Commit Graph

246222 Commits

Author SHA1 Message Date
Linus Torvalds
b96890b3e5 Merge tag 'powerpc-7.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Madhavan Srinivasan:

 - ensure vpa,slb_shadow & dtl are unregistered during crash

 - fix nap return address corruption on async interrupt exit in 970
   platform

 - fix exit_flags field placement in pt_regs for ptrace

 - fix map failure path in dma_ioc0_map_pages() in ps3 platfrom

 - MAINTAINERS: Michael Ellerman demotes himself to reviewer

 - misc fixes and cleanup

Thanks to Amit Machhiwal, Andreas Schwab, Anushree Mathur, Athira
Rajeev, Christophe Leroy (CS GROUP), Dmitry V. Levin, Geert
Uytterhoeven, John Ogness, Michael Ellerman, Mukesh Kumar Chaurasiya
(IBM), Ritesh Harjani (IBM), Thorsten Blum, and Vaibhav Jain

* tag 'powerpc-7.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  MAINTAINERS: Demote myself to reviewer
  powerpc/serial: Fix include guard comment
  powerpc/perf: Use strstarts() to simplify is_thread_imc_pmu()
  powerpc/ps3: Fix map failure path in dma_ioc0_map_pages()
  powerpc/ps3: Remove unused struct table in setup_areas()
  powerpc/boot: Fix treeboot-akebono CPU node lookup check
  powerpc/boot: Fix treeboot-currituck CPU node lookup check
  powerpc/boot: Fix simpleboot CPU node lookup check
  powerpc: Fix exit_flags field placement in pt_regs for ptrace
  powerpc/970: fix nap return address corruption on async interrupt exit
  powerpc/pseries: Skip vpa_init() for boot cpu in smp_setup_cpu()
  powerpc/pseries: Ensure vpa,slb_shadow & dtl are unregistered during crash
2026-07-30 08:24:12 -07:00
Sean Christopherson
7d3aae2066 KVM: SVM: Update x2APIC MSR intercepts if AVIC is inhibited while L2 is active
Always update x2APIC MSR intercepts for L1 when AVIC is deactivated, even
if L2 is active and KVM is using a separate MSR bitmap to run L2.  If AVIC
is fully enabled prior to running L2, and is then inhibited while L2 is
active (for a VM-scoped inhibit), then KVM will run L1 with AVIC disabled,
but with x2APIC MSR intercepts disabled, i.e. will allow L1 to read most of
the host's APIC state, send arbitrary interrupts, change task priority, and
ultimately trivially DoS the host.

E.g. sending a self-IPI in L1 on HYPERV_REENLIGHTENMENT_VECTOR, 0xee, with
CONFIG_HYPERV=n in the host kernel as a "safe" PoC, yields:

  Spurious interrupt (vector 0xee) on CPU#425. Acked

And hacking KVM to abuse kvm_set_posted_intr_wakeup_handler() to register a
handler and WARN on POSTED_INTR_WAKEUP_VECTOR yields:

  ------------[ cut here ]------------
  WARNING: arch/x86/kvm/svm/svm.c:5594 at pi_wakeup_handler+0x9/0x10 [kvm_amd], CPU#156: nested_x2apic_t/316940
  CPU: 156 UID: 0 PID: 316940 Comm: nested_x2apic_t Tainted: G S   U
  Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER
  Hardware name: Google Astoria-Turin/astoria, BIOS 0.20260209.0-0 02/09/2026
  RIP: 0010:pi_wakeup_handler+0x9/0x10 [kvm_amd]
  Call Trace:
   <IRQ>
   sysvec_kvm_posted_intr_wakeup_ipi+0x64/0x80
   </IRQ>
   <TASK>
   asm_sysvec_kvm_posted_intr_wakeup_ipi+0x1a/0x20
  RIP: 0010:vcpu_run+0x1430/0x1e40 [kvm]
   kvm_arch_vcpu_ioctl_run+0x2c1/0x600 [kvm]
   kvm_vcpu_ioctl+0x580/0x6b0 [kvm]
   __se_sys_ioctl+0x6d/0xb0
   do_syscall_64+0x10a/0x480
   entry_SYSCALL_64_after_hwframe+0x4b/0x53
  RIP: 0033:0x46ff4b
   </TASK>
  ---[ end trace 0000000000000000 ]---

Fixes: 091abbf578 ("KVM: x86: nSVM: optimize svm_set_x2apic_msr_interception")
Cc: stable@vger.kernel.org
Cc: Yosry Ahmed <yosry@kernel.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://patch.msgid.link/20260729213558.639074-1-pbonzini@redhat.com/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2026-07-29 23:39:36 +02:00
Jinu Kim
2e8a2c1b03 KVM: x86/mmu: Check all address spaces before skipping unsync
mmu_try_to_unsync_pages() skips the shadow-page lookup when the
supplied memslot allows a hugepage, because a shadow page would disallow
hugepages.  But hugepage metadata is per-address-space while shadow pages
are shared across all address spaces.  With SMM, the other address space
can therefore have a shadow page even when the supplied memslot allows a
hugepage.

Check the corresponding memslot in the other address space before
taking the fast path.  Skip the shadow-page lookup only when all address
spaces allow a hugepage.

Fixes: b3ae3ceb55 ("KVM: x86/mmu: KVM: x86/mmu: Skip unsync when large pages are allowed")
Assisted-by: Codex:GPT-5
Signed-off-by: Jinu Kim <kimjw04271234@gmail.com>
[invert direction of the conditional. - Paolo]
Message-ID: <20260721103512.2136240-3-kimjw04271234@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2026-07-28 18:07:18 +02:00
Jinu Kim
0f38453cdb KVM: x86/mmu: Check write tracking in all address spaces
kvm_gfn_is_write_tracked() checks only the supplied memslot, but page
tracking is per-address-space and shadow pages are shared across all
address spaces.  With SMM, a GFN can therefore be write-tracked in one
address space and appear untracked through the other.

Check the supplied slot first, then the slot for the other address space.
This ensures all callers honor write tracking regardless of the active
address space.  In particular, it prevents mmu_try_to_unsync_pages() from
marking an upper-level shadow page unsync and eventually triggering the
BUG in pte_list_remove().

Fixes: 699023e239 ("KVM: x86: add SMM to the MMU role, support SMRAM address space")
Assisted-by: Codex:GPT-5
Signed-off-by: Jinu Kim <kimjw04271234@gmail.com>
Message-ID: <20260721103512.2136240-2-kimjw04271234@gmail.com>
[invert direction of the conditional. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2026-07-28 18:07:14 +02:00
Weiming Shi
9910e83558 KVM: x86: Cancel delayed I/O APIC EOI handling before destroying vCPUs
Cancel (and flush) the I/O APIC's delayed EOI handling work during the
"pre VM destroy" phase, before vCPUs are destroyed, as processing the EOI
broadcast will inject another IRQ if the line is asserted, i.e. will try
to deliver an IRQ to the target vCPU(s).  Canceling the work after vCPUs
are destroyed leads to UAF if the delayed work is processed after vCPUs are
destroyed.

  BUG: KASAN: slab-use-after-free in __kvm_irq_delivery_to_apic_fast+0x9bf/0xa20 arch/x86/kvm/lapic.c:1250
  Read of size 8 at addr ffff8880499abea0 by task kworker/1:2/1218

  CPU: 1 UID: 0 PID: 1218 Comm: kworker/1:2 Not tainted 7.1.0-rc7 #5 PREEMPT(lazy)
  Hardware name: QEMU Ubuntu 25.10 PC v2 (i440FX + PIIX, + 10.1 machine, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
  Workqueue: events kvm_ioapic_eoi_inject_work
  Call Trace:
   <TASK>
   __dump_stack lib/dump_stack.c:94
   dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
   print_address_description mm/kasan/report.c:378
   print_report+0x139/0x4ad mm/kasan/report.c:482
   kasan_report+0xe4/0x1d0 mm/kasan/report.c:595
   __kvm_irq_delivery_to_apic_fast+0x9bf/0xa20 arch/x86/kvm/lapic.c:1250
   __kvm_irq_delivery_to_apic+0xd8/0xbf0 arch/x86/kvm/lapic.c:1345
   kvm_irq_delivery_to_apic arch/x86/kvm/lapic.h:129
   ioapic_service+0x308/0x590 arch/x86/kvm/ioapic.c:492
   kvm_ioapic_eoi_inject_work+0x13c/0x190 arch/x86/kvm/ioapic.c:532
   process_one_work+0xa59/0x19a0 kernel/workqueue.c:3314
   process_scheduled_works kernel/workqueue.c:3397
   worker_thread+0x5eb/0xe50 kernel/workqueue.c:3478
   kthread+0x370/0x450 kernel/kthread.c:436
   ret_from_fork+0x72b/0xd30 arch/x86/kernel/process.c:158
   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
   </TASK>

Note, the VM is unreachable once kvm_destroy_vm() starts, and scheduling
new work via kvm_ioapic_send_eoi() can only be done via KVM_RUN, i.e.
requires a live vCPU.

Alternatively, KVM could simply destroy the I/O APIC during the "pre" phase
of VM destruction, but that gets more than a bit sketchy as KVM expects the
I/O APIC to exist if ioapic_in_kernel() is true, and nested virtualization
in particular has a bad habit of touching VM-scope state during vCPU
destruction.  E.g. attempting to free the PIC during the pre phase would
lead to a NULL pointer dereference in kvm_cpu_has_extint(), and it's not
hard to imagine the I/O APIC having a similar flaw.

Fixes: 17bcd71442 ("KVM: x86: Free vCPUs before freeing VM state")
Reported-by: <zdi-disclosures@trendmicro.com>
Reported-by: Zhong Wang <wangzhong.c0ss4ck@bytedance.com>
Reported-by: Xuanqing Shi <shixuanqing.11@bytedance.com>
Cc: stable@vger.kernel.org
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20260727171718.543491-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2026-07-28 17:43:28 +02:00
Paolo Bonzini
0e65cd9e5d KVM: VMX: add memory clobber to asm for VMX instructions
VMCLEAR/VMREAD/VMWRITE/VMPTRLD access the internal VMCS cache, which
is not visible to the compiler; without a memory clobber, the compiler
can reorder them in troublesome ways because "asm volatile" and "asm goto"
only protect against removal of the asm.  For example, placing a VMWRITE
before the corresponding VMCS pointer is loaded can lead to corruption.
While none of this has been observed, it is better to prevent than cure.

Likewise, INVEPT and INVVPID access the TLB and, even though in their
case the effect is only visible to the next VMLAUNCH/VMRESUME, it is
technically correct to add the clobber there too.  So avoid any urge to
special case them, and simply hardcode "memory" into the clobber list
of vmx_asm1() and vmx_asm2().  __vmcs_readl() open-codes its own asm,
so add the clobber there as well.

Link: https://lore.kernel.org/kvm/CABgObfbL3t21yVeSwiLSjjOUER+rTYDPHYAH9YU4TWGRjx6XHg@mail.gmail.com/
Cc: Sean Christopherson <seanjc@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2026-07-28 17:43:28 +02:00
Paolo Bonzini
a7fe52b5ab Merge tag 'kvmarm-fixes-7.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 fixes for 7.2, take #3

- Fix a tiny buglet when propagating the deactivation of an interrupt
  from a nested guest, which happened to trigger a gold plated CPU bug
  on a particular implementation

- Fix a race between LPI unmapping and mapping, resulting in leaked
  LPIs

- Make LPI mapping more robust on memory allocation failure

- Fix the handling of the EL2 tracing clock being disabled

- A couple of Sashiko-driven fixes for corner cases in the EL2 tracing
  code

- Add missing sysreg tracepoint for the EL2 code

- Tidy-up the mutual exclusion of guest-memfd and MTE

- Update Fuad's email address to point to @linux.dev
2026-07-28 17:43:23 +02:00
Paolo Bonzini
70f526a0f9 Merge tag 'kvm-s390-master-7.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
KVM: s390: Fixes for 7.2

- several fixes for PCI passthru in s390 kvm
- fix a 7.2-rc regression in the adapter interrupt mapping code
2026-07-28 17:43:18 +02:00
Thorsten Blum
86f057c19f powerpc/serial: Fix include guard comment
Replace _PPC64_SERIAL_H with _ASM_POWERPC_SERIAL_H to match the actual
macro name. Remove an empty comment while at it.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260623153825.403819-2-thorsten.blum@linux.dev
2026-07-28 10:23:32 +05:30
Thorsten Blum
d71b3ca523 powerpc/perf: Use strstarts() to simplify is_thread_imc_pmu()
Replace the open-coded implementation with strstarts() to simplify
is_thread_imc_pmu().

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Athira Rajeev <atrajeev@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260704121353.201583-3-thorsten.blum@linux.dev
2026-07-28 10:23:31 +05:30
Thorsten Blum
0bb024f11d powerpc/ps3: Fix map failure path in dma_ioc0_map_pages()
If lv1_put_iopte() fails in dma_ioc0_map_pages(), the error path
decrements iopage but keeps using the failed mapping's offset. As a
result, it repeatedly tries to invalidate the failed IOPTE slot and
leaves the already installed IOPTEs valid.

Recompute offset and invalidate the installed IOPTEs instead.

Fixes: 6bb5cf1025 ("[POWERPC] PS3: System-bus rework")
Cc: stable@vger.kernel.org
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260711130931.740719-3-thorsten.blum@linux.dev
2026-07-28 10:23:31 +05:30
Thorsten Blum
41bf83c1b1 powerpc/ps3: Remove unused struct table in setup_areas()
The local table structure is not used - remove it.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Amit Machhiwal <amachhiw@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260713091731.97212-3-thorsten.blum@linux.dev
2026-07-28 10:23:31 +05:30
Thorsten Blum
b24fc8278b powerpc/boot: Fix treeboot-akebono CPU node lookup check
fdt_node_offset_by_prop_value() returns a negative error code on
failure - fix the check accordingly.

Fixes: 2a2c74b2ef ("IBM Akebono: Add the Akebono platform")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260702211554.56923-6-thorsten.blum@linux.dev
2026-07-28 10:23:31 +05:30
Thorsten Blum
43863f6575 powerpc/boot: Fix treeboot-currituck CPU node lookup check
fdt_node_offset_by_prop_value() returns a negative error code on
failure - fix the check accordingly.

Fixes: 228d550533 ("powerpc/47x: Add support for the new IBM currituck platform")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260702211554.56923-5-thorsten.blum@linux.dev
2026-07-28 10:23:31 +05:30
Thorsten Blum
c824ab6568 powerpc/boot: Fix simpleboot CPU node lookup check
fdt_node_offset_by_prop_value() returns a negative error code on
failure - fix the check accordingly.

Fixes: d2477b5cc8 ("[POWERPC] bootwrapper: Add a firmware-independent simpleboot target.")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260702211554.56923-4-thorsten.blum@linux.dev
2026-07-28 10:23:31 +05:30
Mukesh Kumar Chaurasiya (IBM)
263e5159e0 powerpc: Fix exit_flags field placement in pt_regs for ptrace
Commit d7a6797e0b ("powerpc: add exit_flags field in pt_regs") added
the exit_flags field to struct pt_regs to pass internal exit control
flags (e.g. _TIF_RESTOREALL) from syscall_exit_prepare() to the
low-level assembly exit path.

However, the field was placed in a way that was visible to userspace
tools such as strace via PTRACE_GETREGS, or caused a struct layout or
size regression observable through ptrace. The field is purely
kernel-internal and must not be exposed beyond the user_pt_regs
boundary.

Move exit_flags into struct thread_info where it is only accessible to
the kernel, and keep it out of the ptrace-visible register window
entirely.

Fixes: d7a6797e0b ("powerpc: add exit_flags field in pt_regs")
Reported-by: Dmitry V. Levin <ldv@strace.io>
Closes: https://lore.kernel.org/all/20260722070155.GA11808@strace.io/
Signed-off-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260723194809.4046600-1-mkchauras@gmail.com
2026-07-28 10:23:31 +05:30
Mukesh Kumar Chaurasiya (IBM)
bddf754009 powerpc/970: fix nap return address corruption on async interrupt exit
On PowerMac G5 (PPC970, CONFIG_PPC_970_NAP) the system panics shortly
after boot with symptoms including instruction fetch faults, kernel data
access faults, and stack corruption, predominantly on SMP and always
somewhere inside softirq processing.

The PPC970 idle path works by setting _TLF_NAPPING in the current
thread's local flags before entering the MSR_POW nap loop.  When any
async interrupt wakes the CPU, nap_adjust_return() is expected to detect
_TLF_NAPPING, clear it, and rewrite regs->NIP to power4_idle_nap_return
so that the interrupt returns cleanly to the caller of power4_idle_nap()
rather than back into the nap spin loop.

DEFINE_INTERRUPT_HANDLER_ASYNC generates the following sequence:

    irq_enter_rcu();
    ____func(regs);           /* timer_interrupt / do_IRQ body */
    irq_exit_rcu();           /* softirqs run here, irqs re-enabled */
    arch_interrupt_async_exit_prepare(regs); /* nap_adjust_return was here */
    irqentry_exit(regs, state);

irq_exit_rcu() calls invoke_softirq() -> do_softirq_own_stack(), which
runs softirqs with hardware interrupts re-enabled.  A nested async
interrupt can therefore arrive while _TLF_NAPPING is still set.  That
nested interrupt reaches nap_adjust_return() in its own
arch_interrupt_async_exit_prepare() call, finds _TLF_NAPPING set, and
redirects *its own* regs->NIP to power4_idle_nap_return.  Returning via
that blr with an unrelated LR on the softirq stack jumps to a garbage
address, causing the observed crashes.

The comment that previously lived in arch_interrupt_async_exit_prepare()
even described this exact hazard ("must come before irq_exit()"), but
nap_adjust_return() was placed after irq_exit_rcu() in the macro, so
the protection was never effective.

Fix this by calling nap_adjust_return() inside DEFINE_INTERRUPT_HANDLER_ASYNC
immediately before irq_exit_rcu(), ensuring _TLF_NAPPING is cleared and
regs->NIP is adjusted before any code that can re-enable interrupts or
invoke softirqs runs.  Move the explanatory comment into
nap_adjust_return() itself and remove it from arch_interrupt_async_exit_prepare().

Fixes: bee25f97ad ("powerpc: Enable GENERIC_ENTRY feature")
Closes: https://lore.kernel.org/all/87wlvazrdy.fsf@igel.home/
Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com>
Tested-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260707172430.790040-1-mkchauras@gmail.com
2026-07-28 10:23:31 +05:30
Vaibhav Jain
8f45abd50a powerpc/pseries: Skip vpa_init() for boot cpu in smp_setup_cpu()
During pSeries_setup_arch(), VPA for boot-cpu is first to be
initialized. However later in the boot, smp_setup_cpu() is called for
setting up VPA on boot and secondary cpus that were brought online. This
results in vpa_init() being called twice for boot-cpu and three redundant
H_REGISTER_VPA hcalls being made to the hypervisor.

Fix this by adding an extra condition in smp_set_cpu() to call vpa_init()
only on non boot-cpus.

Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260708015842.274690-1-vaibhav@linux.ibm.com
2026-07-28 10:08:32 +05:30
Vaibhav Jain
810d07fb4c powerpc/pseries: Ensure vpa,slb_shadow & dtl are unregistered during crash
Currently pseries_kexec_cpu_down() skips unregistering vpa, slb_shadow and
dtl areas during a crash and kexec shutdown path. It was done to avoid
doing an HCALL while crashing. However recently Anushree reported that
during kernel crash while the kdump kernel was coming up, Hypervisor
reported invalid values for 'vpa.yield_count' while it dispatching L2-KVM
Guest vcpus. The error manifested as debug build Hypervisor assert
triggering to indicate possible VPA corruption.

Looking at the kexec cpu offline path it was discovered that during crash
kernel doesn't unregister the VPA/SLB-Shadow/DTL area with
Hypervisor. Instead it re-allocates and re-registers these areas
for cpus during boot. During kexec boot the previously allocated areas
can get overwritten with new content without hypervisor knowledge. This
creates a small window where while kexec kernel boots and the L2-VCPUs are
being dispatched, Hypervisor may try to read/write to a wrong memory area
which previously belonged to older VPA.

Fix this possible race and memory corruption by updating
pseries_kexec_cpu_down() to also unregister vpa,slb_shadow & dtl areas
during a kernel crash.

Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Tested-by: Anushree Mathur <anushree.mathur@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260708015802.274271-1-vaibhav@linux.ibm.com
2026-07-28 10:07:39 +05:30
Jaehoon Kim
9972befc3e KVM: s390: Fall back to short-term pinning in MAP ioctl
FOLL_LONGTERM pinning fails for some memory types, such as file-backed
guest memory. As a result, kvm_s390_adapter_map() returns -EINVAL and
irqfd adapter registration fails even though interrupt delivery could
still work via the existing non-atomic path.

When FOLL_LONGTERM pinning fails, verify that the page is accessible
using a short-term pin instead. If the short-term pin succeeds, unpin
the page and add a map entry with pinned=false to preserve MAP/UNMAP
symmetry. The non-atomic irqfd path already performs short-term pinning
for interrupt delivery, so this restores the previous behavior for
memory that cannot be pinned long-term.

get_map_info() is updated to return NULL for unpinned entries so that
the atomic irqfd fast path falls back to the non-atomic path.
kvm_s390_adapter_unmap() and kvm_s390_unmap_all_adapters() skip dirty
marking and unpin for unpinned entries.

Update Documentation/virt/kvm/devices/s390_flic.rst to reflect the
new MAP/UNMAP behavior.

Fixes: c9a5688380 ("KVM: s390: Add map/unmap ioctl and clean mappings post-guest")
Signed-off-by: Jaehoon Kim <jhkim@linux.ibm.com>
Reviewed-by: Douglas Freimuth <freimuth@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-27 09:23:53 +02:00
Linus Torvalds
86d1022b2c Merge tag 'm68knommu-fixes-on-top-off-7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
Pull m68knommu fix from Greg Ungerer:

 - fix broken local SoC IO accesses for ColdFire

* tag 'm68knommu-fixes-on-top-off-7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k: coldfire: fix breakage of missed IO access update
2026-07-26 08:59:55 -07:00
Linus Torvalds
3f97818796 Merge tag 'x86-urgent-2026-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fix from Ingo Molnar:

 - Disable jump/lookup tables in the x86 boot decompressor code
   a bit more widely, because newer versions of LLVM started
   optimizing it a bit better and introduced run-time relocations
   in PIE code (Nathan Chancellor)

* tag 'x86-urgent-2026-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/compressed: Disable jump tables
2026-07-26 08:52:38 -07:00
Linus Torvalds
3fb11702e4 Merge tag 'loongarch-fixes-7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
Pull LoongArch fixes from Huacai Chen:

 - fix build warnings and errors

 - move jump_label_init() before parse_early_param()

 - retrieve CPU package ID from PPTT when available

 - fix some bugs kgdb, BPF JIT and laptop platform driver bugs

* tag 'loongarch-fixes-7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  platform/loongarch: laptop: Explicitly reset bl_powered state when suspend
  platform/loongarch: laptop: Stop setting acpi_device_class()
  LoongArch: BPF: Fix memory leak in bpf_jit_free()
  LoongArch: BPF: Zero-extend signed ALU32 div/mod results
  LoongArch: Fix oops during single-step debugging
  LoongArch: Fix address space mismatch in kexec command line lookup
  LoongArch: Retrieve CPU package ID from PPTT when available
  LoongArch: Move jump_label_init() before parse_early_param()
  LoongArch: Fix build errors due to wrong instructions for 32BIT
  LoongArch: Increase TASK_STRUCT_OFFSET up to 2040 for 32BIT
2026-07-25 08:10:13 -07:00
Linus Torvalds
0c452fbdf4 Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
 "It's a bit all over the place, as I was hoping to fix a decade-old bug
  in our seccomp handling on syscall entry and ended up collecting other
  fixes in the meantime. You'll see the failed attempt (+revert) here
  but I didn't want to hold off on the others any longer. Hopefully
  we'll get that one squashed next week...

   - Fix early_ioremap() of unaligned ACPI tables

   - Remove bogus information from data abort diagnostics

   - Fix kprobes recursion during single-step

   - Fix incorrect constant in ESR address size fault macro

   - Fix OOB page-table walk in memory hot-unplug notifier

   - Fix OOB access to the linear map when retrieving an unaligned huge pte

   - Fix MPAM register reset values

   - Fix MPAM NULL dereference on teardown"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: make huge_ptep_get handled unaligned addresses
  arm64/mm: Check the requested PFN range during memory removal
  arm64: Correct value returned by ESR_ELx_FSC_ADDRSZ_nL()
  arm64: kprobes: Allow reentering kprobes while single-stepping
  arm64: kprobes: Only handle faults originating from XOL slot
  drivers/virt: pkvm: Fix end calculation in mmio_guard_ioremap_hook()
  Revert "arm64: syscall: Ensure saved x0 is kept in-sync with tracer updates"
  arm64: mm: When logging data aborts only decode Xs when ISV=1
  arm64: fixmap: Allow 256K early_ioremap() at any offset
  arm_mpam: guard MBWU state before adding it to garbage
  arm_mpam: Fix MPAMCFG_MBW_PBM register setting
  arm_mpam: Fix software reset values of MPAMCFG_PRI
  arm64: syscall: Ensure saved x0 is kept in-sync with tracer updates
2026-07-24 11:50:48 -07:00
Farhan Ali
868d32ac72 KVM: s390: pci: Validate AIBV and AISB before pinning guest pages
The AIBV holds one bit per MSI-X vector for a given function. The size of
the bit vector is derived from the NOI and the AIBVO. If the size of the
AIBV exceeds a single page boundary, then reject the request as we cannot
safely pin the guest AIBV.

Similarly reject the request if the AISB address is not 8-byte aligned as
the architecture requires doubleword alignment for the summary bit address.
Since the AISBO can address up to 64 bits, the size of the AISB can only be
8 bytes for the function. This also ensures the AISB doesn't exceed a
single page boundary.

Fixes: 3c5a1b6f0a ("KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding")
Cc: stable@vger.kernel.org
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-24 11:26:54 +02:00
Farhan Ali
5580c9858f KVM: s390: pci: Fix resource leak on IRQ registration failure
Currently if kvm_zpci_set_airq() fails, kvm_s390_pci_aif_enable() returns
the error code but doesn't do any resource cleanup thus leaking resources.
Fix this by cleaning up all the resources such as the GAITE, AIBV, AISB and
unpinning any pinned pages. While at it, remove dead code that stored FIB
values that were never referenced.

As part of the cleanup, we are also holding the aift_lock a bit longer, as
we hold the lock while executing the MPCIFC instruction. Though this is not
strictly necessary, it means we don't have to drop and re-acquire in the
error case.

Fixes: 3c5a1b6f0a ("KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding")
Cc: stable@vger.kernel.org
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-24 11:26:54 +02:00
Farhan Ali
8bf09b9b7d KVM: s390: pci: Fix NULL dereference on AIBV allocation failure
The airq_iv_create() can return NULL on failure, but the return value was
never checked. If it fails, zdev->aibv will be NULL and fail when
dereferenced in kvm_zpci_set_airq(). Add a NULL check and free the
previously allocated AISB bit and zdev->aisb on failure.

Fixes: 3c5a1b6f0a ("KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding")
Cc: stable@vger.kernel.org
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-24 11:26:54 +02:00
Farhan Ali
f86842e4d6 KVM: s390: pci: Fix missing error codes and memory unaccounting
In kvm_s390_pci_aif_enable() two error paths failed to set an error code,
causing the function to return 0 on failure. It also failed to rollback
memory accounting on failure. Fix both by propagating an error code on
failure and calling unaccount_mem() in the cleanup path.

Fixes: 3c5a1b6f0a ("KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding")
Cc: stable@vger.kernel.org
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-24 11:26:53 +02:00
Farhan Ali
36f6999ecd KVM: s390: pci: Fix memory accounting for pinned/unpinned pages
The account_mem() and unaccount_mem() functions call get_uid() which
increments the reference count of struct user_struct on every invocation.
But we don't decrement the count by calling free_uid(). It also
accounted/unaccounted the pages against the current->mm. But its possible
the unaccount_mem() can be called from a different process context than the
one that originally pinned the pages.

Let's fix this by storing the pinning process user_struct and mm_struct
when accounting for pinned pages, and subsequently free these resources
when the pages are unpinned.

Fixes: 3c5a1b6f0a ("KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding")
Cc: stable@vger.kernel.org
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
[borntraeger@linux.ibm.com: Fixed whitespace]
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-24 11:26:53 +02:00
Farhan Ali
8fa01be5a6 KVM: s390: pci: Reject adapter interrupt forwarding if already enabled
The MPCIFC instruction doesn't allow registering adapter interrupts without
first unregistering. So reject any request to enable interrupt forwarding
if its already enabled for the zPCI device. This also fixes overwriting and
thus leaking resources when the ioctl is called multiple times for the same
device.

Fixes: 3c5a1b6f0a ("KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding")
Cc: stable@vger.kernel.org
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-24 11:26:53 +02:00
Pu Lehui
47e20d4b3d LoongArch: BPF: Fix memory leak in bpf_jit_free()
When bpf_int_jit_compile() is called for subprograms, it returns early
during the first pass (!prog->is_func || extra_pass is false), keeping
ctx->offset alive for the subsequent extra pass.

If JIT compilation fails for a later subprogram, the BPF core aborts and
calls bpf_jit_free() to clean up the first subprogram. However,
bpf_jit_free() fails to free jit_data->ctx.offset, which causes a memory
leak of the JIT context offsets array.

So fix this by adding the missing kvfree(jit_data->ctx.offset) in
bpf_jit_free().

Reported-by: Sashiko <sashiko-bot@kernel.org>
Fixes: 4ab17e762b ("LoongArch: BPF: Use BPF prog pack allocator")
Acked-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-07-24 16:33:08 +08:00
Linus Torvalds
d326f83e81 Merge tag 'net-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
 "Lots of fixes, double the count even for the 'new normal'. Largely due
  to my time off followed by a networking conference which distracted
  most maintainers (less so the AI generators).

  Including fixes from Bluetooth and WiFi.

  Current release - regressions:

   - wifi: mt76: fix MAC address for non OF pcie cards

  Current release - new code bugs:

   - mptcp: fix BUILD_BUG_ON on legacy ARM config

   - wifi: cfg80211: guard optional PMSR nominal time

  Previous releases - regressions:

   - qrtr: ns: raise node count limit to 512, we arbitrarily picked
     256 as a limit, turns out it was too low for real world deployments

   - vhost-net: fix TX stall when vhost owns virtio-net header

   - eth: amd-xgbe: fix MAC_AUTO_SW handling in CL37 AN

   - wifi: ath12k: fix low MLO RX throughput on WCN7850

  Previous releases - always broken:

   - number of random AI fixes for SCTP, RDS and TIPC protocols

   - more AI-looking fixes for WiFi drivers

   - number of fixes for missing pointer reloading after skb pull

   - reject BPF redirect use from qdisc qevent block

   - tcp: initialize standalone TCP-AO response padding

   - vsock/virtio: collapse receive queue under memory pressure to avoid
     client OOMing the host with tiny messages

   - ipv4: icmp: fill flow parameters in icmp_route_lookup decoy lookup,
     make sure the ICMP response routing follows the routing policy

   - gro: fix double aggregation of flush-marked skbs

   - ovpn: fix various refcount bugs

   - tls: device: push pending open record on splice EOF

   - eth: mlx5:
      - use sender devcom for MPV master-up
      - fix MCIA register buffer overflow on 32 dword reads"

* tag 'net-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (234 commits)
  drop_monitor: perform u64_stats updates under IRQ-disabled section
  drop_monitor: fix size calculations for 64-bit attributes
  net: drop_monitor: fix info leak in NET_DM_ATTR_PAYLOAD
  mptcp: fix BUILD_BUG_ON on legacy ARM config
  selftests: mptcp: userspace_pm: fix undefined variable port
  mptcp: fix stale skb->sk reference on subflow close
  mptcp: pm: userspace: fix use-after-free in get_local_id
  mptcp: decrement subflows counter on failed passive join
  mac802154: hold an interface reference across the scan worker
  sctp: don't free the ASCONF's own transport in DEL-IP processing
  phonet: check register_netdevice_notifier() error in phonet_device_init()
  phonet: pep: fix use-after-free in pep_get_sb()
  bnge/bng_re: fix ring ID widths
  tipc: fix integer overflow in tipc_recvmsg() and tipc_recvstream()
  net: airoha: fix ETS channel derivation in airoha_tc_setup_qdisc_ets()
  mctp: check register_netdevice_notifier() error in mctp_device_init()
  ptp: netc: explicitly clear TMR_OFF during initialization
  rds: tcp: unregister sysctl before tearing down listen socket
  ipv6: Change allocation flags to match rcu_read_lock section requirements
  net: slip: serialize receive against buffer reallocation
  ...
2026-07-23 12:58:08 -07:00
Nicholas Dudar
dacd348b8a LoongArch: BPF: Zero-extend signed ALU32 div/mod results
ALU32 operations write a 32-bit result and leave the upper 32 bits of
the BPF register zero. The LoongArch JIT sign-extends the result of
signed ALU32 BPF_DIV and BPF_MOD (off=1), so a negative 32-bit quotient
or remainder leaves bits 63:32 set in JITted code while the verifier
and interpreter model those bits as zero.

Keep sign-extension on the operands, which signed divide needs, and
zero-extend the ALU32 result after the divide or modulo instruction,
matching the unsigned ALU32 div/mod paths and every other ALU32
operation in this JIT.

Fixes: 2425c9e002 ("LoongArch: BPF: Support signed div instructions")
Fixes: 7b6b13d329 ("LoongArch: BPF: Support signed mod instructions")
Assisted-by: Claude:claude-opus-4-8
Acked-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Nicholas Dudar <main.kalliope@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-07-23 22:27:35 +08:00
Haoran Jiang
73555fdab5 LoongArch: Fix oops during single-step debugging
When entering KDB via a breakpoint and then performing single-step
debugging, an oops is triggered. Now during single-step debugging,
kdb_local() expects the reason to be KDB_REASON_SSTEP, but it is
actually KDB_REASON_OOPS. In kdb_stub(), when determining the reason,
the ex_vector for single-step should be 0, as already implemented on
other architectures such as arm64 and riscv.

Before the patch:
[112]kdb> ss

Entering kdb (current=0x900020009f520000, pid 10661) on
processor 112 Oops: (null)
due to oops @ 0x90000000005b57a4

Cc: stable@vger.kernel.org
Signed-off-by: Haoran Jiang <jianghaoran@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-07-23 22:27:30 +08:00
George Guo
485ed44db5 LoongArch: Fix address space mismatch in kexec command line lookup
When searching the loaded segments for the "kexec" command line marker,
the kexec_load(2) path (file_mode == 0) passes the user-space segment
buffer straight to strncmp() through a bogus (char __user *) cast. This
dereferences a user pointer in kernel context, which is wrong and is
flagged by sparse:

  arch/loongarch/kernel/machine_kexec.c:84:51: sparse: incorrect type in
  argument 2 (different address spaces) @@ expected char const * @@ got
  char [noderef] __user *

Here copy the marker-sized prefix of each segment into a small on-stack
buffer with copy_from_user() before comparing, and skip segments that
fault. The subsequent copy_from_user() that stages the full command line
into the safe area is left unchanged.

Cc: stable@vger.kernel.org
Fixes: 4a03b2ac06 ("LoongArch: Add kexec support")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202605051639.aEPioXdD-lkp@intel.com/
Co-developed-by: Kexin Liu <liukexin@kylinos.cn>
Signed-off-by: Kexin Liu <liukexin@kylinos.cn>
Signed-off-by: George Guo <guodongtai@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-07-23 22:27:30 +08:00
Rong Bao
4e8f58620f LoongArch: Retrieve CPU package ID from PPTT when available
Currently, the LoongArch CPU topology initialization code calculates
each core's package ID by dividing its physical ID by loongson_sysconf.
cores_per_package. This relies on the assumption that cores_per_package
counts in the same domain as physical IDs.

On Loongson-3B6000 (XB612B0V_1.2), cores_per_package matches the visible
core count -- 24 in this case. However, the physical IDs range from 0 to
31 in a noncontinuous fashion:

        $ cat /proc/cpuinfo | grep -i -F 'global_id'
        global_id               : 0
        global_id               : 1
        global_id               : 4
        global_id               : 5
        global_id               : 6
        global_id               : 7
        global_id               : 8
        global_id               : 9
        global_id               : 10
        global_id               : 11
        global_id               : 14
        global_id               : 15
        global_id               : 16
        global_id               : 17
        global_id               : 20
        global_id               : 21
        global_id               : 22
        global_id               : 23
        global_id               : 26
        global_id               : 27
        global_id               : 28
        global_id               : 29
        global_id               : 30
        global_id               : 31

Retrieve the exact package ID from ACPI PPTT when available, in the same
style as retrieving the core ID and thread ID in parse_acpi_topology().
Use this information in loongson_init_secondary() when the PPTT readout
is successful. The original division logic is kept as a fallback.

Meanwhile, since some existing code paths like loongson3_cpufreq expect
a continuous integer sequence of package IDs in [0, MAX_PACKAGES) when
retrieving from cpu_data[], here we also canonicalize the package ID to
be filled in parse_acpi_topology() to meet such an expectation.

Cc: stable@vger.kernel.org
Tested-by: Mingcong Bai <jeffbai@aosc.io>
Co-developed-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Rong Bao <rong.bao@csmantle.top>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-07-23 22:27:29 +08:00
Kanglong Wang
ea68d444a6 LoongArch: Move jump_label_init() before parse_early_param()
When enabling both CONFIG_MEM_ALLOC_PROFILING=y and
CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT=y, then diabling memory
profiling by adding the boot parameter 'sysctl.vm.mem_profiling=0' will
cause the kernel failed to boot.

After analysis, this is because jump_label_init() must be called before
parse_early_param(), the early param handlers may modify static keys by
static_branch_enable/disable().

Fix this by moving jump_label_init() to before parse_early_param(). The
solution is similar to other architectures.

Cc: <stable@vger.kernel.org>
Signed-off-by: Kanglong Wang <wangkanglong@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-07-23 22:27:29 +08:00
Huacai Chen
7ea74820ed LoongArch: Fix build errors due to wrong instructions for 32BIT
In some assembly files there are some instructions that only valid for
64BIT, but those files can be compiled for 32BIT and cause build errors.

So, replace those instructions with macros:
li.d --> LONG_LI (li.w or li.d), addi.d --> PTR_ADDI (addi.w or addi.d).

BTW, Re-tab the indention in the assembly files for alignment.

Cc: stable@vger.kernel.org # 6.19+
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-07-23 22:27:16 +08:00
Huacai Chen
7917d16d14 LoongArch: Increase TASK_STRUCT_OFFSET up to 2040 for 32BIT
THREAD_INFO_IN_TASK increase the size of task_struct, which casuses a
build error for the 32BIT kernel if RANDSTRUCT is enabled. So increase
TASK_STRUCT_OFFSET as big as possible (2040), but can still be aligned
and be fit in the addi.w instruction.

Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-07-23 22:27:15 +08:00
Sven Schnelle
9de445d829 s390/ptff: Export ptff_function_mask[]
Export the ptff_function_mask to make ptff_query() usable in modules.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://patch.msgid.link/20260714130342.1971700-2-svens@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-23 07:02:34 -07:00
Alexandru Elisei
679d7201c1 KVM: arm64: Reject guest_memfd memslots when the VM has MTE
The user cannot use MTE on VMAs created by mapping a guest_memfd file,
as arch_calc_vm_flag_bits() does not set VM_MTE_ALLOWED.

When creating a guest_memfd backed memslot,
kvm_arch_prepare_memory_region() rejects the memslot if MTE is enabled for
the VM and if guest_memfd has been mapped in a VMA that intersects the
memslot.

However, the documentation for KVM_SET_USER_MEMORY_REGION2 explicitly
states that the only condition for userspace_addr is for it to be a legal
userspace address, but the mapping is not required to be valid nor
populated at memslot creation.

If userspace sets userspace_addr to an address that hasn't been mapped, or
if userspace_addr belongs to a VMA that isn't backed by the guest_memfd
file, or if the VMA doesn't intersect the memslot, memslot creation is
successful and KVM ends up with a VM with MTE and guest_memfd-backed
memslots.

The same happens if the order is reversed: when userspace enables MTE, KVM
does not check if memslots backed by guest_memfd are already present.

Fix both issues by rejecting guest_memfd-backed memslots when MTE is
enabled, and by rejecting MTE when guest_memfd-backed memslots are already
present.

Fixes: 32e200bd6e ("KVM: arm64: Enable support for guest_memfd backed memory")
Tested-by: Fuad Tabba <fuad.tabba@linux.dev>
Reviewed-by: Fuad Tabba <fuad.tabba@linux.dev>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://patch.msgid.link/20260722090354.94245-1-alexandru.elisei@arm.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2026-07-23 09:57:06 +01:00
Vincent Donnefort
e7821048e8 KVM: arm64: Add missing hyp_enter when trapping sysreg
Add a missing hypervisor event call for hyp_enter on sysreg trapping,
causing an unbalanced hyp_enter/hyp_exit.

The enum hyp_enter_exit_reason is not ABI, so we can keep the ERET
reasons at the end for clarity.

Fixes: 696dfec22b ("KVM: arm64: Add hyp_enter/hyp_exit events to nVHE/pKVM hyp")
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Link: https://patch.msgid.link/20260617095238.1530121-1-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2026-07-23 09:56:57 +01:00
Vincent Donnefort
ca28278d10 KVM: arm64: Fix hyp_trace_desc allocation size in hyp_trace_load()
The footprint calculated for struct hyp_trace_desc sizes only
trace_buffer_desc and do not take into account the other fields. It
worked so far thanks to the follow-up PAGE_ALIGN().

Fix the descriptor size and while at it, enforce an overflow check after
PAGE_ALIGN().

Reported-by: Sashiko <sashiko-bot@kernel.org>
Fixes: 3aed038aac ("KVM: arm64: Add trace remote for the nVHE/pKVM hyp")
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Reviewed-by: Fuad Tabba <fuad.tabba@linux.dev>
Tested-by: Fuad Tabba <fuad.tabba@linux.dev>
Link: https://patch.msgid.link/20260710114819.2689386-3-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2026-07-23 09:56:57 +01:00
Vincent Donnefort
df7a9d376f KVM: arm64: Fix potential leak in hyp_trace_buffer_alloc_bpages_backing
In the very unlikely event of a failure in __map_hyp, the allocated
backing pages are leaked in hyp_trace_buffer_alloc_bpages_backing(). Fix
this by freeing the pages on error.

Fixes: 3aed038aac ("KVM: arm64: Add trace remote for the nVHE/pKVM hyp")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Reviewed-by: Fuad Tabba <fuad.tabba@linux.dev>
Tested-by: Fuad Tabba <fuad.tabba@linux.dev>
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Link: https://patch.msgid.link/20260710114819.2689386-2-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2026-07-23 09:56:57 +01:00
Vincent Donnefort
bbece712cf KVM: arm64: Fix hyp_trace clock disabling
Fix the disable path in hyp_trace_clock_enable(), which fell through to
re-initialize and reschedule the clock after cancelling the work. Return
early instead.

While at it, cleanup hyp_trace_clock::lock which is unused and
hyp_trace_clock::running which is redundant: the trace_remote framework
already serializes calls to the callback enable_tracing.

Fixes: b22888917f ("KVM: arm64: Sync boot clock with the nVHE/pKVM hyp")
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Reviewed-by: Fuad Tabba <fuad.tabba@linux.dev> (✓ DKIM/linux.dev)
Link: https://patch.msgid.link/20260715105100.3178255-1-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2026-07-23 09:56:57 +01:00
Carlos López
21f12496fd KVM: arm64: vgic: Mitigate potential LPI registration failure
Mitigate a potential failure when inserting a new LPI into the VGIC LPI
xarray.

When vgic_add_lpi() is preparing to register a new LPI, it pre-allocates
an xarray entry using xa_reserve_irq(), so that it can later perform the
insertion under the xarray lock without allocating.

However, since xa_reserve_irq() is called before acquiring such lock,
there is a potential race where xa_reserve_irq() observes a populated
entry, thus not performing the allocation, and another CPU removes that
entry before the xarray lock is grabbed to perform the insertion.

  CPU0 (Adding new LPI)                      CPU1 (Releasing LPI)
  =====================                      ===================
  vgic_add_lpi()
      /* Entry populated, does not allocate */
      xa_reserve_irq(.., intid, ..)
                                            vgic_release_deleted_lpis()
                                                xa_lock_irqsave()
                                                vgic_release_lpi_locked()
                          xarray node freed --> __xa_erase(.., intid)
                                                xa_unlock_irqrestore()
      xa_lock_irqsave()
      xa_load(.., intid) == NULL
      vgic_try_get_irq_ref(NULL) == false
      __xa_store(.., intid, irq, 0) <-- xarray node was freed, gfp=0
                                        cannot allocate, returns -ENOMEM

This can happen e.g. if the guest issues a DISCARD while the LPI is
still referenced from a vCPU's active-pending list (ap_list), and the
same INTID is re-mapped via MAPTI.

Mitigate this by passing GFP_NOWAIT to __xa_store(), so that the
allocation can happen under the lock in the rare case that this
condition is hit. Add __GFP_ACCOUNT as well to match xa_reserve_irq()'s
flags.

Reported-by: Sashiko <sashiko-bot@kernel.org>
Fixes: 1d6f83f60f ("KVM: arm64: vgic: Store LPIs in an xarray")
Signed-off-by: Carlos López <clopez@suse.de>
Link: https://patch.msgid.link/20260715105137.3973823-5-clopez@suse.de
Signed-off-by: Marc Zyngier <maz@kernel.org>
2026-07-23 09:56:57 +01:00
Carlos López
cbfe2b24a1 KVM: arm64: vgic: Fix race between LPI release and re-registration
Fix a potential race between decrementing an LPI's reference count and
evicting that structure from the LPI xarray.

LPI structures are maintained in the VGIC LPI xarray (dist->lpi_xa).
When the reference count of an LPI structure drops to zero,
vgic_release_lpi_locked() removes the structure from the xarray and
frees it under the xarray lock.

However, the release of an LPI can race with a concurrent LPI
re-registration with the same INTID via vgic_add_lpi() on another CPU,
since the reference count drop and the xarray eviction are not performed
in a single atomic step. This can happen e.g. if the guest issues a
DISCARD while the LPI is still referenced from a vCPU's active-pending
list (ap_list), and the same INTID is re-mapped via MAPTI.

Particularly, vgic_release_lpi_locked() is called from two distinct
paths: direct release via vgic_put_irq(), and deferred release via
vgic_release_deleted_lpis(). During direct release, the issue can result
in deleting a newly registered LPI from the xarray:

  CPU0 (Releasing LPI)                    CPU1 (Adding new LPI)
  ====================                    =====================
  vgic_put_irq()
      __vgic_put_irq()
          refcount_dec_and_test()
                                          vgic_add_lpi()
                                              xa_lock_irqsave()
                                              old_irq = xa_load(.., intid)
                                              vgic_try_get_irq_ref(old_irq) == false
                        new IRQ inserted -->  __xa_store(.., intid, ..)
                                              xa_unlock_irqrestore()
  xa_lock_irqsave();
  vgic_release_lpi_locked()
      __xa_erase(.., irq->intid)   <-- BUG: new IRQ is erased
      kfree_rcu(old_irq)

During the deferred release path, the old IRQ can be leaked:

  CPU0 (Releasing LPI)                    CPU1 (Adding new LPI)
  ====================                    =====================
  vgic_put_irq_norelease()
      __vgic_put_irq()
          refcount_dec_and_test()
      irq->pending_release = true
                                          vgic_add_lpi()
                                              xa_lock_irqsave()
                                              old_irq = xa_load(.., intid)
                                              vgic_try_get_irq_ref(oldirq) == false
                 BUG: old IRQ overwritten --> __xa_store(.., intid, ..)
                                              xa_unlock_irqrestore()

  vgic_release_deleted_lpis()
      xa_lock_irqsave()
      xa_for_each() { .. } <-- old IRQ with pending_release = true
                               is gone, so it cannot be released

To fix the direct release path, move the reference count drop inside
the xarray lock, making sure that vgic_add_lpi() never encounters the
to-be-released LPI.

In the deferred release path, the refcount drop must happen under a raw
spinlock, so the xarray lock cannot be grabbed, and the same solution
does not work. Instead, update vgic_add_lpi(), so that if it evicts
an LPI from the xarray, it takes on the responsibility of freeing it.
Consequently, an LPI may now be freed concurrently after a deferred
release drops the refcount, so accessing the pending_release field is no
longer safe from use-after-free. Delete all uses of the flag, and update
vgic_release_deleted_lpis() to identify orphaned LPIs purely based on
their refcount.

Reported-by: Claude:claude-opus-4-6
Fixes: 3a08a6ca7c ("KVM: arm64: vgic-v3: Use bare refcount for VGIC LPIs")
Fixes: d54594accf ("KVM: arm64: vgic-v3: Erase LPIs from xarray outside of raw spinlocks")
Signed-off-by: Carlos López <clopez@suse.de>
Link: https://patch.msgid.link/20260715105137.3973823-4-clopez@suse.de
Signed-off-by: Marc Zyngier <maz@kernel.org>
2026-07-23 09:56:57 +01:00
Nathan Chancellor
4a9ec5ec95 x86/boot/compressed: Disable jump tables
After a recent upstream LLVM change to start generating jump and lookup
tables in switch statements in more instances [1], linking the
compressed x86 boot image when CONFIG_KERNEL_ZSTD is enabled fails with:

  ld.lld: error: Unexpected run-time relocations (.rela) detected!

Dumping the relocations in misc.o, which is the only file influenced by
CONFIG_KERNEL_ZSTD in the decompressor, shows dynamic relocations to
some string constants, which correspond to the string literals in the
switch statement in handle_zstd_error():

  Relocation section '.rela.data.rel.ro' at offset 0x277b0 contains 31 entries:
      Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
  0000000000000000  0000006600000001 R_X86_64_64            0000000000000000 .rodata.str1.1 + 73a
  0000000000000008  0000006600000001 R_X86_64_64            0000000000000000 .rodata.str1.1 + 78e
  0000000000000010  0000006600000001 R_X86_64_64            0000000000000000 .rodata.str1.1 + 78e
  0000000000000018  0000006600000001 R_X86_64_64            0000000000000000 .rodata.str1.1 + 78e
  ...

This optimization is problematic for the decompressor environment, as it
is built as -fPIE without any explicit absolute references (as described
at the top of misc.c) while not applying any dynamic relocations, hence
the linker assertion. To opt out of this optimization, which is of
little value in this special early boot code, and to mirror the other
x86 startup code in arch/x86/boot/startup, disable jump tables in the
decompressor.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Bill Wendling <morbo@google.com>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: fa02a6ed66 [1]
Link: https://patch.msgid.link/20260722-x86-boot-compressed-disable-jt-clang-v2-1-7373d38482fb@kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/2165
2026-07-23 10:06:58 +02:00
Dev Jain
f73a8edc2c arm64: make huge_ptep_get handled unaligned addresses
huge_ptep_get() can be handed a virtual address pointing to the middle
of a contpmd/contpte mapped hugetlb folio (examples of callers are
pagemap_hugetlb_range, page_mapped_in_vma).

The arm64 helper rewalks the pgtables in find_num_contig to answer
whether the huge pte we have maps a contpmd or a contpte hugetlb folio,
and returns CONT_PMDS or CONT_PTES, so that it can collect a/d bits over
the contiguous ptes. We can falsely return CONT_PTES instead of
CONT_PMDS if the addr is not aligned. On systems where CONT_PTES !=
CONT_PMDS (meaning page size is 16K), we could collect excess A/D bit
state, meaning extra work for the kernel. Even worse, we may iterate
beyond the PTE table and dereference a garbage ptep pointer to access
physical memory we don't own. Since the ptep pointer is a linear map
address, we may run off the end of the linear map or into a hole,
dereference a VA not mapped into the kernel pgtables and cause kernel
panic.

Fix this by aligning the pmdp pointer down to a contpmd base before
checking equality with the passed huge pte pointer, to correctly answer
whether the huge pte is the base of a contpmd block.

Fixes: 29cb805196 ("arm64: hugetlb: Cleanup huge_pte size discovery mechanisms")
Cc: stable@vger.kernel.org
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Dev Jain <dev.jain@arm.com>
Acked-by: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Will Deacon <will@kernel.org>
2026-07-22 11:44:47 +00:00
Linus Torvalds
b4b760b59f Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
 "RISC-V:

   - Avoid redundant allocations when allocating IMSIC page tables

   - Apply SBI FWFT LOCK flag only on successful set

   - Bound SBI PMU counter mask scan to BITS_PER_LONG, since on RV32 the
     PMU SBI start/stop helper can only access 32 PMU counters.

   - Skip TLB flush when G-stage PTE becomes valid if the Svvptc
     extension is available.

   - Always show Zicbo[m|z|p] block sizes in ONE_REG

   - Inject instruction access fault on unmapped guest fetch

   - Use raw spinlock for irqs_pending and irqs_pending_mask

   - Fix Spectre-v1 in vector register access via ONE_REG

  x86:

   - Fixes to SEV selftests

   - Once free_nested() did a VMCLEAR of shadow VMCS, there's no need to
     VMCLEAR it again if the kernel is preempted and thread migration
     happens

   - Preserve nested TDP shadow page tables if they are used as roots,
     instead of clearing them unnecessarily

   - Fix use of stale data if out-of-memory happens after vendor module
     reload

   - Check for invalid/obsolete root *after* making MMU pages available,
     because the latter can make a page invalid

   - Only reset TSC Deadline Timer in apic_timer_expired on KVM_RUN"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: Only reset TSC Deadline Timer in apic_timer_expired on KVM_RUN
  KVM: selftests: sev_init2_tests: Derive SEV availability from KVM
  KVM: selftests: sev_smoke_test: Only run VM types the host offers
  KVM: x86/mmu: Fix use-after-free on vendor module reload
  KVM: x86/mmu: Preserve nested TDP shadow page tables if they are used as roots
  KVM: x86: Check for invalid/obsolete root *after* making MMU pages available
  KVM: nVMX: Hide shadow VMCS right after VMCLEAR
  KVM: riscv: Fix Spectre-v1 in vector register access
  RISC-V: KVM: Serialize virtual interrupt pending state updates
  RISC-V: KVM: Inject instruction access fault on unmapped guest fetch
  RISC-V: KVM: Zicbo[m|z|p] block sizes should be always present in ONE_REG
  riscv: kvm: Skip TLB flush when G-stage PTE becomes valid with Svvptc
  KVM: riscv: PMU: Bound counter mask scan to BITS_PER_LONG
  KVM: riscv: SBI FWFT: Apply LOCK flag only on successful set
  RISC-V: KVM: Avoid redundant page-table allocations in ioremap topup
2026-07-21 08:26:21 -07:00