Pull random number generator fixes from Jason Donenfeld:

 - VMGENID memory needs to be mapped with the decrypted tag, so that
   SEV-SNP machines can boot

 - A fix for an initialization race in VMGENID, followed by a cleanup

 - Trivial kernel doc cleanups in siphash and random.c

 - A fix for a new compilation failure with recent clang on PPC and
   RISC-V, due to generating an out-of-line memset in the vDSO

* tag 'random-7.3-rc6-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random:
  random: vDSO: avoid call to memset() when zeroing reserved parameter
  random: fix vgetrandom_opaque_params kernel-doc
  random: vDSO: fix repeated word 'to' in comment
  siphash: clean up kernel-doc comments
  virt: vmgenid: move to using dev_set/get_drvdata
  virt: vmgenid: set driver_data before registering notification handlers
  virt: vmgenid: remap memory as decrypted

After a recent change in LLVM [1], builds with the random vDSO
implementation, such as PowerPC and RISC-V, fail when checking the vDSO:

  arch/powerpc/kernel/vdso/vdso32.so.dbg: dynamic relocations are not supported
  arch/riscv/kernel/vdso/vdso.so.dbg: dynamic relocations are not supported

memset() is now generated when zeroing params->reserved for some builds
because LLVM has an optimization (now run in more instances) that can
recognize at compile time when it is assigning a static value to a
contiguous area of memory and turn that into a call to memset(). Both
clang and GCC assume memset() is always available [2].

Clang has an internal fiddly hook, -max-store-memset, which we can set
to a high number, to disable generating out of line memset calls [3].
Similarly, GCC has -finline-stringops=memset to do the same [4], should
this issue ever hit future version of GCC. While these options wouldn't
make sense for normal kernel code, it is fine for the extremely limited
and intentionally compact vDSO code.

Link: https://github.com/llvm/llvm-project/commit/90cebef1411617fc3eedd359bdf00cb44b1c2439 [1]
Link: https://gcc.gnu.org/onlinedocs/gcc-16.2.0/gcc/Standards.html#index-ffreestanding [2]
Link: https://github.com/llvm/llvm-project/commit/b28eeb28bea39148738dc375e8a97072a1907e64 [3]
Link: https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html#index-finline-stringops [4]
Closes: https://github.com/ClangBuiltLinux/linux/issues/2183
Cc: stable@vger.kernel.org # v6.12+
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

Pull kvm fixes from Paolo Bonzini:
 "Arm:

   - Invalidate the ITS translation cache when the guest changes the
     base address of the ITS tables (Fuad Tabba)

   - Skip saving ITS devices with device IDs that are out-of-bounds
     rather than failing the entire ITS save ioctl (Fuad Tabba)

   - Close race between VM teardown and invalidations of nested MMUs
     when handling MMU operations that are allowed to block (Lorenzo
     Stoakes)

   - Various fixes for the handling of the host's untrusted SVE
     configuration in pKVM (Fuad Tabba)

   - Make sure that empty SMCCC ranges based at 0 are rejected by the
     kvm_smccc_set_filter() (Karl Mehltretter)

   - Revoke the host mapping for pKVM's private stack pages, along with
     a new sanity check that all mappings in the hyp's private VA range
     have been correctly marked as hyp-owned (Fuad Tabba)

   - Lifetime fixes for the array of shadow stage-2 MMUs, ensuring that
     concurrent vCPU initialization cannot relocate in-use MMUs. Defer
     the freeing of shadow stage-2 MMUs to the point that no other users
     (e.g. MMU notifier) could reference them (Marc Zyngier)

   - Drop useless WARN when rejecting an unsupported ioctl for pKVM
     (Fuad Tabba)

   - Fix the steal_time selftest to install correctly-sized mappings for
     non-4K hosts (Sebastian Ott)

   - Correct mapping of fine-grained trap for GCSPOPX instruction (Mark
     Brown)

   - Fix KVM_BUG_ON() due to missing handling of DBGBXVR<n> from 32-bit
     guests (Karl Mehltretter)

  RISC-V:

   - Synchronize hrtimer during VCPU teardown

   - Fix the conversion between vsip and hvip values

   - Serialize IMSIC attributes with vCPU migration

   - Release unused page after MMU invalidation

   - Propagate interrupted G-stage faults to KVM user-space as EINTR

   - Fix nested acceleration hfence entry update order

   - Fix sdata leak and stale snapshot_addr in snapshot_set_shmem

   - Preserve firmware counter value across PMU counter stop/start

   - Report PMU snapshot write failure to the guest

   - Fix perf-backed counter accounting across PMU stop and read

   - Correctly propagate error of a hart status SBI call

  s390:

   - Ensure that accesses through kvm_arch_set_irq_inatomic mark as
     dirty the pages that contain indicator and summary bits

   - Fix compile warning for kvm_s390_update_cmma_dirty()

   - Fix incorrect propagation of ENOENT from _gaccess_shadow_fault() to
     userspace

   - Move s390_kvm_mmu_commit_memory_region() into
     s390_kvm_mmu_prepare_memory_region() so that it can fail instead of
     WARN

   - Add missing srcu in kvm_s390_set_irq_state()

   - Fix potential races in storage functions

   - Fix race in _destroy_pages_crste()

   - Fix issues in the handling of KVM interrupt and page resources,
     when a queue that is assigned to a mediated device (mdev) is
     removed from the host's AP configuration

   - Fix loop condition in uv_find_secrets

   - Prevent potential out-of-bounds read

  x86:

   - Fix a brown paper bag bug where KVM would incorrectly treat Intel
     PMU MSRs as valid on AMD

   - Fix a regression in the hardware disable selftest where it checked
     the wrong macro when detecting glibc support (breaks at least musl)

   - Never clear KVM_REQ_VM_DEAD so that dead VMs stay dead, which is
     especially important for KVM_BUG_ON() flows, which often guard more
     dangerous bugs

   - Re-pend GET_NESTED_STATE_PAGES if getting the pages fails, to fix a
     bug where KVM would let userspace run a broken setup with stale
     vmcs12 pages

   - Fix a class of bugs where KVM would fail to fill kvm_run exit
     fields if getting nested pages failed

   - Treat reserved entries in the memory attributes xarray as "no
     attributes", to fix false positives when checking for mixed
     attributes

   - Fix memcg accounting for the memory attributes xarray (the xarray
     library subtly requires the xarray to be configured for accounting
     upfront; the gfp flags taken at runtime are used only rarely)

   - Don't pre-reserve xarray entries when storing empty attributes, as
     storing NULL must not require memory allocation (KVM and other
     subsystems heavily rely on this behavior)

   - Fix a memory leak and a cache maintenance issue related to doing
     intra-host migration on an SEV guest"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (54 commits)
  KVM: SEV: Do cache maintenance on the source VM during intra-host migration
  KVM: SEV: Free have_run_cpus during VM destruction even if VM is no longer SEV
  KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes
  KVM: Ensure memory attributes xarray nodes are accounted to the caller's memcg
  KVM: Don't treat reserved xarray entries as having memory attributes
  KVM: x86: Fill kvm_run exit fields in common get_nested_state_pages() error paths
  KVM: x86: Re-pend GET_NESTED_STATE_PAGES if getting said pages fails
  KVM: arm64: Fix AArch32 DBGBXVR<n> handling
  KVM: arm64: Fix FGT mapping for HFGITR_EL2.nGCSEPP
  KVM: selftests: fix steal_time for arm64 with host page size > 4K
  KVM: arm64: Don't WARN on an unknown VM ioctl in protected mode
  KVM: arm64: nv: Delay freeing of shadow S2 structures until VM destruction
  KVM: arm64: nv: Fix life cycle of the nested_mmus array
  KVM: arm64: Check every private mapping is hyp-owned at pKVM init
  KVM: arm64: Move the private VA allocation cursor to __io_map_next
  KVM: arm64: Match hyp text by physical address in fix_host_ownership()
  KVM: arm64: Transfer the hyp stack pages out of the host stage-2
  KVM: arm64: selftests: Test empty SMCCC filter range at base 0
  KVM: arm64: Return -EINVAL for an empty SMCCC filter range at base 0
  KVM: arm64: Derive GUEST_HAS_SVE from the SVE feature bit at EL2
  ...

When debug_register_static() fails, it clears areas, active_pages and
active_entries but leaves the area bounds unchanged. Copying such an
area, either by opening its view file or via debug_dump(), makes
debug_info_copy() dereference the NULL pointers.

Skip the copy loop when the source has no areas.

Closes: https://lore.kernel.org/r/20260903132123.12F271F00A3F@smtp.kernel.org
Fixes: d72541f94512 ("s390/debug: add early tracing support")
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

__REGISTER_STATIC_DEBUG_INFO() calls debug_register_view()
unconditionally, even when debug_register_static() has failed. In that
case _debug_register() was never reached and id->debugfs_root_entry is
still NULL, so debugfs_create_file() places the view file in the debugfs
root directory. For sclp_err this leaves a /sys/kernel/debug/hex_ascii
file with nothing to indicate which debug log it belongs to.

debug_register_static() is not exported and the macro is its only
caller, so let it return an error code and skip the view registration
when it fails. No debugfs files are created for such an area then.

Reproduce by booting with s390dbf=sclp_err::100000000. The sclp_err
registration fails, no s390dbf/sclp_err/ directory is created, and a
hex_ascii file appears in the debugfs root instead.

Fixes: d72541f94512 ("s390/debug: add early tracing support")
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

debug_dump() passes id on to debug_info_copy(), which dereferences
in->name unchecked. debug_unregister(), debug_set_size() and
debug_register_view() guard against a NULL id but debug_dump() does not.
Nothing reaches this today, but add the check for consistency.

Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://lore.kernel.org/all/20260910110147.96E851F000FF@smtp.kernel.org/
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

KVM/arm64 changes for 7.3, take #2

 - Invalidate the ITS translation cache when the guest changes the
   base address of the ITS tables (Fuad Tabba)

 - Skip saving ITS devices with device IDs that are out-of-bounds
   rather than failing the entire ITS save ioctl (Fuad Tabba)

 - Close race between VM teardown and invalidations of nested MMUs
   when handling MMU operations that are allowed to block
   (Lorenzo Stoakes)

 - Various fixes for the handling of the host's untrusted SVE
   configuration in pKVM (Fuad Tabba)

 - Make sure that empty SMCCC ranges based at 0 are rejected by the
   kvm_smccc_set_filter() (Karl Mehltretter)

 - Revoke the host mapping for pKVM's private stack pages, along
   with a new sanity check that all mappings in the hyp's private
   VA range have been correctly marked as hyp-owned (Fuad Tabba)

 - Lifetime fixes for the array of shadow stage-2 MMUs, ensuring that
   concurrent vCPU initialization cannot relocate in-use MMUs. Defer
   the freeing of shadow stage-2 MMUs to the point that no other users
   (e.g. MMU notifier) could reference them (Marc Zyngier)

 - Drop useless WARN when rejecting an unsupported ioctl for pKVM
   (Fuad Tabba)

 - Fix the steal_time selftest to install correctly-sized mappings for
   non-4K hosts (Sebastian Ott)

 - Correct mapping of fine-grained trap for GCSPOPX instruction
   (Mark Brown)

 - Fix KVM_BUG_ON() due to missing handling of DBGBXVR<n> from 32-bit
   guests (Karl Mehltretter)

Trace functions check for non-NULL id->areas without lock to minimize
overhead. This opens a race window where a NULL pointer dereference
occurs if id->areas is set to NULL (e.g. via echo 0 > ../pages) after
the check and before id->lock is taken.

Fix this by rechecking id->areas under lock.

Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

Commit a2cec6863709 ("s390/debug: Add s390dbf kernel parameter") calls
debug_get_param() from both debug_info_create() and debug_set_level().
Since debug_get_param() emits the override notice unconditionally, and
drivers typically call debug_set_level() right after debug_register(),
the same line is printed twice per debug area:

  s390dbf: 0.0.1234: override level to 6
  s390dbf: 0.0.1234: override level to 6

For areas registered per device this is multiplied by the device count.
With 's390dbf=0.0.*:6' a system with many DASDs emits a large number of
redundant lines during boot.

Add a quiet parameter to debug_get_param() and pass quiet=true from
debug_set_level(), where the override has already been announced during
registration. The remaining callers keep printing the notice.

Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

Commit a2cec6863709 ("s390/debug: Add s390dbf kernel parameter")
incorrectly removed a null-id check from debug_set_level(), introducing
a possible NULL pointer dereference for debug-API users that put
debug_register() results unchecked into debug_set_level().

Fix this by moving the check from the internal _debug_set_level()
variant back to the external debug_set_level() wrapper.

Fixes: a2cec6863709 ("s390/debug: Add s390dbf kernel parameter")

Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>