Vasiliy Kulikov [Wed, 3 Aug 2011 00:52:32 +0000 (10:52 +1000)]
On thread exit shm_exit_ns() is called, it uses shm_ids(ns).rw_mutex. It
is initialized in shm_init(), but it is not called yet at the moment of
kernel threads exit. Some kernel threads are created in
do_pre_smp_initcalls(), and shm_init() is called in do_initcalls().
Static initialization of shm_ids(init_ipc_ns).rw_mutex fixes the race.
It fixes a kernel oops:
Unable to handle kernel NULL pointer dereference at virtual address 00000000
...
[<c0320090>] (__down_write_nested+0x88/0xe0) from [<c015da08>] (exit_shm+0x28/0x48)
[<c015da08>] (exit_shm+0x28/0x48) from [<c002e550>] (do_exit+0x59c/0x750)
[<c002e550>] (do_exit+0x59c/0x750) from [<c003eaac>] (____call_usermodehelper+0x13c/0x154)
[<c003eaac>] (____call_usermodehelper+0x13c/0x154) from [<c000f630>] (kernel_thread_exit+0x0/0x8)
Code: 1afffffae597c00ce58d0000e587d00c (e58cd000)
Reported-by: Manuel Lauss <manuel.lauss@googlemail.com> Reported-by: Richard Weinberger <richard@nod.at> Reported-by: Marc Zyngier <maz@misterjones.org> Tested-by: Manuel Lauss <manuel.lauss@googlemail.com> Tested-by: Richard Weinberger <richard@nod.at> Tested-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Will Drewry [Wed, 3 Aug 2011 00:52:30 +0000 (10:52 +1000)]
This patch makes two changes:
- check for trailing characters after parsing PARTNROFF=%d
- disable root_wait if a syntax error is seen
The former assures that bad input like
root=PARTUUID=<validuuid>/PARTNROFF=5abc
properly fails by attempting to parse an extra character after the
integer. If the integer is missing, sscanf will fail, but if it is
present, and there is a trailing non-nul character, then the extra
field will be parsed and the error case will be hit.
The latter assures that if rootwait has been specified, the error
message isn't flooded to the screen during rootwait's loop. Instead of
adding printk ratelimiting, root_wait was disabled. This stays true to
the rootwait goal of support asynchronous device arrival while still
providing users with helpful messages. With ratelimiting or disabling
logging on rootwait, a range of edge cases turn up where the user would
not be informed of an error properly.
Signed-off-by: Will Drewry <wad@chromium.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Will Drewry [Wed, 3 Aug 2011 00:52:30 +0000 (10:52 +1000)]
Expand root=PARTUUID=UUID syntax to support selecting a root partition by
integer offset from a known, unique partition. This approach provides
similar properties to specifying a device and partition number, but using
the UUID as the unique path prior to evaluating the offset.
For example,
root=PARTUUID=99DE9194-FC15-4223-9192-FC243948F88B/PARTNROFF=1
selects the partition with UUID 99DE.. then select the next
partition.
This change is motivated by a particular usecase in Chromium OS where the
bootloader can easily determine what partition it is on (by UUID) but
doesn't perform general partition table walking.
That said, support for this model provides a direct mechanism for the user
to modify the root partition to boot without specifically needing to
extract each UUID or update the bootloader explicitly when the root
partition UUID is changed (if it is recreated to be larger, for instance).
Pinning to a /boot-style partition UUID allows the arbitrary root
partition reconfiguration/modifications with slightly less ambiguity than
just [dev][partition] and less stringency than the specific root partition
UUID.
Signed-off-by: Will Drewry <wad@chromium.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joe Thornber [Tue, 9 Aug 2011 23:13:35 +0000 (09:13 +1000)]
Initial EXPERIMENTAL implementation of device-mapper thin provisioning
with snapshot support. The 'thin' target is used to create instances of
the virtual devices that are hosted in the 'thin-pool' target. The
thin-pool target provides data sharing among devices. This sharing is
made possible using the persistent-data library in the previous patch.
The main highlight of this implementation, compared to the previous
implementation of snapshots, is that it allows many virtual devices to
be stored on the same data volume, simplifying administration and
allowing sharing of data between volumes (thus reducing disk usage).
Another big feature is support for arbitrary depth of recursive
snapshots (snapshots of snapshots of snapshots ...). The previous
implementation of snapshots did this by chaining together lookup tables,
and so performance was O(depth). This new implementation uses a single
data structure so we don't get this degradation with depth.
For further information and examples of how to use this, please read
Documentation/device-mapper/thin-provisioning.txt
Signed-off-by: Joe Thornber <thornber@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Tue, 9 Aug 2011 23:13:33 +0000 (09:13 +1000)]
This patch introduces dm_kcopyd_zero() to make it easy to use
kcopyd to write zeros into the requested areas instead
instead of copying. It is implemented by passing a NULL
copying source to dm_kcopyd_copy().
The forthcoming thin provisioning target uses this.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Milan Broz [Tue, 9 Aug 2011 23:13:33 +0000 (09:13 +1000)]
If optional discard support in dm-crypt is enabled, discards requests
bypass the crypt queue and blocks of the underlying device are discarded.
For the read path, discarded blocks are handled the same as normal
ciphertext blocks, thus decrypted.
So if the underlying device announces discarded regions return zeroes,
dm-crypt must disable this flag because after decryption there is just
random noise instead of zeroes.
Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Jonthan Brassow [Tue, 9 Aug 2011 23:13:33 +0000 (09:13 +1000)]
Fix off-by-one error in validation of write_mostly.
The user-supplied value given for the 'write_mostly' argument must be an
index starting at 0. The validation of the supplied argument failed to
check for 'N' ('>' vs '>='), which would have caused an access beyond the
end of the array.
Reported-by: Doug Ledford <dledford@redhat.com> Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Sage Weil [Tue, 9 Aug 2011 22:05:07 +0000 (15:05 -0700)]
libceph: warn on msg allocation failures
Any non-masked msg allocation failure should generate a warning and stack
trace to the console. All of these need to eventually be replaced by
safe preallocation or msgpools.
Sage Weil [Tue, 9 Aug 2011 22:03:46 +0000 (15:03 -0700)]
libceph: don't complain on msgpool alloc failures
The pool allocation failures are masked by the pool; there is no need to
spam the console about them. (That's the whole point of having the pool
in the first place.)
Mark msg allocations whose failure is safely handled as such.
Sage Weil [Thu, 4 Aug 2011 15:21:30 +0000 (08:21 -0700)]
ceph: implement (optional) max read size
The 'rsize' mount option limits the maximum size of an individual
read(ahead) operation that is sent off to an OSD. This is distinct from
'rasize', which controls the size of the readahead window.
projects / karo-tx-linux.git / log