* kvm-arm64/selftests-6.12:
  : .
  : KVM/arm64 selftest updates for 6.12
  :
  : - Check for a bunch of timer emulation corner cases (COlton Lewis)
  : .
  KVM: arm64: selftests: Add arch_timer_edge_cases selftest
  KVM: arm64: selftests: Ensure pending interrupts are handled in arch_timer test
Signed-off-by: Marc Zyngier <maz@kernel.org>

* kvm-arm64/vgic-sre-traps:
  : .
  : Fix the multiple of cases where KVM/arm64 doesn't correctly
  : handle the guest trying to use a GICv3 that isn't advertised.
  :
  : From the cover letter:
  :
  : "It recently appeared that, when running on a GICv3-equipped platform
  : (which is what non-ancient arm64 HW has), *not* configuring a GICv3
  : for the guest could result in less than desirable outcomes.
  :
  : We have multiple issues to fix:
  :
  : - for registers that *always* trap (the SGI registers) or that *may*
  :   trap (the SRE register), we need to check whether a GICv3 has been
  :   instantiated before acting upon the trap.
  :
  : - for registers that only conditionally trap, we must actively trap
  :   them even in the absence of a GICv3 being instantiated, and handle
  :   those traps accordingly.
  :
  : - finally, ID registers must reflect the absence of a GICv3, so that
  :   we are consistent.
  :
  : This series goes through all these requirements. The main complexity
  : here is to apply a GICv3 configuration on the host in the absence of a
  : GICv3 in the guest. This is pretty hackish, but I don't have a much
  : better solution so far.
  :
  : As part of making wider use of of the trap bits, we fully define the
  : trap routing as per the architecture, something that we eventually
  : need for NV anyway."
  : .
  KVM: arm64: selftests: Cope with lack of GICv3 in set_id_regs
  KVM: arm64: Add selftest checking how the absence of GICv3 is handled
  KVM: arm64: Unify UNDEF injection helpers
  KVM: arm64: Make most GICv3 accesses UNDEF if they trap
  KVM: arm64: Honor guest requested traps in GICv3 emulation
  KVM: arm64: Add trap routing information for ICH_HCR_EL2
  KVM: arm64: Add ICH_HCR_EL2 to the vcpu state
  KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is presented to the guest
  KVM: arm64: Add helper for last ditch idreg adjustments
  KVM: arm64: Force GICv3 trap activation when no irqchip is configured on VHE
  KVM: arm64: Force SRE traps when SRE access is not enabled
  KVM: arm64: Move GICv3 trap configuration to kvm_calculate_traps()
Signed-off-by: Marc Zyngier <maz@kernel.org>

* kvm-arm64/fpmr:
  : .
  : Add FP8 support to the KVM/arm64 floating point handling.
  :
  : This includes new ID registers (ID_AA64PFR2_EL1 ID_AA64FPFR0_EL1)
  : being made visible to guests, as well as a new confrol register
  : (FPMR) which gets context-switched.
  : .
  KVM: arm64: Expose ID_AA64PFR2_EL1 to userspace and guests
  KVM: arm64: Enable FP8 support when available and configured
  KVM: arm64: Expose ID_AA64FPFR0_EL1 as a writable ID reg
  KVM: arm64: Honor trap routing for FPMR
  KVM: arm64: Add save/restore support for FPMR
  KVM: arm64: Move FPMR into the sysreg array
  KVM: arm64: Add predicate for FPMR support in a VM
  KVM: arm64: Move SVCR into the sysreg array
Signed-off-by: Marc Zyngier <maz@kernel.org>

* kvm-arm64/mmu-misc-6.12:
  : .
  : Various minor MMU improvements and bug-fixes:
  :
  : - Prevent MTE tags being restored by userspace if we are actively
  :   logging writes, as that's a recipe for disaster
  :
  : - Correct the refcount on a page that is not considered for MTE
  :   tag copying (such as a device)
  :
  : - When walking a page table to split blocks, keep the DSB at the end
  :   the walk, as there is no need to perform it on every store.
  :
  : - Fix boundary check when transfering memory using FFA
  : .
  KVM: arm64: Add memory length checks and remove inline in do_ffa_mem_xfer
  KVM: arm64: Disallow copying MTE to guest memory while KVM is dirty logging
  KVM: arm64: Release pfn, i.e. put page, if copying MTE tags hits ZONE_DEVICE
  KVM: arm64: Move data barrier to end of split walk
Signed-off-by: Marc Zyngier <maz@kernel.org>

When we share memory through FF-A and the description of the buffers
exceeds the size of the mapped buffer, the fragmentation API is used.
The fragmentation API allows specifying chunks of descriptors in subsequent
FF-A fragment calls and no upper limit has been established for this.
The entire memory region transferred is identified by a handle which can be
used to reclaim the transferred memory.
To be able to reclaim the memory, the description of the buffers has to fit
in the ffa_desc_buf.
Add a bounds check on the FF-A sharing path to prevent the memory reclaim
from failing.

Also do_ffa_mem_xfer() does not need __always_inline, except for the
BUILD_BUG_ON() aspect, which gets moved to a macro.

[maz: fixed the BUILD_BUG_ON() breakage with LLVM, thanks to Wei-Lin Chang
 for the timely report]

Fixes: 634d90cf ("KVM: arm64: Handle FFA_MEM_LEND calls from the host")
Cc: stable@vger.kernel.org
Reviewed-by: Sebastian Ene <sebastianene@google.com>
Signed-off-by: Snehal Koukuntla <snehalreddy@google.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240909180154.3267939-1-snehalreddy@google.comSigned-off-by: Marc Zyngier <maz@kernel.org>

Add a new arch_timer_edge_cases selftests that validates:

* timers above the max TVAL value
* timers in the past
* moving counters ahead and behind pending timers
* reprograming timers
* timers fired multiple times
* masking/unmasking using the timer control mask

These are intentionally unusual scenarios to stress compliance with
the arm architecture.
Co-developed-by: Ricardo Koller <ricarkol@google.com>
Signed-off-by: Ricardo Koller <ricarkol@google.com>
Signed-off-by: Colton Lewis <coltonlewis@google.com>
Link: https://lore.kernel.org/r/20240823175836.2798235-3-coltonlewis@google.comSigned-off-by: Marc Zyngier <maz@kernel.org>

Break up the asm instructions poking daifclr and daifset to handle
interrupts. R_RBZYL specifies pending interrupts will be handle after
context synchronization events such as an ISB.

Introduce a function wrapper for the WFI instruction.
Signed-off-by: Colton Lewis <coltonlewis@google.com>
Link: https://lore.kernel.org/r/20240823175836.2798235-2-coltonlewis@google.comSigned-off-by: Marc Zyngier <maz@kernel.org>

Broonie reports that the set_id_regs test is failing as of commit
5cb57a1a ("KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is
presented to the guest"). The test does not anticipate the 'late' ID
register fixup where KVM clobbers the GIC field in absence of GICv3.

While the field technically has FTR_LOWER_SAFE behavior, fix the issue
by setting it to an exact value of 0, matching the effect of the 'late'
fixup.
Reported-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240829004622.3058639-1-oliver.upton@linux.devSigned-off-by: Marc Zyngier <maz@kernel.org>

Given how tortuous and fragile the whole lack-of-GICv3 story is,
add a selftest checking that we don't regress it.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-12-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

We currently have two helpers (undef_access() and trap_undef()) that
do exactly the same thing: inject an UNDEF and return 'false' (as an
indication that PC should not be incremented).

We definitely could do with one less. Given that undef_access() is
used 80ish times, while trap_undef() is only used 30 times, the
latter loses the battle and is immediately sacrificed.

We also have a large number of instances where undef_access() is
open-coded. Let's also convert those.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-11-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

We don't expect to trap any GICv3 register for host handling,
apart from ICC_SRE_EL1 and the SGI registers. If they trap,
that's because the guest is playing with us despite being
told it doesn't have a GICv3.

If it does, UNDEF is what it will get.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-10-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

On platforms that require emulation of the CPU interface, we still
need to honor the traps requested by the guest (ICH_HCR_EL2 as well
as the FGTs for ICC_IGRPEN{0,1}_EL1.

Check for these bits early and lail out if any trap applies.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-9-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

The usual song and dance. Anything that is a trap, any register
it traps. Note that we don't handle the registers added by
FEAT_NMI for now.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-8-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

As we are about to describe the trap routing for ICH_HCR_EL2, add
the register to the vcpu state in its VNCR form, as well as reset
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-7-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

In order to be consistent, we shouldn't advertise a GICv3 when none
is actually usable by the guest.

Wipe the feature when these conditions apply, and allow the field
to be written from userspace.

This now allows us to rewrite the kvm_has_gicv3 helper() in terms
of kvm_has_feat(), given that it is always evaluated at runtime.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-6-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

We already have to perform a set of last-chance adjustments for
NV purposes. We will soon have to do the same for the GIC, so
introduce a helper for that exact purpose.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-5-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

On a VHE system, no GICv3 traps get configured when no irqchip is
present. This is not quite matching the "no GICv3" semantics that
we want to present.

Force such traps to be configured in this case.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-4-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

We so far only write the ICH_HCR_EL2 config in two situations:

- when we need to emulate the GICv3 CPU interface due to HW bugs

- when we do direct injection, as the virtual CPU interface needs
  to be enabled

This is all good. But it also means that we don't do anything special
when we emulate a GICv2, or that there is no GIC at all.

What happens in this case when the guest uses the GICv3 system
registers? The *guest* gets a trap for a sysreg access (EC=0x18)
while we'd really like it to get an UNDEF.

Fixing this is a bit involved:

- we need to set all the required trap bits (TC, TALL0, TALL1, TDIR)

- for these traps to take effect, we need to (counter-intuitively)
  set ICC_SRE_EL1.SRE to 1 so that the above traps take priority.

Note that doesn't fully work when GICv2 emulation is enabled, as
we cannot set ICC_SRE_EL1.SRE to 1 (it breaks Group0 delivery as
IRQ).
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-3-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

Follow the pattern introduced with vcpu_set_hcr(), and introduce
vcpu_set_ich_hcr(), which configures the GICv3 traps at the same
point.

This will allow future changes to introduce trap configuration on
a per-VM basis.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-2-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

* kvm-arm64/tlbi-fixes-6.12:
  : .
  : A couple of TLB invalidation fixes, only affecting pKVM
  : out of tree, courtesy of Will Deacon.
  : .
  KVM: arm64: Ensure TLBI uses correct VMID after changing context
  KVM: arm64: Invalidate EL1&0 TLB entries for all VMIDs in nvhe hyp init
Signed-off-by: Marc Zyngier <maz@kernel.org>

Everything is now in place for a guest to "enjoy" FP8 support.
Expose ID_AA64PFR2_EL1 to both userspace and guests, with the
explicit restriction of only being able to clear FPMR.

All other features (MTE* at the time of writing) are hidden
and not writable.
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240820131802.3547589-9-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

If userspace has enabled FP8 support (by setting ID_AA64PFR2_EL1.FPMR
to 1), let's enable the feature by setting HCRX_EL2.EnFPM for the vcpu.
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240820131802.3547589-8-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

ID_AA64FPFR0_EL1 contains all sort of bits that contain a description
of which FP8 subfeatures are implemented.

We don't really care about them, so let's just expose that register
and allow userspace to disable subfeatures at will.
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240820131802.3547589-7-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

HCRX_EL2.EnFPM controls the trapping of FPMR (as well as the validity
of any FP8 instruction, but we don't really care about this last part).

Describe the trap bit so that the exception can be reinjected in a
NV guest.
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240820131802.3547589-6-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

Just like the rest of the FP/SIMD state, FPMR needs to be context
switched.

The only interesting thing here is that we need to treat the pKVM
part a bit differently, as the host FP state is never written back
to the vcpu thread, but instead stored locally and eagerly restored.
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240820131802.3547589-5-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

Just like SVCR, FPMR is currently stored at the wrong location.

Let's move it where it belongs.
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240820131802.3547589-4-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

As we are about to check for the advertisement of FPMR support to
a guest in a number of places, add a predicate that will gate most
of the support code for FPMR.
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240820131802.3547589-3-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

SVCR is just a system register, and has no purpose being outside
of the sysreg array. If anything, it only makes it more difficult
to eventually support SME one day. If ever.

Move it into the array with its little friends, and associate it
with a visibility predicate.

Although this is dead code, it at least paves the way for the
next set of FP-related extensions.
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240820131802.3547589-2-maz@kernel.orgSigned-off-by: Marc Zyngier <maz@kernel.org>

Pull bcachefs fixes from Kent Overstreet:

 - assorted syzbot fixes

 - some upgrade fixes for old (pre 1.0) filesystems

 - fix for moving data off a device that was switched to durability=0
   after data had been written to it.

 - nocow deadlock fix

 - fix for new rebalance_work accounting

* tag 'bcachefs-2024-08-24' of git://evilpiepirate.org/bcachefs: (28 commits)
  bcachefs: Fix rebalance_work accounting
  bcachefs: Fix failure to flush moves before sleeping in copygc
  bcachefs: don't use rht_bucket() in btree_key_cache_scan()
  bcachefs: add missing inode_walker_exit()
  bcachefs: clear path->should_be_locked in bch2_btree_key_cache_drop()
  bcachefs: Fix double assignment in check_dirent_to_subvol()
  bcachefs: Fix refcounting in discard path
  bcachefs: Fix compat issue with old alloc_v4 keys
  bcachefs: Fix warning in bch2_fs_journal_stop()
  fs/super.c: improve get_tree() error message
  bcachefs: Fix missing validation in bch2_sb_journal_v2_validate()
  bcachefs: Fix replay_now_at() assert
  bcachefs: Fix locking in bch2_ioc_setlabel()
  bcachefs: fix failure to relock in btree_node_fill()
  bcachefs: fix failure to relock in bch2_btree_node_mem_alloc()
  bcachefs: unlock_long() before resort in journal replay
  bcachefs: fix missing bch2_err_str()
  bcachefs: fix time_stats_to_text()
  bcachefs: Fix bch2_bucket_gens_init()
  bcachefs: Fix bch2_trigger_alloc assert
  ...

Pull smb server fixes from Steve French:

 - query directory flex array fix

 - fix potential null ptr reference in open

 - fix error message in some open cases

 - two minor cleanups

* tag '6.11-rc5-server-fixes' of git://git.samba.org/ksmbd:
  smb/server: update misguided comment of smb2_allocate_rsp_buf()
  smb/server: remove useless assignment of 'file_present' in smb2_open()
  smb/server: fix potential null-ptr-deref of lease_ctx_info in smb2_open()
  smb/server: fix return value of smb2_open()
  ksmbd: the buffer of smb2 query dir response has at least 1 byte

Pull s390 fixes from Vasily Gorbik:

 - Fix KASLR base offset to account for symbol offsets in the vmlinux
   ELF file, preventing tool breakages like the drgn debugger

 - Fix potential memory corruption of physmem_info during kernel
   physical address randomization

 - Fix potential memory corruption due to overlap between the relocated
   lowcore and identity mapping by correctly reserving lowcore memory

 - Fix performance regression and avoid randomizing identity mapping
   base by default

 - Fix unnecessary delay of AP bus binding complete uevent to prevent
   startup lag in KVM guests using AP

* tag 's390-6.11-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/boot: Fix KASLR base offset off by __START_KERNEL bytes
  s390/boot: Avoid possible physmem_info segment corruption
  s390/ap: Refine AP bus bindings complete processing
  s390/mm: Pin identity mapping base to zero
  s390/mm: Prevent lowcore vs identity mapping overlap

Pull SCSI fixes from James Bottomley:
 "The important core fix is another tweak to our discard discovery
  issues. The off by 512 in logical block count seems bad, but in fact
  the inline was only ever used in debug prints, which is why no-one
  noticed"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: sd: Do not attempt to configure discard unless LBPME is set
  scsi: MAINTAINERS: Add header files to SCSI SUBSYSTEM
  scsi: ufs: qcom: Add UFSHCD_QUIRK_BROKEN_LSDBS_CAP for SM8550 SoC
  scsi: ufs: core: Add a quirk for handling broken LSDBS field in controller capabilities register
  scsi: core: Fix the return value of scsi_logical_block_count()
  scsi: MAINTAINERS: Update HiSilicon SAS controller driver maintainer

rebalance_work was keying off of the presence of rebelance_opts in the
extent - but that was incorrect, we keep those around after rebalance
for indirect extents since the inode's options are not directly
available

Fixes: 20ac515a ("bcachefs: bch_acct_rebalance_work")
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This fixes an apparent deadlock - rebalance would get stuck trying to
take nocow locks because they weren't being released by copygc.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Pull cgroup fixes from Tejun Heo:
 "Three patches addressing cpuset corner cases"

* tag 'cgroup-for-6.11-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup/cpuset: Eliminate unncessary sched domains rebuilds in hotplug
  cgroup/cpuset: Clear effective_xcpus on cpus_allowed clearing only if cpus.exclusive not set
  cgroup/cpuset: fix panic caused by partcmd_update

Pull workqueue fixes from Tejun Heo:
 "Nothing too interesting. One patch to remove spurious warning and
  others to address static checker warnings"

* tag 'wq-for-6.11-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Correct declaration of cpu_pwq in struct workqueue_struct
  workqueue: Fix spruious data race in __flush_work()
  workqueue: Remove incorrect "WARN_ON_ONCE(!list_empty(&worker->entry));" from dying worker
  workqueue: Fix UBSAN 'subtraction overflow' error in shift_and_mask()
  workqueue: doc: Fix function name, remove markers

Pull MIPS fixes from Thomas Bogendoerfer:

 - Set correct timer mode on Loongson64

 - Only request r4k clockevent interrupt on one CPU

* tag 'mips-fixes_6.11_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: cevt-r4k: Don't call get_c0_compare_int if timer irq is installed
  MIPS: Loongson64: Set timer mode in cpu-probe

Pull arm64 kvm fixes from Catalin Marinas:

 - Don't drop references on LPIs that weren't visited by the vgic-debug
   iterator

 - Cure lock ordering issue when unregistering vgic redistributors

 - Fix for misaligned stage-2 mappings when VMs are backed by hugetlb
   pages

 - Treat SGI registers as UNDEFINED if a VM hasn't been configured for
   GICv3

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  KVM: arm64: Make ICC_*SGI*_EL1 undef in the absence of a vGICv3
  KVM: arm64: Ensure canonical IPA is hugepage-aligned when handling fault
  KVM: arm64: vgic: Don't hold config_lock while unregistering redistributors
  KVM: arm64: vgic-debug: Don't put unmarked LPIs

Pull NFS client fixes from Anna Schumaker:

 - Fix rpcrdma refcounting in xa_alloc

 - Fix rpcrdma usage of XA_FLAGS_ALLOC

 - Fix requesting FATTR4_WORD2_OPEN_ARGUMENTS

 - Fix attribute bitmap decoder to handle a 3rd word

 - Add reschedule points when returning delegations to avoid soft lockups

 - Fix clearing layout segments in layoutreturn

 - Avoid unnecessary rescanning of the per-server delegation list

* tag 'nfs-for-6.11-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  NFS: Avoid unnecessary rescanning of the per-server delegation list
  NFSv4: Fix clearing of layout segments in layoutreturn
  NFSv4: Add missing rescheduling points in nfs_client_return_marked_delegations
  nfs: fix bitmap decoder to handle a 3rd word
  nfs: fix the fetch of FATTR4_OPEN_ARGUMENTS
  rpcrdma: Trace connection registration and unregistration
  rpcrdma: Use XA_FLAGS_ALLOC instead of XA_FLAGS_ALLOC1
  rpcrdma: Device kref is over-incremented on error from xa_alloc