As Eric reported, the 'reason' field is not presented when trace the
kfree_skb event by perf:

$ perf record -e skb:kfree_skb -a sleep 10
$ perf script
  ip_defrag 14605 [021]   221.614303:   skb:kfree_skb:
  skbaddr=0xffff9d2851242700 protocol=34525 location=0xffffffffa39346b1
  reason:

The cause seems to be passing kernel address directly to TP_printk(),
which is not right. As the enum 'skb_drop_reason' is not exported to
user space through TRACE_DEFINE_ENUM(), perf can't get the drop reason
string from the 'reason' field, which is a number.

Therefore, we introduce the macro DEFINE_DROP_REASON(), which is used
to define the trace enum by TRACE_DEFINE_ENUM(). With the help of
DEFINE_DROP_REASON(), now we can remove the auto-generate that we
introduced in the commit ec43908dd556
("net: skb: use auto-generation to convert skb drop reason to string"),
and define the string array 'drop_reasons'.

Hmmmm...now we come back to the situation that have to maintain drop
reasons in both enum skb_drop_reason and DEFINE_DROP_REASON. But they
are both in dropreason.h, which makes it easier.

After this commit, now the format of kfree_skb is like this:

$ cat /tracing/events/skb/kfree_skb/format
name: kfree_skb
ID: 1524
format:
        field:unsigned short common_type;       offset:0;       size:2; signed:0;
        field:unsigned char common_flags;       offset:2;       size:1; signed:0;
        field:unsigned char common_preempt_count;       offset:3;       size:1; signed:0;
        field:int common_pid;   offset:4;       size:4; signed:1;

        field:void * skbaddr;   offset:8;       size:8; signed:0;
        field:void * location;  offset:16;      size:8; signed:0;
        field:unsigned short protocol;  offset:24;      size:2; signed:0;
        field:enum skb_drop_reason reason;      offset:28;      size:4; signed:0;

print fmt: "skbaddr=%p protocol=%u location=%p reason: %s", REC->skbaddr, REC->protocol, REC->location, __print_symbolic(REC->reason, { 1, "NOT_SPECIFIED" }, { 2, "NO_SOCKET" } ......

Fixes: ec43908dd556 ("net: skb: use auto-generation to convert skb drop reason to string")
Link: https://lore.kernel.org/netdev/CANn89i+bx0ybvE55iMYf5GJM48WwV1HNpdm9Q6t-HaEstqpCSA@mail.gmail.com/
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull more kvm updates from Paolo Bonzini:

 - Xen timer fixes

 - Documentation formatting fixes

 - Make rseq selftest compatible with glibc-2.35

 - Fix handling of illegal LEA reg, reg

 - Cleanup creation of debugfs entries

 - Fix steal time cache handling bug

 - Fixes for MMIO caching

 - Optimize computation of number of LBRs

 - Fix uninitialized field in guest_maxphyaddr < host_maxphyaddr path

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (26 commits)
  KVM: x86/MMU: properly format KVM_CAP_VM_DISABLE_NX_HUGE_PAGES capability table
  Documentation: KVM: extend KVM_CAP_VM_DISABLE_NX_HUGE_PAGES heading underline
  KVM: VMX: Adjust number of LBR records for PERF_CAPABILITIES at refresh
  KVM: VMX: Use proper type-safe functions for vCPU => LBRs helpers
  KVM: x86: Refresh PMU after writes to MSR_IA32_PERF_CAPABILITIES
  KVM: selftests: Test all possible "invalid" PERF_CAPABILITIES.LBR_FMT vals
  KVM: selftests: Use getcpu() instead of sched_getcpu() in rseq_test
  KVM: selftests: Make rseq compatible with glibc-2.35
  KVM: Actually create debugfs in kvm_create_vm()
  KVM: Pass the name of the VM fd to kvm_create_vm_debugfs()
  KVM: Get an fd before creating the VM
  KVM: Shove vcpu stats_id init into kvm_vcpu_init()
  KVM: Shove vm stats_id init into kvm_create_vm()
  KVM: x86/mmu: Add sanity check that MMIO SPTE mask doesn't overlap gen
  KVM: x86/mmu: rename trace function name for asynchronous page fault
  KVM: x86/xen: Stop Xen timer before changing IRQ
  KVM: x86/xen: Initialize Xen timer only once
  KVM: SVM: Disable SEV-ES support if MMIO caching is disable
  KVM: x86/mmu: Fully re-evaluate MMIO caching when SPTE masks change
  KVM: x86: Tag kvm_mmu_x86_module_init() with __init
  ...

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Stable fixes:
   - pNFS/flexfiles: Fix infinite looping when the RDMA connection
     errors out

  Bugfixes:
   - NFS: fix port value parsing
   - SUNRPC: Reinitialise the backchannel request buffers before reuse
   - SUNRPC: fix expiry of auth creds
   - NFSv4: Fix races in the legacy idmapper upcall
   - NFS: O_DIRECT fixes from Jeff Layton
   - NFSv4.1: Fix OP_SEQUENCE error handling
   - SUNRPC: Fix an RPC/RDMA performance regression
   - NFS: Fix case insensitive renames
   - NFSv4/pnfs: Fix a use-after-free bug in open
   - NFSv4.1: RECLAIM_COMPLETE must handle EACCES

  Features:
   - NFSv4.1: session trunking enhancements
   - NFSv4.2: READ_PLUS performance optimisations
   - NFS: relax the rules for rsize/wsize mount options
   - NFS: don't unhash dentry during unlink/rename
   - SUNRPC: Fail faster on bad verifier
   - NFS/SUNRPC: Various tracing improvements"

* tag 'nfs-for-5.20-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (46 commits)
  NFS: Improve readpage/writepage tracing
  NFS: Improve O_DIRECT tracing
  NFS: Improve write error tracing
  NFS: don't unhash dentry during unlink/rename
  NFSv4/pnfs: Fix a use-after-free bug in open
  NFS: nfs_async_write_reschedule_io must not recurse into the writeback code
  SUNRPC: Don't reuse bvec on retransmission of the request
  SUNRPC: Reinitialise the backchannel request buffers before reuse
  NFSv4.1: RECLAIM_COMPLETE must handle EACCES
  NFSv4.1 probe offline transports for trunking on session creation
  SUNRPC create a function that probes only offline transports
  SUNRPC export xprt_iter_rewind function
  SUNRPC restructure rpc_clnt_setup_test_and_add_xprt
  NFSv4.1 remove xprt from xprt_switch if session trunking test fails
  SUNRPC create an rpc function that allows xprt removal from rpc_clnt
  SUNRPC enable back offline transports in trunking discovery
  SUNRPC create an iterator to list only OFFLINE xprts
  NFSv4.1 offline trunkable transports on DESTROY_SESSION
  SUNRPC add function to offline remove trunkable transports
  SUNRPC expose functions for offline remote xprt functionality
  ...

Rename the tracepoint function from trace_kvm_async_pf_doublefault() to
trace_kvm_async_pf_repeated_fault() to make it clear, since double fault
has nothing to do with this trace function.

Asynchronous Page Fault (APF) is an artifact generated by KVM when it
cannot find a physical page to satisfy an EPT violation. KVM uses APF to
tell the guest OS to do something else such as scheduling other guest
processes to make forward progress. However, when another guest process
also touches a previously APFed page, KVM halts the vCPU instead of
generating a repeated APF to avoid wasting cycles.

Double fault (#DF) clearly has a different meaning and a different
consequence when triggered. #DF requires two nested contributory exceptions
instead of two page faults faulting at the same address. A prevous bug on
APF indicates that it may trigger a double fault in the guest [1] and
clearly this trace function has nothing to do with it. So rename this
function should be a valid choice.

No functional change intended.

[1] https://www.spinics.net/lists/kvm/msg214957.html

Signed-off-by: Mingwei Zhang <mizhang@google.com>
Message-Id: <20220807052141.69186-1-mizhang@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Pull nfsd updates from Chuck Lever:
 "Work on 'courteous server', which was introduced in 5.19, continues
  apace. This release introduces a more flexible limit on the number of
  NFSv4 clients that NFSD allows, now that NFSv4 clients can remain in
  courtesy state long after the lease expiration timeout. The client
  limit is adjusted based on the physical memory size of the server.

  The NFSD filecache is a cache of files held open by NFSv4 clients or
  recently touched by NFSv2 or NFSv3 clients. This cache had some
  significant scalability constraints that have been relieved in this
  release. Thanks to all who contributed to this work.

  A data corruption bug found during the most recent NFS bake-a-thon
  that involves NFSv3 and NFSv4 clients writing the same file has been
  addressed in this release.

  This release includes several improvements in CPU scalability for
  NFSv4 operations. In addition, Neil Brown provided patches that
  simplify locking during file lookup, creation, rename, and removal
  that enables subsequent work on making these operations more scalable.
  We expect to see that work materialize in the next release.

  There are also numerous single-patch fixes, clean-ups, and the usual
  improvements in observability"

* tag 'nfsd-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (78 commits)
  lockd: detect and reject lock arguments that overflow
  NFSD: discard fh_locked flag and fh_lock/fh_unlock
  NFSD: use (un)lock_inode instead of fh_(un)lock for file operations
  NFSD: use explicit lock/unlock for directory ops
  NFSD: reduce locking in nfsd_lookup()
  NFSD: only call fh_unlock() once in nfsd_link()
  NFSD: always drop directory lock in nfsd_unlink()
  NFSD: change nfsd_create()/nfsd_symlink() to unlock directory before returning.
  NFSD: add posix ACLs to struct nfsd_attrs
  NFSD: add security label to struct nfsd_attrs
  NFSD: set attributes when creating symlinks
  NFSD: introduce struct nfsd_attrs
  NFSD: verify the opened dentry after setting a delegation
  NFSD: drop fh argument from alloc_init_deleg
  NFSD: Move copy offload callback arguments into a separate structure
  NFSD: Add nfsd4_send_cb_offload()
  NFSD: Remove kmalloc from nfsd4_do_async_copy()
  NFSD: Refactor nfsd4_do_copy()
  NFSD: Refactor nfsd4_cleanup_inter_ssc() (2/2)
  NFSD: Refactor nfsd4_cleanup_inter_ssc() (1/2)
  ...

Pull fscache updates from David Howells:

 - Fix a cookie access ref leak if a cookie is invalidated a second time
   before the first invalidation is actually processed.

 - Add a tracepoint to log cookie lookup failure

* tag 'fscache-fixes-20220809' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  fscache: add tracepoint when failing cookie
  fscache: don't leak cookie access refs if invalidation is in progress or failed

Pull AFS fixes from David Howells:
 "Fix AFS refcount handling.

  The first patch converts afs to use refcount_t for its refcounts and
  the second patch fixes afs_put_call() and afs_put_server() to save the
  values they're going to log in the tracepoint before decrementing the
  refcount"

* tag 'afs-fixes-20220802' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Fix access after dec in put functions
  afs: Use refcount_t rather than atomic_t

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>

Pull more power management updates from Rafael Wysocki:
 "These are ARM cpufreq updates and operating performance points (OPP)
  updates plus one cpuidle update adding a new trace point.

  Specifics:

   - Fix return error code in mtk_cpu_dvfs_info_init (Yang Yingliang).

   - Minor cleanups and support for new boards for Qcom cpufreq drivers
     (Bryan O'Donoghue, Konrad Dybcio, Pierre Gondois, and Yicong Yang).

   - Fix sparse warnings for Tegra cpufreq driver (Viresh Kumar).

   - Make dev_pm_opp_set_regulators() accept NULL terminated list
     (Viresh Kumar).

   - Add dev_pm_opp_set_config() and friends and migrate other users and
     helpers to using them (Viresh Kumar).

   - Add support for multiple clocks for a device (Viresh Kumar and
     Krzysztof Kozlowski).

   - Configure resources before adding OPP table for Venus (Stanimir
     Varbanov).

   - Keep reference count up for opp->np and opp_table->np while they
     are still in use (Liang He).

   - Minor OPP cleanups (Viresh Kumar and Yang Li).

   - Add a trace event for cpuidle to track missed (too deep or too
     shallow) wakeups (Kajetan Puchalski)"

* tag 'pm-5.20-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (55 commits)
  cpuidle: Add cpu_idle_miss trace event
  venus: pm_helpers: Fix warning in OPP during probe
  OPP: Don't drop opp->np reference while it is still in use
  OPP: Don't drop opp_table->np reference while it is still in use
  cpufreq: tegra194: Staticize struct tegra_cpufreq_soc instances
  dt-bindings: cpufreq: cpufreq-qcom-hw: Add SM6375 compatible
  dt-bindings: opp: Add msm8939 to the compatible list
  dt-bindings: opp: Add missing compat devices
  dt-bindings: opp: opp-v2-kryo-cpu: Fix example binding checks
  cpufreq: Change order of online() CB and policy->cpus modification
  cpufreq: qcom-hw: Remove deprecated irq_set_affinity_hint() call
  cpufreq: qcom-hw: Disable LMH irq when disabling policy
  cpufreq: qcom-hw: Reset cancel_throttle when policy is re-enabled
  cpufreq: qcom-cpufreq-hw: use HZ_PER_KHZ macro in units.h
  cpufreq: mediatek: fix error return code in mtk_cpu_dvfs_info_init()
  OPP: Remove dev{m}_pm_opp_of_add_table_noclk()
  PM / devfreq: tegra30: Register config_clks helper
  OPP: Allow config_clks helper for single clk case
  OPP: Provide a simple implementation to configure multiple clocks
  OPP: Assert clk_count == 1 for single clk helpers
  ...

Pull 9p updates from Dominique Martinet:

 - a couple of fixes

 - add a tracepoint for fid refcounting

 - some cleanup/followup on fid lookup

 - some cleanup around req refcounting

* tag '9p-for-5.20' of https://github.com/martinetd/linux:
  net/9p: Initialize the iounit field during fid creation
  net: 9p: fix refcount leak in p9_read_work() error handling
  9p: roll p9_tag_remove into p9_req_put
  9p: Add client parameter to p9_req_put()
  9p: Drop kref usage
  9p: Fix some kernel-doc comments
  9p fid refcount: cleanup p9_fid_put calls
  9p fid refcount: add a 9p_fid_ref tracepoint
  9p fid refcount: add p9_fid_get/put wrappers
  9p: Fix minor typo in code comment
  9p: Remove unnecessary variable for old fids while walking from d_parent
  9p: Make the path walk logic more clear about when cloning is required
  9p: Track the root fid with its own variable during lookups