diff options
| author | Andrew Morton <akpm@linux-foundation.org> | 2007-08-24 16:11:54 -0700 |
|---|---|---|
| committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2008-04-28 10:23:31 +1000 |
| commit | f7bd32367846ba3831476e0166c9867b9b6b6103 (patch) | |
| tree | 323e3e2676c549c0da9e7542dde25cd47b105345 /fs | |
| parent | c97f117e2ecaa6a5284c7d903db61c7dab8ebc06 (diff) | |
sysfs: crash debugging
Print the name of the last-accessed sysfs file when we oops, to help track
down oopses which occur in sysfs store/read handlers. Because these oopses
tend to not leave any trace of the offending code in the stack traces.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/sysfs/file.c | 13 | ||||
| -rw-r--r-- | fs/sysfs/mount.c | 2 | ||||
| -rw-r--r-- | fs/sysfs/sysfs.h | 1 |
3 files changed, 15 insertions, 1 deletions
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index ade9a7e6a757..54e148241f43 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -18,10 +18,18 @@ #include <linux/poll.h> #include <linux/list.h> #include <linux/mutex.h> +#include <linux/limits.h> #include <asm/uaccess.h> #include "sysfs.h" +/* used in crash dumps to help with debugging */ +static char last_sysfs_file[PATH_MAX]; +void sysfs_printk_last_file(void) +{ + printk(KERN_EMERG "last sysfs file: %s\n", last_sysfs_file); +} + /* * There's one sysfs_buffer for each open file and one * sysfs_open_dirent for each sysfs_dirent with one or more open @@ -327,6 +335,11 @@ static int sysfs_open_file(struct inode *inode, struct file *file) struct sysfs_buffer *buffer; struct sysfs_ops *ops; int error = -EACCES; + char *p; + + p = d_path(&file->f_path, last_sysfs_file, sizeof(last_sysfs_file)); + if (p) + memmove(last_sysfs_file, p, strlen(p) + 1); /* need attr_sd for attr and ops, its parent for kobj */ if (!sysfs_get_active_two(attr_sd)) diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c index 74168266cd59..a3410d6b34a7 100644 --- a/fs/sysfs/mount.c +++ b/fs/sysfs/mount.c @@ -22,7 +22,7 @@ /* Random magic number */ #define SYSFS_MAGIC 0x62656572 -static struct vfsmount *sysfs_mount; +struct vfsmount *sysfs_mount; struct super_block * sysfs_sb = NULL; struct kmem_cache *sysfs_dir_cachep; diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index ff17f8da9b43..52aaa8c11f92 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -91,6 +91,7 @@ struct sysfs_addrm_cxt { extern struct sysfs_dirent sysfs_root; extern struct super_block *sysfs_sb; extern struct kmem_cache *sysfs_dir_cachep; +extern struct vfsmount *sysfs_mount; /* * dir.c |