{"id":551,"date":"2014-09-17T21:54:44","date_gmt":"2014-09-17T13:54:44","guid":{"rendered":"http:\/\/blog.sorayuki.net\/?p=551"},"modified":"2014-09-18T00:40:10","modified_gmt":"2014-09-17T16:40:10","slug":"x86%e9%80%bb%e8%be%91%e5%9c%b0%e5%9d%80%e8%bd%ac%e7%89%a9%e7%90%86%e5%9c%b0%e5%9d%80%e5%ae%9e%e9%aa%8c","status":"publish","type":"post","link":"https:\/\/blog.sorayuki.net\/?p=551","title":{"rendered":"x86\u903b\u8f91\u5730\u5740\u8f6c\u7269\u7406\u5730\u5740\u5b9e\u9a8c"},"content":{"rendered":"<p>\u4e4b\u524d\u4e00\u7bc7\u6587\u7ae0\u5173\u4e8e\u5f80NetBSD\u6dfb\u52a0\u7cfb\u7edf\u8c03\u7528\uff0c\u662f\u4e3a\u4e86\u505a\u8fd9\u4e2a\u5b9e\u9a8c\u51c6\u5907\u7684\u3002<\/p>\n<p>\u60f3\u8981\u7814\u7a76x86\u67b6\u6784\u4e0b\u7684\u5185\u5b58\u7ba1\u7406\uff0c\u6700\u91cd\u8981\u7684\u53c2\u8003\u6587\u6863\u5e94\u8be5\u662f\u82f1\u7279\u5c14\u5b98\u65b9\u5173\u4e8e\u5185\u5b58\u7ba1\u7406\u65b9\u9762\u7684\u89e3\u91ca\u4e86\u3002\u5728 Intel? 64 and IA-32 Architectures Software Developer\u2019s Manual Volume 3A: System Programming Guide, Part 1 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href=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image1.png\"><img loading=\"lazy\" decoding=\"async\" style=\"display: inline;\" title=\"image\" src=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image_thumb1.png\" alt=\"image\" width=\"585\" height=\"507\" \/><\/a><br \/>\nIntel\u90a3\u4e2a\u6587\u6863\u91cc\u7684\u56fe\u7247\u5bf9\u4e8e\u6574\u4e2a\u5730\u5740\u7684\u8f6c\u8bd1\u8fc7\u7a0b\u8bf4\u5f97\u5f88\u6e05\u695a\uff0c\u914d\u4e0a\u56fe\u7247\u5c31\u66f4\u52a0\u5bb9\u6613\u7406\u89e3\u4e86\u3002\u8fd9\u5f20\u56fe\u7247\u7684\u5de6\u4e0a\u89d2\uff0c\u201c\u903b\u8f91\u5730\u5740\u201d\uff0c\u6216\u8005\u8bf4Far Pointer\uff0c\u5c31\u662f\u5e73\u65f6\u5199C\u8bed\u8a00\u7a0b\u5e8f\u7684\u65f6\u5019\u4f1a\u9047\u5230\u7684\u53eb\u201c\u6307\u9488\u201d\u7684\u4e1c\u897f\u3002<br 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ES\u8fd9\u4e9b\u662f\u6bb5\u5bc4\u5b58\u5668\uff0c\u91cc\u9762\u4fdd\u5b58\u4e86\u6bb5\u7684\u7f16\u53f7\u3002\u901a\u8fc7\u6bb5\u7684\u7f16\u53f7\u53ef\u4ee5\u5728\u6bb5\u8868\u4e2d\u627e\u5230\u8fd9\u4e2a\u6bb5\u7684\u4fe1\u606f\uff0c\u8fdb\u800c\u83b7\u53d6\u5230\u6bb5\u7684\u57fa\u5740\u3002\u4f46\u662f\u73b0\u5728\u7684\u64cd\u4f5c\u7cfb\u7edf\uff0c\u6bd4\u5982Windows\u3001Linux\u3001*BSD\u5565\u7684\uff0c\u5927\u90e8\u5206\u60c5\u51b5\u4e0b\u5c31\u76f4\u63a5\u7ed9\u4f60\u628a\u57fa\u5740\u5b9a\u4e3a0\u3002\u8fd9\u6837\u786e\u5b9e\u662f\u6bd4\u8f83\u65b9\u4fbf\u4e86\uff0c\u4efb\u4f55\u6570\u52a0\u4e0a0\u8fd8\u662f\u539f\u6765\u7684\u6570\uff0c\u4e8e\u662f\u903b\u8f91\u5730\u5740\u7b49\u4e8e\u7ebf\u6027\u5730\u5740\u3002\u90a3\u4e48\u628a\u903b\u8f91\u5730\u5740\u8f6c\u4e3a\u7269\u7406\u5730\u5740\u7684\u65f6\u5019\u5c31\u4e0d\u7406\u8fd9\u4e2a\u6b65\u9aa4\u4e86\uff0c\u76f4\u63a5\u53bb\u5904\u7406\u5206\u9875\u673a\u5236\u5c31\u597d\u4e86\u3002<br \/>\n\u5206\u9875\u7684\u8bdd\uff0cCPU\u7684\u67d0\u4e2a\u5bc4\u5b58\u5668\u4fdd\u5b58\u4e86\u201c\u9875\u8868\u201d\u7684\u5730\u5740\uff0c\u8fd9\u4e2a\u9875\u8868\u53ef\u80fd\u6709\u597d\u51e0\u7ea7\u3002\u7ebf\u6027\u5730\u5740\u7684\u6bcf\u4e2a\u90e8\u5206\u90fd\u4fdd\u5b58\u4e86\u6bcf\u4e00\u7ea7\u9700\u8981\u7684\u7d22\u5f15\uff08\u8bf4\u767d\u4e86\u5c31\u662f\u6570\u7ec4\u4e0b\u6807\uff09\uff0c\u7136\u540e\u6700\u540e\u4e00\u90e8\u5206\u4fdd\u5b58\u4e86\u504f\u79fb\u3002\u8fd9\u4e2a\u5728\u4e0b\u9762\u5177\u4f53\u60c5\u51b5\u7684\u65f6\u5019\u518d\u53bb\u7406\u89e3\u4f1a\u6bd4\u8f83\u5bb9\u6613\u3002<\/p>\n<p>\u5b9e\u9a8c\u5728NetBSD 6.1.4\u4e0a\u5b8c\u6210\u3002\u5df2\u7ecf\u901a\u8fc7<a href=\"https:\/\/blog.sorayuki.net\/?p=528\">\u8fd9\u4e00\u7bc7\u6587\u7ae0<\/a>\u4e2d\u4ecb\u7ecd\u7684\u65b9\u6cd5\u6dfb\u52a0\u4e86\u83b7\u53d6CR3\u5bc4\u5b58\u5668\u503c\u7684\u7cfb\u7edf\u8c03\u7528\uff0c\u8c03\u7528\u53f7\u662f475\u3002<\/p>\n<hr \/>\n<p><strong><span style=\"color: #0000ff;\">============================<strong><span style=\"color: #0000ff;\">============================<\/span><\/strong><br \/>\n1\u3001x86-32\uff0c\u672a\u5f00\u542fPAE\u7684\u60c5\u51b5<br \/>\n<strong><span style=\"color: #0000ff;\">============================<strong><span style=\"color: #0000ff;\">============================<\/span><\/strong><\/span><\/strong><\/span><\/strong><\/p>\n<p><a href=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image2.png\"><img loading=\"lazy\" decoding=\"async\" style=\"display: inline;\" title=\"image\" src=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image_thumb2.png\" alt=\"image\" width=\"582\" height=\"338\" \/><\/a><br \/>\n<a href=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image3.png\"><img loading=\"lazy\" decoding=\"async\" style=\"display: inline;\" title=\"image\" src=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image_thumb3.png\" alt=\"image\" width=\"584\" height=\"315\" \/><\/a><br \/>\n<a href=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image4.png\"><img loading=\"lazy\" decoding=\"async\" style=\"display: inline;\" title=\"image\" src=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image_thumb4.png\" alt=\"image\" width=\"582\" height=\"578\" \/><\/a><\/p>\n<p>\u8fd9\u4e24\u5f20\u56fe\u628a\u6574\u4e2a\u8fc7\u7a0b\u8bf4\u660e\u5f97\u975e\u5e38\u6e05\u695a\uff0c\u9996\u5148\u83b7\u53d6CR3\u5bc4\u5b58\u5668\u7684\u503c\uff0c\u7136\u540e\u901a\u8fc7\u8fd9\u4e2a\u503c\u627e\u5230Page Directory\uff0c\u518d\u6839\u636ePage Directory\u91cc\u7684\u6807\u5fd7\u4f4d\u786e\u5b9a\u8fd8\u8981\u4e0d\u8981\u7ee7\u7eed\u5230Page Table\u91cc\u9762\u53bb\u627e\uff1a\u56e0\u4e3aPage Directory\u91cc\u4e5f\u53ef\u80fd\u662f\u76f4\u63a5\u6307\u5411\u4e00\u4e2a4MB\u7684\u5185\u5b58\u9875\uff0c\u8fd9\u6839\u636ePage Directory Entry\u91cc\u7b2c7\uff08<strong>\u6700\u53f3\u4e3a\u7b2c0\u4f4d<\/strong>\uff09\u4f4d\uff08PS\u4f4d\uff0c\u5168\u79f0Page Size\uff09\u662f\u4e0d\u662f1\u6765\u51b3\u5b9a\u5b83\u6307\u5411\u7684\u662f\u4e00\u4e2aPage Table\u8fd8\u662f\u76f4\u63a5\u8868\u793a\u4e86\u4e00\u4e2a4MB\u7684\u5185\u5b58\u9875\u3002\u8fd9\u4e9b\u9875\u76ee\u5f55\u3001\u9875\u8868\u9879\u7684\u524d20\u4f4d\uff084MB\u5185\u5b58\u9875\u7684\u65f6\u5019\u662f\u524d10\u4f4d\uff09\u4ee3\u8868\u4e86\u57fa\u5730\u5740\uff0c\u5c31\u662f\u9875\u8868\u5177\u4f53\u5b58\u653e\u5728\u54ea\u91cc\u6216\u8005\u8fd9\u4e2a\u9875\u5177\u4f53\u5728\u54ea\u91cc\u3002\u7136\u540e\u6700\u540e\u4e00\u4f4d\uff08Present\u4f4d\uff09\u662f1\u8fd8\u662f0\u4ee3\u8868\u4e86\u8fd9\u4e2a\u9875\u9762\u662f\u5426\u5b58\u5728\u3002\u6709\u8fd9\u6837\u4e00\u79cd\u60c5\u51b5\uff0c\u5185\u5b58\u9875\u4f1a\u4e0d\u5b58\u5728\uff1a\u64cd\u4f5c\u7cfb\u7edf\u4e0d\u662f\u6709\u4e00\u4e2a\u673a\u5236\u53eb\u505a\u865a\u62df\u5185\u5b58\u5417\uff1f\u53ef\u4ee5\u901a\u8fc7\u5c06\u6682\u65f6\u4e0d\u7528\u7684\u5185\u5b58\u9875\u5199\u5165\u786c\u76d8\uff0c\u817e\u51fa\u8fd9\u90e8\u5206\u7a7a\u95f4\u7ed9\u6025\u9700\u5185\u5b58\u7684\u7a0b\u5e8f\u4f7f\u7528\uff0c\u8fd9\u4e9b\u6570\u636e\u5982\u679c\u4ee5\u540e\u53c8\u8981\u7528\u4e86\uff0c\u5c31\u518d\u4ece\u786c\u76d8\u4e2d\u8bfb\u51fa\u6765\u3002\u90a3\u4e48\u5982\u679c\u4e00\u4e2a\u9875\u9762\u6b63\u597d\u88ab\u653e\u5165\u786c\u76d8\u4e86\uff0c\u5c31\u6709\u53ef\u80fd\u660e\u660e\u662f\u4e00\u4e2a\u53ef\u4ee5\u8bbf\u95ee\u7684\u5730\u5740\uff0c\u4f46\u662f\u8fd9\u4e2a\u6700\u540e\u4e00\u4f4d\u5374\u662f0\u3002\u5173\u4e8e\u8fd9\u4e9b\u4f4d\u7684\u8be6\u7ec6\u89e3\u91ca\uff0c\u770bIntel\u7684\u6587\u6863\u5c31\u80fd\u5f88\u6e05\u695a\u4e86\u3002<\/p>\n<p>\u8fd9\u91cc\u9762\uff0cCR3\u548cPage Directory Entry\u548cPage Table Entry\u6d89\u53ca\u5230\u7684\u201c\u5730\u5740\u201d\u5168\u90e8\u90fd\u6307\u7684\u662f\u7269\u7406\u5730\u5740\u3002<\/p>\n<p>\u7136\u540e\u901a\u8fc7 \/dev\/mem \u6765\u64cd\u4f5c\u7269\u7406\u5185\u5b58\uff0c\u5c31\u53ef\u4ee5\u5199\u4e00\u4e2a\u7a0b\u5e8f\u5c06\u865a\u62df\u5730\u5740\u8f6c\u4e3a\u7269\u7406\u5730\u5740\uff0c\u7136\u540e\u9a8c\u8bc1\u662f\u5426\u6b63\u786e\u3002\u4e00\u4e2a\u7b80\u5355\u7684\u65b9\u6cd5\uff0c\u5c31\u662f\u58f0\u660e\u4e00\u4e2a\u53d8\u91cf\uff0c\u7136\u540e\u628a\u5b83\u7684\u5730\u5740\u8f6c\u6210\u7269\u7406\u5730\u5740\uff0c\u901a\u8fc7\u5199\u5165 \/dev\/mem \u6765\u6539\u53d8\u5b83\u7684\u503c\uff0c\u6700\u540e\u8bfb\u53d6\u8fd9\u4e2a\u53d8\u91cf\u770b\u770b\u5b83\u7684\u503c\u6709\u6ca1\u6709\u53d8\u3002\u8fd9\u4e2a\u8fc7\u7a0b\u4e2d\u6709\u4e00\u4e2a\u9700\u8981\u6ce8\u610f\u7684\u5730\u65b9\uff0c\u5c31\u662f\u5982\u679c\u4e00\u4e2a\u9875\u76ee\u5f55\u9879\u6216\u8005\u9875\u8868\u9879\u7684\u672b\u4f4d\u4e3a0\uff0c\u5c31\u76f4\u63a5\u8ba4\u4e3a\u8f6c\u6362\u5931\u8d25\u4e86\u3002\u4ee5\u53ca<span style=\"color: #ff0000;\"><strong>\u5c31\u7b97\u8f6c\u51fa\u4e86\u7269\u7406\u5730\u5740\uff0c\u5982\u679c\u5728\u8f6c\u5b8c\u4e4b\u540e\u8bbf\u95ee\u4e4b\u524d\u6b63\u597d\u9047\u4e0a\u64cd\u4f5c\u7cfb\u7edf\u628a\u8fd9\u4e2a\u5185\u5b58\u9875\u6362\u5230\u786c\u76d8\u7684\u4ea4\u6362\u5206\u533a\u53bb\u4e86\uff0c\u4e5f\u662f\u4f1a\u51fa\u9519\u7684\u3002<\/strong><\/span>\u6240\u4ee5\u8fd9\u4e2a\u4ec5\u4ec5\u662f\u5b9e\u9a8c\uff0c\u771f\u6b63\u5b9e\u7528\u8981\u8003\u8651\u7684\u4e1c\u897f\u5b9e\u5728\u662f\u975e\u5e38\u591a\uff0c\u4e0d\u8981\u8d38\u7136\u641e\u8fd9\u6837\u7684\u65b9\u6cd5\u3002\u8981\u8ba9\u5185\u6838\u628a\u8fd9\u4e2a\u5206\u9875\u6362\u56de\u6765\u867d\u7136\u4e5f\u4e0d\u96be\uff0c\u6bd4\u5982\u8bbf\u95ee\u4e00\u4e0b\u8fd9\u4e2a\u53d8\u91cf\u4e4b\u7c7b\u2026\u2026\u4e0d\u8fc7\u8fd9\u6837\u7a0b\u5e8f\u903b\u8f91\u5c31\u53d8\u9ebb\u70e6\u4e86\uff0c\u800c\u4e14\u53c8\u53cd\u6b63\u662f\u5b9e\u9a8c\u561b\uff0c\u5c31\u968f\u4fbf\u6765\u4e86\uff08\u6bb4\uff09\u3002\u5b9e\u9645\u5b9e\u9a8c\u8fc7\u7a0b\u4e2d\uff0c\u56e0\u4e3a\u7a0b\u5e8f\u4f53\u79ef\u5c0f\u5360\u7684\u5185\u5b58\u5c11\uff0c\u53c8\u56e0\u4e3a\u662f\u865a\u62df\u673a\u91cc\u9762\u3001\u7cfb\u7edf\u6839\u672c\u6ca1\u8fd0\u884c\u5176\u4ed6\u4e1c\u897f\uff0c\u6240\u4ee5\u6ca1\u9047\u5230\u8fd9\u79cd\u60c5\u51b5\u3002<\/p>\n<p>\u4e8e\u662f\u6709\u5982\u4e0b\u6d4b\u8bd5\u7a0b\u5e8f\uff1a<\/p>\n<pre>#include &lt;unistd.h&gt;\r\n#include &lt;cstdio&gt;\r\n#include &lt;fcntl.h&gt;\r\n#include &lt;stdint.h&gt;\r\nusing namespace std;\r\n\r\nstruct PhyAddr {\r\n    uint32_t m_phyaddr;\r\n    PhyAddr(uint32_t addr = 0) : m_phyaddr(addr)\r\n    {\r\n    }\r\n    PhyAddr&amp; operator += (uint32_t offset)\r\n    {\r\n        m_phyaddr += offset;\r\n        return *this;\r\n    }\r\n};\r\n\r\nbool AccessPhyMem(PhyAddr addr, bool isRead, void* buf, int len)\r\n{\r\n    int fd = open(\"\/dev\/mem\", O_RDWR);\r\n    if (fd &lt;= 0)\r\n        return false;\r\n    lseek(fd, addr.m_phyaddr, SEEK_SET);\r\n    if (isRead)\r\n        read(fd, buf, len);\r\n    else\r\n        write(fd, buf, len);\r\n    close(fd);\r\n    return true;\r\n}\r\n\r\nstruct PageItemEntry {\r\n    uint32_t m_entry;\r\n    operator PhyAddr ()\r\n    {\r\n        PhyAddr r;\r\n        r.m_phyaddr = m_entry &amp; 0xfffff000;\r\n        return r;\r\n    }\r\n    bool IsPresent()\r\n    {\r\n        return (m_entry &amp; 1) == 1;\r\n    }\r\n};\r\n\r\nstruct PageDirEntry : public PageItemEntry {\r\n    bool Is4MPage()\r\n    {\r\n        return (m_entry &amp; 0x80) != 0;\r\n    }\r\n    operator PhyAddr ()\r\n    {\r\n        PhyAddr r = PageItemEntry::operator PhyAddr();\r\n        if (Is4MPage())\r\n            r.m_phyaddr &amp;= 0xffc00000;\r\n        return r;\r\n    }\r\n};\r\n\r\nstruct PageTblEntry : public PageItemEntry {\r\n};\r\n\r\nvoid SplitPtr(void* ptr, int* nDirIndex, int* nTblIndex, int* nOffset, int* nOffset2)\r\n{\r\n    *nDirIndex = (uint32_t)ptr &gt;&gt; 22;\r\n    *nTblIndex = ((uint32_t)ptr &gt;&gt; 12) &amp; 0x3ff;\r\n    *nOffset = (uint32_t)ptr &amp; 0xfff;\r\n    *nOffset2 = (uint32_t)ptr &amp; 0x003fffff;\r\n}\r\n\r\nint main()\r\n{\r\n    volatile int var = 0xfbfbfbfb;\r\n    int val = 0x12349876;\r\n    int nDirIndex, nTblIndex, nOffset, nOffset2;\r\n    SplitPtr((void*)&amp;var, &amp;nDirIndex, &amp;nTblIndex, &amp;nOffset, &amp;nOffset2);\r\n    \r\n    try {\r\n        PhyAddr cr3 = syscall(475);\r\n        PhyAddr varAddr;\r\n        PageDirEntry pageDir[1024];\r\n        AccessPhyMem(cr3, true, pageDir, sizeof(pageDir));\r\n        if (!pageDir[nDirIndex].IsPresent())\r\n            throw \"Fail: Invalid page directory entry.\";\r\n\r\n        if (pageDir[nDirIndex].Is4MPage()) {\r\n            varAddr = pageDir[nDirIndex];\r\n            varAddr += nOffset2;\r\n            AccessPhyMem(varAddr, false, &amp;val, sizeof(val)); \r\n        } else {\r\n            PageTblEntry pageTbl[1024];\r\n            AccessPhyMem(pageDir[nDirIndex], true, pageTbl, sizeof(pageTbl));\r\n            if (!pageTbl[nTblIndex].IsPresent())\r\n                throw \"Fail: Invalid page table entry.\";\r\n            varAddr = pageTbl[nTblIndex];\r\n            varAddr += nOffset;\r\n            AccessPhyMem(varAddr, false, &amp;val, sizeof(val));\r\n        }\r\n\r\n        printf(\"%x\\n\", var);\r\n    } catch(const char* msg) {\r\n        fprintf(stderr, \"%s\\n\", msg);\r\n    }\r\n    return 0;\r\n}\r\n\r\n<\/pre>\n<p>\u7b80\u5355\u8bf4\u5c31\u662f\u901a\u8fc7\u628avar\u7684\u5730\u5740\u8f6c\u6210\u7269\u7406\u5730\u5740\uff0c\u7136\u540e\u628aval\u7684\u503c\u5199\u5165\u8fd9\u4e2a\u5730\u5740\uff0c\u6700\u540e\u8f93\u51favar\u770b\u770b\u662f\u5426\u88ab\u6539\u53d8\u4e86\u3002<\/p>\n<p><span style=\"color: #ff0000;\">\u8fd8\u662f\u4e0a\u9762\u8bf4\u7684\uff1a\u5c31\u7b97\u90fd\u68c0\u67e5\u4e86 IsPresent() \uff0c\u53ea\u8981\u8f6c\u6210\u7269\u7406\u5730\u5740\u4e4b\u540e\u6b63\u597d\u53d1\u751f\u9875\u9762\u4ea4\u6362\u628avar\u6240\u5728\u9875\u9762\u8c03\u5165swap\uff0c\u8fd9\u4e2a\u5199\u5165\u4ecd\u7136\u662f\u6709\u95ee\u9898\u7684\u3002\u53ea\u662f\u56e0\u4e3a\u73b0\u5728\u662f\u5b9e\u9a8c\u6240\u4ee5\u624d\u8fd9\u4e48\u505a\u3002<\/span><\/p>\n<p>\u987a\u4fbf\uff0c\u5982\u679c\u63d0\u4f9b\u7684\u662f\u53e6\u4e00\u4e2a\u8fdb\u7a0b\u7684CR3\u548c\u53e6\u4e00\u4e2a\u8fdb\u7a0b\u91cc\u7684\u67d0\u4e2a\u53d8\u91cf\u7684\u5730\u5740\uff0c\u90a3\u4e48\u53ef\u4ee5\u76f4\u63a5\u4fee\u6539\u53e6\u4e00\u4e2a\u8fdb\u7a0b\u91cc\u9762\u7684\u53d8\u91cf\u3002\u6ce8\u610fvolatile\u5173\u952e\u8bcd\uff0c\u514d\u5f97\u7f16\u8bd1\u5668\u751f\u6210\u7684\u4ee3\u7801\u5728\u4f60\u8981\u8f93\u51fa\u7684\u5730\u65b9\u4e0d\u91cd\u8bfb\u53d8\u91cf\u3002<\/p>\n<hr \/>\n<p><strong><span style=\"color: #0000ff;\">============================<strong><span style=\"color: #0000ff;\">============================<\/span><\/strong><\/span><\/strong><strong><span style=\"color: #0000ff;\"><br \/>\n2\u3001x86-32\uff0c\u5f00\u542fPAE\u7684\u60c5\u51b5<br \/>\n<strong><span style=\"color: #0000ff;\">============================<strong><span style=\"color: #0000ff;\">============================<\/span><\/strong><\/span><\/strong><\/span><\/strong><\/p>\n<p>\u5230 \/usr\/src\/sys\/arch\/i386\/conf \u91cc\u9762\u627e\u5230 GENERIC \u6587\u4ef6\uff0c\u628a\u91cc\u9762\u7684 #options PAE \u6700\u524d\u9762\u7684 # \u53bb\u6389\uff0c\u7136\u540econfig GENERIC\u4e4b\u540e\u7f16\u8bd1\u5b89\u88c5\u65b0\u5185\u6838\u3002\u8fd9\u4e2a\u5185\u6838\u5c31\u662f\u542f\u7528PAE\u7684\u5185\u6838\u4e86\u3002\u63a5\u4e0b\u53bb\u7684\u5b9e\u9a8c\u5c31\u5728\u8fd9\u4e2a\u5185\u6838\u4e0a\u8fdb\u884c\u3002<\/p>\n<p><a href=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image5.png\"><img loading=\"lazy\" decoding=\"async\" style=\"display: inline;\" title=\"image\" src=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image_thumb5.png\" alt=\"image\" width=\"585\" height=\"393\" \/><\/a><br \/>\n<a href=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image6.png\"><img loading=\"lazy\" decoding=\"async\" style=\"display: inline;\" title=\"image\" src=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image_thumb6.png\" alt=\"image\" width=\"588\" height=\"342\" \/><\/a><br \/>\n<a href=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image7.png\"><img loading=\"lazy\" decoding=\"async\" style=\"display: inline;\" title=\"image\" src=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image_thumb7.png\" alt=\"image\" width=\"585\" height=\"472\" \/><\/a><\/p>\n<p>\u8fd9\u4e2a\u56fe\u4e0a\u6682\u65f6\u80fd\u770b\u51fa\u7684\u662f\uff0c\u4e00\u4e2a\u6307\u9488\u672c\u6765\u662f\u5206\u62103\u90e8\u5206\u6216\u80052\u90e8\u5206\uff0c\u73b0\u5728\u53d8\u62104\u90e8\u5206\u6216\u80053\u90e8\u5206\u4e86\uff1a\u591a\u4e86\u4e00\u7ea7\u3002\u4ee5\u53ca\uff0c\u9875\u76ee\u5f55\u3001\u9875\u8868\u7684\u7d22\u5f15\u672c\u6765\u662f10\u4f4d\uff0c\u73b0\u5728\u53d8\u6210\u4e869\u4f4d\uff08\u591a\u7684\u4e00\u7ea7\u662f2\u4f4d\uff09\uff0c\u6700\u540e12\u4f4d\u57284K\u5185\u5b58\u9875\u7684\u65f6\u5019\u662f\u4e0d\u53d8\u7684\uff0c\u4f46\u662f\u57282MB\u5185\u5b58\u9875\u7684\u65f6\u5019\u53d8\u621020\u4f4d\u4e86\uff08\u56e0\u4e3a\u53d8\u62102MB\u4e86\u561b\u2026\u2026\u672c\u6765\u662f4MB\uff09\u3002<\/p>\n<p>\u4f46\u662f\u4e00\u4e2a\u66f4\u5927\u7684\u533a\u522b\u662f\uff0cPAE\u6a21\u5f0f\u4e0b\uff0c\u9875\u8868\u9879\u3001\u9875\u76ee\u5f55\u9879\u4e4b\u7c7b\u7684\u9879\u90fd\u662f64\u4f4d\u7684\u4e86\u3002\u5176\u5b9e\u4e5f\u5c31\u662f\u539f\u676532\u4f4d\u524d\u9762\u591a\u4e8632\u4f4d\u9ad8\u5730\u5740\uff0c\u518d\u628a\u539f\u67651024\u4e2a\u9879\u53d8\u6210512\u4e2a\u9879\uff0c\u5176\u4ed6\u5176\u5b9e\u8fd8\u662f\u4e00\u6837\u3002\u7136\u540e\u4ed4\u7ec6\u770b\uff0c<span style=\"color: #ff0000;\"><strong>\u591a\u4e86\u597d\u591aReserved\u7684\u90e8\u5206<\/strong><\/span>\uff0c\u539f\u676532\u4f4d\u7684\u65f6\u5019\u6ca1\u6709\u8fd9\u4e9b\u4e1c\u897f\u7684\u3002\u56e0\u4e3aPAE\u5b9e\u9645\u4e0a\u5c31\u652f\u6301\u523036\u4f4d\u5730\u5740\uff08\u6ce8\uff1aIntel\u7684\u8bf4\u660e\u6587\u6863\u4e2d\u6709\u8fd9\u4e48\u4e00\u53e5 NOTES: 1. MAXPHYADDR is 36-bits on processors that do not support CPUID.80000008H leaf. On processors that do support CPUID.80000008H, MAXPHYADDR is implementation-specific and indicated by CPUID.80000008H:EAX[bits 7:0]. \u4f46\u662f\u6211\u6ca1\u770b\u61c2\u600e\u4e48\u6837\u80fd\u8ba9\u5b83\u7a81\u783436\u4f4d\u3002NetBSD\u4e0b\u628a\u90a3\u4e2aReversed\u7684\u6700\u9ad8\u4f4d\u62ff\u6765\u7528\u4e86\uff09\uff0c\u6240\u4ee5<span style=\"color: #ff0000;\"><strong>36\u4f4d\u5f80\u4e0a\u7684\u90e8\u5206\u8981mask\u6389<\/strong><\/span>\uff08P.S. \u6211\u6700\u521d\u505a\u5b9e\u9a8c\u7684\u65f6\u5019\u6ca1\u6709mask\u6389\uff0c\u7ed3\u679c\u51fa\u6765\u7684\u7ed3\u679c\u5f88\u5947\u602a\uff0c\u540e\u6765\u628a\u5b83\u4eecdump\u51fa\u6765\u4e00\u770b\u624d\u53d1\u73b0reserved\u90a3\u8fb9\u4e0d\u662f0\uff09\u3002\u6240\u4ee5\u6709\u4e86\u4e0b\u9762\u7684\u5b9e\u9a8c\u4ee3\u7801\uff1a<\/p>\n<pre>#include &lt;unistd.h&gt;\r\n#include &lt;cstdio&gt;\r\n#include &lt;fcntl.h&gt;\r\n#include &lt;stdint.h&gt;\r\nusing namespace std;\r\n\r\nstruct PhyAddr {\r\n    uint64_t m_phyaddr;\r\n    PhyAddr(uint64_t addr = 0) : m_phyaddr(addr)\r\n    {\r\n    }\r\n    PhyAddr&amp; operator += (uint64_t offset)\r\n    {\r\n        m_phyaddr += offset;\r\n        return *this;\r\n    }\r\n};\r\n\r\nbool AccessPhyMem(PhyAddr addr, bool isRead, void* buf, int len)\r\n{\r\n    int fd = open(\"\/dev\/mem\", O_RDWR);\r\n    if (fd &lt;= 0)\r\n        return false;\r\n    lseek(fd, addr.m_phyaddr, SEEK_SET);\r\n    if (isRead)\r\n        read(fd, buf, len);\r\n    else\r\n        write(fd, buf, len);\r\n    close(fd);\r\n    return true;\r\n}\r\n\r\nstruct PageItemEntry {\r\n    uint64_t m_entry;\r\n    operator PhyAddr ()\r\n    {\r\n        PhyAddr r;\r\n        r.m_phyaddr = m_entry &amp; 0xffffff000ull;\r\n        return r;\r\n    }\r\n    bool IsPresent()\r\n    {\r\n        return (m_entry &amp; 1) == 1;\r\n    }\r\n};\r\n\r\nstruct PageDirPtrEntry : public PageItemEntry {\r\n};\r\n\r\n\r\nstruct PageDirEntry : public PageItemEntry {\r\n    bool Is2MPage()\r\n    {\r\n        return (m_entry &amp; 0x80) != 0;\r\n    }\r\n    operator PhyAddr ()\r\n    {\r\n        PhyAddr r = PageItemEntry::operator PhyAddr();\r\n        if (Is2MPage())\r\n            r.m_phyaddr &amp;= 0xffff00000ull;\r\n        return r;\r\n    }\r\n};\r\n\r\nstruct PageTblEntry : public PageItemEntry {\r\n};\r\n\r\nvoid SplitPtr(void* ptr, int* nDirPtrIndex, int* nDirIndex, int* nTblIndex, int* nOffset, int* nOffset2)\r\n{\r\n    *nDirPtrIndex = (uint32_t)ptr &gt;&gt; 30;\r\n    *nDirIndex = ((uint32_t)ptr &gt;&gt; 21) &amp; 0x1ff;\r\n    *nTblIndex = ((uint32_t)ptr &gt;&gt; 12) &amp; 0x1ff;\r\n    *nOffset = (uint32_t)ptr &amp; 0xfff;\r\n    *nOffset2 = (uint32_t)ptr &amp; 0x000fffff;\r\n}\r\n\r\nint main()\r\n{\r\n    volatile int var = 0xfbfbfbfb;\r\n    int val = 0x12349876;\r\n    int nDirPtrIndex, nDirIndex, nTblIndex, nOffset, nOffset2;\r\n    SplitPtr((void*)&amp;var, &amp;nDirPtrIndex, &amp;nDirIndex, &amp;nTblIndex, &amp;nOffset, &amp;nOffset2);\r\n    try {\r\n        PhyAddr cr3 = syscall(475);\r\n        PhyAddr varAddr;\r\n        PageDirPtrEntry pageDirPtr[4];\r\n        AccessPhyMem(cr3, true, pageDirPtr, sizeof(pageDirPtr));\r\n        if (!pageDirPtr[nDirPtrIndex].IsPresent())\r\n            throw \"Fail: Invalid page directory pointer entry.\";\r\n        \r\n        PageDirEntry pageDir[512];\r\n        AccessPhyMem(pageDirPtr[nDirPtrIndex], true, pageDir, sizeof(pageDir));\r\n        if (!pageDir[nDirIndex].IsPresent())\r\n            throw \"Fail: Invalid page directory entry.\";\r\n\r\n        if (pageDir[nDirIndex].Is2MPage()) {\r\n            varAddr = pageDir[nDirIndex];\r\n            varAddr += nOffset2;\r\n            AccessPhyMem(varAddr, false, &amp;val, sizeof(val)); \r\n        } else {\r\n            PageTblEntry pageTbl[512];\r\n            AccessPhyMem(pageDir[nDirIndex], true, pageTbl, sizeof(pageTbl));\r\n            if (!pageTbl[nTblIndex].IsPresent())\r\n                throw \"Fail: Invalid page table entry.\";\r\n            varAddr = pageTbl[nTblIndex];\r\n            varAddr += nOffset;\r\n            AccessPhyMem(varAddr, false, &amp;val, sizeof(val));\r\n        }\r\n\r\n        printf(\"%x\\n\", var);\r\n    } catch(const char* msg) {\r\n        fprintf(stderr, \"%s\\n\", msg);\r\n    }\r\n    return 0;\r\n}\r\n\r\n<\/pre>\n<p>\u6548\u679c\u548c\u4e0a\u9762\u90a3\u4e2a\u7a0b\u5e8f\u662f\u4e00\u6837\u7684\uff0c\u5c31\u662f\u5728PAE\u4e0b\u7684\u8f6c\u6362\u3002<\/p>\n<hr \/>\n<p><strong><span style=\"color: #0000ff;\">============================<strong><span style=\"color: #0000ff;\">============================<br \/>\n3\u3001x86-64\uff08AMD64\uff0cIA-32e\uff09\u7684\u60c5\u51b5<br \/>\n<strong><span style=\"color: #0000ff;\">============================<strong><span style=\"color: #0000ff;\">============================<\/span><\/strong><\/span><\/strong><\/span><\/strong><\/span><\/strong><\/p>\n<p>&nbsp;<\/p>\n<p>\u5728x86-64\uff08\u4ee5\u4e0b\u7b80\u79f064\u4f4d\uff09\u4e0b\uff0cPAE\u5f3a\u5236\u5f00\u542f\uff0c\u903b\u8f91\u5730\u5740\u7684\u957f\u5ea6\u6269\u5145\u4e3a48\u4f4d\uff0c\u7269\u7406\u5730\u5740\u5219\u53ef\u4ee5\u4f7f\u752852\u4f4d\uff08\u76f8\u6bd4\u8d77\u6765\uff0c32\u4f4d\u4e0b32\u4f4d\u7269\u7406\u5730\u5740\u6700\u5927\u8303\u56f4\u662f4G\uff0c32\u4f4dPAE\u4e0b36\u4f4d\u7269\u7406\u5730\u5740\u6700\u5927\u8303\u56f4\u662f64G\uff0c\u800c52\u4f4d\u5730\u5740\u5219\u610f\u5473\u7740\u8303\u56f4\u5230\u4e864194304GB\uff0c\u4e5f\u5c31\u662f4096TB\uff09\u3002\u6240\u4ee5\u5927\u5185\u5b58\u7684\u65f6\u5019\u8fd8\u662f\u8981\u976064\u4f4d\u3002<\/p>\n<p>\u572864\u4f4dPAE\u4e0b\uff0c\u9875\u8868\u6bd432\u4f4dPAE\u591a\u4e86\u4e00\u7ea7\uff0c\u53d8\u6210\u56db\u7ea7\u9875\u8868\u3002\u65b0\u589e\u52a0\u7684\u4e00\u7ea7\u547d\u540d\u4e3aPML4\uff08page map level 4\uff0c\u7ee7Page Table\uff0cPage Directory\uff0cPage Directory Pointer\u4e4b\u540e\u7ec8\u4e8e\u76f4\u63a5\u7b80\u5355\u7c97\u66b4\u7528\u8d77\u6570\u5b57\u6765\u4e86\uff09\u3002\u4f46\u662f\u6362\u6c64\u4e0d\u6362\u836f\uff0c\u5c31\u662f\u67e5\u627e\u7684\u65f6\u5019\u591a\u4e86\u4e00\u7ea7\u800c\u5df2\u3002\u7ed3\u6784\u548c\u539f\u6765\u57fa\u672c\u4e00\u81f4\uff0c32\u4f4d\u7684\u90a3\u51e0\u4e2a\u5982\u679c\u6ca1\u5199\u9519\uff0c\u7167\u7740\u6539\u6539\u572864\u4f4d\u4e0b\u5c31\u80fd\u8dd1\u4e86\u3002<\/p>\n<p><a href=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image8.png\"><img loading=\"lazy\" decoding=\"async\" style=\"margin: 0px; display: inline;\" title=\"image\" src=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image_thumb8.png\" alt=\"image\" width=\"580\" height=\"496\" \/><\/a><br \/>\n<a href=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image9.png\"><img loading=\"lazy\" decoding=\"async\" style=\"display: inline;\" title=\"image\" src=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image_thumb9.png\" alt=\"image\" width=\"581\" height=\"495\" \/><\/a><br \/>\n<a href=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image10.png\"><img loading=\"lazy\" decoding=\"async\" style=\"display: inline;\" title=\"image\" src=\"https:\/\/blog.sorayuki.net\/wp-content\/uploads\/2014\/09\/image_thumb11.png\" alt=\"image\" width=\"581\" height=\"587\" \/><\/a><\/p>\n<p>\u56e0\u4e3a\u6362\u4e8664\u4f4d\u7cfb\u7edf\uff0c\u4e4b\u524d\u6dfb\u52a0\u8fc7\u7684\u7cfb\u7edf\u8c03\u7528\u8fd8\u8981\u91cd\u65b0\u6dfb\u52a0\u4e00\u6b21\uff08\u597d\u5427\u6211\u6362\u4e86\u4e00\u53f0\u865a\u62df\u673a\u88c5\u4e86\u4e2aAMD64\u7684\uff09\u3002\u89e3\u5305\u51fa\u6e90\u4ee3\u7801\uff0c\u7136\u540e\u5230 \/usr\/src\/sys\/kern\/syscalls.master \u91cc\u9762\u53bb\u52a0\u7cfb\u7edf\u8c03\u7528\u7136\u540emake init_sysent.c\u4e00\u4e0b\uff0c\u518d\u5230 \/usr\/src\/sys\/arch\/amd64\/conf\/files.amd64 \u6dfb\u52a0\u4e00\u4e2a\u6e90\u4ee3\u7801\u6587\u4ef6\uff0c\u5e76\u5728\u6e90\u4ee3\u7801\u6587\u4ef6\u4e2d\u5199\u597d\u5b9e\u73b0\u3002cr3\u8fd8\u662f\u5728\u539f\u6765\u7684\u5730\u65b9\uff1a\u4ecelwp\u7ed3\u6784\u4f53\u83b7\u53d6\u5230pcb\uff0c\u7136\u540epcb_cr3\u6210\u5458\u5c31\u662f\u3002<\/p>\n<pre>#include &lt;unistd.h&gt;\r\n#include &lt;cstdio&gt;\r\n#include &lt;fcntl.h&gt;\r\n#include &lt;stdint.h&gt;\r\nusing namespace std;\r\n\r\nstruct PhyAddr {\r\n    uint64_t m_phyaddr;\r\n    PhyAddr(uint64_t addr = 0) : m_phyaddr(addr)\r\n    {\r\n    }\r\n    PhyAddr&amp; operator += (uint64_t offset)\r\n    {\r\n        m_phyaddr += offset;\r\n        return *this;\r\n    }\r\n};\r\n\r\nbool AccessPhyMem(PhyAddr addr, bool isRead, void* buf, int len)\r\n{\r\n    int fd = open(\"\/dev\/mem\", O_RDWR);\r\n    if (fd &lt;= 0)\r\n        return false;\r\n    lseek(fd, addr.m_phyaddr, SEEK_SET);\r\n    if (isRead)\r\n        read(fd, buf, len);\r\n    else\r\n        write(fd, buf, len);\r\n    close(fd);\r\n    return true;\r\n}\r\n\r\nstruct PageItemEntry {\r\n    uint64_t m_entry;\r\n    operator PhyAddr ()\r\n    {\r\n        PhyAddr r;\r\n        r.m_phyaddr = m_entry &amp; 0xfffffffff000ull;\r\n        return r;\r\n    }\r\n    bool IsPresent()\r\n    {\r\n        return (m_entry &amp; 1) == 1;\r\n    }\r\n};\r\n\r\nstruct PML4Entry : public PageItemEntry {\r\n};\r\n\r\nstruct PageDirPtrEntry : public PageItemEntry {\r\n};\r\n\r\n\r\nstruct PageDirEntry : public PageItemEntry {\r\n    bool Is2MPage()\r\n    {\r\n        return (m_entry &amp; 0x80) != 0;\r\n    }\r\n    operator PhyAddr ()\r\n    {\r\n        PhyAddr r = PageItemEntry::operator PhyAddr();\r\n        if (Is2MPage())\r\n            r.m_phyaddr &amp;= 0xfffffff00000ull;\r\n        return r;\r\n    }\r\n};\r\n\r\nstruct PageTblEntry : public PageItemEntry {\r\n};\r\n\r\nvoid SplitPtr(void* ptr, int* nPML4Index, int* nDirPtrIndex, int* nDirIndex, int* nTblIndex, int* nOffset, int* nOffset2)\r\n{\r\n    *nPML4Index = ((uint64_t)ptr &gt;&gt; 39) &amp; 0x1ff;\r\n    *nDirPtrIndex = ((uint64_t)ptr &gt;&gt; 30) &amp; 0x1ff;\r\n    *nDirIndex = ((uint64_t)ptr &gt;&gt; 21) &amp; 0x1ff;\r\n    *nTblIndex = ((uint64_t)ptr &gt;&gt; 12) &amp; 0x1ff;\r\n    *nOffset = (uint64_t)ptr &amp; 0xfff;\r\n    *nOffset2 = (uint64_t)ptr &amp; 0x000fffff;\r\n}\r\n\r\nint main()\r\n{\r\n    volatile int var = 0xfbfbfbfb;\r\n    int val = 0x12349876;\r\n    int nPML4Index, nDirPtrIndex, nDirIndex, nTblIndex, nOffset, nOffset2;\r\n    SplitPtr((void*)&amp;var, &amp;nPML4Index, &amp;nDirPtrIndex, &amp;nDirIndex, &amp;nTblIndex, &amp;nOffset, &amp;nOffset2);\r\n    try {\r\n        PhyAddr cr3 = syscall(475);\r\n        PhyAddr varAddr;\r\n        \r\n        PML4Entry pageMapL4[512];\r\n        AccessPhyMem(cr3, true, pageMapL4, sizeof(pageMapL4));\r\n        if (!pageMapL4[nPML4Index].IsPresent())\r\n            throw \"Fail: Invalid PML4 entry.\";\r\n        \r\n        PageDirPtrEntry pageDirPtr[512];\r\n        AccessPhyMem(pageMapL4[nPML4Index], true, pageDirPtr, sizeof(pageDirPtr));\r\n        if (!pageDirPtr[nDirPtrIndex].IsPresent())\r\n            throw \"Fail: Invalid page directory pointer entry.\";\r\n        \r\n        PageDirEntry pageDir[512];\r\n        AccessPhyMem(pageDirPtr[nDirPtrIndex], true, pageDir, sizeof(pageDir));\r\n        if (!pageDir[nDirIndex].IsPresent())\r\n            throw \"Fail: Invalid page directory entry.\";\r\n\r\n        if (pageDir[nDirIndex].Is2MPage()) {\r\n            varAddr = pageDir[nDirIndex];\r\n            varAddr += nOffset2;\r\n            AccessPhyMem(varAddr, false, &amp;val, sizeof(val)); \r\n        } else {\r\n            PageTblEntry pageTbl[512];\r\n            AccessPhyMem(pageDir[nDirIndex], true, pageTbl, sizeof(pageTbl));\r\n            if (!pageTbl[nTblIndex].IsPresent())\r\n                throw \"Fail: Invalid page table entry.\";\r\n            varAddr = pageTbl[nTblIndex];\r\n            varAddr += nOffset;\r\n            AccessPhyMem(varAddr, false, &amp;val, sizeof(val));\r\n        }\r\n\r\n        printf(\"%x\\n\", var);\r\n    } catch(const char* msg) {\r\n        fprintf(stderr, \"%s\\n\", msg);\r\n    }\r\n    return 0;\r\n}\r\n\r\n<\/pre>\n<p>\u548c32\u4f4dPAE\u7684\u60c5\u51b5\u57fa\u672c\u4e00\u6837\uff0c\u591a\u4e86\u4e00\u7ea7\uff0cPage Directory Pointer\u53d8\u6210\u4e86512\u4e2a\u5143\u7d20\uff0c\u4ee5\u53ca\u903b\u8f91\u5730\u5740\u53d8\u6210\u4e8648\u4f4d\u3002<\/p>\n<p><strong><span style=\"color: #0000ff;\">==============================================<br \/>\n4\u3001\u603b\u7ed3\u4e00\u4e0b<br \/>\n==============================================<\/span><\/strong><\/p>\n<table style=\"font-size: 12px;\">\n<tbody>\n<tr>\n<td>\u6a21\u5f0f<\/td>\n<td>\u903b\u8f91 \/ \u7269\u7406<br \/>\n\u5730\u5740\u957f\u5ea6<\/td>\n<td>\u9875\u8868\u7ea7\u6570<\/td>\n<td>\u6bcf\u7ea7\u9879\u6570<\/td>\n<td>\u6bcf\u9879\u957f\u5ea6<\/td>\n<td>\u9875\u5927\u5c0f<\/td>\n<\/tr>\n<tr>\n<td rowspan=\"2\">x86-32<\/td>\n<td rowspan=\"2\">32\/32\u4f4d<\/td>\n<td>2\u7ea7<\/td>\n<td>1024\/1024<\/td>\n<td rowspan=\"2\">32\u4f4d<\/td>\n<td>4KB<\/td>\n<\/tr>\n<tr>\n<td>1\u7ea7<\/td>\n<td>1024<\/td>\n<td>4MB<\/td>\n<\/tr>\n<tr>\n<td rowspan=\"2\">x86-32 PAE<\/td>\n<td rowspan=\"2\">32\/36\u4f4d<\/td>\n<td>3\u7ea7<\/td>\n<td>4\/512\/512<\/td>\n<td rowspan=\"2\">64\u4f4d<\/td>\n<td>4KB<\/td>\n<\/tr>\n<tr>\n<td>2\u7ea7<\/td>\n<td>4\/512<\/td>\n<td>2MB<\/td>\n<\/tr>\n<tr>\n<td rowspan=\"2\">x86-64<\/td>\n<td rowspan=\"2\">48\/52\u4f4d<\/td>\n<td>4\u7ea7<\/td>\n<td>512\/512\/512\/512<\/td>\n<td rowspan=\"2\">64\u4f4d<\/td>\n<td>4KB<\/td>\n<\/tr>\n<tr>\n<td>3\u7ea7<\/td>\n<td>512\/512\/512<\/td>\n<td>2MB<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"excerpt":{"rendered":"<p>\u4e4b\u524d\u4e00\u7bc7\u6587\u7ae0\u5173\u4e8e\u5f80NetBSD\u6dfb\u52a0\u7cfb\u7edf\u8c03\u7528\uff0c\u662f\u4e3a\u4e86\u505a\u8fd9\u4e2a\u5b9e\u9a8c\u51c6\u5907\u7684\u3002 \u60f3\u8981\u7814\u7a76x86\u67b6\u6784\u4e0b\u7684\u5185\u5b58\u7ba1\u7406\uff0c\u6700\u91cd\u8981\u7684 &hellip; <a href=\"https:\/\/blog.sorayuki.net\/?p=551\" class=\"more-link\">\u7ee7\u7eed\u9605\u8bfb<span class=\"screen-reader-text\">x86\u903b\u8f91\u5730\u5740\u8f6c\u7269\u7406\u5730\u5740\u5b9e\u9a8c<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[20],"tags":[],"class_list":["post-551","post","type-post","status-publish","format-standard","hentry","category-20"],"_links":{"self":[{"href":"https:\/\/blog.sorayuki.net\/index.php?rest_route=\/wp\/v2\/posts\/551","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.sorayuki.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.sorayuki.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.sorayuki.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.sorayuki.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=551"}],"version-history":[{"count":0,"href":"https:\/\/blog.sorayuki.net\/index.php?rest_route=\/wp\/v2\/posts\/551\/revisions"}],"wp:attachment":[{"href":"https:\/\/blog.sorayuki.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=551"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.sorayuki.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=551"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.sorayuki.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=551"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}