RepoMirrors
/
crash
mirror of https://github.com/crash-utility/crash
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Fix "kmem -i" and "swap" commands on Linux 6.10-rc1 and later kernels 

Kernel commit 798cb7f9aec3 ("swapon(2)/swapoff(2): don't bother with
block size") removed swap_info_struct.old_block_size member at Linux
6.10-rc1.  The crash-utility has used this to determine whether a swap
is a partition or file and to determine the way to get the swap path.

Withtout the patch, the "kmem -i" and "swap" commands fail with the
following error messsage:

  crash> kmem -i
  ...
     TOTAL HUGE  13179392      50.3 GB         ----
      HUGE FREE  13179392      50.3 GB  100% of TOTAL HUGE

  swap: invalid (optional) structure member offsets: swap_info_struct_swap_device or swap_info_struct_old_block_size
        FILE: memory.c  LINE: 16032  FUNCTION: dump_swap_info()

The swap_file member of recent swap_info_struct is a pointer to a
struct file (once upon a time it was dentry), use this fact directly.

Tested-by: Li Zhijian <lizhijian@fujitsu.com>
Signed-off-by: Kazuhito Hagio <k-hagio-ab@nec.com>
This commit is contained in:
HAGIO KAZUHITO(萩尾　一仁) 2024-06-11 02:40:55 +00:00 committed by Lianbo Jiang
parent 196c4b79c1
commit 3452fe802b
4 changed files with 26 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
defs.h
View File

@ -2242,6 +2242,7 @@ struct offset_table { /* stash of commonly-used offsets */
long log_caller_id;
long vmap_node_busy;
long rb_list_head;
long file_f_inode;
};
struct size_table { /* stash of commonly-used sizes */

1
filesys.c
View File

@ -2038,6 +2038,7 @@ vfs_init(void)
MEMBER_OFFSET_INIT(file_f_dentry, "file", "f_dentry");
MEMBER_OFFSET_INIT(file_f_vfsmnt, "file", "f_vfsmnt");
MEMBER_OFFSET_INIT(file_f_count, "file", "f_count");
MEMBER_OFFSET_INIT(file_f_inode, "file", "f_inode");
MEMBER_OFFSET_INIT(path_mnt, "path", "mnt");
MEMBER_OFFSET_INIT(path_dentry, "path", "dentry");
if (INVALID_MEMBER(file_f_dentry)) {

28
memory.c
View File

@ -16075,6 +16075,8 @@ dump_swap_info(ulong swapflags, ulong *totalswap_pages, ulong *totalused_pages)
char buf3[BUFSIZE];
char buf4[BUFSIZE];
char buf5[BUFSIZE];
int swap_file_is_file =
STREQ(MEMBER_TYPE_NAME("swap_info_struct", "swap_file"), "file");
if (!symbol_exists("nr_swapfiles"))
error(FATAL, "nr_swapfiles doesn't exist in this kernel!\n");
@ -16118,9 +16120,21 @@ dump_swap_info(ulong swapflags, ulong *totalswap_pages, ulong *totalused_pages)
swap_file = ULONG(vt->swap_info_struct +
OFFSET(swap_info_struct_swap_file));
swap_device = INT(vt->swap_info_struct +
OFFSET_OPTION(swap_info_struct_swap_device,
swap_info_struct_old_block_size));
/* Linux 6.10 and later */
if (INVALID_MEMBER(swap_info_struct_swap_device) &&
INVALID_MEMBER(swap_info_struct_old_block_size) &&
swap_file_is_file) {
ulong inode;
ushort mode;
readmem(swap_file + OFFSET(file_f_inode), KVADDR, &inode,
sizeof(ulong), "swap_file.f_inode", FAULT_ON_ERROR);
readmem(inode + OFFSET(inode_i_mode), KVADDR, &mode,
sizeof(ushort), "inode.i_mode", FAULT_ON_ERROR);
swap_device = S_ISBLK(mode);
} else
swap_device = INT(vt->swap_info_struct +
OFFSET_OPTION(swap_info_struct_swap_device,
swap_info_struct_old_block_size));
pages = INT(vt->swap_info_struct +
OFFSET(swap_info_struct_pages));
@ -16161,8 +16175,12 @@ dump_swap_info(ulong swapflags, ulong *totalswap_pages, ulong *totalused_pages)
OFFSET(swap_info_struct_swap_vfsmnt));
get_pathname(swap_file, buf, BUFSIZE,
1, vfsmnt);
} else if (VALID_MEMBER
(swap_info_struct_old_block_size)) {
} else if (VALID_MEMBER(swap_info_struct_old_block_size) ||
swap_file_is_file) {
/*
* Linux 6.10 and later kernels do not have old_block_size,
* but this still should work, if swap_file is file.
*/
devname = vfsmount_devname(file_to_vfsmnt(swap_file),
buf1, BUFSIZE);
get_pathname(file_to_dentry(swap_file),

1
symbols.c
View File

@ -10522,6 +10522,7 @@ dump_offset_table(char *spec, ulong makestruct)
OFFSET(file_f_count));
fprintf(fp, " file_f_path: %ld\n",
OFFSET(file_f_path));
fprintf(fp, " file_f_inode: %ld\n", OFFSET(file_f_inode));
fprintf(fp, " path_mnt: %ld\n",
OFFSET(path_mnt));
fprintf(fp, " path_dentry: %ld\n",