Commit Graph

229909 Commits

Author SHA1 Message Date
Bibo Mao
d8cc4fee3f LoongArch: KVM: Remove duplicated cache attribute setting
Cache attribute comes from GPA->HPA secondary mmu page table and is
configured when kvm is enabled. It is the same for all VMs, so remove
duplicated cache attribute setting on vCPU context switch.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-02-13 12:02:56 +08:00
Bibo Mao
bdb13252e5 LoongArch: KVM: Fix typo issue about GCFG feature detection
This is typo issue and misusage about GCFG feature macro. The code
is wrong, only that it does not cause obvious problem since GCFG is
set again on vCPU context switch.

Fixes: 0d0df3c99d ("LoongArch: KVM: Implement kvm hardware enable, disable interface")
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-02-13 12:02:56 +08:00
Yuli Wang
6287f1a8c1 LoongArch: csum: Fix OoB access in IP checksum code for negative lengths
Commit 69e3a6aa6b ("LoongArch: Add checksum optimization for 64-bit
system") would cause an undefined shift and an out-of-bounds read.

Commit 8bd795fedb ("arm64: csum: Fix OoB access in IP checksum code
for negative lengths") fixes the same issue on ARM64.

Fixes: 69e3a6aa6b ("LoongArch: Add checksum optimization for 64-bit system")
Co-developed-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Yuli Wang <wangyuli@uniontech.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-02-13 12:02:40 +08:00
Yuli Wang
6b72cd9ef0 LoongArch: Remove the deprecated notifier hook mechanism
The notifier hook mechanism in proc and cpuinfo is actually unnecessary
for LoongArch because it's not used anywhere.

It was originally added to the MIPS code in commit d6d3c9afaa ("MIPS:
MT: proc: Add support for printing VPE and TC ids"), and LoongArch then
inherited it.

But as the kernel code stands now, this notifier hook mechanism doesn't
really make sense for either LoongArch or MIPS.

In addition, the seq_file forward declaration needs to be moved to its
proper place, as only the show_ipi_list() function in smp.c requires it.

Co-developed-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Yuli Wang <wangyuli@uniontech.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-02-13 12:02:40 +08:00
Yuli Wang
03a99d16e6 LoongArch: Use str_yes_no() helper function for /proc/cpuinfo
Remove hard-coded strings by using the str_yes_no() helper function.

Similar to commit c4a0a4a45a ("MIPS: kernel: proc: Use str_yes_no()
helper function").

Co-developed-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Yuli Wang <wangyuli@uniontech.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-02-13 12:02:35 +08:00
Huacai Chen
619b52777a LoongArch: Fix kernel_page_present() for KPRANGE/XKPRANGE
Now kernel_page_present() always return true for KPRANGE/XKPRANGE
addresses, this isn't correct because hibernation (ACPI S4) use it
to distinguish whether a page is saveable. If all KPRANGE/XKPRANGE
addresses are considered as saveable, then reserved memory such as
EFI_RUNTIME_SERVICES_CODE / EFI_RUNTIME_SERVICES_DATA will also be
saved and restored.

Fix this by returning true only if the KPRANGE/XKPRANGE address is in
memblock.memory.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-02-13 12:02:35 +08:00
Marco Crivellari
edb1942542 LoongArch: Fix idle VS timer enqueue
LoongArch re-enables interrupts on its idle routine and performs a
TIF_NEED_RESCHED check afterwards before putting the CPU to sleep.

The IRQs firing between the check and the idle instruction may set the
TIF_NEED_RESCHED flag. In order to deal with such a race, IRQs
interrupting __arch_cpu_idle() rollback their return address to the
beginning of __arch_cpu_idle() so that TIF_NEED_RESCHED is checked
again before going back to sleep.

However idle IRQs can also queue timers that may require a tick
reprogramming through a new generic idle loop iteration but those timers
would go unnoticed here because __arch_cpu_idle() only checks
TIF_NEED_RESCHED. It doesn't check for pending timers.

Fix this with fast-forwarding idle IRQs return address to the end of the
idle routine instead of the beginning, so that the generic idle loop can
handle both TIF_NEED_RESCHED and pending timers.

Fixes: 0603839b18 ("LoongArch: Add exception/interrupt handling")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-02-13 12:02:35 +08:00
Johannes Berg
96178631c3 um: convert irq_lock to raw spinlock
Since this is deep in the architecture, and the code is
called nested into other deep management code, this really
needs to be a raw spinlock. Convert it.

Link: https://patch.msgid.link/20250110125550.32479-8-johannes@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2025-02-12 23:40:59 +01:00
Johannes Berg
daa1a05ba4 um: virtio_uml: use raw spinlock
This is needed because at least in time-travel the code
can be called directly from the deep architecture and
IRQ handling code.

Link: https://patch.msgid.link/20250110125550.32479-7-johannes@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2025-02-12 23:40:55 +01:00
Johannes Berg
5b166b782d um: virt-pci: don't use kmalloc()
This code can be called deep in the IRQ handling, for
example, and then cannot normally use kmalloc(). Have
its own pre-allocated memory and use from there instead
so this doesn't occur. Only in the (very rare) case of
memcpy_toio() we'd still need to allocate memory.

Link: https://patch.msgid.link/20250110125550.32479-6-johannes@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2025-02-12 23:40:50 +01:00
Benjamin Berg
f82a9e7b9f um: fix execve stub execution on old host OSs
The stub execution uses the somewhat new close_range and execveat
syscalls. Of these two, the execveat call is essential, but the
close_range call is more about stub process hygiene rather than safety
(and its result is ignored).

Replace both calls with a raw syscall as older machines might not have a
recent enough kernel for close_range (with CLOSE_RANGE_CLOEXEC) or a
libc that does not yet expose both of the syscalls.

Fixes: 32e8eaf263 ("um: use execveat to create userspace MMs")
Reported-by: Glenn Washburn <development@efficientek.com>
Closes: https://lore.kernel.org/20250108022404.05e0de1e@crass-HP-ZBook-15-G2
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20250113094107.674738-1-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2025-02-12 23:40:45 +01:00
Benjamin Berg
3c2fc7434d um: properly align signal stack on x86_64
The stack needs to be properly aligned so 16 byte memory accesses on the
stack are correct. This was broken when introducing the dynamic math
register sizing as the rounding was not moved appropriately.

Fixes: 3f17fed214 ("um: switch to regset API and depend on XSTATE")
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20250107133509.265576-1-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2025-02-12 23:40:42 +01:00
Benjamin Berg
8891b176d3 um: avoid copying FP state from init_task
The init_task instance of struct task_struct is statically allocated and
does not contain the dynamic area for the userspace FP registers. As
such, limit the copy to the valid area of init_task and fill the rest
with zero.

Note that the FP state is only needed for userspace, and as such it is
entirely reasonable for init_task to not contain it.

Reported-by: Brian Norris <briannorris@chromium.org>
Closes: https://lore.kernel.org/Z1ySXmjZm-xOqk90@google.com
Fixes: 3f17fed214 ("um: switch to regset API and depend on XSTATE")
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20241217202745.1402932-3-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2025-02-12 23:40:38 +01:00
Benjamin Berg
5298b7cffa um: add back support for FXSAVE registers
It was reported that qemu may not enable the XSTATE CPU extension, which
is a requirement after commit 3f17fed214 ("um: switch to regset API
and depend on XSTATE"). Add a fallback to use FXSAVE (FP registers on
x86_64 and XFP on i386) which is just a shorter version of the same
data. The only difference is that the XSTATE magic should not be set in
the signal frame.

Note that this still drops support for the older i386 FP register layout
as supporting this would require more backward compatibility to build a
correct signal frame.

Fixes: 3f17fed214 ("um: switch to regset API and depend on XSTATE")
Reported-by: SeongJae Park <sj@kernel.org>
Closes: https://lore.kernel.org/r/20241203070218.240797-1-sj@kernel.org
Tested-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20241204074827.1582917-1-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2025-02-12 23:40:10 +01:00
Sean Christopherson
c2fee09fc1 KVM: x86: Load DR6 with guest value only before entering .vcpu_run() loop
Move the conditional loading of hardware DR6 with the guest's DR6 value
out of the core .vcpu_run() loop to fix a bug where KVM can load hardware
with a stale vcpu->arch.dr6.

When the guest accesses a DR and host userspace isn't debugging the guest,
KVM disables DR interception and loads the guest's values into hardware on
VM-Enter and saves them on VM-Exit.  This allows the guest to access DRs
at will, e.g. so that a sequence of DR accesses to configure a breakpoint
only generates one VM-Exit.

For DR0-DR3, the logic/behavior is identical between VMX and SVM, and also
identical between KVM_DEBUGREG_BP_ENABLED (userspace debugging the guest)
and KVM_DEBUGREG_WONT_EXIT (guest using DRs), and so KVM handles loading
DR0-DR3 in common code, _outside_ of the core kvm_x86_ops.vcpu_run() loop.

But for DR6, the guest's value doesn't need to be loaded into hardware for
KVM_DEBUGREG_BP_ENABLED, and SVM provides a dedicated VMCB field whereas
VMX requires software to manually load the guest value, and so loading the
guest's value into DR6 is handled by {svm,vmx}_vcpu_run(), i.e. is done
_inside_ the core run loop.

Unfortunately, saving the guest values on VM-Exit is initiated by common
x86, again outside of the core run loop.  If the guest modifies DR6 (in
hardware, when DR interception is disabled), and then the next VM-Exit is
a fastpath VM-Exit, KVM will reload hardware DR6 with vcpu->arch.dr6 and
clobber the guest's actual value.

The bug shows up primarily with nested VMX because KVM handles the VMX
preemption timer in the fastpath, and the window between hardware DR6
being modified (in guest context) and DR6 being read by guest software is
orders of magnitude larger in a nested setup.  E.g. in non-nested, the
VMX preemption timer would need to fire precisely between #DB injection
and the #DB handler's read of DR6, whereas with a KVM-on-KVM setup, the
window where hardware DR6 is "dirty" extends all the way from L1 writing
DR6 to VMRESUME (in L1).

    L1's view:
    ==========
    <L1 disables DR interception>
           CPU 0/KVM-7289    [023] d....  2925.640961: kvm_entry: vcpu 0
 A:  L1 Writes DR6
           CPU 0/KVM-7289    [023] d....  2925.640963: <hack>: Set DRs, DR6 = 0xffff0ff1

 B:        CPU 0/KVM-7289    [023] d....  2925.640967: kvm_exit: vcpu 0 reason EXTERNAL_INTERRUPT intr_info 0x800000ec

 D: L1 reads DR6, arch.dr6 = 0
           CPU 0/KVM-7289    [023] d....  2925.640969: <hack>: Sync DRs, DR6 = 0xffff0ff0

           CPU 0/KVM-7289    [023] d....  2925.640976: kvm_entry: vcpu 0
    L2 reads DR6, L1 disables DR interception
           CPU 0/KVM-7289    [023] d....  2925.640980: kvm_exit: vcpu 0 reason DR_ACCESS info1 0x0000000000000216
           CPU 0/KVM-7289    [023] d....  2925.640983: kvm_entry: vcpu 0

           CPU 0/KVM-7289    [023] d....  2925.640983: <hack>: Set DRs, DR6 = 0xffff0ff0

    L2 detects failure
           CPU 0/KVM-7289    [023] d....  2925.640987: kvm_exit: vcpu 0 reason HLT
    L1 reads DR6 (confirms failure)
           CPU 0/KVM-7289    [023] d....  2925.640990: <hack>: Sync DRs, DR6 = 0xffff0ff0

    L0's view:
    ==========
    L2 reads DR6, arch.dr6 = 0
          CPU 23/KVM-5046    [001] d....  3410.005610: kvm_exit: vcpu 23 reason DR_ACCESS info1 0x0000000000000216
          CPU 23/KVM-5046    [001] .....  3410.005610: kvm_nested_vmexit: vcpu 23 reason DR_ACCESS info1 0x0000000000000216

    L2 => L1 nested VM-Exit
          CPU 23/KVM-5046    [001] .....  3410.005610: kvm_nested_vmexit_inject: reason: DR_ACCESS ext_inf1: 0x0000000000000216

          CPU 23/KVM-5046    [001] d....  3410.005610: kvm_entry: vcpu 23
          CPU 23/KVM-5046    [001] d....  3410.005611: kvm_exit: vcpu 23 reason VMREAD
          CPU 23/KVM-5046    [001] d....  3410.005611: kvm_entry: vcpu 23
          CPU 23/KVM-5046    [001] d....  3410.005612: kvm_exit: vcpu 23 reason VMREAD
          CPU 23/KVM-5046    [001] d....  3410.005612: kvm_entry: vcpu 23

    L1 writes DR7, L0 disables DR interception
          CPU 23/KVM-5046    [001] d....  3410.005612: kvm_exit: vcpu 23 reason DR_ACCESS info1 0x0000000000000007
          CPU 23/KVM-5046    [001] d....  3410.005613: kvm_entry: vcpu 23

    L0 writes DR6 = 0 (arch.dr6)
          CPU 23/KVM-5046    [001] d....  3410.005613: <hack>: Set DRs, DR6 = 0xffff0ff0

 A: <L1 writes DR6 = 1, no interception, arch.dr6 is still '0'>

 B:       CPU 23/KVM-5046    [001] d....  3410.005614: kvm_exit: vcpu 23 reason PREEMPTION_TIMER
          CPU 23/KVM-5046    [001] d....  3410.005614: kvm_entry: vcpu 23

 C: L0 writes DR6 = 0 (arch.dr6)
          CPU 23/KVM-5046    [001] d....  3410.005614: <hack>: Set DRs, DR6 = 0xffff0ff0

    L1 => L2 nested VM-Enter
          CPU 23/KVM-5046    [001] d....  3410.005616: kvm_exit: vcpu 23 reason VMRESUME

    L0 reads DR6, arch.dr6 = 0

Reported-by: John Stultz <jstultz@google.com>
Closes: https://lkml.kernel.org/r/CANDhNCq5_F3HfFYABqFGCA1bPd_%2BxgNj-iDQhH4tDk%2Bwi8iZZg%40mail.gmail.com
Fixes: 375e28ffc0 ("KVM: X86: Set host DR6 only on VMX and for KVM_DEBUGREG_WONT_EXIT")
Fixes: d67668e9dd ("KVM: x86, SVM: isolate vcpu->arch.dr6 from vmcb->save.dr6")
Cc: stable@vger.kernel.org
Cc: Jim Mattson <jmattson@google.com>
Tested-by: John Stultz <jstultz@google.com>
Link: https://lore.kernel.org/r/20250125011833.3644371-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-12 08:59:38 -08:00
Sean Christopherson
46d6c6f3ef KVM: nSVM: Enter guest mode before initializing nested NPT MMU
When preparing vmcb02 for nested VMRUN (or state restore), "enter" guest
mode prior to initializing the MMU for nested NPT so that guest_mode is
set in the MMU's role.  KVM's model is that all L2 MMUs are tagged with
guest_mode, as the behavior of hypervisor MMUs tends to be significantly
different than kernel MMUs.

Practically speaking, the bug is relatively benign, as KVM only directly
queries role.guest_mode in kvm_mmu_free_guest_mode_roots() and
kvm_mmu_page_ad_need_write_protect(), which SVM doesn't use, and in paths
that are optimizations (mmu_page_zap_pte() and
shadow_mmu_try_split_huge_pages()).

And while the role is incorprated into shadow page usage, because nested
NPT requires KVM to be using NPT for L1, reusing shadow pages across L1
and L2 is impossible as L1 MMUs will always have direct=1, while L2 MMUs
will have direct=0.

Hoist the TLB processing and setting of HF_GUEST_MASK to the beginning
of the flow instead of forcing guest_mode in the MMU, as nothing in
nested_vmcb02_prepare_control() between the old and new locations touches
TLB flush requests or HF_GUEST_MASK, i.e. there's no reason to present
inconsistent vCPU state to the MMU.

Fixes: 69cb877487 ("KVM: nSVM: move MMU setup to nested_prepare_vmcb_control")
Cc: stable@vger.kernel.org
Reported-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Reviewed-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Link: https://lore.kernel.org/r/20250130010825.220346-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-12 08:57:55 -08:00
Sean Christopherson
a8de7f100b KVM: x86: Reject Hyper-V's SEND_IPI hypercalls if local APIC isn't in-kernel
Advertise support for Hyper-V's SEND_IPI and SEND_IPI_EX hypercalls if and
only if the local API is emulated/virtualized by KVM, and explicitly reject
said hypercalls if the local APIC is emulated in userspace, i.e. don't rely
on userspace to opt-in to KVM_CAP_HYPERV_ENFORCE_CPUID.

Rejecting SEND_IPI and SEND_IPI_EX fixes a NULL-pointer dereference if
Hyper-V enlightenments are exposed to the guest without an in-kernel local
APIC:

  dump_stack+0xbe/0xfd
  __kasan_report.cold+0x34/0x84
  kasan_report+0x3a/0x50
  __apic_accept_irq+0x3a/0x5c0
  kvm_hv_send_ipi.isra.0+0x34e/0x820
  kvm_hv_hypercall+0x8d9/0x9d0
  kvm_emulate_hypercall+0x506/0x7e0
  __vmx_handle_exit+0x283/0xb60
  vmx_handle_exit+0x1d/0xd0
  vcpu_enter_guest+0x16b0/0x24c0
  vcpu_run+0xc0/0x550
  kvm_arch_vcpu_ioctl_run+0x170/0x6d0
  kvm_vcpu_ioctl+0x413/0xb20
  __se_sys_ioctl+0x111/0x160
  do_syscal1_64+0x30/0x40
  entry_SYSCALL_64_after_hwframe+0x67/0xd1

Note, checking the sending vCPU is sufficient, as the per-VM irqchip_mode
can't be modified after vCPUs are created, i.e. if one vCPU has an
in-kernel local APIC, then all vCPUs have an in-kernel local APIC.

Reported-by: Dongjie Zou <zoudongjie@huawei.com>
Fixes: 214ff83d44 ("KVM: x86: hyperv: implement PV IPI send hypercalls")
Fixes: 2bc39970e9 ("x86/kvm/hyper-v: Introduce KVM_GET_SUPPORTED_HV_CPUID")
Cc: stable@vger.kernel.org
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20250118003454.2619573-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-12 08:53:56 -08:00
Christophe Leroy
d262a192d3 powerpc/code-patching: Fix KASAN hit by not flagging text patching area as VM_ALLOC
Erhard reported the following KASAN hit while booting his PowerMac G4
with a KASAN-enabled kernel 6.13-rc6:

  BUG: KASAN: vmalloc-out-of-bounds in copy_to_kernel_nofault+0xd8/0x1c8
  Write of size 8 at addr f1000000 by task chronyd/1293

  CPU: 0 UID: 123 PID: 1293 Comm: chronyd Tainted: G        W          6.13.0-rc6-PMacG4 #2
  Tainted: [W]=WARN
  Hardware name: PowerMac3,6 7455 0x80010303 PowerMac
  Call Trace:
  [c2437590] [c1631a84] dump_stack_lvl+0x70/0x8c (unreliable)
  [c24375b0] [c0504998] print_report+0xdc/0x504
  [c2437610] [c050475c] kasan_report+0xf8/0x108
  [c2437690] [c0505a3c] kasan_check_range+0x24/0x18c
  [c24376a0] [c03fb5e4] copy_to_kernel_nofault+0xd8/0x1c8
  [c24376c0] [c004c014] patch_instructions+0x15c/0x16c
  [c2437710] [c00731a8] bpf_arch_text_copy+0x60/0x7c
  [c2437730] [c0281168] bpf_jit_binary_pack_finalize+0x50/0xac
  [c2437750] [c0073cf4] bpf_int_jit_compile+0xb30/0xdec
  [c2437880] [c0280394] bpf_prog_select_runtime+0x15c/0x478
  [c24378d0] [c1263428] bpf_prepare_filter+0xbf8/0xc14
  [c2437990] [c12677ec] bpf_prog_create_from_user+0x258/0x2b4
  [c24379d0] [c027111c] do_seccomp+0x3dc/0x1890
  [c2437ac0] [c001d8e0] system_call_exception+0x2dc/0x420
  [c2437f30] [c00281ac] ret_from_syscall+0x0/0x2c
  --- interrupt: c00 at 0x5a1274
  NIP:  005a1274 LR: 006a3b3c CTR: 005296c8
  REGS: c2437f40 TRAP: 0c00   Tainted: G        W           (6.13.0-rc6-PMacG4)
  MSR:  0200f932 <VEC,EE,PR,FP,ME,IR,DR,RI>  CR: 24004422  XER: 00000000

  GPR00: 00000166 af8f3fa0 a7ee3540 00000001 00000000 013b6500 005a5858 0200f932
  GPR08: 00000000 00001fe9 013d5fc8 005296c8 2822244c 00b2fcd8 00000000 af8f4b57
  GPR16: 00000000 00000001 00000000 00000000 00000000 00000001 00000000 00000002
  GPR24: 00afdbb0 00000000 00000000 00000000 006e0004 013ce060 006e7c1c 00000001
  NIP [005a1274] 0x5a1274
  LR [006a3b3c] 0x6a3b3c
  --- interrupt: c00

  The buggy address belongs to the virtual mapping at
   [f1000000, f1002000) created by:
   text_area_cpu_up+0x20/0x190

  The buggy address belongs to the physical page:
  page: refcount:1 mapcount:0 mapping:00000000 index:0x0 pfn:0x76e30
  flags: 0x80000000(zone=2)
  raw: 80000000 00000000 00000122 00000000 00000000 00000000 ffffffff 00000001
  raw: 00000000
  page dumped because: kasan: bad access detected

  Memory state around the buggy address:
   f0ffff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
   f0ffff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  >f1000000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
             ^
   f1000080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
   f1000100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
  ==================================================================

f8 corresponds to KASAN_VMALLOC_INVALID which means the area is not
initialised hence not supposed to be used yet.

Powerpc text patching infrastructure allocates a virtual memory area
using get_vm_area() and flags it as VM_ALLOC. But that flag is meant
to be used for vmalloc() and vmalloc() allocated memory is not
supposed to be used before a call to __vmalloc_node_range() which is
never called for that area.

That went undetected until commit e4137f0881 ("mm, kasan, kmsan:
instrument copy_from/to_kernel_nofault")

The area allocated by text_area_cpu_up() is not vmalloc memory, it is
mapped directly on demand when needed by map_kernel_page(). There is
no VM flag corresponding to such usage, so just pass no flag. That way
the area will be unpoisonned and usable immediately.

Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Closes: https://lore.kernel.org/all/20250112135832.57c92322@yea/
Fixes: 37bc3e5fd7 ("powerpc/lib/code-patching: Use alternate map for patch_instruction()")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/06621423da339b374f48c0886e3a5db18e896be8.1739342693.git.christophe.leroy@csgroup.eu
2025-02-12 14:38:13 +05:30
Patrick Wildt
8546cfd08a arm64: dts: rockchip: adjust SMMU interrupt type on rk3588
The SMMU architecture requires wired interrupts to be edge triggered,
which does not align with the DT description for the RK3588.  This leads
to interrupt storms, as the SMMU continues to hold the pin high and only
pulls it down for a short amount when issuing an IRQ.  Update the DT
description to be in line with the spec and perceived reality.

Signed-off-by: Patrick Wildt <patrick@blueri.se>
Fixes: cd81d3a069 ("arm64: dts: rockchip: add rk3588 pcie and php IOMMUs")
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Link: https://lore.kernel.org/r/Z6pxme2Chmf3d3uK@windev.fritz.box
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2025-02-11 21:28:13 +01:00
Niklas Cassel
7d1163fc08 arm64: dts: rockchip: disable IOMMU when running rk3588 in PCIe endpoint mode
Commit da92d3dfc8 ("arm64: dts: rockchip: enable the mmu600_pcie IOMMU
on the rk3588 SoC") enabled the mmu600_pcie IOMMU, both in the normal case
(when all PCIe controllers are running in Root Complex mode) and in the
case when running the pcie3x4 PCIe controller in Endpoint mode.

There have been no issues detected when running the PCIe controllers in
Root Complex mode. During PCI probe time, we will add a SID to the IOMMU
for each PCI device enumerated on the bus, including the root port itself.

However, when running the pcie3x4 PCIe controller in Endpoint mode, we
will only add a single SID to the IOMMU (the SID specified in the iommus
DT property).

The enablement of IOMMU in endpoint mode was verified on setup with two
Rock 5b:s, where the BDF of the Root Complex has BDF (00:00.0).

A Root Complex sending a TLP to the Endpoint will have Requester ID set
to the BDF of the initiator. On the EP side, the Requester ID will then
be used as the SID. This works fine if the Root Complex has a BDF that
matches the iommus DT property, however, if the Root Complex has any other
BDF, we will see something like:
arm-smmu-v3 fc900000.iommu: event: C_BAD_STREAMID client: (unassigned sid) sid: 0x1600 ssid: 0x0
on the endpoint side.

For PCIe controllers running in endpoint mode that always uses the
incoming Requester ID as the SID, the iommus DT property simply isn't
a viable solution. (Neither is iommu-map a viable solution, as there is
no enumeration done on the endpoint side.)

Thus, partly revert commit da92d3dfc8 ("arm64: dts: rockchip: enable the
mmu600_pcie IOMMU on the rk3588 SoC") by disabling the PCI IOMMU when
running the pcie3x4 PCIe controller in Endpoint mode.

Since the PCI IOMMU is working as expected in the normal case, keep it
enabled when running all PCIe controllers in Root Complex mode.

Fixes: da92d3dfc8 ("arm64: dts: rockchip: enable the mmu600_pcie IOMMU on the rk3588 SoC")
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/20250207143900.2047949-2-cassel@kernel.org
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2025-02-11 21:25:13 +01:00
Niklas Schnelle
2844ddbd54 s390/pci: Fix handling of isolated VFs
In contrast to the commit message of the fixed commit VFs whose parent
PF is not configured are not always isolated, that is put on their own
PCI domain. This is because for VFs to be added to an existing PCI
domain it is enough for that PCI domain to share the same topology ID or
PCHID. Such a matching PCI domain without a parent PF may exist when
a PF from the same PCI card created the domain with the VF being a child
of a different, non accessible, PF. While not causing technical issues
it makes the rules which VFs are isolated inconsistent.

Fix this by explicitly checking that the parent PF exists on the PCI
domain determined by the topology ID or PCHID before registering the VF.
This works because a parent PF which is under control of this Linux
instance must be enabled and configured at the point where its child VFs
appear because otherwise SR-IOV could not have been enabled on the
parent.

Fixes: 25f39d3dcb ("s390/pci: Ignore RID for isolated VFs")
Cc: stable@vger.kernel.org
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-02-11 19:35:08 +01:00
Niklas Schnelle
05793884a1 s390/pci: Pull search for parent PF out of zpci_iov_setup_virtfn()
This creates a new zpci_iov_find_parent_pf() function which a future
commit can use to find if a VF has a configured parent PF. Use
zdev->rid instead of zdev->devfn such that the new function can be used
before it has been decided if the RID will be exposed and zdev->devfn is
set. Also handle the hypotheical case that the RID is not available but
there is an otherwise matching zbus.

Fixes: 25f39d3dcb ("s390/pci: Ignore RID for isolated VFs")
Cc: stable@vger.kernel.org
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-02-11 19:35:08 +01:00
Heiko Carstens
6166caf3bb s390/bitops: Disable arch_test_bit() optimization for PROFILE_ALL_BRANCHES
With PROFILE_ALL_BRANCHES enabled gcc sometimes fails to handle
__builtin_constant_p() correctly:

   In function 'arch_test_bit',
       inlined from 'node_state' at include/linux/nodemask.h:423:9,
       inlined from 'warn_if_node_offline' at include/linux/gfp.h:252:2,
       inlined from '__alloc_pages_node_noprof' at include/linux/gfp.h:267:2,
       inlined from 'alloc_pages_node_noprof' at include/linux/gfp.h:296:9,
       inlined from 'vm_area_alloc_pages.constprop' at mm/vmalloc.c:3591:11:
>> arch/s390/include/asm/bitops.h:60:17: warning: 'asm' operand 2 probably does not match constraints
      60 |                 asm volatile(
         |                 ^~~
>> arch/s390/include/asm/bitops.h:60:17: error: impossible constraint in 'asm'

Therefore disable the optimization for this case. This is similar to
commit 63678eecec ("s390/preempt: disable __preempt_count_add()
optimization for PROFILE_ALL_BRANCHES")

Fixes: b2bc1b1a77 ("s390/bitops: Provide optimized arch_test_bit()")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202502091912.xL2xTCGw-lkp@intel.com/
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-02-11 19:35:08 +01:00
Ilya Leoshkevich
8d1d1e8d33 s390/configs: Remove CONFIG_LSM
s390 defconfig does not have BPF LSM, resulting in

    systemd[1]: bpf-restrict-fs: BPF LSM hook not enabled in the kernel, BPF LSM not supported.

with the respective kernels. The other architectures do not explicitly
set it, and the default values have BPF in them, so just drop it.

Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-02-11 19:35:08 +01:00
Patrick Bellasi
318e8c339c x86/cpu/kvm: SRSO: Fix possible missing IBPB on VM-Exit
In [1] the meaning of the synthetic IBPB flags has been redefined for a
better separation of concerns:
 - ENTRY_IBPB     -- issue IBPB on entry only
 - IBPB_ON_VMEXIT -- issue IBPB on VM-Exit only
and the Retbleed mitigations have been updated to match this new
semantics.

Commit [2] was merged shortly before [1], and their interaction was not
handled properly. This resulted in IBPB not being triggered on VM-Exit
in all SRSO mitigation configs requesting an IBPB there.

Specifically, an IBPB on VM-Exit is triggered only when
X86_FEATURE_IBPB_ON_VMEXIT is set. However:

 - X86_FEATURE_IBPB_ON_VMEXIT is not set for "spec_rstack_overflow=ibpb",
   because before [1] having X86_FEATURE_ENTRY_IBPB was enough. Hence,
   an IBPB is triggered on entry but the expected IBPB on VM-exit is
   not.

 - X86_FEATURE_IBPB_ON_VMEXIT is not set also when
   "spec_rstack_overflow=ibpb-vmexit" if X86_FEATURE_ENTRY_IBPB is
   already set.

   That's because before [1] this was effectively redundant. Hence, e.g.
   a "retbleed=ibpb spec_rstack_overflow=bpb-vmexit" config mistakenly
   reports the machine still vulnerable to SRSO, despite an IBPB being
   triggered both on entry and VM-Exit, because of the Retbleed selected
   mitigation config.

 - UNTRAIN_RET_VM won't still actually do anything unless
   CONFIG_MITIGATION_IBPB_ENTRY is set.

For "spec_rstack_overflow=ibpb", enable IBPB on both entry and VM-Exit
and clear X86_FEATURE_RSB_VMEXIT which is made superfluous by
X86_FEATURE_IBPB_ON_VMEXIT. This effectively makes this mitigation
option similar to the one for 'retbleed=ibpb', thus re-order the code
for the RETBLEED_MITIGATION_IBPB option to be less confusing by having
all features enabling before the disabling of the not needed ones.

For "spec_rstack_overflow=ibpb-vmexit", guard this mitigation setting
with CONFIG_MITIGATION_IBPB_ENTRY to ensure UNTRAIN_RET_VM sequence is
effectively compiled in. Drop instead the CONFIG_MITIGATION_SRSO guard,
since none of the SRSO compile cruft is required in this configuration.
Also, check only that the required microcode is present to effectively
enabled the IBPB on VM-Exit.

Finally, update the KConfig description for CONFIG_MITIGATION_IBPB_ENTRY
to list also all SRSO config settings enabled by this guard.

Fixes: 864bcaa38e ("x86/cpu/kvm: Provide UNTRAIN_RET_VM") [1]
Fixes: d893832d0e ("x86/srso: Add IBPB on VMEXIT") [2]
Reported-by: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Patrick Bellasi <derkling@google.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-02-11 10:07:52 -08:00
Marc Zyngier
8dbccafce3 KVM: arm64: Fix __pkvm_host_mkyoung_guest() return value
Don't use an uninitialised stack variable, and just return 0
on the non-error path.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202502100911.8c9DbtKD-lkp@intel.com/
Reviewed-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-02-10 09:58:16 +00:00
Christophe Leroy
61bcc752d1 powerpc/64s: Rewrite __real_pte() and __rpte_to_hidx() as static inline
Rewrite __real_pte() and __rpte_to_hidx() as static inline in order to
avoid following warnings/errors when building with 4k page size:

	  CC      arch/powerpc/mm/book3s64/hash_tlb.o
	arch/powerpc/mm/book3s64/hash_tlb.c: In function 'hpte_need_flush':
	arch/powerpc/mm/book3s64/hash_tlb.c:49:16: error: variable 'offset' set but not used [-Werror=unused-but-set-variable]
	   49 |         int i, offset;
	      |                ^~~~~~

	  CC      arch/powerpc/mm/book3s64/hash_native.o
	arch/powerpc/mm/book3s64/hash_native.c: In function 'native_flush_hash_range':
	arch/powerpc/mm/book3s64/hash_native.c:782:29: error: variable 'index' set but not used [-Werror=unused-but-set-variable]
	  782 |         unsigned long hash, index, hidx, shift, slot;
	      |                             ^~~~~

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202501081741.AYFwybsq-lkp@intel.com/
Fixes: ff31e10546 ("powerpc/mm/hash64: Store the slot information at the right offset for hugetlb")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/e0d340a5b7bd478ecbf245d826e6ab2778b74e06.1736706263.git.christophe.leroy@csgroup.eu
2025-02-10 10:01:22 +05:30
Christophe Leroy
dc9c5166c3 powerpc/code-patching: Disable KASAN report during patching via temporary mm
Erhard reports the following KASAN hit on Talos II (power9) with kernel 6.13:

[   12.028126] ==================================================================
[   12.028198] BUG: KASAN: user-memory-access in copy_to_kernel_nofault+0x8c/0x1a0
[   12.028260] Write of size 8 at addr 0000187e458f2000 by task systemd/1

[   12.028346] CPU: 87 UID: 0 PID: 1 Comm: systemd Tainted: G                T  6.13.0-P9-dirty #3
[   12.028408] Tainted: [T]=RANDSTRUCT
[   12.028446] Hardware name: T2P9D01 REV 1.01 POWER9 0x4e1202 opal:skiboot-bc106a0 PowerNV
[   12.028500] Call Trace:
[   12.028536] [c000000008dbf3b0] [c000000001656a48] dump_stack_lvl+0xbc/0x110 (unreliable)
[   12.028609] [c000000008dbf3f0] [c0000000006e2fc8] print_report+0x6b0/0x708
[   12.028666] [c000000008dbf4e0] [c0000000006e2454] kasan_report+0x164/0x300
[   12.028725] [c000000008dbf600] [c0000000006e54d4] kasan_check_range+0x314/0x370
[   12.028784] [c000000008dbf640] [c0000000006e6310] __kasan_check_write+0x20/0x40
[   12.028842] [c000000008dbf660] [c000000000578e8c] copy_to_kernel_nofault+0x8c/0x1a0
[   12.028902] [c000000008dbf6a0] [c0000000000acfe4] __patch_instructions+0x194/0x210
[   12.028965] [c000000008dbf6e0] [c0000000000ade80] patch_instructions+0x150/0x590
[   12.029026] [c000000008dbf7c0] [c0000000001159bc] bpf_arch_text_copy+0x6c/0xe0
[   12.029085] [c000000008dbf800] [c000000000424250] bpf_jit_binary_pack_finalize+0x40/0xc0
[   12.029147] [c000000008dbf830] [c000000000115dec] bpf_int_jit_compile+0x3bc/0x930
[   12.029206] [c000000008dbf990] [c000000000423720] bpf_prog_select_runtime+0x1f0/0x280
[   12.029266] [c000000008dbfa00] [c000000000434b18] bpf_prog_load+0xbb8/0x1370
[   12.029324] [c000000008dbfb70] [c000000000436ebc] __sys_bpf+0x5ac/0x2e00
[   12.029379] [c000000008dbfd00] [c00000000043a228] sys_bpf+0x28/0x40
[   12.029435] [c000000008dbfd20] [c000000000038eb4] system_call_exception+0x334/0x610
[   12.029497] [c000000008dbfe50] [c00000000000c270] system_call_vectored_common+0xf0/0x280
[   12.029561] --- interrupt: 3000 at 0x3fff82f5cfa8
[   12.029608] NIP:  00003fff82f5cfa8 LR: 00003fff82f5cfa8 CTR: 0000000000000000
[   12.029660] REGS: c000000008dbfe80 TRAP: 3000   Tainted: G                T   (6.13.0-P9-dirty)
[   12.029735] MSR:  900000000280f032 <SF,HV,VEC,VSX,EE,PR,FP,ME,IR,DR,RI>  CR: 42004848  XER: 00000000
[   12.029855] IRQMASK: 0
               GPR00: 0000000000000169 00003fffdcf789a0 00003fff83067100 0000000000000005
               GPR04: 00003fffdcf78a98 0000000000000090 0000000000000000 0000000000000008
               GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
               GPR12: 0000000000000000 00003fff836ff7e0 c000000000010678 0000000000000000
               GPR16: 0000000000000000 0000000000000000 00003fffdcf78f28 00003fffdcf78f90
               GPR20: 0000000000000000 0000000000000000 0000000000000000 00003fffdcf78f80
               GPR24: 00003fffdcf78f70 00003fffdcf78d10 00003fff835c7239 00003fffdcf78bd8
               GPR28: 00003fffdcf78a98 0000000000000000 0000000000000000 000000011f547580
[   12.030316] NIP [00003fff82f5cfa8] 0x3fff82f5cfa8
[   12.030361] LR [00003fff82f5cfa8] 0x3fff82f5cfa8
[   12.030405] --- interrupt: 3000
[   12.030444] ==================================================================

Commit c28c15b6d2 ("powerpc/code-patching: Use temporary mm for
Radix MMU") is inspired from x86 but unlike x86 is doesn't disable
KASAN reports during patching. This wasn't a problem at the begining
because __patch_mem() is not instrumented.

Commit 465cabc97b ("powerpc/code-patching: introduce
patch_instructions()") use copy_to_kernel_nofault() to copy several
instructions at once. But when using temporary mm the destination is
not regular kernel memory but a kind of kernel-like memory located
in user address space. Because it is not in kernel address space it is
not covered by KASAN shadow memory. Since commit e4137f0881 ("mm,
kasan, kmsan: instrument copy_from/to_kernel_nofault") KASAN reports
bad accesses from copy_to_kernel_nofault(). Here a bad access to user
memory is reported because KASAN detects the lack of shadow memory and
the address is below TASK_SIZE.

Do like x86 in commit b3fd8e83ad ("x86/alternatives: Use temporary
mm for text poking") and disable KASAN reports during patching when
using temporary mm.

Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Close: https://lore.kernel.org/all/20250201151435.48400261@yea/
Fixes: 465cabc97b ("powerpc/code-patching: introduce patch_instructions()")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/1c05b2a1b02ad75b981cfc45927e0b4a90441046.1738577687.git.christophe.leroy@csgroup.eu
2025-02-10 09:56:02 +05:30
Linus Torvalds
954a209f43 Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
 "ARM:

   - Correctly clean the BSS to the PoC before allowing EL2 to access it
     on nVHE/hVHE/protected configurations

   - Propagate ownership of debug registers in protected mode after the
     rework that landed in 6.14-rc1

   - Stop pretending that we can run the protected mode without a GICv3
     being present on the host

   - Fix a use-after-free situation that can occur if a vcpu fails to
     initialise the NV shadow S2 MMU contexts

   - Always evaluate the need to arm a background timer for fully
     emulated guest timers

   - Fix the emulation of EL1 timers in the absence of FEAT_ECV

   - Correctly handle the EL2 virtual timer, specially when HCR_EL2.E2H==0

  s390:

   - move some of the guest page table (gmap) logic into KVM itself,
     inching towards the final goal of completely removing gmap from the
     non-kvm memory management code.

     As an initial set of cleanups, move some code from mm/gmap into kvm
     and start using __kvm_faultin_pfn() to fault-in pages as needed;
     but especially stop abusing page->index and page->lru to aid in the
     pgdesc conversion.

  x86:

   - Add missing check in the fix to defer starting the huge page
     recovery vhost_task

   - SRSO_USER_KERNEL_NO does not need SYNTHESIZED_F"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (31 commits)
  KVM: x86/mmu: Ensure NX huge page recovery thread is alive before waking
  KVM: remove kvm_arch_post_init_vm
  KVM: selftests: Fix spelling mistake "initally" -> "initially"
  kvm: x86: SRSO_USER_KERNEL_NO is not synthesized
  KVM: arm64: timer: Don't adjust the EL2 virtual timer offset
  KVM: arm64: timer: Correctly handle EL1 timer emulation when !FEAT_ECV
  KVM: arm64: timer: Always evaluate the need for a soft timer
  KVM: arm64: Fix nested S2 MMU structures reallocation
  KVM: arm64: Fail protected mode init if no vgic hardware is present
  KVM: arm64: Flush/sync debug state in protected mode
  KVM: s390: selftests: Streamline uc_skey test to issue iske after sske
  KVM: s390: remove the last user of page->index
  KVM: s390: move PGSTE softbits
  KVM: s390: remove useless page->index usage
  KVM: s390: move gmap_shadow_pgt_lookup() into kvm
  KVM: s390: stop using lists to keep track of used dat tables
  KVM: s390: stop using page->index for non-shadow gmaps
  KVM: s390: move some gmap shadowing functions away from mm/gmap.c
  KVM: s390: get rid of gmap_translate()
  KVM: s390: get rid of gmap_fault()
  ...
2025-02-09 09:41:38 -08:00
Quentin Perret
eabc7aaef7 KVM: arm64: Simplify np-guest hypercalls
When the handling of a guest stage-2 permission fault races with an MMU
notifier, the faulting page might be gone from the guest's stage-2 by
the point we attempt to call (p)kvm_pgtable_stage2_relax_perms(). In the
normal KVM case, this leads to returning -EAGAIN which user_mem_abort()
handles correctly by simply re-entering the guest. However, the pKVM
hypercall implementation has additional logic to check the page state
using __check_host_shared_guest() which gets confused with absence of a
page mapped at the requested IPA and returns -ENOENT, hence breaking
user_mem_abort() and hilarity ensues.

Luckily, several of the hypercalls for managing the stage-2 page-table
of NP guests have no effect on the pKVM ownership tracking (wrprotect,
test_clear_young, mkyoung, and crucially relax_perms), so the extra
state checking logic is in fact not strictly necessary. So, to fix the
discrepancy between standard KVM and pKVM, let's just drop the
superfluous __check_host_shared_guest() logic from those hypercalls and
make the extra state checking a debug assertion dependent on
CONFIG_NVHE_EL2_DEBUG as we already do for other transitions.

Signed-off-by: Quentin Perret <qperret@google.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20250207145438.1333475-3-qperret@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-02-09 10:20:38 +00:00
Quentin Perret
c53fbdb60f KVM: arm64: Improve error handling from check_host_shared_guest()
The check_host_shared_guest() path expects to find a last-level valid
PTE in the guest's stage-2 page-table. However, it checks the PTE's
level before its validity, which makes it hard for callers to figure out
what went wrong.

To make error handling simpler, check the PTE's validity first.

Signed-off-by: Quentin Perret <qperret@google.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20250207145438.1333475-2-qperret@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-02-09 10:20:38 +00:00
Linus Torvalds
8b0582f509 Merge tag 'execve-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull execve fix from Kees Cook:
 "This is an alpha-specific fix, but since it touched ELF I was asked to
  carry it.

   - alpha/elf: Fix misc/setarch test of util-linux by removing 32bit
     support (Eric W. Biederman)"

* tag 'execve-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  alpha/elf: Fix misc/setarch test of util-linux by removing 32bit support
2025-02-08 13:59:24 -08:00
Linus Torvalds
a5057ded6e Merge tag 'x86-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fix from Ingo Molnar:
 "Fix a build regression on GCC 15 builds, caused by GCC changing the
  default C version that is overriden in the main Makefile but not in
  the x86 boot code Makefile"

* tag 'x86-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Use '-std=gnu11' to fix build with GCC 15
2025-02-08 12:04:00 -08:00
Sean Christopherson
c631a2de7a perf/x86/intel: Ensure LBRs are disabled when a CPU is starting
Explicitly clear DEBUGCTL.LBR when a CPU is starting, prior to purging the
LBR MSRs themselves, as at least one system has been found to transfer
control to the kernel with LBRs enabled (it's unclear whether it's a BIOS
flaw or a CPU goof).  Because the kernel preserves the original DEBUGCTL,
even when toggling LBRs, leaving DEBUGCTL.LBR as is results in running
with LBRs enabled at all times.

Closes: https://lore.kernel.org/all/c9d8269bff69f6359731d758e3b1135dedd7cc61.camel@redhat.com
Reported-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20250131010721.470503-1-seanjc@google.com
2025-02-08 15:47:26 +01:00
Kan Liang
47a973fd75 perf/x86/intel: Fix ARCH_PERFMON_NUM_COUNTER_LEAF
The EAX of the CPUID Leaf 023H enumerates the mask of valid sub-leaves.
To tell the availability of the sub-leaf 1 (enumerate the counter mask),
perf should check the bit 1 (0x2) of EAS, rather than bit 0 (0x1).

The error is not user-visible on bare metal. Because the sub-leaf 0 and
the sub-leaf 1 are always available. However, it may bring issues in a
virtualization environment when a VMM only enumerates the sub-leaf 0.

Introduce the cpuid35_e?x to replace the macros, which makes the
implementation style consistent.

Fixes: eb467aaac2 ("perf/x86/intel: Support Architectural PerfMon Extension leaf")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20250129154820.3755948-3-kan.liang@linux.intel.com
2025-02-08 15:47:25 +01:00
Kan Liang
0a55615013 perf/x86/intel: Clean up PEBS-via-PT on hybrid
The PEBS-via-PT feature is exposed for the e-core of some hybrid
platforms, e.g., ADL and MTL. But it never works.

$ dmesg | grep PEBS
[    1.793888] core: cpu_atom PMU driver: PEBS-via-PT

$ perf record -c 1000 -e '{intel_pt/branch=0/,
cpu_atom/cpu-cycles,aux-output/pp}' -C8
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument)
for event (cpu_atom/cpu-cycles,aux-output/pp).
"dmesg | grep -i perf" may provide additional information.

The "PEBS-via-PT" is printed if the corresponding bit of per-PMU
capabilities is set. Since the feature is supported by the e-core HW,
perf sets the bit for e-core. However, for Intel PT, if a feature is not
supported on all CPUs, it is not supported at all. The PEBS-via-PT event
cannot be created successfully.

The PEBS-via-PT is no longer enumerated on the latest hybrid platform. It
will be deprecated on future platforms with Arch PEBS. Let's remove it
from the existing hybrid platforms.

Fixes: d9977c43bf ("perf/x86: Register hybrid PMUs")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20250129154820.3755948-2-kan.liang@linux.intel.com
2025-02-08 15:47:25 +01:00
Dhananjay Ugwekar
469c76a83b perf/x86/rapl: Fix the error checking order
After the commit b4943b8bfc ("perf/x86/rapl: Add core energy counter
support for AMD CPUs"), the default "perf record"/"perf top" command is
broken in systems where there isn't a PMU registered for type
PERF_TYPE_RAW.

This is due to the change in order of error checks in rapl_pmu_event_init()
Due to which we return -EINVAL instead of -ENOENT, when we reach here from
the fallback loop in perf_init_event().

Move the "PMU and event type match" back to the beginning of the function
so that we return -ENOENT early on.

Closes: https://lore.kernel.org/all/uv7mz6vew2bzgre5jdpmwldxljp5djzmuiksqdcdwipfm4zm7w@ribobcretidk/
Fixes: b4943b8bfc ("perf/x86/rapl: Add core energy counter support for AMD CPUs")
Reported-by: Koichiro Den <koichiro.den@canonical.com>
Signed-off-by: Dhananjay Ugwekar <dhananjay.ugwekar@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20250129080513.30353-1-dhananjay.ugwekar@amd.com
2025-02-08 15:47:25 +01:00
Radu Rendec
875d742cf5 arm64: cacheinfo: Avoid out-of-bounds write to cacheinfo array
The loop that detects/populates cache information already has a bounds
check on the array size but does not account for cache levels with
separate data/instructions cache. Fix this by incrementing the index
for any populated leaf (instead of any populated level).

Fixes: 5d425c1865 ("arm64: kernel: add support for cpu cache information")

Signed-off-by: Radu Rendec <rrendec@redhat.com>
Link: https://lore.kernel.org/r/20250206174420.2178724-1-rrendec@redhat.com
Signed-off-by: Will Deacon <will@kernel.org>
2025-02-07 09:57:56 +00:00
Nathan Chancellor
ca0f4fe7cf arm64: Handle .ARM.attributes section in linker scripts
A recent LLVM commit [1] started generating an .ARM.attributes section
similar to the one that exists for 32-bit, which results in orphan
section warnings (or errors if CONFIG_WERROR is enabled) from the linker
because it is not handled in the arm64 linker scripts.

  ld.lld: error: arch/arm64/kernel/vdso/vgettimeofday.o:(.ARM.attributes) is being placed in '.ARM.attributes'
  ld.lld: error: arch/arm64/kernel/vdso/vgetrandom.o:(.ARM.attributes) is being placed in '.ARM.attributes'

  ld.lld: error: vmlinux.a(lib/vsprintf.o):(.ARM.attributes) is being placed in '.ARM.attributes'
  ld.lld: error: vmlinux.a(lib/win_minmax.o):(.ARM.attributes) is being placed in '.ARM.attributes'
  ld.lld: error: vmlinux.a(lib/xarray.o):(.ARM.attributes) is being placed in '.ARM.attributes'

Discard the new sections in the necessary linker scripts to resolve the
warnings, as the kernel and vDSO do not need to retain it, similar to
the .note.gnu.property section.

Cc: stable@vger.kernel.org
Fixes: b3e5d80d0c ("arm64/build: Warn on orphan section placement")
Link: ee99c4d484 [1]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250206-arm64-handle-arm-attributes-in-linker-script-v3-1-d53d169913eb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2025-02-07 09:56:57 +00:00
Geert Uytterhoeven
29a61a1f40 genirq: Remove leading space from irq_chip::irq_print_chip() callbacks
The space separator was factored out from the multiple chip name prints,
but several irq_chip::irq_print_chip() callbacks still print a leading
space.  Remove the superfluous double spaces.

Fixes: 9d9f204bdf ("genirq/proc: Add missing space separator back")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/893f7e9646d8933cd6786d5a1ef3eb076d263768.1738764803.git.geert+renesas@glider.be
2025-02-07 08:56:01 +01:00
Linus Torvalds
5b734b49de Merge tag 'for-linus-6.14-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
 "Three fixes for xen_hypercall_hvm() that was introduced in the 6.13
  cycle"

* tag 'for-linus-6.14-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: remove unneeded dummy push from xen_hypercall_hvm()
  x86/xen: add FRAME_END to xen_hypercall_hvm()
  x86/xen: fix xen_hypercall_hvm() to not clobber %rbx
2025-02-06 12:25:35 -08:00
Eric W. Biederman
b029628be2 alpha/elf: Fix misc/setarch test of util-linux by removing 32bit support
Richard Henderson <richard.henderson@linaro.org> writes[1]:

> There was a Spec benchmark (I forget which) which was memory bound and ran
> twice as fast with 32-bit pointers.
>
> I copied the idea from DEC to the ELF abi, but never did all the other work
> to allow the toolchain to take advantage.
>
> Amusingly, a later Spec changed the benchmark data sets to not fit into a
> 32-bit address space, specifically because of this.
>
> I expect one could delete the ELF bit and personality and no one would
> notice. Not even the 10 remaining Alpha users.

In [2] it was pointed out that parts of setarch weren't working
properly on alpha because it has it's own SET_PERSONALITY
implementation.  In the discussion that followed Richard Henderson
pointed out that the 32bit pointer support for alpha was never
completed.

Fix this by removing alpha's 32bit pointer support.

As a bit of paranoia refuse to execute any alpha binaries that have
the EF_ALPHA_32BIT flag set.  Just in case someone somewhere has
binaries that try to use alpha's 32bit pointer support.

Link: https://lkml.kernel.org/r/CAFXwXrkgu=4Qn-v1PjnOR4SG0oUb9LSa0g6QXpBq4ttm52pJOQ@mail.gmail.com [1]
Link: https://lkml.kernel.org/r/20250103140148.370368-1-glaubitz@physik.fu-berlin.de [2]
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/87y0zfs26i.fsf_-_@email.froward.int.ebiederm.org
Signed-off-by: Kees Cook <kees@kernel.org>
2025-02-06 07:35:38 -08:00
Vaishnav Achath
c7691aec5e arm64: defconfig: Enable TISCI Interrupt Router and Aggregator
Enable TISCI Interrupt Router and Interrupt Aggregator drivers.
These IPs are found in all TI K3 SoCs like J721E, AM62X and is required
for core functionality like DMA, GPIO Interrupts which is necessary
during boot, thus make them built-in.

bloat-o-meter summary on vmlinux:
	add/remove: 460/1 grow/shrink: 4/0 up/down: 162483/-8 (162475)
	...
	Total: Before=31615984, After=31778459, chg +0.51%

These configs were previously selected for ARCH_K3 in respective Kconfigs
till commit b8b26ae398 ("irqchip/ti-sci-inta : Add module build support")
and commit 2d95ffaecb ("irqchip/ti-sci-intr: Add module build support")
dropped them and few driver configs (TI_K3_UDMA, TI_K3_RINGACC)
dependent on these also got disabled due to this. While re-enabling the
TI_SCI_INT_*_IRQCHIP configs, these configs with missing dependencies
(which are already part of arm64 defconfig) also get re-enabled which
explains the slightly larger size increase from the bloat-o-meter summary.

Fixes: 2d95ffaecb ("irqchip/ti-sci-intr: Add module build support")
Fixes: b8b26ae398 ("irqchip/ti-sci-inta : Add module build support")

Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com>
Tested-by: Dhruva Gole <d-gole@ti.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/r/20250205062229.3869081-1-vaishnav.a@ti.com
Signed-off-by: Nishanth Menon <nm@ti.com>
2025-02-06 09:10:24 +05:30
Juergen Gross
aaf5eefd37 x86/xen: remove unneeded dummy push from xen_hypercall_hvm()
Stack alignment of the kernel in 64-bit mode is 8, not 16, so the
dummy push in xen_hypercall_hvm() for aligning the stack to 16 bytes
can be removed.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2025-02-05 17:23:22 +01:00
Juergen Gross
0bd797b801 x86/xen: add FRAME_END to xen_hypercall_hvm()
xen_hypercall_hvm() is missing a FRAME_END at the end, add it.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202502030848.HTNTTuo9-lkp@intel.com/
Fixes: b4845bb638 ("x86/xen: add central hypercall functions")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2025-02-05 17:23:20 +01:00
Juergen Gross
98a5cfd232 x86/xen: fix xen_hypercall_hvm() to not clobber %rbx
xen_hypercall_hvm(), which is used when running as a Xen PVH guest at
most only once during early boot, is clobbering %rbx. Depending on
whether the caller relies on %rbx to be preserved across the call or
not, this clobbering might result in an early crash of the system.

This can be avoided by using an already saved register instead of %rbx.

Fixes: b4845bb638 ("x86/xen: add central hypercall functions")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2025-02-05 17:23:15 +01:00
Sean Christopherson
43fb96ae78 KVM: x86/mmu: Ensure NX huge page recovery thread is alive before waking
When waking a VM's NX huge page recovery thread, ensure the thread is
actually alive before trying to wake it.  Now that the thread is spawned
on-demand during KVM_RUN, a VM without a recovery thread is reachable via
the related module params.

  BUG: kernel NULL pointer dereference, address: 0000000000000040
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  RIP: 0010:vhost_task_wake+0x5/0x10
  Call Trace:
   <TASK>
   set_nx_huge_pages+0xcc/0x1e0 [kvm]
   param_attr_store+0x8a/0xd0
   module_attr_store+0x1a/0x30
   kernfs_fop_write_iter+0x12f/0x1e0
   vfs_write+0x233/0x3e0
   ksys_write+0x60/0xd0
   do_syscall_64+0x5b/0x160
   entry_SYSCALL_64_after_hwframe+0x4b/0x53
  RIP: 0033:0x7f3b52710104
   </TASK>
  Modules linked in: kvm_intel kvm
  CR2: 0000000000000040

Fixes: 931656b9e2 ("kvm: defer huge page recovery vhost task to later")
Cc: stable@vger.kernel.org
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20250124234623.3609069-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-04 11:28:21 -05:00
Paolo Bonzini
6f61269495 KVM: remove kvm_arch_post_init_vm
The only statement in a kvm_arch_post_init_vm implementation
can be moved into the x86 kvm_arch_init_vm.  Do so and remove all
traces from architecture-independent code.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-04 11:27:45 -05:00
Paolo Bonzini
5e21d0c5b9 Merge tag 'kvmarm-fixes-6.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 fixes for 6.14, take #1

- Correctly clean the BSS to the PoC before allowing EL2 to access it
  on nVHE/hVHE/protected configurations

- Propagate ownership of debug registers in protected mode after
  the rework that landed in 6.14-rc1

- Stop pretending that we can run the protected mode without a GICv3
  being present on the host

- Fix a use-after-free situation that can occur if a vcpu fails to
  initialise the NV shadow S2 MMU contexts

- Always evaluate the need to arm a background timer for fully emulated
  guest timers

- Fix the emulation of EL1 timers in the absence of FEAT_ECV

- Correctly handle the EL2 virtual timer, specially when HCR_EL2.E2H==0
2025-02-04 11:14:53 -05:00
Paolo Bonzini
35441cdd50 Merge tag 'kvm-s390-next-6.14-2' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
- some selftest fixes
- move some kvm-related functions from mm into kvm
- remove all usage of page->index and page->lru from kvm
- fixes and cleanups for vsie
2025-02-04 11:14:21 -05:00