* kvm-arm64/nv-eret-pauth:
  : .
  : Add NV support for the ERETAA/ERETAB instructions. From the cover letter:
  :
  : "Although the current upstream NV support has *some* support for
  : correctly emulating ERET, that support is only partial as it doesn't
  : support the ERETAA and ERETAB variants.
  :
  : Supporting these instructions was cast aside for a long time as it
  : involves implementing some form of PAuth emulation, something I wasn't
  : overly keen on. But I have reached a point where enough of the
  : infrastructure is there that it actually makes sense. So here it is!"
  : .
  KVM: arm64: nv: Work around lack of pauth support in old toolchains
  KVM: arm64: Drop trapping of PAuth instructions/keys
  KVM: arm64: nv: Advertise support for PAuth
  KVM: arm64: nv: Handle ERETA[AB] instructions
  KVM: arm64: nv: Add emulation for ERETAx instructions
  KVM: arm64: nv: Add kvm_has_pauth() helper
  KVM: arm64: nv: Reinject PAC exceptions caused by HCR_EL2.API==0
  KVM: arm64: nv: Handle HCR_EL2.{API,APK} independently
  KVM: arm64: nv: Honor HFGITR_EL2.ERET being set
  KVM: arm64: nv: Fast-track 'InHost' exception returns
  KVM: arm64: nv: Add trap forwarding for ERET and SMC
  KVM: arm64: nv: Configure HCR_EL2 for FEAT_NV2
  KVM: arm64: nv: Drop VCPU_HYP_CONTEXT flag
  KVM: arm64: Constraint PAuth support to consistent implementations
  KVM: arm64: Add helpers for ESR_ELx_ERET_ISS_ERET*
  KVM: arm64: Harden __ctxt_sys_reg() against out-of-range values
Signed-off-by: Marc Zyngier <maz@kernel.org>

* kvm-arm64/host_data:
  : .
  : Rationalise the host-specific data to live as part of the per-CPU state.
  :
  : From the cover letter:
  :
  : "It appears that over the years, we have accumulated a lot of cruft in
  : the kvm_vcpu_arch structure. Part of the gunk is data that is strictly
  : host CPU specific, and this result in two main problems:
  :
  : - the structure itself is stupidly large, over 8kB. With the
  :   arch-agnostic kvm_vcpu, we're above 10kB, which is insane. This has
  :   some ripple effects, as we need physically contiguous allocation to
  :   be able to map it at EL2 for !VHE. There is more to it though, as
  :   some data structures, although per-vcpu, could be allocated
  :   separately.
  :
  : - We lose track of the life-cycle of this data, because we're
  :   guaranteed that it will be around forever and we start relying on
  :   wrong assumptions. This is becoming a maintenance burden.
  :
  : This series rectifies some of these things, starting with the two main
  : offenders: debug and FP, a lot of which gets pushed out to the per-CPU
  : host structure. Indeed, their lifetime really isn't that of the vcpu,
  : but tied to the physical CPU the vpcu runs on.
  :
  : This results in a small reduction of the vcpu size, but mainly a much
  : clearer understanding of the life-cycle of these structures."
  : .
  KVM: arm64: Move management of __hyp_running_vcpu to load/put on VHE
  KVM: arm64: Exclude FP ownership from kvm_vcpu_arch
  KVM: arm64: Exclude host_fpsimd_state pointer from kvm_vcpu_arch
  KVM: arm64: Exclude mdcr_el2_host from kvm_vcpu_arch
  KVM: arm64: Exclude host_debug_data from vcpu_arch
  KVM: arm64: Add accessor for per-CPU state
Signed-off-by: Marc Zyngier <maz@kernel.org>

The per-CPU host context structure contains a __hyp_running_vcpu that
serves as a replacement for kvm_get_current_vcpu() in contexts where
we cannot make direct use of it (such as in the nVHE hypervisor).
Since there is a lot of common code between nVHE and VHE, the latter
also populates this field even if kvm_get_running_vcpu() always works.

We currently pretty inconsistent when populating __hyp_running_vcpu
to point to the currently running vcpu:

- on {n,h}VHE, we set __hyp_running_vcpu on entry to __kvm_vcpu_run
  and clear it on exit.

- on VHE, we set __hyp_running_vcpu on entry to __kvm_vcpu_run_vhe
  and never clear it, effectively leaving a dangling pointer...

VHE is obviously the odd one here. Although we could make it behave
just like nVHE, this wouldn't match the behaviour of KVM with VHE,
where the load phase is where most of the context-switch gets done.

So move all the __hyp_running_vcpu management to the VHE-specific
load/put phases, giving us a bit more sanity and matching the
behaviour of kvm_get_running_vcpu().
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240502154030.3011995-1-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

We still support GCC 8.x, and it appears that this toolchain
usually comes with an assembler that does not understand "pauth"
as a valid architectural extension.

This results in the NV ERETAx code breaking the build, as it relies
on this extention to make use of the PACGA instruction (required
by assemblers such as LLVM's).

Work around it by hand-assembling the instruction, which removes the
requirement for any assembler directive.

Fixes: 6ccc971e ("KVM: arm64: nv: Add emulation for ERETAx instructions")
Reported-by: Linaro Kernel Functional Testing <lkft@linaro.org>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marc Zyngier <maz@kernel.org>

We currently insist on disabling PAuth on vcpu_load(), and get to
enable it on first guest use of an instruction or a key (ignoring
the NV case for now).

It isn't clear at all what this is trying to achieve: guests tend
to use PAuth when available, and nothing forces you to expose it
to the guest if you don't want to. This also isn't totally free:
we take a full GPR save/restore between host and guest, only to
write ten 64bit registers. The "value proposition" escapes me.

So let's forget this stuff and enable PAuth eagerly if exposed to
the guest. This results in much simpler code. Performance wise,
that's not bad either (tested on M2 Pro running a fully automated
Debian installer as the workload):

- On a non-NV guest, I can see reduction of 0.24% in the number
  of cycles (measured with perf over 10 consecutive runs)

- On a NV guest (L2), I see a 2% reduction in wall-clock time
  (measured with 'time', as M2 doesn't have a PMUv3 and NV
  doesn't support it either)

So overall, a much reduced complexity and a (small) performance
improvement.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-16-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

Now that we (hopefully) correctly handle ERETAx, drop the masking
of the PAuth feature (something that was not even complete, as
APA3 and AGA3 were still exposed).
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-15-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

Now that we have some emulation in place for ERETA[AB], we can
plug it into the exception handling machinery.

As for a bare ERET, an "easy" ERETAx instruction is processed as
a fixup, while something that requires a translation regime
transition or an exception delivery is left to the slow path.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-14-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

FEAT_NV has the interesting property of relying on ERET being
trapped. An added complexity is that it also traps ERETAA and
ERETAB, meaning that the Pointer Authentication aspect of these
instruction must be emulated.

Add an emulation of Pointer Authentication, limited to ERETAx
(always using SP_EL2 as the modifier and ELR_EL2 as the pointer),
using the Generic Authentication instructions.

The emulation, however small, is placed in its own compilation
unit so that it can be avoided if the configuration doesn't
include it (or the toolchan in not up to the task).
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-13-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

Pointer Authentication comes in many flavors, and a faithful emulation
relies on correctly handling the flavour implemented by the HW.

For this, provide a new kvm_has_pauth() that checks whether we
expose to the guest a particular level of support. This checks
across all 3 possible authentication algorithms (Q5, Q3 and IMPDEF).
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-12-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

In order for a L1 hypervisor to correctly handle PAuth instructions,
it must observe traps caused by a L1 PAuth instruction when
HCR_EL2.API==0. Since we already handle the case for API==1 as
a fixup, only the exception injection case needs to be handled.

Rework the kvm_handle_ptrauth() callback to reinject the trap
in this case. Note that APK==0 is already handled by the exising
triage_sysreg_trap() helper.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-11-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

Although KVM couples API and APK for simplicity, the architecture
makes no such requirement, and the two can be independently set or
cleared.

Check for which of the two possible reasons we have trapped here,
and if the corresponding L1 control bit isn't set, delegate the
handling for forwarding.

Otherwise, set this exact bit in HCR_EL2 and resume the guest.
Of course, in the non-NV case, we keep setting both bits and
be done with it. Note that the entry core already saves/restores
the keys should any of the two control bits be set.

This results in a bit of rework, and the removal of the (trivial)
vcpu_ptrauth_enable() helper.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-10-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

If the L1 hypervisor decides to trap ERETs while running L2,
make sure we don't try to emulate it, just like we wouldn't
if it had its NV bit set.

The exception will be reinjected from the core handler.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-9-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

A significant part of the FEAT_NV extension is to trap ERET
instructions so that the hypervisor gets a chance to switch
from a vEL2 L1 guest to an EL1 L2 guest.

But this also has the unfortunate consequence of trapping ERET
in unsuspecting circumstances, such as staying at vEL2 (interrupt
handling while being in the guest hypervisor), or returning to host
userspace in the case of a VHE guest.

Although we already make some effort to handle these ERET quicker
by not doing the put/load dance, it is still way too far down the
line for it to be efficient enough.

For these cases, it would ideal to ERET directly, no question asked.
Of course, we can't do that. But the next best thing is to do it as
early as possible, in fixup_guest_exit(), much as we would handle
FPSIMD exceptions.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-8-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

Honor the trap forwarding bits for both ERET and SMC, using a new
helper that checks for common conditions.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Co-developed-by: Jintack Lim <jintack.lim@linaro.org>
Signed-off-by: Jintack Lim <jintack.lim@linaro.org>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-7-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

Add the HCR_EL2 configuration for FEAT_NV2, adding the required
bits for running a guest hypervisor, and overall merging the
allowed bits provided by the guest.

This heavily replies on unavaliable features being sanitised
when the HCR_EL2 shadow register is accessed, and only a couple
of bits must be explicitly disabled.

Non-NV guests are completely unaffected by any of this.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-6-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

It has become obvious that HCR_EL2.NV serves the exact same use
as VCPU_HYP_CONTEXT, only in an architectural way. So just drop
the flag for good.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-5-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

PAuth comes it two parts: address authentication, and generic
authentication. So far, KVM mandates that both are implemented.

PAuth also comes in three flavours: Q5, Q3, and IMPDEF. Only one
can be implemented for any of address and generic authentication.

Crucially, the architecture doesn't mandate that address and generic
authentication implement the *same* flavour. This would make
implementing ERETAx very difficult for NV, something we are not
terribly keen on.

So only allow PAuth support for KVM on systems that are not totally
insane. Which is so far 100% of the known HW.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-4-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

The ESR_ELx_ERET_ISS_ERET* macros are a bit confusing:

- ESR_ELx_ERET_ISS_ERET really indicates that we have trapped an
  ERETA* instruction, as opposed to an ERET

- ESR_ELx_ERET_ISS_ERETA really indicates that we have trapped
  an ERETAB instruction, as opposed to an ERETAA.

We could repaint those to make more sense, but these are the
names that are present in the ARM ARM, and we are sentimentally
attached to those.

Instead, add two new helpers:

- esr_iss_is_eretax() being true tells you that you need to
  authenticate the ERET

- esr_iss_is_eretab() tells you that you need to use the B key
  instead of the A key

Following patches will make use of these primitives.
Suggested-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-3-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

The unsuspecting kernel tinkerer can be easily confused into
writing something that looks like this:

	ikey.lo = __vcpu_sys_reg(vcpu, SYS_APIAKEYLO_EL1);

which seems vaguely sensible, until you realise that the second
parameter is the encoding of a sysreg, and not the index into
the vcpu sysreg file... Debugging what happens in this case is
an interesting exercise in head<->wall interactions.

As they often say: "Any resemblance to actual persons, living
or dead, or actual events is purely coincidental".

In order to save people's time, add some compile-time hardening
that will at least weed out the "stupidly out of range" values.
This will *not* catch anything that isn't a compile-time constant.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-2-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

In retrospect, it is fairly obvious that the FP state ownership
is only meaningful for a given CPU, and that locating this
information in the vcpu was just a mistake.

Move the ownership tracking into the host data structure, and
rename it from fp_state to fp_owner, which is a better description
(name suggested by Mark Brown).
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>

As the name of the field indicates, host_fpsimd_state is strictly
a host piece of data, and we reset this pointer on each PID change.

So let's move it where it belongs, and set it at load-time. Although
this is slightly more often, it is a well defined life-cycle which
matches other pieces of data.
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>

As for the rest of the host debug state, the host copy of mdcr_el2
has little to do in the vcpu, and is better placed in the host_data
structure.

Reviewed-by : Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>

Keeping host_debug_state on a per-vcpu basis is completely
pointless. The lifetime of this data is only that of the inner
run-loop, which means it is never accessed outside of the core
EL2 code.

Move the structure into kvm_host_data, and save over 500 bytes
per vcpu.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>

In order to facilitate the introduction of new per-CPU state,
add a new host_data_ptr() helped that hides some of the per-CPU
verbosity, and make it easier to move that state around in the
future.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>

Pull x86 fixes from Ingo Molnar:

 - Fix MCE timer reinit locking

 - Fix/improve CoCo guest random entropy pool init

 - Fix SEV-SNP late disable bugs

 - Fix false positive objtool build warning

 - Fix header dependency bug

 - Fix resctrl CPU offlining bug

* tag 'x86-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/retpoline: Add NOENDBR annotation to the SRSO dummy return thunk
  x86/mce: Make sure to grab mce_sysfs_mutex in set_bank()
  x86/CPU/AMD: Track SNP host status with cc_platform_*()
  x86/cc: Add cc_platform_set/_clear() helpers
  x86/kvm/Kconfig: Have KVM_AMD_SEV select ARCH_HAS_CC_PLATFORM
  x86/coco: Require seeding RNG with RDRAND on CoCo systems
  x86/numa/32: Include missing <asm/pgtable_areas.h>
  x86/resctrl: Fix uninitialized memory read when last CPU of domain goes offline

Pull timer fixes from Ingo Molnar:
 "Fix various timer bugs:

   - Fix a timer migration bug that may result in missed events

   - Fix timer migration group hierarchy event updates

   - Fix a PowerPC64 build warning

   - Fix a handful of DocBook annotation bugs"

* tag 'timers-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timers/migration: Return early on deactivation
  timers/migration: Fix ignored event due to missing CPU update
  vdso: Use CONFIG_PAGE_SHIFT in vdso/datapage.h
  timers: Fix text inconsistencies and spelling
  tick/sched: Fix struct tick_sched doc warnings
  tick/sched: Fix various kernel-doc warnings
  timers: Fix kernel-doc format and add Return values
  time/timekeeping: Fix kernel-doc warnings and typos
  time/timecounter: Fix inline documentation

Pull x86 perf fix from Ingo Molnar:
 "Fix a combined PEBS events bug on x86 Intel CPUs"

* tag 'perf-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/ds: Don't clear ->pebs_data_cfg for the last PEBS event

Pull nfsd fixes from Chuck Lever:

 - Address a slow memory leak with RPC-over-TCP

 - Prevent another NFS4ERR_DELAY loop during CREATE_SESSION

* tag 'nfsd-6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  nfsd: hold a lighter-weight client reference over CB_RECALL_ANY
  SUNRPC: Fix a slow server-side memory leak with RPC-over-TCP

Pull i2c fix from Wolfram Sang:
 "A host driver build fix"

* tag 'i2c-for-6.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: pxa: hide unused icr_bits[] variable

Pull xfs fix from Chandan Babu:

 - Allow creating new links to special files which were not associated
   with a project quota

* tag 'xfs-6.9-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: allow cross-linking special files without project quota

Pull smb client fixes from Steve French:

 - fix to retry close to avoid potential handle leaks when server
   returns EBUSY

 - DFS fixes including a fix for potential use after free

 - fscache fix

 - minor strncpy cleanup

 - reconnect race fix

 - deal with various possible UAF race conditions tearing sessions down

* tag '6.9-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb: client: fix potential UAF in cifs_signal_cifsd_for_reconnect()
  smb: client: fix potential UAF in smb2_is_network_name_deleted()
  smb: client: fix potential UAF in is_valid_oplock_break()
  smb: client: fix potential UAF in smb2_is_valid_oplock_break()
  smb: client: fix potential UAF in smb2_is_valid_lease_break()
  smb: client: fix potential UAF in cifs_stats_proc_show()
  smb: client: fix potential UAF in cifs_stats_proc_write()
  smb: client: fix potential UAF in cifs_dump_full_key()
  smb: client: fix potential UAF in cifs_debug_files_proc_show()
  smb3: retrying on failed server close
  smb: client: serialise cifs_construct_tcon() with cifs_mount_mutex
  smb: client: handle DFS tcons in cifs_construct_tcon()
  smb: client: refresh referral without acquiring refpath_lock
  smb: client: guarantee refcounted children from parent session
  cifs: Fix caching to try to do open O_WRONLY as rdwr on server
  smb: client: fix UAF in smb2_reconnect_server()
  smb: client: replace deprecated strncpy with strscpy

srso_alias_untrain_ret() is special code, even if it is a dummy
which is called in the !SRSO case, so annotate it like its real
counterpart, to address the following objtool splat:

  vmlinux.o: warning: objtool: .export_symbol+0x2b290: data relocation to !ENDBR: srso_alias_untrain_ret+0x0

Fixes: 4535e1a4 ("x86/bugs: Fix the SRSO mitigation on Zen3/4")
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20240405144637.17908-1-bp@kernel.org

We want to fix:

  0e110732 ("x86/retpoline: Do the necessary fixup to the Zen3/4 srso return thunk for !SRSO")

So merge in Linus's latest into x86/urgent to have it available.
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'i2c-host-fixes-6.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux into i2c/for-current

An unused const variable kind of error has been fixed by placing
the definition of icr_bits[] inside the ifdef block where it is
used.

Merge tag 'firewire-fixes-6.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394

Pull firewire fixes from Takashi Sakamoto:
 "The firewire-ohci kernel module has a parameter for verbose kernel
  logging. It is well-known that it logs the spurious IRQ for bus-reset
  event due to the unmasked register for IRQ event. This update fixes
  the issue"

* tag 'firewire-fixes-6.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
  firewire: ohci: mask bus reset interrupts between ISR and bottom half

In the FireWire OHCI interrupt handler, if a bus reset interrupt has
occurred, mask bus reset interrupts until bus_reset_work has serviced and
cleared the interrupt.

Normally, we always leave bus reset interrupts masked. We infer the bus
reset from the self-ID interrupt that happens shortly thereafter. A
scenario where we unmask bus reset interrupts was introduced in 2008 in
a007bb85: If
OHCI_PARAM_DEBUG_BUSRESETS (8) is set in the debug parameter bitmask, we
will unmask bus reset interrupts so we can log them.

irq_handler logs the bus reset interrupt. However, we can't clear the bus
reset event flag in irq_handler, because we won't service the event until
later. irq_handler exits with the event flag still set. If the
corresponding interrupt is still unmasked, the first bus reset will
usually freeze the system due to irq_handler being called again each
time it exits. This freeze can be reproduced by loading firewire_ohci
with "modprobe firewire_ohci debug=-1" (to enable all debugging output).
Apparently there are also some cases where bus_reset_work will get called
soon enough to clear the event, and operation will continue normally.

This freeze was first reported a few months after a007bb85 was committed,
but until now it was never fixed. The debug level could safely be set
to -1 through sysfs after the module was loaded, but this would be
ineffectual in logging bus reset interrupts since they were only
unmasked during initialization.

irq_handler will now leave the event flag set but mask bus reset
interrupts, so irq_handler won't be called again and there will be no
freeze. If OHCI_PARAM_DEBUG_BUSRESETS is enabled, bus_reset_work will
unmask the interrupt after servicing the event, so future interrupts
will be caught as desired.

As a side effect to this change, OHCI_PARAM_DEBUG_BUSRESETS can now be
enabled through sysfs in addition to during initial module loading.
However, when enabled through sysfs, logging of bus reset interrupts will
be effective only starting with the second bus reset, after
bus_reset_work has executed.
Signed-off-by: Adam Goldman <adamg@pobox.com>
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>

Pull spi fixes from Mark Brown:
 "A few small driver specific fixes, the most important being the
  s3c64xx change which is likely to be hit during normal operation"

* tag 'spi-fix-v6.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: mchp-pci1xxx: Fix a possible null pointer dereference in pci1xxx_spi_probe
  spi: spi-fsl-lpspi: remove redundant spi_controller_put call
  spi: s3c64xx: Use DMA mode from fifo size

Merge tag 'regulator-fix-v6.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator

Pull regulator fix from Mark Brown:
 "One simple regualtor fix, fixing module autoloading on tps65132"

* tag 'regulator-fix-v6.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: tps65132: Add of_match table

Pull regmap fixes from Mark Brown:
 "Richard found a nasty corner case in the maple tree code which he
  fixed, and also fixed a compiler warning which was showing up with the
  toolchain he uses and helpfully identified a possible incorrect error
  code which could have runtime impacts"

* tag 'regmap-fix-v6.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: maple: Fix uninitialized symbol 'ret' warnings
  regmap: maple: Fix cache corruption in regcache_maple_drop()