This commit makes it clear that the reason that these sections are
historical is that smp_read_barrier_depends() is no more.  It also
removes the point about comparison operations, given that there are
other optimizations that can break address dependencies.
Suggested-by: Jonas Oberhauser <jonas.oberhauser@huaweicloud.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Andrea Parri <parri.andrea@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jade Alglave <j.alglave@ucl.ac.uk>
Cc: Luc Maranget <luc.maranget@inria.fr>
Cc: Akira Yokosawa <akiyks@gmail.com>
Cc: Daniel Lustig <dlustig@nvidia.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: <linux-arch@vger.kernel.org>
Cc: <linux-doc@vger.kernel.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.iitr10@gmail.com>

This commit adds discussion of address and data dependencies to the
beginning of rcu_dereference.rst in order to enable readers to more
easily make the connection to the Linux-kernel memory model in general
and to memory-barriers.txt in particular.
Reported-by: Jonas Oberhauser <jonas.oberhauser@huaweicloud.com>
Reported-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.iitr10@gmail.com>

Currently, the reader/updater compatibility rules for the three RCU
Tasks flavors are squished together in a single paragraph, which can
result in confusion.  This commit therefore splits them out into a list,
clearly showing the distinction between these flavors.

Link: https://lore.kernel.org/all/20231002211936.5948253e@gandalf.local.home/Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.iitr10@gmail.com>

The brief summary in the docstring for function list_next_or_null_rcu()
states that the function is supposed to provide the "first" member of a
list, whereas in truth it returns the next member.

Change the docstring so it describes what the function actually does.
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.iitr10@gmail.com>

Remove the repeated word "of" in comments.
Signed-off-by: Charles Han <hanchunchao@inspur.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.iitr10@gmail.com>

Merge tag 'kbuild-fixes-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Fix section mismatch warning messages for riscv and loongarch

 - Remove CONFIG_IA64 left-over from linux/export-internal.h

 - Fix the location of the quotes for UIMAGE_NAME

 - Fix a memory leak bug in Kconfig

* tag 'kbuild-fixes-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: fix memory leak from range properties
  kbuild: Move the single quotes for image name
  linux/export: clean up the IA-64 KSYM_FUNC macro
  modpost: fix section mismatch message for RELA

Pull irq fix from Borislav Petkov:

 - Flush the translation service tables to prevent unpredictable
   behavior on non-coherent GIC devices

* tag 'irq_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v3-its: Flush ITS tables correctly in non-coherent GIC designs

Pull x86 fixes from Borislav Petkov:

 - Ignore invalid x2APIC entries in order to not waste per-CPU data

 - Fix a back-to-back signals handling scenario when shadow stack is in
   use

 - A documentation fix

 - Add Kirill as TDX maintainer

* tag 'x86_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/acpi: Ignore invalid x2APIC entries
  x86/shstk: Delay signal entry SSP write until after user accesses
  x86/Documentation: Indent 'note::' directive for protocol version number note
  MAINTAINERS: Add Intel TDX entry

Pull timer fix from Borislav Petkov:

 - Do the push of pending hrtimers away from a CPU which is being
   offlined earlier in the offlining process in order to prevent a
   deadlock

* tag 'timers_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimers: Push pending hrtimers away from outgoing CPU earlier

Pull scheduler fixes from Borislav Petkov:

 - Fix virtual runtime calculation when recomputing a sched entity's
   weights

 - Fix wrongly rejected unprivileged poll requests to the cgroup psi
   pressure files

 - Make sure the load balancing is done by only one CPU

* tag 'sched_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix the decision for load balance
  sched: psi: fix unprivileged polling against cgroups
  sched/eevdf: Fix vruntime adjustment on reweight

Pull locking fix from Borislav Petkov:

 - Fix a hardcoded futex flags case which lead to one robust futex test
   failure

* tag 'locking_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  futex: Fix hardcoded flags

Pull perf fix from Borislav Petkov:

 - Make sure the context refcount is transferred too when migrating perf
   events

* tag 'perf_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Fix cpuctx refcounting

Pull SCSI fixes from James Bottomley:
 "Seven small fixes, six in drivers and one in sd.

  The sd fix is so large because it changes a struct pointer to a struct
  but otherwise is fairly simple"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: ufs: qcom-ufs: dt-bindings: Document the SM8650 UFS Controller
  scsi: sd: Fix sshdr use in sd_suspend_common()
  scsi: scsi_debug: Delete some bogus error checking
  scsi: scsi_debug: Fix some bugs in sdebug_error_write()
  scsi: ufs: core: Fix racing issue between ufshcd_mcq_abort() and ISR
  scsi: ufs: core: Expand MCQ queue slot to DeviceQueueDepth + 1
  scsi: qla2xxx: Fix system crash due to bad pointer access

Pull parisc fixes from Helge Deller:
 "On parisc we still sometimes need writeable stacks, e.g. if programs
  aren't compiled with gcc-14. To avoid issues with the upcoming
  systemd-254 we therefore have to disable prctl(PR_SET_MDWE) for now
  (for parisc only).

  The other two patches are minor: a bugfix for the soft power-off on
  qemu with 64-bit kernel and prefer strscpy() over strlcpy():

   - Fix power soft-off on qemu

   - Disable prctl(PR_SET_MDWE) since parisc sometimes still needs
     writeable stacks

   - Use strscpy instead of strlcpy in show_cpuinfo()"

* tag 'parisc-for-6.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  prctl: Disable prctl(PR_SET_MDWE) on parisc
  parisc/power: Fix power soft-off when running on qemu
  parisc: Replace strlcpy() with strscpy()

Pull xfs fixes from Chandan Babu:

 - Fix deadlock arising due to intent items in AIL not being cleared
   when log recovery fails

 - Fix stale data exposure bug when remapping COW fork extents to data
   fork

 - Fix deadlock when data device flush fails

 - Fix AGFL minimum size calculation

 - Select DEBUG_FS instead of XFS_DEBUG when XFS_ONLINE_SCRUB_STATS is
   selected

 - Fix corruption of log inode's extent count field when NREXT64 feature
   is enabled

* tag 'xfs-6.7-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: recovery should not clear di_flushiter unconditionally
  xfs: inode recovery does not validate the recovered inode
  xfs: fix again select in kconfig XFS_ONLINE_SCRUB_STATS
  xfs: fix internal error from AGFL exhaustion
  xfs: up(ic_sema) if flushing data device fails
  xfs: only remap the written blocks in xfs_reflink_end_cow_extent
  XFS: Update MAINTAINERS to catch all XFS documentation
  xfs: abort intent items when recovery intents fail
  xfs: factor out xfs_defer_pending_abort

Pull nfsd fixes from Chuck Lever:

 - Fix several long-standing bugs in the duplicate reply cache

 - Fix a memory leak

* tag 'nfsd-6.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  NFSD: Fix checksum mismatches in the duplicate reply cache
  NFSD: Fix "start of NFS reply" pointer passed to nfsd_cache_update()
  NFSD: Update nfsd_cache_append() to use xdr_stream
  nfsd: fix file memleak on client_opens_release

Pull smb client fixes from Steve French:

 - multichannel fixes (including a lock ordering fix and an important
   refcounting fix)

 - spnego fix

* tag '6.7-rc1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix lock ordering while disabling multichannel
  cifs: fix leak of iface for primary channel
  cifs: fix check of rc in function generate_smb3signingkey
  cifs: spnego: add ';' in HOST_KEY_LEN

systemd-254 tries to use prctl(PR_SET_MDWE) for it's MemoryDenyWriteExecute
functionality, but fails on parisc which still needs executable stacks in
certain combinations of gcc/glibc/kernel.

Disable prctl(PR_SET_MDWE) by returning -EINVAL for now on parisc, until
userspace has catched up.
Signed-off-by: Helge Deller <deller@gmx.de>
Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Sam James <sam@gentoo.org>
Closes: https://github.com/systemd/systemd/issues/29775Tested-by: Sam James <sam@gentoo.org>
Link: https://lore.kernel.org/all/875y2jro9a.fsf@gentoo.org/
Cc: <stable@vger.kernel.org> # v6.3+

Merge tag 'for-6.7/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - Various fixes for the DM delay target to address regressions
   introduced during the 6.7 merge window

 - Fixes to both DM bufio and the verity target for no-sleep mode,
   to address sleeping while atomic issues

 - Update DM crypt target in response to the treewide change that
   made MAX_ORDER inclusive

* tag 'for-6.7/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm-crypt: start allocating with MAX_ORDER
  dm-verity: don't use blocking calls from tasklets
  dm-bufio: fix no-sleep mode
  dm-delay: avoid duplicate logic
  dm-delay: fix bugs introduced by kthread mode
  dm-delay: fix a race between delay_presuspend and delay_bio

Firmware returns the physical address of the power switch,
so need to use gsc_writel() instead of direct memory access.

Fixes: d0c21947 ("parisc/power: Add power soft-off when running on qemu")
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v6.0+

strlcpy() reads the entire source buffer first. This read may exceed
the destination size limit. This is both inefficient and can lead
to linear read overflows if a source string is not NUL-terminated[1].
Additionally, it returns the size of the source string, not the
resulting size of the destination string. In an effort to remove strlcpy()
completely[2], replace strlcpy() here with strscpy().

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [1]
Link: https://github.com/KSPP/linux/issues/89 [2]
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Azeem Shaikh <azeemshaikh38@gmail.com>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Helge Deller <deller@gmx.de>

Pull i2c fixes from Wolfram Sang:
 "Revert a not-working conversion to generic recovery for PXA,
  use proper IO accessors for designware, and use proper PM level
  for ocores to allow accessing interrupt providers late"

* tag 'i2c-for-6.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: ocores: Move system PM hooks to the NOIRQ phase
  i2c: designware: Fix corrupted memory seen in the ISR
  Revert "i2c: pxa: move to generic GPIO recovery"

Pull turbostat updates from Len Brown:

 - Turbostat features are now table-driven (Rui Zhang)

 - Add support for some new platforms (Sumeet Pawnikar, Rui Zhang)

 - Gracefully run in configs when CPUs are limited (Rui Zhang, Srinivas
   Pandruvada)

 - misc minor fixes

[ This came in during the merge window, but sorting out the signed tag
  took a while, so thus the late merge   - Linus ]

* tag 'turbostat-2023.11.07' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: (86 commits)
  tools/power turbostat: version 2023.11.07
  tools/power/turbostat: bugfix "--show IPC"
  tools/power/turbostat: Add initial support for LunarLake
  tools/power/turbostat: Add initial support for ArrowLake
  tools/power/turbostat: Add initial support for GrandRidge
  tools/power/turbostat: Add initial support for SierraForest
  tools/power/turbostat: Add initial support for GraniteRapids
  tools/power/turbostat: Add MSR_CORE_C1_RES support for spr_features
  tools/power/turbostat: Move process to root cgroup
  tools/power/turbostat: Handle cgroup v2 cpu limitation
  tools/power/turbostat: Abstrct function for parsing cpu string
  tools/power/turbostat: Handle offlined CPUs in cpu_subset
  tools/power/turbostat: Obey allowed CPUs for system summary
  tools/power/turbostat: Obey allowed CPUs for primary thread/core detection
  tools/power/turbostat: Abstract several functions
  tools/power/turbostat: Obey allowed CPUs during startup
  tools/power/turbostat: Obey allowed CPUs when accessing CPU counters
  tools/power/turbostat: Introduce cpu_allowed_set
  tools/power/turbostat: Remove PC7/PC9 support on ADL/RPL
  tools/power/turbostat: Enable MSR_CORE_C1_RES on recent Intel client platforms
  ...

Pull bcachefs fixes from Kent Overstreet:
 "Lots of small fixes for minor nits and compiler warnings.

  Bigger items:

   - The six locks lost wakeup is finally fixed: six_read_trylock() was
     checking for the waiting bit before decrementing the number of
     readers - validated the fix with a torture test.

   - Fix for a memory reclaim issue: when needing to reallocate a key
     cache key, we now do our usual GFP_NOWAIT; unlock(); GFP_KERNEL
     dance.

   - Multiple deleted inodes btree fixes

   - Fix an issue in fsck, where i_nlink would be recalculated
     incorrectly for hardlinked files if a snapshot had ever been taken.

   - Kill journal pre-reservations: This is a bigger patch than I would
     normally send at this point, but it deletes code and it fixes some
     of our tests that would sporadically die with the journal getting
     stuck, and it's a performance improvement, too"

* tag 'bcachefs-2023-11-17' of https://evilpiepirate.org/git/bcachefs: (22 commits)
  bcachefs: Fix missing locking for dentry->d_parent access
  bcachefs: six locks: Fix lost wakeup
  bcachefs: Fix no_data_io mode checksum check
  bcachefs: Fix bch2_check_nlinks() for snapshots
  bcachefs: Don't decrease BTREE_ITER_MAX when LOCKDEP=y
  bcachefs: Disable debug log statements
  bcachefs: Fix missing transaction commit
  bcachefs: Fix error path in bch2_mount()
  bcachefs: Fix potential sleeping during mount
  bcachefs: Fix iterator leak in may_delete_deleted_inode()
  bcachefs: Kill journal pre-reservations
  bcachefs: Check for nonce offset inconsistency in data_update path
  bcachefs: Make sure to drop/retake btree locks before reclaim
  bcachefs: btree_trans->write_locked
  bcachefs: Run btree key cache shrinker less aggressively
  bcachefs: Split out btree_key_cache_types.h
  bcachefs: Guard against insufficient devices to create stripes
  bcachefs: Fix null ptr deref in bch2_backpointer_get_node()
  bcachefs: Fix multiple -Warray-bounds warnings
  bcachefs: Use DECLARE_FLEX_ARRAY() helper and fix multiple -Warray-bounds warnings
  ...

Merge tag 'mm-hotfixes-stable-2023-11-17-14-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "Thirteen hotfixes. Seven are cc:stable and the remainder pertain to
  post-6.6 issues or aren't considered suitable for backporting"

* tag 'mm-hotfixes-stable-2023-11-17-14-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  mm: more ptep_get() conversion
  parisc: fix mmap_base calculation when stack grows upwards
  mm/damon/core.c: avoid unintentional filtering out of schemes
  mm: kmem: drop __GFP_NOFAIL when allocating objcg vectors
  mm/damon/sysfs-schemes: handle tried region directory allocation failure
  mm/damon/sysfs-schemes: handle tried regions sysfs directory allocation failure
  mm/damon/sysfs: check error from damon_sysfs_update_target()
  mm: fix for negative counter: nr_file_hugepages
  selftests/mm: add hugetlb_fault_after_madv to .gitignore
  selftests/mm: restore number of hugepages
  selftests: mm: fix some build warnings
  selftests: mm: skip whole test instead of failure
  mm/damon/sysfs: eliminate potential uninitialized variable warning

Pull block fix from Jens Axboe:
 "Just a single fix from Christoph/Ming, fixing a case where integrity
  IO could be called without having an appropriate queue reference"

* tag 'block-6.7-2023-11-17' of git://git.kernel.dk/linux:
  blk-mq: make sure active queue usage is held for bio_integrity_prep()

Pull io_uring fix from Jens Axboe:
 "Just a single fixup for a change we made in this release, which caused
  a regression in sometimes missing fdinfo output if the SQPOLL thread
  had the lock held when fdinfo output was retrieved.

  This brings us back on par with what we had before, where just the
  main uring_lock will prevent that output. We'd love to get rid of that
  too, but that is beyond the scope of this release and will have to
  wait for 6.8"

* tag 'io_uring-6.7-2023-11-17' of git://git.kernel.dk/linux:
  io_uring/fdinfo: remove need for sqpoll lock for thread/pid retrieval

Pull drm fixes from Daniel Vetter:
 "This is a 'blast from the bast' fixes pull, because it contains a
  bunch of AGP fixes for amdgpu. Otherwise nothing out of the ordinary.

  Next week is back to Dave unless he's knocked out by some conference
  bug.

   - amdgpu: fixes all over, including a set of AGP fixes

   - nouvea: GSP + other bugfixes

   - ivpu build fix

   - lenovo legion go panel orientation quirk"

* tag 'drm-fixes-2023-11-17' of git://anongit.freedesktop.org/drm/drm: (30 commits)
  drm/amdgpu/gmc9: disable AGP aperture
  drm/amdgpu/gmc10: disable AGP aperture
  drm/amdgpu/gmc11: disable AGP aperture
  drm/amdgpu: add a module parameter to control the AGP aperture
  drm/amdgpu/gmc11: fix logic typo in AGP check
  drm/amd/display: Fix encoder disable logic
  drm/amd/display: Change the DMCUB mailbox memory location from FB to inbox
  drm/amdgpu: add and populate the port num into xgmi topology info
  drm/amd/display: Negate IPS allow and commit bits
  drm/amd/pm: Don't send unload message for reset
  drm/amdgpu: fix ras err_data null pointer issue in amdgpu_ras.c
  drm/amd/display: Clear dpcd_sink_ext_caps if not set
  drm/amd/display: Enable fast plane updates on DCN3.2 and above
  drm/amd/display: fix NULL dereference
  drm/amd/display: fix a NULL pointer dereference in amdgpu_dm_i2c_xfer()
  drm/amd/display: Add null checks for 8K60 lightup
  drm/amd/pm: Fill pcie error counters for gpu v1_4
  drm/amd/pm: Update metric table for smu v13_0_6
  drm/amdgpu: correct chunk_ptr to a pointer to chunk.
  drm/amd/display: Fix DSC not Enabled on Direct MST Sink
  ...

nfsd_cache_csum() currently assumes that the server's RPC layer has
been advancing rq_arg.head[0].iov_base as it decodes an incoming
request, because that's the way it used to work. On entry, it
expects that buf->head[0].iov_base points to the start of the NFS
header, and excludes the already-decoded RPC header.

These days however, head[0].iov_base now points to the start of the
RPC header during all processing. It no longer points at the NFS
Call header when execution arrives at nfsd_cache_csum().

In a retransmitted RPC the XID and the NFS header are supposed to
be the same as the original message, but the contents of the
retransmitted RPC header can be different. For example, for krb5,
the GSS sequence number will be different between the two. Thus if
the RPC header is always included in the DRC checksum computation,
the checksum of the retransmitted message might not match the
checksum of the original message, even though the NFS part of these
messages is identical.

The result is that, even if a matching XID is found in the DRC,
the checksum mismatch causes the server to execute the
retransmitted RPC transaction again.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

The "statp + 1" pointer that is passed to nfsd_cache_update() is
supposed to point to the start of the egress NFS Reply header. In
fact, it does point there for AUTH_SYS and RPCSEC_GSS_KRB5 requests.

But both krb5i and krb5p add fields between the RPC header's
accept_stat field and the start of the NFS Reply header. In those
cases, "statp + 1" points at the extra fields instead of the Reply.
The result is that nfsd_cache_update() caches what looks to the
client like garbage.

A connection break can occur for a number of reasons, but the most
common reason when using krb5i/p is a GSS sequence number window
underrun. When an underrun is detected, the server is obliged to
drop the RPC and the connection to force a retransmit with a fresh
GSS sequence number. The client presents the same XID, it hits in
the server's DRC, and the server returns the garbage cache entry.

The "statp + 1" argument has been used since the oldest changeset
in the kernel history repo, so it has been in nfsd_dispatch()
literally since before history began. The problem arose only when
the server-side GSS implementation was added twenty years ago.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Jeff Layton <jlayton@kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

When inserting a DRC-cached response into the reply buffer, ensure
that the reply buffer's xdr_stream is updated properly. Otherwise
the server will send a garbage response.

Cc: stable@vger.kernel.org # v6.3+
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

seq_release should be called to free the allocated seq_file

Cc: stable@vger.kernel.org # v5.3+
Signed-off-by: Mahmoud Adam <mngyadam@amazon.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Fixes: 78599c42 ("nfsd4: add file to display list of client's opens")
Reviewed-by: NeilBrown <neilb@suse.de>
Tested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Commit 23baf831 ("mm, treewide: redefine MAX_ORDER sanely")
changed the meaning of MAX_ORDER from exclusive to inclusive. So, we
can allocate compound pages with up to 1 << MAX_ORDER pages.

Reflect this change in dm-crypt and start trying to allocate compound
pages with MAX_ORDER.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

The commit 5721d4e5 enhanced dm-verity, so that it can verify blocks
from tasklets rather than from workqueues. This reportedly improves
performance significantly.

However, dm-verity was using the flag CRYPTO_TFM_REQ_MAY_SLEEP from
tasklets which resulted in warnings about sleeping function being called
from non-sleeping context.

BUG: sleeping function called from invalid context at crypto/internal.h:206
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 14, name: ksoftirqd/0
preempt_count: 100, expected: 0
RCU nest depth: 0, expected: 0
CPU: 0 PID: 14 Comm: ksoftirqd/0 Tainted: G        W 6.7.0-rc1 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x32/0x50
 __might_resched+0x110/0x160
 crypto_hash_walk_done+0x54/0xb0
 shash_ahash_update+0x51/0x60
 verity_hash_update.isra.0+0x4a/0x130 [dm_verity]
 verity_verify_io+0x165/0x550 [dm_verity]
 ? free_unref_page+0xdf/0x170
 ? psi_group_change+0x113/0x390
 verity_tasklet+0xd/0x70 [dm_verity]
 tasklet_action_common.isra.0+0xb3/0xc0
 __do_softirq+0xaf/0x1ec
 ? smpboot_thread_fn+0x1d/0x200
 ? sort_range+0x20/0x20
 run_ksoftirqd+0x15/0x30
 smpboot_thread_fn+0xed/0x200
 kthread+0xdc/0x110
 ? kthread_complete_and_exit+0x20/0x20
 ret_from_fork+0x28/0x40
 ? kthread_complete_and_exit+0x20/0x20
 ret_from_fork_asm+0x11/0x20
 </TASK>

This commit fixes dm-verity so that it doesn't use the flags
CRYPTO_TFM_REQ_MAY_SLEEP and CRYPTO_TFM_REQ_MAY_BACKLOG from tasklets. The
crypto API would do GFP_ATOMIC allocation instead, it could return -ENOMEM
and we catch -ENOMEM in verity_tasklet and requeue the request to the
workqueue.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org	# v6.0+
Fixes: 5721d4e5 ("dm verity: Add optional "try_verify_in_tasklet" feature")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm-bufio has a no-sleep mode. When activated (with the
DM_BUFIO_CLIENT_NO_SLEEP flag), the bufio client is read-only and we
could call dm_bufio_get from tasklets. This is used by dm-verity.

Unfortunately, commit 450e8dee ("dm bufio: improve concurrent IO
performance") broke this and the kernel would warn that cache_get()
was calling down_read() from no-sleeping context. The bug can be
reproduced by using "veritysetup open" with the "--use-tasklets"
flag.

This commit fixes dm-bufio, so that the tasklet mode works again, by
expanding use of the 'no_sleep_enabled' static_key to conditionally
use either a rw_semaphore or rwlock_t (which are colocated in the
buffer_tree structure using a union).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org	# v6.4
Fixes: 450e8dee ("dm bufio: improve concurrent IO performance")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

This is small refactoring of dm-delay - we avoid duplicate logic in
flush_delayed_bios and flush_delayed_bios_fast and join these two
functions into one.

We also add cond_resched() to flush_delayed_bios because the list may have
unbounded number of entries.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

This commit fixes the following bugs introduced by commit 70bbeb29
("dm delay: for short delays, use kthread instead of timers and wq"):

* the function flush_worker_fn has no exit path - on unload, this
  function will just loop and consume 100% CPU without any progress

* the wake-up mechanism in flush_worker_fn is racy - a wake up will be
  missed if the process adds entries to the delayed_bios list just
  before set_current_state(TASK_INTERRUPTIBLE)

* flush_delayed_bios_fast submits a bio while holding a global mutex;
  this may deadlock if we have multiple stacked dm-delay devices and
  the underlying device attempts to acquire the mutex too

* if the target constructor fails, it will call delay_dtr. delay_dtr
  would attempt to free dc->timer_lock without it being initialized by
  the constructor.

* if the target constructor's kthread allocation fails, delay_dtr
  would crash trying to dereference dc->worker because it is non-NULL
  due to ERR_PTR.

Fixes: 70bbeb29 ("dm delay: for short delays, use kthread instead of timers and wq")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

In delay_presuspend, we set the atomic variable may_delay and then stop
the timer and flush pending bios. The intention here is to prevent the
delay target from re-arming the timer again.

However, this test is racy. Suppose that one thread goes to delay_bio,
sees that dc->may_delay is one and proceeds; now, another thread executes
delay_presuspend, it sets dc->may_delay to zero, deletes the timer and
flushes pending bios. Then, the first thread continues and adds the bio to
delayed->list despite the fact that dc->may_delay is false.

Fix this bug by changing may_delay's type from atomic_t to bool and
only access it while holding the delayed_bios_lock mutex. Note that we
don't have to grab the mutex in delay_resume because there are no bios
in flight at this point.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

Pull overlayfs fixes from Amir Goldstein:
 "A fix to an overlayfs param parsing bug and a misformatted comment"

* tag 'ovl-fixes-6.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs:
  ovl: fix memory leak in ovl_parse_param()
  ovl: fix misformatted comment