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-rw-r--r--Documentation/BUG-HUNTING22
1 files changed, 11 insertions, 11 deletions
diff --git a/Documentation/BUG-HUNTING b/Documentation/BUG-HUNTING
index 35f5bd243336..6c816751b868 100644
--- a/Documentation/BUG-HUNTING
+++ b/Documentation/BUG-HUNTING
@@ -53,7 +53,7 @@ Finding it the old way
53 53
54[Sat Mar 2 10:32:33 PST 1996 KERNEL_BUG-HOWTO lm@sgi.com (Larry McVoy)] 54[Sat Mar 2 10:32:33 PST 1996 KERNEL_BUG-HOWTO lm@sgi.com (Larry McVoy)]
55 55
56This is how to track down a bug if you know nothing about kernel hacking. 56This is how to track down a bug if you know nothing about kernel hacking.
57It's a brute force approach but it works pretty well. 57It's a brute force approach but it works pretty well.
58 58
59You need: 59You need:
@@ -66,12 +66,12 @@ You will then do:
66 66
67 . Rebuild a revision that you believe works, install, and verify that. 67 . Rebuild a revision that you believe works, install, and verify that.
68 . Do a binary search over the kernels to figure out which one 68 . Do a binary search over the kernels to figure out which one
69 introduced the bug. I.e., suppose 1.3.28 didn't have the bug, but 69 introduced the bug. I.e., suppose 1.3.28 didn't have the bug, but
70 you know that 1.3.69 does. Pick a kernel in the middle and build 70 you know that 1.3.69 does. Pick a kernel in the middle and build
71 that, like 1.3.50. Build & test; if it works, pick the mid point 71 that, like 1.3.50. Build & test; if it works, pick the mid point
72 between .50 and .69, else the mid point between .28 and .50. 72 between .50 and .69, else the mid point between .28 and .50.
73 . You'll narrow it down to the kernel that introduced the bug. You 73 . You'll narrow it down to the kernel that introduced the bug. You
74 can probably do better than this but it gets tricky. 74 can probably do better than this but it gets tricky.
75 75
76 . Narrow it down to a subdirectory 76 . Narrow it down to a subdirectory
77 77
@@ -81,27 +81,27 @@ You will then do:
81 directories: 81 directories:
82 82
83 Copy the non-working directory next to the working directory 83 Copy the non-working directory next to the working directory
84 as "dir.63". 84 as "dir.63".
85 One directory at time, try moving the working directory to 85 One directory at time, try moving the working directory to
86 "dir.62" and mv dir.63 dir"time, try 86 "dir.62" and mv dir.63 dir"time, try
87 87
88 mv dir dir.62 88 mv dir dir.62
89 mv dir.63 dir 89 mv dir.63 dir
90 find dir -name '*.[oa]' -print | xargs rm -f 90 find dir -name '*.[oa]' -print | xargs rm -f
91 91
92 And then rebuild and retest. Assuming that all related 92 And then rebuild and retest. Assuming that all related
93 changes were contained in the sub directory, this should 93 changes were contained in the sub directory, this should
94 isolate the change to a directory. 94 isolate the change to a directory.
95 95
96 Problems: changes in header files may have occurred; I've 96 Problems: changes in header files may have occurred; I've
97 found in my case that they were self explanatory - you may 97 found in my case that they were self explanatory - you may
98 or may not want to give up when that happens. 98 or may not want to give up when that happens.
99 99
100 . Narrow it down to a file 100 . Narrow it down to a file
101 101
102 - You can apply the same technique to each file in the directory, 102 - You can apply the same technique to each file in the directory,
103 hoping that the changes in that file are self contained. 103 hoping that the changes in that file are self contained.
104 104
105 . Narrow it down to a routine 105 . Narrow it down to a routine
106 106
107 - You can take the old file and the new file and manually create 107 - You can take the old file and the new file and manually create
@@ -130,7 +130,7 @@ You will then do:
130 that makes the difference. 130 that makes the difference.
131 131
132Finally, you take all the info that you have, kernel revisions, bug 132Finally, you take all the info that you have, kernel revisions, bug
133description, the extent to which you have narrowed it down, and pass 133description, the extent to which you have narrowed it down, and pass
134that off to whomever you believe is the maintainer of that section. 134that off to whomever you believe is the maintainer of that section.
135A post to linux.dev.kernel isn't such a bad idea if you've done some 135A post to linux.dev.kernel isn't such a bad idea if you've done some
136work to narrow it down. 136work to narrow it down.