- 30 Sep, 2022 2 commits
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Nicholas Piggin authored
PAPR specifies accumulated virtual processor wait intervals that relate to partition scheduling interval times. Implement these counters in the same way as they are repoted by dtl. Reviewed-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/20220908132545.4085849-5-npiggin@gmail.com
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Michael Ellerman authored
Merge some KVM commits we are keeping in our topic branch.
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- 28 Sep, 2022 38 commits
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Haren Myneni authored
The data storage interrupt (DSI) error will be generated when the paste operation is issued on the suspended Nest Accelerator (NX) window due to NX state changes. The hypervisor expects the partition to ignore this error during page fault handling. To differentiate DSI caused by an actual HW configuration or by the NX window, a new “ibm,pi-features” type value is defined. Byte 0, bit 3 of pi-attribute-specifier-type is now defined to indicate this DSI error. If this error is not ignored, the user space can get SIGBUS when the NX request is issued. This patch adds changes to read ibm,pi-features property and ignore DSI error during page fault handling if MMU_FTR_NX_DSI is defined. Signed-off-by:
Haren Myneni <haren@linux.ibm.com> [mpe: Mention PAPR version in comment] Signed-off-by:
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Michael Ellerman authored
On little endian the stack frame marker appears reversed when dumping memory sequentially, as is typical in xmon or gdb, eg: c000000004733e40 0000000000000000 0000000000000000 |................| c000000004733e50 0000000000000000 0000000000000000 |................| c000000004733e60 0000000000000000 0000000000000000 |................| c000000004733e70 5347455200000000 0000000000000000 |SGER............| c000000004733e80 a700000000000000 708897f7ff7f0000 |........p.......| c000000004733e90 0073428fff7f0000 208997f7ff7f0000 |.sB..... .......| c000000004733ea0 0100000000000000 ffffffffffffffff |................| c000000004733eb0 0000000000000000 0000000000000000 |................| To make it easier to recognise, reverse the value on little endian, so it always appears as "REGS", eg: c000000004733e70 5245475300000000 0000000000000000 |REGS............| Acked-by:
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Michael Ellerman authored
Now that the stack frame regs marker is only 32-bits it is not as obvious in memory dumps and easier to miss, eg: c000000004733e40 0000000000000000 0000000000000000 |................| c000000004733e50 0000000000000000 0000000000000000 |................| c000000004733e60 0000000000000000 0000000000000000 |................| c000000004733e70 7367657200000000 0000000000000000 |sger............| c000000004733e80 a700000000000000 708897f7ff7f0000 |........p.......| c000000004733e90 0073428fff7f0000 208997f7ff7f0000 |.sB..... .......| c000000004733ea0 0100000000000000 ffffffffffffffff |................| c000000004733eb0 0000000000000000 0000000000000000 |................| So make it upper case to make it stand out a bit more: c000000004733e70 5347455200000000 0000000000000000 |SGER............| Acked-by:
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Li Huafei authored
I found a null pointer reference in arch_prepare_kprobe(): # echo 'p cmdline_proc_show' > kprobe_events # echo 'p cmdline_proc_show+16' >> kprobe_events Kernel attempted to read user page (0) - exploit attempt? (uid: 0) BUG: Kernel NULL pointer dereference on read at 0x00000000 Faulting instruction address: 0xc000000000050bfc Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: CPU: 0 PID: 122 Comm: sh Not tainted 6.0.0-rc3-00007-gdcf8e563 #10 NIP: c000000000050bfc LR: c000000000050bec CTR: 0000000000005bdc REGS: c0000000348475b0 TRAP: 0300 Not tainted (6.0.0-rc3-00007-gdcf8e563) MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 88002444 XER: 20040006 CFAR: c00000000022d100 DAR: 0000000000000000 DSISR: 40000000 IRQMASK: 0 ... NIP arch_prepare_kprobe+0x10c/0x2d0 LR arch_prepare_kprobe+0xfc/0x2d0 Call Trace: 0xc0000000012f77a0 (unreliable) register_kprobe+0x3c0/0x7a0 __register_trace_kprobe+0x140/0x1a0 __trace_kprobe_create+0x794/0x1040 trace_probe_create+0xc4/0xe0 create_or_delete_trace_kprobe+0x2c/0x80 trace_parse_run_command+0xf0/0x210 probes_write+0x20/0x40 vfs_write+0xfc/0x450 ksys_write+0x84/0x140 system_call_exception+0x17c/0x3a0 system_call_vectored_common+0xe8/0x278 --- interrupt: 3000 at 0x7fffa5682de0 NIP: 00007fffa5682de0 LR: 0000000000000000 CTR: 0000000000000000 REGS: c000000034847e80 TRAP: 3000 Not tainted (6.0.0-rc3-00007-gdcf8e563) MSR: 900000000280f033 <SF,HV,VEC,VSX,EE,PR,FP,ME,IR,DR,RI,LE> CR: 44002408 XER: 00000000 The address being probed has some special: cmdline_proc_show: Probe based on ftrace cmdline_proc_show+16: Probe for the next instruction at the ftrace location The ftrace-based kprobe does not generate kprobe::ainsn::insn, it gets set to NULL. In arch_prepare_kprobe() it will check for: ... prev = get_kprobe(p->addr - 1); preempt_enable_no_resched(); if (prev && ppc_inst_prefixed(ppc_inst_read(prev->ainsn.insn))) { ... If prev is based on ftrace, 'ppc_inst_read(prev->ainsn.insn)' will occur with a null pointer reference. At this point prev->addr will not be a prefixed instruction, so the check can be skipped. Check if prev is ftrace-based kprobe before reading 'prev->ainsn.insn' to fix this problem. Fixes: b4657f76 ("powerpc/kprobes: Don't allow breakpoints on suffixes") Signed-off-by:
Li Huafei <lihuafei1@huawei.com> [mpe: Trim oops] Signed-off-by:
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ye xingchen authored
Return the value opal_npu_spa_clear_cache() directly instead of storing it in another redundant variable. Reported-by:
Zeal Robot <zealci@zte.com.cn> Signed-off-by:
ye xingchen <ye.xingchen@zte.com.cn> Acked-by:
Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by:
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ye xingchen authored
Return the value vas_register_coproc_api() directly instead of storing it in another redundant variable. Reported-by:
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Nathan Lynch authored
At boot time, it is not necessary to delay between polls of cpu_callin_map when waiting for a kicked CPU to come up. Remove the delay intervals, but preserve the overall deadline (five seconds). At run time, the first poll result is usually negative and we incur a sleeping wait. If we spin on the callin word for a short time first, we can reduce __cpu_up() from dozens of milliseconds to under 1ms in the common case on a P9 LPAR: $ ppc64_cpu --smt=off $ bpftrace -e 'kprobe:__cpu_up { @start[tid] = nsecs; } kretprobe:__cpu_up /@start[tid]/ { @us = hist((nsecs - @start[tid]) / 1000); delete(@start[tid]); }' -c 'ppc64_cpu --smt=on' Before: @us: [16K, 32K) 85 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [32K, 64K) 13 |@@@@@@@ | After: @us: [128, 256) 95 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [256, 512) 3 |@ | Signed-off-by:Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by:
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Nathan Lynch authored
The error injection facility on pseries VMs allows corruption of arbitrary guest memory, potentially enabling a sufficiently privileged user to disable lockdown or perform other modifications of the running kernel via the rtas syscall. Block the PAPR error injection facility from being opened or called when locked down. Signed-off-by:
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Nathan Lynch authored
The /proc/powerpc/ofdt interface allows the root user to freely alter the in-kernel device tree, enabling arbitrary physical address writes via drivers that could bind to malicious device nodes, thus making it possible to disable lockdown. Historically this interface has been used on the pseries platform to facilitate the runtime addition and removal of processor, memory, and device resources (aka Dynamic Logical Partitioning or DLPAR). Years ago, the processor and memory use cases were migrated to designs that happen to be lockdown-friendly: device tree updates are communicated directly to the kernel from firmware without passing through untrusted user space. I/O device DLPAR via the "drmgr" command in powerpc-utils remains the sole legitimate user of /proc/powerpc/ofdt, but it is already broken in lockdown since it uses /dev/mem to allocate argument buffers for the rtas syscall. So only illegitimate uses of the interface should see a behavior change when running on a locked down kernel. Signed-off-by:
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Pali Rohár authored
'extern' keyword is pointless and deprecated for function prototypes. Signed-off-by:
Pali Rohár <pali@kernel.org> Suggested-by:
Gabriel Paubert <paubert@iram.es> Signed-off-by:
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Pali Rohár authored
uImage boot wrapper should not use SPE instructions, like kernel itself. Boot wrapper has already disabled Altivec and VSX instructions but not SPE. Options -mno-spe and -mspe=no already set when compilation of kernel, but not when compiling uImage wrapper yet. Fix it. Cc: stable@vger.kernel.org Signed-off-by:
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Pali Rohár authored
There are still some board device tree files without Power ISA properties which have Freescale e500v1 cores, namely those which are based on Freescale mpc8540, mpc8541, mpc8555 and mpc8560 processors. So include newly introduced e500v1_power_isa.dtsi file in devices tree files with those processors. Signed-off-by:
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Pali Rohár authored
Commit 2eb28006 ("powerpc/e500v2: Add Power ISA properties to comply with ePAPR 1.1") introduced new include file e500v2_power_isa.dtsi and should have used it for all e500v2 platforms. But apparently it was used also for e500v1 platforms mpc8540, mpc8541, mpc8555 and mpc8560. e500v1 cores compared to e500v2 do not support double precision floating point SPE instructions. Hence power-isa-sp.fd should not be set on e500v1 platforms, which is in e500v2_power_isa.dtsi include file. Fix this issue by introducing a new e500v1_power_isa.dtsi include file and use it in all e500v1 device tree files. Fixes: 2eb28006 ("powerpc/e500v2: Add Power ISA properties to comply with ePAPR 1.1") Signed-off-by:
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Athira Rajeev authored
For PERF_SAMPLE_BRANCH_STACK sample type, different branch_sample_type, ie branch filters are supported. The testcase "bhrb_filter_map_test" tests the valid and invalid filter maps in different powerpc platforms. Update this testcase to include scenario to cover multiple branch filters at sametime. Since powerpc doesn't support multiple filters at sametime, expect failure during perf_event_open. Reported-by:
Disha Goel <disgoel@linux.vnet.ibm.com> Signed-off-by:
Athira Rajeev <atrajeev@linux.vnet.ibm.com> Reviewed-by:
Kajol Jain <kjain@linux.ibm.com> Signed-off-by:
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Athira Rajeev authored
For PERF_SAMPLE_BRANCH_STACK sample type, different branch_sample_type ie branch filters are supported. The branch filters are requested via event attribute "branch_sample_type". Multiple branch filters can be passed in event attribute. eg: $ perf record -b -o- -B --branch-filter any,ind_call true None of the Power PMUs support having multiple branch filters at the same time. Branch filters for branch stack sampling is set via MMCRA IFM bits [32:33]. But currently when requesting for multiple filter types, the "perf record" command does not report any error. eg: $ perf record -b -o- -B --branch-filter any,save_type true $ perf record -b -o- -B --branch-filter any,ind_call true The "bhrb_filter_map" function in PMU driver code does the validity check for supported branch filters. But this check is done for single filter. Hence "perf record" will proceed here without reporting any error. Fix power_pmu_event_init() to return EOPNOTSUPP when multiple branch filters are requested in the event attr. After the fix: $ perf record --branch-filter any,ind_call -- ls Error: cycles: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat' Reported-by:
Madhavan Srinivasan <maddy@linux.ibm.com> Reviewed-by:
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Nicholas Piggin authored
Ensure r13 is zero from very early in boot until it gets set to the boot paca pointer. This allows early program and mce handlers to halt if there is no valid paca, rather than potentially run off into the weeds. This preserves register and memory contents for low level debugging tools. Nothing could be printed to console at this point in any case because even udbg is only set up after the boot paca is set, so this shouldn't be missed. Signed-off-by:
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Nicholas Piggin authored
The idea is to get to the point where if r13 is non-zero, then it should contain a reasonable paca. This can be used in early boot program check and machine check handlers to avoid running off into the weeds if they hit before r13 has a paca. Signed-off-by:
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Nicholas Piggin authored
relocate() uses r13 in early boot before it is used for the paca. Use a different register for this so r13 is kept unchanged until it is set to the paca pointer. Avoid r14 as well while we're here, there's no reason not to use the volatile registers which is a bit less surprising, and r14 could be used as another fixed reg one day. Signed-off-by:
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Nicholas Piggin authored
Use the early boot interrupt fixup in the machine check handler to allow the machine check handler to run before interrupt endian is set up. Branch to an early boot handler that just does a basic crash, which allows it to run before ppc_md is set up. MSR[ME] is enabled on the boot CPU earlier, and the machine check stack is temporarily set to the middle of the init task stack. This allows machine checks (e.g., due to invalid data access in real mode) to print something useful earlier in boot (as soon as udbg is set up, if CONFIG_PPC_EARLY_DEBUG=y). Signed-off-by:
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Nicholas Piggin authored
In preparation for using this sequence in machine check interrupt, move it into a macro, with a small change to make it position independent. Signed-off-by:
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Nicholas Piggin authored
The interrupt entry code carefully saves a minimal number of registers, so in some places the TOC is required, it is loaded into a different register, so provide a macro that can supply an alternate TOC register. This continues to use got addressing because TOC-relative results in "got/toc optimization is not supported" messages by the linker. Having r2 be one of the saved registers and using that for TOC addressing may be the best way to avoid that and switch this to TOC addressing. Signed-off-by:
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Nicholas Piggin authored
A later change stops the kernel using r2 and loads it with a poison value. Provide a PACATOC loading abstraction which can hide this detail. Signed-off-by:
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Nicholas Piggin authored
There is no need to use GOT addressing within the kernel. Signed-off-by:
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Nicholas Piggin authored
Use helper macros to access global variables, and place them in .data sections rather than in .toc. Putting addresses in TOC is not required because the kernel is linked with a single TOC. Signed-off-by:
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Nicholas Piggin authored
Using a 32-bit constant for this marker allows it to be loaded with two ALU instructions, like 32-bit. This avoids a TOC entry and a TOC load that depends on the r2 value that has just been loaded from the PACA. This changes the value for 32-bit as well, so both have the same value in the low 4 bytes and 64-bit has 0 in the top bytes. Signed-off-by:
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Nicholas Piggin authored
This adds basic POWER10_CPU option, which builds with -mcpu=power10. Signed-off-by:
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Haren Myneni authored
When the migration is initiated, the hypervisor changes VAS mappings as part of pre-migration event. Then the OS gets the migration event which closes all VAS windows before the migration starts. NX generates continuous faults until windows are closed and the user space can not differentiate these NX faults coming from the actual migration. So to reduce this time window, close VAS windows first in pseries_migrate_partition(). Signed-off-by:
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Nicholas Piggin authored
irq replay is quite complicated because of softirq processing which itself enables and disables irqs. Several considerations need to be accounted for due to this, and they are not clearly documented. Refactor the irq replay code a bit to tidy and deduplicate some common functions. Add comments, debug checks. This has a minor functional change that irq tracing enable/disable is done after each interrupt replayed, rather than after a batch. It also re-sets state to IRQS_ALL_DISABLED after an interrupt, which doesn't matter much because interrupts are hard disabled at this point, but it is more consistent with how interrupt handlers are called. Signed-off-by:
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Nicholas Piggin authored
BUG/WARN are handled with a program interrupt which can turn into an infinite recursion when there are bugs in interrupt handler entry (which can be irritated by bugs in other parts of the code). There is one feeble attempt to avoid this recursion, but it misses several cases. Make a tidier macro for this and switch most bugs in the interrupt entry wrapper over to use it. Signed-off-by:
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Nicholas Piggin authored
Prior changes eliminated cases of masked PACA_IRQ_MUST_HARD_MASK interrupts that re-fire due to MSR[EE] being enabled while they are pending. Add a debug check in the masked interrupt handler to catch if this occurs. Signed-off-by:
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Nicholas Piggin authored
When irqs are soft-disabled, MSR[EE] is volatile and can change from 1 to 0 asynchronously (if a PACA_IRQ_MUST_HARD_MASK interrupt hits). So it can not be used to check hard IRQ enabled status, except to confirm it is disabled. ppc64_runlatch_on/off functions use MSR this way to decide whether to re-enable MSR[EE] after disabling it, which leads to MSR[EE] being enabled when it shouldn't be (when a PACA_IRQ_MUST_HARD_MASK had disabled it between reading the MSR and clearing EE). This has been tolerated in the kernel previously, and it doesn't seem to cause a problem, but it is unexpected and may trip warnings or cause other problems as we tighten up this state management. Fix this by only re-enabling if PACA_IRQ_HARD_DIS is clear. Signed-off-by:
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Nicholas Piggin authored
If a synchronous interrupt (e.g., hash fault) is taken inside an irqs-disabled region which has MSR[EE]=1, then an asynchronous interrupt that is PACA_IRQ_MUST_HARD_MASK (e.g., PMI) is taken inside the synchronous interrupt handler, then the synchronous interrupt will return with MSR[EE]=1 and the asynchronous interrupt fires again. If the asynchronous interrupt is a PMI and the original context does not have PMIs disabled (only Linux IRQs), the asynchronous interrupt will fire despite having the PMI marked soft pending. This can confuse the perf code and cause warnings. This patch changes the interrupt return so that irqs-disabled MSR[EE]=1 contexts will be returned to with MSR[EE]=0 if a PACA_IRQ_MUST_HARD_MASK interrupt has become pending in the meantime. The longer explanation for what happens: 1. local_irq_disable() 2. Hash fault interrupt fires, do_hash_fault handler runs 3. interrupt_enter_prepare() sets IRQS_ALL_DISABLED 4. interrupt_enter_prepare() sets MSR[EE]=1 5. PMU interrupt fires, masked handler runs 6. Masked handler marks PMI pending 7. Masked handler returns with PACA_IRQ_HARD_DIS set, MSR[EE]=0 8. do_hash_fault interrupt return handler runs 9. interrupt_exit_kernel_prepare() clears PACA_IRQ_HARD_DIS 10. interrupt returns with MSR[EE]=1 11. PMU interrupt fires, perf handler runs Fixes: 4423eb5a ("powerpc/64/interrupt: make normal synchronous interrupts enable MSR[EE] if possible") Signed-off-by:
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Nicholas Piggin authored
This prevents interrupts in early boot (e.g., program check) from enabling MSR[EE], potentially causing endian mismatch or other crashes when reporting early boot traps. Fixes: 4423eb5a ("powerpc/64/interrupt: make normal synchronous interrupts enable MSR[EE] if possible") Signed-off-by:
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Nicholas Piggin authored
Commit 17147677 ("context_tracking: Convert state to atomic_t") added a CONTEXT_IDLE state which can be encountered by interrupts from kernel mode in the idle thread, causing a false positive warning. Fixes: 17147677 ("context_tracking: Convert state to atomic_t") Signed-off-by:
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Nicholas Miehlbradt authored
KFENCE support was added for ppc32 in commit 90cbac0e ("powerpc: Enable KFENCE for PPC32"). Enable KFENCE on ppc64 architecture with hash and radix MMUs. It uses the same mechanism as debug pagealloc to protect/unprotect pages. All KFENCE kunit tests pass on both MMUs. KFENCE memory is initially allocated using memblock but is later marked as SLAB allocated. This necessitates the change to __pud_free to ensure that the KFENCE pages are freed appropriately. Based on previous work by Christophe Leroy and Jordan Niethe. Signed-off-by:
Nicholas Miehlbradt <nicholas@linux.ibm.com> Reviewed-by:
Russell Currey <ruscur@russell.cc> Signed-off-by:
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Christophe Leroy authored
If the page is already mapped resp. already unmapped, bail out. Signed-off-by:
Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by:
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Christophe Leroy authored
debug_pagealloc_enabled() is always defined and constant folds to 'false' when CONFIG_DEBUG_PAGEALLOC is not enabled. Remove the #ifdefs, the code and associated static variables will be optimised out by the compiler when CONFIG_DEBUG_PAGEALLOC is not defined. Signed-off-by:
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Nicholas Miehlbradt authored
There is support for DEBUG_PAGEALLOC on hash but not on radix. Add support on radix. Signed-off-by:
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