_valid() check on a
per public function basis. Once this check has passed, it is safe to
convert pfn and nr_pages into a phys_addr_t and a size.

host_unshare_guest transition is already protected via
__check_host_shared_guest(), while assert_host_shared_guest() callers
are already ignoring host checks.

Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Link: https://patch.msgid.link/20251016164541.3771235-1-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-30 16:14:37 +00:00
Sascha Bischoff
da888524c3 KVM: arm64: vgic-v3: Trap all if no in-kernel irqchip
If there is no in-kernel irqchip for a GICv3 host set all of the trap
bits to block all accesses. This fixes the no-vgic-v3 selftest again.

Fixes: 3193287ddf ("KVM: arm64: gic-v3: Only set ICH_HCR traps for v2-on-v3 or v3 guests")
Reported-by: Mark Brown <broonie@kernel.org>
Closes: https://lore.kernel.org/all/23072856-6b8c-41e2-93d1-ea8a240a7079@sirena.org.uk
Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-by: Sebastian Ott <sebott@redhat.com>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://patch.msgid.link/20251021094358.1963807-1-sascha.bischoff@arm.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-30 16:11:21 +00:00
Oliver Upton
e0b5a7967d KVM: arm64: nv: Use FGT write trap of MDSCR_EL1 when available
Marc reports that the performance of running an L3 guest has regressed
by 60% as a result of setting MDCR_EL2.TDA to hide bad architecture.
That's of course terrible for the single user of recursive NV ;-)

While there's nothing to be done on non-FGT systems, take advantage of
the precise write trap of MDSCR_EL1 and leave the rest of the debug
registers untrapped.

Reported-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:44:37 +01:00
Oliver Upton
fb10ddf35c KVM: arm64: Compute per-vCPU FGTs at vcpu_load()
To date KVM has used the fine-grained traps for the sake of UNDEF
enforcement (so-called FGUs), meaning the constituent parts could be
computed on a per-VM basis and folded into the effective value when
programmed.

Prepare for traps changing based on the vCPU context by computing the
whole mess of them at vcpu_load(). Aggressively inline all the helpers
to preserve the build-time checks that were there before.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:44:37 +01:00
Marc Zyngier
386aac77da KVM: arm64: Kill leftovers of ad-hoc timer userspace access
Now that the whole timer infrastructure is handled as system register
accesses, get rid of the now unused ad-hoc infrastructure.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:42:41 +01:00
Marc Zyngier
892f7c38ba KVM: arm64: Fix WFxT handling of nested virt
The spec for WFxT indicates that the parameter to the WFxT instruction
is relative to the reading of CNTVCT_EL0. This means that the implementation
needs to take the execution context into account, as CNTVOFF_EL2
does not always affect readings of CNTVCT_EL0 (such as when HCR_EL2.E2H
is 1 and that we're in host context).

This also rids us of the last instance of KVM_REG_ARM_TIMER_CNT
outside of the userspace interaction code.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:42:41 +01:00
Marc Zyngier
c3be3a48fb KVM: arm64: Move CNT*CT_EL0 userspace accessors to generic infrastructure
Moving the counter registers is a bit more involved than for the control
and comparator (there is no shadow data for the counter), but still
pretty manageable.

Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:42:41 +01:00
Marc Zyngier
8af198980e KVM: arm64: Move CNT*_CVAL_EL0 userspace accessors to generic infrastructure
As for the control registers, move the comparator registers to
the common infrastructure.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:42:41 +01:00
Marc Zyngier
09424d5d7d KVM: arm64: Move CNT*_CTL_EL0 userspace accessors to generic infrastructure
Remove the handling of CNT*_CTL_EL0 from guest.c, and move it to
sys_regs.c, using a new TIMER_REG() definition to encapsulate it.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:42:40 +01:00
Marc Zyngier
77a0c42eaf KVM: arm64: Add timer UAPI workaround to sysreg infrastructure
Amongst the numerous bugs that plague the KVM/arm64 UAPI, one of
the most annoying thing is that the userspace view of the virtual
timer has its CVAL and CNT encodings swapped.

In order to reduce the amount of code that has to know about this,
start by adding handling for this bug in the sys_reg code.

Nothing is making use of it yet, as the code responsible for userspace
interaction is catching the accesses early.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:42:40 +01:00
Marc Zyngier
a92d552266 KVM: arm64: Make timer_set_offset() generally accessible
Move the timer_set_offset() helper to arm_arch_timer.h, so that it
is next to timer_get_offset(), and accessible by the rest of KVM.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:42:40 +01:00
Marc Zyngier
8625a670af KVM: arm64: Replace timer context vcpu pointer with timer_id
Having to follow a pointer to a vcpu is pretty dumb, when the timers
are are a fixed offset in the vcpu structure itself.

Trade the vcpu pointer for a timer_id, which can then be used to
compute the vcpu address as needed.

Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:42:40 +01:00
Marc Zyngier
aa68975c97 KVM: arm64: Introduce timer_context_to_vcpu() helper
We currently have a vcpu pointer nested into each timer context.

As we are about to remove this pointer, introduce a helper (aptly
named timer_context_to_vcpu()) that returns this pointer, at least
until we repaint the data structure.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:42:40 +01:00
Marc Zyngier
4cab5c857d KVM: arm64: Hide CNTHV_*_EL2 from userspace for nVHE guests
Although we correctly UNDEF any CNTHV_*_EL2 access from the guest
when E2H==0, we still expose these registers to userspace, which
is a bad idea.

Drop the ad-hoc UNDEF injection and switch to a .visibility()
callback which will also hide the register from userspace.

Fixes: 0e45981028 ("KVM: arm64: timer: Don't adjust the EL2 virtual timer offset")
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:42:40 +01:00
Sascha Bischoff
3193287ddf KVM: arm64: gic-v3: Only set ICH_HCR traps for v2-on-v3 or v3 guests
The ICH_HCR_EL2 traps are used when running on GICv3 hardware, or when
running a GICv3-based guest using FEAT_GCIE_LEGACY on GICv5
hardware. When running a GICv2 guest on GICv3 hardware the traps are
used to ensure that the guest never sees any part of GICv3 (only GICv2
is visible to the guest), and when running a GICv3 guest they are used
to trap in specific scenarios. They are not applicable for a
GICv2-native guest, and won't be applicable for a(n upcoming) GICv5
guest.

The traps themselves are configured in the vGIC CPU IF state, which is
stored as a union. Updating the wrong aperture of the union risks
corrupting state, and therefore needs to be avoided at all costs.

Bail early if we're not running a compatible guest (GICv2 on GICv3
hardware, GICv3 native, GICv3 on GICv5 hardware). Trap everything
unconditionally if we're running a GICv2 guest on GICv3
hardware. Otherwise, conditionally set up GICv3-native trapping.

Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:40:33 +01:00
Mukesh Ojha
c35dd83866 KVM: arm64: Guard PMSCR_EL1 initialization with SPE presence check
Commit efad60e460 ("KVM: arm64: Initialize PMSCR_EL1 when in VHE")
does not perform sufficient check before initializing PMSCR_EL1 to 0
when running in VHE mode. On some platforms, this causes the system to
hang during boot, as EL3 has not delegated access to the Profiling
Buffer to the Non-secure world, nor does it reinject an UNDEF on sysreg
trap.

To avoid this issue, restrict the PMSCR_EL1 initialization to CPUs that
support Statistical Profiling Extension (FEAT_SPE) and have the
Profiling Buffer accessible in Non-secure EL1. This is determined via a
new helper `cpu_has_spe()` which checks both PMSVer and PMBIDR_EL1.P.

This ensures the initialization only affects CPUs where SPE is
implemented and usable, preventing boot failures on platforms where SPE
is not properly configured.

Fixes: efad60e460 ("KVM: arm64: Initialize PMSCR_EL1 when in VHE")
Signed-off-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:26:36 +01:00
Osama Abdelkader
05a02490fa KVM: arm64: Remove unreachable break after return
Remove an unnecessary 'break' statement that follows a 'return'
in arch/arm64/kvm/at.c. The break is unreachable.

Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:17:03 +01:00
Oliver Upton
0aa1b76fe1 KVM: arm64: Prevent access to vCPU events before init
Another day, another syzkaller bug. KVM erroneously allows userspace to
pend vCPU events for a vCPU that hasn't been initialized yet, leading to
KVM interpreting a bunch of uninitialized garbage for routing /
injecting the exception.

In one case the injection code and the hyp disagree on whether the vCPU
has a 32bit EL1 and put the vCPU into an illegal mode for AArch64,
tripping the BUG() in exception_target_el() during the next injection:

  kernel BUG at arch/arm64/kvm/inject_fault.c:40!
  Internal error: Oops - BUG: 00000000f2000800 [#1]  SMP
  CPU: 3 UID: 0 PID: 318 Comm: repro Not tainted 6.17.0-rc4-00104-g10fd0285305d #6 PREEMPT
  Hardware name: linux,dummy-virt (DT)
  pstate: 21402009 (nzCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
  pc : exception_target_el+0x88/0x8c
  lr : pend_serror_exception+0x18/0x13c
  sp : ffff800082f03a10
  x29: ffff800082f03a10 x28: ffff0000cb132280 x27: 0000000000000000
  x26: 0000000000000000 x25: ffff0000c2a99c20 x24: 0000000000000000
  x23: 0000000000008000 x22: 0000000000000002 x21: 0000000000000004
  x20: 0000000000008000 x19: ffff0000c2a99c20 x18: 0000000000000000
  x17: 0000000000000000 x16: 0000000000000000 x15: 00000000200000c0
  x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
  x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
  x8 : ffff800082f03af8 x7 : 0000000000000000 x6 : 0000000000000000
  x5 : ffff800080f621f0 x4 : 0000000000000000 x3 : 0000000000000000
  x2 : 000000000040009b x1 : 0000000000000003 x0 : ffff0000c2a99c20
  Call trace:
   exception_target_el+0x88/0x8c (P)
   kvm_inject_serror_esr+0x40/0x3b4
   __kvm_arm_vcpu_set_events+0xf0/0x100
   kvm_arch_vcpu_ioctl+0x180/0x9d4
   kvm_vcpu_ioctl+0x60c/0x9f4
   __arm64_sys_ioctl+0xac/0x104
   invoke_syscall+0x48/0x110
   el0_svc_common.constprop.0+0x40/0xe0
   do_el0_svc+0x1c/0x28
   el0_svc+0x34/0xf0
   el0t_64_sync_handler+0xa0/0xe4
   el0t_64_sync+0x198/0x19c
  Code: f946bc01 b4fffe61 9101e020 17fffff2 (d4210000)

Reject the ioctls outright as no sane VMM would call these before
KVM_ARM_VCPU_INIT anyway. Even if it did the exception would've been
thrown away by the eventual reset of the vCPU's state.

Cc: stable@vger.kernel.org # 6.17
Fixes: b7b27facc7 ("arm/arm64: KVM: Add KVM_GET/SET_VCPU_EVENTS")
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:17:03 +01:00
Oliver Upton
a46c09b382 KVM: arm64: Use the in-context stage-1 in __kvm_find_s1_desc_level()
Running the external_aborts selftest at EL2 leads to an ugly splat due
to the stage-1 MMU being disabled for the walked context, owing to the
fact that __kvm_find_s1_desc_level() is hardcoded to the EL1&0 regime.

Select the appropriate translation regime for the stage-1 walk based on
the current vCPU context.

Fixes: b8e625167a ("KVM: arm64: Add S1 IPA to page table level walker")
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:17:03 +01:00
Marc Zyngier
9a1950f977 KVM: arm64: nv: Don't advance PC when pending an SVE exception
Jan reports that running a nested guest on Neoverse-V2 leads to a WARN
in the host due to simultaneously pending an exception and PC increment
after an access to ZCR_EL2.

Returning true from a sysreg accessor is an indication that the sysreg
instruction has been retired. Of course this isn't the case when we've
pended a synchronous SVE exception for the guest. Fix the return value
and let the exception propagate to the guest as usual.

Reported-by: Jan Kotas <jank@cadence.com>
Closes: https://lore.kernel.org/kvmarm/865xd61tt5.wl-maz@kernel.org/
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:17:03 +01:00
Oliver Upton
ed25dcfbc4 KVM: arm64: nv: Don't treat ZCR_EL2 as a 'mapped' register
Unlike the other mapped EL2 sysregs ZCR_EL2 isn't guaranteed to be
resident when a vCPU is loaded as it actually follows the SVE
context. As such, the contents of ZCR_EL1 may belong to another guest if
the vCPU has been preempted before reaching sysreg emulation.

Unconditionally use the in-memory value of ZCR_EL2 and switch to the
memory-only accessors. The in-memory value is guaranteed to be valid as
fpsimd_lazy_switch_to_{guest,host}() will restore/save the register
appropriately.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-10-13 14:17:02 +01:00
Linus Torvalds
2215336295 hyperv-next for v6.18
-----BEGIN PGP SIGNATURE-----
 
 iQFHBAABCgAxFiEEIbPD0id6easf0xsudhRwX5BBoF4FAmjkpakTHHdlaS5saXVA
 a2VybmVsLm9yZwAKCRB2FHBfkEGgXip5B/48MvTFJ1qwRGPVzevZQ8Z4SDogEREp
 69VS/xRf1YCIzyXyanwqf1dXLq8NAqicSp6ewpJAmNA55/9O0cwT2EtohjeGCu61
 krPIvS3KT7xI0uSEniBdhBtALYBscnQ0e3cAbLNzL7bwA6Q6OmvoIawpBADgE/cW
 aZNCK9jy+WUqtXc6lNtkJtST0HWGDn0h04o2hjqIkZ+7ewjuEEJBUUB/JZwJ41Od
 UxbID0PAcn9O4n/u/Y/GH65MX+ddrdCgPHEGCLAGAKT24lou3NzVv445OuCw0c4W
 ilALIRb9iea56ZLVBW5O82+7g9Ag41LGq+841MNlZjeRNONGykaUpTWZ
 =OR26
 -----END PGP SIGNATURE-----

Merge tag 'hyperv-next-signed-20251006' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

Pull hyperv updates from Wei Liu:

 - Unify guest entry code for KVM and MSHV (Sean Christopherson)

 - Switch Hyper-V MSI domain to use msi_create_parent_irq_domain()
   (Nam Cao)

 - Add CONFIG_HYPERV_VMBUS and limit the semantics of CONFIG_HYPERV
   (Mukesh Rathor)

 - Add kexec/kdump support on Azure CVMs (Vitaly Kuznetsov)

 - Deprecate hyperv_fb in favor of Hyper-V DRM driver (Prasanna
   Kumar T S M)

 - Miscellaneous enhancements, fixes and cleanups (Abhishek Tiwari,
   Alok Tiwari, Nuno Das Neves, Wei Liu, Roman Kisel, Michael Kelley)

* tag 'hyperv-next-signed-20251006' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  hyperv: Remove the spurious null directive line
  MAINTAINERS: Mark hyperv_fb driver Obsolete
  fbdev/hyperv_fb: deprecate this in favor of Hyper-V DRM driver
  Drivers: hv: Make CONFIG_HYPERV bool
  Drivers: hv: Add CONFIG_HYPERV_VMBUS option
  Drivers: hv: vmbus: Fix typos in vmbus_drv.c
  Drivers: hv: vmbus: Fix sysfs output format for ring buffer index
  Drivers: hv: vmbus: Clean up sscanf format specifier in target_cpu_store()
  x86/hyperv: Switch to msi_create_parent_irq_domain()
  mshv: Use common "entry virt" APIs to do work in root before running guest
  entry: Rename "kvm" entry code assets to "virt" to genericize APIs
  entry/kvm: KVM: Move KVM details related to signal/-EINTR into KVM proper
  mshv: Handle NEED_RESCHED_LAZY before transferring to guest
  x86/hyperv: Add kexec/kdump support on Azure CVMs
  Drivers: hv: Simplify data structures for VMBus channel close message
  Drivers: hv: util: Cosmetic changes for hv_utils_transport.c
  mshv: Add support for a new parent partition configuration
  clocksource: hyper-v: Skip unnecessary checks for the root partition
  hyperv: Add missing field to hv_output_map_device_interrupt
2025-10-07 08:40:15 -07:00
Linus Torvalds
f3826aa996 guest_memfd:
* Add support for host userspace mapping of guest_memfd-backed memory for VM
   types that do NOT use support KVM_MEMORY_ATTRIBUTE_PRIVATE (which isn't
   precisely the same thing as CoCo VMs, since x86's SEV-MEM and SEV-ES have
   no way to detect private vs. shared).
 
   This lays the groundwork for removal of guest memory from the kernel direct
   map, as well as for limited mmap() for guest_memfd-backed memory.
 
   For more information see:
   * a6ad54137a ("Merge branch 'guest-memfd-mmap' into HEAD", 2025-08-27)
   * https://github.com/firecracker-microvm/firecracker/tree/feature/secret-hiding
     (guest_memfd in Firecracker)
   * https://lore.kernel.org/all/20250221160728.1584559-1-roypat@amazon.co.uk/
     (direct map removal)
   * https://lore.kernel.org/all/20250328153133.3504118-1-tabba@google.com/
     (mmap support)
 
 ARM:
 
 * Add support for FF-A 1.2 as the secure memory conduit for pKVM,
   allowing more registers to be used as part of the message payload.
 
 * Change the way pKVM allocates its VM handles, making sure that the
   privileged hypervisor is never tricked into using uninitialised
   data.
 
 * Speed up MMIO range registration by avoiding unnecessary RCU
   synchronisation, which results in VMs starting much quicker.
 
 * Add the dump of the instruction stream when panic-ing in the EL2
   payload, just like the rest of the kernel has always done. This will
   hopefully help debugging non-VHE setups.
 
 * Add 52bit PA support to the stage-1 page-table walker, and make use
   of it to populate the fault level reported to the guest on failing
   to translate a stage-1 walk.
 
 * Add NV support to the GICv3-on-GICv5 emulation code, ensuring
   feature parity for guests, irrespective of the host platform.
 
 * Fix some really ugly architecture problems when dealing with debug
   in a nested VM. This has some bad performance impacts, but is at
   least correct.
 
 * Add enough infrastructure to be able to disable EL2 features and
   give effective values to the EL2 control registers. This then allows
   a bunch of features to be turned off, which helps cross-host
   migration.
 
 * Large rework of the selftest infrastructure to allow most tests to
   transparently run at EL2. This is the first step towards enabling
   NV testing.
 
 * Various fixes and improvements all over the map, including one BE
   fix, just in time for the removal of the feature.
 
 LoongArch:
 
 * Detect page table walk feature on new hardware
 
 * Add sign extension with kernel MMIO/IOCSR emulation
 
 * Improve in-kernel IPI emulation
 
 * Improve in-kernel PCH-PIC emulation
 
 * Move kvm_iocsr tracepoint out of generic code
 
 RISC-V:
 
 * Added SBI FWFT extension for Guest/VM with misaligned delegation and
   pointer masking PMLEN features
 
 * Added ONE_REG interface for SBI FWFT extension
 
 * Added Zicbop and bfloat16 extensions for Guest/VM
 
 * Enabled more common KVM selftests for RISC-V
 
 * Added SBI v3.0 PMU enhancements in KVM and perf driver
 
 s390:
 
 * Improve interrupt cpu for wakeup, in particular the heuristic to decide
   which vCPU to deliver a floating interrupt to.
 
 * Clear the PTE when discarding a swapped page because of CMMA; this
   bug was introduced in 6.16 when refactoring gmap code.
 
 x86 selftests:
 
 * Add #DE coverage in the fastops test (the only exception that's guest-
   triggerable in fastop-emulated instructions).
 
 * Fix PMU selftests errors encountered on Granite Rapids (GNR), Sierra
   Forest (SRF) and Clearwater Forest (CWF).
 
 * Minor cleanups and improvements
 
 x86 (guest side):
 
 * For the legacy PCI hole (memory between TOLUD and 4GiB) to UC when
   overriding guest MTRR for TDX/SNP to fix an issue where ACPI auto-mapping
   could map devices as WB and prevent the device drivers from mapping their
   devices with UC/UC-.
 
 * Make kvm_async_pf_task_wake() a local static helper and remove its
   export.
 
 * Use native qspinlocks when running in a VM with dedicated vCPU=>pCPU
   bindings even when PV_UNHALT is unsupported.
 
 Generic:
 
 * Remove a redundant __GFP_NOWARN from kvm_setup_async_pf() as __GFP_NOWARN is
   now included in GFP_NOWAIT.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmjcGSkUHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroPSPAgAnJDswU4fZ5YdJr6jGzsbSQ6utlIV
 FeEltLKQIM7Aq/uvL6PLN5Kx1Pb/d9r9ag39mDT6lq9fOfJdOLjJr2SBXPTCsrPS
 6hyNL1mlgo5qzs54T8dkMbQThlSgA4zaehsc0zl8vnwil6ygoAdrtTHqZm6V0hu/
 F/sVlikCsLix1hC0KtzwscyWYcjWtXfVoi9eU5WY6ALpQaVXfRUtwyOhGDkldr+m
 i3iDiGiLAZ5Iu3igUCIOEzSSQY0FgLJpzbwJAeUxIvomDkHGJLaR14ijvM+NkRZi
 FBo2CLbjrwXb56Rbh2ABcq0CGJ3EiU3L+CC34UaRLzbtl/2BtpetkC3irA==
 =fyov
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "This excludes the bulk of the x86 changes, which I will send
  separately. They have two not complex but relatively unusual conflicts
  so I will wait for other dust to settle.

  guest_memfd:

   - Add support for host userspace mapping of guest_memfd-backed memory
     for VM types that do NOT use support KVM_MEMORY_ATTRIBUTE_PRIVATE
     (which isn't precisely the same thing as CoCo VMs, since x86's
     SEV-MEM and SEV-ES have no way to detect private vs. shared).

     This lays the groundwork for removal of guest memory from the
     kernel direct map, as well as for limited mmap() for
     guest_memfd-backed memory.

     For more information see:
       - commit a6ad54137a ("Merge branch 'guest-memfd-mmap' into HEAD")
       - guest_memfd in Firecracker:
           https://github.com/firecracker-microvm/firecracker/tree/feature/secret-hiding
       - direct map removal:
           https://lore.kernel.org/all/20250221160728.1584559-1-roypat@amazon.co.uk/
       - mmap support:
           https://lore.kernel.org/all/20250328153133.3504118-1-tabba@google.com/

  ARM:

   - Add support for FF-A 1.2 as the secure memory conduit for pKVM,
     allowing more registers to be used as part of the message payload.

   - Change the way pKVM allocates its VM handles, making sure that the
     privileged hypervisor is never tricked into using uninitialised
     data.

   - Speed up MMIO range registration by avoiding unnecessary RCU
     synchronisation, which results in VMs starting much quicker.

   - Add the dump of the instruction stream when panic-ing in the EL2
     payload, just like the rest of the kernel has always done. This
     will hopefully help debugging non-VHE setups.

   - Add 52bit PA support to the stage-1 page-table walker, and make use
     of it to populate the fault level reported to the guest on failing
     to translate a stage-1 walk.

   - Add NV support to the GICv3-on-GICv5 emulation code, ensuring
     feature parity for guests, irrespective of the host platform.

   - Fix some really ugly architecture problems when dealing with debug
     in a nested VM. This has some bad performance impacts, but is at
     least correct.

   - Add enough infrastructure to be able to disable EL2 features and
     give effective values to the EL2 control registers. This then
     allows a bunch of features to be turned off, which helps cross-host
     migration.

   - Large rework of the selftest infrastructure to allow most tests to
     transparently run at EL2. This is the first step towards enabling
     NV testing.

   - Various fixes and improvements all over the map, including one BE
     fix, just in time for the removal of the feature.

  LoongArch:

   - Detect page table walk feature on new hardware

   - Add sign extension with kernel MMIO/IOCSR emulation

   - Improve in-kernel IPI emulation

   - Improve in-kernel PCH-PIC emulation

   - Move kvm_iocsr tracepoint out of generic code

  RISC-V:

   - Added SBI FWFT extension for Guest/VM with misaligned delegation
     and pointer masking PMLEN features

   - Added ONE_REG interface for SBI FWFT extension

   - Added Zicbop and bfloat16 extensions for Guest/VM

   - Enabled more common KVM selftests for RISC-V

   - Added SBI v3.0 PMU enhancements in KVM and perf driver

  s390:

   - Improve interrupt cpu for wakeup, in particular the heuristic to
     decide which vCPU to deliver a floating interrupt to.

   - Clear the PTE when discarding a swapped page because of CMMA; this
     bug was introduced in 6.16 when refactoring gmap code.

  x86 selftests:

   - Add #DE coverage in the fastops test (the only exception that's
     guest- triggerable in fastop-emulated instructions).

   - Fix PMU selftests errors encountered on Granite Rapids (GNR),
     Sierra Forest (SRF) and Clearwater Forest (CWF).

   - Minor cleanups and improvements

  x86 (guest side):

   - For the legacy PCI hole (memory between TOLUD and 4GiB) to UC when
     overriding guest MTRR for TDX/SNP to fix an issue where ACPI
     auto-mapping could map devices as WB and prevent the device drivers
     from mapping their devices with UC/UC-.

   - Make kvm_async_pf_task_wake() a local static helper and remove its
     export.

   - Use native qspinlocks when running in a VM with dedicated
     vCPU=>pCPU bindings even when PV_UNHALT is unsupported.

  Generic:

   - Remove a redundant __GFP_NOWARN from kvm_setup_async_pf() as
     __GFP_NOWARN is now included in GFP_NOWAIT.

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (178 commits)
  KVM: s390: Fix to clear PTE when discarding a swapped page
  KVM: arm64: selftests: Cover ID_AA64ISAR3_EL1 in set_id_regs
  KVM: arm64: selftests: Remove a duplicate register listing in set_id_regs
  KVM: arm64: selftests: Cope with arch silliness in EL2 selftest
  KVM: arm64: selftests: Add basic test for running in VHE EL2
  KVM: arm64: selftests: Enable EL2 by default
  KVM: arm64: selftests: Initialize HCR_EL2
  KVM: arm64: selftests: Use the vCPU attr for setting nr of PMU counters
  KVM: arm64: selftests: Use hyp timer IRQs when test runs at EL2
  KVM: arm64: selftests: Select SMCCC conduit based on current EL
  KVM: arm64: selftests: Provide helper for getting default vCPU target
  KVM: arm64: selftests: Alias EL1 registers to EL2 counterparts
  KVM: arm64: selftests: Create a VGICv3 for 'default' VMs
  KVM: arm64: selftests: Add unsanitised helpers for VGICv3 creation
  KVM: arm64: selftests: Add helper to check for VGICv3 support
  KVM: arm64: selftests: Initialize VGICv3 only once
  KVM: arm64: selftests: Provide kvm_arch_vm_post_create() in library code
  KVM: selftests: Add ex_str() to print human friendly name of exception vectors
  selftests/kvm: remove stale TODO in xapic_state_test
  KVM: selftests: Handle Intel Atom errata that leads to PMU event overcount
  ...
2025-10-04 08:52:16 -07:00
Sean Christopherson
9be7e1e320 entry: Rename "kvm" entry code assets to "virt" to genericize APIs
Rename the "kvm" entry code files and Kconfigs to use generic "virt"
nomenclature so that the code can be reused by other hypervisors (or
rather, their root/dom0 partition drivers), without incorrectly suggesting
the code somehow relies on and/or involves KVM.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
2025-09-30 22:50:18 +00:00
Sean Christopherson
6d0386ea99 entry/kvm: KVM: Move KVM details related to signal/-EINTR into KVM proper
Move KVM's morphing of pending signals into userspace exits into KVM
proper, and drop the @vcpu param from xfer_to_guest_mode_handle_work().
How KVM responds to -EINTR is a detail that really belongs in KVM itself,
and invoking kvm_handle_signal_exit() from kernel code creates an inverted
module dependency.  E.g. attempting to move kvm_handle_signal_exit() into
kvm_main.c would generate an linker error when building kvm.ko as a module.

Dropping KVM details will also converting the KVM "entry" code into a more
generic virtualization framework so that it can be used when running as a
Hyper-V root partition.

Lastly, eliminating usage of "struct kvm_vcpu" outside of KVM is also nice
to have for KVM x86 developers, as keeping the details of kvm_vcpu purely
within KVM allows changing the layout of the structure without having to
boot into a new kernel, e.g. allows rebuilding and reloading kvm.ko with a
modified kvm_vcpu structure as part of debug/development.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
2025-09-30 22:50:18 +00:00
Paolo Bonzini
924ebaefce KVM/arm64 updates for 6.18
- Add support for FF-A 1.2 as the secure memory conduit for pKVM,
   allowing more registers to be used as part of the message payload.
 
 - Change the way pKVM allocates its VM handles, making sure that the
   privileged hypervisor is never tricked into using uninitialised
   data.
 
 - Speed up MMIO range registration by avoiding unnecessary RCU
   synchronisation, which results in VMs starting much quicker.
 
 - Add the dump of the instruction stream when panic-ing in the EL2
   payload, just like the rest of the kernel has always done. This will
   hopefully help debugging non-VHE setups.
 
 - Add 52bit PA support to the stage-1 page-table walker, and make use
   of it to populate the fault level reported to the guest on failing
   to translate a stage-1 walk.
 
 - Add NV support to the GICv3-on-GICv5 emulation code, ensuring
   feature parity for guests, irrespective of the host platform.
 
 - Fix some really ugly architecture problems when dealing with debug
   in a nested VM. This has some bad performance impacts, but is at
   least correct.
 
 - Add enough infrastructure to be able to disable EL2 features and
   give effective values to the EL2 control registers. This then allows
   a bunch of features to be turned off, which helps cross-host
   migration.
 
 - Large rework of the selftest infrastructure to allow most tests to
   transparently run at EL2. This is the first step towards enabling
   NV testing.
 
 - Various fixes and improvements all over the map, including one BE
   fix, just in time for the removal of the feature.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAmjVhSsACgkQI9DQutE9
 ekOSIg//YdbA/zo17GrLnJnlGdUnS0e3/357n3e5Lypx1UFRDTmNacpVPw4VG/jt
 eVpQn7AgYwyvKfCq46eD+hBBqNv1XTn4DeXttv7CmVqhCRythsEvDkTBWSt7oYUZ
 xfYXCMKNhqUElH4AbYYx3y7nb2E9/KVGr+NBn6Vf5c14OZ3MGVc/fyp4jM1ih5dR
 kcV2onAYohlIGvFEyZMBtJ+jkYkqfIbfxfqCL0RAET0aEBFcmM1aXybWZj47hlLM
 f2j+E6cFQ0ZzUt+3pFhT75wo43lHGtIFDjVd60uishyU+NXTVvqRmXDTRU4k546W
 18HHX1yijbzuXIatVhVRo2hIq3jKU37T9wtj46BejbDHRdAPENEyN/Qopm7rNS+X
 mCwOT7He6KR+H4rU6nFaTcsS7bNRCvIbZP9i9zb6NElbvXu5QnM8BUQsYFCDUa/n
 xtbtQlckbo/7zeoUsBDrGj2XmCf0d45FTHb7fdWOYEmMSmJhXYpUKdM4JcLyhKoQ
 DD0ox2S+pt2lwNw3XOSABdES0KJxCvDASAMIgn2h2sGpY8FxsBcVW/BufXopdafG
 UeInxWaILp2iCDM4tH2GLjKqlvMAOwcA+mAEZToXypxlJAnYA6J1pXCF8WEaM6+D
 BGrLli8Zd8JRs87byq6K7tp8oLNzZdliJp73j5jfOHTJA4MnvFI=
 =iAL3
 -----END PGP SIGNATURE-----

Merge tag 'kvmarm-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 updates for 6.18

- Add support for FF-A 1.2 as the secure memory conduit for pKVM,
  allowing more registers to be used as part of the message payload.

- Change the way pKVM allocates its VM handles, making sure that the
  privileged hypervisor is never tricked into using uninitialised
  data.

- Speed up MMIO range registration by avoiding unnecessary RCU
  synchronisation, which results in VMs starting much quicker.

- Add the dump of the instruction stream when panic-ing in the EL2
  payload, just like the rest of the kernel has always done. This will
  hopefully help debugging non-VHE setups.

- Add 52bit PA support to the stage-1 page-table walker, and make use
  of it to populate the fault level reported to the guest on failing
  to translate a stage-1 walk.

- Add NV support to the GICv3-on-GICv5 emulation code, ensuring
  feature parity for guests, irrespective of the host platform.

- Fix some really ugly architecture problems when dealing with debug
  in a nested VM. This has some bad performance impacts, but is at
  least correct.

- Add enough infrastructure to be able to disable EL2 features and
  give effective values to the EL2 control registers. This then allows
  a bunch of features to be turned off, which helps cross-host
  migration.

- Large rework of the selftest infrastructure to allow most tests to
  transparently run at EL2. This is the first step towards enabling
  NV testing.

- Various fixes and improvements all over the map, including one BE
  fix, just in time for the removal of the feature.
2025-09-30 13:23:28 -04:00
Paolo Bonzini
8cbb0df294 KVM/arm64 changes for 6.17, round #3
- Invalidate nested MMUs upon freeing the PGD to avoid WARNs when
    visiting from an MMU notifier
 
  - Fixes to the TLB match process and TLB invalidation range for
    managing the VCNR pseudo-TLB
 
  - Prevent SPE from erroneously profiling guests due to UNKNOWN reset
    values in PMSCR_EL1
 
  - Fix save/restore of host MDCR_EL2 to account for eagerly programming
    at vcpu_load() on VHE systems
 
  - Correct lock ordering when dealing with VGIC LPIs, avoiding scenarios
    where an xarray's spinlock was nested with a *raw* spinlock
 
  - Permit stage-2 read permission aborts which are possible in the case
    of NV depending on the guest hypervisor's stage-2 translation
 
  - Call raw_spin_unlock() instead of the internal spinlock API
 
  - Fix parameter ordering when assigning VBAR_EL1
 -----BEGIN PGP SIGNATURE-----
 
 iI0EABYIADUWIQSNXHjWXuzMZutrKNKivnWIJHzdFgUCaMHCvxccb2xpdmVyLnVw
 dG9uQGxpbnV4LmRldgAKCRCivnWIJHzdFqbCAP9ygpb3tkpAPkbaB68IwyJgGD/C
 59f2NTUGkzak20SjHAD+IcvQV8GemDsGNvSvjpb08KrNWMUxeuOBiAp/IvqrqwU=
 =VrcD
 -----END PGP SIGNATURE-----

Merge tag 'kvmarm-fixes-6.17-2' of https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 changes for 6.17, round #3

 - Invalidate nested MMUs upon freeing the PGD to avoid WARNs when
   visiting from an MMU notifier

 - Fixes to the TLB match process and TLB invalidation range for
   managing the VCNR pseudo-TLB

 - Prevent SPE from erroneously profiling guests due to UNKNOWN reset
   values in PMSCR_EL1

 - Fix save/restore of host MDCR_EL2 to account for eagerly programming
   at vcpu_load() on VHE systems

 - Correct lock ordering when dealing with VGIC LPIs, avoiding scenarios
   where an xarray's spinlock was nested with a *raw* spinlock

 - Permit stage-2 read permission aborts which are possible in the case
   of NV depending on the guest hypervisor's stage-2 translation

 - Call raw_spin_unlock() instead of the internal spinlock API

 - Fix parameter ordering when assigning VBAR_EL1

[Pull into kvm/master to fix conflicts. - Paolo]
2025-09-30 13:23:06 -04:00
Linus Torvalds
a5ba183bde hardening updates for v6.18-rc1
- Clean up usage of TRAILING_OVERLAP() (Gustavo A. R. Silva)
 
 - lkdtm: fortify: Fix potential NULL dereference on kmalloc failure
   (Junjie Cao)
 
 - Add str_assert_deassert() helper (Lad Prabhakar)
 
 - gcc-plugins: Remove TODO_verify_il for GCC >= 16
 
 - kconfig: Fix BrokenPipeError warnings in selftests
 
 - kconfig: Add transitional symbol attribute for migration support
 
 - kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRSPkdeREjth1dHnSE2KwveOeQkuwUCaNraNQAKCRA2KwveOeQk
 u/DkAPwKPP5BSmVR2wkdpQaXIr3PGA+cbBYp34DMJNujZ9piIwD/WZ+HfGTLoERy
 +2Q6HLj9hUdd+Rx3IZ8/w1QmnhUIUAU=
 =AwV9
 -----END PGP SIGNATURE-----

Merge tag 'hardening-v6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull hardening updates from Kees Cook:
 "One notable addition is the creation of the 'transitional' keyword for
  kconfig so CONFIG renaming can go more smoothly.

  This has been a long-standing deficiency, and with the renaming of
  CONFIG_CFI_CLANG to CONFIG_CFI (since GCC will soon have KCFI
  support), this came up again.

  The breadth of the diffstat is mainly this renaming.

   - Clean up usage of TRAILING_OVERLAP() (Gustavo A. R. Silva)

   - lkdtm: fortify: Fix potential NULL dereference on kmalloc failure
     (Junjie Cao)

   - Add str_assert_deassert() helper (Lad Prabhakar)

   - gcc-plugins: Remove TODO_verify_il for GCC >= 16

   - kconfig: Fix BrokenPipeError warnings in selftests

   - kconfig: Add transitional symbol attribute for migration support

   - kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI"

* tag 'hardening-v6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  lib/string_choices: Add str_assert_deassert() helper
  kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI
  kconfig: Add transitional symbol attribute for migration support
  kconfig: Fix BrokenPipeError warnings in selftests
  gcc-plugins: Remove TODO_verify_il for GCC >= 16
  stddef: Introduce __TRAILING_OVERLAP()
  stddef: Remove token-pasting in TRAILING_OVERLAP()
  lkdtm: fortify: Fix potential NULL dereference on kmalloc failure
2025-09-29 17:48:27 -07:00
Kees Cook
23ef9d4397 kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI
The kernel's CFI implementation uses the KCFI ABI specifically, and is
not strictly tied to a particular compiler. In preparation for GCC
supporting KCFI, rename CONFIG_CFI_CLANG to CONFIG_CFI (along with
associated options).

Use new "transitional" Kconfig option for old CONFIG_CFI_CLANG that will
enable CONFIG_CFI during olddefconfig.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250923213422.1105654-3-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
2025-09-24 14:29:14 -07:00
Marc Zyngier
181ce6b01a Merge branch kvm-arm64/misc-6.18 into kvmarm-master/next
* kvm-arm64/misc-6.18:
  : .
  : .
  : Misc improvements and bug fixes:
  :
  : - Fix XN handling in the S2 page table dumper
  :   (20250809135356.1003520-1-r09922117@csie.ntu.edu.tw)
  :
  : - Fix sanitity checks for huge mapping with pKVM running np guests
  :   (20250815162655.121108-1-ben.horgan@arm.com)
  :
  : - Fix use of TRBE when KVM is disabled, and Linux running under
  :   a lesser hypervisor (20250902-etm_crash-v2-1-aa9713a7306b@oss.qualcomm.com)
  :
  : - Fix out of date MTE-related comments (20250915155234.196288-1-alexandru.elisei@arm.com)
  :
  : - Fix PSCI BE support when running a NV guest (20250916161103.1040727-1-maz@kernel.org)
  :
  : - Fix page reference leak when refusing to map a page due to mismatched attributes
  :   (20250917130737.2139403-1-tabba@google.com)
  :
  : - Add trap handling for PMSDSFR_EL1
  :   (20250901-james-perf-feat_spe_eft-v8-7-2e2738f24559@linaro.org)
  :
  : - Add advertisement from FEAT_LSFE (Large System Float Extension)
  :   (20250918-arm64-lsfe-v4-1-0abc712101c7@kernel.org)
  : .
  KVM: arm64: Expose FEAT_LSFE to guests
  KVM: arm64: Add trap configs for PMSDSFR_EL1
  KVM: arm64: Fix page leak in user_mem_abort()
  KVM: arm64: Fix kvm_vcpu_{set,is}_be() to deal with EL2 state
  KVM: arm64: Update stale comment for sanitise_mte_tags()
  KVM: arm64: Return early from trace helpers when KVM isn't available
  KVM: arm64: Fix debug checking for np-guests using huge mappings
  KVM: arm64: ptdump: Don't test PTE_VALID alongside other attributes

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 12:26:29 +01:00
Marc Zyngier
47f15744fc Merge branch kvm-arm64/nv-misc-6.18 into kvmarm-master/next
* kvm-arm64/nv-misc-6.18:
  : .
  : Various NV-related fixes:
  :
  : - Relax KVM's SError injection to consider that HCR_EL2.AMO's
  :   effective value is 1 when HCR_EL2.{E2H,TGE)=={1,0}.
  :   (20250918164632.410404-1-oliver.upton@linux.dev)
  :
  : - Allow userspace to disable some S2 base granule sizes
  :   (20250918165505.415017-1-oliver.upton@linux.dev)
  : .
  KVM: arm64: nv: Allow userspace to de-feature stage-2 TGRANs
  KVM: arm64: nv: Treat AMO as 1 when at EL2 and {E2H,TGE} = {1, 0}

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 12:26:24 +01:00
Marc Zyngier
46bd74ef07 Merge branch kvm-arm64/el2-feature-control into kvmarm-master/next
* kvm-arm64/el2-feature-control: (23 commits)
  : .
  : General rework of EL2 features that can be disabled to satisfy
  : the requirement of migration between heterogeneous hosts:
  :
  : - Handle effective RES0 behaviour of undefined registers, making sure
  :   that disabling a feature affects full registeres, and not just
  :   individual control bits. (20250918151402.1665315-1-maz@kernel.org)
  :
  : - Allow ID_AA64MMFR1_EL1.{TWED,HCX} to be disabled from userspace.
  :   (20250911114621.3724469-1-yangjinqian1@huawei.com)
  :
  : - Turn the NV feature management into a deny-list, and expose
  :   missing features to EL2 guests.
  :   (20250912212258.407350-1-oliver.upton@linux.dev)
  : .
  KVM: arm64: nv: Expose up to FEAT_Debugv8p8 to NV-enabled VMs
  KVM: arm64: nv: Advertise FEAT_TIDCP1 to NV-enabled VMs
  KVM: arm64: nv: Advertise FEAT_SpecSEI to NV-enabled VMs
  KVM: arm64: nv: Expose FEAT_TWED to NV-enabled VMs
  KVM: arm64: nv: Exclude guest's TWED configuration when TWE isn't set
  KVM: arm64: nv: Expose FEAT_AFP to NV-enabled VMs
  KVM: arm64: nv: Expose FEAT_ECBHB to NV-enabled VMs
  KVM: arm64: nv: Expose FEAT_RASv1p1 via RAS_frac
  KVM: arm64: nv: Expose FEAT_DF2 to NV-enabled VMs
  KVM: arm64: nv: Don't erroneously claim FEAT_DoubleLock for NV VMs
  KVM: arm64: nv: Convert masks to denylists in limit_nv_id_reg()
  KVM: arm64: selftests: Test writes to ID_AA64MMFR1_EL1.{HCX, TWED}
  KVM: arm64: Make ID_AA64MMFR1_EL1.{HCX, TWED} writable from userspace
  KVM: arm64: Convert MDCR_EL2 RES0 handling to compute_reg_res0_bits()
  KVM: arm64: Convert SCTLR_EL1 RES0 handling to compute_reg_res0_bits()
  KVM: arm64: Enforce absence of FEAT_TCR2 on TCR2_EL2
  KVM: arm64: Enforce absence of FEAT_SCTLR2 on SCTLR2_EL{1,2}
  KVM: arm64: Convert HCR_EL2 RES0 handling to compute_reg_res0_bits()
  KVM: arm64: Enforce absence of FEAT_HCX on HCRX_EL2
  KVM: arm64: Enforce absence of FEAT_FGT2 on FGT2 registers
  ...

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 12:26:18 +01:00
Marc Zyngier
f01c7baa16 Merge branch kvm-arm64/nv-debug into kvmarm-master/next
* kvm-arm64/nv-debug:
  : .
  : Fix handling of MDSCR_EL1 in NV context, which is unfortunately
  : mishandled by the architecture. Patches courtesy of Oliver Upton
  : (20250917203125.283116-2-oliver.upton@linux.dev)
  : .
  KVM: arm64: nv: Apply guest's MDCR traps in nested context
  KVM: arm64: nv: Trap debug registers when in hyp context

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 12:26:11 +01:00
Marc Zyngier
d9476fd356 Merge branch kvm-arm64/gic-v5-nv into kvmarm-master/next
* kvm-arm64/gic-v5-nv:
  : .
  : Add NV support to GICv5 in GICv3 emulation mode, ensuring that the v3
  : guest support is identical to that of a pure v3 platform.
  :
  : Patches courtesy of Sascha Bischoff (20250828105925.3865158-1-sascha.bischoff@arm.com)
  : .
  irqchip/gic-v5: Drop has_gcie_v3_compat from gic_kvm_info
  KVM: arm64: Use ARM64_HAS_GICV5_LEGACY for GICv5 probing
  arm64: cpucaps: Add GICv5 Legacy vCPU interface (GCIE_LEGACY) capability
  KVM: arm64: Enable nested for GICv5 host with FEAT_GCIE_LEGACY
  KVM: arm64: Don't access ICC_SRE_EL2 if GICv3 doesn't support v2 compatibility

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 12:26:05 +01:00
Marc Zyngier
8cba6c8b87 Merge branch kvm-arm64/52bit-at into kvmarm-master/next
* kvm-arm64/52bit-at:
  : .
  : Upgrade the S1 page table walker to support 52bit PA, and use it to
  : report the fault level when taking a S2 fault on S1PTW, which is required
  : by the architecture (20250915114451.660351-1-maz@kernel.org).
  : .
  KVM: arm64: selftest: Expand external_aborts test to look for TTW levels
  KVM: arm64: Populate level on S1PTW SEA injection
  KVM: arm64: Add S1 IPA to page table level walker
  KVM: arm64: Add filtering hook to S1 page table walk
  KVM: arm64: Don't switch MMU on translation from non-NV context
  KVM: arm64: Allow EL1 control registers to be accessed from the CPU state
  KVM: arm64: Allow use of S1 PTW for non-NV vcpus
  KVM: arm64: Report faults from S1 walk setup at the expected start level
  KVM: arm64: Expand valid block mappings to FEAT_LPA/LPA2 support
  KVM: arm64: Populate PAR_EL1 with 52bit addresses
  KVM: arm64: Compute shareability for LPA2
  KVM: arm64: Pass the walk_info structure to compute_par_s1()
  KVM: arm64: Decouple output address from the PT descriptor
  KVM: arm64: Compute 52bit TTBR address and alignment
  KVM: arm64: Account for 52bit when computing maximum OA
  KVM: arm64: Add helper computing the state of 52bit PA support

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 12:25:57 +01:00
Marc Zyngier
50f77dc87f KVM: arm64: Populate level on S1PTW SEA injection
Our fault injection mechanism is mildly primitive, and doesn't
really implement the architecture when it comes to reporting
the level of a failing S1 PTW (we blindly report a SEA outside
of a PTW).

Now that we can walk the S1 page tables and look for a particular
IPA in the descriptors, it is pretty easy to improve the SEA
injection code.

Note that we only do it for AArch64 guests, and that 32bit guests
are left to their own device (oddly enough, I don't fancy writing
a 32bit PTW...).

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 11:05:14 +01:00
Marc Zyngier
b8e625167a KVM: arm64: Add S1 IPA to page table level walker
Use the filtering hook infrastructure to implement a new walker
that, for a given VA and an IPA, returns the level of the first
occurence of this IPA in the walk from that VA.

This will be used to improve our SEA syndrome reporting.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 11:05:14 +01:00
Marc Zyngier
0c5471408c KVM: arm64: Add filtering hook to S1 page table walk
Add a filtering hook that can get called on each level of the
walk, and providing access to the full state.

Crucially, this is called *before* the access is made, so that
it is possible to track down the level of a faulting access.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 11:05:13 +01:00
Marc Zyngier
61b0280a67 KVM: arm64: Don't switch MMU on translation from non-NV context
If calling into the AT code from guest EL1, there is no need
to consider any context switch, as we are guaranteed to be
in the correct context.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 11:05:13 +01:00
Marc Zyngier
cb1762904c KVM: arm64: Allow EL1 control registers to be accessed from the CPU state
As we are about to plug the SW PTW into the EL1-only code, we can
no longer assume that the EL1 state is not resident on the CPU,
as we don't necessarily get there from EL2 traps.

Turn the __vcpu_sys_reg() access on the EL1 state into calls to
the vcpu_read_sys_reg() helper, which is guaranteed to do the
right thing.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 11:05:13 +01:00
Marc Zyngier
14d4802dc2 KVM: arm64: Allow use of S1 PTW for non-NV vcpus
As we are about to use the S1 PTW in non-NV contexts, we must make
sure that we don't evaluate the EL2 state when dealing with the EL1&0
translation regime.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 11:05:13 +01:00
Marc Zyngier
dabf9f73fe KVM: arm64: Report faults from S1 walk setup at the expected start level
Translation faults from TTBR must be reported on the start level,
and not level-0. Enforcing this requires moving quite a lot of
code around so that the start level can be computed early enough
that it is usable.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-09-20 11:05:13 +01:00