From mboxrd@z Thu Jan 1 00:00:00 1970 From: dk-arm-linux@gmx.de (Dieter Kiermaier) Date: Fri, 6 Nov 2009 15:59:47 +0100 Subject: kirkwood / openrd: umount problem using mdev (busybox) Message-ID: <200911061559.47922.dk-arm-linux@gmx.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi all, I've encountered a new problem with regards to busybox mdev while umounting a usb pendrive: I'm using kernel sh-3.2# uname -a Linux DB88FXX81 2.6.32-rc4 #2 PREEMPT Thu Nov 5 13:41:41 CET 2009 armv5tel GNU/Linux sh-3.2# Mounting and umounting manually works like a charm without any problems. But if I disconnected a mounted pendrive and wants mdev to umount it on a remove event the umount call hangs until I get a message from my kernel (see below). A strace of the umount call gives: execve("/bin/umount", ["umount", "-f", "-l", "/dev/sda1"], [/* 14 vars */]) = 0 brk(0) = 0xf5000 uname({sys="Linux", node="DB88FXX81", ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x4001d000 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory) open("/etc/ld.so.cache", O_RDONLY) = -1 ENOENT (No such file or directory) open("/lib/tls/v5l/fast-mult/half/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls/v5l/fast-mult/half", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/tls/v5l/fast-mult/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls/v5l/fast-mult", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/tls/v5l/half/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls/v5l/half", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/tls/v5l/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls/v5l", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/tls/fast-mult/half/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls/fast-mult/half", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/tls/fast-mult/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls/fast-mult", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/tls/half/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls/half", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/tls/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/tls", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/v5l/fast-mult/half/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/v5l/fast-mult/half", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/v5l/fast-mult/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/v5l/fast-mult", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/v5l/half/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/v5l/half", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/v5l/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/v5l", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/fast-mult/half/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/fast-mult/half", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/fast-mult/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/fast-mult", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/half/libm.so.6", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/lib/half", 0xbed722f8) = -1 ENOENT (No such file or directory) open("/lib/libm.so.6", O_RDONLY) = 4 read(4, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0(\0\1\0\0\0\0342\0\0004\0\0\0"..., 512) = 512 fstat64(4, {st_mode=S_IFREG|0755, st_size=693352, ...}) = 0 mmap2(NULL, 712856, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 4, 0) = 0x40026000 mprotect(0x400cc000, 28672, PROT_NONE) = 0 mmap2(0x400d3000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 4, 0xa5) = 0x400d3000 close(4) = 0 open("/lib/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/v5l/fast-mult/half/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls/v5l/fast-mult/half", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/v5l/fast-mult/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls/v5l/fast-mult", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/v5l/half/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls/v5l/half", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/v5l/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls/v5l", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/fast-mult/half/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls/fast-mult/half", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/fast-mult/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls/fast-mult", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/half/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls/half", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/tls/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/tls", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/v5l/fast-mult/half/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/v5l/fast-mult/half", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/v5l/fast-mult/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/v5l/fast-mult", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/v5l/half/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/v5l/half", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/v5l/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/v5l", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/fast-mult/half/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/fast-mult/half", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/fast-mult/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/fast-mult", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/half/libgcc_s.so.1", O_RDONLY) = -1 ENOENT (No such file or directory) stat64("/usr/lib/half", 0xbed722e0) = -1 ENOENT (No such file or directory) open("/usr/lib/libgcc_s.so.1", O_RDONLY) = 4 read(4, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0(\0\1\0\0\0\304\"\0\0004\0\0\0"..., 512) = 512 fstat64(4, {st_mode=S_IFREG|0644, st_size=65824, ...}) = 0 mmap2(NULL, 78540, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 4, 0) = 0x400d5000 mprotect(0x400e1000, 28672, PROT_NONE) = 0 mmap2(0x400e8000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 4, 0xb) = 0x400e8000 close(4) = 0 open("/lib/libc.so.6", O_RDONLY) = 4 read(4, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0(\0\1\0\0\0\340J\1\0004\0\0\0"..., 512) = 512 fstat64(4, {st_mode=S_IFREG|0755, st_size=1249460, ...}) = 0 mmap2(NULL, 1237404, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 4, 0) = 0x400e9000 mprotect(0x4020b000, 28672, PROT_NONE) = 0 mmap2(0x40212000, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 4, 0x121) = 0x40212000 mmap2(0x40215000, 8604, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x40215000 close(4) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x4001e000 set_tls(0x4001e720, 0x400256f4, 0x4001edf8, 0x40025058, 0x40) = 0 mprotect(0x40212000, 8192, PROT_READ) = 0 mprotect(0x400d3000, 4096, PROT_READ) = 0 getpid() = 562 getuid32() = 0 brk(0) = 0xf5000 brk(0x117000) = 0x117000 open("/proc/mounts", O_RDONLY) = 4 fstat64(4, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x4001f000 read(4, "rootfs / rootfs rw 0 0\n/dev/root"..., 1024) = 655 read(4, "", 1024) = 0 close(4) = 0 munmap(0x4001f000, 4096) = 0 lstat64("/dev", {st_mode=S_IFDIR|S_ISVTX|0777, st_size=2880, ...}) = 0 lstat64("/dev/sda1", {st_mode=S_IFBLK|0660, st_rdev=makedev(8, 1), ...}) = 0 umount("/mnt/usbdisk", 0 And after that the process hangs: sh-3.2# ps PID USER VSZ STAT COMMAND 1 root 3256 S init 2 root 0 SW [kthreadd] 3 root 0 SW [ksoftirqd/0] 4 root 0 SW [watchdog/0] 5 root 0 SW [events/0] 6 root 0 SW [khelper] 9 root 0 SW [async/mgr] 133 root 0 SW [sync_supers] 135 root 0 SW [bdi-default] 137 root 0 SW [kblockd/0] 143 root 0 SW [ata/0] 144 root 0 SW [ata_aux] 152 root 0 SW [khubd] 155 root 0 SW [kseriod] 158 root 0 SW [kmmcd] 178 root 0 SW [rpciod/0] 186 root 0 SW [khungtaskd] 187 root 0 SW [kswapd0] 236 root 0 SW [aio/0] 244 root 0 SW [nfsiod] 250 root 0 SW [crypto/0] 387 root 0 SW [scsi_eh_0] 390 root 0 SW [scsi_eh_1] 397 root 0 SW [mtdblockd] 411 root 0 SW [orion_spi] 494 root 0 SW [usbhid_resumer] 515 root 2280 S /bin/sh /sbin/mini_httpd_wrapper 516 root 2644 S -/bin/sh 519 root 2176 S /sbin/mini_httpd -D -d /var/www -u root -c **.cgi -i 527 root 0 SW [scsi_eh_2] 550 root 3264 S /sbin/mdev block 554 root 2604 S /bin/sh /sbin/mdev_mount_usbdisk.sh 561 root 1836 S strace umount -f -l /dev/sda1 562 root 3260 D umount -f -l /dev/sda1 564 root 3260 R ps sh-3.2# After a while I get this from my kernel every now and then: sh-3.2# INFO: task umount:562 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. umount D c03467c0 0 562 561 0x00000100 [] (schedule+0x360/0x3f0) from [] (bdi_sched_wait+0xc/0x18) [] (bdi_sched_wait+0xc/0x18) from [] (__wait_on_bit+0x60/0xac) [] (__wait_on_bit+0x60/0xac) from [] (out_of_line_wait_on_bit+0x74/0x80) [] (out_of_line_wait_on_bit+0x74/0x80) from [] (sync_inodes_sb+0x88/0x17c) [] (sync_inodes_sb+0x88/0x17c) from [] (__sync_filesystem+0x30/0x6c) [] (__sync_filesystem+0x30/0x6c) from [] (generic_shutdown_super+0x2c/0x130) [] (generic_shutdown_super+0x2c/0x130) from [] (kill_block_super+0x1c/0x38) [] (kill_block_super+0x1c/0x38) from [] (deactivate_super+0x68/0x8c) [] (deactivate_super+0x68/0x8c) from [] (sys_umount+0x2c8/0x2fc) [] (sys_umount+0x2c8/0x2fc) from [] (__sys_trace_return+0x0/0x24) Any help would be welcome! Many thanks, Dieter