If the no_hash_pointers command line parameter is set, then
printk("%p") will print pointers as unhashed, which is useful for
debugging purposes.  This change applies to any function that uses
vsprintf, such as print_hex_dump() and seq_buf_printf().

A large warning message is displayed if this option is enabled.
Unhashed pointers expose kernel addresses, which can be a security
risk.

Also update test_printf to skip the hashed pointer tests if the
command-line option is set.
Signed-off-by: Timur Tabi <timur@kernel.org>
Acked-by: Petr Mladek <pmladek@suse.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210214161348.369023-4-timur@kernel.org

Update the kselftest framework to allow client drivers to
specify that some tests were skipped.
Signed-off-by: Timur Tabi <timur@kernel.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210214161348.369023-3-timur@kernel.org

Instead of defining the total/failed test counters manually,
test drivers that are clients of kselftest should use the
macro created for this purpose.
Signed-off-by: Timur Tabi <timur@kernel.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210214161348.369023-2-timur@kernel.org

If message sizes average larger than expected (more than 32
characters), the data_ring will wrap before the desc_ring. Once the
data_ring wraps, it will start invalidating descriptors. These
invalid descriptors hang around until they are eventually recycled
when the desc_ring wraps. Readers do not care about invalid
descriptors, but they still need to iterate past them. If the
average message size is much larger than 32 characters, then there
will be many invalid descriptors preceding the valid descriptors.

The function prb_first_valid_seq() always begins at the oldest
descriptor and searches for the first valid descriptor. This can
be rather expensive for the above scenario. And, in fact, because
of its heavy usage in /dev/kmsg, there have been reports of long
delays and even RCU stalls.

For code that does not need to search from the oldest record,
replace prb_first_valid_seq() usage with prb_read_valid_*()
functions, which provide a start sequence number to search from.

Fixes: 896fbe20 ("printk: use the lockless ringbuffer")
Reported-by: kernel test robot <oliver.sang@intel.com>
Reported-by: J. Avila <elavila@google.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210211173152.1629-1-john.ogness@linutronix.de

printk_safe_flush_on_panic() caused the following deadlock on our
server:

CPU0:                                         CPU1:
panic                                         rcu_dump_cpu_stacks
  kdump_nmi_shootdown_cpus                      nmi_trigger_cpumask_backtrace
    register_nmi_handler(crash_nmi_callback)      printk_safe_flush
                                                    __printk_safe_flush
                                                      raw_spin_lock_irqsave(&read_lock)
    // send NMI to other processors
    apic_send_IPI_allbutself(NMI_VECTOR)
                                                        // NMI interrupt, dead loop
                                                        crash_nmi_callback
  printk_safe_flush_on_panic
    printk_safe_flush
      __printk_safe_flush
        // deadlock
        raw_spin_lock_irqsave(&read_lock)

DEADLOCK: read_lock is taken on CPU1 and will never get released.

It happens when panic() stops a CPU by NMI while it has been in
the middle of printk_safe_flush().

Handle the lock the same way as logbuf_lock. The printk_safe buffers
are flushed only when both locks can be safely taken. It can avoid
the deadlock _in this particular case_ at expense of losing contents
of printk_safe buffers.

Note: It would actually be safe to re-init the locks when all CPUs were
      stopped by NMI. But it would require passing this information
      from arch-specific code. It is not worth the complexity.
      Especially because logbuf_lock and printk_safe buffers have been
      obsoleted by the lockless ring buffer.

Fixes: cf9b1106 ("printk/nmi: flush NMI messages on the system panic")
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: <stable@vger.kernel.org>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210210034823.64867-1-songmuchun@bytedance.com

The command 'find ./kernel/printk/ | xargs ./scripts/kernel-doc -none'
reported a mismatch with the kernel-doc of prb_rec_init_wr().

Rectify the kernel-doc, such that no issues remain for ./kernel/printk/.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210125081748.19903-1-lukas.bulwahn@gmail.com

Commit f0e386ee ("printk: fix buffer overflow potential for
print_text()") added string termination in record_print_text().
However it used the wrong base pointer for adding the terminator.
This led to a 0-byte being written somewhere beyond the buffer.

Use the correct base pointer when adding the terminator.

Fixes: f0e386ee ("printk: fix buffer overflow potential for print_text()")
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210124202728.4718-1-john.ogness@linutronix.de

Before the commit 896fbe20 ("printk: use the lockless
ringbuffer"), msg_print_text() would only write up to size-1 bytes
into the provided buffer. Some callers expect this behavior and
append a terminator to returned string. In particular:

arch/powerpc/xmon/xmon.c:dump_log_buf()
arch/um/kernel/kmsg_dump.c:kmsg_dumper_stdout()

msg_print_text() has been replaced by record_print_text(), which
currently fills the full size of the buffer. This causes a
buffer overflow for the above callers.

Change record_print_text() so that it will only use size-1 bytes
for text data. Also, for paranoia sakes, add a terminator after
the text data.

And finally, document this behavior so that it is clear that only
size-1 bytes are used and a terminator is added.

Fixes: 896fbe20 ("printk: use the lockless ringbuffer")
Cc: stable@vger.kernel.org # 5.10+
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210114170412.4819-1-john.ogness@linutronix.de

kmsg_dump_get_buffer() uses @syslog to determine if the syslog
prefix should be written to the buffer. However, when calculating
the maximum number of records that can fit into the buffer, it
always counts the bytes from the syslog prefix.

Use @syslog when calculating the maximum number of records that can
fit into the buffer.

Fixes: e2ae715d ("kmsg - kmsg_dump() use iterator to receive log buffer content")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210113164413.1599-1-john.ogness@linutronix.de

Counting text lines in a record simply involves counting the number
of newline characters (+1). However, it is searching the full data
block for newline characters, even though the text data can be (and
often is) a subset of that area. Since the extra area in the data
block was never initialized, the result is that extra newlines may
be seen and counted.

Restrict newline searching to the text data length.

Fixes: b6cf8b3f ("printk: add lockless ringbuffer")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210113144234.6545-1-john.ogness@linutronix.de

This reverts commit 757055ae.

The commit caused that ttynull was used as the default console
on several systems[1][2][3]. As a result, the console was
blank even when a better alternative existed.

It happened when there was no console configured
on the command line and ttynull_init() was the first initcall
calling register_console().

Or it happened when /dev/ did not exist when console_on_rootfs()
was called. It was not able to open /dev/console even though
a console driver was registered. It tried to add ttynull console
but it obviously did not help. But ttynull became the preferred
console and was used by /dev/console when it was available later.

The commit tried to fix a historical problem that have been there
for ages. The primary motivation was the commit 3cffa06a
("printk/console: Allow to disable console output by using console=""
 or console=null"). It provided a clean solution for a workaround
 that was widely used and worked only by chance.

This revert causes that the console="" or console=null command line
options will again work only by chance. These options will cause that
a particular console will be preferred and the default (tty) ones
will not get enabled. There will be no console registered at
all. As a result there won't be stdin, stdout, and stderr for
the init process. But it worked exactly this way even before.

The proper solution has to fulfill many conditions:

  + Register ttynull only when explicitly required or as
    the ultimate fallback.

  + ttynull should get associated with /dev/console but it must
    not become preferred console when used as a fallback.
    Especially, it must still be possible to replace it
    by a better console later.

Such a change requires clean up of the register_console() code.
Otherwise, it would be even harder to follow. Especially, the use
of has_preferred_console and CON_CONSDEV flag is tricky. The clean
up is risky. The ordering of consoles is not well defined. And
any changes tend to break existing user settings.

Do the revert at the least risky solution for now.

[1] https://lore.kernel.org/linux-kselftest/20201221144302.GR4077@smile.fi.intel.com/
[2] https://lore.kernel.org/lkml/d2a3b3c0-e548-7dd1-730f-59bc5c04e191@synopsys.com/
[3] https://patchwork.ozlabs.org/project/linux-um/patch/20210105120128.10854-1-thomas@m3y3r.de/Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reported-by: Vineet Gupta <vgupta@synopsys.com>
Reported-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull gcc-plugins fix from Kees Cook:
 "Bump c++ standard version for latest GCC versions (Valdis Kletnieks)"

* tag 'gcc-plugins-v5.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  gcc-plugins: fix gcc 11 indigestion with plugins...

Pull spi fixes from Mark Brown:
 "A couple of core fixes here, both to do with handling of drivers which
  don't report their maximum speed since we factored some of the
  handling for transfer speeds out into the core in the previous
  release.

  There's also some driver specific fixes, including a relatively large
  set for some races around timeouts in spi-geni-qcom"

* tag 'spi-fix-v5.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: fix the divide by 0 error when calculating xfer waiting time
  spi: Fix the clamping of spi->max_speed_hz
  spi: altera: fix return value for altera_spi_txrx()
  spi: stm32: FIFO threshold level - fix align packet size
  spi: spi-geni-qcom: Print an error when we timeout setting the CS
  spi: spi-geni-qcom: Don't try to set CS if an xfer is pending
  spi: spi-geni-qcom: Fail new xfers if xfer/cancel/abort pending
  spi: spi-geni-qcom: Fix geni_spi_isr() NULL dereference in timeout case

Merge tag 'regulator-fix-v5.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator

Pull regulator fixes from Mark Brown:
 "A few minor driver specific fixes, mostly DT bindings document bits,
  plus a new device ID"

* tag 'regulator-fix-v5.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: qcom-rpmh: add QCOM_COMMAND_DB dependency
  regulator: qcom-rpmh-regulator: correct hfsmps515 definition
  dt-bindings: regulator: qcom,rpmh-regulator: add pm8009 revision
  regulator: bd718x7: Add enable times
  regulator: pf8x00: Use specific compatible strings for devices

Pull regmap fixes from Mark Brown:
 "A couple of small fixes for leaks when attaching a device to a
  preexisting regmap"

* tag 'regmap-fix-v5.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: debugfs: Fix a reversed if statement in regmap_debugfs_init()
  regmap: debugfs: Fix a memory leak when calling regmap_attach_dev

Fedora Rawhide has started including gcc 11,and the g++ compiler
throws a wobbly when it hits scripts/gcc-plugins:

  HOSTCXX scripts/gcc-plugins/latent_entropy_plugin.so
In file included from /usr/include/c++/11/type_traits:35,
                 from /usr/lib/gcc/x86_64-redhat-linux/11/plugin/include/system.h:244,
                 from /usr/lib/gcc/x86_64-redhat-linux/11/plugin/include/gcc-plugin.h:28,
                 from scripts/gcc-plugins/gcc-common.h:7,
                 from scripts/gcc-plugins/latent_entropy_plugin.c:78:
/usr/include/c++/11/bits/c++0x_warning.h:32:2: error: #error This file requires compiler and library support for the ISO
 C++ 2011 standard. This support must be enabled with the -std=c++11 or -std=gnu++11 compiler options.
   32 | #error This file requires compiler and library support \

In fact, it works just fine with c++11, which has been in gcc since 4.8,
and we now require 4.9 as a minimum.
Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/82487.1609006918@turing-police

Pull btrfs fixes from David Sterba:
 "A few more fixes that arrived before the end of the year:

   - a bunch of fixes related to transaction handle lifetime wrt various
     operations (umount, remount, qgroup scan, orphan cleanup)

   - async discard scheduling fixes

   - fix item size calculation when item keys collide for extend refs
     (hardlinks)

   - fix qgroup flushing from running transaction

   - fix send, wrong file path when there is an inode with a pending
     rmdir

   - fix deadlock when cloning inline extent and low on free metadata
     space"

* tag 'for-5.11-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: run delayed iputs when remounting RO to avoid leaking them
  btrfs: add assertion for empty list of transactions at late stage of umount
  btrfs: fix race between RO remount and the cleaner task
  btrfs: fix transaction leak and crash after cleaning up orphans on RO mount
  btrfs: fix transaction leak and crash after RO remount caused by qgroup rescan
  btrfs: merge critical sections of discard lock in workfn
  btrfs: fix racy access to discard_ctl data
  btrfs: fix async discard stall
  btrfs: tests: initialize test inodes location
  btrfs: send: fix wrong file path when there is an inode with a pending rmdir
  btrfs: qgroup: don't try to wait flushing if we're already holding a transaction
  btrfs: correctly calculate item size used when item key collision happens
  btrfs: fix deadlock when cloning inline extent and low on free metadata space

Pull vhost bugfix from Michael Tsirkin:
 "This fixes configs with vhost vsock behind a viommu"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost/vsock: add IOTLB API support

Pull sound fixes from Takashi Iwai:
 "Here is a collection of USB- and HD-audio fixes.

  Most of them are device-specific quirks while one fix is for a
  regression due to an incorrect mutex unlock introduced in this merge
  window"

* tag 'sound-5.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda/via: Fix runtime PM for Clevo W35xSS
  ALSA: usb-audio: Add quirk for RC-505
  ALSA: hda/hdmi: Fix incorrect mutex unlock in silent_stream_disable()
  ALSA: hda/realtek: Enable mute and micmute LED on HP EliteBook 850 G7
  ALSA: hda/realtek: Add two "Intel Reference board" SSID in the ALC256.
  ALSA: hda/realtek: Add mute LED quirk for more HP laptops
  ALSA: hda/conexant: add a new hda codec CX11970
  ALSA: usb-audio: Add quirk for BOSS AD-10
  ALSA: usb-audio: Fix UBSAN warnings for MIDI jacks
  ALSA: hda/realtek - Modify Dell platform name
  ALSA: hda/realtek - Fix speaker volume control on Lenovo C940

Pull ARC updates from Vineet Gupta:
 "Things are quieter on upstreaming front as we are mostly focusing on
  ARCv3/ARC64 port.

  This contains just build system updates from Masahiro Yamada"

* tag 'arc-5.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: build: use $(READELF) instead of hard-coded readelf
  ARC: build: remove unneeded extra-y
  ARC: build: move symlink creation to arch/arc/Makefile to avoid race
  ARC: build: add boot_targets to PHONY
  ARC: build: add uImage.lzma to the top-level target
  ARC: build: remove non-existing bootpImage from KBUILD_IMAGE

Pull networking fixes from Jakub Kicinski:
 "Networking fixes, including fixes from netfilter, wireless and bpf
  trees.

  Current release - regressions:

   - mt76: fix NULL pointer dereference in mt76u_status_worker and
     mt76s_process_tx_queue

   - net: ipa: fix interconnect enable bug

  Current release - always broken:

   - netfilter: fixes possible oops in mtype_resize in ipset

   - ath11k: fix number of coding issues found by static analysis tools
     and spurious error messages

  Previous releases - regressions:

   - e1000e: re-enable s0ix power saving flows for systems with the
     Intel i219-LM Ethernet controllers to fix power use regression

   - virtio_net: fix recursive call to cpus_read_lock() to avoid a
     deadlock

   - ipv4: ignore ECN bits for fib lookups in fib_compute_spec_dst()

   - sysfs: take the rtnl lock around XPS configuration

   - xsk: fix memory leak for failed bind and rollback reservation at
     NETDEV_TX_BUSY

   - r8169: work around power-saving bug on some chip versions

  Previous releases - always broken:

   - dcb: validate netlink message in DCB handler

   - tun: fix return value when the number of iovs exceeds MAX_SKB_FRAGS
     to prevent unnecessary retries

   - vhost_net: fix ubuf refcount when sendmsg fails

   - bpf: save correct stopping point in file seq iteration

   - ncsi: use real net-device for response handler

   - neighbor: fix div by zero caused by a data race (TOCTOU)

   - bareudp: fix use of incorrect min_headroom size and a false
     positive lockdep splat from the TX lock

   - mvpp2:
      - clear force link UP during port init procedure in case
        bootloader had set it
      - add TCAM entry to drop flow control pause frames
      - fix PPPoE with ipv6 packet parsing
      - fix GoP Networking Complex Control config of port 3
      - fix pkt coalescing IRQ-threshold configuration

   - xsk: fix race in SKB mode transmit with shared cq

   - ionic: account for vlan tag len in rx buffer len

   - stmmac: ignore the second clock input, current clock framework does
     not handle exclusive clock use well, other drivers may reconfigure
     the second clock

  Misc:

   - ppp: change PPPIOCUNBRIDGECHAN ioctl request number to follow
     existing scheme"

* tag 'net-5.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (99 commits)
  net: dsa: lantiq_gswip: Fix GSWIP_MII_CFG(p) register access
  net: dsa: lantiq_gswip: Enable GSWIP_MII_CFG_EN also for internal PHYs
  net: lapb: Decrease the refcount of "struct lapb_cb" in lapb_device_event
  r8169: work around power-saving bug on some chip versions
  net: usb: qmi_wwan: add Quectel EM160R-GL
  selftests: mlxsw: Set headroom size of correct port
  net: macb: Correct usage of MACB_CAPS_CLK_HW_CHG flag
  ibmvnic: fix: NULL pointer dereference.
  docs: networking: packet_mmap: fix old config reference
  docs: networking: packet_mmap: fix formatting for C macros
  vhost_net: fix ubuf refcount incorrectly when sendmsg fails
  bareudp: Fix use of incorrect min_headroom size
  bareudp: set NETIF_F_LLTX flag
  net: hdlc_ppp: Fix issues when mod_timer is called while timer is running
  atlantic: remove architecture depends
  erspan: fix version 1 check in gre_parse_header()
  net: hns: fix return value check in __lb_other_process()
  net: sched: prevent invalid Scell_log shift count
  net: neighbor: fix a crash caused by mod zero
  ipv4: Ignore ECN bits for fib lookups in fib_compute_spec_dst()
  ...

Pull AFS fixes from David Howells:
 "Two fixes.

  The first is the fix for the strnlen() array limit check and the
  second fixes the calculation of the number of dirent records used to
  represent any particular filename length"

* tag 'afs-fixes-04012021' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Fix directory entry size calculation
  afs: Work around strnlen() oops with CONFIG_FORTIFIED_SOURCE=y

Ever since commit 2a9127fc ("mm: rewrite wait_on_page_bit_common()
logic") we've had some very occasional reports of BUG_ON(PageWriteback)
in write_cache_pages(), which we thought we already fixed in commit
073861ed ("mm: fix VM_BUG_ON(PageTail) and BUG_ON(PageWriteback)").

But syzbot just reported another one, even with that commit in place.

And it turns out that there's a simpler way to trigger the BUG_ON() than
the one Hugh found with page re-use.  It all boils down to the fact that
the page writeback is ostensibly serialized by the page lock, but that
isn't actually really true.

Yes, the people _setting_ writeback all do so under the page lock, but
the actual clearing of the bit - and waking up any waiters - happens
without any page lock.

This gives us this fairly simple race condition:

  CPU1 = end previous writeback
  CPU2 = start new writeback under page lock
  CPU3 = write_cache_pages()

  CPU1          CPU2            CPU3
  ----          ----            ----

  end_page_writeback()
    test_clear_page_writeback(page)
    ... delayed...

                lock_page();
                set_page_writeback()
                unlock_page()

                                lock_page()
                                wait_on_page_writeback();

    wake_up_page(page, PG_writeback);
    .. wakes up CPU3 ..

                                BUG_ON(PageWriteback(page));

where the BUG_ON() happens because we woke up the PG_writeback bit
becasue of the _previous_ writeback, but a new one had already been
started because the clearing of the bit wasn't actually atomic wrt the
actual wakeup or serialized by the page lock.

The reason this didn't use to happen was that the old logic in waiting
on a page bit would just loop if it ever saw the bit set again.

The nice proper fix would probably be to get rid of the whole "wait for
writeback to clear, and then set it" logic in the writeback path, and
replace it with an atomic "wait-to-set" (ie the same as we have for page
locking: we set the page lock bit with a single "lock_page()", not with
"wait for lock bit to clear and then set it").

However, out current model for writeback is that the waiting for the
writeback bit is done by the generic VFS code (ie write_cache_pages()),
but the actual setting of the writeback bit is done much later by the
filesystem ".writepages()" function.

IOW, to make the writeback bit have that same kind of "wait-to-set"
behavior as we have for page locking, we'd have to change our roughly
~50 different writeback functions.  Painful.

Instead, just make "wait_on_page_writeback()" loop on the very unlikely
situation that the PG_writeback bit is still set, basically re-instating
the old behavior.  This is very non-optimal in case of contention, but
since we only ever set the bit under the page lock, that situation is
controlled.

Reported-by: syzbot+2fc0712f8f8b8b8fa0ef@syzkaller.appspotmail.com
Fixes: 2a9127fc ("mm: rewrite wait_on_page_bit_common() logic")
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This code will leak "map->debugfs_name" because the if statement is
reversed so it only frees NULL pointers instead of non-NULL.  In
fact the if statement is not required and should just be removed
because kfree() accepts NULL pointers.

Fixes: cffa4b21 ("regmap: debugfs: Fix a memory leak when calling regmap_attach_dev")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/X/RQpfAwRdLg0GqQ@mwandaSigned-off-by: Mark Brown <broonie@kernel.org>

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) Missing sanitization of rateest userspace string, bug has been
   triggered by syzbot, patch from Florian Westphal.

2) Report EOPNOTSUPP on missing set features in nft_dynset, otherwise
   error reporting to userspace via EINVAL is misleading since this is
   reserved for malformed netlink requests.

3) New binaries with old kernels might silently accept several set
   element expressions. New binaries set on the NFT_SET_EXPR and
   NFT_DYNSET_F_EXPR flags to request for several expressions per
   element, hence old kernels which do not support for this bail out
   with EOPNOTSUPP.

* git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf:
  netfilter: nftables: add set expression flags
  netfilter: nft_dynset: report EOPNOTSUPP on missing set feature
  netfilter: xt_RATEEST: reject non-null terminated string from userspace
====================

Link: https://lore.kernel.org/r/20210103192920.18639-1-pablo@netfilter.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Martin Blumenstingl says:

====================
net: dsa: lantiq_gswip: two fixes for -net/-stable

While testing the lantiq_gswip driver in OpenWrt at least one board had
a non-working Ethernet port connected to an internal 100Mbit/s PHY22F
GPHY. The problem which could be observed:
- the PHY would detect the link just fine
- ethtool stats would see the TX counter rise
- the RX counter in ethtool was stuck at zero

It turns out that two independent patches are needed to fix this:
- first we need to enable the MII data lines also for internal PHYs
- second we need to program the GSWIP_MII_CFG registers for all ports
  except the CPU port

These two patches have also been tested by back-porting them on top of
Linux 5.4.86 in OpenWrt.

Special thanks to Hauke for debugging and brainstorming this on IRC
with me!
====================

Link: https://lore.kernel.org/r/20210103012544.3259029-1-martin.blumenstingl@googlemail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

There is one GSWIP_MII_CFG register for each switch-port except the CPU
port. The register offset for the first port is 0x0, 0x02 for the
second, 0x04 for the third and so on.

Update the driver to not only restrict the GSWIP_MII_CFG registers to
ports 0, 1 and 5. Handle ports 0..5 instead but skip the CPU port. This
means we are not overwriting the configuration for the third port (port
two since we start counting from zero) with the settings for the sixth
port (with number five) anymore.

The GSWIP_MII_PCDU(p) registers are not updated because there's really
only three (one for each of the following ports: 0, 1, 5).

Fixes: 14fceff4 ("net: dsa: Add Lantiq / Intel DSA driver for vrx200")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Enable GSWIP_MII_CFG_EN also for internal PHYs to make traffic flow.
Without this the PHY link is detected properly and ethtool statistics
for TX are increasing but there's no RX traffic coming in.

Fixes: 14fceff4 ("net: dsa: Add Lantiq / Intel DSA driver for vrx200")
Suggested-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

In lapb_device_event, lapb_devtostruct is called to get a reference to
an object of "struct lapb_cb". lapb_devtostruct increases the refcount
of the object and returns a pointer to it. However, we didn't decrease
the refcount after we finished using the pointer. This patch fixes this
problem.

Fixes: a4989fa9 ("net/lapb: support netdev events")
Cc: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Xie He <xie.he.0141@gmail.com>
Link: https://lore.kernel.org/r/20201231174331.64539-1-xie.he.0141@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

A user reported failing network with RTL8168dp (a quite rare chip
version). Realtek confirmed that few chip versions suffer from a PLL
power-down hw bug.

Fixes: 07df5bd8 ("r8169: power down chip in probe")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/a1c39460-d533-7f9e-fa9d-2b8990b02426@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

New modem using ff/ff/30 for QCDM, ff/00/00 for  AT and NMEA,
and ff/ff/ff for RMNET/QMI.

T: Bus=02 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=5000 MxCh= 0
D: Ver= 3.20 Cls=ef(misc ) Sub=02 Prot=01 MxPS= 9 #Cfgs= 1
P: Vendor=2c7c ProdID=0620 Rev= 4.09
S: Manufacturer=Quectel
S: Product=EM160R-GL
S: SerialNumber=e31cedc1
C:* #Ifs= 5 Cfg#= 1 Atr=a0 MxPwr=896mA
I:* If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=30 Driver=(none)
E: Ad=81(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
E: Ad=01(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=(none)
E: Ad=83(I) Atr=03(Int.) MxPS= 10 Ivl=32ms
E: Ad=82(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
E: Ad=02(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
I:* If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=(none)
E: Ad=85(I) Atr=03(Int.) MxPS= 10 Ivl=32ms
E: Ad=84(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
E: Ad=03(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
I:* If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=(none)
E: Ad=87(I) Atr=03(Int.) MxPS= 10 Ivl=32ms
E: Ad=86(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
E: Ad=04(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
I:* If#= 4 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
E: Ad=88(I) Atr=03(Int.) MxPS= 8 Ivl=32ms
E: Ad=8e(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
E: Ad=0f(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Link: https://lore.kernel.org/r/20201230152451.245271-1-bjorn@mork.noSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The test was setting the headroom size of the wrong port. This was not
visible because of a firmware bug that canceled this bug.

Set the headroom size of the correct port, so that the test will pass
with both old and new firmware versions.

Fixes: bfa80478 ("selftests: mlxsw: Add a PFC test")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Link: https://lore.kernel.org/r/20201230114251.394009-1-idosch@idosch.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

A new flag MACB_CAPS_CLK_HW_CHG was added and all callers of
macb_set_tx_clk were gated on the presence of this flag.

-   if (!clk)
+ if (!bp->tx_clk || !(bp->caps & MACB_CAPS_CLK_HW_CHG))

However the flag was not added to anything other than the new
sama7g5_gem, turning that function call into a no op for all other
systems. This breaks the networking on Zynq.

The commit message adding this states: a new capability so that
macb_set_tx_clock() to not be called for IPs having this
capability

This strongly implies that present of the flag was intended to skip
the function not absence of the flag. Update the if statement to
this effect, which repairs the existing users.

Fixes: daafa1d3 ("net: macb: add capability to not set the clock rate")
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20210104103802.13091-1-ckeepax@opensource.cirrus.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The error is due to dereference a null pointer in function
reset_one_sub_crq_queue():

if (!scrq) {
    netdev_dbg(adapter->netdev,
               "Invalid scrq reset. irq (%d) or msgs(%p).\n",
		scrq->irq, scrq->msgs);
		return -EINVAL;
}

If the expression is true, scrq must be a null pointer and cannot
dereference.

Fixes: 9281cf2d ("ibmvnic: avoid memset null scrq msgs")
Signed-off-by: YANG LI <abaci-bugfix@linux.alibaba.com>
Reported-by: Abaci <abaci@linux.alibaba.com>
Acked-by: Lijun Pan <ljp@linux.ibm.com>
Link: https://lore.kernel.org/r/1609312994-121032-1-git-send-email-abaci-bugfix@linux.alibaba.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Before commit 889b8f96 ("packet: Kill CONFIG_PACKET_MMAP.") there
used to be a CONFIG_PACKET_MMAP config symbol that depended on
CONFIG_PACKET. The text still implies that PACKET_MMAP can be disabled.
Remove that from the text, as well as reference to old kernel versions.

Also, drop reference to broken link to information for pre 2.6.5
kernels.

Make a slight working improvement (s/In/On/) while at it.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Link: https://lore.kernel.org/r/80089f3783372c8fd7833f28ce774a171b2ef252.1609232919.git.baruch@tkos.co.ilSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The citation of macro definitions should appear in a code block.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Link: https://lore.kernel.org/r/5cb47005e7a59b64299e038827e295822193384c.1609232919.git.baruch@tkos.co.ilSigned-off-by: Jakub Kicinski <kuba@kernel.org>