Static variables do not need to be initialised to 0, because compiler
will initialise all uninitialised statics to 0. Thus, remove the
unneeded initializations.
Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
Message-Id: <20220508022910.98481-1-wangborong@cdjrlc.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Don't use numeric labels for long jumps, use named local labels instead.
Avoid conditional label definition.
No functional changes.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

When fast_store_prohibited needs to go to the C-level exception handler
it leaves TLB entry that caused page fault in the TLB. If the faulting
task gets switched to a different CPU and completes page table update
there the TLB entry will get out of sync with the page table which may
cause a livelock on access to that page.
Invalidate faulting TLB entry on a slow path exit from the
fast_store_prohibited.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Secondary reset vector is defined, compiled and used when
CONFIG_SECONDARY_RESET_VECTOR is enabled, not only on SMP.
Make declarations of _SecondaryResetVector_text_* symbols available
accordingly.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

When irq-xtensa-mx chip is used in non-SMP configuration its
irq_set_affinity callback is not called leaving IRQ affinity set empty.
As a result IRQ delivery does not work in that configuration.
Initialize IRQ affinity of the xtensa MX interrupt distributor to CPU 0
for all external IRQ lines.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

xtensa kernels successfully build and run with
CONFIG_DEBUG_VM_PGTABLE=y, enable arch support for it.
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Define ARCH_HIBERNATION_POSSIBLE in Kconfig and implement hibernation
callbacks.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Current coprocessor support on xtensa only works correctly on
uniprocessor configurations. Make it work on SMP too and keep it lazy.

Make coprocessor_owner array per-CPU and move it to struct exc_table for
easy access from the fast_coprocessor exception handler. Allow task to
have live coprocessors only on single CPU, record this CPU number in the
struct thread_info::cp_owner_cpu. Change struct thread_info::cpenable
meaning to be 'coprocessors live on cp_owner_cpu'.
Introduce C-level coprocessor exception handler that flushes and
releases live coprocessors of the task taking 'coprocessor disabled'
exception and call it from the fast_coprocessor handler when the task
has live coprocessors on other CPU.
Make coprocessor_flush_all and coprocessor_release_all work correctly
when called from any CPU by sending IPI to the cp_owner_cpu. Add
function coprocessor_flush_release_all to do flush followed by release
atomically. Add function local_coprocessors_flush_release_all to flush
and release all coprocessors on the local CPU and use it to flush
coprocessor contexts from the CPU that goes offline.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

coprocessor_flush is an ordinary function, it can use all registers.
Don't reserve stack frame for it and use a7 to preserve a0 around the
context saving call.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Both tables share the same offset field but the different function
pointers. Merge them into single table with 3-element entries to reduce
code and data duplication.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

xtensa_xsr does the XSR instruction for the specified special register.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

In order to let drivers use xtensa coprocessors on behalf of the calling
process the kernel must handle coprocessor exceptions from the kernel
mode the same way as from the user mode.

This is not sufficient to allow using coprocessors transparently in IRQ
or softirq context. Should such users exist they must be aware of the
context and do the right thing, e.g. preserve the coprocessor state and
resore it after use.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Instead of emulating call0 in fast_coprocessor use that opcode directly.
Use 'ret' instead of 'jx a0'.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Use xtensa_set_sr instead of inline assembly.
Rename local variable exc_table in early_trap_init to avoid conflict
with per-CPU variable of the same name.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Drop 'extern' from all function declarations. Add parameter names in
declarations.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Exception handlers are currently passed as void pointers because they
may have one or two parameters. Only two handlers uses the second
parameter and it is available in the struct pt_regs anyway. Make all
handlers have only one parameter, introduce xtensa_exception_handler
type for handlers and use it in trap_set_handler.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Drop 'extern' from all function declarations and move those that need to
be visible from traps.c to traps.h. Add 'asmlinkage' to declarations of
fucntions defined in assembly. Add 'static' to declarations and
definitions only used locally. Add argument names in declarations.
Drop unused second argument from do_multihit and do_page_fault.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Prefix arch-specific barrier macros with '__' to make use of instrumented
generic macros.
Prefix arch-specific bitops with 'arch_' to make use of instrumented
generic functions.
Provide stubs for 64-bit atomics when building with KCSAN.
Disable KCSAN instrumentation in arch/xtensa/boot.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Marco Elver <elver@google.com>

There's no direct cputime_t manipulation in the xtensa arch code, so
generic virt CPU accounting may be enabled.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Put user exit context tracking call on the common kernel entry/exit path
(function calls are impossible at earlier kernel entry stages because
PS.EXCM is not cleared yet). Put user entry context tracking call on the
user exit path. Syscalls go through this common code too, so nothing
specific needs to be done for them.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Using plain register names is prone to errors when code is changed and
new calls are added between the register load and use. Change plain
register names to abi_* names in the call-heavy part of the kernel exit
code to clearly indicate what's supposed to be preserved and what's not.
Re-align code while at it.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Context tracking call must be done after hardirq tracking call,
otherwise lockdep_assert_irqs_disabled called from rcu_eqs_exit gives
a warning. To avoid context tracking logic duplication for IRQ/exception
entry paths move trace_hardirqs_off call back to common entry code.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

KERNEL_STACK_OVERFLOW_CHECK is incomplete and have never been enabled.
Remove it.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Many xtensa CPU cores without full MMU still have memory protection
features capable of raising exceptions for invalid instruction
fetches/data access. Allow handling such exceptions. This improves
behavior of processes that pass invalid memory pointers to syscalls in
noMMU configs: in case of exception the kernel instead of killing the
process is now able to return -EINVAL from a syscall.

Introduce CONFIG_PFAULT that controls whether protection fault code is
enabled and register handlers for common memory protection exceptions
when it is enabled.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Move full MMU-specific code into a separate function to isolate it from
more generic do_page_fault code. No functional changes.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

asid_cache is only useful with full MMU, but fault.c is also useful with
MPU. Move asid_cache definition to MMU-specific source file.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Instead of storing pointers to callback functions in the
struct iss_net_private::tp move them to struct struct iss_net_ops and
store a const pointer to it. Make static const tuntap_ops structure with
tuntap callbacks and initialize tp.net_ops with it in the tuntap_probe.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Per-device locking in the ISS network driver is used to protect poll
timer and stats updates. Stat collection is not protected.
Remove per-device locking everywhere except the stats updates. Replace
ndo_get_stats callback with ndo_get_stats64 and use proper locking there
as well.
As a side effect this fixes possible deadlock between iss_net_close
and iss_net_timer.

Reported by: Duoming Zhou <duoming@zju.edu.cn>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

iss_net_set_mac is just a copy of eth_mac_addr with pointless locking.
Drop this function and replace it with eth_mac_addr.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

opened_list is used to poll all opened devices in the timer callback,
but there's individual timer that is associated with each device.
Drop opened_list and only poll the device that is associated with the
timer in the timer callback.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Internal labels in the memmove implementation don't need to be visible,
localize them by prefixing their names with '.L'.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Pull kvm fixes from Paolo Bonzini:
 "ARM:

   - Take care of faults occuring between the PARange and IPA range by
     injecting an exception

   - Fix S2 faults taken from a host EL0 in protected mode

   - Work around Oops caused by a PMU access from a 32bit guest when PMU
     has been created. This is a temporary bodge until we fix it for
     good.

  x86:

   - Fix potential races when walking host page table

   - Fix shadow page table leak when KVM runs nested

   - Work around bug in userspace when KVM synthesizes leaf 0x80000021
     on older (pre-EPYC) or Intel processors

  Generic (but affects only RISC-V):

   - Fix bad user ABI for KVM_EXIT_SYSTEM_EVENT"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: work around QEMU issue with synthetic CPUID leaves
  Revert "x86/mm: Introduce lookup_address_in_mm()"
  KVM: x86/mmu: fix potential races when walking host page table
  KVM: fix bad user ABI for KVM_EXIT_SYSTEM_EVENT
  KVM: x86/mmu: Do not create SPTEs for GFNs that exceed host.MAXPHYADDR
  KVM: arm64: Inject exception on out-of-IPA-range translation fault
  KVM/arm64: Don't emulate a PMU for 32-bit guests if feature not set
  KVM: arm64: Handle host stage-2 faults from 32-bit EL0

Pull x86 fixes from Borislav Petkov:

 - A fix to disable PCI/MSI[-X] masking for XEN_HVM guests as that is
   solely controlled by the hypervisor

 - A build fix to make the function prototype (__warn()) as visible as
   the definition itself

 - A bunch of objtool annotation fixes which have accumulated over time

 - An ORC unwinder fix to handle bad input gracefully

 - Well, we thought the microcode gets loaded in time in order to
   restore the microcode-emulated MSRs but we thought wrong. So there's
   a fix for that to have the ordering done properly

 - Add new Intel model numbers

 - A spelling fix

* tag 'x86_urgent_for_v5.18_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/pci/xen: Disable PCI/MSI[-X] masking for XEN_HVM guests
  bug: Have __warn() prototype defined unconditionally
  x86/Kconfig: fix the spelling of 'becoming' in X86_KERNEL_IBT config
  objtool: Use offstr() to print address of missing ENDBR
  objtool: Print data address for "!ENDBR" data warnings
  x86/xen: Add ANNOTATE_NOENDBR to startup_xen()
  x86/uaccess: Add ENDBR to __put_user_nocheck*()
  x86/retpoline: Add ANNOTATE_NOENDBR for retpolines
  x86/static_call: Add ANNOTATE_NOENDBR to static call trampoline
  objtool: Enable unreachable warnings for CLANG LTO
  x86,objtool: Explicitly mark idtentry_body()s tail REACHABLE
  x86,objtool: Mark cpu_startup_entry() __noreturn
  x86,xen,objtool: Add UNWIND hint
  lib/strn*,objtool: Enforce user_access_begin() rules
  MAINTAINERS: Add x86 unwinding entry
  x86/unwind/orc: Recheck address range after stack info was updated
  x86/cpu: Load microcode during restore_processor_state()
  x86/cpu: Add new Alderlake and Raptorlake CPU model numbers

Pull objtool fixes from Borislav Petkov:
 "A bunch of objtool fixes to improve unwinding, sibling call detection,
  fallthrough detection and relocation handling of weak symbols when the
  toolchain strips section symbols"

* tag 'objtool_urgent_for_v5.18_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Fix code relocs vs weak symbols
  objtool: Fix type of reloc::addend
  objtool: Fix function fallthrough detection for vmlinux
  objtool: Fix sibling call detection in alternatives
  objtool: Don't set 'jump_dest' for sibling calls
  x86/uaccess: Don't jump between functions

Pull irq fix from Borislav Petkov:

 - Fix locking when accessing device MSI descriptors

* tag 'irq_urgent_for_v5.18_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  bus: fsl-mc-msi: Fix MSI descriptor mutex lock for msi_first_desc()

Merge tag 'driver-core-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg KH:
 "Here are some small driver core and kernfs fixes for some reported
  problems. They include:

   - kernfs regression that is causing oopses in 5.17 and newer releases

   - topology sysfs fixes for a few small reported problems.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  kernfs: fix NULL dereferencing in kernfs_remove
  topology: Fix up build warning in topology_is_visible()
  arch_topology: Do not set llc_sibling if llc_id is invalid
  topology: make core_mask include at least cluster_siblings
  topology/sysfs: Hide PPIN on systems that do not support it.

Pull char/misc driver fixes from Greg KH:
 "Here are a small number of char/misc/other driver fixes for 5.18-rc5

  Nothing major in here, this is mostly IIO driver fixes along with some
  other small things:

   - at25 driver fix for systems without a dma-able stack

   - phy driver fixes for reported issues

   - binder driver fixes for reported issues

  All of these have been in linux-next without any reported problems"

* tag 'char-misc-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (31 commits)
  eeprom: at25: Use DMA safe buffers
  binder: Gracefully handle BINDER_TYPE_FDA objects with num_fds=0
  binder: Address corner cases in deferred copy and fixup
  phy: amlogic: fix error path in phy_g12a_usb3_pcie_probe()
  iio: imu: inv_icm42600: Fix I2C init possible nack
  iio: dac: ltc2688: fix voltage scale read
  interconnect: qcom: sdx55: Drop IP0 interconnects
  interconnect: qcom: sc7180: Drop IP0 interconnects
  phy: ti: Add missing pm_runtime_disable() in serdes_am654_probe
  phy: mapphone-mdm6600: Fix PM error handling in phy_mdm6600_probe
  phy: ti: omap-usb2: Fix error handling in omap_usb2_enable_clocks
  bus: mhi: host: pci_generic: Flush recovery worker during freeze
  bus: mhi: host: pci_generic: Add missing poweroff() PM callback
  phy: ti: tusb1210: Fix an error handling path in tusb1210_probe()
  phy: samsung: exynos5250-sata: fix missing device put in probe error paths
  phy: samsung: Fix missing of_node_put() in exynos_sata_phy_probe
  phy: ti: Fix missing of_node_put in ti_pipe3_get_sysctrl()
  phy: ti: tusb1210: Make tusb1210_chg_det_states static
  iio:dac:ad3552r: Fix an IS_ERR() vs NULL check
  iio: sx9324: Fix default precharge internal resistance register
  ...

Pull tty/serial fixes from Greg KH:
 "Here are some small serial driver fixes, and a larger number of GSM
  line discipline fixes for 5.18-rc5.

  These include:

   - lots of tiny n_gsm fixes for issues to resolve a number of reported
     problems. Seems that people are starting to actually use this code
     again.

   - 8250 driver fixes for some devices

   - imx serial driver fix

   - amba-pl011 driver fix

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (27 commits)
  tty: n_gsm: fix sometimes uninitialized warning in gsm_dlci_modem_output()
  serial: 8250: Correct the clock for EndRun PTP/1588 PCIe device
  serial: 8250: Also set sticky MCR bits in console restoration
  tty: n_gsm: fix software flow control handling
  tty: n_gsm: fix invalid use of MSC in advanced option
  tty: n_gsm: fix broken virtual tty handling
  Revert "serial: sc16is7xx: Clear RS485 bits in the shutdown"
  tty: n_gsm: fix missing update of modem controls after DLCI open
  serial: 8250: Fix runtime PM for start_tx() for empty buffer
  serial: imx: fix overrun interrupts in DMA mode
  serial: amba-pl011: do not time out prematurely when draining tx fifo
  tty: n_gsm: fix incorrect UA handling
  tty: n_gsm: fix reset fifo race condition
  tty: n_gsm: fix missing tty wakeup in convergence layer type 2
  tty: n_gsm: fix wrong signal octets encoding in MSC
  tty: n_gsm: fix wrong command frame length field encoding
  tty: n_gsm: fix wrong command retry handling
  tty: n_gsm: fix missing explicit ldisc flush
  tty: n_gsm: fix wrong DLCI release order
  tty: n_gsm: fix insufficient txframe size
  ...

Pull USB fixes from Greg KH:
 "Here are a number of small USB driver fixes for 5.18-rc5 for some
  reported issues and new quirks. They include:

   - dwc3 driver fixes

   - xhci driver fixes

   - typec driver fixes

   - new usb-serial driver ids

   - added new USB devices to existing quirk tables

   - other tiny fixes

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'usb-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (31 commits)
  usb: phy: generic: Get the vbus supply
  usb: dwc3: gadget: Return proper request status
  usb: dwc3: pci: add support for the Intel Meteor Lake-P
  usb: dwc3: core: Only handle soft-reset in DCTL
  usb: gadget: configfs: clear deactivation flag in configfs_composite_unbind()
  usb: misc: eud: Fix an error handling path in eud_probe()
  usb: core: Don't hold the device lock while sleeping in do_proc_control()
  usb: dwc3: Try usb-role-switch first in dwc3_drd_init
  usb: dwc3: core: Fix tx/rx threshold settings
  usb: mtu3: fix USB 3.0 dual-role-switch from device to host
  xhci: Enable runtime PM on second Alderlake controller
  usb: dwc3: fix backwards compat with rockchip devices
  dt-bindings: usb: samsung,exynos-usb2: add missing required reg
  usb: misc: fix improper handling of refcount in uss720_probe()
  USB: Fix ehci infinite suspend-resume loop issue in zhaoxin
  usb: typec: tcpm: Fix undefined behavior due to shift overflowing the constant
  usb: typec: rt1719: Fix build error without CONFIG_POWER_SUPPLY
  usb: typec: ucsi: Fix role swapping
  usb: typec: ucsi: Fix reuse of completion structure
  usb: xhci: tegra:Fix PM usage reference leak of tegra_xusb_unpowergate_partitions
  ...