Some assembler symbols are not kprobe safe, such as handle_syscall (used
as syscall exception handler), *memset*/*memcpy*/*memmove* (may cause
recursive exceptions), they can not be instrumented, just blacklist them
for kprobing.

Here is a related problem and discussion:
Link: https://lore.kernel.org/lkml/20230114143859.7ccc45c1c5d9ce302113ab0a@kernel.org/Tested-by: Jeff Xie <xiehuan09@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Add kprobe_ftrace_handler() and arch_prepare_kprobe_ftrace() to support
kprobes on ftrace, the code is similar with x86 and riscv.

Here is a simple example:

  # echo 'p:myprobe kernel_clone' > /sys/kernel/debug/tracing/kprobe_events
  # echo 'r:myretprobe kernel_clone $retval' >> /sys/kernel/debug/tracing/kprobe_events
  # echo 1 > /sys/kernel/debug/tracing/events/kprobes/myprobe/enable
  # echo 1 > /sys/kernel/debug/tracing/events/kprobes/myretprobe/enable
  # echo 1 > /sys/kernel/debug/tracing/tracing_on
  # cat /sys/kernel/debug/tracing/trace
  # tracer: nop
  #
  # entries-in-buffer/entries-written: 2/2   #P:4
  #
  #                                _-----=> irqs-off/BH-disabled
  #                               / _----=> need-resched
  #                              | / _---=> hardirq/softirq
  #                              || / _--=> preempt-depth
  #                              ||| / _-=> migrate-disable
  #                              |||| /     delay
  #           TASK-PID     CPU#  |||||  TIMESTAMP  FUNCTION
  #              | |         |   |||||     |         |
              bash-488     [002] .....  2041.190681: myprobe: (kernel_clone+0x0/0x40c)
              bash-488     [002] .....  2041.190788: myretprobe: (__do_sys_clone+0x84/0xb8 <- kernel_clone) arg1=0x200
Tested-by: Jeff Xie <xiehuan09@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Use the generic kretprobe trampoline handler to add kretprobes support
for LoongArch.
Tested-by: Jeff Xie <xiehuan09@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Kprobes allows you to trap at almost any kernel address and execute a
callback function, this commit adds kprobes support for LoongArch.
Tested-by: Jeff Xie <xiehuan09@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

According to LoongArch Reference Manual, simulate branch and PC*
instructions, this is preparation for later patch.

Link: https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#branch-instructions
Link: https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#_pcaddi_pcaddu121_pcaddu18l_pcalau12iTested-by: Jeff Xie <xiehuan09@gmail.com>
Co-developed-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Use the generic ptrace_resume code for PTRACE_SYSCALL, PTRACE_CONT,
PTRACE_KILL and PTRACE_SINGLESTEP handling. This implies defining
arch_has_single_step() and implementing the user_enable_single_step()
and user_disable_single_step() functions.

LoongArch cannot do hardware single-stepping per se, the hardware
single-stepping it is achieved by configuring the instruction fetch
watchpoints (FWPS) and specifies that the next instruction must trigger
the watch exception by setting the mask bit. In some scenarios
CSR.FWPS.Skip is used to ignore the next hit result, avoid endless
repeated triggering of the same watchpoint without canceling it.
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Add regs_get_argument() which returns N th argument of the function
call, This enables ftrace kprobe events to access kernel function
arguments via $argN syntax for later use.

E.g.:
echo 'p bio_add_page arg1=$arg1' > kprobe_events
bash: echo: write error: Invalid argument
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Implement the regset-based ptrace interface that exposes hardware
breakpoints to user-space debuggers to query and set instruction and
data breakpoints.
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Use perf framework to manage hardware instruction and data breakpoints.

LoongArch defines hardware watchpoint functions for instruction fetch
and memory load/store operations. After the software configures hardware
watchpoints, the processor hardware will monitor the access address of
the instruction fetch and load/store operation, and trigger an exception
of the watchpoint when it meets the conditions set by the watchpoint.

The hardware monitoring points for instruction fetching and load/store
operations each have a register for the overall configuration of all
monitoring points, a register for recording the status of all monitoring
points, and four registers required for configuration of each watchpoint
individually.
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

When the kernel crashkernel parameter is specified with just a size,
we are supposed to allocate a region from RAM to store the crashkernel,
"crashkernel=512M" would be recommended for kdump.

Fix this by lifting similar code from x86, importing it to LoongArch
with LoongArch specific parameters added. We allocate the crashkernel
region from the first 4GB of physical memory (because SWIOTLB should be
allocated below 4GB). However, LoongArch currently does not implement
crashkernel_low and crashkernel_high the same as x86.

When X is not specified, crash_base defaults to 0 (crashkernel=YM@XM).
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

This feature depends on the kernel being relocatable.

Enable using single kernel image for kdump, and then no longer need to
build two kernels (production kernel and capture kernel share a single
kernel image).

Also enable CONFIG_CRASH_DUMP in loongson3_defconfig.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

This patch adds support for relocating the kernel to a random address.

Entropy is derived from the banner, which will change every build and
random_get_entropy() which should provide additional runtime entropy.

The kernel is relocated by up to RANDOMIZE_BASE_MAX_OFFSET bytes from
its link address. Because relocation happens so early during the kernel
booting, the amount of physical memory has not yet been determined. This
means the only way to limit relocation within the available memory is
via Kconfig. So we limit the maximum value of RANDOMIZE_BASE_MAX_OFFSET
to 256M (0x10000000) because our memory layout has many holes.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Xi Ruoyao <xry111@xry111.site> # Fix compiler warnings
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

This config allows to compile kernel as PIE and to relocate it at any
virtual address at runtime: this paves the way to KASLR.

Runtime relocation is possible since relocation metadata are embedded
into the kernel.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Xi Ruoyao <xry111@xry111.site> # Use arch_initcall
Signed-off-by: Jinyang He <hejinyang@loongson.cn> # Provide la_abs relocation code
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Use the "la_abs macro" instead of the "la.abs pseudo instruction" to
prepare for the subsequent PIE kernel. When PIE is not enabled, la_abs
is equivalent to la.abs.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Add JUMP_VIRT_ADDR macro implementation to avoid using la.abs directly.
This is a preparation for subsequent patches.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Let's start to kill la.abs in preparation for the subsequent support of
the PIE kernel.

BTW, Re-tab the indention in arch/loongarch/kernel/entry.S for alignment.
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Introduce Kconfig option ARCH_STRICT_ALIGN to make -mstrict-align be
configurable.

Not all LoongArch cores support h/w unaligned access, we can use the
-mstrict-align build parameter to prevent unaligned accesses.

CPUs with h/w unaligned access support:
Loongson-2K2000/2K3000/3A5000/3C5000/3D5000.

CPUs without h/w unaligned access support:
Loongson-2K500/2K1000.

This option is enabled by default to make the kernel be able to run on
all LoongArch systems. But you can disable it manually if you want to
run kernel only on systems with h/w unaligned access support in order to
optimise for performance.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Under CONFIG_DEBUG_ATOMIC_SLEEP=y and CONFIG_DEBUG_PREEMPT=y, we can see
the following messages on LoongArch, this is because using might_sleep()
in preemption disable context.

[    0.001127] smp: Bringing up secondary CPUs ...
[    0.001222] Booting CPU#1...
[    0.001244] 64-bit Loongson Processor probed (LA464 Core)
[    0.001247] CPU1 revision is: 0014c012 (Loongson-64bit)
[    0.001250] FPU1 revision is: 00000000
[    0.001252] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:283
[    0.001255] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1
[    0.001257] preempt_count: 1, expected: 0
[    0.001258] RCU nest depth: 0, expected: 0
[    0.001259] Preemption disabled at:
[    0.001261] [<9000000000223800>] arch_dup_task_struct+0x20/0x110
[    0.001272] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.2.0-rc7+ #43
[    0.001275] Hardware name: Loongson Loongson-3A5000-7A1000-1w-A2101/Loongson-LS3A5000-7A1000-1w-A2101, BIOS vUDK2018-LoongArch-V4.0.05132-beta10 12/13/202
[    0.001277] Stack : 0072617764726148 0000000000000000 9000000000222f1c 90000001001e0000
[    0.001286]         90000001001e3be0 90000001001e3be8 0000000000000000 0000000000000000
[    0.001292]         90000001001e3be8 0000000000000040 90000001001e3cb8 90000001001e3a50
[    0.001297]         9000000001642000 90000001001e3be8 be694d10ce4139dd 9000000100174500
[    0.001303]         0000000000000001 0000000000000001 00000000ffffe0a2 0000000000000020
[    0.001309]         000000000000002f 9000000001354116 00000000056b0000 ffffffffffffffff
[    0.001314]         0000000000000000 0000000000000000 90000000014f6e90 9000000001642000
[    0.001320]         900000000022b69c 0000000000000001 0000000000000000 9000000001736a90
[    0.001325]         9000000100038000 0000000000000000 9000000000222f34 0000000000000000
[    0.001331]         00000000000000b0 0000000000000004 0000000000000000 0000000000070000
[    0.001337]         ...
[    0.001339] Call Trace:
[    0.001342] [<9000000000222f34>] show_stack+0x5c/0x180
[    0.001346] [<90000000010bdd80>] dump_stack_lvl+0x60/0x88
[    0.001352] [<9000000000266418>] __might_resched+0x180/0x1cc
[    0.001356] [<90000000010c742c>] mutex_lock+0x20/0x64
[    0.001359] [<90000000002a8ccc>] irq_find_matching_fwspec+0x48/0x124
[    0.001364] [<90000000002259c4>] constant_clockevent_init+0x68/0x204
[    0.001368] [<900000000022acf4>] start_secondary+0x40/0xa8
[    0.001371] [<90000000010c0124>] smpboot_entry+0x60/0x64

Here are the complete call chains:

smpboot_entry()
  start_secondary()
    constant_clockevent_init()
      get_timer_irq()
        irq_find_matching_fwnode()
          irq_find_matching_fwspec()
            mutex_lock()
              might_sleep()
                __might_sleep()
                  __might_resched()

In order to avoid the above issue, we should break the call chains,
using timer_irq_installed variable as check condition to only call
get_timer_irq() once in constant_clockevent_init() is a simple and
proper way.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Fix Chinese comma introduced by accident in cpu.h.
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch architecture changes for 6.3 depend on the pci changes
to work well, so merge them to create a base.

Pull x86 fix from Thomas Gleixner:
 "A single fix for x86.

  Revert the recent change to the MTRR code which aimed to support
  SEV-SNP guests on Hyper-V. It caused a regression on XEN Dom0 kernels.

  The underlying issue of MTTR (mis)handling in the x86 code needs some
  deeper investigation and is definitely not 6.2 material"

* tag 'x86-urgent-2023-02-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mtrr: Revert 90b926e6 ("x86/pat: Fix pat_x_mtrr_type() for MTRR disabled case")

Pull timer fix from Thomas Gleixner:
 "A fix for a long standing issue in the alarmtimer code.

  Posix-timers armed with a short interval with an ignored signal result
  in an unpriviledged DoS. Due to the ignored signal the timer switches
  into self rearm mode. This issue had been "fixed" before but a rework
  of the alarmtimer code 5 years ago lost that workaround.

  There is no real good solution for this issue, which is also worked
  around in the core posix-timer code in the same way, but it certainly
  moved way up on the ever growing todo list"

* tag 'timers-urgent-2023-02-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  alarmtimer: Prevent starvation by small intervals and SIG_IGN

Pull irq fix from Thomas Gleixner:
 "A single build fix for the PCI/MSI infrastructure.

  The addition of the new alloc/free interfaces in this cycle forgot to
  add stub functions for pci_msix_alloc_irq_at() and pci_msix_free_irq()
  for the CONFIG_PCI_MSI=n case"

* tag 'irq-urgent-2023-02-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  PCI/MSI: Provide missing stubs for CONFIG_PCI_MSI=n

Pull kvm/x86 fixes from Paolo Bonzini:

 - zero all padding for KVM_GET_DEBUGREGS

 - fix rST warning

 - disable vPMU support on hybrid CPUs

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm: initialize all of the kvm_debugregs structure before sending it to userspace
  perf/x86: Refuse to export capabilities for hybrid PMUs
  KVM: x86/pmu: Disable vPMU support on hybrid CPUs (host PMUs)
  Documentation/hw-vuln: Fix rST warning

Pull arm64 regression fix from Will Deacon:
 "Apologies for the _extremely_ late pull request here, but we had a
  'perf' (i.e. CPU PMU) regression on the Apple M1 reported on Wednesday
  [1] which was introduced by bd275681 ("perf: Rewrite core context
  handling") during the merge window.

  Mark and I looked into this and noticed an additional problem caused
  by the same patch, where the 'CHAIN' event (used to combine two
  adjacent 32-bit counters into a single 64-bit counter) was not being
  filtered correctly. Mark posted a series on Thursday [2] which
  addresses both of these regressions and I queued it the same day.

  The changes are small, self-contained and have been confirmed to fix
  the original regression.

  Summary:

   - Fix 'perf' regression for non-standard CPU PMU hardware (i.e. Apple
     M1)"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: perf: reject CHAIN events at creation time
  arm_pmu: fix event CPU filtering

Pull block fix from Jens Axboe:
 "I guess this is what can happen when you prep things early for going
  away, something else comes in last minute. This one fixes another
  regression in 6.2 for NVMe, from this release, and hence we should
  probably get it submitted for 6.2.

  Still waiting for the original reporter (see bugzilla linked in the
  commit) to test this, but Keith managed to setup and recreate the
  issue and tested the patch that way"

* tag 'block-6.2-2023-02-17' of git://git.kernel.dk/linux:
  nvme-pci: refresh visible attrs for cmb attributes

Merge tag 'mm-hotfixes-stable-2023-02-17-15-16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "Six hotfixes. Five are cc:stable: four for MM, one for nilfs2.

  Also a MAINTAINERS update"

* tag 'mm-hotfixes-stable-2023-02-17-15-16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  nilfs2: fix underflow in second superblock position calculations
  hugetlb: check for undefined shift on 32 bit architectures
  mm/migrate: fix wrongly apply write bit after mkdirty on sparc64
  MAINTAINERS: update FPU EMULATOR web page
  mm/MADV_COLLAPSE: set EAGAIN on unexpected page refcount
  mm/filemap: fix page end in filemap_get_read_batch

Macro NILFS_SB2_OFFSET_BYTES, which computes the position of the second
superblock, underflows when the argument device size is less than 4096
bytes.  Therefore, when using this macro, it is necessary to check in
advance that the device size is not less than a lower limit, or at least
that underflow does not occur.

The current nilfs2 implementation lacks this check, causing out-of-bound
block access when mounting devices smaller than 4096 bytes:

 I/O error, dev loop0, sector 36028797018963960 op 0x0:(READ) flags 0x0
 phys_seg 1 prio class 2
 NILFS (loop0): unable to read secondary superblock (blocksize = 1024)

In addition, when trying to resize the filesystem to a size below 4096
bytes, this underflow occurs in nilfs_resize_fs(), passing a huge number
of segments to nilfs_sufile_resize(), corrupting parameters such as the
number of segments in superblocks.  This causes excessive loop iterations
in nilfs_sufile_resize() during a subsequent resize ioctl, causing
semaphore ns_segctor_sem to block for a long time and hang the writer
thread:

 INFO: task segctord:5067 blocked for more than 143 seconds.
      Not tainted 6.2.0-rc8-syzkaller-00015-gf6feea56 #0
 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
 task:segctord        state:D stack:23456 pid:5067  ppid:2
 flags:0x00004000
 Call Trace:
  <TASK>
  context_switch kernel/sched/core.c:5293 [inline]
  __schedule+0x1409/0x43f0 kernel/sched/core.c:6606
  schedule+0xc3/0x190 kernel/sched/core.c:6682
  rwsem_down_write_slowpath+0xfcf/0x14a0 kernel/locking/rwsem.c:1190
  nilfs_transaction_lock+0x25c/0x4f0 fs/nilfs2/segment.c:357
  nilfs_segctor_thread_construct fs/nilfs2/segment.c:2486 [inline]
  nilfs_segctor_thread+0x52f/0x1140 fs/nilfs2/segment.c:2570
  kthread+0x270/0x300 kernel/kthread.c:376
  ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
  </TASK>
 ...
 Call Trace:
  <TASK>
  folio_mark_accessed+0x51c/0xf00 mm/swap.c:515
  __nilfs_get_page_block fs/nilfs2/page.c:42 [inline]
  nilfs_grab_buffer+0x3d3/0x540 fs/nilfs2/page.c:61
  nilfs_mdt_submit_block+0xd7/0x8f0 fs/nilfs2/mdt.c:121
  nilfs_mdt_read_block+0xeb/0x430 fs/nilfs2/mdt.c:176
  nilfs_mdt_get_block+0x12d/0xbb0 fs/nilfs2/mdt.c:251
  nilfs_sufile_get_segment_usage_block fs/nilfs2/sufile.c:92 [inline]
  nilfs_sufile_truncate_range fs/nilfs2/sufile.c:679 [inline]
  nilfs_sufile_resize+0x7a3/0x12b0 fs/nilfs2/sufile.c:777
  nilfs_resize_fs+0x20c/0xed0 fs/nilfs2/super.c:422
  nilfs_ioctl_resize fs/nilfs2/ioctl.c:1033 [inline]
  nilfs_ioctl+0x137c/0x2440 fs/nilfs2/ioctl.c:1301
  ...

This fixes these issues by inserting appropriate minimum device size
checks or anti-underflow checks, depending on where the macro is used.

Link: https://lkml.kernel.org/r/0000000000004e1dfa05f4a48e6b@google.com
Link: https://lkml.kernel.org/r/20230214224043.24141-1-konishi.ryusuke@gmail.comSigned-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: <syzbot+f0c4082ce5ebebdac63b@syzkaller.appspotmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Users can specify the hugetlb page size in the mmap, shmget and
memfd_create system calls.  This is done by using 6 bits within the flags
argument to encode the base-2 logarithm of the desired page size.  The
routine hstate_sizelog() uses the log2 value to find the corresponding
hugetlb hstate structure.  Converting the log2 value (page_size_log) to
potential hugetlb page size is the simple statement:

	1UL << page_size_log

Because only 6 bits are used for page_size_log, the left shift can not be
greater than 63.  This is fine on 64 bit architectures where a long is 64
bits.  However, if a value greater than 31 is passed on a 32 bit
architecture (where long is 32 bits) the shift will result in undefined
behavior.  This was generally not an issue as the result of the undefined
shift had to exactly match hugetlb page size to proceed.

Recent improvements in runtime checking have resulted in this undefined
behavior throwing errors such as reported below.

Fix by comparing page_size_log to BITS_PER_LONG before doing shift.

Link: https://lkml.kernel.org/r/20230216013542.138708-1-mike.kravetz@oracle.com
Link: https://lore.kernel.org/lkml/CA+G9fYuei_Tr-vN9GS7SfFyU1y9hNysnf=PB7kT0=yv4MiPgVg@mail.gmail.com/
Fixes: 42d7395f ("mm: support more pagesizes for MAP_HUGETLB/SHM_HUGETLB")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reviewed-by: Jesper Juhl <jesperjuhl76@gmail.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Nick Bowler reported another sparc64 breakage after the young/dirty
persistent work for page migration (per "Link:" below).  That's after a
similar report [2].

It turns out page migration was overlooked, and it wasn't failing before
because page migration was not enabled in the initial report test
environment.

David proposed another way [2] to fix this from sparc64 side, but that
patch didn't land somehow.  Neither did I check whether there's any other
arch that has similar issues.

Let's fix it for now as simple as moving the write bit handling to be
after dirty, like what we did before.

Note: this is based on mm-unstable, because the breakage was since 6.1 and
we're at a very late stage of 6.2 (-rc8), so I assume for this specific
case we should target this at 6.3.

[1] https://lore.kernel.org/all/20221021160603.GA23307@u164.east.ru/
[2] https://lore.kernel.org/all/20221212130213.136267-1-david@redhat.com/

Link: https://lkml.kernel.org/r/20230216153059.256739-1-peterx@redhat.com
Fixes: 2e346877 ("mm: remember young/dirty bit for page migrations")
Link: https://lore.kernel.org/all/CADyTPExpEqaJiMGoV+Z6xVgL50ZoMJg49B10LcZ=8eg19u34BA@mail.gmail.com/Signed-off-by: Peter Xu <peterx@redhat.com>
Reported-by: Nick Bowler <nbowler@draconx.ca>
Acked-by: David Hildenbrand <david@redhat.com>
Tested-by: Nick Bowler <nbowler@draconx.ca>
Cc: <regressions@lists.linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Pull powerpc fix from Michael Ellerman:

 - Prevent fallthrough to hash TLB flush when using radix

Thanks to Benjamin Gray and Erhard Furtner.

* tag 'powerpc-6.2-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Prevent fallthrough to hash TLB flush when using radix

Pull NFS client fix from Trond Myklebust:
 "Unfortunately, we found another bug in the NFSv4.2 READ_PLUS code.

  Since it has not been possible to fix the bug in time for the 6.2
  release, let's just revert the Kconfig change that enables it:

   - Revert 'NFSv4.2: Change the default KConfig value for READ_PLUS'"

* tag 'nfs-for-6.2-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  Revert "NFSv4.2: Change the default KConfig value for READ_PLUS"

Pull sound fixes from Takashi Iwai:
 "A few last-minute fixes. The significant ones are two ASoC SOF
  regression fixes while the rest are trivial HD-audio quirks.

  All are small / one-liners and should be pretty safe to take"

* tag 'sound-fix-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ASoC: SOF: Intel: hda-dai: fix possible stream_tag leak
  ALSA: hda/realtek: Enable mute/micmute LEDs and speaker support for HP Laptops
  ALSA: hda/realtek: fix mute/micmute LEDs don't work for a HP platform.
  ALSA: hda/realtek - fixed wrong gpio assigned
  ALSA: hda: Fix codec device field initializan
  ALSA: hda/conexant: add a new hda codec SN6180
  ASoC: SOF: ops: refine parameters order in function snd_sof_dsp_update8

Pull gpio fix from Bartosz Golaszewski:

 - fix a memory leak in gpio-sim that was triggered every time libgpiod
   tests are run in user-space

* tag 'gpio-fixes-for-v6.2-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
  gpio: sim: fix a memory leak

Pull ata fixes from Damien Le Moal:
 "Three small fixes for 6.2 final:

   - Disable READ LOG DMA EXT for Samsung MZ7LH drives as these drives
     choke on that command, from Patrick.

   - Add Intel Tiger Lake UP{3,4} to the list of supported AHCI
     controllers (this is not technically a bug fix, but it is trivial
     enough that I add it here), from Simon.

   - Fix code comments in the pata_octeon_cf driver as incorrect
     formatting was causing warnings from kernel-doc, from Randy"

* tag 'ata-6.2-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata:
  ata: pata_octeon_cf: drop kernel-doc notation
  ata: ahci: Add Tiger Lake UP{3,4} AHCI controller
  ata: libata-core: Disable READ LOG DMA EXT for Samsung MZ7LH

Pull MMC fixes from Ulf Hansson:
 "MMC core:
   - Fix potential resource leaks in SDIO card detection error path

  MMC host:
   - jz4740: Decrease maximum clock rate to workaround bug on JZ4760(B)
   - meson-gx: Fix SDIO support to get some WiFi modules to work again
   - mmc_spi: Fix error handling in ->probe()"

* tag 'mmc-v6.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: jz4740: Work around bug on JZ4760(B)
  mmc: mmc_spi: fix error handling in mmc_spi_probe()
  mmc: sdio: fix possible resource leaks in some error paths
  mmc: meson-gx: fix SDIO mode if cap_sdio_irq isn't set

Pull scheduler fixes from Ingo Molnar:

 - Fix user-after-free bug in call_usermodehelper_exec()

 - Fix missing user_cpus_ptr update in __set_cpus_allowed_ptr_locked()

 - Fix PSI use-after-free bug in ep_remove_wait_queue()

* tag 'sched-urgent-2023-02-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/psi: Fix use-after-free in ep_remove_wait_queue()
  sched/core: Fix a missed update of user_cpus_ptr
  freezer,umh: Fix call_usermode_helper_exec() vs SIGKILL

Pull NVMe fix from Christoph:

"nvme fix for Linux 6.2

 - fix visibility of the CMB sysfs attributes (Keith Busch)"

* tag 'nvme-6.2-2022-02-17' of git://git.infradead.org/nvme:
  nvme-pci: refresh visible attrs for cmb attributes

This reverts commit 7fd461c4.

Unfortunately, it has come to our attention that there is still a bug
somewhere in the READ_PLUS code that can result in nfsroot systems on
ARM to crash during boot.

Let's do the right thing and revert this change so we don't break
people's nfsroot setups.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>