Commit Graph

8852 Commits

Author SHA1 Message Date
Christophe Leroy
4eb6e78b3f powerpc: Only define __parse_fpscr() when required
[ Upstream commit c7e0d9bb91 ]

Clang 17 reports:

arch/powerpc/kernel/traps.c:1167:19: error: unused function '__parse_fpscr' [-Werror,-Wunused-function]

__parse_fpscr() is called from two sites. First call is guarded
by #ifdef CONFIG_PPC_FPU_REGS

Second call is guarded by CONFIG_MATH_EMULATION which selects
CONFIG_PPC_FPU_REGS.

So only define __parse_fpscr() when CONFIG_PPC_FPU_REGS is defined.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202309210327.WkqSd5Bq-lkp@intel.com/
Fixes: b6254ced4d ("powerpc/signal: Don't manage floating point regs when no FPU")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/5de2998c57f3983563b27b39228ea9a7229d4110.1695385984.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:57:15 +01:00
Michael Ellerman
fd318cc5b2 powerpc/mm: Fix boot crash with FLATMEM
[ Upstream commit daa9ada209 ]

Erhard reported that his G5 was crashing with v6.6-rc kernels:

  mpic: Setting up HT PICs workarounds for U3/U4
  BUG: Unable to handle kernel data access at 0xfeffbb62ffec65fe
  Faulting instruction address: 0xc00000000005dc40
  Oops: Kernel access of bad area, sig: 11 [#1]
  BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 PowerMac
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper/0 Tainted: G                T  6.6.0-rc3-PMacGS #1
  Hardware name: PowerMac11,2 PPC970MP 0x440101 PowerMac
  NIP:  c00000000005dc40 LR: c000000000066660 CTR: c000000000007730
  REGS: c0000000022bf510 TRAP: 0380   Tainted: G                T (6.6.0-rc3-PMacGS)
  MSR:  9000000000001032 <SF,HV,ME,IR,DR,RI>  CR: 44004242  XER: 00000000
  IRQMASK: 3
  GPR00: 0000000000000000 c0000000022bf7b0 c0000000010c0b00 00000000000001ac
  GPR04: 0000000003c80000 0000000000000300 c0000000f20001ae 0000000000000300
  GPR08: 0000000000000006 feffbb62ffec65ff 0000000000000001 0000000000000000
  GPR12: 9000000000001032 c000000002362000 c000000000f76b80 000000000349ecd8
  GPR16: 0000000002367ba8 0000000002367f08 0000000000000006 0000000000000000
  GPR20: 00000000000001ac c000000000f6f920 c0000000022cd985 000000000000000c
  GPR24: 0000000000000300 00000003b0a3691d c0003e008030000e 0000000000000000
  GPR28: c00000000000000c c0000000f20001ee feffbb62ffec65fe 00000000000001ac
  NIP hash_page_do_lazy_icache+0x50/0x100
  LR  __hash_page_4K+0x420/0x590
  Call Trace:
    hash_page_mm+0x364/0x6f0
    do_hash_fault+0x114/0x2b0
    data_access_common_virt+0x198/0x1f0
  --- interrupt: 300 at mpic_init+0x4bc/0x10c4
  NIP:  c000000002020a5c LR: c000000002020a04 CTR: 0000000000000000
  REGS: c0000000022bf9f0 TRAP: 0300   Tainted: G                T (6.6.0-rc3-PMacGS)
  MSR:  9000000000001032 <SF,HV,ME,IR,DR,RI>  CR: 24004248  XER: 00000000
  DAR: c0003e008030000e DSISR: 40000000 IRQMASK: 1
  ...
  NIP mpic_init+0x4bc/0x10c4
  LR  mpic_init+0x464/0x10c4
  --- interrupt: 300
    pmac_setup_one_mpic+0x258/0x2dc
    pmac_pic_init+0x28c/0x3d8
    init_IRQ+0x90/0x140
    start_kernel+0x57c/0x78c
    start_here_common+0x1c/0x20

A bisect pointed to the breakage beginning with commit 9fee28baa6 ("powerpc:
implement the new page table range API").

Analysis of the oops pointed to a struct page with a corrupted
compound_head being loaded via page_folio() -> _compound_head() in
hash_page_do_lazy_icache().

The access by the mpic code is to an MMIO address, so the expectation
is that the struct page for that address would be initialised by
init_unavailable_range(), as pointed out by Aneesh.

Instrumentation showed that was not the case, which eventually lead to
the realisation that pfn_valid() was returning false for that address,
causing the struct page to not be initialised.

Because the system is using FLATMEM, the version of pfn_valid() in
memory_model.h is used:

static inline int pfn_valid(unsigned long pfn)
{
	...
	return pfn >= pfn_offset && (pfn - pfn_offset) < max_mapnr;
}

Which relies on max_mapnr being initialised. Early in boot max_mapnr is
zero meaning no PFNs are valid.

max_mapnr is initialised in mem_init() called via:

  start_kernel()
    mm_core_init()  # init/main.c:928
      mem_init()

But that is too late for the usage in init_unavailable_range() called via:

  start_kernel()
    setup_arch()    # init/main.c:893
      paging_init()
        free_area_init()
          init_unavailable_range()

Although max_mapnr is currently set in mem_init(), the value is actually
already available much earlier, as soon as mem_topology_setup() has
completed, which is also before paging_init() is called. So move the
initialisation there, which causes paging_init() to correctly initialise
the struct page and fixes the bug.

This bug seems to have been lurking for years, but went unnoticed
because the pre-folio code was inspecting the uninitialised page->flags
but not dereferencing it.

Thanks to Erhard and Aneesh for help debugging.

Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Closes: https://lore.kernel.org/all/20230929132750.3cd98452@yea/
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231023112500.1550208-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-08 14:09:03 +01:00
Christophe Leroy
d4c3cb925e powerpc/85xx: Fix math emulation exception
[ Upstream commit 8e8a12ecbc ]

Booting mpc85xx_defconfig kernel on QEMU leads to:

Bad trap at PC: fe9bab0, SR: 2d000, vector=800
awk[82]: unhandled trap (5) at 0 nip fe9bab0 lr fe9e01c code 5 in libc-2.27.so[fe5a000+17a000]
awk[82]: code: 3aa00000 3a800010 4bffe03c 9421fff0 7ca62b78 38a00000 93c10008 83c10008
awk[82]: code: 38210010 4bffdec8 9421ffc0 7c0802a6 <fc00048e> d8010008 4815190d 93810030
Trace/breakpoint trap
WARNING: no useful console

This is because allthough CONFIG_MATH_EMULATION is selected,
Exception 800 calls unknown_exception().

Call emulation_assist_interrupt() instead.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/066caa6d9480365da9b8ed83692d7101e10ac5f8.1695657339.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-08 14:08:57 +01:00
Michael Ellerman
70f6756ad9 powerpc/47x: Fix 47x syscall return crash
commit f0eee815ba upstream.

Eddie reported that newer kernels were crashing during boot on his 476
FSP2 system:

  kernel tried to execute user page (b7ee2000) - exploit attempt? (uid: 0)
  BUG: Unable to handle kernel instruction fetch
  Faulting instruction address: 0xb7ee2000
  Oops: Kernel access of bad area, sig: 11 [#1]
  BE PAGE_SIZE=4K FSP-2
  Modules linked in:
  CPU: 0 PID: 61 Comm: mount Not tainted 6.1.55-d23900f.ppcnf-fsp2 #1
  Hardware name: ibm,fsp2 476fpe 0x7ff520c0 FSP-2
  NIP:  b7ee2000 LR: 8c008000 CTR: 00000000
  REGS: bffebd83 TRAP: 0400   Not tainted (6.1.55-d23900f.ppcnf-fs p2)
  MSR:  00000030 <IR,DR>  CR: 00001000  XER: 20000000
  GPR00: c00110ac bffebe63 bffebe7e bffebe88 8c008000 00001000 00000d12 b7ee2000
  GPR08: 00000033 00000000 00000000 c139df10 48224824 1016c314 10160000 00000000
  GPR16: 10160000 10160000 00000008 00000000 10160000 00000000 10160000 1017f5b0
  GPR24: 1017fa50 1017f4f0 1017fa50 1017f740 1017f630 00000000 00000000 1017f4f0
  NIP [b7ee2000] 0xb7ee2000
  LR [8c008000] 0x8c008000
  Call Trace:
  Instruction dump:
  XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
  XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
  ---[ end trace 0000000000000000 ]---

The problem is in ret_from_syscall where the check for
icache_44x_need_flush is done. When the flush is needed the code jumps
out-of-line to do the flush, and then intends to jump back to continue
the syscall return.

However the branch back to label 1b doesn't return to the correct
location, instead branching back just prior to the return to userspace,
causing bogus register values to be used by the rfi.

The breakage was introduced by commit 6f76a01173
("powerpc/syscall: implement system call entry/exit logic in C for PPC32") which
inadvertently removed the "1" label and reused it elsewhere.

Fix it by adding named local labels in the correct locations. Note that
the return label needs to be outside the ifdef so that CONFIG_PPC_47x=n
compiles.

Fixes: 6f76a01173 ("powerpc/syscall: implement system call entry/exit logic in C for PPC32")
Cc: stable@vger.kernel.org # v5.12+
Reported-by: Eddie James <eajames@linux.ibm.com>
Tested-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/linuxppc-dev/fdaadc46-7476-9237-e104-1d2168526e72@linux.ibm.com/
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://msgid.link/20231010114750.847794-1-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-19 23:11:05 +02:00
Benjamin Gray
c91f3228fa powerpc/watchpoints: Annotate atomic context in more places
[ Upstream commit 27646b2e02 ]

It can be easy to miss that the notifier mechanism invokes the callbacks
in an atomic context, so add some comments to that effect on the two
handlers we register here.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230829063457.54157-4-bgray@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06 13:16:17 +02:00
Benjamin Gray
3799888a6b powerpc/watchpoint: Disable pagefaults when getting user instruction
[ Upstream commit 3241f260eb ]

This is called in an atomic context, so is not allowed to sleep if a
user page needs to be faulted in and has nowhere it can be deferred to.
The pagefault_disabled() function is documented as preventing user
access methods from sleeping.

In practice the page will be mapped in nearly always because we are
reading the instruction that just triggered the watchpoint trap.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230829063457.54157-3-bgray@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06 13:16:16 +02:00
Benjamin Gray
98ac791d40 powerpc/watchpoints: Disable preemption in thread_change_pc()
[ Upstream commit cc879ab3ce ]

thread_change_pc() uses CPU local data, so must be protected from
swapping CPUs while it is reading the breakpoint struct.

The error is more noticeable after 1e60f3564b ("powerpc/watchpoints:
Track perf single step directly on the breakpoint"), which added an
unconditional __this_cpu_read() call in thread_change_pc(). However the
existing __this_cpu_read() that runs if a breakpoint does need to be
re-inserted has the same issue.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230829063457.54157-2-bgray@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06 13:16:16 +02:00
Michael Ellerman
59d6419750 powerpc/stacktrace: Fix arch_stack_walk_reliable()
[ Upstream commit c5cc3ca707 ]

The changes to copy_thread() made in commit eed7c420aa ("powerpc:
copy_thread differentiate kthreads and user mode threads") inadvertently
broke arch_stack_walk_reliable() because it has knowledge of the stack
layout.

Fix it by changing the condition to match the new logic in
copy_thread(). The changes make the comments about the stack layout
incorrect, rather than rephrasing them just refer the reader to
copy_thread().

Also the comment about the stack backchain is no longer true, since
commit edbd0387f3 ("powerpc: copy_thread add a back chain to the
switch stack frame"), so remove that as well.

Fixes: eed7c420aa ("powerpc: copy_thread differentiate kthreads and user mode threads")
Reported-by: Joe Lawrence <joe.lawrence@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230921232441.1181843-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06 13:16:05 +02:00
Benjamin Gray
82c302f3eb powerpc/dexcr: Move HASHCHK trap handler
[ Upstream commit c3f4309693 ]

Syzkaller reported a sleep in atomic context bug relating to the HASHCHK
handler logic:

  BUG: sleeping function called from invalid context at arch/powerpc/kernel/traps.c:1518
  in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 25040, name: syz-executor
  preempt_count: 0, expected: 0
  RCU nest depth: 0, expected: 0
  no locks held by syz-executor/25040.
  irq event stamp: 34
  hardirqs last  enabled at (33): [<c000000000048b38>] prep_irq_for_enabled_exit arch/powerpc/kernel/interrupt.c:56 [inline]
  hardirqs last  enabled at (33): [<c000000000048b38>] interrupt_exit_user_prepare_main+0x148/0x600 arch/powerpc/kernel/interrupt.c:230
  hardirqs last disabled at (34): [<c00000000003e6a4>] interrupt_enter_prepare+0x144/0x4f0 arch/powerpc/include/asm/interrupt.h:176
  softirqs last  enabled at (0): [<c000000000281954>] copy_process+0x16e4/0x4750 kernel/fork.c:2436
  softirqs last disabled at (0): [<0000000000000000>] 0x0
  CPU: 15 PID: 25040 Comm: syz-executor Not tainted 6.5.0-rc5-00001-g3ccdff6bb06d #3
  Hardware name: IBM,9105-22A POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1040.00 (NL1040_021) hv:phyp pSeries
  Call Trace:
  [c0000000a8247ce0] [c00000000032b0e4] __might_resched+0x3b4/0x400 kernel/sched/core.c:10189
  [c0000000a8247d80] [c0000000008c7dc8] __might_fault+0xa8/0x170 mm/memory.c:5853
  [c0000000a8247dc0] [c00000000004160c] do_program_check+0x32c/0xb20 arch/powerpc/kernel/traps.c:1518
  [c0000000a8247e50] [c000000000009b2c] program_check_common_virt+0x3bc/0x3c0

To determine if a trap was caused by a HASHCHK instruction, we inspect
the user instruction that triggered the trap. However this may sleep
if the page needs to be faulted in (get_user_instr() reaches
__get_user(), which calls might_fault() and triggers the bug message).

Move the HASHCHK handler logic to after we allow IRQs, which is fine
because we are only interested in HASHCHK if it's a user space trap.

Fixes: 5bcba4e6c1 ("powerpc/dexcr: Handle hashchk exception")
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230915034604.45393-1-bgray@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06 13:15:53 +02:00
Russell Currey
6670c65bf8 powerpc/iommu: Fix notifiers being shared by PCI and VIO buses
[ Upstream commit c37b6908f7 ]

fail_iommu_setup() registers the fail_iommu_bus_notifier struct to both
PCI and VIO buses.  struct notifier_block is a linked list node, so this
causes any notifiers later registered to either bus type to also be
registered to the other since they share the same node.

This causes issues in (at least) the vgaarb code, which registers a
notifier for PCI buses.  pci_notify() ends up being called on a vio
device, converted with to_pci_dev() even though it's not a PCI device,
and finally makes a bad access in vga_arbiter_add_pci_device() as
discovered with KASAN:

 BUG: KASAN: slab-out-of-bounds in vga_arbiter_add_pci_device+0x60/0xe00
 Read of size 4 at addr c000000264c26fdc by task swapper/0/1

 Call Trace:
   dump_stack_lvl+0x1bc/0x2b8 (unreliable)
   print_report+0x3f4/0xc60
   kasan_report+0x244/0x698
   __asan_load4+0xe8/0x250
   vga_arbiter_add_pci_device+0x60/0xe00
   pci_notify+0x88/0x444
   notifier_call_chain+0x104/0x320
   blocking_notifier_call_chain+0xa0/0x140
   device_add+0xac8/0x1d30
   device_register+0x58/0x80
   vio_register_device_node+0x9ac/0xce0
   vio_bus_scan_register_devices+0xc4/0x13c
   __machine_initcall_pseries_vio_device_init+0x94/0xf0
   do_one_initcall+0x12c/0xaa8
   kernel_init_freeable+0xa48/0xba8
   kernel_init+0x64/0x400
   ret_from_kernel_thread+0x5c/0x64

Fix this by creating separate notifier_block structs for each bus type.

Fixes: d6b9a81b2a ("powerpc: IOMMU fault injection")
Reported-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Tested-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
[mpe: Add #ifdef to fix CONFIG_IBMVIO=n build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230322035322.328709-1-ruscur@russell.cc
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13 09:53:33 +02:00
Sourabh Jain
7cad534400 powerpc/fadump: reset dump area size if fadump memory reserve fails
[ Upstream commit d1eb75e0df ]

In case fadump_reserve_mem() fails to reserve memory, the
reserve_dump_area_size variable will retain the reserve area size. This
will lead to /sys/kernel/fadump/mem_reserved node displaying an incorrect
memory reserved by fadump.

To fix this problem, reserve dump area size variable is set to 0 if fadump
failed to reserve memory.

Fixes: 8255da95e5 ("powerpc/fadump: release all the memory above boot memory size")
Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Acked-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230704050715.203581-1-sourabhjain@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13 09:53:31 +02:00
Douglas Anderson
4d880fc4a2 nmi_backtrace: allow excluding an arbitrary CPU
[ Upstream commit 8d539b84f1 ]

The APIs that allow backtracing across CPUs have always had a way to
exclude the current CPU.  This convenience means callers didn't need to
find a place to allocate a CPU mask just to handle the common case.

Let's extend the API to take a CPU ID to exclude instead of just a
boolean.  This isn't any more complex for the API to handle and allows the
hardlockup detector to exclude a different CPU (the one it already did a
trace for) without needing to find space for a CPU mask.

Arguably, this new API also encourages safer behavior.  Specifically if
the caller wants to avoid tracing the current CPU (maybe because they
already traced the current CPU) this makes it more obvious to the caller
that they need to make sure that the current CPU ID can't change.

[akpm@linux-foundation.org: fix trigger_allbutcpu_cpu_backtrace() stub]
Link: https://lkml.kernel.org/r/20230804065935.v4.1.Ia35521b91fc781368945161d7b28538f9996c182@changeid
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stable-dep-of: 1f38c86bb2 ("watchdog/hardlockup: avoid large stack frames in watchdog_hardlockup_check()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13 09:53:08 +02:00
Nathan Lynch
4f3175979e powerpc/rtas_flash: allow user copy to flash block cache objects
With hardened usercopy enabled (CONFIG_HARDENED_USERCOPY=y), using the
/proc/powerpc/rtas/firmware_update interface to prepare a system
firmware update yields a BUG():

  kernel BUG at mm/usercopy.c:102!
  Oops: Exception in kernel mode, sig: 5 [#1]
  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
  Modules linked in:
  CPU: 0 PID: 2232 Comm: dd Not tainted 6.5.0-rc3+ #2
  Hardware name: IBM,8408-E8E POWER8E (raw) 0x4b0201 0xf000004 of:IBM,FW860.50 (SV860_146) hv:phyp pSeries
  NIP:  c0000000005991d0 LR: c0000000005991cc CTR: 0000000000000000
  REGS: c0000000148c76a0 TRAP: 0700   Not tainted  (6.5.0-rc3+)
  MSR:  8000000000029033 <SF,EE,ME,IR,DR,RI,LE>  CR: 24002242  XER: 0000000c
  CFAR: c0000000001fbd34 IRQMASK: 0
  [ ... GPRs omitted ... ]
  NIP usercopy_abort+0xa0/0xb0
  LR  usercopy_abort+0x9c/0xb0
  Call Trace:
    usercopy_abort+0x9c/0xb0 (unreliable)
    __check_heap_object+0x1b4/0x1d0
    __check_object_size+0x2d0/0x380
    rtas_flash_write+0xe4/0x250
    proc_reg_write+0xfc/0x160
    vfs_write+0xfc/0x4e0
    ksys_write+0x90/0x160
    system_call_exception+0x178/0x320
    system_call_common+0x160/0x2c4

The blocks of the firmware image are copied directly from user memory
to objects allocated from flash_block_cache, so flash_block_cache must
be created using kmem_cache_create_usercopy() to mark it safe for user
access.

Fixes: 6d07d1cd30 ("usercopy: Restrict non-usercopy caches to size 0")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
[mpe: Trim and indent oops]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230810-rtas-flash-vs-hardened-usercopy-v2-1-dcf63793a938@linux.ibm.com
2023-08-17 09:46:14 +10:00
Michael Ellerman
2dc0bc1138 powerpc/64e: Fix secondary thread bringup for ELFv2 kernels
When booting on e6500 with an ELF v2 ABI kernel, the secondary threads do
not start correctly:

    [    0.051118] smp: Bringing up secondary CPUs ...
    [    5.072700] Processor 1 is stuck.

This occurs because the startup code is written to use function
descriptors when loading the entry point for the secondary threads. When
building with ELF v2 ABI there are no function descriptors, and the code
loads junk values for the entry point address.

Fix it by using ppc_function_entry() in C, and DOTSYM() in asm, both of
which work correctly for ELF v2 ABI as well as ELF v1 ABI kernels.

Fixes: 8c5fa3b5c4 ("powerpc/64: Make ELFv2 the default for big-endian builds")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230801102650.48705-1-mpe@ellerman.id.au
2023-08-01 21:01:27 +10:00
Naveen N Rao
41a506ef71 powerpc/ftrace: Create a dummy stackframe to fix stack unwind
With ppc64 -mprofile-kernel and ppc32 -pg, profiling instructions to
call into ftrace are emitted right at function entry. The instruction
sequence used is minimal to reduce overhead. Crucially, a stackframe is
not created for the function being traced. This breaks stack unwinding
since the function being traced does not have a stackframe for itself.
As such, it never shows up in the backtrace:

/sys/kernel/debug/tracing # echo 1 > /proc/sys/kernel/stack_tracer_enabled
/sys/kernel/debug/tracing # cat stack_trace
        Depth    Size   Location    (17 entries)
        -----    ----   --------
  0)     4144      32   ftrace_call+0x4/0x44
  1)     4112     432   get_page_from_freelist+0x26c/0x1ad0
  2)     3680     496   __alloc_pages+0x290/0x1280
  3)     3184     336   __folio_alloc+0x34/0x90
  4)     2848     176   vma_alloc_folio+0xd8/0x540
  5)     2672     272   __handle_mm_fault+0x700/0x1cc0
  6)     2400     208   handle_mm_fault+0xf0/0x3f0
  7)     2192      80   ___do_page_fault+0x3e4/0xbe0
  8)     2112     160   do_page_fault+0x30/0xc0
  9)     1952     256   data_access_common_virt+0x210/0x220
 10)     1696     400   0xc00000000f16b100
 11)     1296     384   load_elf_binary+0x804/0x1b80
 12)      912     208   bprm_execve+0x2d8/0x7e0
 13)      704      64   do_execveat_common+0x1d0/0x2f0
 14)      640     160   sys_execve+0x54/0x70
 15)      480      64   system_call_exception+0x138/0x350
 16)      416     416   system_call_common+0x160/0x2c4

Fix this by having ftrace create a dummy stackframe for the function
being traced. With this, backtraces now capture the function being
traced:

/sys/kernel/debug/tracing # cat stack_trace
        Depth    Size   Location    (17 entries)
        -----    ----   --------
  0)     3888      32   _raw_spin_trylock+0x8/0x70
  1)     3856     576   get_page_from_freelist+0x26c/0x1ad0
  2)     3280      64   __alloc_pages+0x290/0x1280
  3)     3216     336   __folio_alloc+0x34/0x90
  4)     2880     176   vma_alloc_folio+0xd8/0x540
  5)     2704     416   __handle_mm_fault+0x700/0x1cc0
  6)     2288      96   handle_mm_fault+0xf0/0x3f0
  7)     2192      48   ___do_page_fault+0x3e4/0xbe0
  8)     2144     192   do_page_fault+0x30/0xc0
  9)     1952     608   data_access_common_virt+0x210/0x220
 10)     1344      16   0xc0000000334bbb50
 11)     1328     416   load_elf_binary+0x804/0x1b80
 12)      912      64   bprm_execve+0x2d8/0x7e0
 13)      848     176   do_execveat_common+0x1d0/0x2f0
 14)      672     192   sys_execve+0x54/0x70
 15)      480      64   system_call_exception+0x138/0x350
 16)      416     416   system_call_common+0x160/0x2c4

This results in two additional stores in the ftrace entry code, but
produces reliable backtraces.

Fixes: 153086644f ("powerpc/ftrace: Add support for -mprofile-kernel ftrace ABI")
Cc: stable@vger.kernel.org
Signed-off-by: Naveen N Rao <naveen@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230621051349.759567-1-naveen@kernel.org
2023-07-28 20:23:57 +10:00
Christophe Leroy
b49e578b93 Revert "powerpc/bug: Provide better flexibility to WARN_ON/__WARN_FLAGS() with asm goto"
This partly reverts commit 1e688dd2a3.

That commit aimed at optimising the code around generation of
WARN_ON/BUG_ON but this leads to a lot of dead code erroneously
generated by GCC.

That dead code becomes a problem when we start using objtool validation
because objtool will abort validation with a warning as soon as it
detects unreachable code. This is because unreachable code might
be the indication that objtool doesn't properly decode object text.

     text	   data	    bss	    dec	    hex	filename
  9551585	3627834	 224376	13403795	 cc8693	vmlinux.before
  9535281	3628358	 224376	13388015	 cc48ef	vmlinux.after

Once this change is reverted, in a standard configuration (pmac32 +
function tracer) the text is reduced by 16k which is around 1.7%

We already had problem with it when starting to use objtool on powerpc
as a replacement for recordmcount, see commit 93e3f45a26 ("powerpc:
Fix __WARN_FLAGS() for use with Objtool")

There is also a problem with at least GCC 12, on ppc64_defconfig +
CONFIG_CC_OPTIMIZE_FOR_SIZE=y + CONFIG_DEBUG_SECTION_MISMATCH=y :

    LD      .tmp_vmlinux.kallsyms1
  powerpc64-linux-ld: net/ipv4/tcp_input.o:(__ex_table+0xc4): undefined reference to `.L2136'
  make[2]: *** [scripts/Makefile.vmlinux:36: vmlinux] Error 1
  make[1]: *** [/home/chleroy/linux-powerpc/Makefile:1238: vmlinux] Error 2

Taking into account that other problems are encountered with that
'asm goto' in WARN_ON(), including build failures, keeping that
change is not worth it allthough it is primarily a compiler bug.

Revert it for now.

mpe: Retain EMIT_WARN_ENTRY as a synonym for EMIT_BUG_ENTRY to reduce
churn, as there are now nearly as many uses of EMIT_WARN_ENTRY as
EMIT_BUG_ENTRY.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Naveen N Rao <naveen@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230712134552.534955-1-mpe@ellerman.id.au
2023-07-17 10:35:28 +10:00
Michael Ellerman
cf65b12c17 powerpc/64e: Fix obtool warnings in exceptions-64e.S
Since commit aec0ba7472 ("powerpc/64: Use -mprofile-kernel for big
endian ELFv2 kernels"), this file is checked by objtool. Fix warnings
such as:

  arch/powerpc/kernel/idle_64e.o: warning: objtool: .text+0x20: unannotated intra-function call
  arch/powerpc/kernel/exceptions-64e.o: warning: objtool: .text+0x218: unannotated intra-function call

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230622112451.735268-1-mpe@ellerman.id.au
2023-07-10 09:47:47 +10:00
Michael Ellerman
5bcedc5931 powerpc/security: Fix Speculation_Store_Bypass reporting on Power10
Nageswara reported that /proc/self/status was showing "vulnerable" for
the Speculation_Store_Bypass feature on Power10, eg:

  $ grep Speculation_Store_Bypass: /proc/self/status
  Speculation_Store_Bypass:       vulnerable

But at the same time the sysfs files, and lscpu, were showing "Not
affected".

This turns out to simply be a bug in the reporting of the
Speculation_Store_Bypass, aka. PR_SPEC_STORE_BYPASS, case.

When SEC_FTR_STF_BARRIER was added, so that firmware could communicate
the vulnerability was not present, the code in ssb_prctl_get() was not
updated to check the new flag.

So add the check for SEC_FTR_STF_BARRIER being disabled. Rather than
adding the new check to the existing if block and expanding the comment
to cover both cases, rewrite the three cases to be separate so they can
be commented separately for clarity.

Fixes: 84ed26fd00 ("powerpc/security: Add a security feature for STF barrier")
Cc: stable@vger.kernel.org # v5.14+
Reported-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Tested-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Reviewed-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230517074945.53188-1-mpe@ellerman.id.au
2023-07-10 09:47:47 +10:00
Linus Torvalds
868a9fd948 Merge tag 'tty-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
 "Here is the big set of tty/serial driver updates for 6.5-rc1.

  Included in here are:

   - tty_audit code cleanups from Jiri

   - more 8250 cleanups from Ilpo

   - samsung_tty driver bugfixes

   - 8250 lock port updates

   - usual fsl_lpuart driver updates and fixes

   - other small serial driver fixes and updates, full details in the
     shortlog

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (58 commits)
  tty_audit: make data of tty_audit_log() const
  tty_audit: make tty pointers in exposed functions const
  tty_audit: make icanon a bool
  tty_audit: invert the condition in tty_audit_log()
  tty_audit: use kzalloc() in tty_audit_buf_alloc()
  tty_audit: use TASK_COMM_LEN for task comm
  Revert "8250: add support for ASIX devices with a FIFO bug"
  serial: atmel: don't enable IRQs prematurely
  tty: serial: Add Nuvoton ma35d1 serial driver support
  tty: serial: fsl_lpuart: add earlycon for imx8ulp platform
  tty: serial: imx: fix rs485 rx after tx
  selftests: tty: add selftest for tty timestamp updates
  tty: tty_io: update timestamps on all device nodes
  tty: fix hang on tty device with no_room set
  serial: core: fix -EPROBE_DEFER handling in init
  serial: 8250_omap: Use force_suspend and resume for system suspend
  tty: serial: samsung_tty: Use abs() to simplify some code
  tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() when iterating clk
  tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() in case of error
  serial: 8250: Apply FSL workarounds also without SERIAL_8250_CONSOLE
  ...
2023-07-03 13:14:58 -07:00
Linus Torvalds
ad2885979e Merge tag 'kbuild-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:

 - Remove the deprecated rule to build *.dtbo from *.dts

 - Refactor section mismatch detection in modpost

 - Fix bogus ARM section mismatch detections

 - Fix error of 'make gtags' with O= option

 - Add Clang's target triple to KBUILD_CPPFLAGS to fix a build error
   with the latest LLVM version

 - Rebuild the built-in initrd when KBUILD_BUILD_TIMESTAMP is changed

 - Ignore more compiler-generated symbols for kallsyms

 - Fix 'make local*config' to handle the ${CONFIG_FOO} form in Makefiles

 - Enable more kernel-doc warnings with W=2

 - Refactor <linux/export.h> by generating KSYMTAB data by modpost

 - Deprecate <asm/export.h> and <asm-generic/export.h>

 - Remove the EXPORT_DATA_SYMBOL macro

 - Move the check for static EXPORT_SYMBOL back to modpost, which makes
   the build faster

 - Re-implement CONFIG_TRIM_UNUSED_KSYMS with one-pass algorithm

 - Warn missing MODULE_DESCRIPTION when building modules with W=1

 - Make 'make clean' robust against too long argument error

 - Exclude more objects from GCOV to fix CFI failures with GCOV

 - Allow 'make modules_install' to install modules.builtin and
   modules.builtin.modinfo even when CONFIG_MODULES is disabled

 - Include modules.builtin and modules.builtin.modinfo in the
   linux-image Debian package even when CONFIG_MODULES is disabled

 - Revive "Entering directory" logging for the latest Make version

* tag 'kbuild-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (72 commits)
  modpost: define more R_ARM_* for old distributions
  kbuild: revive "Entering directory" for Make >= 4.4.1
  kbuild: set correct abs_srctree and abs_objtree for package builds
  scripts/mksysmap: Ignore prefixed KCFI symbols
  kbuild: deb-pkg: remove the CONFIG_MODULES check in buildeb
  kbuild: builddeb: always make modules_install, to install modules.builtin*
  modpost: continue even with unknown relocation type
  modpost: factor out Elf_Sym pointer calculation to section_rel()
  modpost: factor out inst location calculation to section_rel()
  kbuild: Disable GCOV for *.mod.o
  kbuild: Fix CFI failures with GCOV
  kbuild: make clean rule robust against too long argument error
  script: modpost: emit a warning when the description is missing
  kbuild: make modules_install copy modules.builtin(.modinfo)
  linux/export.h: rename 'sec' argument to 'license'
  modpost: show offset from symbol for section mismatch warnings
  modpost: merge two similar section mismatch warnings
  kbuild: implement CONFIG_TRIM_UNUSED_KSYMS without recursion
  modpost: use null string instead of NULL pointer for default namespace
  modpost: squash sym_update_namespace() into sym_add_exported()
  ...
2023-07-01 09:24:31 -07:00
Linus Torvalds
9070577ae9 Merge tag 'pci-v6.5-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
Pull pci updates from Bjorn Helgaas:
 "Enumeration:

   - Export pcie_retrain_link() for use outside ASPM

   - Add Data Link Layer Link Active Reporting as another way for
     pcie_retrain_link() to determine the link is up

   - Work around link training failures (especially on the ASMedia
     ASM2824 switch) by training first at 2.5GT/s and then attempting
     higher rates

  Resource management:

   - When we coalesce host bridge windows, remove invalidated resources
     from the resource tree so future allocations work correctly

  Hotplug:

   - Cancel bringup sequence if card is not present, to keep from
     blinking Power Indicator indefinitely

   - Reassign bridge resources if necessary for ACPI hotplug

  Driver binding:

   - Convert platform_device .remove() callbacks to return void instead
     of a mostly useless int

  Power management:

   - Reduce wait time for secondary bus to be ready to speed up resume

   - Avoid putting EloPOS E2/S2/H2 (as well as Elo i2) PCIe Ports in
     D3cold

   - Call _REG when transitioning D-states so AML that uses the PCI
     config space OpRegion works, which fixes some ASMedia GPIO
     controllers after resume

  Virtualization:

   - Delay extra 250ms after FLR of Solidigm P44 Pro NVMe to avoid KVM
     hang when guest is rebooted

   - Add function 1 DMA alias quirk for Marvell 88SE9235

  Error handling:

   - Unexport pci_save_aer_state() since it's only used in drivers/pci/

   - Drop recommendation for drivers to configure AER Capability, since
     the PCI core does this for all devices

  ASPM:

   - Disable ASPM on MFD function removal to avoid use-after-free

   - Tighten up pci_enable_link_state() and pci_disable_link_state()
     interfaces so they don't enable/disable states the driver didn't
     specify

   - Avoid link retraining race that can happen if ASPM sets link
     control parameters while the link is in the midst of training for
     some other reason

  Endpoint framework:

   - Change "PCI Endpoint Virtual NTB driver" Kconfig prompt to be
     different from "PCI Endpoint NTB driver"

   - Automatically create a function specific attributes group for
     endpoint drivers to avoid reference counting issues

   - Fix many EPC test issues

   - Return pci_epf_type_add_cfs() error if EPF has no driver

   - Add kernel-doc for pci_epc_raise_irq() and pci_epc_map_msi_irq()
     MSI vector parameters

   - Pass EPF device ID to driver probe functions

   - Return -EALREADY if EPC has already been started/stopped

   - Add linkdown notifier support and use it in qcom-ep

   - Add Bus Master Enable event support and use it in qcom-ep

   - Add Qualcomm Modem Host Interface (MHI) endpoint driver

   - Add Layerscape PME interrupt handling to manage link-up
     notification

  Cadence PCIe controller driver:

   - Wait for link retrain to complete when working around the J721E
     i2085 erratum with Gen2 mode

  Faraday FTPC100 PCI controller driver:

   - Release clock resources on error paths

  Freescale i.MX6 PCIe controller driver:

   - Save and restore Root Port MSI control to work around hardware defect

  Intel VMD host bridge driver:

   - Reset VMD config register between soft reboots

   - Capture pci_reset_bus() return value instead of printing junk when
     it fails

  Qualcomm PCIe controller driver:

   - Add SDX65 endpoint compatible string to DT binding

   - Disable register write access after init for IP v2.3.3, v2.9.0

   - Use DWC helpers for enabling/disabling writes to DBI registers

   - Hide slot hotplug capability for IP v1.0.0, v1.9.0, v2.1.0, v2.3.2,
     v2.3.3, v2.7.0, v2.9.0

   - Reuse v2.3.2 post-init sequence for v2.4.0

  Renesas R-Car PCIe controller driver:

   - Remove unused static pcie_base and pcie_dev

  Rockchip PCIe controller driver:

   - Remove writes to unused registers

   - Write endpoint Device ID using correct register

   - Assert PCI Configuration Enable bit after probe so endpoint
     responds instead of generating Request Retry Status messages

   - Poll waiting for PHY PLLs to lock

   - Update RK3399 example DT binding to be valid

   - Use RK3399 PCIE_CLIENT_LEGACY_INT_CTRL to generate INTx instead of
     manually generating PCIe message

   - Use multiple windows to avoid address translation conflicts

   - Use u32 (not u16) when accessing 32-bit registers

   - Hide MSI-X Capability, since RK3399 can't generate MSI-X

   - Set endpoint controller required alignment to 256

  Synopsys DesignWare PCIe controller driver:

   - Wait for link to come up only if we've initiated link training

  Miscellaneous:

   - Add pci_clear_master() stub for non-CONFIG_PCI"

* tag 'pci-v6.5-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (116 commits)
  Documentation: PCI: correct spelling
  PCI: vmd: Fix uninitialized variable usage in vmd_enable_domain()
  PCI: xgene-msi: Convert to platform remove callback returning void
  PCI: tegra: Convert to platform remove callback returning void
  PCI: rockchip-host: Convert to platform remove callback returning void
  PCI: mvebu: Convert to platform remove callback returning void
  PCI: mt7621: Convert to platform remove callback returning void
  PCI: mediatek-gen3: Convert to platform remove callback returning void
  PCI: mediatek: Convert to platform remove callback returning void
  PCI: iproc: Convert to platform remove callback returning void
  PCI: hisi-error: Convert to platform remove callback returning void
  PCI: dwc: Convert to platform remove callback returning void
  PCI: j721e: Convert to platform remove callback returning void
  PCI: brcmstb: Convert to platform remove callback returning void
  PCI: altera-msi: Convert to platform remove callback returning void
  PCI: altera: Convert to platform remove callback returning void
  PCI: aardvark: Convert to platform remove callback returning void
  PCI: rcar: Use correct product family name for Renesas R-Car
  PCI: layerscape: Add the endpoint linkup notifier support
  PCI: endpoint: pci-epf-vntb: Fix typo in comments
  ...
2023-06-30 15:06:45 -07:00
Linus Torvalds
d8b0bd57c2 Merge tag 'powerpc-6.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:

 - Extend KCSAN support to 32-bit and BookE. Add some KCSAN annotations

 - Make ELFv2 ABI the default for 64-bit big-endian kernel builds, and
   use the -mprofile-kernel option (kernel specific ftrace ABI) for big
   endian ELFv2 kernels

 - Add initial Dynamic Execution Control Register (DEXCR) support, and
   allow the ROP protection instructions to be used on Power 10

 - Various other small features and fixes

Thanks to Aditya Gupta, Aneesh Kumar K.V, Benjamin Gray, Brian King,
Christophe Leroy, Colin Ian King, Dmitry Torokhov, Gaurav Batra, Jean
Delvare, Joel Stanley, Marco Elver, Masahiro Yamada, Nageswara R Sastry,
Nathan Chancellor, Naveen N Rao, Nayna Jain, Nicholas Piggin, Paul
Gortmaker, Randy Dunlap, Rob Herring, Rohan McLure, Russell Currey,
Sachin Sant, Timothy Pearson, Tom Rix, and Uwe Kleine-König.

* tag 'powerpc-6.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (76 commits)
  powerpc: remove checks for binutils older than 2.25
  powerpc: Fail build if using recordmcount with binutils v2.37
  powerpc/iommu: TCEs are incorrectly manipulated with DLPAR add/remove of memory
  powerpc/iommu: Only build sPAPR access functions on pSeries
  powerpc: powernv: Annotate data races in opal events
  powerpc: Mark writes registering ipi to host cpu through kvm and polling
  powerpc: Annotate accesses to ipi message flags
  powerpc: powernv: Fix KCSAN datarace warnings on idle_state contention
  powerpc: Mark [h]ssr_valid accesses in check_return_regs_valid
  powerpc: qspinlock: Enforce qnode writes prior to publishing to queue
  powerpc: qspinlock: Mark accesses to qnode lock checks
  powerpc/powernv/pci: Remove last IODA1 defines
  powerpc/powernv/pci: Remove MVE code
  powerpc/powernv/pci: Remove ioda1 support
  powerpc: 52xx: Make immr_id DT match tables static
  powerpc: mpc512x: Remove open coded "ranges" parsing
  powerpc: fsl_soc: Use of_range_to_resource() for "ranges" parsing
  powerpc: fsl: Use of_property_read_reg() to parse "reg"
  powerpc: fsl_rio: Use of_range_to_resource() for "ranges" parsing
  macintosh: Use of_property_read_reg() to parse "reg"
  ...
2023-06-30 09:20:08 -07:00
Linus Torvalds
77b1a7f7a0 Merge tag 'mm-nonmm-stable-2023-06-24-19-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-mm updates from Andrew Morton:

 - Arnd Bergmann has fixed a bunch of -Wmissing-prototypes in top-level
   directories

 - Douglas Anderson has added a new "buddy" mode to the hardlockup
   detector. It permits the detector to work on architectures which
   cannot provide the required interrupts, by having CPUs periodically
   perform checks on other CPUs

 - Zhen Lei has enhanced kexec's ability to support two crash regions

 - Petr Mladek has done a lot of cleanup on the hard lockup detector's
   Kconfig entries

 - And the usual bunch of singleton patches in various places

* tag 'mm-nonmm-stable-2023-06-24-19-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits)
  kernel/time/posix-stubs.c: remove duplicated include
  ocfs2: remove redundant assignment to variable bit_off
  watchdog/hardlockup: fix typo in config HARDLOCKUP_DETECTOR_PREFER_BUDDY
  powerpc: move arch_trigger_cpumask_backtrace from nmi.h to irq.h
  devres: show which resource was invalid in __devm_ioremap_resource()
  watchdog/hardlockup: define HARDLOCKUP_DETECTOR_ARCH
  watchdog/sparc64: define HARDLOCKUP_DETECTOR_SPARC64
  watchdog/hardlockup: make HAVE_NMI_WATCHDOG sparc64-specific
  watchdog/hardlockup: declare arch_touch_nmi_watchdog() only in linux/nmi.h
  watchdog/hardlockup: make the config checks more straightforward
  watchdog/hardlockup: sort hardlockup detector related config values a logical way
  watchdog/hardlockup: move SMP barriers from common code to buddy code
  watchdog/buddy: simplify the dependency for HARDLOCKUP_DETECTOR_PREFER_BUDDY
  watchdog/buddy: don't copy the cpumask in watchdog_next_cpu()
  watchdog/buddy: cleanup how watchdog_buddy_check_hardlockup() is called
  watchdog/hardlockup: remove softlockup comment in touch_nmi_watchdog()
  watchdog/hardlockup: in watchdog_hardlockup_check() use cpumask_copy()
  watchdog/hardlockup: don't use raw_cpu_ptr() in watchdog_hardlockup_kick()
  watchdog/hardlockup: HAVE_NMI_WATCHDOG must implement watchdog_hardlockup_probe()
  watchdog/hardlockup: keep kernel.nmi_watchdog sysctl as 0444 if probe fails
  ...
2023-06-28 10:59:38 -07:00
Linus Torvalds
6e17c6de3d Merge tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull mm updates from Andrew Morton:

 - Yosry Ahmed brought back some cgroup v1 stats in OOM logs

 - Yosry has also eliminated cgroup's atomic rstat flushing

 - Nhat Pham adds the new cachestat() syscall. It provides userspace
   with the ability to query pagecache status - a similar concept to
   mincore() but more powerful and with improved usability

 - Mel Gorman provides more optimizations for compaction, reducing the
   prevalence of page rescanning

 - Lorenzo Stoakes has done some maintanance work on the
   get_user_pages() interface

 - Liam Howlett continues with cleanups and maintenance work to the
   maple tree code. Peng Zhang also does some work on maple tree

 - Johannes Weiner has done some cleanup work on the compaction code

 - David Hildenbrand has contributed additional selftests for
   get_user_pages()

 - Thomas Gleixner has contributed some maintenance and optimization
   work for the vmalloc code

 - Baolin Wang has provided some compaction cleanups,

 - SeongJae Park continues maintenance work on the DAMON code

 - Huang Ying has done some maintenance on the swap code's usage of
   device refcounting

 - Christoph Hellwig has some cleanups for the filemap/directio code

 - Ryan Roberts provides two patch series which yield some
   rationalization of the kernel's access to pte entries - use the
   provided APIs rather than open-coding accesses

 - Lorenzo Stoakes has some fixes to the interaction between pagecache
   and directio access to file mappings

 - John Hubbard has a series of fixes to the MM selftesting code

 - ZhangPeng continues the folio conversion campaign

 - Hugh Dickins has been working on the pagetable handling code, mainly
   with a view to reducing the load on the mmap_lock

 - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment
   from 128 to 8

 - Domenico Cerasuolo has improved the zswap reclaim mechanism by
   reorganizing the LRU management

 - Matthew Wilcox provides some fixups to make gfs2 work better with the
   buffer_head code

 - Vishal Moola also has done some folio conversion work

 - Matthew Wilcox has removed the remnants of the pagevec code - their
   functionality is migrated over to struct folio_batch

* tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (380 commits)
  mm/hugetlb: remove hugetlb_set_page_subpool()
  mm: nommu: correct the range of mmap_sem_read_lock in task_mem()
  hugetlb: revert use of page_cache_next_miss()
  Revert "page cache: fix page_cache_next/prev_miss off by one"
  mm/vmscan: fix root proactive reclaim unthrottling unbalanced node
  mm: memcg: rename and document global_reclaim()
  mm: kill [add|del]_page_to_lru_list()
  mm: compaction: convert to use a folio in isolate_migratepages_block()
  mm: zswap: fix double invalidate with exclusive loads
  mm: remove unnecessary pagevec includes
  mm: remove references to pagevec
  mm: rename invalidate_mapping_pagevec to mapping_try_invalidate
  mm: remove struct pagevec
  net: convert sunrpc from pagevec to folio_batch
  i915: convert i915_gpu_error to use a folio_batch
  pagevec: rename fbatch_count()
  mm: remove check_move_unevictable_pages()
  drm: convert drm_gem_put_pages() to use a folio_batch
  i915: convert shmem_sg_free_table() to use a folio_batch
  scatterlist: add sg_set_folio()
  ...
2023-06-28 10:28:11 -07:00
Linus Torvalds
72dc6db7e3 Merge tag 'wq-for-6.5-cleanup-ordered' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull ordered workqueue creation updates from Tejun Heo:
 "For historical reasons, unbound workqueues with max concurrency limit
  of 1 are considered ordered, even though the concurrency limit hasn't
  been system-wide for a long time.

  This creates ambiguity around whether ordered execution is actually
  required for correctness, which was actually confusing for e.g. btrfs
  (btrfs updates are being routed through the btrfs tree).

  There aren't that many users in the tree which use the combination and
  there are pending improvements to unbound workqueue affinity handling
  which will make inadvertent use of ordered workqueue a bigger loss.

  This clarifies the situation for most of them by updating the ones
  which require ordered execution to use alloc_ordered_workqueue().

  There are some conversions being routed through subsystem-specific
  trees and likely a few stragglers. Once they're all converted,
  workqueue can trigger a warning on unbound + @max_active==1 usages and
  eventually drop the implicit ordered behavior"

* tag 'wq-for-6.5-cleanup-ordered' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  rxrpc: Use alloc_ordered_workqueue() to create ordered workqueues
  net: qrtr: Use alloc_ordered_workqueue() to create ordered workqueues
  net: wwan: t7xx: Use alloc_ordered_workqueue() to create ordered workqueues
  dm integrity: Use alloc_ordered_workqueue() to create ordered workqueues
  media: amphion: Use alloc_ordered_workqueue() to create ordered workqueues
  scsi: NCR5380: Use default @max_active for hostdata->work_q
  media: coda: Use alloc_ordered_workqueue() to create ordered workqueues
  crypto: octeontx2: Use alloc_ordered_workqueue() to create ordered workqueues
  wifi: ath10/11/12k: Use alloc_ordered_workqueue() to create ordered workqueues
  wifi: mwifiex: Use default @max_active for workqueues
  wifi: iwlwifi: Use default @max_active for trans_pcie->rba.alloc_wq
  xen/pvcalls: Use alloc_ordered_workqueue() to create ordered workqueues
  virt: acrn: Use alloc_ordered_workqueue() to create ordered workqueues
  net: octeontx2: Use alloc_ordered_workqueue() to create ordered workqueues
  net: thunderx: Use alloc_ordered_workqueue() to create ordered workqueues
  greybus: Use alloc_ordered_workqueue() to create ordered workqueues
  powerpc, workqueue: Use alloc_ordered_workqueue() to create ordered workqueues
2023-06-27 16:46:06 -07:00
Linus Torvalds
6f612579be Merge tag 'objtool-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molar:
 "Build footprint & performance improvements:

   - Reduce memory usage with CONFIG_DEBUG_INFO=y

     In the worst case of an allyesconfig+CONFIG_DEBUG_INFO=y kernel,
     DWARF creates almost 200 million relocations, ballooning objtool's
     peak heap usage to 53GB. These patches reduce that to 25GB.

     On a distro-type kernel with kernel IBT enabled, they reduce
     objtool's peak heap usage from 4.2GB to 2.8GB.

     These changes also improve the runtime significantly.

  Debuggability improvements:

   - Add the unwind_debug command-line option, for more extend unwinding
     debugging output
   - Limit unreachable warnings to once per function
   - Add verbose option for disassembling affected functions
   - Include backtrace in verbose mode
   - Detect missing __noreturn annotations
   - Ignore exc_double_fault() __noreturn warnings
   - Remove superfluous global_noreturns entries
   - Move noreturn function list to separate file
   - Add __kunit_abort() to noreturns

  Unwinder improvements:

   - Allow stack operations in UNWIND_HINT_UNDEFINED regions
   - drm/vmwgfx: Add unwind hints around RBP clobber

  Cleanups:

   - Move the x86 entry thunk restore code into thunk functions
   - x86/unwind/orc: Use swap() instead of open coding it
   - Remove unnecessary/unused variables

  Fixes for modern stack canary handling"

* tag 'objtool-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits)
  x86/orc: Make the is_callthunk() definition depend on CONFIG_BPF_JIT=y
  objtool: Skip reading DWARF section data
  objtool: Free insns when done
  objtool: Get rid of reloc->rel[a]
  objtool: Shrink elf hash nodes
  objtool: Shrink reloc->sym_reloc_entry
  objtool: Get rid of reloc->jump_table_start
  objtool: Get rid of reloc->addend
  objtool: Get rid of reloc->type
  objtool: Get rid of reloc->offset
  objtool: Get rid of reloc->idx
  objtool: Get rid of reloc->list
  objtool: Allocate relocs in advance for new rela sections
  objtool: Add for_each_reloc()
  objtool: Don't free memory in elf_close()
  objtool: Keep GElf_Rel[a] structs synced
  objtool: Add elf_create_section_pair()
  objtool: Add mark_sec_changed()
  objtool: Fix reloc_hash size
  objtool: Consolidate rel/rela handling
  ...
2023-06-27 15:05:41 -07:00
Linus Torvalds
bc6cb4d5bc Merge tag 'locking-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:

 - Introduce cmpxchg128() -- aka. the demise of cmpxchg_double()

   The cmpxchg128() family of functions is basically & functionally the
   same as cmpxchg_double(), but with a saner interface.

   Instead of a 6-parameter horror that forced u128 - u64/u64-halves
   layout details on the interface and exposed users to complexity,
   fragility & bugs, use a natural 3-parameter interface with u128
   types.

 - Restructure the generated atomic headers, and add kerneldoc comments
   for all of the generic atomic{,64,_long}_t operations.

   The generated definitions are much cleaner now, and come with
   documentation.

 - Implement lock_set_cmp_fn() on lockdep, for defining an ordering when
   taking multiple locks of the same type.

   This gets rid of one use of lockdep_set_novalidate_class() in the
   bcache code.

 - Fix raw_cpu_generic_try_cmpxchg() bug due to an unintended variable
   shadowing generating garbage code on Clang on certain ARM builds.

* tag 'locking-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (43 commits)
  locking/atomic: scripts: fix ${atomic}_dec_if_positive() kerneldoc
  percpu: Fix self-assignment of __old in raw_cpu_generic_try_cmpxchg()
  locking/atomic: treewide: delete arch_atomic_*() kerneldoc
  locking/atomic: docs: Add atomic operations to the driver basic API documentation
  locking/atomic: scripts: generate kerneldoc comments
  docs: scripts: kernel-doc: accept bitwise negation like ~@var
  locking/atomic: scripts: simplify raw_atomic*() definitions
  locking/atomic: scripts: simplify raw_atomic_long*() definitions
  locking/atomic: scripts: split pfx/name/sfx/order
  locking/atomic: scripts: restructure fallback ifdeffery
  locking/atomic: scripts: build raw_atomic_long*() directly
  locking/atomic: treewide: use raw_atomic*_<op>()
  locking/atomic: scripts: add trivial raw_atomic*_<op>()
  locking/atomic: scripts: factor out order template generation
  locking/atomic: scripts: remove leftover "${mult}"
  locking/atomic: scripts: remove bogus order parameter
  locking/atomic: xtensa: add preprocessor symbols
  locking/atomic: x86: add preprocessor symbols
  locking/atomic: sparc: add preprocessor symbols
  locking/atomic: sh: add preprocessor symbols
  ...
2023-06-27 14:14:30 -07:00
Timothy Pearson
bfd8d98921 powerpc/iommu: Only build sPAPR access functions on pSeries
and PowerNV

A build failure with CONFIG_HAVE_PCI=y set without PSERIES or POWERNV
set was caught by the random configuration checker.  Guard the sPAPR
specific IOMMU functions on CONFIG_PPC_PSERIES || CONFIG_PPC_POWERNV.

Signed-off-by: Timothy Pearson <tpearson@raptorengineering.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/2015925968.3546872.1685990936823.JavaMail.zimbra@raptorengineeringinc.com
2023-06-21 15:13:57 +10:00
Rohan McLure
8608f14b49 powerpc: Annotate accesses to ipi message flags
IPI message flags are observed and consequently consumed in the
smp_ipi_demux_relaxed function, which handles these message sources
until it observes none more arriving. Mark the checked loop guard with
READ_ONCE, to signal to KCSAN that the read is known to be volatile, and
that non-determinism is expected. Mark write for message source in
smp_muxed_ipi_set_message().

Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230510033117.1395895-8-rmclure@linux.ibm.com
2023-06-21 15:13:57 +10:00
Rohan McLure
be286b8637 powerpc: Mark [h]ssr_valid accesses in check_return_regs_valid
Checks to see if the [H]SRR registers have been clobbered by (soft)
NMI interrupts imply the possibility for a data race on the
[h]srr_valid entries in the PACA. Annotate accesses to these fields with
READ_ONCE, removing the need for the barrier.

The diagnostic can use plain-access reads and writes, but annotate with
data_race.

Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230510033117.1395895-5-rmclure@linux.ibm.com
2023-06-21 15:13:57 +10:00
Aditya Gupta
b684c09f09 powerpc: update ppc_save_regs to save current r1 in pt_regs
ppc_save_regs() skips one stack frame while saving the CPU register states.
Instead of saving current R1, it pulls the previous stack frame pointer.

When vmcores caused by direct panic call (such as `echo c >
/proc/sysrq-trigger`), are debugged with gdb, gdb fails to show the
backtrace correctly. On further analysis, it was found that it was because
of mismatch between r1 and NIP.

GDB uses NIP to get current function symbol and uses corresponding debug
info of that function to unwind previous frames, but due to the
mismatching r1 and NIP, the unwinding does not work, and it fails to
unwind to the 2nd frame and hence does not show the backtrace.

GDB backtrace with vmcore of kernel without this patch:

---------
(gdb) bt
 #0  0xc0000000002a53e8 in crash_setup_regs (oldregs=<optimized out>,
    newregs=0xc000000004f8f8d8) at ./arch/powerpc/include/asm/kexec.h:69
 #1  __crash_kexec (regs=<optimized out>) at kernel/kexec_core.c:974
 #2  0x0000000000000063 in ?? ()
 #3  0xc000000003579320 in ?? ()
---------

Further analysis revealed that the mismatch occurred because
"ppc_save_regs" was saving the previous stack's SP instead of the current
r1. This patch fixes this by storing current r1 in the saved pt_regs.

GDB backtrace with vmcore of patched kernel:

--------
(gdb) bt
 #0  0xc0000000002a53e8 in crash_setup_regs (oldregs=0x0, newregs=0xc00000000670b8d8)
    at ./arch/powerpc/include/asm/kexec.h:69
 #1  __crash_kexec (regs=regs@entry=0x0) at kernel/kexec_core.c:974
 #2  0xc000000000168918 in panic (fmt=fmt@entry=0xc000000001654a60 "sysrq triggered crash\n")
    at kernel/panic.c:358
 #3  0xc000000000b735f8 in sysrq_handle_crash (key=<optimized out>) at drivers/tty/sysrq.c:155
 #4  0xc000000000b742cc in __handle_sysrq (key=key@entry=99, check_mask=check_mask@entry=false)
    at drivers/tty/sysrq.c:602
 #5  0xc000000000b7506c in write_sysrq_trigger (file=<optimized out>, buf=<optimized out>,
    count=2, ppos=<optimized out>) at drivers/tty/sysrq.c:1163
 #6  0xc00000000069a7bc in pde_write (ppos=<optimized out>, count=<optimized out>,
    buf=<optimized out>, file=<optimized out>, pde=0xc00000000362cb40) at fs/proc/inode.c:340
 #7  proc_reg_write (file=<optimized out>, buf=<optimized out>, count=<optimized out>,
    ppos=<optimized out>) at fs/proc/inode.c:352
 #8  0xc0000000005b3bbc in vfs_write (file=file@entry=0xc000000006aa6b00,
    buf=buf@entry=0x61f498b4f60 <error: Cannot access memory at address 0x61f498b4f60>,
    count=count@entry=2, pos=pos@entry=0xc00000000670bda0) at fs/read_write.c:582
 #9  0xc0000000005b4264 in ksys_write (fd=<optimized out>,
    buf=0x61f498b4f60 <error: Cannot access memory at address 0x61f498b4f60>, count=2)
    at fs/read_write.c:637
 #10 0xc00000000002ea2c in system_call_exception (regs=0xc00000000670be80, r0=<optimized out>)
    at arch/powerpc/kernel/syscall.c:171
 #11 0xc00000000000c270 in system_call_vectored_common ()
    at arch/powerpc/kernel/interrupt_64.S:192
--------

Nick adds:
  So this now saves regs as though it was an interrupt taken in the
  caller, at the instruction after the call to ppc_save_regs, whereas
  previously the NIP was there, but R1 came from the caller's caller and
  that mismatch is what causes gdb's dwarf unwinder to go haywire.

Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
Fixes: d16a58f885 ("powerpc: Improve ppc_save_regs()")
Reivewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230615091047.90433-1-adityag@linux.ibm.com
2023-06-19 17:37:14 +10:00
Benjamin Gray
97228ca375 powerpc/ptrace: Expose HASHKEYR register to ptrace
The HASHKEYR register contains a secret per-process key to enable unique
hashes per process. In general it should not be exposed to userspace
at all and a regular process has no need to know its key.

However, checkpoint restore in userspace (CRIU) functionality requires
that a process be able to set the HASHKEYR of another process, otherwise
existing hashes on the stack would be invalidated by a new random key.

Exposing HASHKEYR in this way also makes it appear in core dumps, which
is a security concern. Multiple threads may share a key, for example
just after a fork() call, where the kernel cannot know if the child is
going to return back along the parent's stack. If such a thread is
coerced into making a core dump, then the HASHKEYR value will be
readable and able to be used against all other threads sharing that key,
effectively undoing any protection offered by hashst/hashchk.

Therefore we expose HASHKEYR to ptrace when CONFIG_CHECKPOINT_RESTORE is
enabled, providing a choice of increased security or migratable ROP
protected processes. This is similar to how ARM exposes its PAC keys.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Reviewed-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230616034846.311705-8-bgray@linux.ibm.com
2023-06-19 17:36:27 +10:00
Benjamin Gray
884ad5c52d powerpc/ptrace: Expose DEXCR and HDEXCR registers to ptrace
The DEXCR register is of interest when ptracing processes. Currently it
is static, but eventually will be dynamically controllable by a process.
If a process can control its own, then it is useful for it to be
ptrace-able to (e.g., for checkpoint-restore functionality).

It is also relevant to core dumps (the NPHIE aspect in particular),
which use the ptrace mechanism (or is it the other way around?) to
decide what to dump. The HDEXCR is useful here too, as the NPHIE aspect
may be set in the HDEXCR without being set in the DEXCR. Although the
HDEXCR is per-cpu and we don't track it in the task struct (it's useless
in normal operation), it would be difficult to imagine why a hypervisor
would set it to different values within a guest. A hypervisor cannot
safely set NPHIE differently at least, as that would break programs.

Expose a read-only view of the userspace DEXCR and HDEXCR to ptrace.
The HDEXCR is always readonly, and is useful for diagnosing the core
dumps (as the HDEXCR may set NPHIE without the DEXCR setting it).

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Reviewed-by: Russell Currey <ruscur@russell.cc>
[mpe: Use lower_32_bits() rather than open coding]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230616034846.311705-7-bgray@linux.ibm.com
2023-06-19 17:36:26 +10:00
Benjamin Gray
be98fcf7c1 powerpc/dexcr: Support userspace ROP protection
The ISA 3.1B hashst and hashchk instructions use a per-cpu SPR HASHKEYR
to hold a key used in the hash calculation. This key should be different
for each process to make it harder for a malicious process to recreate
valid hash values for a victim process.

Add support for storing a per-thread hash key, and setting/clearing
HASHKEYR appropriately.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Reviewed-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230616034846.311705-6-bgray@linux.ibm.com
2023-06-19 17:36:26 +10:00
Benjamin Gray
5bcba4e6c1 powerpc/dexcr: Handle hashchk exception
Recognise and pass the appropriate signal to the user program when a
hashchk instruction triggers. This is independent of allowing
configuration of DEXCR[NPHIE], as a hypervisor can enforce this aspect
regardless of the kernel.

The signal mirrors how ARM reports their similar check failure. For
example, their FPAC handler in arch/arm64/kernel/traps.c do_el0_fpac()
does this. When we fail to read the instruction that caused the fault
we send a segfault, similar to how emulate_math() does it.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230616034846.311705-5-bgray@linux.ibm.com
2023-06-19 17:36:26 +10:00
Benjamin Gray
0ffd60b782 powerpc/dexcr: Add initial Dynamic Execution Control Register (DEXCR) support
ISA 3.1B introduces the Dynamic Execution Control Register (DEXCR). It
is a per-cpu register that allows control over various CPU behaviours
including branch hint usage, indirect branch speculation, and
hashst/hashchk support.

Add some definitions and basic support for the DEXCR in the kernel.
Right now it just

  * Initialises the DEXCR and HASHKEYR to a fixed value when a CPU
    onlines.
  * Clears them in reset_sprs().
  * Detects when the NPHIE aspect is supported (the others don't get
    looked at in this series, so there's no need to waste a CPU_FTR
    on them).

We initialise the HASHKEYR to ensure that all cores have the same key,
so an HV enforced NPHIE + swapping cores doesn't randomly crash a
process using hash instructions. The stores to HASHKEYR are
unconditional because the ISA makes no mention of the SPR being missing
if support for doing the hashes isn't present. So all that would happen
is the HASHKEYR value gets ignored. This helps slightly if NPHIE
detection fails; e.g., we currently only detect it on pseries.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
[mpe: Use simple values for DEXCR constants]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230616034846.311705-4-bgray@linux.ibm.com
2023-06-19 17:36:25 +10:00
Benjamin Gray
81e30a5412 powerpc/ptrace: Add missing <linux/regset.h> include
ptrace-decl.h uses user_regset_get2_fn (among other things) from
regset.h. While all current users of ptrace-decl.h include regset.h
before it anyway, it adds an implicit ordering dependency and breaks
source tooling that tries to inspect ptrace-decl.h by itself.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Reviewed-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230616034846.311705-3-bgray@linux.ibm.com
2023-06-19 17:36:25 +10:00
Nicholas Piggin
8ad57add77 powerpc/build: vdso linker warning for orphan sections
Add --orphan-handlin for vdsos, and adjust vdso linker scripts to deal
with orphan sections.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230609051002.3342-1-npiggin@gmail.com
2023-06-15 14:04:19 +10:00
Nicholas Piggin
27be245633 powerpc/64: Rename entry_64.S to prom_entry_64.S
This file contains only the enter_prom implementation now.
Trim includes and update header comment while we're here.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230606132447.315714-7-npiggin@gmail.com
2023-06-15 14:04:19 +10:00
Nicholas Piggin
afc6386815 powerpc: merge 32-bit and 64-bit _switch implementation
The _switch stack frame setup are substantially the same, so are the
comments. The difference in how the stack and current are switched,
and other hardware and software housekeeping is done is moved into
macros.

Generated code should be unchanged.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Tweak include orer to fix compile errors on some configs]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230606132447.315714-6-npiggin@gmail.com
2023-06-15 14:03:55 +10:00
Maciej W. Rozycki
1541a21305 powerpc/eeh: Rely on dev->link_active_reporting
Use dev->link_active_reporting to determine whether Data Link Layer Link
Active Reporting is available rather than re-retrieving the capability.

Link: https://lore.kernel.org/r/alpine.DEB.2.21.2305310124100.59226@angie.orcam.me.uk
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-14 17:58:12 -05:00
Nicholas Piggin
6958ad05d5 powerpc/32: Rearrange _switch to prepare for 32/64 merge
Change the order of some operations and change some register numbers in
preparation to merge 32-bit and 64-bit switch.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230606132447.315714-5-npiggin@gmail.com
2023-06-14 12:46:42 +10:00
Nicholas Piggin
fc8562c9b6 powerpc/32: Remove sync from _switch
64-bit has removed the sync from _switch since commit 9145effd62
("powerpc/64: Drop explicit hwsync in context switch"). The same
logic there should apply to 32-bit. Remove the sync and replace with
a placeholder comment (32 and 64 will be merged with a later change).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230606132447.315714-4-npiggin@gmail.com
2023-06-14 12:46:42 +10:00
Nicholas Piggin
0eb8088b5a powerpc/64: Rearrange 64-bit _switch to prepare for 32/64 merge
More some 64-bit specifics out from the function epilogue and rearrange
this to be a bit neater, use 32-bit mem ops for CR save/restore, and
change some register numbers.

This is preparation to consolidate 32-bit and 64-bit switch code.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230606132447.315714-3-npiggin@gmail.com
2023-06-14 12:46:42 +10:00
Nicholas Piggin
d6b87c3eb6 powerpc/64s: move stack SLB pinning out of line from _switch
The large hunk of SLB pinning in _switch asm code makes it more
difficult to see everything else that's going on. It is a less important
path now, so icache and fetch footprint overhead can be avoided.

Move context switch stack SLB pinning out of line.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230606132447.315714-2-npiggin@gmail.com
2023-06-14 12:46:42 +10:00
Uwe Kleine-König
1eea99c045 powerpc/legacy_serial: Handle SERIAL_8250_FSL=n build failures
With SERIAL_8250=y and SERIAL_8250_FSL_CONSOLE=n the both
IS_ENABLED(CONFIG_SERIAL_8250) and IS_REACHABLE(CONFIG_SERIAL_8250)
evaluate to true and so fsl8250_handle_irq() is used. However this
function is only available if CONFIG_SERIAL_8250_CONSOLE=y (and thus
SERIAL_8250_FSL=y).

To prepare SERIAL_8250_FSL becoming tristate and being enabled in more
cases, check for IS_REACHABLE(CONFIG_SERIAL_8250_FSL) before making use
of fsl8250_handle_irq(). This check is correct with and without the
change to make SERIAL_8250_FSL modular.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Fixes: 66eff0ef52 ("powerpc/legacy_serial: Warn about 8250 devices operated without active FSL workarounds")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Message-ID: <20230609133932.786117-2-u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 12:27:04 +02:00
Douglas Anderson
df95d3085c watchdog/hardlockup: rename some "NMI watchdog" constants/function
Do a search and replace of:
- NMI_WATCHDOG_ENABLED => WATCHDOG_HARDLOCKUP_ENABLED
- SOFT_WATCHDOG_ENABLED => WATCHDOG_SOFTOCKUP_ENABLED
- watchdog_nmi_ => watchdog_hardlockup_
- nmi_watchdog_available => watchdog_hardlockup_available
- nmi_watchdog_user_enabled => watchdog_hardlockup_user_enabled
- soft_watchdog_user_enabled => watchdog_softlockup_user_enabled
- NMI_WATCHDOG_DEFAULT => WATCHDOG_HARDLOCKUP_DEFAULT

Then update a few comments near where names were changed.

This is specifically to make it less confusing when we want to introduce
the buddy hardlockup detector, which isn't using NMIs.  As part of this,
we sanitized a few names for consistency.

[trix@redhat.com: make variables static]
  Link: https://lkml.kernel.org/r/20230525162822.1.I0fb41d138d158c9230573eaa37dc56afa2fb14ee@changeid
Link: https://lkml.kernel.org/r/20230519101840.v5.12.I91f7277bab4bf8c0cb238732ed92e7ce7bbd71a6@changeid
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Tom Rix <trix@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Colin Cross <ccross@android.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masayoshi Mizuma <msys.mizuma@gmail.com>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Sumit Garg <sumit.garg@linaro.org>
Cc: Tzung-Bi Shih <tzungbi@chromium.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 17:44:20 -07:00
Nhat Pham
946e697c69 cachestat: wire up cachestat for other architectures
cachestat is previously only wired in for x86 (and architectures using
the generic unistd.h table):

https://lore.kernel.org/lkml/20230503013608.2431726-1-nphamcs@gmail.com/

This patch wires cachestat in for all the other architectures.

[nphamcs@gmail.com: wire up cachestat for arm64]
  Link: https://lkml.kernel.org/r/20230511092843.3896327-1-nphamcs@gmail.com
Link: https://lkml.kernel.org/r/20230510195806.2902878-1-nphamcs@gmail.com
Signed-off-by: Nhat Pham <nphamcs@gmail.com>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>	[powerpc]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Heiko Carstens <hca@linux.ibm.com>		[s390]
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Chris Zankel <chris@zankel.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:16 -07:00
Christophe Leroy
a03b1a0b19 powerpc/signal32: Force inlining of __unsafe_save_user_regs() and save_tm_user_regs_unsafe()
Looking at generated code for handle_signal32() shows calls to a
function called __unsafe_save_user_regs.constprop.0 while user access
is open.

And that __unsafe_save_user_regs.constprop.0 function has two nops at
the begining, allowing it to be traced, which is unexpected during
user access open window.

The solution could be to mark __unsafe_save_user_regs() no trace, but
to be on the safe side the most efficient is to flag it __always_inline
as already done for function __unsafe_restore_general_regs(). The
function is relatively small and only called twice, so the size
increase will remain in the noise.

Do the same with save_tm_user_regs_unsafe() as it may suffer the
same issue.

Fixes: ef75e73182 ("powerpc/signal32: Transform save_user_regs() and save_tm_user_regs() in 'unsafe' version")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/7e469c8f01860a69c1ada3ca6a5e2aa65f0f74b2.1685955220.git.christophe.leroy@csgroup.eu
2023-06-09 23:29:51 +10:00
Christophe Leroy
0eb089a72f powerpc/interrupt: Don't read MSR from interrupt_exit_kernel_prepare()
A disassembly of interrupt_exit_kernel_prepare() shows a useless read
of MSR register. This is shown by r9 being re-used immediately without
doing anything with the value read.

  c000e0e0:       60 00 00 00     nop
  c000e0e4:       7d 3a c2 a6     mfmd_ap r9
  c000e0e8:       7d 20 00 a6     mfmsr   r9
  c000e0ec:       7c 51 13 a6     mtspr   81,r2
  c000e0f0:       81 3f 00 84     lwz     r9,132(r31)
  c000e0f4:       71 29 80 00     andi.   r9,r9,32768

This is due to the use of local_irq_save(). The flags read by
local_irq_save() are never used, use local_irq_disable() instead.

Fixes: 13799748b9 ("powerpc/64: use interrupt restart table to speed up return from interrupt")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/df36c6205ab64326fb1b991993c82057e92ace2f.1685955214.git.christophe.leroy@csgroup.eu
2023-06-09 23:29:51 +10:00