commit fe663df7825811358531dc2e8a52d9eaa5e3515e 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}:2088: Error: unrecognized opcode: `ptesync'
make[3]: *** [/builds/linux/scripts/Makefile.build:287: arch/powerpc/lib/sstep.o] Error 1
Add the 'ifdef CONFIG_PPC64' around the 'ptesync' in function
'emulate_update_regs()' to like it is in 'analyse_instr()'. Since it looks like
it got dropped inadvertently by commit 3cdfcbfd32 ("powerpc: Change
analyse_instr so it doesn't modify *regs").
A key detail is that analyse_instr() will never recognise lwsync or
ptesync on 32-bit (because of the existing ifdef), and as a result
emulate_update_regs() should never be called with an op specifying
either of those on 32-bit. So removing them from emulate_update_regs()
should be a nop in terms of runtime behaviour.
Fixes: 3cdfcbfd32 ("powerpc: Change analyse_instr so it doesn't modify *regs")
Cc: stable@vger.kernel.org # v4.14+
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
[mpe: Add last paragraph of change log mentioning analyse_instr() details]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220211005113.1361436-1-anders.roxell@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3f5f766d5f7f95a69a630da3544a1a0cee1cdddf ]
Johan reported the below crash with test_bpf on ppc64 e5500:
test_bpf: #296 ALU_END_FROM_LE 64: 0x0123456789abcdef -> 0x67452301 jited:1
Oops: Exception in kernel mode, sig: 4 [#1]
BE PAGE_SIZE=4K SMP NR_CPUS=24 QEMU e500
Modules linked in: test_bpf(+)
CPU: 0 PID: 76 Comm: insmod Not tainted 5.14.0-03771-g98c2059e008a-dirty #1
NIP: 8000000000061c3c LR: 80000000006dea64 CTR: 8000000000061c18
REGS: c0000000032d3420 TRAP: 0700 Not tainted (5.14.0-03771-g98c2059e008a-dirty)
MSR: 0000000080089000 <EE,ME> CR: 88002822 XER: 20000000 IRQMASK: 0
<...>
NIP [8000000000061c3c] 0x8000000000061c3c
LR [80000000006dea64] .__run_one+0x104/0x17c [test_bpf]
Call Trace:
.__run_one+0x60/0x17c [test_bpf] (unreliable)
.test_bpf_init+0x6a8/0xdc8 [test_bpf]
.do_one_initcall+0x6c/0x28c
.do_init_module+0x68/0x28c
.load_module+0x2460/0x2abc
.__do_sys_init_module+0x120/0x18c
.system_call_exception+0x110/0x1b8
system_call_common+0xf0/0x210
--- interrupt: c00 at 0x101d0acc
<...>
---[ end trace 47b2bf19090bb3d0 ]---
Illegal instruction
The illegal instruction turned out to be 'ldbrx' emitted for
BPF_FROM_[L|B]E, which was only introduced in ISA v2.06. Guard use of
the same and implement an alternative approach for older processors.
Fixes: 156d0e290e ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF")
Reported-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d1e51c6fdf572062cf3009a751c3406bda01b832.1641468127.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit bba496656a73fc1d1330b49c7f82843836e9feb1 upstream.
Boot fails with GCC latent entropy plugin enabled.
This is due to early boot functions trying to access 'latent_entropy'
global data while the kernel is not relocated at its final
destination yet.
As there is no way to tell GCC to use PTRRELOC() to access it,
disable latent entropy plugin in early_32.o and feature-fixups.o and
code-patching.o
Fixes: 38addce8b6 ("gcc-plugins: Add latent_entropy plugin")
Cc: stable@vger.kernel.org # v4.9+
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215217
Link: https://lore.kernel.org/r/2bac55483b8daf5b1caa163a45fa5f9cdbe18be4.1640178426.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d37823c3528e5e0705fc7746bcbc2afffb619259 upstream.
It has been reported some configuration where the kernel doesn't
boot with KASAN enabled.
This is due to wrong BAT allocation for the KASAN area:
---[ Data Block Address Translation ]---
0: 0xc0000000-0xcfffffff 0x00000000 256M Kernel rw m
1: 0xd0000000-0xdfffffff 0x10000000 256M Kernel rw m
2: 0xe0000000-0xefffffff 0x20000000 256M Kernel rw m
3: 0xf8000000-0xf9ffffff 0x2a000000 32M Kernel rw m
4: 0xfa000000-0xfdffffff 0x2c000000 64M Kernel rw m
A BAT must have both virtual and physical addresses alignment matching
the size of the BAT. This is not the case for BAT 4 above.
Fix kasan_init_region() by using block_size() function that is in
book3s32/mmu.c. To be able to reuse it here, make it non static and
change its name to bat_block_size() in order to avoid name conflict
with block_size() defined in <linux/blkdev.h>
Also reuse find_free_bat() to avoid an error message from setbat()
when no BAT is available.
And allocate memory outside of linear memory mapping to avoid
wasting that precious space.
With this change we get correct alignment for BATs and KASAN shadow
memory is allocated outside the linear memory space.
---[ Data Block Address Translation ]---
0: 0xc0000000-0xcfffffff 0x00000000 256M Kernel rw
1: 0xd0000000-0xdfffffff 0x10000000 256M Kernel rw
2: 0xe0000000-0xefffffff 0x20000000 256M Kernel rw
3: 0xf8000000-0xfbffffff 0x7c000000 64M Kernel rw
4: 0xfc000000-0xfdffffff 0x7a000000 32M Kernel rw
Fixes: 7974c47326 ("powerpc/32s: Implement dedicated kasan_init_region()")
Cc: stable@vger.kernel.org
Reported-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7a50ef902494d1325227d47d33dada01e52e5518.1641818726.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 37eb7ca91b692e8e49e7dd50158349a6c8fb5b09 upstream.
Today we have the following IBATs allocated:
---[ Instruction Block Address Translation ]---
0: 0xc0000000-0xc03fffff 0x00000000 4M Kernel x m
1: 0xc0400000-0xc05fffff 0x00400000 2M Kernel x m
2: 0xc0600000-0xc06fffff 0x00600000 1M Kernel x m
3: 0xc0700000-0xc077ffff 0x00700000 512K Kernel x m
4: 0xc0780000-0xc079ffff 0x00780000 128K Kernel x m
5: 0xc07a0000-0xc07bffff 0x007a0000 128K Kernel x m
6: -
7: -
The two 128K should be a single 256K instead.
When _etext is not aligned to 128Kbytes, the system will allocate
all necessary BATs to the lower 128Kbytes boundary, then allocate
an additional 128Kbytes BAT for the remaining block.
Instead, align the top to 128Kbytes so that the function directly
allocates a 256Kbytes last block:
---[ Instruction Block Address Translation ]---
0: 0xc0000000-0xc03fffff 0x00000000 4M Kernel x m
1: 0xc0400000-0xc05fffff 0x00400000 2M Kernel x m
2: 0xc0600000-0xc06fffff 0x00600000 1M Kernel x m
3: 0xc0700000-0xc077ffff 0x00700000 512K Kernel x m
4: 0xc0780000-0xc07bffff 0x00780000 256K Kernel x m
5: -
6: -
7: -
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ab58b296832b0ec650e2203200e060adbcb2677d.1637930421.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0d375d610fa96524e2ee2b46830a46a7bfa92a9f upstream.
This block is used in (at least) T1024 and T1040, including their
variants like T1023 etc.
Fixes: d55ad2967d ("powerpc/mpc85xx: Create dts components for the FSL QorIQ DPAA FMan")
Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e89257e28e844f5d1d39081bb901d9f1183a7705 upstream.
Clang warns:
arch/powerpc/platforms/cell/pervasive.c:81:2: error: unannotated fall-through between switch labels
case SRR1_WAKEEE:
^
arch/powerpc/platforms/cell/pervasive.c:81:2: note: insert 'break;' to avoid fall-through
case SRR1_WAKEEE:
^
break;
1 error generated.
Clang is more pedantic than GCC, which does not warn when failing
through to a case that is just break or return. Clang's version is more
in line with the kernel's own stance in deprecated.rst. Add athe missing
break to silence the warning.
Fixes: 6e83985b0f ("powerpc/cbe: Do not process external or decremeter interrupts from sreset")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211207110228.698956-1-anders.roxell@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 467ba14e1660b52a2f9338b484704c461bd23019 upstream.
pmd_huge() is defined to false when HUGETLB_PAGE is not configured, but
the vmap code still installs huge PMDs. This leads to false bad PMD
errors when vunmapping because it is not seen as a huge PTE, and the bad
PMD check catches it. The end result may not be much more serious than
some bad pmd warning messages, because the pmd_none_or_clear_bad() does
what we wanted and clears the huge PTE anyway.
Fix this by checking pmd_is_leaf(), which checks for a PTE regardless of
config options. The whole huge/large/leaf stuff is a tangled mess but
that's kernel-wide and not something we can improve much in arch/powerpc
code.
pmd_page(), pud_page(), etc., called by vmalloc_to_page() on huge vmaps
can similarly trigger a false VM_BUG_ON when CONFIG_HUGETLB_PAGE=n, so
those checks are adjusted. The checks were added by commit d6eacedd1f
("powerpc/book3s: Use config independent helpers for page table walk"),
while implementing a similar fix for other page table walking functions.
Fixes: d909f9109c ("powerpc/64s/radix: Enable HAVE_ARCH_HUGE_VMAP")
Cc: stable@vger.kernel.org # v5.3+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211216103342.609192-1-npiggin@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 06e629c25daa519be620a8c17359ae8fc7a2e903 ]
In panic path, fadump is triggered via a panic notifier function.
Before calling panic notifier functions, smp_send_stop() gets called,
which stops all CPUs except the panic'ing CPU. Commit 8389b37dff
("powerpc: stop_this_cpu: remove the cpu from the online map.") and
again commit bab26238bbd4 ("powerpc: Offline CPU in stop_this_cpu()")
started marking CPUs as offline while stopping them. So, if a kernel
has either of the above commits, vmcore captured with fadump via panic
path would not process register data for all CPUs except the panic'ing
CPU. Sample output of crash-utility with such vmcore:
# crash vmlinux vmcore
...
KERNEL: vmlinux
DUMPFILE: vmcore [PARTIAL DUMP]
CPUS: 1
DATE: Wed Nov 10 09:56:34 EST 2021
UPTIME: 00:00:42
LOAD AVERAGE: 2.27, 0.69, 0.24
TASKS: 183
NODENAME: XXXXXXXXX
RELEASE: 5.15.0+
VERSION: #974 SMP Wed Nov 10 04:18:19 CST 2021
MACHINE: ppc64le (2500 Mhz)
MEMORY: 8 GB
PANIC: "Kernel panic - not syncing: sysrq triggered crash"
PID: 3394
COMMAND: "bash"
TASK: c0000000150a5f80 [THREAD_INFO: c0000000150a5f80]
CPU: 1
STATE: TASK_RUNNING (PANIC)
crash> p -x __cpu_online_mask
__cpu_online_mask = $1 = {
bits = {0x2, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}
}
crash>
crash>
crash> p -x __cpu_active_mask
__cpu_active_mask = $2 = {
bits = {0xff, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}
}
crash>
While this has been the case since fadump was introduced, the issue
was not identified for two probable reasons:
- In general, the bulk of the vmcores analyzed were from crash
due to exception.
- The above did change since commit 8341f2f222 ("sysrq: Use
panic() to force a crash") started using panic() instead of
deferencing NULL pointer to force a kernel crash. But then
commit de6e5d3841 ("powerpc: smp_send_stop do not offline
stopped CPUs") stopped marking CPUs as offline till kernel
commit bab26238bbd4 ("powerpc: Offline CPU in stop_this_cpu()")
reverted that change.
To ensure post processing register data of all other CPUs happens
as intended, let panic() function take the crash friendly path (read
crash_smp_send_stop()) with the help of crash_kexec_post_notifiers
option. Also, as register data for all CPUs is captured by f/w, skip
IPI callbacks here for fadump, to avoid any complications in finding
the right backtraces.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211207103719.91117-2-hbathini@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 219572d2fc4135b5ce65c735d881787d48b10e71 ]
Kdump can be triggered after panic_notifers since commit f06e5153f4
("kernel/panic.c: add "crash_kexec_post_notifiers" option for kdump
after panic_notifers") introduced crash_kexec_post_notifiers option.
But using this option would mean smp_send_stop(), that marks all other
CPUs as offline, gets called before kdump is triggered. As a result,
kdump routines fail to save other CPUs' registers. To fix this, kdump
friendly crash_smp_send_stop() function was introduced with kernel
commit 0ee59413c9 ("x86/panic: replace smp_send_stop() with kdump
friendly version in panic path"). Override this kdump friendly weak
function to handle crash_kexec_post_notifiers option appropriately
on powerpc.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
[Fixed signature of crash_stop_this_cpu() - reported by lkp@intel.com]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211207103719.91117-1-hbathini@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 06e7cbc29e97b4713b4ea6def04ae8501a7d1a59 ]
As reported by Carlo, 16Mbytes is not enough with modern kernels
that tend to be a bit big, so map another 16M page at boot.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/89b5f974a7fa5011206682cd092e2c905530ff46.1632755552.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 792020907b11c6f9246c21977cab3bad985ae4b6 ]
H_COPY_TOFROM_GUEST is an hcall for an upper level VM to access its nested
VMs memory. The userspace can trigger WARN_ON_ONCE(!(gfp & __GFP_NOWARN))
in __alloc_pages() by constructing a tiny VM which only does
H_COPY_TOFROM_GUEST with a too big GPR9 (number of bytes to copy).
This silences the warning by adding __GFP_NOWARN.
Spotted by syzkaller.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210901084550.1658699-1-aik@ozlabs.ru
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 511d25d6b789fffcb20a3eb71899cf974a31bd9d ]
The userspace can trigger "vmalloc size %lu allocation failure: exceeds
total pages" via the KVM_SET_USER_MEMORY_REGION ioctl.
This silences the warning by checking the limit before calling vzalloc()
and returns ENOMEM if failed.
This does not call underlying valloc helpers as __vmalloc_node() is only
exported when CONFIG_TEST_VMALLOC_MODULE and __vmalloc_node_range() is
not exported at all.
Spotted by syzkaller.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[mpe: Use 'size' for the variable rather than 'cb']
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210901084512.1658628-1-aik@ozlabs.ru
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a4ac0d249a5db80e79d573db9e4ad29354b643a8 ]
setup_profiling_timer() is only needed when CONFIG_PROFILING is enabled.
Fixes the following W=1 warning when CONFIG_PROFILING=n:
linux/arch/powerpc/kernel/smp.c:1638:5: error: no previous prototype for ‘setup_profiling_timer’
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211124093254.1054750-5-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5dad4ba68a2483fc80d70b9dc90bbe16e1f27263 ]
It is possible for all CPUs to miss the pending cpumask becoming clear,
and then nobody resetting it, which will cause the lockup detector to
stop working. It will eventually expire, but watchdog_smp_panic will
avoid doing anything if the pending mask is clear and it will never be
reset.
Order the cpumask clear vs the subsequent test to close this race.
Add an extra check for an empty pending mask when the watchdog fires and
finds its bit still clear, to try to catch any other possible races or
bugs here and keep the watchdog working. The extra test in
arch_touch_nmi_watchdog is required to prevent the new warning from
firing off.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Debugged-by: Laurent Dufour <ldufour@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211110025056.2084347-2-npiggin@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a1d2b210ffa52d60acabbf7b6af3ef7e1e69cda0 ]
for_each_node_by_type performs an of_node_get on each iteration, so
a break out of the loop requires an of_node_put.
A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):
// <smpl>
@@
local idexpression n;
expression e;
@@
for_each_node_by_type(n,...) {
...
(
of_node_put(n);
|
e = n
|
+ of_node_put(n);
? break;
)
...
}
... when != n
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1448051604-25256-6-git-send-email-Julia.Lawall@lip6.fr
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a841fd009e51c8c0a8f07c942e9ab6bb48da8858 ]
for_each_node_by_name performs an of_node_get on each iteration, so
a break out of the loop requires an of_node_put.
A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):
// <smpl>
@@
expression e,e1;
local idexpression n;
@@
for_each_node_by_name(n, e1) {
... when != of_node_put(n)
when != e = n
(
return n;
|
+ of_node_put(n);
? return ...;
)
...
}
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1448051604-25256-7-git-send-email-Julia.Lawall@lip6.fr
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7d405a939ca960162eb30c1475759cb2fdf38f8c ]
for_each_compatible_node performs an of_node_get on each iteration, so
a break out of the loop requires an of_node_put.
A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):
// <smpl>
@@
local idexpression n;
expression e;
@@
for_each_compatible_node(n,...) {
...
(
of_node_put(n);
|
e = n
|
+ of_node_put(n);
? break;
)
...
}
... when != n
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1448051604-25256-4-git-send-email-Julia.Lawall@lip6.fr
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f6e82647ff71d427d4148964b71f239fba9d7937 ]
for_each_compatible_node performs an of_node_get on each iteration, so
a break out of the loop requires an of_node_put.
A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):
// <smpl>
@@
expression e;
local idexpression n;
@@
@@
local idexpression n;
expression e;
@@
for_each_compatible_node(n,...) {
...
(
of_node_put(n);
|
e = n
|
+ of_node_put(n);
? break;
)
...
}
... when != n
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1448051604-25256-2-git-send-email-Julia.Lawall@lip6.fr
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b149d5d45ac9171ed699a256f026c8ebef901112 ]
Commit df1f679d19ed ("powerpc/powermac: Add missing
lockdep_register_key()") fixed a problem that was causing a WARNING.
There are two other places in the same file with the same problem
originating from commit 9e607f7274 ("i2c_powermac: shut up lockdep
warning").
Add missing lockdep_register_key()
Fixes: 9e607f7274 ("i2c_powermac: shut up lockdep warning")
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Depends-on: df1f679d19ed ("powerpc/powermac: Add missing lockdep_register_key()")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200055
Link: https://lore.kernel.org/r/2c7e421874e21b2fb87813d768cf662f630c2ad4.1638984999.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2c9ac51b850d84ee496b0a5d832ce66d411ae552 ]
Running perf fuzzer showed below in dmesg logs:
"Can't find PMC that caused IRQ"
This means a PMU exception happened, but none of the PMC's (Performance
Monitor Counter) were found to be overflown. There are some corner cases
that clears the PMCs after PMI gets masked. In such cases, the perf
interrupt handler will not find the active PMC values that had caused
the overflow and thus leads to this message while replaying.
Case 1: PMU Interrupt happens during replay of other interrupts and
counter values gets cleared by PMU callbacks before replay:
During replay of interrupts like timer, __do_irq() and doorbell
exception, we conditionally enable interrupts via may_hard_irq_enable().
This could potentially create a window to generate a PMI. Since irq soft
mask is set to ALL_DISABLED, the PMI will get masked here. We could get
IPIs run before perf interrupt is replayed and the PMU events could
be deleted or stopped. This will change the PMU SPR values and resets
the counters. Snippet of ftrace log showing PMU callbacks invoked in
__do_irq():
<idle>-0 [051] dns. 132025441306354: __do_irq <-call_do_irq
<idle>-0 [051] dns. 132025441306430: irq_enter <-__do_irq
<idle>-0 [051] dns. 132025441306503: irq_enter_rcu <-__do_irq
<idle>-0 [051] dnH. 132025441306599: xive_get_irq <-__do_irq
<<>>
<idle>-0 [051] dnH. 132025441307770: generic_smp_call_function_single_interrupt <-smp_ipi_demux_relaxed
<idle>-0 [051] dnH. 132025441307839: flush_smp_call_function_queue <-smp_ipi_demux_relaxed
<idle>-0 [051] dnH. 132025441308057: _raw_spin_lock <-event_function
<idle>-0 [051] dnH. 132025441308206: power_pmu_disable <-perf_pmu_disable
<idle>-0 [051] dnH. 132025441308337: power_pmu_del <-event_sched_out
<idle>-0 [051] dnH. 132025441308407: power_pmu_read <-power_pmu_del
<idle>-0 [051] dnH. 132025441308477: read_pmc <-power_pmu_read
<idle>-0 [051] dnH. 132025441308590: isa207_disable_pmc <-power_pmu_del
<idle>-0 [051] dnH. 132025441308663: write_pmc <-power_pmu_del
<idle>-0 [051] dnH. 132025441308787: power_pmu_event_idx <-perf_event_update_userpage
<idle>-0 [051] dnH. 132025441308859: rcu_read_unlock_strict <-perf_event_update_userpage
<idle>-0 [051] dnH. 132025441308975: power_pmu_enable <-perf_pmu_enable
<<>>
<idle>-0 [051] dnH. 132025441311108: irq_exit <-__do_irq
<idle>-0 [051] dns. 132025441311319: performance_monitor_exception <-replay_soft_interrupts
Case 2: PMI's masked during local_* operations, example local_add(). If
the local_add() operation happens within a local_irq_save(), replay of
PMI will be during local_irq_restore(). Similar to case 1, this could
also create a window before replay where PMU events gets deleted or
stopped.
Fix it by updating the PMU callback function power_pmu_disable() to
check for pending perf interrupt. If there is an overflown PMC and
pending perf interrupt indicated in paca, clear the PMI bit in paca to
drop that sample. Clearing of PMI bit is done in power_pmu_disable()
since disable is invoked before any event gets deleted/stopped. With
this fix, if there are more than one event running in the PMU, there is
a chance that we clear the PMI bit for the event which is not getting
deleted/stopped. The other events may still remain active. Hence to make
sure we don't drop valid sample in such cases, another check is added in
power_pmu_enable. This checks if there is an overflown PMC found among
the active events and if so enable back the PMI bit. Two new helper
functions are introduced to clear/set the PMI, ie
clear_pmi_irq_pending() and set_pmi_irq_pending(). Helper function
pmi_irq_pending() is introduced to give a warning if there is pending
PMI bit in paca, but no PMC is overflown.
Also there are corner cases which result in performance monitor
interrupts being triggered during power_pmu_disable(). This happens
since PMXE bit is not cleared along with disabling of other MMCR0 bits
in the pmu_disable. Such PMI's could leave the PMU running and could
trigger PMI again which will set MMCR0 PMAO bit. This could lead to
spurious interrupts in some corner cases. Example, a timer after
power_pmu_del() which will re-enable interrupts and triggers a PMI again
since PMAO bit is still set. But fails to find valid overflow since PMC
was cleared in power_pmu_del(). Fix that by disabling PMXE along with
disabling of other MMCR0 bits in power_pmu_disable().
We can't just replay PMI any time. Hence this approach is preferred
rather than replaying PMI before resetting overflown PMC. Patch also
documents core-book3s on a race condition which can trigger these PMC
messages during idle path in PowerNV.
Fixes: f442d00480 ("powerpc/64s: Add support to mask perf interrupts and replay them")
Reported-by: Nageswara R Sastry <nasastry@in.ibm.com>
Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Suggested-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Make pmi_irq_pending() return bool, reflow/reword some comments]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1626846509-1350-2-git-send-email-atrajeev@linux.vnet.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 156b5371a9c2482a9ad23ec82d1a4f89a3ab430d ]
This is required in order to allow more significant differences between
NMI type interrupt handlers and regular asynchronous handlers.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210130130852.2952424-20-npiggin@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 91668ab7db4bcfae332e561df1de2401f3f18553 ]
PowerISA v3.1 introduces new control bit (PMCCEXT) for restricting
access to group B PMU registers in problem state when
MMCR0 PMCC=0b00. In problem state and when MMCR0 PMCC=0b00,
setting the Monitor Mode Control Register bit 54 (MMCR0 PMCCEXT),
will restrict read permission on Group B Performance Monitor
Registers (SIER, SIAR, SDAR and MMCR1). When this bit is set to zero,
group B registers will be readable. In other platforms (like power9),
the older behaviour is retained where group B PMU SPRs are readable.
Patch adds support for MMCR0 PMCCEXT bit in power10 by enabling
this bit during boot and during the PMU event enable/disable callback
functions.
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1606409684-1589-8-git-send-email-atrajeev@linux.vnet.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 344fbab991a568dc33ad90711b489d870e18d26d ]
The only thing keeping the cpu_setup() and cpu_restore() functions
used in the cputable entries for Power7, Power8, Power9 and Power10 in
assembly was cpu_restore() being called before there was a stack in
generic_secondary_smp_init(). Commit ("powerpc/64: Set up a kernel
stack for secondaries before cpu_restore()") means that it is now
possible to use C.
Rewrite the functions in C so they are a little bit easier to read.
This is not changing their functionality.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Tweak copyright and authorship notes]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201014072837.24539-2-jniethe5@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 869fb7e5aecbc163003f93f36dcc26d0554319f6 ]
prom_getprop() can return PROM_ERROR. Binary operator can not identify
it.
Fixes: 94d2dde738 ("[POWERPC] Efika: prune fixups and make them more carefull")
Signed-off-by: Peiwei Hu <jlu.hpw@foxmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/tencent_BA28CC6897B7C95A92EB8C580B5D18589105@qq.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 65c7d070850e109a8a75a431f5a7f6eb4c007b77 upstream.
This allows the hypervisor / firmware to describe these workarounds to
the guest.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210503130243.891868-2-npiggin@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2d33f5504490a9d90924476dbccd4a5349ee1ad0 ]
This reverts commit 54fc3c681d
which does not allow 1:1 mapping even for the system RAM which
is usually possible.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211108040320.3857636-2-aik@ozlabs.ru
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 5bb60ea611db1e04814426ed4bd1c95d1487678e upstream.
Since the commit c118c7303a ("powerpc/32: Fix vmap stack - Do not
activate MMU before reading task struct") a vmap stack overflow
results in a hard lockup. This is because emergency_ctx is still
addressed with its virtual address allthough data MMU is not active
anymore at that time.
Fix it by using a physical address instead.
Fixes: c118c7303a ("powerpc/32: Fix vmap stack - Do not activate MMU before reading task struct")
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ce30364fb7ccda489272af4a1612b6aa147e1d23.1637227521.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cf0b0e3712f7af90006f8317ff27278094c2c128 upstream.
The POWER9 ERAT flush instruction is a SLBIA with IH=7, which is a
reserved value on POWER7/8. On POWER8 this invalidates the SLB entries
above index 0, similarly to SLBIA IH=0.
If the SLB entries are invalidated, and then the guest is bypassed, the
host SLB does not get re-loaded, so the bolted entries above 0 will be
lost. This can result in kernel stack access causing a SLB fault.
Kernel stack access causing a SLB fault was responsible for the infamous
mega bug (search "Fix SLB reload bug"). Although since commit
48e7b76957 ("powerpc/64s/hash: Convert SLB miss handlers to C") that
starts using the kernel stack in the SLB miss handler, it might only
result in an infinite loop of SLB faults. In any case it's a bug.
Fix this by only executing the instruction on >= POWER9 where IH=7 is
defined not to invalidate the SLB. POWER7/8 don't require this ERAT
flush.
Fixes: 5008711259 ("KVM: PPC: Book3S HV: Invalidate ERAT when flushing guest TLB entries")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211119031627.577853-1-npiggin@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1e35eba4055149c578baf0318d2f2f89ea3c44a0 upstream.
As spotted and explained in commit c12ab8dbc492 ("powerpc/8xx: Fix
Oops with STRICT_KERNEL_RWX without DEBUG_RODATA_TEST"), the selection
of STRICT_KERNEL_RWX without selecting DEBUG_RODATA_TEST has spotted
the lack of the DIRTY bit in the pinned kernel data TLBs.
This problem should have been detected a lot earlier if things had
been working as expected. But due to an incredible level of chance or
mishap, this went undetected because of a set of bugs: In fact the
DTLBs were not pinned, because instead of setting the reserve bit
in MD_CTR, it was set in MI_CTR that is the register for ITLBs.
But then, another huge bug was there: the physical address was
reset to 0 at the boundary between RO and RW areas, leading to the
same physical space being mapped at both 0xc0000000 and 0xc8000000.
This had by miracle no consequence until now because the entry was
not really pinned so it was overwritten soon enough to go undetected.
Of course, now that we really pin the DTLBs, it must be fixed as well.
Fixes: f76c8f6d25 ("powerpc/8xx: Add function to set pinned TLBs")
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Depends-on: c12ab8dbc492 ("powerpc/8xx: Fix Oops with STRICT_KERNEL_RWX without DEBUG_RODATA_TEST")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a21e9a057fe2d247a535aff0d157a54eefee017a.1636963688.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit dae581864609d36fb58855fd59880b4941ce9d14 ]
kvmppc_h_set_dabr(), and kvmppc_h_set_xdabr() which jumps into
it, need to use _GLOBAL_TOC to setup the kernel TOC pointer, because
kvmppc_h_set_dabr() uses LOAD_REG_ADDR() to load dawr_force_enable.
When called from hcall_try_real_mode() we have the kernel TOC in r2,
established near the start of kvmppc_interrupt_hv(), so there is no
issue.
But they can also be called from kvmppc_pseries_do_hcall() which is
module code, so the access ends up happening with the kvm-hv module's
r2, which will not point at dawr_force_enable and could even cause a
fault.
With the current code layout and compilers we haven't observed a fault
in practice, the load hits somewhere in kvm-hv.ko and silently returns
some bogus value.
Note that we we expect p8/p9 guests to use the DAWR, but SLOF uses
h_set_dabr() to test if sc1 works correctly, see SLOF's
lib/libhvcall/brokensc1.c.
Fixes: c1fe190c06 ("powerpc: Add force enable of DAWR on P9 option")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Daniel Axtens <dja@axtens.net>
Link: https://lore.kernel.org/r/20210923151031.72408-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fef071be57dc43679a32d5b0e6ee176d6f12e9f2 ]
In dcr-low.S we use cmpli with three arguments, instead of four
arguments as defined in the ISA:
cmpli cr0,r3,1024
This appears to be a PPC440-ism, looking at the "PPC440x5 CPU Core
User’s Manual" it shows cmpli having no L field, but implied to be 0 due
to the core being 32-bit. It mentions that the ISA defines four
arguments and recommends using cmplwi.
It also corresponds to the old POWER instruction set, which had no L
field there, a reserved bit instead.
dcr-low.S is only built 32-bit, because it is only built when
DCR_NATIVE=y, which is only selected by 40x and 44x. Looking at the
generated code (with gcc/gas) we see cmplwi as expected.
Although gas is happy with the 3-argument version when building for
32-bit, the LLVM assembler is not and errors out with:
arch/powerpc/sysdev/dcr-low.S:27:10: error: invalid operand for instruction
cmpli 0,%r3,1024; ...
^
Switch to the cmplwi extended opcode, which avoids any confusion when
reading the ISA, fixes the issue with the LLVM assembler, and also means
the code could be built 64-bit in future (though that's very unlikely).
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
BugLink: https://github.com/ClangBuiltLinux/linux/issues/1419
Link: https://lore.kernel.org/r/20211014024424.528848-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit aed2886a5e9ffc8269a4220bff1e9e030d3d2eb1 ]
Fixes build warnings:
Warning (unit_address_vs_reg): /memory: node has a reg or ranges property, but no unit name
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211013220532.24759-4-agust@denx.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit c45361abb9185b1e172bd75eff51ad5f601ccae4 upstream.
When CONFIG_SMP=y, timebase synchronization is required when the second
kernel is started.
arch/powerpc/kernel/smp.c:
int __cpu_up(unsigned int cpu, struct task_struct *tidle)
{
...
if (smp_ops->give_timebase)
smp_ops->give_timebase();
...
}
void start_secondary(void *unused)
{
...
if (smp_ops->take_timebase)
smp_ops->take_timebase();
...
}
When CONFIG_HOTPLUG_CPU=n and CONFIG_KEXEC_CORE=n,
smp_85xx_ops.give_timebase is NULL,
smp_85xx_ops.take_timebase is NULL,
As a result, the timebase is not synchronized.
Timebase synchronization does not depend on CONFIG_HOTPLUG_CPU.
Fixes: 56f1ba2807 ("powerpc/mpc85xx: refactor the PM operations")
Cc: stable@vger.kernel.org # v4.6+
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210929033646.39630-3-nixiaoming@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
upstream commit b7540d62509453263604a155bf2d5f0ed450cba2
Emit similar instruction sequences to commit a048a07d7f
("powerpc/64s: Add support for a store forwarding barrier at kernel
entry/exit") when encountering BPF_NOSPEC.
Mitigations are enabled depending on what the firmware advertises. In
particular, we do not gate these mitigations based on current settings,
just like in x86. Due to this, we don't need to take any action if
mitigations are enabled or disabled at runtime.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/956570cbc191cd41f8274bed48ee757a86dac62a.1633464148.git.naveen.n.rao@linux.vnet.ibm.com
[adjust macros to account for commits 1c9debbc2eb539 and ef909ba954145e.
adjust security feature checks to account for commit 84ed26fd00c514]
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
upstream commit 030905920f32e91a52794937f67434ac0b3ea41a
Add a helper to return the stf_barrier type for the current processor.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3bd5d7f96ea1547991ac2ce3137dc2b220bae285.1633464148.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
upstream commit 3832ba4e283d7052b783dab8311df7e3590fed93
Add checks to ensure that we never emit branch instructions with
truncated branch offsets.
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/71d33a6b7603ec1013c9734dd8bdd4ff5e929142.1633464148.git.naveen.n.rao@linux.vnet.ibm.com
[drop ppc32 changes]
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
upstream commit 4549c3ea3160fa8b3f37dfe2f957657bb265eda9
Add a helper to check if a given offset is within the branch range for a
powerpc conditional branch instruction, and update some sites to use the
new helper.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/442b69a34ced32ca346a0d9a855f3f6cfdbbbd41.1633464148.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 290fe8aa69ef5c51c778c0bb33f8ef0181c769f5 ]
Early exits from for_each_compatible_node() should decrement the
node reference counter. Reported by Coccinelle:
./arch/powerpc/platforms/44x/fsp2.c:206:1-25: WARNING: Function
"for_each_compatible_node" should have of_node_put() before return
around line 218.
Fixes: 7813043e1b ("powerpc/44x/fsp2: Add irq error handlers")
Signed-off-by: Bixuan Cui <cuibixuan@linux.alibaba.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1635406102-88719-1-git-send-email-cuibixuan@linux.alibaba.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 56537faf8821e361d739fc5ff58c9c40f54a1d4c ]
When check_kvm_guest() succeeds in looking up a /hypervisor OF node, it
returns without performing a matching put for the lookup, leaving the
node's reference count elevated.
Add the necessary call to of_node_put(), rearranging the code slightly to
avoid repetition or goto.
Fixes: 107c55005f ("powerpc/pseries: Add KVM guest doorbell restrictions")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210928124550.132020-1-nathanl@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
