In those hot functions that are called at every interrupt, any saved
cycle is worth it.
interrupt_exit_user_prepare() and interrupt_exit_kernel_prepare() are
called from three places:
- From entry_32.S
- From interrupt_64.S
- From interrupt_exit_user_restart() and interrupt_exit_kernel_restart()
In entry_32.S, there are inambiguously called based on MSR_PR:
interrupt_return:
lwz r4,_MSR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
andi. r0,r4,MSR_PR
beq .Lkernel_interrupt_return
bl interrupt_exit_user_prepare
...
.Lkernel_interrupt_return:
bl interrupt_exit_kernel_prepare
In interrupt_64.S, that's similar:
interrupt_return_\srr\():
ld r4,_MSR(r1)
andi. r0,r4,MSR_PR
beq interrupt_return_\srr\()_kernel
interrupt_return_\srr\()_user: /* make backtraces match the _kernel variant */
addi r3,r1,STACK_FRAME_OVERHEAD
bl interrupt_exit_user_prepare
...
interrupt_return_\srr\()_kernel:
addi r3,r1,STACK_FRAME_OVERHEAD
bl interrupt_exit_kernel_prepare
In interrupt_exit_user_restart() and interrupt_exit_kernel_restart(),
MSR_PR is verified respectively by BUG_ON(!user_mode(regs)) and
BUG_ON(user_mode(regs)) prior to calling interrupt_exit_user_prepare()
and interrupt_exit_kernel_prepare().
The verification in interrupt_exit_user_prepare() and
interrupt_exit_kernel_prepare() are therefore useless and can be removed.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/385ead49ccb66a259b25fee3eebf0bd4094068f3.1629707037.git.christophe.leroy@csgroup.eu
Create an anonymous union for dar and dear regsiters, we can reference
dear to get the effective address when CONFIG_4xx=y or CONFIG_BOOKE=y.
Otherwise, reference dar. This makes code more clear.
Signed-off-by: Xiongwei Song <sxwjean@gmail.com>
[mpe: Reword commit title]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210807010239.416055-4-sxwjean@me.com
Create an anonymous union for dsisr and esr regsiters, we can reference
esr to get the exception detail when CONFIG_4xx=y or CONFIG_BOOKE=y.
Otherwise, reference dsisr. This makes code more clear.
Signed-off-by: Xiongwei Song <sxwjean@gmail.com>
[mpe: Reword commit title]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210807010239.416055-2-sxwjean@me.com
Transactional Memory was removed from the architecture in ISA v3.1. For
threads running in P8/P9 compatibility mode on P10 a synthetic TM
implementation is provided. In this implementation, tbegin. always sets
cr0 eq meaning the abort handler is always called. This is not an issue
as users of TM are expected to have a fallback non transactional way to
make forward progress in the abort handler. The TEXASR indicates if a
transaction failure is due to a synthetic implementation.
Some of the TM self tests need a non-degenerate TM implementation for
their testing to be meaningful so check for a synthetic implementation
and skip the test if so.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210729041317.366612-2-jniethe5@gmail.com
ISA v3.1 removes TM but includes a synthetic implementation for
backwards compatibility. With this implementation, the tests
ptrace-tm-spd-gpr and ptrace-tm-gpr should never be able to make any
forward progress and eventually should be killed by the timeout.
Instead on a P10 running in P9 mode, ptrace_tm_gpr fails like so:
test: ptrace_tm_gpr
tags: git_version:unknown
Starting the child
...
...
GPR[27]: 1 Expected: 2
GPR[28]: 1 Expected: 2
GPR[29]: 1 Expected: 2
GPR[30]: 1 Expected: 2
GPR[31]: 1 Expected: 2
[FAIL] Test FAILED on line 98
failure: ptrace_tm_gpr
selftests: ptrace-tm-gpr [FAIL]
The problem is in the inline assembly of the child. r0 is loaded with a
value in the child's transaction abort handler but this register is not
included in the clobbers list. This means it is possible that this
statement:
cptr[1] = 0;
which is meant to signal the parent to wait may actually use the value
placed into r0 by the inline assembly incorrectly signal the parent to
continue.
By inspection the same problem is present in ptrace-tm-spd-gpr.
Adding r0 to the clobbbers list makes the test fail correctly via a
timeout on a P10 running in P8/P9 compatibility mode.
Suggested-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210729041317.366612-1-jniethe5@gmail.com
Incase of random sampling, there can be scenarios where
Sample Instruction Address Register(SIAR) may not latch
to the sampled instruction and could result in
the value of 0. In these scenarios it is preferred to
return regs->nip. These corner cases are seen in the
previous generation (p9) also.
Patch adds the check for SIAR value along with regs_use_siar
and siar_valid checks so that the function will return
regs->nip incase SIAR is zero.
Patch drops the code under PPMU_P10_DD1 flag check
which handles SIAR 0 case only for Power10 DD1.
Fixes: 2ca13a4cc5 ("powerpc/perf: Use regs->nip when SIAR is zero")
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210818171556.36912-3-kjain@linux.ibm.com
Drop the case of returning 0 as instruction pointer since kernel
never executes at 0 and userspace almost never does either.
Fixes: e6878835ac ("powerpc/perf: Sample only if SIAR-Valid bit is set in P7+")
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210818171556.36912-2-kjain@linux.ibm.com
Minor optimization in the 'perf_instruction_pointer' function code by
making use of stack siar instead of mfspr.
Fixes: 75382aa72f ("powerpc/perf: Move code to select SIAR or pt_regs into perf_read_regs")
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Tested-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210818171556.36912-1-kjain@linux.ibm.com
This register is not architected and not implemented in POWER9 or 10,
it just reads back zeroes for compatibility.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Link: https://lore.kernel.org/r/20210811160134.904987-11-npiggin@gmail.com
After the L1 saves its PMU SPRs but before loading the L2's PMU SPRs,
switch the pmcregs_in_use field in the L1 lppaca to the value advertised
by the L2 in its VPA. On the way out of the L2, set it back after saving
the L2 PMU registers (if they were in-use).
This transfers the PMU liveness indication between the L1 and L2 at the
points where the registers are not live.
This fixes the nested HV bug for which a workaround was added to the L0
HV by commit 63279eeb7f ("KVM: PPC: Book3S HV: Always save guest pmu
for guest capable of nesting"), which explains the problem in detail.
That workaround is no longer required for guests that include this bug
fix.
Fixes: 360cae3137 ("KVM: PPC: Book3S HV: Nested guest entry via hypercall")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Link: https://lore.kernel.org/r/20210811160134.904987-10-npiggin@gmail.com
vcpu is already anargument so vcpu->arch.trap can be used directly.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-9-npiggin@gmail.com
If the nested hypervisor has no access to a facility because it has
been disabled by the host, it should also not be able to see the
Hypervisor Facility Unavailable that arises from one of its guests
trying to access the facility.
This patch turns a HFU that happened in L2 into a Hypervisor Emulation
Assistance interrupt and forwards it to L1 for handling. The ones that
happened because L1 explicitly disabled the facility for L2 are still
let through, along with the corresponding Cause bits in the HFSCR.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
[np: move handling into kvmppc_handle_nested_exit]
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-8-npiggin@gmail.com
When the L0 runs a nested L2, there are several permutations of HFSCR
that can be relevant. The HFSCR that the L1 vcpu L1 requested, the
HFSCR that the L1 vcpu may use, and the HFSCR that is actually being
used to run the L2.
The L1 requested HFSCR is not accessible outside the nested hcall
handler, so copy that into a new kvm_nested_guest.hfscr field.
The permitted HFSCR is taken from the HFSCR that the L1 runs with,
which is also not accessible while the hcall is being made. Move
this into a new kvm_vcpu_arch.hfscr_permitted field.
These will be used by the next patch to improve facility handling
for nested guests, and later by facility demand faulting patches.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-7-npiggin@gmail.com
As one of the arguments of the H_ENTER_NESTED hypercall, the nested
hypervisor (L1) prepares a structure containing the values of various
hypervisor-privileged registers with which it wants the nested guest
(L2) to run. Since the nested HV runs in supervisor mode it needs the
host to write to these registers.
To stop a nested HV manipulating this mechanism and using a nested
guest as a proxy to access a facility that has been made unavailable
to it, we have a routine that sanitises the values of the HV registers
before copying them into the nested guest's vcpu struct.
However, when coming out of the guest the values are copied as they
were back into L1 memory, which means that any sanitisation we did
during guest entry will be exposed to L1 after H_ENTER_NESTED returns.
This patch alters this sanitisation to have effect on the vcpu->arch
registers directly before entering and after exiting the guest,
leaving the structure that is copied back into L1 unchanged (except
when we really want L1 to access the value, e.g the Cause bits of
HFSCR).
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Link: https://lore.kernel.org/r/20210811160134.904987-6-npiggin@gmail.com
Have the TM softpatch emulation code set up the HFAC interrupt and
return -1 in case an instruction was executed with HFSCR bits clear,
and have the interrupt exit handler fall through to the HFAC handler.
When the L0 is running a nested guest, this ensures the HFAC interrupt
is correctly passed up to the L1.
The "direct guest" exit handler will turn these into PROGILL program
interrupts so functionality in practice will be unchanged. But it's
possible an L1 would want to handle these in a different way.
Also rearrange the FAC interrupt emulation code to match the HFAC format
while here (mainly, adding the FSCR_INTR_CAUSE mask).
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-5-npiggin@gmail.com
The softpatch interrupt sets HSRR0 to the faulting instruction +4, so
it should subtract 4 for the faulting instruction address in the case
it is a TM softpatch interrupt (the instruction was not executed) and
it was not emulated.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-4-npiggin@gmail.com
It is possible to create a VCPU without setting the MSR before running
it, which results in a warning in kvmhv_vcpu_entry_p9() that MSR_ME is
not set. This is pretty harmless because the MSR_ME bit is added to
HSRR1 before HRFID to guest, and a normal qemu guest doesn't hit it.
Initialise the vcpu MSR with MSR_ME set.
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-2-npiggin@gmail.com
Today we have:
#ifdef __powerpc64__
#define user_mode(regs) ((((regs)->msr) >> MSR_PR_LG) & 0x1)
#else
#define user_mode(regs) (((regs)->msr & MSR_PR) != 0)
#endif
With ppc64_defconfig, we get:
if (!user_mode(regs))
14b4: e9 3e 01 08 ld r9,264(r30)
14b8: 71 29 40 00 andi. r9,r9,16384
14bc: 41 82 07 a4 beq 1c60 <.emulate_instruction+0x7d0>
If taking the ppc32 definition of user_mode(), the exact same code
is generated for ppc64_defconfig.
So, only keep one version of user_mode(), preferably the one not
using MSR_PR_LG which should be kept internal to reg.h.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/000a28c51808bbd802b505af42d2cb316c2be7d3.1629216000.git.christophe.leroy@csgroup.eu
Copied from commit 89bbe4c798 ("powerpc/64: indirect function call
use bctrl rather than blrl in ret_from_kernel_thread")
blrl is not recommended to use as an indirect function call, as it may
corrupt the link stack predictor.
This is not a performance critical path but this should be fixed for
consistency.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/91b1d242525307ceceec7ef6e832bfbacdd4501b.1629436472.git.christophe.leroy@csgroup.eu
The book3s_64_mmu_radix.o object is not part of the KVM builtins and
all the callers of the exported symbols are in the same kvm-hv.ko
module so we should not need to export any symbols.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210805212616.2641017-4-farosas@linux.ibm.com
Both paths into __kvmhv_copy_tofrom_guest_radix ensure that we arrive
with an effective address that is smaller than our total addressable
space and addresses quadrant 0.
- The H_COPY_TOFROM_GUEST hypercall path rejects the call with
H_PARAMETER if the effective address has any of the twelve most
significant bits set.
- The kvmhv_copy_tofrom_guest_radix path clears the top twelve bits
before calling the internal function.
Although the callers make sure that the effective address is sane, any
future use of the function is exposed to a programming error, so add a
sanity check.
Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210805212616.2641017-3-farosas@linux.ibm.com
The __kvmhv_copy_tofrom_guest_radix function was introduced along with
nested HV guest support. It uses the platform's Radix MMU quadrants to
provide a nested hypervisor with fast access to its nested guests
memory (H_COPY_TOFROM_GUEST hypercall). It has also since been added
as a fast path for the kvmppc_ld/st routines which are used during
instruction emulation.
The commit def0bfdbd6 ("powerpc: use probe_user_read() and
probe_user_write()") changed the low level copy function from
raw_copy_from_user to probe_user_read, which adds a check to
access_ok. In powerpc that is:
static inline bool __access_ok(unsigned long addr, unsigned long size)
{
return addr < TASK_SIZE_MAX && size <= TASK_SIZE_MAX - addr;
}
and TASK_SIZE_MAX is 0x0010000000000000UL for 64-bit, which means that
setting the two MSBs of the effective address (which correspond to the
quadrant) now cause access_ok to reject the access.
This was not caught earlier because the most common code path via
kvmppc_ld/st contains a fallback (kvm_read_guest) that is likely to
succeed for L1 guests. For nested guests there is no fallback.
Another issue is that probe_user_read (now __copy_from_user_nofault)
does not return the number of bytes not copied in case of failure, so
the destination memory is not being cleared anymore in
kvmhv_copy_from_guest_radix:
ret = kvmhv_copy_tofrom_guest_radix(vcpu, eaddr, to, NULL, n);
if (ret > 0) <-- always false!
memset(to + (n - ret), 0, ret);
This patch fixes both issues by skipping access_ok and open-coding the
low level __copy_to/from_user_inatomic.
Fixes: def0bfdbd6 ("powerpc: use probe_user_read() and probe_user_write()")
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210805212616.2641017-2-farosas@linux.ibm.com
This fixes a compile error with W=1.
arch/powerpc/kernel/prom.c: In function ‘early_reserve_mem’:
arch/powerpc/kernel/prom.c:625:10: error: variable ‘reserve_map’ set but not used [-Werror=unused-but-set-variable]
__be64 *reserve_map;
^~~~~~~~~~~
cc1: all warnings being treated as errors
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210823090039.166120-2-clg@kaod.org
__NR__exit is nowhere used. On most architectures it was removed by
commit 135ab6ec8f ("[PATCH] remove remaining errno and
__KERNEL_SYSCALLS__ references") but not on powerpc.
powerpc removed __KERNEL_SYSCALLS__ in commit 3db03b4afb ("[PATCH]
rename the provided execve functions to kernel_execve"), but __NR__exit
was left over.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/6457eb4f327313323ed1f70e540bbb4ddc9178fa.1629701106.git.christophe.leroy@csgroup.eu
H_GetPerformanceCounterInfo (0xF080) hcall returns the counter data in
the result buffer. Result buffer has specific format defined in the PAPR
specification. One of the fields is counter offset and width of the
counter data returned.
Counter data are returned in a unsigned char array in big endian byte
order. To get the final counter data, the values must be left shifted
byte at a time. But commit 220a0c609a ("powerpc/perf: Add support for
the hv gpci (get performance counter info) interface") made the shifting
bitwise and also assumed little endian order. Because of that, hcall
counters values are reported incorrectly.
In particular this can lead to counters go backwards which messes up the
counter prev vs now calculation and leads to huge counter value
reporting:
#: perf stat -e hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
-C 0 -I 1000
time counts unit events
1.000078854 18,446,744,073,709,535,232 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
2.000213293 0 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
3.000320107 0 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
4.000428392 0 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
5.000537864 0 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
6.000649087 0 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
7.000760312 0 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
8.000865218 16,448 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
9.000978985 18,446,744,073,709,535,232 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
10.001088891 16,384 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
11.001201435 0 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
12.001307937 18,446,744,073,709,535,232 hv_gpci/system_tlbie_count_and_time_tlbie_instructions_issued/
Fix the shifting logic to correct match the format, ie. read bytes in
big endian order.
Fixes: e4f226b158 ("powerpc/perf/hv-gpci: Increase request buffer size")
Cc: stable@vger.kernel.org # v4.6+
Reported-by: Nageswara R Sastry<rnsastry@linux.ibm.com>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Tested-by: Nageswara R Sastry<rnsastry@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210813082158.429023-1-kjain@linux.ibm.com
This patch prevents the following sparse warning.
arch/powerpc/kernel/tau_6xx.c:199:1: sparse: sparse: symbol 'tau_work'
was not declared. Should it be static?
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/44ab381741916a51e783c4a50d0b186abdd8f280.1629334014.git.fthain@linux-m68k.org
Commit a278e7ea60 ("powerpc: Fix compile issue with force DAWR")
selects the non-existing config PPC_DAWR_FORCE_ENABLE for config
KVM_BOOK3S_64_HANDLER. As this commit also introduces a config PPC_DAWR
and this config PPC_DAWR is selected with PPC if PPC64, there is no
need for any further select in the KVM_BOOK3S_64_HANDLER.
Remove an obsolete and unneeded select in config KVM_BOOK3S_64_HANDLER.
The issue was identified with ./scripts/checkkconfigsymbols.py.
Fixes: a278e7ea60 ("powerpc: Fix compile issue with force DAWR")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210819113954.17515-2-lukas.bulwahn@gmail.com
interrupt.c: asm/interrupt.h has been included at line 12, so remove the
duplicate one at line 10.
time.c: linux/sched/clock.h has been included at line 33,so remove the
duplicate one at line 56 and move sched/cputime.h under sched including
segament.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210323062916.295346-1-wanjiabing@vivo.com
Regenerate atop v5.14-rc6 by doing a make savedefconfig.
The changes a re-ordering except for the following (which are still set
indirectly):
- CONFIG_DEBUG_KERNEL=y selected by EXPERT
- CONFIG_PPC_EARLY_DEBUG_CPM_ADDR=0xff002008 which is the default
setting
Signed-off-by: Joel Stanley <joel@jms.id.au>
Acked-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210817045407.2445664-4-joel@jms.id.au
