Re: VFS: Cannot open root device "304" or hda4

From: Cédric (cedriccsm2@ifrance.com)
Date: Fri Aug 01 2003 - 10:27:49 EST


kernel_286@hotmail.com wrote:
> Hi to all, this is my first post on LKML.
>
> I'm trying 2.6.0-test2-mm2 and the compiling process ends with no errors
> except for some warnings about oss modules.
> After reboot with the 2.6 I obtain a kernel panic error:
>
> **************************************
> VFS: Cannot open root device "304" or hda4
> Please append a correct "root=" boot option
> VFS: Unable to mount root fs on hda4;
> **************************************
> I've read old ML posts but the don't help me.
> According to 2.4.21, the root fs is /dev/hda4: I've tried to give "root=0304"
> or "root=/dev/hda4" at the 2.6, but I obtain the same errors.
> I've even tried initrd with no changes.
>
> I've introduced some printk in init/do_mount.c (see the linked file at line
> 64) and before the kernel panic, the result was :
>
> ***************************************
> name hda4 - /sys/block/hda4/dev
> descriptor -1
>
> name hda - /sys/block/hda/dev
> descriptor 0
>
> scanning '3:0'
> ***************************************
>
> Is it normal?
>
> Thanks a lot.
> Mario
>
> PS: sorry for my 'bad' english.. I'm learning...
>
>
>
>
> ------------------------------------------------------------------------
>
> #include <linux/sched.h>
> #include <linux/ctype.h>
> #include <linux/fd.h>
> #include <linux/tty.h>
> #include <linux/suspend.h>
> #include <linux/root_dev.h>
> #include <linux/security.h>
>
> #include <linux/nfs_fs.h>
> #include <linux/nfs_fs_sb.h>
> #include <linux/nfs_mount.h>
>
> #include "do_mounts.h"
>
> extern int get_filesystem_list(char * buf);
>
> int __initdata rd_doload; /* 1 = load RAM disk, 0 = don't load */
>
> int root_mountflags = MS_RDONLY | MS_VERBOSE;
> char * __initdata root_device_name;
> static char __initdata saved_root_name[64];
>
> /* this is initialized in init/main.c */
> dev_t ROOT_DEV;
>
> static int __init load_ramdisk(char *str)
> {
> rd_doload = simple_strtol(str,NULL,0) & 3;
> return 1;
> }
> __setup("load_ramdisk=", load_ramdisk);
>
> static int __init readonly(char *str)
> {
> if (*str)
> return 0;
> root_mountflags |= MS_RDONLY;
> return 1;
> }
>
> static int __init readwrite(char *str)
> {
> if (*str)
> return 0;
> root_mountflags &= ~MS_RDONLY;
> return 1;
> }
>
> __setup("ro", readonly);
> __setup("rw", readwrite);
>
> static dev_t __init try_name(char *name, int part)
> {
> char path[64];
> char buf[32];
> int range;
> dev_t res;
> char *s;
> int len;
> int fd;
> unsigned int maj, min;
>
> /* read device number from .../dev */
>
> sprintf(path, "/sys/block/%s/dev", name);
> printk("name %s - path %s\n",name, path);
> fd = open(path, 0, 0);
> printk("descriptor %d\n",fd);
> if (fd < 0)
> goto fail;
> len = read(fd, buf, 32);
> close(fd);
> if (len <= 0 || len == 32 || buf[len - 1] != '\n')
> goto fail;
> buf[len - 1] = '\0';
> /*
> * The format of dev is now %u:%u -- see print_dev_t()
> */
> printk("scanning `%s'\n", buf);
> if (sscanf(buf, "%u:%u", &maj, &min) == 2)
> res = MKDEV(maj, min);
> else
> goto fail;
>
> /* if it's there and we are not looking for a partition - that's it */
> if (!part)
> return res;
>
> /* otherwise read range from .../range */
> sprintf(path, "/sys/block/%s/range", name);
> fd = open(path, 0, 0);
> if (fd < 0)
> goto fail;
> len = read(fd, buf, 32);
> close(fd);
> if (len <= 0 || len == 32 || buf[len - 1] != '\n')
> goto fail;
> buf[len - 1] = '\0';
> range = simple_strtoul(buf, &s, 10);
> if (*s)
> goto fail;
>
> /* if partition is within range - we got it */
> if (part < range)
> return res + part;
> fail:
> return (dev_t) 0;
> }
>
> /*
> * Convert a name into device number. We accept the following variants:
> *
> * 1) device number in hexadecimal represents itself
> * 2) /dev/nfs represents Root_NFS (0xff)
> * 3) /dev/<disk_name> represents the device number of disk
> * 4) /dev/<disk_name><decimal> represents the device number
> * of partition - device number of disk plus the partition number
> * 5) /dev/<disk_name>p<decimal> - same as the above, that form is
> * used when disk name of partitioned disk ends on a digit.
> *
> * If name doesn't have fall into the categories above, we return 0.
> * Driverfs is used to check if something is a disk name - it has
> * all known disks under bus/block/devices. If the disk name
> * contains slashes, name of driverfs node has them replaced with
> * dots. try_name() does the actual checks, assuming that driverfs
> * is mounted on rootfs /sys.
> */
>
> dev_t name_to_dev_t(char *name)
> {
> char s[32];
> char *p;
> dev_t res = 0;
> int part;
>
> sys_mkdir("/sys", 0700);
> if (sys_mount("sysfs", "/sys", "sysfs", 0, NULL) < 0)
> goto out;
>
> if (strncmp(name, "/dev/", 5) != 0) {
> res = (dev_t) simple_strtoul(name, &p, 16);
> if (*p)
> goto fail;
> goto done;
> }
> name += 5;
> res = Root_NFS;
> if (strcmp(name, "nfs") == 0)
> goto done;
>
> if (strlen(name) > 31)
> goto fail;
> strcpy(s, name);
> for (p = s; *p; p++)
> if (*p == '/')
> *p = '.';
> res = try_name(s, 0);
> if (res)
> goto done;
>
> while (p > s && isdigit(p[-1]))
> p--;
> if (p == s || !*p || *p == '0')
> goto fail;
> part = simple_strtoul(p, NULL, 10);
> *p = '\0';
> res = try_name(s, part);
> if (res)
> goto done;
>
> if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
> goto fail;
> p[-1] = '\0';
> res = try_name(s, part);
> done:
> sys_umount("/sys", 0);
> out:
> sys_rmdir("/sys");
> return res;
> fail:
> res = (dev_t) 0;
> goto done;
> }
>
> static int __init root_dev_setup(char *line)
> {
> strlcpy(saved_root_name, line, sizeof(saved_root_name));
> return 1;
> }
>
> __setup("root=", root_dev_setup);
>
> static char * __initdata root_mount_data;
> static int __init root_data_setup(char *str)
> {
> root_mount_data = str;
> return 1;
> }
>
> static char * __initdata root_fs_names;
> static int __init fs_names_setup(char *str)
> {
> root_fs_names = str;
> return 1;
> }
>
> __setup("rootflags=", root_data_setup);
> __setup("rootfstype=", fs_names_setup);
>
> static void __init get_fs_names(char *page)
> {
> char *s = page;
>
> if (root_fs_names) {
> strcpy(page, root_fs_names);
> while (*s++) {
> if (s[-1] == ',')
> s[-1] = '\0';
> }
> } else {
> int len = get_filesystem_list(page);
> char *p, *next;
>
> page[len] = '\0';
> for (p = page-1; p; p = next) {
> next = strchr(++p, '\n');
> if (*p++ != '\t')
> continue;
> while ((*s++ = *p++) != '\n')
> ;
> s[-1] = '\0';
> }
> }
> *s = '\0';
> }
>
> static int __init do_mount_root(char *name, char *fs, int flags, void *data)
> {
> int err = sys_mount(name, "/root", fs, flags, data);
> if (err)
> return err;
>
> sys_chdir("/root");
> ROOT_DEV = current->fs->pwdmnt->mnt_sb->s_dev;
> printk("VFS: Mounted root (%s filesystem)%s.\n",
> current->fs->pwdmnt->mnt_sb->s_type->name,
> current->fs->pwdmnt->mnt_sb->s_flags & MS_RDONLY ?
> " readonly" : "");
> return 0;
> }
>
> void __init mount_block_root(char *name, int flags)
> {
> char *fs_names = __getname();
> char *p;
> char b[BDEVNAME_SIZE];
>
> get_fs_names(fs_names);
> retry:
> for (p = fs_names; *p; p += strlen(p)+1) {
> int err = do_mount_root(name, p, flags, root_mount_data);
> switch (err) {
> case 0:
> goto out;
> case -EACCES:
> flags |= MS_RDONLY;
> goto retry;
> case -EINVAL:
> continue;
> }
> /*
> * Allow the user to distinguish between failed open
> * and bad superblock on root device.
> */
> __bdevname(ROOT_DEV, b);
> printk("VFS: Cannot open root device \"%s\" or %s\n",
> root_device_name, b);
> printk("Please append a correct \"root=\" boot option\n");
> panic("VFS: Unable to mount root fs on %s", b);
> }
> panic("VFS: Unable to mount root fs on %s", __bdevname(ROOT_DEV, b));
> out:
> putname(fs_names);
> }
>
> #ifdef CONFIG_ROOT_NFS
> static int __init mount_nfs_root(void)
> {
> void *data = nfs_root_data();
>
> create_dev("/dev/root", ROOT_DEV, NULL);
> if (data &&
> do_mount_root("/dev/root", "nfs", root_mountflags, data) == 0)
> return 1;
> return 0;
> }
> #endif
>
> #if defined(CONFIG_BLK_DEV_RAM) || defined(CONFIG_BLK_DEV_FD)
> void __init change_floppy(char *fmt, ...)
> {
> struct termios termios;
> char buf[80];
> char c;
> int fd;
> va_list args;
> va_start(args, fmt);
> vsprintf(buf, fmt, args);
> va_end(args);
> fd = open("/dev/root", O_RDWR | O_NDELAY, 0);
> if (fd >= 0) {
> sys_ioctl(fd, FDEJECT, 0);
> close(fd);
> }
> printk(KERN_NOTICE "VFS: Insert %s and press ENTER\n", buf);
> fd = open("/dev/console", O_RDWR, 0);
> if (fd >= 0) {
> sys_ioctl(fd, TCGETS, (long)&termios);
> termios.c_lflag &= ~ICANON;
> sys_ioctl(fd, TCSETSF, (long)&termios);
> read(fd, &c, 1);
> termios.c_lflag |= ICANON;
> sys_ioctl(fd, TCSETSF, (long)&termios);
> close(fd);
> }
> }
> #endif
>
> void __init mount_root(void)
> {
> #ifdef CONFIG_ROOT_NFS
> if (MAJOR(ROOT_DEV) == UNNAMED_MAJOR) {
> if (mount_nfs_root())
> return;
>
> printk(KERN_ERR "VFS: Unable to mount root fs via NFS, trying floppy.\n");
> ROOT_DEV = Root_FD0;
> }
> #endif
> #ifdef CONFIG_BLK_DEV_FD
> if (MAJOR(ROOT_DEV) == FLOPPY_MAJOR) {
> /* rd_doload is 2 for a dual initrd/ramload setup */
> if (rd_doload==2) {
> if (rd_load_disk(1)) {
> ROOT_DEV = Root_RAM1;
> root_device_name = NULL;
> }
> } else
> change_floppy("root floppy");
> }
> #endif
> create_dev("/dev/root", ROOT_DEV, root_device_name);
> mount_block_root("/dev/root", root_mountflags);
> }
>
> /*
> * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
> */
> void __init prepare_namespace(void)
> {
> int is_floppy;
>
> mount_devfs();
>
> md_run_setup();
>
> if (saved_root_name[0]) {
> root_device_name = saved_root_name;
> ROOT_DEV = name_to_dev_t(root_device_name);
> if (strncmp(root_device_name, "/dev/", 5) == 0)
> root_device_name += 5;
> }
>
> is_floppy = MAJOR(ROOT_DEV) == FLOPPY_MAJOR;
>
> /* This has to be before mounting root, because even readonly mount of reiserfs would replay
> log corrupting stuff */
> software_resume();
>
> if (initrd_load())
> goto out;
>
> if (is_floppy && rd_doload && rd_load_disk(0))
> ROOT_DEV = Root_RAM0;
>
> mount_root();
> out:
> umount_devfs("/dev");
> sys_mount(".", "/", NULL, MS_MOVE, NULL);
> sys_chroot(".");
> security_sb_post_mountroot();
> mount_devfs_fs ();
> }
>

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This archive was generated by hypermail 2b29 : Thu Aug 07 2003 - 22:00:16 EST