The per-channel data is available directly in the driver data struct. So
use it without making use of pwm_[gs]et_chip_data().

The relevant change introduced by this patch to lpc18xx_pwm_disable() at
the assembler level (for an arm lpc18xx_defconfig build) is:

	push    {r3, r4, r5, lr}
	mov     r4, r0
	mov     r0, r1
	mov     r5, r1
	bl      0 <pwm_get_chip_data>
	ldr     r3, [r0, #0]

changes to

	ldr     r3, [r1, #8]
	push    {r4, lr}
	add.w   r3, r0, r3, lsl #2
	ldr     r3, [r3, #92]   ; 0x5c

So this reduces stack usage, has an improved runtime behavior because of
better pipeline usage, doesn't branch to an external function and the
generated code is a bit smaller occupying less memory.

The codesize of lpc18xx_pwm_probe() is reduced by 32 bytes.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

BPF CI fails for arm64 and s390x each with the following result:

  [...]
  All error logs:

  serial_test_kprobe_multi_bench_attach:PASS:get_syms 0 nsec
  serial_test_kprobe_multi_bench_attach:PASS:kprobe_multi_empty__open_and_load 0 nsec
  libbpf: prog 'test_kprobe_empty': failed to attach: Operation not supported
  serial_test_kprobe_multi_bench_attach:FAIL:bpf_program__attach_kprobe_multi_opts unexpected error: -95
  #92      kprobe_multi_bench_attach:FAIL
  [...]

Add the test to the deny list.

Fixes: 5b6c7e5 ("selftests/bpf: Add attach bench test")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

BPF CI fails for arm64 and s390x each with the following result:

  [...]
  All error logs:

  serial_test_kprobe_multi_bench_attach:PASS:get_syms 0 nsec
  serial_test_kprobe_multi_bench_attach:PASS:kprobe_multi_empty__open_and_load 0 nsec
  libbpf: prog 'test_kprobe_empty': failed to attach: Operation not supported
  serial_test_kprobe_multi_bench_attach:FAIL:bpf_program__attach_kprobe_multi_opts unexpected error: -95
  #92      kprobe_multi_bench_attach:FAIL
  [...]

Add the test to the deny list.

Fixes: 5b6c7e5 ("selftests/bpf: Add attach bench test")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

If track_pfn_copy() fails, we already added the dst VMA to the maple
tree. As fork() fails, we'll cleanup the maple tree, and stumble over
the dst VMA for which we neither performed any reservation nor copied
any page tables.

Consequently untrack_pfn() will see VM_PAT and try obtaining the
PAT information from the page table -- which fails because the page
table was not copied.

The easiest fix would be to simply clear the VM_PAT flag of the dst VMA
if track_pfn_copy() fails. However, the whole thing is about "simply"
clearing the VM_PAT flag is shaky as well: if we passed track_pfn_copy()
and performed a reservation, but copying the page tables fails, we'll
simply clear the VM_PAT flag, not properly undoing the reservation ...
which is also wrong.

So let's fix it properly: set the VM_PAT flag only if the reservation
succeeded (leaving it clear initially), and undo the reservation if
anything goes wrong while copying the page tables: clearing the VM_PAT
flag after undoing the reservation.

Note that any copied page table entries will get zapped when the VMA will
get removed later, after copy_page_range() succeeded; as VM_PAT is not set
then, we won't try cleaning VM_PAT up once more and untrack_pfn() will be
happy. Note that leaving these page tables in place without a reservation
is not a problem, as we are aborting fork(); this process will never run.

A reproducer can trigger this usually at the first try:

  https://gitlab.com/davidhildenbrand/scratchspace/-/raw/main/reproducers/pat_fork.c

  WARNING: CPU: 26 PID: 11650 at arch/x86/mm/pat/memtype.c:983 get_pat_info+0xf6/0x110
  Modules linked in: ...
  CPU: 26 UID: 0 PID: 11650 Comm: repro3 Not tainted 6.12.0-rc5+ #92
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:get_pat_info+0xf6/0x110
  ...
  Call Trace:
   <TASK>
   ...
   untrack_pfn+0x52/0x110
   unmap_single_vma+0xa6/0xe0
   unmap_vmas+0x105/0x1f0
   exit_mmap+0xf6/0x460
   __mmput+0x4b/0x120
   copy_process+0x1bf6/0x2aa0
   kernel_clone+0xab/0x440
   __do_sys_clone+0x66/0x90
   do_syscall_64+0x95/0x180

Likely this case was missed in:

  d155df5 ("x86/mm/pat: clear VM_PAT if copy_p4d_range failed")

... and instead of undoing the reservation we simply cleared the VM_PAT flag.

Keep the documentation of these functions in include/linux/pgtable.h,
one place is more than sufficient -- we should clean that up for the other
functions like track_pfn_remap/untrack_pfn separately.

Fixes: d155df5 ("x86/mm/pat: clear VM_PAT if copy_p4d_range failed")
Fixes: 2ab6403 ("x86: PAT: hooks in generic vm code to help archs to track pfnmap regions - v3")
Reported-by: xingwei lee <xrivendell7@gmail.com>
Reported-by: yuxin wang <wang1315768607@163.com>
Reported-by: Marius Fleischer <fleischermarius@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org
Link: https://lore.kernel.org/r/20250321112323.153741-1-david@redhat.com
Closes: https://lore.kernel.org/lkml/CABOYnLx_dnqzpCW99G81DmOr+2UzdmZMk=T3uxwNxwz+R1RAwg@mail.gmail.com/
Closes: https://lore.kernel.org/lkml/CAJg=8jwijTP5fre8woS4JVJQ8iUA6v+iNcsOgtj9Zfpc3obDOQ@mail.gmail.com/