hwpoison-inject.c 2.6 KB

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  1. // SPDX-License-Identifier: GPL-2.0-only
  2. /* Inject a hwpoison memory failure on a arbitrary pfn */
  3. #include <linux/module.h>
  4. #include <linux/debugfs.h>
  5. #include <linux/kernel.h>
  6. #include <linux/mm.h>
  7. #include <linux/swap.h>
  8. #include <linux/pagemap.h>
  9. #include <linux/hugetlb.h>
  10. #include "internal.h"
  11. static struct dentry *hwpoison_dir;
  12. static int hwpoison_inject(void *data, u64 val)
  13. {
  14. unsigned long pfn = val;
  15. struct page *p;
  16. struct page *hpage;
  17. int err;
  18. if (!capable(CAP_SYS_ADMIN))
  19. return -EPERM;
  20. if (!pfn_valid(pfn))
  21. return -ENXIO;
  22. p = pfn_to_page(pfn);
  23. hpage = compound_head(p);
  24. if (!hwpoison_filter_enable)
  25. goto inject;
  26. shake_page(hpage, 0);
  27. /*
  28. * This implies unable to support non-LRU pages.
  29. */
  30. if (!PageLRU(hpage) && !PageHuge(p))
  31. return 0;
  32. /*
  33. * do a racy check to make sure PG_hwpoison will only be set for
  34. * the targeted owner (or on a free page).
  35. * memory_failure() will redo the check reliably inside page lock.
  36. */
  37. err = hwpoison_filter(hpage);
  38. if (err)
  39. return 0;
  40. inject:
  41. pr_info("Injecting memory failure at pfn %#lx\n", pfn);
  42. return memory_failure(pfn, 0);
  43. }
  44. static int hwpoison_unpoison(void *data, u64 val)
  45. {
  46. if (!capable(CAP_SYS_ADMIN))
  47. return -EPERM;
  48. return unpoison_memory(val);
  49. }
  50. DEFINE_DEBUGFS_ATTRIBUTE(hwpoison_fops, NULL, hwpoison_inject, "%lli\n");
  51. DEFINE_DEBUGFS_ATTRIBUTE(unpoison_fops, NULL, hwpoison_unpoison, "%lli\n");
  52. static void pfn_inject_exit(void)
  53. {
  54. debugfs_remove_recursive(hwpoison_dir);
  55. }
  56. static int pfn_inject_init(void)
  57. {
  58. hwpoison_dir = debugfs_create_dir("hwpoison", NULL);
  59. /*
  60. * Note that the below poison/unpoison interfaces do not involve
  61. * hardware status change, hence do not require hardware support.
  62. * They are mainly for testing hwpoison in software level.
  63. */
  64. debugfs_create_file("corrupt-pfn", 0200, hwpoison_dir, NULL,
  65. &hwpoison_fops);
  66. debugfs_create_file("unpoison-pfn", 0200, hwpoison_dir, NULL,
  67. &unpoison_fops);
  68. debugfs_create_u32("corrupt-filter-enable", 0600, hwpoison_dir,
  69. &hwpoison_filter_enable);
  70. debugfs_create_u32("corrupt-filter-dev-major", 0600, hwpoison_dir,
  71. &hwpoison_filter_dev_major);
  72. debugfs_create_u32("corrupt-filter-dev-minor", 0600, hwpoison_dir,
  73. &hwpoison_filter_dev_minor);
  74. debugfs_create_u64("corrupt-filter-flags-mask", 0600, hwpoison_dir,
  75. &hwpoison_filter_flags_mask);
  76. debugfs_create_u64("corrupt-filter-flags-value", 0600, hwpoison_dir,
  77. &hwpoison_filter_flags_value);
  78. #ifdef CONFIG_MEMCG
  79. debugfs_create_u64("corrupt-filter-memcg", 0600, hwpoison_dir,
  80. &hwpoison_filter_memcg);
  81. #endif
  82. return 0;
  83. }
  84. module_init(pfn_inject_init);
  85. module_exit(pfn_inject_exit);
  86. MODULE_LICENSE("GPL");