linux-stable.git/arch/arm64/kernel/setup.c, branch v6.2

arm64: implement dynamic shadow call stack for Clang

2022-11-09T18:06:35+00:00

Implement dynamic shadow call stack support on Clang, by parsing the
unwind tables at init time to locate all occurrences of PACIASP/AUTIASP
instructions, and replacing them with the shadow call stack push and pop
instructions, respectively.

This is useful because the overhead of the shadow call stack is
difficult to justify on hardware that implements pointer authentication
(PAC), and given that the PAC instructions are executed as NOPs on
hardware that doesn't, we can just replace them without breaking
anything. As PACIASP/AUTIASP are guaranteed to be paired with respect to
manipulations of the return address, replacing them 1:1 with shadow call
stack pushes and pops is guaranteed to result in the desired behavior.

Signed-off-by: Ard Biesheuvel 
Reviewed-by: Sami Tolvanen 
Tested-by: Sami Tolvanen 
Link: https://lore.kernel.org/r/20221027155908.1940624-4-ardb@kernel.org
Signed-off-by: Will Deacon

Revert "arm64: Initialize jump labels before setup_machine_fdt()"

2022-06-15T15:14:32+00:00

This reverts commit 73e2d827a501d48dceeb5b9b267a4cd283d6b1ae.

The reverted patch was needed as a fix after commit f5bda35fba61
("random: use static branch for crng_ready()"). However, this was
already fixed by 60e5b2886b92 ("random: do not use jump labels before
they are initialized") and hence no longer necessary to initialise jump
labels before setup_machine_fdt().

Signed-off-by: Catalin Marinas

arm64: Initialize jump labels before setup_machine_fdt()

2022-06-02T19:22:48+00:00

A static key warning splat appears during early boot on arm64 systems
that credit randomness from devicetrees that contain an "rng-seed"
property. This is because setup_machine_fdt() is called before
jump_label_init() during setup_arch(). Let's swap the order of these two
calls so that jump labels are initialized before the devicetree is
unflattened and the rng seed is credited.

 static_key_enable_cpuslocked(): static key '0xffffffe51c6fcfc0' used before call to jump_label_init()
 WARNING: CPU: 0 PID: 0 at kernel/jump_label.c:166 static_key_enable_cpuslocked+0xb0/0xb8
 Modules linked in:
 CPU: 0 PID: 0 Comm: swapper Not tainted 5.18.0+ #224 44b43e377bfc84bc99bb5ab885ff694984ee09ff
 pstate: 600001c9 (nZCv dAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : static_key_enable_cpuslocked+0xb0/0xb8
 lr : static_key_enable_cpuslocked+0xb0/0xb8
 sp : ffffffe51c393cf0
 x29: ffffffe51c393cf0 x28: 000000008185054c x27: 00000000f1042f10
 x26: 0000000000000000 x25: 00000000f10302b2 x24: 0000002513200000
 x23: 0000002513200000 x22: ffffffe51c1c9000 x21: fffffffdfdc00000
 x20: ffffffe51c2f0831 x19: ffffffe51c6fcfc0 x18: 00000000ffff1020
 x17: 00000000e1e2ac90 x16: 00000000000000e0 x15: ffffffe51b710708
 x14: 0000000000000066 x13: 0000000000000018 x12: 0000000000000000
 x11: 0000000000000000 x10: 00000000ffffffff x9 : 0000000000000000
 x8 : 0000000000000000 x7 : 61632065726f6665 x6 : 6220646573752027
 x5 : ffffffe51c641d25 x4 : ffffffe51c13142c x3 : ffff0a00ffffff05
 x2 : 40000000ffffe003 x1 : 00000000000001c0 x0 : 0000000000000065
 Call trace:
  static_key_enable_cpuslocked+0xb0/0xb8
  static_key_enable+0x2c/0x40
  crng_set_ready+0x24/0x30
  execute_in_process_context+0x80/0x90
  _credit_init_bits+0x100/0x154
  add_bootloader_randomness+0x64/0x78
  early_init_dt_scan_chosen+0x140/0x184
  early_init_dt_scan_nodes+0x28/0x4c
  early_init_dt_scan+0x40/0x44
  setup_machine_fdt+0x7c/0x120
  setup_arch+0x74/0x1d8
  start_kernel+0x84/0x44c
  __primary_switched+0xc0/0xc8
 ---[ end trace 0000000000000000 ]---
 random: crng init done
 Machine model: Google Lazor (rev1 - 2) with LTE

Cc: Hsin-Yi Wang 
Cc: Douglas Anderson 
Cc: Ard Biesheuvel 
Cc: Steven Rostedt 
Cc: Jason A. Donenfeld 
Cc: Dominik Brodowski 
Fixes: f5bda35fba61 ("random: use static branch for crng_ready()")
Signed-off-by: Stephen Boyd 
Reviewed-by: Jason A. Donenfeld 
Link: https://lore.kernel.org/r/20220602022109.780348-1-swboyd@chromium.org
Signed-off-by: Catalin Marinas

arm64: Use insert_resource() to simplify code

2022-05-07T18:54:33+00:00

insert_resource() traverses the subtree layer by layer from the root node
until a proper location is found. Compared with request_resource(), the
parent node does not need to be determined in advance.

In addition, move the insertion of node 'crashk_res' into function
reserve_crashkernel() to make the associated code close together.

Signed-off-by: Zhen Lei 
Acked-by: John Donnelly  
Acked-by: Baoquan He 
Link: https://lore.kernel.org/r/20220506114402.365-3-thunder.leizhen@huawei.com
Signed-off-by: Catalin Marinas

drivers/base/node: consolidate node device subsystem initialization in node_dev_init()

2022-03-22T22:57:10+00:00

...  and call node_dev_init() after memory_dev_init() from driver_init(),
so before any of the existing arch/subsys calls.  All online nodes should
be known at that point: early during boot, arch code determines node and
zone ranges and sets the relevant nodes online; usually this happens in
setup_arch().

This is in line with memory_dev_init(), which initializes the memory
device subsystem and creates all memory block devices.

Similar to memory_dev_init(), panic() if anything goes wrong, we don't
want to continue with such basic initialization errors.

The important part is that node_dev_init() gets called after
memory_dev_init() and after cpu_dev_init(), but before any of the relevant
archs call register_cpu() to register the new cpu device under the node
device.  The latter should be the case for the current users of
topology_init().

Link: https://lkml.kernel.org/r/20220203105212.30385-1-david@redhat.com
Signed-off-by: David Hildenbrand 
Reviewed-by: Oscar Salvador 
Tested-by: Anatoly Pugachev  (sparc64)
Cc: Greg Kroah-Hartman 
Cc: Michal Hocko 
Cc: Oscar Salvador 
Cc: Mike Rapoport 
Cc: Catalin Marinas 
Cc: Will Deacon 
Cc: Thomas Bogendoerfer 
Cc: Michael Ellerman 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Paul Walmsley 
Cc: Palmer Dabbelt 
Cc: Albert Ou 
Cc: Heiko Carstens 
Cc: Vasily Gorbik 
Cc: Yoshinori Sato 
Cc: Rich Felker 
Cc: "David S. Miller" 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: "Rafael J. Wysocki" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

arm64: Use correct method to calculate nomap region boundaries

2022-01-05T14:46:06+00:00

Nomap regions are treated as "reserved". When region boundaries are not
page aligned, we usually increase the "reserved" regions rather than
decrease them. So, we should use memblock_region_reserved_base_pfn()/
memblock_region_reserved_end_pfn() instead of memblock_region_memory_
base_pfn()/memblock_region_memory_base_pfn() to calculate boundaries.

Signed-off-by: Huacai Chen 
Link: https://lore.kernel.org/r/20211022070646.41923-1-chenhuacai@loongson.cn
Signed-off-by: Catalin Marinas

arm64: Unhash early pointer print plus improve comment

2021-12-22T11:06:11+00:00

When facing a really early issue on DT parsing we have currently
a message that shows both the physical and virtual address of the FDT.
The printk pointer modifier for the virtual address shows a hashed
address there unless the user provides "no_hash_pointers" parameter in
the command-line. The situation in which this message shows-up is a bit
more serious though: the boot process is broken, nothing can be done
(even an oops is too much for this early stage) so we have this message
as a last resort in order to help debug bootloader issues, for example.
Hence, we hereby change that to "%px" in order to make debugging easy,
there's not much information leak risk in such early boot failure.

Also, we tried to improve a bit the commenting on that function, given
that if kernel fails there, it just hangs forever in a cpu_relax() loop.
The reason we cannot BUG/panic is that is too early to do so; thanks to
Mark Brown for pointing that on IRC and thanks Robin Murphy for the good
pointer hash discussion in the mailing-list.

Cc: Mark Brown 
Cc: Robin Murphy 
Signed-off-by: Guilherme G. Piccoli 
Reviewed-by: Robin Murphy 
Acked-by: Uwe Kleine-König 
Link: https://lore.kernel.org/r/20211221155230.1532850-1-gpiccoli@igalia.com
Signed-off-by: Catalin Marinas

arm64: convert to setup_initial_init_mm()

2021-07-08T18:48:21+00:00

Use setup_initial_init_mm() helper to simplify code.

Link: https://lkml.kernel.org/r/20210608083418.137226-5-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang 
Acked-by: Catalin Marinas 
Cc: Will Deacon 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'akpm' (patches from Andrew)

2021-07-02T19:08:10+00:00

Merge more updates from Andrew Morton:
 "190 patches.

  Subsystems affected by this patch series: mm (hugetlb, userfaultfd,
  vmscan, kconfig, proc, z3fold, zbud, ras, mempolicy, memblock,
  migration, thp, nommu, kconfig, madvise, memory-hotplug, zswap,
  zsmalloc, zram, cleanups, kfence, and hmm), procfs, sysctl, misc,
  core-kernel, lib, lz4, checkpatch, init, kprobes, nilfs2, hfs,
  signals, exec, kcov, selftests, compress/decompress, and ipc"

* emailed patches from Andrew Morton : (190 commits)
  ipc/util.c: use binary search for max_idx
  ipc/sem.c: use READ_ONCE()/WRITE_ONCE() for use_global_lock
  ipc: use kmalloc for msg_queue and shmid_kernel
  ipc sem: use kvmalloc for sem_undo allocation
  lib/decompressors: remove set but not used variabled 'level'
  selftests/vm/pkeys: exercise x86 XSAVE init state
  selftests/vm/pkeys: refill shadow register after implicit kernel write
  selftests/vm/pkeys: handle negative sys_pkey_alloc() return code
  selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random
  kcov: add __no_sanitize_coverage to fix noinstr for all architectures
  exec: remove checks in __register_bimfmt()
  x86: signal: don't do sas_ss_reset() until we are certain that sigframe won't be abandoned
  hfsplus: report create_date to kstat.btime
  hfsplus: remove unnecessary oom message
  nilfs2: remove redundant continue statement in a while-loop
  kprobes: remove duplicated strong free_insn_page in x86 and s390
  init: print out unknown kernel parameters
  checkpatch: do not complain about positive return values starting with EPOLL
  checkpatch: improve the indented label test
  checkpatch: scripts/spdxcheck.py now requires python3
  ...

kernel.h: split out panic and oops helpers

2021-07-01T18:06:04+00:00

kernel.h is being used as a dump for all kinds of stuff for a long time.
Here is the attempt to start cleaning it up by splitting out panic and
oops helpers.

There are several purposes of doing this:
- dropping dependency in bug.h
- dropping a loop by moving out panic_notifier.h
- unload kernel.h from something which has its own domain

At the same time convert users tree-wide to use new headers, although for
the time being include new header back to kernel.h to avoid twisted
indirected includes for existing users.

[akpm@linux-foundation.org: thread_info.h needs limits.h]
[andriy.shevchenko@linux.intel.com: ia64 fix]
  Link: https://lkml.kernel.org/r/20210520130557.55277-1-andriy.shevchenko@linux.intel.com

Link: https://lkml.kernel.org/r/20210511074137.33666-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko 
Reviewed-by: Bjorn Andersson 
Co-developed-by: Andrew Morton 
Acked-by: Mike Rapoport 
Acked-by: Corey Minyard 
Acked-by: Christian Brauner 
Acked-by: Arnd Bergmann 
Acked-by: Kees Cook 
Acked-by: Wei Liu 
Acked-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Acked-by: Sebastian Reichel 
Acked-by: Luis Chamberlain 
Acked-by: Stephen Boyd 
Acked-by: Thomas Bogendoerfer 
Acked-by: Helge Deller  # parisc
Signed-off-by: Linus Torvalds