linux-stable.git/arch/powerpc, branch v6.3

Merge tag 'powerpc-6.3-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2023-04-16T16:55:18+00:00

Pull powerpc fix from Michael Ellerman:

 - A fix for NUMA distance handling in the pseries SCM (pmem) driver.

   Thanks to Aneesh Kumar K.V.

* tag 'powerpc-6.3-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/papr_scm: Update the NUMA distance table for the target node

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

2023-04-04T18:29:37+00:00

Pull kvm fixes from Paolo Bonzini:
 "PPC:
   - Hide KVM_CAP_IRQFD_RESAMPLE if XIVE is enabled

  s390:
   - Fix handling of external interrupts in protected guests

  x86:
   - Resample the pending state of IOAPIC interrupts when unmasking them

   - Fix usage of Hyper-V "enlightened TLB" on AMD

   - Small fixes to real mode exceptions

   - Suppress pending MMIO write exits if emulator detects exception

  Documentation:
   - Fix rST syntax"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  docs: kvm: x86: Fix broken field list
  KVM: PPC: Make KVM_CAP_IRQFD_RESAMPLE platform dependent
  KVM: s390: pv: fix external interruption loop not always detected
  KVM: nVMX: Do not report error code when synthesizing VM-Exit from Real Mode
  KVM: x86: Clear "has_error_code", not "error_code", for RM exception injection
  KVM: x86: Suppress pending MMIO write exits if emulator detects exception
  KVM: x86/ioapic: Resample the pending state of an IRQ when unmasking
  KVM: irqfd: Make resampler_list an RCU list
  KVM: SVM: Flush Hyper-V TLB when required

powerpc/papr_scm: Update the NUMA distance table for the target node

2023-04-04T12:08:35+00:00

Platform device helper routines won't update the NUMA distance table
while creating a platform device, even if the device is present on a
NUMA node that doesn't have memory or CPU. This is especially true for
pmem devices. If the target node of the pmem device is not online, we
find the nearest online node to the device and associate the pmem device
with that online node. To find the nearest online node, we should have
the numa distance table updated correctly. Update the distance
information during the device probe.

For a papr scm device on NUMA node 3 distance_lookup_table value for
distance_ref_points_depth = 2 before and after fix is below:

Before fix:
  node 3 distance depth 0  - 0
  node 3 distance depth 1  - 0
  node 4 distance depth 0  - 4
  node 4 distance depth 1  - 2
  node 5 distance depth 0  - 5
  node 5 distance depth 1  - 1

After fix
  node 3 distance depth 0  - 3
  node 3 distance depth 1  - 1
  node 4 distance depth 0  - 4
  node 4 distance depth 1  - 2
  node 5 distance depth 0  - 5
  node 5 distance depth 1  - 1

Without the fix, the nearest numa node to the pmem device (NUMA node 3)
will be picked as 4. After the fix, we get the correct numa node which
is 5.

Fixes: da1115fdbd6e ("powerpc/nvdimm: Pick nearby online node if the device node is not online")
Signed-off-by: Aneesh Kumar K.V 
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230404041433.1781804-1-aneesh.kumar@linux.ibm.com

Merge tag 'powerpc-6.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2023-04-02T17:01:56+00:00

Pull powerpc fixes from Michael Ellerman:

 - Fix a false positive warning in __pte_needs_flush() (with DEBUG_VM=y)

 - Fix oops when a PF_IO_WORKER thread tries to core dump

 - Don't try to reconfigure VAS when it's disabled

Thanks to Benjamin Gray, Haren Myneni, Jens Axboe, Nathan Lynch, and
Russell Currey.

* tag 'powerpc-6.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/pseries/vas: Ignore VAS update for DLPAR if copy/paste is not enabled
  powerpc: Don't try to copy PPR for task with NULL pt_regs
  powerpc/64s: Fix __pte_needs_flush() false positive warning

KVM: PPC: Make KVM_CAP_IRQFD_RESAMPLE platform dependent

2023-03-31T15:19:05+00:00

When introduced, IRQFD resampling worked on POWER8 with XICS. However
KVM on POWER9 has never implemented it - the compatibility mode code
("XICS-on-XIVE") misses the kvm_notify_acked_irq() call and the native
XIVE mode does not handle INTx in KVM at all.

This moved the capability support advertising to platforms and stops
advertising it on XIVE, i.e. POWER9 and later.

Signed-off-by: Alexey Kardashevskiy 
Acked-by: Anup Patel 
Acked-by: Nicholas Piggin 
Message-Id: <20220504074807.3616813-1-aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini

powerpc/pseries/vas: Ignore VAS update for DLPAR if copy/paste is not enabled

2023-03-29T12:01:35+00:00

The hypervisor supports user-mode NX from Power10.

pseries_vas_dlpar_cpu() is called from lparcfg_write() to update VAS
windows for DLPAR event in shared processor mode and the kernel gets
-ENOTSUPP for HCALLs if the user-mode NX is not supported. The current
VAS implementation also supports only with Radix page tables. Whereas in
dedicated processor mode, pseries_vas_notifier() is registered only if
the copy/paste feature is enabled. So instead of displaying HCALL error
messages, update VAS capabilities if the copy/paste feature is
available.

This patch ignores updating VAS capabilities in pseries_vas_dlpar_cpu()
and returns success if the copy/paste feature is not enabled. Then
lparcfg_write() completes the processor DLPAR operations without any
failures.

Fixes: 2147783d6bf0 ("powerpc/pseries: Use lparcfg to reconfig VAS windows for DLPAR CPU")
Cc: stable@vger.kernel.org # v6.1+
Signed-off-by: Haren Myneni 
Reviewed-by: Nathan Lynch 
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/1d0e727e7dbd9a28627ef08ca9df9c86a50175e2.camel@linux.ibm.com

powerpc: Don't try to copy PPR for task with NULL pt_regs

2023-03-28T11:11:41+00:00

powerpc sets up PF_KTHREAD and PF_IO_WORKER with a NULL pt_regs, which
from my (arguably very short) checking is not commonly done for other
archs. This is fine, except when PF_IO_WORKER's have been created and
the task does something that causes a coredump to be generated. Then we
get this crash:

  Kernel attempted to read user page (160) - exploit attempt? (uid: 1000)
  BUG: Kernel NULL pointer dereference on read at 0x00000160
  Faulting instruction address: 0xc0000000000c3a60
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=32 NUMA pSeries
  Modules linked in: bochs drm_vram_helper drm_kms_helper xts binfmt_misc ecb ctr syscopyarea sysfillrect cbc sysimgblt drm_ttm_helper aes_generic ttm sg libaes evdev joydev virtio_balloon vmx_crypto gf128mul drm dm_mod fuse loop configfs drm_panel_orientation_quirks ip_tables x_tables autofs4 hid_generic usbhid hid xhci_pci xhci_hcd usbcore usb_common sd_mod
  CPU: 1 PID: 1982 Comm: ppc-crash Not tainted 6.3.0-rc2+ #88
  Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries
  NIP:  c0000000000c3a60 LR: c000000000039944 CTR: c0000000000398e0
  REGS: c0000000041833b0 TRAP: 0300   Not tainted  (6.3.0-rc2+)
  MSR:  800000000280b033   CR: 88082828  XER: 200400f8
  ...
  NIP memcpy_power7+0x200/0x7d0
  LR  ppr_get+0x64/0xb0
  Call Trace:
    ppr_get+0x40/0xb0 (unreliable)
    __regset_get+0x180/0x1f0
    regset_get_alloc+0x64/0x90
    elf_core_dump+0xb98/0x1b60
    do_coredump+0x1c34/0x24a0
    get_signal+0x71c/0x1410
    do_notify_resume+0x140/0x6f0
    interrupt_exit_user_prepare_main+0x29c/0x320
    interrupt_exit_user_prepare+0x6c/0xa0
    interrupt_return_srr_user+0x8/0x138

Because ppr_get() is trying to copy from a PF_IO_WORKER with a NULL
pt_regs.

Check for a valid pt_regs in both ppc_get/ppr_set, and return an error
if not set. The actual error value doesn't seem to be important here, so
just pick -EINVAL.

Fixes: fa439810cc1b ("powerpc/ptrace: Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Jens Axboe 
[mpe: Trim oops in change log, add Fixes & Cc stable]
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/d9f63344-fe7c-56ae-b420-4a1a04a2ae4c@kernel.dk

powerpc/64s: Fix __pte_needs_flush() false positive warning

2023-03-28T10:37:23+00:00

Userspace PROT_NONE ptes set _PAGE_PRIVILEGED, triggering a false
positive debug assertion that __pte_flags_need_flush() is not called
on a kernel mapping.

Detect when it is a userspace PROT_NONE page by checking the required
bits of PAGE_NONE are set, and none of the RWX bits are set.
pte_protnone() is insufficient here because it always returns 0 when
CONFIG_NUMA_BALANCING=n.

Fixes: b11931e9adc1 ("powerpc/64s: add pte_needs_flush and huge_pmd_needs_flush")
Cc: stable@vger.kernel.org # v6.1+
Reported-by: Russell Currey 
Signed-off-by: Benjamin Gray 
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230302225947.81083-1-bgray@linux.ibm.com

kasan, powerpc: don't rename memintrinsics if compiler adds prefixes

2023-03-24T00:18:33+00:00

With appropriate compiler support [1], KASAN builds use __asan prefixed
meminstrinsics, and KASAN no longer overrides memcpy/memset/memmove.

If compiler support is detected (CC_HAS_KASAN_MEMINTRINSIC_PREFIX), define
memintrinsics normally (do not prefix '__').

On powerpc, KASAN is the only user of __mem functions, which are used to
define instrumented memintrinsics.  Alias the normal versions for KASAN to
use in its implementation.

Link: https://lore.kernel.org/all/20230224085942.1791837-1-elver@google.com/ [1]
Link: https://lore.kernel.org/oe-kbuild-all/202302271348.U5lvmo0S-lkp@intel.com/
Link: https://lkml.kernel.org/r/20230227094726.3833247-1-elver@google.com
Signed-off-by: Marco Elver 
Reported-by: kernel test robot 
Acked-by: Michael Ellerman 	[powerpc]
Cc: Alexander Potapenko 
Cc: Andrey Konovalov 
Cc: Andrey Ryabinin 
Cc: Christophe Leroy 
Cc: Daniel Axtens 
Cc: Dmitry Vyukov 
Cc: Liam R. Howlett 
Cc: Nicholas Piggin 
Cc: Vincenzo Frascino 
Signed-off-by: Andrew Morton

powerpc/mm: Fix false detection of read faults

2023-03-15T09:48:53+00:00

To support detection of read faults with Radix execute-only memory, the
vma_is_accessible() check in access_error() (which checks for PROT_NONE)
was replaced with a check to see if VM_READ was missing, and if so,
returns true to assert the fault was caused by a bad read.

This is incorrect, as it ignores that both VM_WRITE and VM_EXEC imply
read on powerpc, as defined in protection_map[].  This causes mappings
containing VM_WRITE or VM_EXEC without VM_READ to misreport the cause of
page faults, since the MMU is still allowing reads.

Correct this by restoring the original vma_is_accessible() check for
PROT_NONE mappings, and adding a separate check for Radix PROT_EXEC-only
mappings.

Fixes: 395cac7752b9 ("powerpc/mm: Support execute-only memory on the Radix MMU")
Reported-by: Michal Suchánek 
Link: https://lore.kernel.org/r/20230308152702.GR19419@kitsune.suse.cz
Tested-by: Benjamin Gray 
Signed-off-by: Russell Currey 
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230310050834.63105-1-ruscur@russell.cc