linux-stable.git/drivers/mtd/ubi, branch linux-2.6.36.y

UBI: do not oops when erroneous PEB is scheduled for scrubbing

2010-08-30T10:32:31+00:00

When an erroneous PEB is scheduling for scrubbing, we end up with the
following oops:

[] (prot_queue_del+0x0/0x50) from [] (ubi_wl_scrub_peb+0xec/0x13c)
[] (ubi_wl_scrub_peb+0x0/0x13c) from [] (ubi_eba_read_leb+0x200/0x428)
[] (ubi_eba_read_leb+0x0/0x428) from [] (ubi_leb_read+0xe8/0x138)
[] (ubi_leb_read+0x0/0x138) from [] (ubifs_start_scan+0x7c/0xf4)
[] (ubifs_start_scan+0x0/0xf4) from [] (ubifs_recover_leb+0x3c/0x730)
[] (ubifs_recover_leb+0x0/0x730) from [] (ubifs_recover_log_leb+0xc8/0x2dc)
[] (ubifs_recover_log_leb+0x0/0x2dc) from [] (ubifs_replay_journal+0xb90/0x13a4)
[] (ubifs_replay_journal+0x0/0x13a4) from [] (ubifs_fill_super+0xb84/0x1054)
[] (ubifs_fill_super+0x0/0x1054) from [] (ubifs_get_sb+0xc4/0x2ac)
[] (ubifs_get_sb+0x0/0x2ac) from [] (vfs_kern_mount+0x58/0x94)
[] (vfs_kern_mount+0x0/0x94) from [] (do_kern_mount+0x40/0xe8)
[] (do_kern_mount+0x0/0xe8) from [] (do_new_mount+0x68/0x8c)
[] (do_new_mount+0x0/0x8c) from [] (do_mount+0x15c/0x1b8)
[] (do_mount+0x0/0x1b8) from [] (sys_mount+0x8c/0xd4)
[] (sys_mount+0x0/0xd4) from [] (ret_fast_syscall+0x0/0x2c)
Kernel panic - not syncing: Fatal exception

The problem is that 'ubi_wl_scrub_peb()' does not expect that PEBs may
be in the erroneous tree, which is a bug. This patch fixes the bug
and adds corresponding check to 'ubi_wl_scrub_peb()'. Now it will simply
ignore erroneous PEBs, instead of causing an oops.

Reported-by: Matthieu CASTET 
Signed-off-by: Artem Bityutskiy

UBI: fix kconfig unmet dependency

2010-08-30T10:31:34+00:00

warning: (OPTPROBES && KPROBES && HAVE_OPTPROBES && !PREEMPT && DEBUG_KERNEL ||
MTD_UBI_DEBUG && MTD && SYSFS && MTD_UBI || UBIFS_FS_DEBUG && MISC_FILESYSTEMS &&
UBIFS_FS || LOCKDEP && DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT &&
STACKTRACE_SUPPORT && LOCKDEP_SUPPORT || LATENCYTOP && HAVE_LATENCYTOP_SUPPORT &&
DEBUG_KERNEL && STACKTRACE_SUPPORT && PROC_FS) selects KALLSYMS_ALL
which has unmet direct dependencies (DEBUG_KERNEL && KALLSYMS)

Signed-off-by: Randy Dunlap 
Signed-off-by: Artem Bityutskiy

UBI: fix forward compatibility

2010-08-30T07:19:11+00:00

Commit 0798cea8c2e1afee59686c51d27d0e96b05e42d1 "UBI: improve corrupted flash handling"
broke delet-compatible volumes handling - it introduced a limit of 8 eraseblocks which
may be corrupted. And delete-compatible eraseblocks are added to the "corrupted" list,
so if we'd have a large delete-compatible volume, UBI would refuse it.

The fix is to add delete-compatible volumes to the erase list instead. Indeed, they are
corrupted, we just have to erase them.

Signed-off-by: Artem Bityutskiy

UBI: eliminate update of list_for_each_entry loop cursor

2010-08-30T07:19:11+00:00

list_for_each_entry uses its first argument to move from one element to the
next, so modifying it can break the iteration.  The variable re1 is already
used within the loop as a temporary variable, and is not live here.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// 
@r@
iterator name list_for_each_entry;
expression x,E;
position p1,p2;
@@

list_for_each_entry@p1(x,...) { <... x =@p2 E ...> }

@@
expression x,E;
position r.p1,r.p2;
statement S;
@@

*x =@p2 E
...
list_for_each_entry@p1(x,...) S
// 

Signed-off-by: Julia Lawall 
Signed-off-by: Artem Bityutskiy

UBI: do not warn unnecessarily

2010-08-02T04:21:19+00:00

Currently, when UBI attaches an MTD device and cannot reserve all 1% (by
default) of PEBs for bad eraseblocks handling, it prints a warning. However,
Matthew L. Creech  is not very happy to see this warning,
because he did reserve enough of PEB at the beginning, but with time some
PEBs became bad. The warning is not necessary in this case.

This patch makes UBI print the warning
 o if this is a new image
 o of this is used image and the amount of reserved PEBs is only 10% (or less)
   of the size of the reserved PEB pool.

Signed-off-by: Artem Bityutskiy

UBI: do not print message about corruptes PEBs if we have none of them

2010-08-02T04:21:19+00:00

Currently UBI prints

UBI: corrupted PEBs will be formatted

even if there are not corrupted PEBs. Fix this.

Signed-off-by: Artem Bityutskiy

UBI: improve delete-compatible volumes handling

2010-06-16T06:39:49+00:00

When a delete-compatible volume is found, it is first added to the
'corr' list, which contains "corrupted" PEBs which should be erased,
and then it is added to the used volumes tree. However, the second
step should not be done. This does not cause problems in practice,
because we never access delete-compattible volumes, but it is still
not the right thing to do.

[Artem: amended the commit message and few prints]

Signed-off-by: Brijesh Singh 
Signed-off-by: Artem Bityutskiy

UBI: fix error message and compilation warnings

2010-06-14T05:47:49+00:00

Fix the followong compilation warnings introduced by commit
095751a6e0838a712393a74eb0b7b6559dbdbe81:

drivers/mtd/ubi/scan.c: In function 'check_what_we_have':
drivers/mtd/ubi/scan.c:960: warning: passing argument 1 of 'get_random_bytes' discards qualifiers from pointer target type

Fix the following compilation warnings introduced by commit
1a49af2ca019dcb4614c32f832bbcb814b61409c:

drivers/mtd/ubi/io.c: In function 'ubi_io_read':
drivers/mtd/ubi/io.c:153: warning: initialization makes integer from pointer without a cast
drivers/mtd/ubi/io.c:170: warning: format '%s' expects type 'char *', but argument 5 has type 'int'
drivers/mtd/ubi/io.c:177: warning: format '%zd' expects type 'signed size_t', but argument 7 has type 'int'
drivers/mtd/ubi/io.c:177: warning: too many arguments for format

Also, amend the ECC error code string and add brackets and whitespace
there - this should make the message readable.

Reported-by: Stephen Rothwell 
Signed-off-by: Artem Bityutskiy

UBI: generate random image_seq when formatting MTD devices

2010-06-11T14:23:37+00:00

Generate random image_seq when attaching empty MTD device (kernel do the
ubi formating).

Signed-off-by: Matthieu CASTET 
Signed-off-by: Artem Bityutskiy

UBI: improve ECC error message

2010-06-11T14:23:37+00:00

ECC errors are quite typical errors on NAND, so it is worth improving
the UBI message and print something like

ubi_io_read: error -74 (ECC error) while reading 4096 bytes from PEB 1:4 ...

rather than

ubi_io_read: error -74 while reading 4096 bytes from PEB 1:4 ...

Signed-off-by: Artem Bityutskiy