dhclient.lease我在我的 RHEL7.4 上找不到任何东西。里面没有人/var/lib/dhclient。
我的 RHEL7 上的输出lsof显示一个带有文件描述符的文件mem被 40 个进程使用。这是否意味着该文件在内存中映射了 40 次或什么？有人可以解释一下内存映射文件是什么意思吗？这是否意味着它在我的记忆中出现了 40 次？
# lsof /usr/lib/locale/locale-archive 命令 PID 用户 FD 类型 设备尺寸/关闭节点名称 vmtoolsd 605 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive agetty 656 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive 调谐 963 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive iostat 1199 adm mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive chkMtaMem 1205 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive snmpd 4704 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive 睡眠 5461 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive cmsubagt 6487 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive 睡眠 6649 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc1 6803 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc2 6835 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc3 6836 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc4 6856 root mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc5 6884 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc6 6889 usr mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc7 6893 usr1 mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive cmfpagt 7704 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc8 7943 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive crond 8001 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive sh 8005 adm mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive iostat 8014 adm mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive crond 20427 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc9 20648 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc10 20649 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc10 20760 usr2 mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc9 20777 usr2 mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc11 21353 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc12 21354 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc13 21355 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc14 21356 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc15 21357 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc16 21358 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc17 21554 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc18 21569 usr2 mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc19 21590 usr2 mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc20 21647 usr2 mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc21 22016 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc22 22017 根内存 REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc23 22104 usr2 mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive proc24 22122 usr2 mem REG 8,5 106070960 50808629 /usr/lib/locale/locale-archive
我的 RHEL7 系统出现“页面分配失败”错误。这里是：
内核：[85531.010995] sh：页面分配失败：顺序：4，模式：0x2040d0 内核：[85531.011000] CPU：1 PID：20846 通信：sh 未污染 3.10.0-693.el7.AV1.x86_64 #1 内核：[85531.011002] 硬件名称：VMware, Inc. VMware Virtual Platform/440BX 桌面参考平台，BIOS 6.00 09/21/2015 内核：[85531.011003] 00000000002040d0 00000000d00413f4 ffff8800070ffa18 ffffffff816a3e1d 内核：[85531.011006] ffff8800070ffaa8 ffffffff81188d00 0000000000000000 ffff88023ffd8000 内核：[85531.011008] 0000000000000004 00000000002040d0 ffff8800070ffaa8 00000000d00413f4 内核：[85531.011010] 调用跟踪： 内核：[85531.011018] [] dump_stack+0x19/0x1b 内核：[85531.011023] [] warn_alloc_failed+0x110/0x180 内核：[85531.011026] [] __alloc_pages_slowpath+0x6b6/0x724 内核：[85531.011028] [] __alloc_pages_nodemask+0x405/0x420 内核：[85531.011031] [] alloc_pages_current+0x98/0x110 内核：[85531.011035] [] new_slab+0x2fc/0x310 内核：[85531.011037] [] ___slab_alloc+0x3ac/0x4f0 内核：[85531.011042] []？复制进程+0x18e/0x19a0 内核：[85531.011044] []？复制进程+0x18e/0x19a0 内核：[85531.011046] [] __slab_alloc+0x40/0x5c 内核：[85531.011049] [] kmem_cache_alloc_node+0x8b/0x200 内核：[85531.011051] [] copy_process+0x18e/0x19a0 内核：[85531.011053] [] do_fork+0x91/0x320 内核：[85531.011056] [] SyS_clone+0x16/0x20 内核：[85531.011059] [] stub_clone+0x69/0x90 内核：[85531.011061] []？system_call_fastpath+0x16/0x1b 内核：[85531.011062] 内存信息： 内核：[85531.011066] active_anon:1145227 inactive_anon:278512 isolated_anon:0 内核：[85531.011066] active_file:181319 inactive_file:185784 isolated_file:0 内核：[85531.011066] unevictable：2695 脏：4333 写回：0 不稳定：0 内核：[85531.011066]slab_reclaimable:45889slab_unreclaimable:54798 内核：[85531.011066] 映射：79471 shmem：52418 页表：11994 反弹：0 内核：[85531.011066] free:33850 free_pcp:0 free_cma:0 内核：[85531.011069] Node 0 DMA free:15868kB min:132kB low:164kB high:196kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15992kB托管：15908kB mlocked：0kB 脏：0kB 写回：0kB 映射：0kB shmem：0kB slab_reclaimable：0kB slab_unreclaimable：8kB kernel_stack：0kB pagetables：0kB 不稳定：0kB 反弹：0kB free_pcp：0kB local_pcp：0kB free_cma：0kB writeback_tmp：0kB pages_scanned： 0 all_unreclaimable？是的 内核：[85531.011073] lowmem_reserve[]：0 2809 7800 7800 kernel: [85531.011076] Node 0 DMA32 free:53892kB min:24292kB low:30364kB high:36436kB active_anon:1622080kB inactive_anon:516652kB active_file:203244kB inactive_file:212104kB unevictable:2312kB isolated(anon):0kB isolated(file):0kB present:3129280kB managed:2878656kB mlocked:2312kB dirty:6236kB writeback:0kB mapped:115972kB shmem:79808kB slab_reclaimable:77740kB slab_unreclaimable:90500kB kernel_stack:13680kB pagetables:17624kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned: 0 all_unreclaimable？不 内核：[85531.011080] lowmem_reserve[]：0 0 4990 4990 内核：[85531.011082] 节点 0 正常空闲：65640kB 最小值：43152kB 低：53940kB 高：64728kB active_anon:2958828kB inactive_anon:597396kB active_file:522032kB inactive_file:531032kB unvictable:8468kB 已隔离（kB 已隔离：531032kB managed:5110372kB mlocked:8464kB dirty:11096kB writeback:0kB mapped:201912kB shmem:129864kB slab_reclaimable:105816kB slab_unreclaimable:128684kB kernel_stack:19936kB pagetables:30352kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned: 0 all_unreclaimable？不 内核：[85531.011085] lowmem_reserve[]：0 0 0 0 内核：[85531.011087] 节点 0 DMA：1*4kB (U) 1*8kB (U) 1*16kB (U) 1*32kB (U) 1*64kB (U) 1*128kB (U) 1*256kB (U ) 0*512kB 1*1024kB (U) 1*2048kB (M) 3*4096kB (M) = 15868kB 内核：[85531.011095] 节点 0 DMA32：2946*4kB (UEM) 1995*8kB (UEM) 1241*16kB (UEM) 186*32kB (UEM) 9*64kB (U) 0*128kB 0*256kB 0*512kB 0* 1024kB 0*2048kB 0*4096kB = 54128kB 内核：[85531.011102] 节点 0 正常：16005*4kB (UEM) 248*8kB (UEM) 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 66004k 内核：[85531.011108] 节点 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB 内核：[85531.011109] 428930 总页面缓存页面 内核：[85531.011110] 交换缓存中有 8261 个页面 内核：[85531.011111]交换缓存统计：添加51264，删除43003，查找2892763/2894481 内核：[85531.011112] 自由交换 = 5078128kB 内核：[85531.011113] 总交换 = 5242876kB 内核：[85531.011114] 2097038 页 RAM 内核：[85531.011114] 0 页 HighMem/MovableOnly 内核：[85531.011115] 95804 页保留 内核：[85531.011116] SLUB：无法在节点 -1 上分配内存（gfp=0xd0） 内核：[85531.011118] 缓存：task_struct，对象大小：45024，缓冲区大小：45024，默认顺序：4，最小顺序：4 内核：[85531.011119] 节点 0：slabs：2114，objs：2114，免费：0
问题是关于其消息的最新部分：
内核：[85531.011116] SLUB：无法在节点 -1 上分配内存（gfp=0xd0） 内核：[85531.011118] 缓存：task_struct，对象大小：45024，缓冲区大小：45024，默认顺序：4，最小顺序：4 内核：[85531.011119] 节点 0：slabs：2114，objs：2114，免费：0
-1当 Zone from 分配失败时，为什么节点索引有Node 0？这有点混乱。。
内核：[85531.011087] 节点 0 DMA：1*4kB (U) 1*8kB (U) 1*16kB (U) 1*32kB (U) 1*64kB (U) 1*128kB (U) 1*256kB (U ) 0*512kB 1*1024kB (U) 1*2048kB (M) 3*4096kB (M) = 15868kB 内核：[85531.011095] 节点 0 DMA32：2946*4kB (UEM) 1995*8kB (UEM) 1241*16kB (UEM) 186*32kB (UEM) 9*64kB (U) 0*128kB 0*256kB 0*512kB 0* 1024kB 0*2048kB 0*4096kB = 54128kB 内核：[85531.011102] 节点 0 正常：16005*4kB (UEM) 248*8kB (UEM) 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 66004k
有没有办法跟踪内核执行的内存分配？我找到了一篇文章，其中在内核日志中跟踪内存分配（我猜）。这是它的样子：
[ 3830.215613] [HIGHERORDER_DEBUG] : __alloc_pages_nodemask is called by process <PID = 1168, NAME = Xorg> !!!
也许它是一些自定义内核构建......
有没有办法以这种方式跟踪内存分配？也许有一些工具可以做到这一点？我正在使用 RHEL7。
我有一个长期工作的服务器应用程序，它应该可以无故障运行数月。将设备移至 RHEL7 后，系统在正常负载约 2-3 天后开始出现内存碎片。有很多来自内核的“页面分配失败”消息，表明无法为几乎每个进程分配正常区域中的 4 个有序页面（虽然有很多低序页面）。这是一个例子：
kernel: [85531.010995] sh: page allocation failure: order:4, mode:0x2040d0
kernel: [85531.011000] CPU: 1 PID: 20846 Comm: sh Not tainted 3.10.0-693.el7.AV1.x86_64 #1
kernel: [85531.011002] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 09/21/2015
kernel: [85531.011003] 00000000002040d0 00000000d00413f4 ffff8800070ffa18 ffffffff816a3e1d
kernel: [85531.011006] ffff8800070ffaa8 ffffffff81188d00 0000000000000000 ffff88023ffd8000
kernel: [85531.011008] 0000000000000004 00000000002040d0 ffff8800070ffaa8 00000000d00413f4
kernel: [85531.011010] Call Trace:
kernel: [85531.011018] [<ffffffff816a3e1d>] dump_stack+0x19/0x1b
kernel: [85531.011023] [<ffffffff81188d00>] warn_alloc_failed+0x110/0x180
kernel: [85531.011026] [<ffffffff8169fe1a>] __alloc_pages_slowpath+0x6b6/0x724
kernel: [85531.011028] [<ffffffff8118d275>] __alloc_pages_nodemask+0x405/0x420
kernel: [85531.011031] [<ffffffff811d15f8>] alloc_pages_current+0x98/0x110
kernel: [85531.011035] [<ffffffff811dc36c>] new_slab+0x2fc/0x310
kernel: [85531.011037] [<ffffffff811ddbfc>] ___slab_alloc+0x3ac/0x4f0
kernel: [85531.011042] [<ffffffff810850be>] ? copy_process+0x18e/0x19a0
kernel: [85531.011044] [<ffffffff810850be>] ? copy_process+0x18e/0x19a0
kernel: [85531.011046] [<ffffffff816a117e>] __slab_alloc+0x40/0x5c
kernel: [85531.011049] [<ffffffff811e00cb>] kmem_cache_alloc_node+0x8b/0x200
kernel: [85531.011051] [<ffffffff810850be>] copy_process+0x18e/0x19a0
kernel: [85531.011053] [<ffffffff81086a81>] do_fork+0x91/0x320
kernel: [85531.011056] [<ffffffff81086d96>] SyS_clone+0x16/0x20
kernel: [85531.011059] [<ffffffff816b5259>] stub_clone+0x69/0x90
kernel: [85531.011061] [<ffffffff816b4f09>] ? system_call_fastpath+0x16/0x1b
kernel: [85531.011062] Mem-Info:
kernel: [85531.011066] active_anon:1145227 inactive_anon:278512 isolated_anon:0
kernel: [85531.011066] active_file:181319 inactive_file:185784 isolated_file:0
kernel: [85531.011066] unevictable:2695 dirty:4333 writeback:0 unstable:0
kernel: [85531.011066] slab_reclaimable:45889 slab_unreclaimable:54798
kernel: [85531.011066] mapped:79471 shmem:52418 pagetables:11994 bounce:0
kernel: [85531.011066] free:33850 free_pcp:0 free_cma:0
kernel: [85531.011069] Node 0 DMA free:15868kB min:132kB low:164kB high:196kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15992kB managed:15908kB mlocked:0kB dirty:0kB writeback:0kB mapped:0kB shmem:0kB slab_reclaimable:0kB slab_unreclaimable:8kB kernel_stack:0kB pagetables:0kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? yes
kernel: [85531.011073] lowmem_reserve[]: 0 2809 7800 7800
kernel: [85531.011076] Node 0 DMA32 free:53892kB min:24292kB low:30364kB high:36436kB active_anon:1622080kB inactive_anon:516652kB active_file:203244kB inactive_file:212104kB unevictable:2312kB isolated(anon):0kB isolated(file):0kB present:3129280kB managed:2878656kB mlocked:2312kB dirty:6236kB writeback:0kB mapped:115972kB shmem:79808kB slab_reclaimable:77740kB slab_unreclaimable:90500kB kernel_stack:13680kB pagetables:17624kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no
kernel: [85531.011080] lowmem_reserve[]: 0 0 4990 4990
kernel: [85531.011082] Node 0 Normal free:65640kB min:43152kB low:53940kB high:64728kB active_anon:2958828kB inactive_anon:597396kB active_file:522032kB inactive_file:531032kB unevictable:8468kB isolated(anon):0kB isolated(file):0kB present:5242880kB managed:5110372kB mlocked:8464kB dirty:11096kB writeback:0kB mapped:201912kB shmem:129864kB slab_reclaimable:105816kB slab_unreclaimable:128684kB kernel_stack:19936kB pagetables:30352kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no
kernel: [85531.011085] lowmem_reserve[]: 0 0 0 0
kernel: [85531.011087] Node 0 DMA: 1*4kB (U) 1*8kB (U) 1*16kB (U) 1*32kB (U) 1*64kB (U) 1*128kB (U) 1*256kB (U) 0*512kB 1*1024kB (U) 1*2048kB (M) 3*4096kB (M) = 15868kB
kernel: [85531.011095] Node 0 DMA32: 2946*4kB (UEM) 1995*8kB (UEM) 1241*16kB (UEM) 186*32kB (UEM) 9*64kB (U) 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 54128kB
kernel: [85531.011102] Node 0 Normal: 16005*4kB (UEM) 248*8kB (UEM) 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 66004kB
kernel: [85531.011108] Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB
kernel: [85531.011109] 428930 total pagecache pages
kernel: [85531.011110] 8261 pages in swap cache
kernel: [85531.011111] Swap cache stats: add 51264, delete 43003, find 2892763/2894481
kernel: [85531.011112] Free swap = 5078128kB
kernel: [85531.011113] Total swap = 5242876kB
kernel: [85531.011114] 2097038 pages RAM
kernel: [85531.011114] 0 pages HighMem/MovableOnly
kernel: [85531.011115] 95804 pages reserved
kernel: [85531.011116] SLUB: Unable to allocate memory on node -1 (gfp=0xd0)
kernel: [85531.011118] cache: task_struct, object size: 45024, buffer size: 45024, default order: 4, min order: 4
kernel: [85531.011119] node 0: slabs: 2114, objs: 2114, free: 0
因此，我有一些问题：
- 什么会影响系统上的内存碎片？
- 是否可以确定是什么进程导致了碎片（例如，哪个进程最常使用 4 个订单页面）？
- 而且，当然，如何调整系统以避免内存碎片？
升级版：
- 我发现该
CONFIG_COMPACTION选项对我的情况有帮助，但找不到如何启用它或检查其当前状态。那么，我该如何检查/启用它？
之前在 RHEL6 和 RHEL5 上一切正常。
# uname -a
Linux <hostname> 3.10.0-693.21.1.el7.AV1.x86_64 #1 SMP Thursday April 5, 2018 09:26:08 MDT x86_64 x86_64 x86_64 GNU/Linux
那是在 ESXi 6.5 上运行的虚拟机
UPD1：系统现在再次缺少订单 4 页。内核消息显示，在分配时，DMA32 区域中有足够的页面，但正常区域为 0。
[82794.805373] Node 0 DMA: 1*4kB (U) 0*8kB 1*16kB (U) 1*32kB (U) 1*64kB (U) 1*128kB (U) 1*256kB (U) 0*512kB 1*1024kB (U) 1*2048kB (M) 3*4096kB (M) = 15860kB
[82794.805384] Node 0 DMA32: 4528*4kB (UEM) 2604*8kB (UEM) 1544*16kB (UEM) 142*32kB (UE) 19*64kB (EM) 3*128kB (U) 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 69792kB
[82794.805393] Node 0 Normal: 17041*4kB (UEM) 183*8kB (UEM) 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 69628kB
是否有可能以某种方式在 DMA32 中进行系统分配？我不是该领域的专家，因此感谢您提供任何信息。
UPD2我尝试过使用内核参数，例如
vm.swappiness，vm.dirty_ratio但它只是推迟了故障的发生。此外，增加内存量也无济于事。
UPD3删除内核缓存
echo 3 > /proc/sys/vm/drop_caches有助于暂时避免“页面分配失败”。但我知道这不是一个永久的解决方案，因为它会影响性能。
我已安装最新的英特尔微码更新以使用 Spectre 变体 #2 修复，但Spectre&Meltdown 检查器仍显示无法使用 IBRS/IBPB。
CVE-2017-5715 [branch target injection] aka 'Spectre Variant 2'
* Mitigation 1
* Kernel is compiled with IBRS/IBPB support: YES
* Currently enabled features
* IBRS enabled for Kernel space: NO
* IBRS enabled for User space: NO
* IBPB enabled: NO
* Mitigation 2
* Kernel has branch predictor hardening (arm): NO
* Kernel compiled with retpoline option: NO
* Kernel compiled with a retpoline-aware compiler: NO
> STATUS: VULNERABLE (Your kernel is compiled with IBRS but your CPU microcode is lacking support to successfully mitigate the vulnerability)
dmesg 显示已安装最新版本。
# dmesg | grep microcode
[ 1.199842] microcode: CPU0 sig=0x206d7, pf=0x1, revision=0x713
[ 1.199860] microcode: CPU1 sig=0x206d7, pf=0x1, revision=0x713
[ 1.199877] microcode: CPU2 sig=0x206d7, pf=0x1, revision=0x713
[ 1.199898] microcode: CPU3 sig=0x206d7, pf=0x1, revision=0x713
[ 1.199966] microcode: Microcode Update Driver: v2.01 <[email protected]>, Peter Oruba
CPU 是Intel(R) Xeon(R) CPU E5-2420 0 @ 1.90GHz，主机类型是ESXi-5.1.0-20130402001-standard
尝试使用以下过程将 Intel 微码更新到 03/12/2018 版本（版本：20180312）：
1. extract files from downloaded tarball
2. cp -v intel-ucode/* /lib/firmware/intel-ucode/
3. echo 1 > /sys/devices/system/cpu/microcode/reload
4. dracut -vvf
5. reboot
但没有任何改变。更新前：
# cat /proc/cpuinfo | grep microcode
microcode : 0x13
更新后：
# dmesg | grep microcode
[ 1.096790] microcode: CPU0 sig=0x206c2, pf=0x1, revision=0x13
[ 1.096829] microcode: CPU1 sig=0x206c2, pf=0x1, revision=0x13
[ 1.096851] microcode: CPU2 sig=0x206c2, pf=0x1, revision=0x13
[ 1.096875] microcode: CPU3 sig=0x206c2, pf=0x1, revision=0x13
[ 1.096965] microcode: Microcode Update Driver: v2.01 <[email protected]>, Peter Oruba
我这样做是为了修复“幽灵变体 2”。spectre-meltdown-checker.sh 显示以下内容：
CVE-2017-5715 [branch target injection] aka 'Spectre Variant 2'
* Mitigation 1
* Kernel is compiled with IBRS/IBPB support: YES
* Currently enabled features
* IBRS enabled for Kernel space: NO
* IBRS enabled for User space: NO
* IBPB enabled: NO
* Mitigation 2
* Kernel has branch predictor hardening (arm): NO
* Kernel compiled with retpoline option: NO
* Kernel compiled with a retpoline-aware compiler: NO
> STATUS: VULNERABLE (Your kernel is compiled with IBRS but your CPU microcode is lacking support to successfully mitigate the vulnerability)
CPU 如下： Intel(R) Xeon(R) CPU E5620 @ 2.40GHz