Re: [fake numa not working] [PATCH 1/1] mm/fake-numa: allow later numa node hotplug

Hyeonggon Yoo
2025-01-20T02:37:29Z

On 1/20/2025 11:16 AM, Zi Yan wrote:
> On Sun Jan 19, 2025 at 7:37 PM EST, Hyeonggon Yoo wrote:
>>
>>
>> On 1/18/2025 4:09 AM, Zi Yan wrote:
>>> On 17 Jan 2025, at 0:00, Hyeonggon Yoo wrote:
>>>
>>>> On 1/6/2025 9:06 PM, Bruno Faccini wrote:
>>>>> Current fake-numa implementation prevents new Numa
>>>>> nodes to be later hot-plugged by drivers.
>>>>> A common symptom of this limitation is the
>>>>> "node <X> was absent from the node_possible_map"
>>>>> message by associated warning in mm/memory_hotplug.c:
>>>>> add_memory_resource().
>>>>> This comes from the lack of remapping in both
>>>>> pxm_to_node_map[] and node_to_pxm_map[] tables
>>>>> to take fake-numa nodes into account and thus
>>>>> triggers collisions with original and physical nodes
>>>>> only-mapping that had been determined from BIOS tables.
>>>>> This patch fixes this by doing the necessary node-ids
>>>>> translation in both pxm_to_node_map[]/node_to_pxm_map[]
>>>>> tables.
>>>>> node_distance[] table has also been fixed accordingly.
>>>>>
>>>>> Signed-off-by: Bruno Faccini <bfaccini@nvidia.com>
>>>>
>>>> Hi Bruno,
>>>>
>>>> This commit causes WARN() and disables fakenuma
>>>> when I pass "numa=fake=4U" on my QEMU setup.
>>>>
>>>> Attaching WARN() log and git bisect log to help debugging.
>>>
>>> Is your VM getting 4 NUMA nodes at the end?
>>
>> No, it only gets node 0 at the end.
>
> Got it.
>
>>
>>> Can you also share your QEMU command line and your kernel config?
>>
>> The config is attached (fakenuma.config)
>>
>> QEMU command line:
>> $ qemu-system-x86_64 \
>> -cpu host \
>> -enable-kvm \
>> -smp $(nproc) \
>> -m 32G \
>> -nographic \
>> -kernel arch/x86/boot/bzImage \
>> -initrd ../../rootfs.cpio.gz \
>> -nic user,model=virtio-net-pci \
>> -append "console=ttyS0 numa=fake=4U"
>>
>>> This can help Bruno reproduce the issue locally. At least, I
>>> cannot reproduce it on mm-everything-2025-01-16-23-18.
>>
>> Still reproduced on mm-everything-2025-01-18-04-55 with my setup.
>>
>>> I also
>>> notice that my VM does not have “No NUMA configuration found”
>>> (in your log) in its kernel log and that might explain
>>> why I could not reproduce it.
>>
>> Did you do NUMA configuration (-numa in QEMU) for your VM?
>> I didn't, but it's still expected to work 'cause it's fake numa.
>
> No. It seems that the "No NUMA configuration found" is caused by your
> qemu, where dummy_numa_init() is used (maybe ACPI SRAT is not
> populated?)

FYI, Yes. ACPI SRAT is not populated.

$ qemu-system-x86_64 --version
QEMU emulator version 6.2.0 (Debian 1:6.2+dfsg-2ubuntu6.24)
Copyright (c) 2003-2021 Fabrice Bellard and the QEMU Project developers

> I used the patch below to emulate the situation and
> reproduced the issue. Since dummy_numa_init() is used when there is
> no underlying NUMA architecture, NUMA initialization fails, or NUMA
> is disabled on the command line (the last does not apply here),
> it should be properly handled. I will let Bruno look into it.
>
> Thank you for the info.
>
> diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
> index 64e5cdb2460a..70dfd9bfb23f 100644
> --- a/arch/x86/mm/numa.c
> +++ b/arch/x86/mm/numa.c
> @@ -223,7 +223,7 @@ static int __init dummy_numa_init(void)
> */
> void __init x86_numa_init(void)
> {
> - if (!numa_off) {
> + if (0 && !numa_off) {
> #ifdef CONFIG_ACPI_NUMA
> if (!numa_init(x86_acpi_numa_init))
> return;
>
>>>>
>>>> [WARN() splat]
>>>>
>>>> [ 0.009676] No NUMA configuration found
>>>> [ 0.009677] Faking a node at [mem 0x0000000000000000-0x000000083fffffff]
>>>> [ 0.009705] Fake node size 16895MB too small, increasing to 16896MB
>>>> [ 0.009708] Faking node 0 at [mem 0x0000000000001000-0x0000000420000fff] (16896MB)
>>>> [ 0.009711] Faking node 1 at [mem 0x0000000420001000-0x000000083fffffff] (16895MB)
>>>> [ 0.009738] ------------[ cut here ]------------
>>>> [ 0.009739] -1 max nid when expected 1
>>>> [ 0.009760] WARNING: CPU: 0 PID: 0 at drivers/acpi/numa/srat.c:120 fix_pxm_node_maps+0x577/0x810
>>>> [ 0.009766] Modules linked in:
>>>> [ 0.009769] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.13.0-rc6+ #31
>>>> [ 0.009771] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
>>>> [ 0.009772] RIP: 0010:fix_pxm_node_maps+0x577/0x810
>>>> [ 0.009774] Code: 8b 85 40 ff ff ff 44 8b 8d 44 ff ff ff 8b 85 48 ff ff ff e9 83 fb ff ff 44 89 f2 44 89 ce 48 c7 c7 aa 2f 84 8d e8 b9 71 01 fe <0f> 0b 41 b8 ff ff ff ff e9 ba fb ff ff 48 c7 c7 a0 d8 d1 8d 44 89
>>>> [ 0.009776] RSP: 0000:ffffffff8da03be0 EFLAGS: 00010046 ORIG_RAX: 0000000000000000
>>>> [ 0.009778] RAX: 0000000000000000 RBX: 0000000000000400 RCX: 0000000000000000
>>>> [ 0.009779] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
>>>> [ 0.009780] RBP: ffffffff8da03ca8 R08: 0000000000000000 R09: 0000000000000000
>>>> [ 0.009781] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
>>>> [ 0.009782] R13: 00000000000007ff R14: 0000000000000001 R15: 0000000000000000
>>>> [ 0.009783] FS: 0000000000000000(0000) GS:ffffffff8de8c000(0000) knlGS:0000000000000000
>>>> [ 0.009784] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>>>> [ 0.009785] CR2: ffff90e4bde01000 CR3: 00000001bd03e000 CR4: 00000000000200b0
>>>> [ 0.009788] Call Trace:
>>>> [ 0.009790] <TASK>
>>>> [ 0.009792] ? show_regs+0x71/0x90
>>>> [ 0.009797] ? __warn+0x8d/0x150
>>>> [ 0.009799] ? fix_pxm_node_maps+0x577/0x810
>>>> [ 0.009802] ? report_bug+0x1ab/0x1c0
>>>> [ 0.009805] ? fixup_exception+0x27/0x380
>>>> [ 0.009809] ? early_fixup_exception+0xa2/0xf0
>>>> [ 0.009813] ? do_early_exception+0x28/0x90
>>>> [ 0.009816] ? early_idt_handler_common+0x2f/0x3a
>>>> [ 0.009819] ? fix_pxm_node_maps+0x577/0x810
>>>> [ 0.009822] ? numa_cleanup_meminfo+0x8c/0x5b0
>>>> [ 0.009828] numa_emulation+0x4e3/0xad0
>>>> [ 0.009830] ? __pfx_dummy_numa_init+0x10/0x10
>>>> [ 0.009833] ? __pfx_dummy_numa_init+0x10/0x10
>>>> [ 0.009836] numa_memblks_init+0x10c/0x2c0
>>>> [ 0.009838] ? __pfx_dummy_numa_init+0x10/0x10
>>>> [ 0.009840] numa_init+0x61/0x3e0
>>>> [ 0.009842] ? topology_register_boot_apic+0x2a/0x40
>>>> [ 0.009846] x86_numa_init+0x65/0x80
>>>> [ 0.009848] initmem_init+0xe/0x20
>>>> [ 0.009850] setup_arch+0x9d8/0xfa0
>>>> [ 0.009852] ? _printk+0x58/0x90
>>>> [ 0.009855] start_kernel+0x5f/0xb50
>>>> [ 0.009860] x86_64_start_reservations+0x18/0x30
>>>> [ 0.009863] x86_64_start_kernel+0xc0/0x110
>>>> [ 0.009864] ? setup_ghcb+0xe/0x140
>>>> [ 0.009867] common_startup_64+0x13e/0x141
>>>> [ 0.009871] </TASK>
>>>> [ 0.009871] ---[ end trace 0000000000000000 ]---
>>>>
>>>> [Git bisect log]
>>>>
>>>> # bad: [f378252a2168c2fbf8fc08b635061e5f6748c1f2] kasan: sw_tags: use str_on_off() helper in kasan_init_sw_tags()
>>>> git bisect bad f378252a2168c2fbf8fc08b635061e5f6748c1f2
>>>> # good: [cbc5dde0a461240046e8a41c43d7c3b76d5db952] fs/proc: fix softlockup in __read_vmcore (part 2)
>>>> git bisect good cbc5dde0a461240046e8a41c43d7c3b76d5db952
>>>> # good: [fb73203263021f2ee9dd54d280b1c543d10acd76] mm: move common part of pagetable_*_ctor to helper
>>>> git bisect good fb73203263021f2ee9dd54d280b1c543d10acd76
>>>> # bad: [8fd966c9310f14d5bbe653cf087853582170aad6] mm, swap: remove old allocation path for HDD
>>>> git bisect bad 8fd966c9310f14d5bbe653cf087853582170aad6
>>>> # bad: [8646971f02651146554233d63fdd721f5f060973] mm: shmem: skip swapcache for swapin of synchronous swap device
>>>> git bisect bad 8646971f02651146554233d63fdd721f5f060973
>>>> # good: [b8ba614eaa8dd31702c61e7df7231b1b18b99259] mm/damon/paddr: report filter-passed bytes back for DAMOS_STAT action
>>>> git bisect good b8ba614eaa8dd31702c61e7df7231b1b18b99259
>>>> # good: [fd0935b8e9e8c2edf05a3d0ffa09d0aa3e9cf2dd] Docs/ABI/damon: document per-region DAMOS filter-passed bytes stat file
>>>> git bisect good fd0935b8e9e8c2edf05a3d0ffa09d0aa3e9cf2dd
>>>> # good: [3ffd3cd7e2e8793d3b5fbb83c03668c47ab6d599] selftests/damon: remove tests for DAMON debugfs interface
>>>> git bisect good 3ffd3cd7e2e8793d3b5fbb83c03668c47ab6d599
>>>> # good: [bf9f93f0b7bff8af780330f5094775a39caf3612] mm/damon: remove DAMON debugfs interface
>>>> git bisect good bf9f93f0b7bff8af780330f5094775a39caf3612
>>>> # bad: [1746744be6ff271e29345a5be4cc144aa33b10ab] mm/memmap: prevent double scanning of memmap by kmemleak
>>>> git bisect bad 1746744be6ff271e29345a5be4cc144aa33b10ab
>>>> # bad: [ca19a5ab8756ef78c34d02d2b8c266a9cc7bf57d] mm/fake-numa: allow later numa node hotplug
>>>> git bisect bad ca19a5ab8756ef78c34d02d2b8c266a9cc7bf57d
>>>> # first bad commit: [ca19a5ab8756ef78c34d02d2b8c266a9cc7bf57d] mm/fake-numa: allow later numa node hotplug
>>>>
>>>>> ---
>>>>> drivers/acpi/numa/srat.c | 86 ++++++++++++++++++++++++++++++++++++
>>>>> include/acpi/acpi_numa.h | 5 +++
>>>>> include/linux/numa_memblks.h | 3 ++
>>>>> mm/numa_emulation.c | 45 ++++++++++++++++---
>>>>> mm/numa_memblks.c | 2 +-
>>>>> 5 files changed, 133 insertions(+), 8 deletions(-)
>>>>>
>>>>> diff --git a/drivers/acpi/numa/srat.c b/drivers/acpi/numa/srat.c
>>>>> index bec0dcd1f9c3..59fffe34c9d0 100644
>>>>> --- a/drivers/acpi/numa/srat.c
>>>>> +++ b/drivers/acpi/numa/srat.c
>>>>> @@ -81,6 +81,92 @@ int acpi_map_pxm_to_node(int pxm)
>>>>> }
>>>>> EXPORT_SYMBOL(acpi_map_pxm_to_node);
>>>>> +#ifdef CONFIG_NUMA_EMU
>>>>> +/*
>>>>> + * Take max_nid - 1 fake-numa nodes into account in both
>>>>> + * pxm_to_node_map()/node_to_pxm_map[] tables.
>>>>> + */
>>>>> +int __init fix_pxm_node_maps(int max_nid)
>>>>> +{
>>>>> + static int pxm_to_node_map_copy[MAX_PXM_DOMAINS] __initdata
>>>>> + = { [0 ... MAX_PXM_DOMAINS - 1] = NUMA_NO_NODE };
>>>>> + static int node_to_pxm_map_copy[MAX_NUMNODES] __initdata
>>>>> + = { [0 ... MAX_NUMNODES - 1] = PXM_INVAL };
>>>>> + int i, j, index = -1, count = 0;
>>>>> + nodemask_t nodes_to_enable;
>>>>> +
>>>>> + if (numa_off || srat_disabled())
>>>>> + return -1;
>>>>> +
>>>>> + /* find fake nodes PXM mapping */
>>>>> + for (i = 0; i < MAX_NUMNODES; i++) {
>>>>> + if (node_to_pxm_map[i] != PXM_INVAL) {
>>>>> + for (j = 0; j <= max_nid; j++) {
>>>>> + if ((emu_nid_to_phys[j] == i) &&
>>>>> + WARN(node_to_pxm_map_copy[j] != PXM_INVAL,
>>>>> + "Node %d is already binded to PXM %d\n",
>>>>> + j, node_to_pxm_map_copy[j]))
>>>>> + return -1;
>>>>> + if (emu_nid_to_phys[j] == i) {
>>>>> + node_to_pxm_map_copy[j] =
>>>>> + node_to_pxm_map[i];
>>>>> + if (j > index)
>>>>> + index = j;
>>>>> + count++;
>>>>> + }
>>>>> + }
>>>>> + }
>>>>> + }
>>>>> + if (WARN(index != max_nid, "%d max nid when expected %d\n",
>>>>> + index, max_nid))
>>>>> + return -1;
>>>>> +
>>>>> + nodes_clear(nodes_to_enable);
>>>>> +
>>>>> + /* map phys nodes not used for fake nodes */
>>>>> + for (i = 0; i < MAX_NUMNODES; i++) {
>>>>> + if (node_to_pxm_map[i] != PXM_INVAL) {
>>>>> + for (j = 0; j <= max_nid; j++)
>>>>> + if (emu_nid_to_phys[j] == i)
>>>>> + break;
>>>>> + /* fake nodes PXM mapping has been done */
>>>>> + if (j <= max_nid)
>>>>> + continue;
>>>>> + /* find first hole */
>>>>> + for (j = 0;
>>>>> + j < MAX_NUMNODES &&
>>>>> + node_to_pxm_map_copy[j] != PXM_INVAL;
>>>>> + j++)
>>>>> + ;
>>>>> + if (WARN(j == MAX_NUMNODES,
>>>>> + "Number of nodes exceeds MAX_NUMNODES\n"))
>>>>> + return -1;
>>>>> + node_to_pxm_map_copy[j] = node_to_pxm_map[i];
>>>>> + node_set(j, nodes_to_enable);
>>>>> + count++;
>>>>> + }
>>>>> + }
>>>>> +
>>>>> + /* creating reverse mapping in pxm_to_node_map[] */
>>>>> + for (i = 0; i < MAX_NUMNODES; i++)
>>>>> + if (node_to_pxm_map_copy[i] != PXM_INVAL &&
>>>>> + pxm_to_node_map_copy[node_to_pxm_map_copy[i]] == NUMA_NO_NODE)
>>>>> + pxm_to_node_map_copy[node_to_pxm_map_copy[i]] = i;
>>>>> +
>>>>> + /* overwrite with new mapping */
>>>>> + for (i = 0; i < MAX_NUMNODES; i++) {
>>>>> + node_to_pxm_map[i] = node_to_pxm_map_copy[i];
>>>>> + pxm_to_node_map[i] = pxm_to_node_map_copy[i];
>>>>> + }
>>>>> +
>>>>> + /* enable other nodes found in PXM for hotplug */
>>>>> + nodes_or(numa_nodes_parsed, nodes_to_enable, numa_nodes_parsed);
>>>>> +
>>>>> + pr_debug("found %d total number of nodes\n", count);
>>>>> + return 0;
>>>>> +}
>>>>> +#endif
>>>>> +
>>>>> static void __init
>>>>> acpi_table_print_srat_entry(struct acpi_subtable_header *header)
>>>>> {
>>>>> diff --git a/include/acpi/acpi_numa.h b/include/acpi/acpi_numa.h
>>>>> index b5f594754a9e..99b960bd473c 100644
>>>>> --- a/include/acpi/acpi_numa.h
>>>>> +++ b/include/acpi/acpi_numa.h
>>>>> @@ -17,11 +17,16 @@ extern int node_to_pxm(int);
>>>>> extern int acpi_map_pxm_to_node(int);
>>>>> extern unsigned char acpi_srat_revision;
>>>>> extern void disable_srat(void);
>>>>> +extern int fix_pxm_node_maps(int max_nid);
>>>>> extern void bad_srat(void);
>>>>> extern int srat_disabled(void);
>>>>> #else /* CONFIG_ACPI_NUMA */
>>>>> +static inline int fix_pxm_node_maps(int max_nid)
>>>>> +{
>>>>> + return 0;
>>>>> +}
>>>>> static inline void disable_srat(void)
>>>>> {
>>>>> }
>>>>> diff --git a/include/linux/numa_memblks.h b/include/linux/numa_memblks.h
>>>>> index cfad6ce7e1bd..dd85613cdd86 100644
>>>>> --- a/include/linux/numa_memblks.h
>>>>> +++ b/include/linux/numa_memblks.h
>>>>> @@ -29,7 +29,10 @@ int __init numa_cleanup_meminfo(struct numa_meminfo *mi);
>>>>> int __init numa_memblks_init(int (*init_func)(void),
>>>>> bool memblock_force_top_down);
>>>>> +extern int numa_distance_cnt;
>>>>> +
>>>>> #ifdef CONFIG_NUMA_EMU
>>>>> +extern int emu_nid_to_phys[MAX_NUMNODES];
>>>>> int numa_emu_cmdline(char *str);
>>>>> void __init numa_emu_update_cpu_to_node(int *emu_nid_to_phys,
>>>>> unsigned int nr_emu_nids);
>>>>> diff --git a/mm/numa_emulation.c b/mm/numa_emulation.c
>>>>> index 031fb9961bf7..9d55679d99ce 100644
>>>>> --- a/mm/numa_emulation.c
>>>>> +++ b/mm/numa_emulation.c
>>>>> @@ -8,11 +8,12 @@
>>>>> #include <linux/memblock.h>
>>>>> #include <linux/numa_memblks.h>
>>>>> #include <asm/numa.h>
>>>>> +#include <acpi/acpi_numa.h>
>>>>> #define FAKE_NODE_MIN_SIZE ((u64)32 << 20)
>>>>> #define FAKE_NODE_MIN_HASH_MASK (~(FAKE_NODE_MIN_SIZE - 1UL))
>>>>> -static int emu_nid_to_phys[MAX_NUMNODES];
>>>>> +int emu_nid_to_phys[MAX_NUMNODES];
>>>>> static char *emu_cmdline __initdata;
>>>>> int __init numa_emu_cmdline(char *str)
>>>>> @@ -379,6 +380,7 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
>>>>> size_t phys_size = numa_dist_cnt * numa_dist_cnt * sizeof(phys_dist[0]);
>>>>> int max_emu_nid, dfl_phys_nid;
>>>>> int i, j, ret;
>>>>> + nodemask_t physnode_mask = numa_nodes_parsed;
>>>>> if (!emu_cmdline)
>>>>> goto no_emu;
>>>>> @@ -395,7 +397,6 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
>>>>> * split the system RAM into N fake nodes.
>>>>> */
>>>>> if (strchr(emu_cmdline, 'U')) {
>>>>> - nodemask_t physnode_mask = numa_nodes_parsed;
>>>>> unsigned long n;
>>>>> int nid = 0;
>>>>> @@ -465,9 +466,6 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
>>>>> */
>>>>> max_emu_nid = setup_emu2phys_nid(&dfl_phys_nid);
>>>>> - /* commit */
>>>>> - *numa_meminfo = ei;
>>>>> -
>>>>> /* Make sure numa_nodes_parsed only contains emulated nodes */
>>>>> nodes_clear(numa_nodes_parsed);
>>>>> for (i = 0; i < ARRAY_SIZE(ei.blk); i++)
>>>>> @@ -475,10 +473,21 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
>>>>> ei.blk[i].nid != NUMA_NO_NODE)
>>>>> node_set(ei.blk[i].nid, numa_nodes_parsed);
>>>>> - numa_emu_update_cpu_to_node(emu_nid_to_phys, ARRAY_SIZE(emu_nid_to_phys));
>>>>> + /* fix pxm_to_node_map[] and node_to_pxm_map[] to avoid collision
>>>>> + * with faked numa nodes, particularly during later memory hotplug
>>>>> + * handling, and also update numa_nodes_parsed accordingly.
>>>>> + */
>>>>> + ret = fix_pxm_node_maps(max_emu_nid);
>>>>> + if (ret < 0)
>>>>> + goto no_emu;
>>>>> +
>>>>> + /* commit */
>>>>> + *numa_meminfo = ei;
>>>>> +
>>>>> + numa_emu_update_cpu_to_node(emu_nid_to_phys, max_emu_nid + 1);
>>>>> /* make sure all emulated nodes are mapped to a physical node */
>>>>> - for (i = 0; i < ARRAY_SIZE(emu_nid_to_phys); i++)
>>>>> + for (i = 0; i < max_emu_nid + 1; i++)
>>>>> if (emu_nid_to_phys[i] == NUMA_NO_NODE)
>>>>> emu_nid_to_phys[i] = dfl_phys_nid;
>>>>> @@ -501,12 +510,34 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
>>>>> numa_set_distance(i, j, dist);
>>>>> }
>>>>> }
>>>>> + for (i = 0; i < numa_distance_cnt; i++) {
>>>>> + for (j = 0; j < numa_distance_cnt; j++) {
>>>>> + int physi, physj;
>>>>> + u8 dist;
>>>>> +
>>>>> + /* distance between fake nodes is already ok */
>>>>> + if (emu_nid_to_phys[i] != NUMA_NO_NODE &&
>>>>> + emu_nid_to_phys[j] != NUMA_NO_NODE)
>>>>> + continue;
>>>>> + if (emu_nid_to_phys[i] != NUMA_NO_NODE)
>>>>> + physi = emu_nid_to_phys[i];
>>>>> + else
>>>>> + physi = i - max_emu_nid;
>>>>> + if (emu_nid_to_phys[j] != NUMA_NO_NODE)
>>>>> + physj = emu_nid_to_phys[j];
>>>>> + else
>>>>> + physj = j - max_emu_nid;
>>>>> + dist = phys_dist[physi * numa_dist_cnt + physj];
>>>>> + numa_set_distance(i, j, dist);
>>>>> + }
>>>>> + }
>>>>> /* free the copied physical distance table */
>>>>> memblock_free(phys_dist, phys_size);
>>>>> return;
>>>>> no_emu:
>>>>> + numa_nodes_parsed = physnode_mask;
>>>>> /* No emulation. Build identity emu_nid_to_phys[] for numa_add_cpu() */
>>>>> for (i = 0; i < ARRAY_SIZE(emu_nid_to_phys); i++)
>>>>> emu_nid_to_phys[i] = i;
>>>>> diff --git a/mm/numa_memblks.c b/mm/numa_memblks.c
>>>>> index a3877e9bc878..ff4054f4334d 100644
>>>>> --- a/mm/numa_memblks.c
>>>>> +++ b/mm/numa_memblks.c
>>>>> @@ -7,7 +7,7 @@
>>>>> #include <linux/numa.h>
>>>>> #include <linux/numa_memblks.h>
>>>>> -static int numa_distance_cnt;
>>>>> +int numa_distance_cnt;
>>>>> static u8 *numa_distance;
>>>>> nodemask_t numa_nodes_parsed __initdata;
>>>
>>>
>>> Best Regards,
>>> Yan, Zi
>>>
>
>
>
>