I tried to use dump_stack to dump the calling trace in the kernel. What I did is adding a dump_stack() call in the sys_open function.
Below is the dump out result: Jul 28 17:33:31 normal kernel: [<c0151601>] sys_open+0xa6/0xb7 Jul 28 17:33:31 normal kernel: [<c0108e2c>] syscall_call+0x7/0xb However, if I insert a new kernel module which does nothing but pointing the orignal sys_open to our_sys_open(), and in our_system_open(), I simply do return sys_open(); I supprisely noticed that the dump_stack results are quite different! Why did I get the calling traces below our_ssy_open() and above syscall_call()? Any thought on this? Many thanks! Jul 28 17:33:42 normal kernel: [<c0151601>] sys_open+0xa6/0xb7 Jul 28 17:33:42 normal kernel: [<d080f02c>] our_sys_open+0x2c/0x33 [trace] Jul 28 17:33:42 normal kernel: [<c0114984>] __wake_up+0x41/0x81 Jul 28 17:33:42 normal kernel: [<c02c5e44>] sbf_read+0x5a/0x6f Jul 28 17:33:42 normal kernel: [<c01c4e12>] journal_stop+0x159/0x279 Jul 28 17:33:42 normal kernel: [<c01b7aff>] ext3_mark_iloc_dirty+0x25/0x2f Jul 28 17:33:42 normal kernel: [<c02c5e44>] sbf_read+0x5a/0x6f Jul 28 17:33:42 normal kernel: [<c01b7bef>] ext3_mark_inode_dirty+0x3d/0x44 Jul 28 17:33:42 normal kernel: [<c02c5e44>] sbf_read+0x5a/0x6f Jul 28 17:33:42 normal kernel: [<c01c583a>] __journal_file_buffer+0xbb/0x282 Jul 28 17:33:42 normal kernel: [<c01546ed>] bh_lru_install+0xc3/0xdf Jul 28 17:33:42 normal kernel: [<c01c4169>] do_get_write_access+0x36f/0x5ea Jul 28 17:33:42 normal kernel: [<c01c583a>] __journal_file_buffer+0xbb/0x282 Jul 28 17:33:42 normal kernel: [<c01c4a39>] journal_dirty_metadata+0xf4/0x16d Jul 28 17:33:42 normal kernel: [<c0114984>] __wake_up+0x41/0x81 Jul 28 17:33:42 normal kernel: [<c01c4e12>] journal_stop+0x159/0x279 Jul 28 17:33:42 normal kernel: [<c01b7aff>] ext3_mark_iloc_dirty+0x25/0x2f Jul 28 17:33:42 normal kernel: [<c01b7bef>] ext3_mark_inode_dirty+0x3d/0x44 Jul 28 17:33:42 normal kernel: [<c01bc111>] __ext3_journal_stop+0x1e/0x44 Jul 28 17:33:42 normal kernel: [<c01b7c5c>] ext3_dirty_inode+0x66/0x7b Jul 28 17:33:42 normal kernel: [<c01736fc>] __mark_inode_dirty+0xec/0x1ce Jul 28 17:33:42 normal kernel: [<c011cbd4>] current_fs_time+0x4d/0x5b Jul 28 17:33:42 normal kernel: [<c0107606>] __switch_to+0x2a/0x365 Jul 28 17:33:42 normal kernel: [<c0107606>] __switch_to+0x2a/0x365 Jul 28 17:33:42 normal kernel: [<c0132c3d>] find_get_page+0x30/0x6a Jul 28 17:33:42 normal kernel: [<c015f35b>] do_lookup+0x24/0x89 Jul 28 17:33:42 normal kernel: [<c01686fc>] dput+0x95/0x252 Jul 28 17:33:42 normal kernel: [<c015ff9d>] link_path_walk+0xbdd/0xe86 Jul 28 17:33:42 normal kernel: [<c0121778>] free_uid+0x1c/0x6d Jul 28 17:33:42 normal kernel: [<c01e63de>] copy_to_user+0x3c/0x4a Jul 28 17:33:42 normal kernel: [<c015b519>] cp_new_stat64+0xf5/0x105 Jul 28 17:33:42 normal kernel: [<c015b55a>] sys_stat64+0x31/0x36 Jul 28 17:33:42 normal kernel: [<c0108e2c>] syscall_call+0x7/0xb - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
