linux-stable.git/arch/powerpc/include, branch v5.4.239

powerpc/imc-pmu: Fix use of mutex in IRQs disabled section

2023-01-18T10:42:03+00:00

commit 76d588dddc459fefa1da96e0a081a397c5c8e216 upstream.

Current imc-pmu code triggers a WARNING with CONFIG_DEBUG_ATOMIC_SLEEP
and CONFIG_PROVE_LOCKING enabled, while running a thread_imc event.

Command to trigger the warning:
  # perf stat -e thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ sleep 5

   Performance counter stats for 'sleep 5':

                   0      thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/

         5.002117947 seconds time elapsed

         0.000131000 seconds user
         0.001063000 seconds sys

Below is snippet of the warning in dmesg:

  BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
  in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 2869, name: perf-exec
  preempt_count: 2, expected: 0
  4 locks held by perf-exec/2869:
   #0: c00000004325c540 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0x64/0xa90
   #1: c00000004325c5d8 (&sig->exec_update_lock){++++}-{3:3}, at: begin_new_exec+0x460/0xef0
   #2: c0000003fa99d4e0 (&cpuctx_lock){-...}-{2:2}, at: perf_event_exec+0x290/0x510
   #3: c000000017ab8418 (&ctx->lock){....}-{2:2}, at: perf_event_exec+0x29c/0x510
  irq event stamp: 4806
  hardirqs last  enabled at (4805): [] _raw_spin_unlock_irqrestore+0x94/0xd0
  hardirqs last disabled at (4806): [] perf_event_exec+0x394/0x510
  softirqs last  enabled at (0): [] copy_process+0xc34/0x1ff0
  softirqs last disabled at (0): [<0000000000000000>] 0x0
  CPU: 36 PID: 2869 Comm: perf-exec Not tainted 6.2.0-rc2-00011-g1247637727f2 #61
  Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
  Call Trace:
    dump_stack_lvl+0x98/0xe0 (unreliable)
    __might_resched+0x2f8/0x310
    __mutex_lock+0x6c/0x13f0
    thread_imc_event_add+0xf4/0x1b0
    event_sched_in+0xe0/0x210
    merge_sched_in+0x1f0/0x600
    visit_groups_merge.isra.92.constprop.166+0x2bc/0x6c0
    ctx_flexible_sched_in+0xcc/0x140
    ctx_sched_in+0x20c/0x2a0
    ctx_resched+0x104/0x1c0
    perf_event_exec+0x340/0x510
    begin_new_exec+0x730/0xef0
    load_elf_binary+0x3f8/0x1e10
  ...
  do not call blocking ops when !TASK_RUNNING; state=2001 set at [<00000000fd63e7cf>] do_nanosleep+0x60/0x1a0
  WARNING: CPU: 36 PID: 2869 at kernel/sched/core.c:9912 __might_sleep+0x9c/0xb0
  CPU: 36 PID: 2869 Comm: sleep Tainted: G        W          6.2.0-rc2-00011-g1247637727f2 #61
  Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
  NIP:  c000000000194a1c LR: c000000000194a18 CTR: c000000000a78670
  REGS: c00000004d2134e0 TRAP: 0700   Tainted: G        W           (6.2.0-rc2-00011-g1247637727f2)
  MSR:  9000000000021033   CR: 48002824  XER: 00000000
  CFAR: c00000000013fb64 IRQMASK: 1

The above warning triggered because the current imc-pmu code uses mutex
lock in interrupt disabled sections. The function mutex_lock()
internally calls __might_resched(), which will check if IRQs are
disabled and in case IRQs are disabled, it will trigger the warning.

Fix the issue by changing the mutex lock to spinlock.

Fixes: 8f95faaac56c ("powerpc/powernv: Detect and create IMC device")
Reported-by: Michael Petlan 
Reported-by: Peter Zijlstra 
Signed-off-by: Kajol Jain 
[mpe: Fix comments, trim oops in change log, add reported-by tags]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20230106065157.182648-1-kjain@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman

powerpc/bpf: Fix use of user_pt_regs in uapi

2022-07-07T15:36:48+00:00

commit b21bd5a4b130f8370861478d2880985daace5913 upstream.

Trying to build a .c file that includes :
  $ cat test_bpf_headers.c
  #include 

throws the below error:
  /usr/include/linux/bpf_perf_event.h:14:28: error: field ‘regs’ has incomplete type
     14 |         bpf_user_pt_regs_t regs;
	|                            ^~~~

This is because we typedef bpf_user_pt_regs_t to 'struct user_pt_regs'
in arch/powerpc/include/uaps/asm/bpf_perf_event.h, but 'struct
user_pt_regs' is not exposed to userspace.

Powerpc has both pt_regs and user_pt_regs structures. However, unlike
arm64 and s390, we expose user_pt_regs to userspace as just 'pt_regs'.
As such, we should typedef bpf_user_pt_regs_t to 'struct pt_regs' for
userspace.

Within the kernel though, we want to typedef bpf_user_pt_regs_t to
'struct user_pt_regs'.

Remove arch/powerpc/include/uapi/asm/bpf_perf_event.h so that the
uapi/asm-generic version of the header is exposed to userspace.
Introduce arch/powerpc/include/asm/bpf_perf_event.h so that we can
typedef bpf_user_pt_regs_t to 'struct user_pt_regs' for use within the
kernel.

Note that this was not showing up with the bpf selftest build since
tools/include/uapi/asm/bpf_perf_event.h didn't include the powerpc
variant.

Fixes: a6460b03f945ee ("powerpc/bpf: Fix broken uapi for BPF_PROG_TYPE_PERF_EVENT")
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: Naveen N. Rao 
[mpe: Use typical naming for header include guard]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220627191119.142867-1-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman

powerpc/ftrace: Remove ftrace init tramp once kernel init is complete

2022-07-02T14:28:49+00:00

commit 84ade0a6655bee803d176525ef457175cbf4df22 upstream.

Stop using the ftrace trampoline for init section once kernel init is
complete.

Fixes: 67361cf8071286 ("powerpc/ftrace: Handle large kernel configs")
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: Naveen N. Rao 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220516071422.463738-1-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman

powerpc/mm: Switch obsolete dssall to .long

2022-06-22T12:11:24+00:00

commit d51f86cfd8e378d4907958db77da3074f6dce3ba upstream.

The dssall ("Data Stream Stop All") instruction is obsolete altogether
with other Data Cache Instructions since ISA 2.03 (year 2006).

LLVM IAS does not support it but PPC970 seems to be using it.
This switches dssall to .long as there is no much point in fixing LLVM.

Signed-off-by: Alexey Kardashevskiy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20211221055904.555763-6-aik@ozlabs.ru
[sudip: adjust context]
Signed-off-by: Sudip Mukherjee 
Signed-off-by: Greg Kroah-Hartman

powerpc: define get_cycles macro for arch-override

2022-06-22T12:11:15+00:00

commit 408835832158df0357e18e96da7f2d1ed6b80e7f upstream.

PowerPC defines a get_cycles() function, but it does not do the usual
`#define get_cycles get_cycles` dance, making it impossible for generic
code to see if an arch-specific function was defined. While the
get_cycles() ifdef is not currently used, the following timekeeping
patch in this series will depend on the macro existing (or not existing)
when defining random_get_entropy().

Cc: Thomas Gleixner 
Cc: Arnd Bergmann 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Acked-by: Michael Ellerman 
Signed-off-by: Jason A. Donenfeld 
Signed-off-by: Greg Kroah-Hartman

powerpc: Use bool in archrandom.h

2022-06-22T12:11:05+00:00

commit 98dcfce69729f9ce0fb14f96a39bbdba21429597 upstream.

The generic interface uses bool not int; match that.

Reviewed-by: Ard Biesheuvel 
Signed-off-by: Richard Henderson 
Signed-off-by: Mark Brown 
Link: https://lore.kernel.org/r/20200110145422.49141-9-broonie@kernel.org
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jason A. Donenfeld 
Signed-off-by: Greg Kroah-Hartman

powerpc: Remove arch_has_random, arch_has_random_seed

2022-06-22T12:11:04+00:00

commit cbac004995a0ce8453bdc555fab579e2bdb842a6 upstream.

These symbols are currently part of the generic archrandom.h
interface, but are currently unused and can be removed.

Signed-off-by: Richard Henderson 
Signed-off-by: Mark Brown 
Link: https://lore.kernel.org/r/20200110145422.49141-3-broonie@kernel.org
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jason A. Donenfeld 
Signed-off-by: Greg Kroah-Hartman

powerpc/64: Only WARN if pa()/va() called with bad addresses

2022-06-14T16:11:42+00:00

[ Upstream commit c4bce84d0bd3f396f702d69be2e92bbd8af97583 ]

We added checks to __pa() / __va() to ensure they're only called with
appropriate addresses. But using BUG_ON() is too strong, it means
virt_addr_valid() will BUG when DEBUG_VIRTUAL is enabled.

Instead switch them to warnings, arm64 does the same.

Fixes: 4dd7554a6456 ("powerpc/64: Add VIRTUAL_BUG_ON checks for __va and __pa addresses")
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220406145802.538416-5-mpe@ellerman.id.au
Signed-off-by: Sasha Levin

powerpc: Fix virt_addr_valid() for 64-bit Book3E & 32-bit

2022-04-20T07:19:37+00:00

[ Upstream commit ffa0b64e3be58519ae472ea29a1a1ad681e32f48 ]

mpe: On 64-bit Book3E vmalloc space starts at 0x8000000000000000.

Because of the way __pa() works we have:
  __pa(0x8000000000000000) == 0, and therefore
  virt_to_pfn(0x8000000000000000) == 0, and therefore
  virt_addr_valid(0x8000000000000000) == true

Which is wrong, virt_addr_valid() should be false for vmalloc space.
In fact all vmalloc addresses that alias with a valid PFN will return
true from virt_addr_valid(). That can cause bugs with hardened usercopy
as described below by Kefeng Wang:

  When running ethtool eth0 on 64-bit Book3E, a BUG occurred:

    usercopy: Kernel memory exposure attempt detected from SLUB object not in SLUB page?! (offset 0, size 1048)!
    kernel BUG at mm/usercopy.c:99
    ...
    usercopy_abort+0x64/0xa0 (unreliable)
    __check_heap_object+0x168/0x190
    __check_object_size+0x1a0/0x200
    dev_ethtool+0x2494/0x2b20
    dev_ioctl+0x5d0/0x770
    sock_do_ioctl+0xf0/0x1d0
    sock_ioctl+0x3ec/0x5a0
    __se_sys_ioctl+0xf0/0x160
    system_call_exception+0xfc/0x1f0
    system_call_common+0xf8/0x200

  The code shows below,

    data = vzalloc(array_size(gstrings.len, ETH_GSTRING_LEN));
    copy_to_user(useraddr, data, gstrings.len * ETH_GSTRING_LEN))

  The data is alloced by vmalloc(), virt_addr_valid(ptr) will return true
  on 64-bit Book3E, which leads to the panic.

  As commit 4dd7554a6456 ("powerpc/64: Add VIRTUAL_BUG_ON checks for __va
  and __pa addresses") does, make sure the virt addr above PAGE_OFFSET in
  the virt_addr_valid() for 64-bit, also add upper limit check to make
  sure the virt is below high_memory.

  Meanwhile, for 32-bit PAGE_OFFSET is the virtual address of the start
  of lowmem, high_memory is the upper low virtual address, the check is
  suitable for 32-bit, this will fix the issue mentioned in commit
  602946ec2f90 ("powerpc: Set max_mapnr correctly") too.

On 32-bit there is a similar problem with high memory, that was fixed in
commit 602946ec2f90 ("powerpc: Set max_mapnr correctly"), but that
commit breaks highmem and needs to be reverted.

We can't easily fix __pa(), we have code that relies on its current
behaviour. So for now add extra checks to virt_addr_valid().

For 64-bit Book3S the extra checks are not necessary, the combination of
virt_to_pfn() and pfn_valid() should yield the correct result, but they
are harmless.

Signed-off-by: Kefeng Wang 
Reviewed-by: Christophe Leroy 
[mpe: Add additional change log detail]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220406145802.538416-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin

powerpc: Fix build errors with newer binutils

2022-04-15T12:18:25+00:00

commit 8667d0d64dd1f84fd41b5897fd87fa9113ae05e3 upstream.

Building tinyconfig with gcc (Debian 11.2.0-16) and assembler (Debian
2.37.90.20220207) the following build error shows up:

  {standard input}: Assembler messages:
  {standard input}:1190: Error: unrecognized opcode: `stbcix'
  {standard input}:1433: Error: unrecognized opcode: `lwzcix'
  {standard input}:1453: Error: unrecognized opcode: `stbcix'
  {standard input}:1460: Error: unrecognized opcode: `stwcix'
  {standard input}:1596: Error: unrecognized opcode: `stbcix'
  ...

Rework to add assembler directives [1] around the instruction. Going
through them one by one shows that the changes should be safe.  Like
__get_user_atomic_128_aligned() is only called in p9_hmi_special_emu(),
which according to the name is specific to power9.  And __raw_rm_read*()
are only called in things that are powernv or book3s_hv specific.

[1] https://sourceware.org/binutils/docs/as/PowerPC_002dPseudo.html#PowerPC_002dPseudo

Cc: stable@vger.kernel.org
Co-developed-by: Arnd Bergmann 
Signed-off-by: Arnd Bergmann 
Signed-off-by: Anders Roxell 
Reviewed-by: Segher Boessenkool 
[mpe: Make commit subject more descriptive]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220224162215.3406642-2-anders.roxell@linaro.org
Signed-off-by: Greg Kroah-Hartman