I got the following error when I tried to build perf on a read-only
filesystem with O=dir option.

  $ cd /some/where/ro/linux/tools/perf
  $ make O=$HOME/build/perf
  ...
    CC       /home/namhyung/build/perf/lib.o
  /bin/sh: bpf_helper_defs.h: Read-only file system
  make[3]: *** [Makefile:184: bpf_helper_defs.h] Error 1
  make[2]: *** [Makefile.perf:778: /home/namhyung/build/perf/libbpf.a] Error 2
  make[2]: *** Waiting for unfinished jobs....
    LD       /home/namhyung/build/perf/libperf-in.o
    AR       /home/namhyung/build/perf/libperf.a
    PERF_VERSION = 5.4.0
  make[1]: *** [Makefile.perf:225: sub-make] Error 2
  make: *** [Makefile:70: all] Error 2

It was becaused bpf_helper_defs.h was generated in current directory.
Move it to OUTPUT directory.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191223061326.843366-1-namhyung@kernel.org

Anatoly has been fuzzing with kBdysch harness and reported a hang in one
of the outcomes. Upon closer analysis, it turns out that precise scalar
value tracking is missing a few precision markings for unknown scalars:

  0: R1=ctx(id=0,off=0,imm=0) R10=fp0
  0: (b7) r0 = 0
  1: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
  1: (35) if r0 >= 0xf72e goto pc+0
  --> only follow fallthrough
  2: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
  2: (35) if r0 >= 0x80fe0000 goto pc+0
  --> only follow fallthrough
  3: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
  3: (14) w0 -= -536870912
  4: R0_w=invP536870912 R1=ctx(id=0,off=0,imm=0) R10=fp0
  4: (0f) r1 += r0
  5: R0_w=invP536870912 R1_w=inv(id=0) R10=fp0
  5: (55) if r1 != 0x104c1500 goto pc+0
  --> push other branch for later analysis
  R0_w=invP536870912 R1_w=inv273421568 R10=fp0
  6: R0_w=invP536870912 R1_w=inv273421568 R10=fp0
  6: (b7) r0 = 0
  7: R0=invP0 R1=inv273421568 R10=fp0
  7: (76) if w1 s>= 0xffffff00 goto pc+3
  --> only follow goto
  11: R0=invP0 R1=inv273421568 R10=fp0
  11: (95) exit
  6: R0_w=invP536870912 R1_w=inv(id=0) R10=fp0
  6: (b7) r0 = 0
  propagating r0
  7: safe
  processed 11 insns [...]

In the analysis of the second path coming after the successful exit above,
the path is being pruned at line 7. Pruning analysis found that both r0 are
precise P0 and both R1 are non-precise scalars and given prior path with
R1 as non-precise scalar succeeded, this one is therefore safe as well.

However, problem is that given condition at insn 7 in the first run, we only
followed goto and didn't push the other branch for later analysis, we've
never walked the few insns in there and therefore dead-code sanitation
rewrites it as goto pc-1, causing the hang depending on the skb address
hitting these conditions. The issue is that R1 should have been marked as
precise as well such that pruning enforces range check and conluded that new
R1 is not in range of old R1. In insn 4, we mark R1 (skb) as unknown scalar
via __mark_reg_unbounded() but not mark_reg_unbounded() and therefore
regs->precise remains as false.

Back in b5dc0163 ("bpf: precise scalar_value tracking"), this was not
the case since marking out of __mark_reg_unbounded() had this covered as well.
Once in both are set as precise in 4 as they should have been, we conclude
that given R1 was in prior fall-through path 0x104c1500 and now is completely
unknown, the check at insn 7 concludes that we need to continue walking.
Analysis after the fix:

  0: R1=ctx(id=0,off=0,imm=0) R10=fp0
  0: (b7) r0 = 0
  1: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
  1: (35) if r0 >= 0xf72e goto pc+0
  2: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
  2: (35) if r0 >= 0x80fe0000 goto pc+0
  3: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
  3: (14) w0 -= -536870912
  4: R0_w=invP536870912 R1=ctx(id=0,off=0,imm=0) R10=fp0
  4: (0f) r1 += r0
  5: R0_w=invP536870912 R1_w=invP(id=0) R10=fp0
  5: (55) if r1 != 0x104c1500 goto pc+0
  R0_w=invP536870912 R1_w=invP273421568 R10=fp0
  6: R0_w=invP536870912 R1_w=invP273421568 R10=fp0
  6: (b7) r0 = 0
  7: R0=invP0 R1=invP273421568 R10=fp0
  7: (76) if w1 s>= 0xffffff00 goto pc+3
  11: R0=invP0 R1=invP273421568 R10=fp0
  11: (95) exit
  6: R0_w=invP536870912 R1_w=invP(id=0) R10=fp0
  6: (b7) r0 = 0
  7: R0_w=invP0 R1_w=invP(id=0) R10=fp0
  7: (76) if w1 s>= 0xffffff00 goto pc+3
  R0_w=invP0 R1_w=invP(id=0) R10=fp0
  8: R0_w=invP0 R1_w=invP(id=0) R10=fp0
  8: (a5) if r0 < 0x2007002a goto pc+0
  9: R0_w=invP0 R1_w=invP(id=0) R10=fp0
  9: (57) r0 &= -16316416
  10: R0_w=invP0 R1_w=invP(id=0) R10=fp0
  10: (a6) if w0 < 0x1201 goto pc+0
  11: R0_w=invP0 R1_w=invP(id=0) R10=fp0
  11: (95) exit
  11: R0=invP0 R1=invP(id=0) R10=fp0
  11: (95) exit
  processed 16 insns [...]

Fixes: 6754172c ("bpf: fix precision tracking in presence of bpf2bpf calls")
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191222223740.25297-1-daniel@iogearbox.net

Pull xfs fixes from Darrick Wong:
 "Fix a few bugs that could lead to corrupt files, fsck complaints, and
  filesystem crashes:

   - Minor documentation fixes

   - Fix a file corruption due to read racing with an insert range
     operation.

   - Fix log reservation overflows when allocating large rt extents

   - Fix a buffer log item flags check

   - Don't allow administrators to mount with sunit= options that will
     cause later xfs_repair complaints about the root directory being
     suspicious because the fs geometry appeared inconsistent

   - Fix a non-static helper that should have been static"

* tag 'xfs-5.5-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: Make the symbol 'xfs_rtalloc_log_count' static
  xfs: don't commit sunit/swidth updates to disk if that would cause repair failures
  xfs: split the sunit parameter update into two parts
  xfs: refactor agfl length computation function
  libxfs: resync with the userspace libxfs
  xfs: use bitops interface for buf log item AIL flag check
  xfs: fix log reservation overflows when allocating large rt extents
  xfs: stabilize insert range start boundary to avoid COW writeback race
  xfs: fix Sphinx documentation warning

Pull ext4 bug fixes from Ted Ts'o:
 "Ext4 bug fixes, including a regression fix"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: clarify impact of 'commit' mount option
  ext4: fix unused-but-set-variable warning in ext4_add_entry()
  jbd2: fix kernel-doc notation warning
  ext4: use RCU API in debug_print_tree
  ext4: validate the debug_want_extra_isize mount option at parse time
  ext4: reserve revoke credits in __ext4_new_inode
  ext4: unlock on error in ext4_expand_extra_isize()
  ext4: optimize __ext4_check_dir_entry()
  ext4: check for directory entries too close to block end
  ext4: fix ext4_empty_dir() for directories with holes

Pull block fixes from Jens Axboe:
 "Let's try this one again, this time without the compat_ioctl changes.
  We've got those fixed up, but that can go out next week.

  This contains:

   - block queue flush lockdep annotation (Bart)

   - Type fix for bsg_queue_rq() (Bart)

   - Three dasd fixes (Stefan, Jan)

   - nbd deadlock fix (Mike)

   - Error handling bio user map fix (Yang)

   - iocost fix (Tejun)

   - sbitmap waitqueue addition fix that affects the kyber IO scheduler
     (David)"

* tag 'block-5.5-20191221' of git://git.kernel.dk/linux-block:
  sbitmap: only queue kyber's wait callback if not already active
  block: fix memleak when __blk_rq_map_user_iov() is failed
  s390/dasd: fix typo in copyright statement
  s390/dasd: fix memleak in path handling error case
  s390/dasd/cio: Interpret ccw_device_get_mdc return value correctly
  block: Fix a lockdep complaint triggered by request queue flushing
  block: Fix the type of 'sts' in bsg_queue_rq()
  block: end bio with BLK_STS_AGAIN in case of non-mq devs and REQ_NOWAIT
  nbd: fix shutdown and recv work deadlock v2
  iocost: over-budget forced IOs should schedule async delay

Pull KVM fixes from Paolo Bonzini:
 "PPC:
   - Fix a bug where we try to do an ultracall on a system without an
     ultravisor

  KVM:
   - Fix uninitialised sysreg accessor
   - Fix handling of demand-paged device mappings
   - Stop spamming the console on IMPDEF sysregs
   - Relax mappings of writable memslots
   - Assorted cleanups

  MIPS:
   - Now orphan, James Hogan is stepping down

  x86:
   - MAINTAINERS change, so long Radim and thanks for all the fish
   - supported CPUID fixes for AMD machines without SPEC_CTRL"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  MAINTAINERS: remove Radim from KVM maintainers
  MAINTAINERS: Orphan KVM for MIPS
  kvm: x86: Host feature SSBD doesn't imply guest feature AMD_SSBD
  kvm: x86: Host feature SSBD doesn't imply guest feature SPEC_CTRL_SSBD
  KVM: PPC: Book3S HV: Don't do ultravisor calls on systems without ultravisor
  KVM: arm/arm64: Properly handle faulting of device mappings
  KVM: arm64: Ensure 'params' is initialised when looking up sys register
  KVM: arm/arm64: Remove excessive permission check in kvm_arch_prepare_memory_region
  KVM: arm64: Don't log IMP DEF sysreg traps
  KVM: arm64: Sanely ratelimit sysreg messages
  KVM: arm/arm64: vgic: Use wrapper function to lock/unlock all vcpus in kvm_vgic_create()
  KVM: arm/arm64: vgic: Fix potential double free dist->spis in __kvm_vgic_destroy()
  KVM: arm/arm64: Get rid of unused arg in cpu_init_hyp_mode()

Pull RISC-V fixes from Paul Walmsley:
 "Several fixes, and one cleanup, for RISC-V.

  Fixes:

   - Fix an error in a Kconfig file that resulted in an undefined
     Kconfig option "CONFIG_CONFIG_MMU"

   - Fix undefined Kconfig option "CONFIG_CONFIG_MMU"

   - Fix scratch register clearing in M-mode (affects nommu users)

   - Fix a mismerge on my part that broke the build for
     CONFIG_SPARSEMEM_VMEMMAP users

  Cleanup:

   - Move SiFive L2 cache-related code to drivers/soc, per request"

* tag 'riscv/for-v5.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: move sifive_l2_cache.c to drivers/soc
  riscv: define vmemmap before pfn_to_page calls
  riscv: fix scratch register clearing in M-mode.
  riscv: Fix use of undefined config option CONFIG_CONFIG_MMU

Pull networking fixes from David Miller:

 1) Several nf_flow_table_offload fixes from Pablo Neira Ayuso,
    including adding a missing ipv6 match description.

 2) Several heap overflow fixes in mwifiex from qize wang and Ganapathi
    Bhat.

 3) Fix uninit value in bond_neigh_init(), from Eric Dumazet.

 4) Fix non-ACPI probing of nxp-nci, from Stephan Gerhold.

 5) Fix use after free in tipc_disc_rcv(), from Tuong Lien.

 6) Enforce limit of 33 tail calls in mips and riscv JIT, from Paul
    Chaignon.

 7) Multicast MAC limit test is off by one in qede, from Manish Chopra.

 8) Fix established socket lookup race when socket goes from
    TCP_ESTABLISHED to TCP_LISTEN, because there lacks an intervening
    RCU grace period. From Eric Dumazet.

 9) Don't send empty SKBs from tcp_write_xmit(), also from Eric Dumazet.

10) Fix active backup transition after link failure in bonding, from
    Mahesh Bandewar.

11) Avoid zero sized hash table in gtp driver, from Taehee Yoo.

12) Fix wrong interface passed to ->mac_link_up(), from Russell King.

13) Fix DSA egress flooding settings in b53, from Florian Fainelli.

14) Memory leak in gmac_setup_txqs(), from Navid Emamdoost.

15) Fix double free in dpaa2-ptp code, from Ioana Ciornei.

16) Reject invalid MTU values in stmmac, from Jose Abreu.

17) Fix refcount leak in error path of u32 classifier, from Davide
    Caratti.

18) Fix regression causing iwlwifi firmware crashes on boot, from Anders
    Kaseorg.

19) Fix inverted return value logic in llc2 code, from Chan Shu Tak.

20) Disable hardware GRO when XDP is attached to qede, frm Manish
    Chopra.

21) Since we encode state in the low pointer bits, dst metrics must be
    at least 4 byte aligned, which is not necessarily true on m68k. Add
    annotations to fix this, from Geert Uytterhoeven.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (160 commits)
  sfc: Include XDP packet headroom in buffer step size.
  sfc: fix channel allocation with brute force
  net: dst: Force 4-byte alignment of dst_metrics
  selftests: pmtu: fix init mtu value in description
  hv_netvsc: Fix unwanted rx_table reset
  net: phy: ensure that phy IDs are correctly typed
  mod_devicetable: fix PHY module format
  qede: Disable hardware gro when xdp prog is installed
  net: ena: fix issues in setting interrupt moderation params in ethtool
  net: ena: fix default tx interrupt moderation interval
  net/smc: unregister ib devices in reboot_event
  net: stmmac: platform: Fix MDIO init for platforms without PHY
  llc2: Fix return statement of llc_stat_ev_rx_null_dsap_xid_c (and _test_c)
  net: hisilicon: Fix a BUG trigered by wrong bytes_compl
  net: dsa: ksz: use common define for tag len
  s390/qeth: don't return -ENOTSUPP to userspace
  s390/qeth: fix promiscuous mode after reset
  s390/qeth: handle error due to unsupported transport mode
  cxgb4: fix refcount init for TC-MQPRIO offload
  tc-testing: initial tdc selftests for cls_u32
  ...

LTP pipeio_1 test is hanging with v5.5-rc2-385-gb8e382a1,
with read side observing empty pipe and sleeping and write
side running out of space and then sleeping as well. In this
scenario there are 5 writers and 1 reader.

Problem is that after pipe_write() reacquires pipe lock, it
re-checks for empty pipe with potentially stale 'head' and
doesn't wake up read side anymore. pipe->tail can advance
beyond 'head', because there are multiple writers.

Use pipe->head for empty pipe check after reacquiring lock
to observe current state.

Testing: With patch, LTP pipeio_1 ran successfully in loop for 1 hour.
         Without patch it hanged within a minute.

Fixes: 1b6b26ae ("pipe: fix and clarify pipe write wakeup logic")
Reported-by: Rachel Sibley <rasibley@redhat.com>
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'kvm-ppc-fixes-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into kvm-master

PPC KVM fix for 5.5

- Fix a bug where we try to do an ultracall on a system without an
  ultravisor.

Radim's kernel.org email is bouncing, which I take as a signal that
he is not really able to deal with KVM at this time.  Make MAINTAINERS
match the effective value of KVM's bus factor.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

I haven't been active for 18 months, and don't have the hardware set up
to test KVM for MIPS, so mark it as orphaned and remove myself as
maintainer. Hopefully somebody from MIPS can pick this up.
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: kvm@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The description of 'commit' mount option dates back to ext3 times.
Update the description to match current meaning for ext4.
Reported-by: Paul Richards <paul.richards@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191218111210.14161-1-jack@suse.czSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Warning is found when compile with "-Wunused-but-set-variable":

fs/ext4/namei.c: In function ‘ext4_add_entry’:
fs/ext4/namei.c:2167:23: warning: variable ‘sbi’ set but not used
[-Wunused-but-set-variable]
  struct ext4_sb_info *sbi;
                       ^~~
Fix this by moving the variable @sbi under CONFIG_UNICODE.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/cb5eb904-224a-9701-c38f-cb23514b1fff@huawei.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Pull tracing fixes from Steven Rostedt:

 - Fix memory leak on error path of process_system_preds()

 - Lock inversion fix with updating tgid recording option

 - Fix histogram compare function on big endian machines

 - Fix histogram trigger function on big endian machines

 - Make trace_printk() irq sync on init for kprobe selftest correctness

* tag 'trace-v5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix endianness bug in histogram trigger
  samples/trace_printk: Wait for IRQ work to finish
  tracing: Fix lock inversion in trace_event_enable_tgid_record()
  tracing: Have the histogram compare functions convert to u64 first
  tracing: Avoid memory leak in process_system_preds()

Pull libnvdimm fix from Dan Williams:
 "A minor regression fix.

  The libnvdimm unit tests were expecting to mock calls to
  ioremap_nocache() which disappeared in v5.5-rc1. This fix has appeared
  in -next and collided with some cleanups that Christoph has planned
  for v5.6, but he will fix up his branch once this goes in.

  Summary:

   - Restore the operation of the libnvdimm unit tests after the removal
     of ioremap_nocache()"

* tag 'libnvdimm-fix-5.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  tools/testing/nvdimm: Fix mock support for ioremap

At least on PA-RISC and s390 synthetic histogram triggers are failing
selftests because trace_event_raw_event_synth() always writes a 64 bit
values, but the reader expects a field->size sized value. On little endian
machines this doesn't hurt, but on big endian this makes the reader always
read zero values.

Link: http://lore.kernel.org/linux-trace-devel/20191218074427.96184-4-svens@linux.ibm.com

Cc: stable@vger.kernel.org
Fixes: 4b147936 ("tracing: Add support for 'synthetic' events")
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

trace_printk schedules work via irq_work_queue(), but doesn't
wait until it was processed. The kprobe_module.tc testcase does:

:;: "Load module again, which means the event1 should be recorded";:
modprobe trace-printk
grep "event1:" trace

so the grep which checks the trace file might run before the irq work
was processed. Fix this by adding a irq_work_sync().

Link: http://lore.kernel.org/linux-trace-devel/20191218074427.96184-3-svens@linux.ibm.com

Cc: stable@vger.kernel.org
Fixes: af2a0750 ("selftests/ftrace: Improve kprobe on module testcase to load/unload module")
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

       Task T2                             Task T3
trace_options_core_write()            subsystem_open()

 mutex_lock(trace_types_lock)           mutex_lock(event_mutex)

 set_tracer_flag()

   trace_event_enable_tgid_record()       mutex_lock(trace_types_lock)

    mutex_lock(event_mutex)

This gives a circular dependency deadlock between trace_types_lock and
event_mutex. To fix this invert the usage of trace_types_lock and
event_mutex in trace_options_core_write(). This keeps the sequence of
lock usage consistent.

Link: http://lkml.kernel.org/r/0101016eef175e38-8ca71caf-a4eb-480d-a1e6-6f0bbc015495-000000@us-west-2.amazonses.com

Cc: stable@vger.kernel.org
Fixes: d914ba37 ("tracing: Add support for recording tgid of tasks")
Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Pull s390 fixes from Vasily Gorbik:

 - Fix unwinding from irq context of interrupted user process.

 - Add purgatory build missing symbols check. That helped to uncover and
   fix missing symbols when built with kasan support enabled.

 - Couple of ftrace fixes. Avoid broken stack trace and fix recursion
   loop in function_graph tracer.

* tag 's390-5.5-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/ftrace: save traced function caller
  s390/unwind: stop gracefully at user mode pt_regs in irq stack
  s390/purgatory: do not build purgatory with kcov, kasan and friends
  s390/purgatory: Make sure we fail the build if purgatory has missing symbols
  s390/ftrace: fix endless recursion in function_graph tracer

Pull scheduler fixes from Ingo Molnar:
 "Misc fixes: a (rare) PSI crash fix, a CPU affinity related balancing
  fix, and a toning down of active migration attempts"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/cfs: fix spurious active migration
  sched/fair: Fix find_idlest_group() to handle CPU affinity
  psi: Fix a division error in psi poll()
  sched/psi: Fix sampling error and rare div0 crashes with cgroups and high uptime

Pull perf fixes from Ingo Molnar:
 "Misc fixes: a BTS fix, a PT NMI handling fix, a PMU sysfs fix and an
  SRCU annotation"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Add SRCU annotation for pmus list walk
  perf/x86/intel: Fix PT PMI handling
  perf/x86/intel/bts: Fix the use of page_private()
  perf/x86: Fix potential out-of-bounds access

Merge tag 'kbuild-fixes-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - fix warning in out-of-tree 'make clean'

 - add READELF variable to the top Makefile

 - fix broken builds when LINUX_COMPILE_BY contains a backslash

 - fix build warning in kallsyms

 - fix NULL pointer access in expr_eq() in Kconfig

 - fix missing dependency on rsync in deb-pkg build

 - remove ---help--- from documentation

 - fix misleading documentation about directory descending

* tag 'kbuild-fixes-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: clarify the difference between obj-y and obj-m w.r.t. descending
  kconfig: remove ---help--- from documentation
  scripts: package: mkdebian: add missing rsync dependency
  kconfig: don't crash on NULL expressions in expr_eq()
  scripts/kallsyms: fix offset overflow of kallsyms_relative_base
  mkcompile_h: use printf for LINUX_COMPILE_BY
  mkcompile_h: git rid of UTS_TRUNCATE from LINUX_COMPILE_{BY,HOST}
  x86/boot: kbuild: allow readelf executable to be specified
  kbuild: fix 'No such file or directory' warning when cleaning

Kbuild descends into a directory by either 'y' or 'm', but there is an
important difference.

Kbuild combines the built-in objects into built-in.a in each directory.
The built-in.a in the directory visited by obj-y is merged into the
built-in.a in the parent directory. This merge happens recursively
when Kbuild is ascending back towards the top directory, then built-in
objects are linked into vmlinux eventually. This works properly only
when the Makefile specifying obj-y is reachable by the chain of obj-y.

On the other hand, Kbuild does not take built-in.a from the directory
visited by obj-m. This it, all the objects in that directory are
supposed to be modular. If Kbuild descends into a directory by obj-m,
but the Makefile in the sub-directory specifies obj-y, those objects
are just left orphan.

The current statement "Kbuild only uses this information to decide that
it needs to visit the directory" is misleading. Clarify the difference.
Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Johan Hovold <johan@kernel.org>

Pul parisc fixes from Helge Deller:
 "Two build error fixes, one for the soft_offline_page() parameter
  change and one for a specific KEXEC/KEXEC_FILE configuration, as well
  as a compiler and a linker warning fix"

* 'parisc-5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Fix compiler warnings in debug_core.c
  parisc: soft_offline_page() now takes the pfn
  parisc: add missing __init annotation
  parisc: fix compilation when KEXEC=n and KEXEC_FILE=y

Pull xen fixes from Juergen Gross:
 "This contains two cleanup patches and a small series for supporting
  reloading the Xen block backend driver"

* tag 'for-linus-5.5b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/grant-table: remove multiple BUG_ON on gnttab_interface
  xen-blkback: support dynamic unbind/bind
  xen/interface: re-define FRONT/BACK_RING_ATTACH()
  xenbus: limit when state is forced to closed
  xenbus: move xenbus_dev_shutdown() into frontend code...
  xen/blkfront: Adjust indentation in xlvbd_alloc_gendisk

Pull powerpc fixes from Michael Ellerman:
 "Two weeks worth of accumulated fixes:

   - A fix for a performance regression seen on PowerVM LPARs using
     dedicated CPUs, caused by our vcpu_is_preempted() returning true
     even for idle CPUs.

   - One of the ultravisor support patches broke KVM on big endian hosts
     in v5.4.

   - Our KUAP (Kernel User Access Prevention) code missed allowing
     access in __clear_user(), which could lead to an oops or erroneous
     SEGV when triggered via PTRACE_GETREGSET.

   - Two fixes for the ocxl driver, an open/remove race, and a memory
     leak in an error path.

   - A handful of other small fixes.

  Thanks to: Andrew Donnellan, Christian Zigotzky, Christophe Leroy,
  Christoph Hellwig, Daniel Axtens, David Hildenbrand, Frederic Barrat,
  Gautham R. Shenoy, Greg Kurz, Ihor Pasichnyk, Juri Lelli, Marcus
  Comstedt, Mike Rapoport, Parth Shah, Srikar Dronamraju, Vaidyanathan
  Srinivasan"

* tag 'powerpc-5.5-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  KVM: PPC: Book3S HV: Fix regression on big endian hosts
  powerpc: Fix __clear_user() with KUAP enabled
  powerpc/pseries/cmm: fix managed page counts when migrating pages between zones
  powerpc/8xx: fix bogus __init on mmu_mapin_ram_chunk()
  ocxl: Fix potential memory leak on context creation
  powerpc/irq: fix stack overflow verification
  powerpc: Ensure that swiotlb buffer is allocated from low memory
  powerpc/shared: Use static key to detect shared processor
  powerpc/vcpu: Assume dedicated processors as non-preempt
  ocxl: Fix concurrent AFU open and device removal

Pull x86 RAS fixes from Borislav Petkov:
 "Three urgent RAS fixes for the AMD side of things:

   - initialize struct mce.bank so that calculated error severity on AMD
     SMCA machines is correct

   - do not send IPIs early during bank initialization, when interrupts
     are disabled

   - a fix for when only a subset of MCA banks are enabled, which led to
     boot hangs on some new AMD CPUs"

* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Fix possibly incorrect severity calculation on AMD
  x86/MCE/AMD: Allow Reserved types to be overwritten in smca_banks[]
  x86/MCE/AMD: Do not use rdmsr_safe_on_cpu() in smca_configure()

Pull clk fixes from Stephen Boyd:
 "One core framework fix to walk the orphan list and match up clks to
  parents when clk providers register the DT provider after registering
  all their clks (as they should).

  Then a handful of driver fixes for the qcom, imx, and at91 drivers.

  The driver fixes are relatively small fixes for incorrect register
  settings or missing locks causing race conditions"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: qcom: Avoid SMMU/cx gdsc corner cases
  clk: qcom: gcc-sc7180: Fix setting flag for votable GDSCs
  clk: Move clk_core_reparent_orphans() under CONFIG_OF
  clk: at91: fix possible deadlock
  clk: walk orphan list on clock provider registration
  clk: imx: pll14xx: fix clk_pll14xx_wait_lock
  clk: imx: clk-imx7ulp: Add missing sentinel of ulp_div_table
  clk: imx: clk-composite-8m: add lock to gate/mux

Edward Cree says:

====================
sfc: fix bugs introduced by XDP patches

Two fixes for bugs introduced by the XDP support in the sfc driver.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Correct a mismatch between rx_page_buf_step and the actual step size
used when filling buffer pages.

This patch fixes the page overrun that occured when the MTU was set to
anything bigger than 1692.

Fixes: 3990a8ff ("sfc: allocate channels for XDP tx queues")
Signed-off-by: Charles McLachlan <cmclachlan@solarflare.com>
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It was possible for channel allocation logic to get confused between what
 it had and what it wanted, and end up trying to use the same channel for
 both PTP and regular TX.  This led to a kernel panic:
    BUG: unable to handle page fault for address: 0000000000047635
    #PF: supervisor write access in kernel mode
    #PF: error_code(0x0002) - not-present page
    PGD 0 P4D 0
    Oops: 0002 [#1] SMP PTI
    CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W         5.4.0-rc3-ehc14+ #900
    Hardware name: Dell Inc. PowerEdge R710/0M233H, BIOS 6.4.0 07/23/2013
    RIP: 0010:native_queued_spin_lock_slowpath+0x188/0x1e0
    Code: f3 90 48 8b 32 48 85 f6 74 f6 eb e8 c1 ee 12 83 e0 03 83 ee 01 48 c1 e0 05 48 63 f6 48 05 c0 98 02 00 48 03 04 f5 a0 c6 ed 81 <48> 89 10 8b 42 08 85 c0 75 09 f3 90 8b 42 08 85 c0 74 f7 48 8b 32
    RSP: 0018:ffffc90000003d28 EFLAGS: 00010006
    RAX: 0000000000047635 RBX: 0000000000000246 RCX: 0000000000040000
    RDX: ffff888627a298c0 RSI: 0000000000003ffe RDI: ffff88861f6b8dd4
    RBP: ffff8886225c6e00 R08: 0000000000040000 R09: 0000000000000000
    R10: 0000000616f080c6 R11: 00000000000000c0 R12: ffff88861f6b8dd4
    R13: ffffc90000003dc8 R14: ffff88861942bf00 R15: ffff8886150f2000
    FS:  0000000000000000(0000) GS:ffff888627a00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000000047635 CR3: 000000000200a000 CR4: 00000000000006f0
    Call Trace:
     <IRQ>
     _raw_spin_lock_irqsave+0x22/0x30
     skb_queue_tail+0x1b/0x50
     sock_queue_err_skb+0x9d/0xf0
     __skb_complete_tx_timestamp+0x9d/0xc0
     efx_dequeue_buffer+0x126/0x180 [sfc]
     efx_xmit_done+0x73/0x1c0 [sfc]
     efx_ef10_ev_process+0x56a/0xfe0 [sfc]
     ? tick_sched_do_timer+0x60/0x60
     ? timerqueue_add+0x5d/0x70
     ? enqueue_hrtimer+0x39/0x90
     efx_poll+0x111/0x380 [sfc]
     ? rcu_accelerate_cbs+0x50/0x160
     net_rx_action+0x14a/0x400
     __do_softirq+0xdd/0x2d0
     irq_exit+0xa0/0xb0
     do_IRQ+0x53/0xe0
     common_interrupt+0xf/0xf
     </IRQ>

In the long run we intend to rewrite the channel allocation code, but for
 'net' fix this by allocating extra_channels, and giving them TX queues,
 even if we do not in fact need them (e.g. on NICs without MAC TX
 timestamping), and thereby using simpler logic to assign the channels
 once they're allocated.

Fixes: 3990a8ff ("sfc: allocate channels for XDP tx queues")
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When storing a pointer to a dst_metrics structure in dst_entry._metrics,
two flags are added in the least significant bits of the pointer value.
Hence this assumes all pointers to dst_metrics structures have at least
4-byte alignment.

However, on m68k, the minimum alignment of 32-bit values is 2 bytes, not
4 bytes.  Hence in some kernel builds, dst_default_metrics may be only
2-byte aligned, leading to obscure boot warnings like:

    WARNING: CPU: 0 PID: 7 at lib/refcount.c:28 refcount_warn_saturate+0x44/0x9a
    refcount_t: underflow; use-after-free.
    Modules linked in:
    CPU: 0 PID: 7 Comm: ksoftirqd/0 Tainted: G        W         5.5.0-rc2-atari-01448-g114a1a1038af891d-dirty #261
    Stack from 10835e6c:
	    10835e6c 0038134f 00023fa6 00394b0f 0000001c 00000009 00321560 00023fea
	    00394b0f 0000001c 001a70f8 00000009 00000000 10835eb4 00000001 00000000
	    04208040 0000000a 00394b4a 10835ed4 00043aa8 001a70f8 00394b0f 0000001c
	    00000009 00394b4a 0026aba8 003215a4 00000003 00000000 0026d5a8 00000001
	    003215a4 003a4361 003238d6 000001f0 00000000 003215a4 10aa3b00 00025e84
	    003ddb00 10834000 002416a8 10aa3b00 00000000 00000080 000aa038 0004854a
    Call Trace: [<00023fa6>] __warn+0xb2/0xb4
     [<00023fea>] warn_slowpath_fmt+0x42/0x64
     [<001a70f8>] refcount_warn_saturate+0x44/0x9a
     [<00043aa8>] printk+0x0/0x18
     [<001a70f8>] refcount_warn_saturate+0x44/0x9a
     [<0026aba8>] refcount_sub_and_test.constprop.73+0x38/0x3e
     [<0026d5a8>] ipv4_dst_destroy+0x5e/0x7e
     [<00025e84>] __local_bh_enable_ip+0x0/0x8e
     [<002416a8>] dst_destroy+0x40/0xae

Fix this by forcing 4-byte alignment of all dst_metrics structures.

Fixes: e5fd387a ("ipv6: do not overwrite inetpeer metrics prematurely")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

There is no a_r3, a_r4 in the testing topology.
It should be b_r1, b_r2. Also b_r1 mtu is 1400 and b_r2 mtu is 1500.

Fixes: e44e428f ("selftests: pmtu: add basic IPv4 and IPv6 PMTU tests")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In existing code, the receive indirection table, rx_table, is in
struct rndis_device, which will be reset when changing MTU, ringparam,
etc. User configured receive indirection table values will be lost.

To fix this, move rx_table to struct net_device_context, and check
netif_is_rxfh_configured(), so rx_table will be set to default only
if no user configured value.

Fixes: ff4a4419 ("netvsc: allow get/set of RSS indirection table")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

PHY IDs are 32-bit unsigned quantities. Ensure that they are always
treated as such, and not passed around as "int"s.

Fixes: 13d0ab67 ("net: phy: check return code when requesting PHY driver module")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

When a PHY is probed, if the top bit is set, we end up requesting a
module with the string "mdio:-10101110000000100101000101010001" -
the top bit is printed to a signed -1 value. This leads to the module
not being loaded.

Fix the module format string and the macro generating the values for
it to ensure that we only print unsigned types and the top bit is
always 0/1. We correctly end up with
"mdio:10101110000000100101000101010001".

Fixes: 8626d3b4 ("phylib: Support phy module autoloading")
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

commit 18c602de ("qede: Use NETIF_F_GRO_HW.") introduced
a regression in driver that when xdp program is installed on
qede device, device's aggregation feature (hardware GRO) is not
getting disabled, which is unexpected with xdp.

Fixes: 18c602de ("qede: Use NETIF_F_GRO_HW.")
Signed-off-by: Manish Chopra <manishc@marvell.com>
Signed-off-by: Ariel Elior <aelior@marvell.com>
Reviewed-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Arthur Kiyanovski says:

====================
ena: fixes of interrupt moderation bugs

Differences from V1:
1. Updated default tx interrupt moderation to 64us
2. Added "Fixes:" tags.
3. Removed cosmetic changes that are not relevant for these bug fixes

This patchset includes a couple of fixes of bugs in the implemenation of
interrupt moderation.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Issue 1:
--------
Reproduction steps:
1. sudo ethtool -C eth0 rx-usecs 128
2. sudo ethtool -C eth0 adaptive-rx on
3. sudo ethtool -C eth0 adaptive-rx off
4. ethtool -c eth0

expected output: rx-usecs 128
actual output: rx-usecs 0

Reason for issue:
In stage 3, ethtool userspace calls first the ena_get_coalesce() handler
to get the current value of all properties, and then the ena_set_coalesce()
handler. When ena_get_coalesce() is called the adaptive interrupt
moderation is still on. There is an if in the code that returns the
rx_coalesce_usecs only if the adaptive interrupt moderation is off.
And since it is still on, rx_coalesce_usecs is not set, meaning it
stays 0.

Solution to issue:
Remove this if static interrupt moderation intervals have nothing to do
with dynamic ones.

Issue 2:
--------
Reproduction steps:
1. sudo ethtool -C eth0 adaptive-rx on
2. sudo ethtool -C eth0 rx-usecs 128
3. ethtool -c eth0

expected output: rx-usecs 128
actual output: rx-usecs 0

Reason for issue:
In stage 2, when ena_set_coalesce() is called, the handler tests if
rx adaptive interrupt moderation is on, and if it is, it returns before
getting to the part in the function that sets the rx non-adaptive
interrupt moderation interval.

Solution to issue:
Remove the return from the function when rx adaptive interrupt moderation
is on.

Also cleaned up the fixed code in ena_set_coalesce by grouping together
adaptive interrupt moderation toggling, and using && instead of nested
ifs.

Fixes: b3db86dc ("net: ena: reimplement set/get_coalesce()")
Fixes: 0eda8479 ("net: ena: fix retrieval of nonadaptive interrupt moderation intervals")
Fixes: 1738cd3e ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)")
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>