- 29 Jul, 2020 30 commits
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Aneesh Kumar K.V authored
This adds a kernel command line option that can be used to disable GTSE support. Disabling GTSE implies kernel will make hcalls to invalidate TLB entries. This was done so that we can do VM migration between configs that enable/disable GTSE support via hypervisor. To migrate a VM from a system that supports GTSE to a system that doesn't, we can boot the guest with radix_hcall_invalidate=on, thereby forcing the guest to use hcalls for TLB invalidates. The check for hcall availability is done in pSeries_setup_arch so that the panic message appears on the console. This should only happen on a hypervisor that doesn't force the guest to hash translation even though it can't handle the radix GTSE=0 request via CAS. With radix_hcall_invalidate=on if the hypervisor doesn't support hcall_rpt_invalidate hcall it should force the LPAR to hash translation. Signed-off-by:
Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Tested-by:
Bharata B Rao <bharata@linux.ibm.com> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200727085908.420806-1-aneesh.kumar@linux.ibm.com
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Aneesh Kumar K.V authored
Current kernel gives: [ 0.000000] cma: Reserved 26224 MiB at 0x0000007959000000 [ 0.000000] hugetlb_cma: reserve 65536 MiB, up to 16384 MiB per node [ 0.000000] cma: Reserved 16384 MiB at 0x0000001800000000 With the fix [ 0.000000] kvm_cma_reserve: reserving 26214 MiB for global area [ 0.000000] cma: Reserved 26224 MiB at 0x0000007959000000 [ 0.000000] hugetlb_cma: reserve 65536 MiB, up to 16384 MiB per node [ 0.000000] cma: Reserved 16384 MiB at 0x0000001800000000 Signed-off-by:
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Aneesh Kumar K.V authored
commit: cf11e85f ("mm: hugetlb: optionally allocate gigantic hugepages using cma") added support for allocating gigantic hugepages using CMA. This patch enables the same for powerpc Signed-off-by:
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Balamuruhan S authored
Data Cache Block Invalidate (dcbi) instruction implemented back in PowerPC architecture version 2.03. But as per Power Processor Users Manual it is obsolete and not supported by POWER8/POWER9 core. Attempt to use of this illegal instruction results in a hypervisor emulation assistance interrupt. So, ifdef it out the option `i` in xmon for 64bit Book3S. 0:mon> fi cpu 0x0: Vector: 700 (Program Check) at [c000000003be74a0] pc: c000000000102030: cacheflush+0x180/0x1a0 lr: c000000000101f3c: cacheflush+0x8c/0x1a0 sp: c000000003be7730 msr: 8000000000081033 current = 0xc0000000035e5c00 paca = 0xc000000001910000 irqmask: 0x03 irq_happened: 0x01 pid = 1025, comm = bash Linux version 5.6.0-rc5-g5aa19adac (root@ltc-wspoon6) (gcc version 7.4.0 (Ubuntu 7.4.0-1ubuntu1~18.04.1)) #1 SMP Tue Mar 10 04:38:41 CDT 2020 cpu 0x0: Exception 700 (Program Check) in xmon, returning to main loop [c000000003be7c50] c00000000084abb0 __handle_sysrq+0xf0/0x2a0 [c000000003be7d00] c00000000084b3c0 write_sysrq_trigger+0xb0/0xe0 [c000000003be7d30] c0000000004d1edc proc_reg_write+0x8c/0x130 [c000000003be7d60] c00000000040dc7c __vfs_write+0x3c/0x70 [c000000003be7d80] c000000000410e70 vfs_write+0xd0/0x210 [c000000003be7dd0] c00000000041126c ksys_write+0xdc/0x130 [c000000003be7e20] c00000000000b9d0 system_call+0x5c/0x68 --- Exception: c01 (System Call) at 00007fffa345e420 SP (7ffff0b08ab0) is in userspace Signed-off-by:Balamuruhan S <bala24@linux.ibm.com> Signed-off-by:
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Michael Ellerman authored
There's a comment in time.h referring to CONFIG_POWER, which doesn't exist. That confuses scripts/checkkconfigsymbols.py. Presumably the comment was referring to a CONFIG_POWER vs CONFIG_PPC, in which case for CONFIG_POWER we would #define __USE_RTC to 1. But instead we have CONFIG_PPC_BOOK3S_601, and these days we have IS_ENABLED(). So the comment is no longer relevant, drop it. Signed-off-by:
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Michael Ellerman authored
This comment refers to the non-existent CONFIG_PPC_BOOK3S_XX, which confuses scripts/checkkconfigsymbols.py. Change it to use the correct symbol. Signed-off-by:
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Michael Ellerman authored
Commit 866bfc75 ("powerpc: conditionally compile platform-specific serial drivers") made some code depend on CONFIG_PPC_MPC52XX, which doesn't exist. Fix it to use CONFIG_PPC_MPC52xx. Fixes: 866bfc75 ("powerpc: conditionally compile platform-specific serial drivers") Signed-off-by:
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Michael Ellerman authored
All 32 and 64-bit builds that don't have CONFIG_TAU_INT enabled (all of them), get a definition of TAUException() in traps.c. On 64-bit it's completely useless, and just wastes ~120 bytes of text. On 32-bit it allows the kernel to link because head_32.S calls it unconditionally. Instead follow the example of altivec_assist_exception(), and if CONFIG_TAU_INT is not enabled just point it at unknown_exception using the preprocessor. Signed-off-by:
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Michael Ellerman authored
We have two uses of CONFIG_BOOK3S_601, which doesn't exist. Fix them to use CONFIG_PPC_BOOK3S_601 which is the correct symbol. Fixes: 12c3f1fd ("powerpc/32s: get rid of CPU_FTR_601 feature") Signed-off-by:
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Michael Ellerman authored
This code was merged 11 years ago in commit 13363ab9 ("powerpc: Add definitions used by exception handling on 64-bit Book3E") but was never able to be built because CONFIG_BOOK3E_MMU_TLB_STATS never existed. Remove it. Signed-off-by:
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Michael Ellerman authored
There's a comment in lite5200_sleep.S that refers to "CONFIG_BDI*". This confuses scripts/checkkconfigsymbols.py, which thinks it should be able to find CONFIG_BDI. Change the comment to refer to CONFIG_BDI_SWITCH which is presumably roughly what it was referring to. AFAICS there never has been a CONFIG_BDI. Signed-off-by:
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Michael Ellerman authored
Remove references to symbols that no longer exist as reported by scripts/checkkconfigsymbols.py. Signed-off-by:
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Michael Ellerman authored
ppc6xx_defconfig refers to quite a few symbols that no longer exist, as reported by scripts/checkkconfigsymbols.py, remove them. Signed-off-by:
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Bharata B Rao authored
During memory hotplug and unplug, resize_hpt_for_hotplug() gets called for both hash and radix guests but it should be called only for hash guests. Though the call does nothing in the radix guest case, it is cleaner to push this call into hash specific memory hotplug routines. Reported-by:
Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by:
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Michael Ellerman authored
Now that the powerpc code behaves the same as other architectures we can drop the special cases we had. Signed-off-by:
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Michael Ellerman authored
We have powerpc specific logic in our page fault handling to decide if an access to an unmapped address below the stack pointer should expand the stack VMA. The logic aims to prevent userspace from doing bad accesses below the stack pointer. However as long as the stack is < 1MB in size, we allow all accesses without further checks. Adding some debug I see that I can do a full kernel build and LTP run, and not a single process has used more than 1MB of stack. So for the majority of processes the logic never even fires. We also recently found a nasty bug in this code which could cause userspace programs to be killed during signal delivery. It went unnoticed presumably because most processes use < 1MB of stack. The generic mm code has also grown support for stack guard pages since this code was originally written, so the most heinous case of the stack expanding into other mappings is now handled for us. Finally although some other arches have special logic in this path, from what I can tell none of x86, arm64, arm and s390 impose any extra checks other than those in expand_stack(). So drop our complicated logic and like other architectures just let the stack expand as long as its within the rlimit. Signed-off-by:
Daniel Axtens <dja@axtens.net> Link: https://lore.kernel.org/r/20200724092528.1578671-4-mpe@ellerman.id.au
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Michael Ellerman authored
Update the stack expansion load/store test to take into account the new allowance of 4224 bytes below the stack pointer. Signed-off-by:
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Michael Ellerman authored
We have powerpc specific logic in our page fault handling to decide if an access to an unmapped address below the stack pointer should expand the stack VMA. The code was originally added in 2004 "ported from 2.4". The rough logic is that the stack is allowed to grow to 1MB with no extra checking. Over 1MB the access must be within 2048 bytes of the stack pointer, or be from a user instruction that updates the stack pointer. The 2048 byte allowance below the stack pointer is there to cover the 288 byte "red zone" as well as the "about 1.5kB" needed by the signal delivery code. Unfortunately since then the signal frame has expanded, and is now 4224 bytes on 64-bit kernels with transactional memory enabled. This means if a process has consumed more than 1MB of stack, and its stack pointer lies less than 4224 bytes from the next page boundary, signal delivery will fault when trying to expand the stack and the process will see a SEGV. The total size of the signal frame is the size of struct rt_sigframe (which includes the red zone) plus __SIGNAL_FRAMESIZE (128 bytes on 64-bit). The 2048 byte allowance was correct until 2008 as the signal frame was: struct rt_sigframe { struct ucontext uc; /* 0 1440 */ /* --- cacheline 11 boundary (1408 bytes) was 32 bytes ago --- */ long unsigned int _unused[2]; /* 1440 16 */ unsigned int tramp[6]; /* 1456 24 */ struct siginfo * pinfo; /* 1480 8 */ void * puc; /* 1488 8 */ struct siginfo info; /* 1496 128 */ /* --- cacheline 12 boundary (1536 bytes) was 88 bytes ago --- */ char abigap[288]; /* 1624 288 */ /* size: 1920, cachelines: 15, members: 7 */ /* padding: 8 */ }; 1920 + 128 = 2048 Then in commit ce48b210 ("powerpc: Add VSX context save/restore, ptrace and signal support") (Jul 2008) the signal frame expanded to 2304 bytes: struct rt_sigframe { struct ucontext uc; /* 0 1696 */ <-- /* --- cacheline 13 boundary (1664 bytes) was 32 bytes ago --- */ long unsigned int _unused[2]; /* 1696 16 */ unsigned int tramp[6]; /* 1712 24 */ struct siginfo * pinfo; /* 1736 8 */ void * puc; /* 1744 8 */ struct siginfo info; /* 1752 128 */ /* --- cacheline 14 boundary (1792 bytes) was 88 bytes ago --- */ char abigap[288]; /* 1880 288 */ /* size: 2176, cachelines: 17, members: 7 */ /* padding: 8 */ }; 2176 + 128 = 2304 At this point we should have been exposed to the bug, though as far as I know it was never reported. I no longer have a system old enough to easily test on. Then in 2010 commit 320b2b8d ("mm: keep a guard page below a grow-down stack segment") caused our stack expansion code to never trigger, as there was always a VMA found for a write up to PAGE_SIZE below r1. That meant the bug was hidden as we continued to expand the signal frame in commit 2b0a576d ("powerpc: Add new transactional memory state to the signal context") (Feb 2013): struct rt_sigframe { struct ucontext uc; /* 0 1696 */ /* --- cacheline 13 boundary (1664 bytes) was 32 bytes ago --- */ struct ucontext uc_transact; /* 1696 1696 */ <-- /* --- cacheline 26 boundary (3328 bytes) was 64 bytes ago --- */ long unsigned int _unused[2]; /* 3392 16 */ unsigned int tramp[6]; /* 3408 24 */ struct siginfo * pinfo; /* 3432 8 */ void * puc; /* 3440 8 */ struct siginfo info; /* 3448 128 */ /* --- cacheline 27 boundary (3456 bytes) was 120 bytes ago --- */ char abigap[288]; /* 3576 288 */ /* size: 3872, cachelines: 31, members: 8 */ /* padding: 8 */ /* last cacheline: 32 bytes */ }; 3872 + 128 = 4000 And commit 573ebfa6 ("powerpc: Increase stack redzone for 64-bit userspace to 512 bytes") (Feb 2014): struct rt_sigframe { struct ucontext uc; /* 0 1696 */ /* --- cacheline 13 boundary (1664 bytes) was 32 bytes ago --- */ struct ucontext uc_transact; /* 1696 1696 */ /* --- cacheline 26 boundary (3328 bytes) was 64 bytes ago --- */ long unsigned int _unused[2]; /* 3392 16 */ unsigned int tramp[6]; /* 3408 24 */ struct siginfo * pinfo; /* 3432 8 */ void * puc; /* 3440 8 */ struct siginfo info; /* 3448 128 */ /* --- cacheline 27 boundary (3456 bytes) was 120 bytes ago --- */ char abigap[512]; /* 3576 512 */ <-- /* size: 4096, cachelines: 32, members: 8 */ /* padding: 8 */ }; 4096 + 128 = 4224 Then finally in 2017, commit 1be7107f ("mm: larger stack guard gap, between vmas") exposed us to the existing bug, because it changed the stack VMA to be the correct/real size, meaning our stack expansion code is now triggered. Fix it by increasing the allowance to 4224 bytes. Hard-coding 4224 is obviously unsafe against future expansions of the signal frame in the same way as the existing code. We can't easily use sizeof() because the signal frame structure is not in a header. We will either fix that, or rip out all the custom stack expansion checking logic entirely. Fixes: ce48b210 ("powerpc: Add VSX context save/restore, ptrace and signal support") Cc: stable@vger.kernel.org # v2.6.27+ Reported-by:Tom Lane <tgl@sss.pgh.pa.us> Tested-by:
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Michael Ellerman authored
We have custom stack expansion checks that it turns out are extremely badly tested and contain bugs, surprise. So add some tests that exercise the code and capture the current boundary conditions. The signal test currently fails on 64-bit kernels because the 2048 byte allowance for the signal frame is too small, we will fix that in a subsequent patch. Signed-off-by:
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Oliver O'Halloran authored
For drivers that don't have the error handling callbacks we implement recovery by removing the device and re-probing it. This causes the sysfs directory for the PCI device to be removed which causes the following spurious error to be printed when checking the PE state: Breaking 0005:03:00.0... ./eeh-basic.sh: line 13: can't open /sys/bus/pci/devices/0005:03:00.0/eeh_pe_state: no such file 0005:03:00.0, waited 0/60 0005:03:00.0, waited 1/60 0005:03:00.0, waited 2/60 0005:03:00.0, waited 3/60 0005:03:00.0, waited 4/60 0005:03:00.0, waited 5/60 0005:03:00.0, waited 6/60 0005:03:00.0, waited 7/60 0005:03:00.0, Recovered after 8 seconds We currently try to avoid this by checking if the PE state file exists before reading from it. This is however inherently racy so re-work the state checking so that we only read from the file once, and we squash any errors that occur while reading. Fixes: 85d86c8a ("selftests/powerpc: Add basic EEH selftest") Signed-off-by:
Oliver O'Halloran <oohall@gmail.com> Signed-off-by:
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Sandipan Das authored
Commit c46241a3 ("powerpc/pkeys: Check vma before returning key fault error to the user") fixes a bug which causes the kernel to set the wrong pkey in siginfo when a pkey fault occurs after two competing threads that have allocated different pkeys, one fully permissive and the other restrictive, attempt to protect a common page at the same time. This adds a test to detect the bug. Signed-off-by:
Sandipan Das <sandipan@linux.ibm.com> Signed-off-by:
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Sandipan Das authored
The gettid() syscall wrapper was first introduced in glibc 2.30. This adds a wrapper for use in distros running older versions. Suggested-by:
Christophe Leroy <christophe.leroy@csgroup.eu> Suggested-by:
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Sandipan Das authored
This adds a helper similar to FAIL_IF() which lets a program exit with code 1 (to indicate failure) when the given condition is true. Signed-off-by:
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Sandipan Das authored
Commit 192b6a78 ("powerpc/book3s64/pkeys: Fix pkey_access_permitted() for execute disable pkey") fixed a bug that caused repetitive faults for pkeys with no execute rights alongside some combination of read and write rights. This removes the last two cases of the test, which check the behaviour of pkeys with read, write but no execute rights and all the rights, in favour of checking all the possible combinations of read, write and execute rights to be able to detect bugs like the one mentioned above. Signed-off-by:
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Sandipan Das authored
This adds some new pkey-related helper to print access rights of a pkey in the "rwx" format and to generate different valid combinations of pkey rights starting from a given combination. Signed-off-by:
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Sandipan Das authored
This moves all the pkey-related helpers to a new header file and also a helper to print error messages in signal handlers to the existing utils header file. Signed-off-by:
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Nicholas Piggin authored
KVM guests have certain restrictions and performance quirks when using doorbells. This patch moves the EPAPR KVM guest test so it can be shared with PSERIES, and uses that in doorbell setup code to apply the KVM guest quirks and improves IPI performance for two cases: - PowerVM guests may now use doorbells even if they are secure. - KVM guests no longer use doorbells if XIVE is available. There is a valid complaint that "KVM guest" is not a very reasonable thing to test for, it's preferable for the hypervisor to advertise particular behaviours to the guest so they could change if the hypervisor implementation or configuration changes. However in this case we were already assuming a KVM guest worst case, so this patch is about containing those quirks. If KVM later advertises fast doorbells, we should test for that and override the quirks. Signed-off-by:
Nicholas Piggin <npiggin@gmail.com> Tested-by:
Cédric Le Goater <clg@kaod.org> Signed-off-by:
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Nicholas Piggin authored
KVM supports msgsndp in guests by trapping and emulating the instruction, so it was decided to always use XIVE for IPIs if it is available. However on PowerVM systems, msgsndp can be used and gives better performance. On large systems, high XIVE interrupt rates can have sub-linear scaling, and using msgsndp can reduce the load on the interrupt controller. So switch to using core local doorbells even if XIVE is available. This reduces performance for KVM guests with an SMT topology by about 50% for ping-pong context switching between SMT vCPUs. An option vector (or dt-cpu-ftrs) could be defined to disable msgsndp to get KVM performance back. Signed-off-by:
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Nicholas Piggin authored
These are only called in one place for a given platform, so inline them for performance. Signed-off-by:
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Athira Rajeev authored
Commit 9908c826 ("powerpc/perf: Add Power10 PMU feature to DT CPU features") defines MMCRA_BHRB_DISABLE as `0x2000000000UL`. Binutils version less than 2.28 doesn't support UL suffix. arch/powerpc/kernel/cpu_setup_power.S: Assembler messages: arch/powerpc/kernel/cpu_setup_power.S:250: Error: found 'L', expected: ')' arch/powerpc/kernel/cpu_setup_power.S:250: Error: junk at end of line, first unrecognized character is `L' arch/powerpc/kernel/cpu_setup_power.S:250: Error: found 'L', expected: ')' arch/powerpc/kernel/cpu_setup_power.S:250: Error: found 'L', expected: ')' arch/powerpc/kernel/cpu_setup_power.S:250: Error: junk at end of line, first unrecognized character is `L' arch/powerpc/kernel/cpu_setup_power.S:250: Error: found 'L', expected: ')' arch/powerpc/kernel/cpu_setup_power.S:250: Error: found 'L', expected: ')' arch/powerpc/kernel/cpu_setup_power.S:250: Error: operand out of range (0x0000002000000000 is not between 0xffffffffffff8000 and 0x000000000000ffff) Fix this by wrapping it with the `_UL` macro. Fixes: 9908c826 ("Add Power10 PMU feature to DT CPU features") Suggested-by:
Athira Rajeev <atrajeev@linux.vnet.ibm.com> Reviewed-by:
Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by:
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- 27 Jul, 2020 1 commit
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Michael Ellerman authored
skiroot_defconfig fails: arch/powerpc/kernel/fadump.c:48:17: error: ‘cpus_in_fadump’ defined but not used 48 | static atomic_t cpus_in_fadump; Fix it by moving the definition into the #ifdef where it's used. Fixes: ba608c4f ("powerpc/fadump: fix race between pstore write and fadump crash trigger") Signed-off-by:
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- 26 Jul, 2020 9 commits
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Randy Dunlap authored
Drop the repeated word "for". Signed-off-by:
Randy Dunlap <rdunlap@infradead.org> Signed-off-by:
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Randy Dunlap authored
Drop the repeated word "the". Signed-off-by:
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Randy Dunlap authored
Drop the repeated word "a". Signed-off-by:
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Randy Dunlap authored
Drop the repeated word "in". Signed-off-by:
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Randy Dunlap authored
Drop the repeated word "the". Signed-off-by:
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Randy Dunlap authored
Drop the repeated words "file" and "the". Signed-off-by:
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Randy Dunlap authored
Drop the repeated word "use". Signed-off-by:
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Randy Dunlap authored
Drop the repeated word "per". Signed-off-by:
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Randy Dunlap authored
Drop the repeated word "below". Signed-off-by:
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