Before this patch, multiple users called gfs2_qa_alloc which allocated
a qadata structure to the inode, if quotas are turned on. Later, in
file close or evict, the structure was deleted with gfs2_qa_delete.
But there can be several competing processes who need access to the
structure. There were races between file close (release) and the others.
Thus, a release could delete the structure out from under a process
that relied upon its existence. For example, chown.
This patch changes the management of the qadata structures to be
a get/put scheme. Function gfs2_qa_alloc has been changed to gfs2_qa_get
and if the structure is allocated, the count essentially starts out at
1. Function gfs2_qa_delete has been renamed to gfs2_qa_put, and the
last guy to decrement the count to 0 frees the memory.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Before this patch, multiple callers called gfs2_rsqa_alloc to force
the existence of a reservations structure and a quota data structure
if needed. However, now the reservations are handled separately, so
the quota data is only the quota data. So we eliminate the one in
favor of just calling gfs2_qa_alloc directly.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Replace open-coded versions of list_first_entry and list_last_entry with those
functions.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
When allocating a new inode, mark the iopen glock holder as uninitialized to
make sure gfs2_evict_inode won't fail after an incomplete create or lookup. In
gfs2_evict_inode, allow the inode glock to be NULL and remove the duplicate
iopen glock teardown code. In gfs2_inode_lookup, don't tear down things that
gfs2_evict_inode will already tear down.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Before this patch, if gfs2_ail1_flush gets an error from function
gfs2_ail1_start_one (which comes indirectly from generic_writepages)
the file system is withdrawn, but without any explanation why.
This patch adds an error message if gfs2_ail1_flush gets an error
from gfs2_ail1_start_one.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Function leaf_dealloc was not allocating enough journal space for
revokes. Before, it allocated 'l_blocks' revokes, but it needs one
more for the revoke of the dinode that is modified. This patch adds
the needed revoke entry to function leaf_dealloc.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Before this patch, journal replays could stomp on log flushes
and each other because both log flushes and journal replays used
the same sd_log_bio. Function gfs2_log_flush prevents other log
flushes from interfering by taking the sd_log_flush_lock rwsem
during the flush. However, it does not protect against journal
replays. This patch allows the journal replay to take the same
sd_log_flush_lock rwsem so use of the sd_log_bio is not stomped.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Before this patch, function gfs2_releasepage would free any bd
elements that had been used for the page being released. However,
those bd elements may still be queued to the sd_log_revokes list,
in which case we cannot free them until the revoke has been issued.
This patch adds additional checks for bds that are still being
used for revokes.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Function gfs2_log_flush() had a few places where it tried to withdraw
from the file system when errors were encountered. The problem is,
it should delay those withdraws until the log flush lock is no longer
held.
This patch creates a new function just for delayed withdraws for
situations like this. If errors=panic was specified on mount, we
still want to do it the old fashioned way because the panic it does
not help to delay in that situation.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, function do_xmote would try to sync out the glock
dirty data by calling the appropriate glops function XXX_go_sync()
but it did not check for a good return code. If the sync was not
possible due to an io error or whatever, do_xmote would continue on
and call go_inval and release the glock to other cluster nodes.
When those nodes go to replay the journal, they may already be holding
glocks for the journal records that should have been synced, but were
not due to the ignored error.
This patch introduces proper error code checking to the go_sync
family of glops functions.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, run_queue would demote glocks based on whether
there are any more holders. But if the glock has pending revokes that
haven't been written to the media, giving up the glock might end in
file system corruption if the revokes never get written due to
io errors, node crashes and fences, etc. In that case, another node
will replay the metadata blocks associated with the glock, but
because the revoke was never written, it could replay that block
even though the glock had since been granted to another node who
might have made changes.
This patch changes the logic in run_queue so that it never demotes
a glock until its count of pending revokes reaches zero.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, gfs2_logd continually tried to flush its journal
log, after the file system is withdrawn. We don't want to write anything
to the journal, lest we add corruption. Best course of action is to
drain the ail1 into the ail2 list (via gfs2_ail1_empty) then drain the
ail2 list with a new function, ail2_drain.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, function gfs2_ail1_start_one would return any
errors it received from write_cache_pages (except -EBUSY) but it did
not withdraw. Since function gfs2_ail1_flush just checks for the bad
return code and loops, the loop might potentially never end.
This patch adds some logic to allow it to exit the loop and withdraw
properly when errors are received from write_cache_pages.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, if gfs2_ail_empty_gl saw there was nothing on
the ail list, it would return and not flush the log. The problem
is that there could still be a revoke for the rgrp sitting on the
sd_log_le_revoke list that's been recently taken off the ail list.
But that revoke still needs to be written, and the rgrp_go_inval
still needs to call log_flush_wait to ensure the revokes are all
properly written to the journal before we relinquish control of
the glock to another node. If we give the glock to another node
before we have this knowledge, the node might crash and its journal
replayed, in which case the missing revoke would allow the journal
replay to replay the rgrp over top of the rgrp we already gave to
another node, thus overwriting its changes and corrupting the
file system.
This patch makes gfs2_ail_empty_gl still call gfs2_log_flush rather
than returning.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, function do_xmote just assumed all the writes
submitted to the journal were finished and successful, and it
called the go_unlock function to release the dlm lock. But if
they're not, and a revoke failed to make its way to the journal,
a journal replay on another node will cause corruption if we
let the go_inval function continue and tell dlm to release the
glock to another node. This patch adds a couple checks for errors
in do_xmote after the calls to go_sync and go_inval. If an error
is found, we cannot withdraw yet, because the withdraw itself
uses glocks to make the file system read-only. Instead, we flag
the error. Later, asserts should cause another node to replay
the journal before continuing, thus protecting rgrp and dinode
glocks and maintaining the integrity of the metadata. Note that
we only need to do this for journaled glocks. System glocks
should be able to progress even under withdrawn conditions.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, function gfs2_end_log_write would detect any IO
errors writing to the journal and put out an appropriate message,
but it never set a withdrawing condition. Eventually, the log daemon
would see the error and determine it was time to withdraw, but in
the meantime, other processes could continue running as if nothing
bad ever happened. The biggest consequence is that __gfs2_glock_put
would BUG() when it saw that there were still unwritten items.
This patch sets the WITHDRAWING status as soon as an IO error is
detected, and that way, the BUG will be avoided so the file system
can be properly withdrawn and unmounted.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, function gfs2_write_revokes would call
gfs2_ail1_empty, then traverse the sd_ail1_list looking for
transactions that had bds which were no longer queued to a glock.
And if it found some, it would try to issue revokes for them, up to
a predetermined maximum. There were two problems with how it did
this. First was the fact that gfs2_ail1_empty moves transactions
which have nothing remaining on the ail1 list from the sd_ail1_list
to the sd_ail2_list, thus making its traversal of sd_ail1_list
miss them completely, and therefore, never issue revokes for them.
Second was the fact that there were three traversals (or partial
traversals) of the sd_ail1_list, each of which took and then
released the sd_ail_lock lock: First inside gfs2_ail1_empty,
second to determine if there are any revokes to be issued, and
third to actually issue them. All this taking and releasing of the
sd_ail_lock meant other processes could modify the lists and the
conditions in which we're working.
This patch simplies the whole process by adding a new parameter
to function gfs2_ail1_empty, max_revokes. For normal calls, this
is passed in as 0, meaning we don't want to issue any revokes.
For function gfs2_write_revokes, we pass in the maximum number
of revokes we can, thus allowing gfs2_ail1_empty to add the
revokes where needed. This simplies the code, allows for a single
holding of the sd_ail_lock, and allows gfs2_ail1_empty to add
revokes for all the necessary bd items without missing any.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, function check_journal_clean would give messages
related to journal recovery. That's fine for mount time, but when a
node withdraws and forces replay that way, we don't want all those
distracting and misleading messages. This patch adds a new parameter
to make those messages optional.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, the rgrp_go_inval and inode_go_inval functions each
checked if there were any items left on the ail count (by way of a
count), and if so, did a withdraw. But the withdraw code now uses
glocks when changing the file system to read-only status. So we can
not have glock functions withdrawing or a hang will likely result:
The glocks can't be serviced by the work_func if the work_func is
busy doing its own withdraw.
This patch removes the checks from the go_inval functions and adds
a centralized check in do_xmote to warn about the problem and not
withdraw, but flag the error so it's eventually caught when the logd
daemon eventually runs.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
When a node withdraws from a file system, it often leaves its journal
in an incomplete state. This is especially true when the withdraw is
caused by io errors writing to the journal. Before this patch, a
withdraw would try to write a "shutdown" record to the journal, tell
dlm it's done with the file system, and none of the other nodes
know about the problem. Later, when the problem is fixed and the
withdrawn node is rebooted, it would then discover that its own
journal was incomplete, and replay it. However, replaying it at this
point is almost guaranteed to introduce corruption because the other
nodes are likely to have used affected resource groups that appeared
in the journal since the time of the withdraw. Replaying the journal
later will overwrite any changes made, and not through any fault of
dlm, which was instructed during the withdraw to release those
resources.
This patch makes file system withdraws seen by the entire cluster.
Withdrawing nodes dequeue their journal glock to allow recovery.
The remaining nodes check all the journals to see if they are
clean or in need of replay. They try to replay dirty journals, but
only the journals of withdrawn nodes will be "not busy" and
therefore available for replay.
Until the journal replay is complete, no i/o related glocks may be
given out, to ensure that the replay does not cause the
aforementioned corruption: We cannot allow any journal replay to
overwrite blocks associated with a glock once it is held.
The "live" glock which is now used to signal when a withdraw
occurs. When a withdraw occurs, the node signals its withdraw by
dequeueing the "live" glock and trying to enqueue it in EX mode,
thus forcing the other nodes to all see a demote request, by way
of a "1CB" (one callback) try lock. The "live" glock is not
granted in EX; the callback is only just used to indicate a
withdraw has occurred.
Note that all nodes in the cluster must wait for the recovering
node to finish replaying the withdrawing node's journal before
continuing. To this end, it checks that the journals are clean
multiple times in a retry loop.
Also note that the withdraw function may be called from a wide
variety of situations, and therefore, we need to take extra
precautions to make sure pointers are valid before using them in
many circumstances.
We also need to take care when glocks decide to withdraw, since
the withdraw code now uses glocks.
Also, before this patch, if a process encountered an error and
decided to withdraw, if another process was already withdrawing,
the second withdraw would be silently ignored, which set it free
to unlock its glocks. That's correct behavior if the original
withdrawer encounters further errors down the road. But if
secondary waiters don't wait for the journal replay, unlocking
glocks will allow other nodes to use them, despite the fact that
the journal containing those blocks is being replayed. The
replay needs to finish before our glocks are released to other
nodes. IOW, secondary withdraws need to wait for the first
withdraw to finish.
For example, if an rgrp glock is unlocked by a process that didn't
wait for the first withdraw, a journal replay could introduce file
system corruption by replaying a rgrp block that has already been
granted to a different cluster node.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
We need to allow some glocks to be enqueued, dequeued, promoted, and demoted
when we're withdrawn. For example, to maintain metadata integrity, we should
disallow the use of inode and rgrp glocks when withdrawn. Other glocks, like
iopen or the transaction glocks may be safely used because none of their
metadata goes through the journal. So in general, we should disallow all
glocks with an address space, and allow all the others. One exception is:
we need to allow our active journal to be demoted so others may recover it.
Allowing glocks after withdraw gives us the ability to take appropriate
action (in a following patch) to have our journal properly replayed by
another node rather than just abandoning the current transactions and
pretending nothing bad happened, leaving the other nodes free to modify
the blocks we had in our journal, which may result in file system
corruption.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Before this patch function check_journal_clean was in ops_fstype.c.
This patch moves it to util.c so we can make use of it elsewhere
in a future patch.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
When a node fails, user space informs dlm of the node failure,
and dlm instructs gfs2 on the surviving nodes to perform journal
recovery. It does this by calling various callback functions in
lock_dlm.c. To mark its progress, it keeps generation numbers
and recover bits in a dlm "control" lock lvb, which is seen by
all nodes to determine which journals need to be replayed.
The gfs2 on all nodes get the same recovery requests from dlm,
so they all try to do the recovery, but only one will be
granted the exclusive lock on the journal. The others fail
with a "Busy" message on their "try lock."
However, when a node is withdrawn, it cannot safely do any
recovery or replay any journals. To make matters worse,
gfs2 might withdraw as a result of attempting recovery. For
example, this might happen if the device goes offline, or if
an hba fails. But in today's gfs2 code, it doesn't check for
being withdrawn at any step in the recovery process. What's
worse is that these callbacks from dlm have no return code,
so there is no way to indicate failure back to dlm. We can
send a "Recovery failed" uevent eventually, but that tells
user space what happened, not dlm's kernel code.
Before this patch, lock_dlm would perform its recovery steps but
ignore the result, and eventually it would still update its
generation number in the lvb, despite the fact that it may have
withdrawn or encountered an error. The other nodes would then
see the newer generation number in the lvb and conclude that
they don't need to do recovery because the generation number
is newer than the last one they saw. They think a different
node has already recovered the journal.
This patch adds checks to several of the callbacks used by dlm
in its recovery state machine so that the functions are ignored
and skipped if an io error has occurred or if the file system
is withdrawn. That prevents the lvb bits from being updated, and
therefore dlm and user space still see the need for recovery to
take place.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, all io errors received by the quota daemon or the
logd daemon would cause a complaint message to be issued, such as:
gfs2: fsid=dm-13.0: Error 10 writing to journal, jid=0
This patch changes it so that the error message is only issued the
first time the error is encountered.
Also, before this patch function gfs2_end_log_write did not set the
sd_log_error value, so log errors would not cause the file system to
be withdrawn. This patch sets the error code so the file system is
properly withdrawn if an io error is encountered writing to the journal.
WARNING: This change in function breaks check xfstests generic/441
and causes it to fail: io errors writing to the log should cause a
file system to be withdrawn, and no further operations are tolerated.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, gfs2 kept track of journal io errors in two
places sd_log_error and the SDF_AIL1_IO_ERROR flag in sd_flags.
This patch consolidates the two into sd_log_error so that it
reflects the first error encountered writing to the journal.
In future patches, we will take advantage of this by checking
this value rather than having to check both when reacting to
io errors.
In addition, this fixes a tight loop in unmount: If buffers
get on the ail1 list and an io error occurs elsewhere, the
ail1 list would never be cleared because they were always busy.
So unmount would hang, waiting for the ail1 list to empty.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, the rgrp code had a serious problem related to
how it managed buffer_heads for resource groups. The problem caused
file system corruption, especially in cases of journal replay.
When an rgrp glock was demoted to transfer ownership to a
different cluster node, do_xmote() first calls rgrp_go_sync and then
rgrp_go_inval, as expected. When it calls rgrp_go_sync, that called
gfs2_rgrp_brelse() that dropped the buffer_head reference count.
In most cases, the reference count went to zero, which is right.
However, there were other places where the buffers are handled
differently.
After rgrp_go_sync, do_xmote called rgrp_go_inval which called
gfs2_rgrp_brelse a second time, then rgrp_go_inval's call to
truncate_inode_pages_range would get rid of the pages in memory,
but only if the reference count drops to 0.
Unfortunately, gfs2_rgrp_brelse was setting bi->bi_bh = NULL.
So when rgrp_go_sync called gfs2_rgrp_brelse, it lost the pointer
to the buffer_heads in cases where the reference count was still 1.
Therefore, when rgrp_go_inval called gfs2_rgrp_brelse a second time,
it failed the check for "if (bi->bi_bh)" and thus failed to call
brelse a second time. Because of that, the reference count on those
buffers sometimes failed to drop from 1 to 0. And that caused
function truncate_inode_pages_range to keep the pages in page cache
rather than freeing them.
The next time the rgrp glock was acquired, the metadata read of
the rgrp buffers re-used the pages in memory, which were now
wrong because they were likely modified by the other node who
acquired the glock in EX (which is why we demoted the glock).
This re-use of the page cache caused corruption because changes
made by the other nodes were never seen, so the bitmaps were
inaccurate.
For some reason, the problem became most apparent when journal
replay forced the replay of rgrps in memory, which caused newer
rgrp data to be overwritten by the older in-core pages.
A big part of the problem was that the rgrp buffer were released
in multiple places: The go_unlock function would release them when
the glock was released rather than when the glock is demoted,
which is clearly wrong because our intent was to cache them until
the glock is demoted from SH or EX.
This patch attempts to clean up the mess and make one consistent
and centralized mechanism for managing the rgrp buffer_heads by
implementing several changes:
1. It eliminates the call to gfs2_rgrp_brelse() from rgrp_go_sync.
We don't want to release the buffers or zero the pointers when
syncing for the reasons stated above. It only makes sense to
release them when the glock is actually invalidated (go_inval).
And when we do, then we set the bh pointers to NULL.
2. The go_unlock function (which was only used for rgrps) is
eliminated, as we've talked about doing many times before.
The go_unlock function was called too early in the glock dq
process, and should not happen until the glock is invalidated.
3. It also eliminates the call to rgrp_brelse in gfs2_clear_rgrpd.
That will now happen automatically when the rgrp glocks are
demoted, and shouldn't happen any sooner or later than that.
Instead, function gfs2_clear_rgrpd has been modified to demote
the rgrp glocks, and therefore, free those pages, before the
remaining glocks are culled by gfs2_gl_hash_clear. This
prevents the gl_object from hanging around when the glocks are
culled.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch fixes a bug in which function gfs2_log_flush can get into
an infinite loop when a gfs2 file system is withdrawn. The problem
is the infinite loop "for (;;)" in gfs2_log_flush which would never
finish because the io error and subsequent withdraw prevented the
items from being taken off the ail list.
This patch tries to clean up the mess by allowing withdraw situations
to move not-in-flight buffer_heads to the ail2 list, where they will
be dealt with later.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
File system withdraws can be delayed when inconsistencies are
discovered when we cannot withdraw immediately, for example, when
critical spin_locks are held. But delaying the withdraw can cause
gfs2 to ignore the error and keep running for a short period of time.
For example, an rgrp glock may be dequeued and demoted while there
are still buffers that haven't been properly revoked, due to io
errors writing to the journal.
This patch introduces a new concept of a pending withdraw, which
means an inconsistency has been discovered and we need to withdraw
at the earliest possible opportunity. In these cases, we aren't
quite withdrawn yet, but we still need to not dequeue glocks and
other critical things. If we dequeue the glocks and the withdraw
results in our journal being replayed, the replay could overwrite
data that's been modified by a different node that acquired the
glock in the meantime.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
The gfs2_assert functions only print messages when the filesystem hasn't been
withdrawn yet, and they indicate whether or not they've printed something in
their return value. However, none of the callers use that information, so
simply return whether or not the assert has failed.
(The gfs2_assert functions are still backwards; they return false when an
assertion is true.)
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Change the various gfs2_consist functions to return void.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
These arguments are always passed as 0, and they are never evaluated.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
In gfs2_rgrp_verify and compute_bitstructs, make sure to report errors before
withdrawing the filesystem: otherwise, when we withdraw first and withdraw is
configured to panic, we'll never get to the error reporting.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Split gfs2_lm_withdraw into a function that prints an error message and a
function that withdraws the filesystem.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
In gfs2_file_write_iter, for direct writes, the error checking in the buffered
write fallback case is incomplete. This can cause inode write errors to go
undetected. Fix and clean up gfs2_file_write_iter along the way.
Based on a proposed fix by Christoph Hellwig <hch@lst.de>.
Fixes: 967bcc91b0 ("gfs2: iomap direct I/O support")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Set current->backing_dev_info just around the buffered write calls to
prepare for the next fix.
Fixes: 967bcc91b0 ("gfs2: iomap direct I/O support")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
When the first log header in a journal happens to have a sequence
number of 0, a bug in gfs2_find_jhead() causes it to prematurely exit,
and return an uninitialized jhead with seq 0. This can cause failures
in the caller. For instance, a mount fails in one test case.
The correct behavior is for it to continue searching through the journal
to find the correct journal head with the highest sequence number.
Fixes: f4686c26ec ("gfs2: read journal in large chunks")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
- Fix some corner cases on filesystems with a block size < page size.
- Fix a corner case that could expose incorrect access times over nfs.
- Revert an otherwise sensible revoke accounting cleanup that causes
assertion failures. The revoke accounting is whacky and needs to be
fixed properly before we can add back this cleanup.
- Various other minor cleanups.
-----BEGIN PGP SIGNATURE-----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=oo06
-----END PGP SIGNATURE-----
Merge tag 'gfs2-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 updates from Andreas Gruenbacher:
- Fix some corner cases on filesystems with a block size < page size.
- Fix a corner case that could expose incorrect access times over nfs.
- Revert an otherwise sensible revoke accounting cleanup that causes
assertion failures. The revoke accounting is whacky and needs to be
fixed properly before we can add back this cleanup.
- Various other minor cleanups.
In addition, please expect to see another pull request from Bob Peterson
about his gfs2 recovery patch queue shortly.
* tag 'gfs2-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
Revert "gfs2: eliminate tr_num_revoke_rm"
gfs2: remove unused LBIT macros
fs/gfs2: remove unused IS_DINODE and IS_LEAF macros
gfs2: Remove GFS2_MIN_LVB_SIZE define
gfs2: Fix incorrect variable name
gfs2: Avoid access time thrashing in gfs2_inode_lookup
gfs2: minor cleanup: remove unneeded variable ret in gfs2_jdata_writepage
gfs2: eliminate ssize parameter from gfs2_struct2blk
gfs2: Another gfs2_find_jhead fix
- Fix an off-by-one error when checking if offset is within inode size
-----BEGIN PGP SIGNATURE-----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=iPhi
-----END PGP SIGNATURE-----
Merge tag 'iomap-5.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull iomap fix from Darrick Wong:
"A single patch fixing an off-by-one error when we're checking to see
how far we're gotten into an EOF page"
* tag 'iomap-5.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
fs: Fix page_mkwrite off-by-one errors
Pull updates from Andrew Morton:
"Most of -mm and quite a number of other subsystems: hotfixes, scripts,
ocfs2, misc, lib, binfmt, init, reiserfs, exec, dma-mapping, kcov.
MM is fairly quiet this time. Holidays, I assume"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
kcov: ignore fault-inject and stacktrace
include/linux/io-mapping.h-mapping: use PHYS_PFN() macro in io_mapping_map_atomic_wc()
execve: warn if process starts with executable stack
reiserfs: prevent NULL pointer dereference in reiserfs_insert_item()
init/main.c: fix misleading "This architecture does not have kernel memory protection" message
init/main.c: fix quoted value handling in unknown_bootoption
init/main.c: remove unnecessary repair_env_string in do_initcall_level
init/main.c: log arguments and environment passed to init
fs/binfmt_elf.c: coredump: allow process with empty address space to coredump
fs/binfmt_elf.c: coredump: delete duplicated overflow check
fs/binfmt_elf.c: coredump: allocate core ELF header on stack
fs/binfmt_elf.c: make BAD_ADDR() unlikely
fs/binfmt_elf.c: better codegen around current->mm
fs/binfmt_elf.c: don't copy ELF header around
fs/binfmt_elf.c: fix ->start_code calculation
fs/binfmt_elf.c: smaller code generation around auxv vector fill
lib/find_bit.c: uninline helper _find_next_bit()
lib/find_bit.c: join _find_next_bit{_le}
uapi: rename ext2_swab() to swab() and share globally in swab.h
lib/scatterlist.c: adjust indentation in __sg_alloc_table
...
Summary of modules changes for the 5.6 merge window:
- Add "MS" (SHF_MERGE|SHF_STRINGS) section flags to __ksymtab_strings to
indicate to the linker that it can perform string deduplication (i.e.,
duplicate strings are reduced to a single copy in the string table).
This means any repeated namespace string would be merged to just one
entry in __ksymtab_strings.
- Various code cleanups and small fixes (fix small memleak in error path,
improve moduleparam docs, silence rcu warnings, improve error logging)
Signed-off-by: Jessica Yu <jeyu@kernel.org>
-----BEGIN PGP SIGNATURE-----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=boqg
-----END PGP SIGNATURE-----
Merge tag 'modules-for-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu:
"Summary of modules changes for the 5.6 merge window:
- Add "MS" (SHF_MERGE|SHF_STRINGS) section flags to __ksymtab_strings
to indicate to the linker that it can perform string deduplication
(i.e., duplicate strings are reduced to a single copy in the string
table). This means any repeated namespace string would be merged to
just one entry in __ksymtab_strings.
- Various code cleanups and small fixes (fix small memleak in error
path, improve moduleparam docs, silence rcu warnings, improve error
logging)"
* tag 'modules-for-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module.h: Annotate mod_kallsyms with __rcu
module: avoid setting info->name early in case we can fall back to info->mod->name
modsign: print module name along with error message
kernel/module: Fix memleak in module_add_modinfo_attrs()
export.h: reduce __ksymtab_strings string duplication by using "MS" section flags
moduleparam: fix kerneldoc
modules: lockdep: Suppress suspicious RCU usage warning
- Support mremap() for the VDSO, primarily to allow CRIU to restore the
VDSO to its checkpointed location.
- Restore the MIPS32 cBPF JIT, after having reverted the enablement of
the eBPF JIT for MIPS32 systems in the 5.5 cycle.
- Improve cop0 counter synchronization behaviour whilst onlining CPUs by
running with interrupts disabled.
- Better match FPU behaviour when emulating multiply-accumulate
instructions on pre-r6 systems that implement IEEE754-2008 style MACs.
- Loongson64 kernels now build using the MIPS64r2 ISA, allowing them to
take advantage of instructions introduced by r2.
- Support for the Ingenic X1000 SoC & the really nice little CU Neo
development board that's using it.
- Support for WMAC on GARDENA Smart Gateway devices.
- Lots of cleanup & refactoring of SGI IP27 (Origin 2*) support in
preparation for introducing IP35 (Origin 3*) support.
- Various Kconfig & Makefile cleanups.
-----BEGIN PGP SIGNATURE-----
iIwEABYIADQWIQRgLjeFAZEXQzy86/s+p5+stXUA3QUCXjRnpxYccGF1bGJ1cnRv
bkBrZXJuZWwub3JnAAoJED6nn6y1dQDdNYoA/3ZhgKX1L/hwvkPKwu7FxbL41pjB
WAm8IYDaxPvgxkcSAP9FNNepHK+oBPM8I2e3DvDvmcuYjumztdikzYbJ5HuMBA==
=MV2S
-----END PGP SIGNATURE-----
Merge tag 'mips_5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS changes from Paul Burton:
"Nothing too big or scary in here:
- Support mremap() for the VDSO, primarily to allow CRIU to restore
the VDSO to its checkpointed location.
- Restore the MIPS32 cBPF JIT, after having reverted the enablement
of the eBPF JIT for MIPS32 systems in the 5.5 cycle.
- Improve cop0 counter synchronization behaviour whilst onlining CPUs
by running with interrupts disabled.
- Better match FPU behaviour when emulating multiply-accumulate
instructions on pre-r6 systems that implement IEEE754-2008 style
MACs.
- Loongson64 kernels now build using the MIPS64r2 ISA, allowing them
to take advantage of instructions introduced by r2.
- Support for the Ingenic X1000 SoC & the really nice little CU Neo
development board that's using it.
- Support for WMAC on GARDENA Smart Gateway devices.
- Lots of cleanup & refactoring of SGI IP27 (Origin 2*) support in
preparation for introducing IP35 (Origin 3*) support.
- Various Kconfig & Makefile cleanups"
* tag 'mips_5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (60 commits)
MIPS: PCI: Add detection of IOC3 on IO7, IO8, IO9 and Fuel
MIPS: Loongson64: Disable exec hazard
MIPS: Loongson64: Bump ISA level to MIPSR2
MIPS: Make DIEI support as a config option
MIPS: OCTEON: octeon-irq: fix spelling mistake "to" -> "too"
MIPS: asm: local: add barriers for Loongson
MIPS: Loongson64: Select mac2008 only feature
MIPS: Add MAC2008 Support
Revert "MIPS: Add custom serial.h with BASE_BAUD override for generic kernel"
MIPS: sort MIPS and MIPS_GENERIC Kconfig selects alphabetically (again)
MIPS: make CPU_HAS_LOAD_STORE_LR opt-out
MIPS: generic: don't unconditionally select PINCTRL
MIPS: don't explicitly select LIBFDT in Kconfig
MIPS: sync-r4k: do slave counter synchronization with disabled HW interrupts
MIPS: SGI-IP30: Check for valid pointer before using it
MIPS: syscalls: fix indentation of the 'SYSNR' message
MIPS: boot: fix typo in 'vmlinux.lzma.its' target
MIPS: fix indentation of the 'RELOCS' message
dt-bindings: Document loongson vendor-prefix
MIPS: CU1000-Neo: Refresh defconfig to support HWMON and WiFi.
...
This tag contains a handful of patches that I'd like to target for this merge
window:
* Support for kasan.
* 32-bit physical addresses on rv32i-based systems.
* Support for CONFIG_DEBUG_VIRTUAL
* DT entry for the FU540 GPIO controller, which has recently had a device
driver merged.
These boot a buildroot-based system on QEMU's virt board for me.
-----BEGIN PGP SIGNATURE-----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=W7f7
-----END PGP SIGNATURE-----
Merge tag 'riscv-for-linus-5.6-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt:
"This contains a handful of patches for this merge window:
- Support for kasan
- 32-bit physical addresses on rv32i-based systems
- Support for CONFIG_DEBUG_VIRTUAL
- DT entry for the FU540 GPIO controller, which has recently had a
device driver merged
These boot a buildroot-based system on QEMU's virt board for me"
* tag 'riscv-for-linus-5.6-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: dts: Add DT support for SiFive FU540 GPIO driver
riscv: mm: add support for CONFIG_DEBUG_VIRTUAL
riscv: keep 32-bit kernel to 32-bit phys_addr_t
kasan: Add riscv to KASAN documentation.
riscv: Add KASAN support
kasan: No KASAN's memmove check if archs don't have it.
Pull x86 fixes from Ingo Molnar:
"Misc fixes:
- three fixes and a cleanup for the resctrl code
- a HyperV fix
- a fix to /proc/kcore contents in live debugging sessions
- a fix for the x86 decoder opcode map"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/decoder: Add TEST opcode to Group3-2
x86/resctrl: Clean up unused function parameter in mkdir path
x86/resctrl: Fix a deadlock due to inaccurate reference
x86/resctrl: Fix use-after-free due to inaccurate refcount of rdtgroup
x86/resctrl: Fix use-after-free when deleting resource groups
x86/hyper-v: Add "polling" bit to hv_synic_sint
x86/crash: Define arch_crash_save_vmcoreinfo() if CONFIG_CRASH_CORE=y
Don't instrument 3 more files that contain debugging facilities and
produce large amounts of uninteresting coverage for every syscall.
The following snippets are sprinkled all over the place in kcov traces
in a debugging kernel. We already try to disable instrumentation of
stack unwinding code and of most debug facilities. I guess we did not
use fault-inject.c at the time, and stacktrace.c was somehow missed (or
something has changed in kernel/configs). This change both speeds up
kcov (kernel doesn't need to store these PCs, user-space doesn't need to
process them) and frees trace buffer capacity for more useful coverage.
should_fail
lib/fault-inject.c:149
fail_dump
lib/fault-inject.c:45
stack_trace_save
kernel/stacktrace.c:124
stack_trace_consume_entry
kernel/stacktrace.c:86
stack_trace_consume_entry
kernel/stacktrace.c:89
... a hundred frames skipped ...
stack_trace_consume_entry
kernel/stacktrace.c:93
stack_trace_consume_entry
kernel/stacktrace.c:86
Link: http://lkml.kernel.org/r/20200116111449.217744-1-dvyukov@gmail.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use PHYS_PFN() macro in io_mapping_map_atomic_wc() instead of open coded
variant.
Link: http://lkml.kernel.org/r/20191209165624.56351-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There were few episodes of silent downgrade to an executable stack over
years:
1) linking innocent looking assembly file will silently add executable
stack if proper linker options is not given as well:
$ cat f.S
.intel_syntax noprefix
.text
.globl f
f:
ret
$ cat main.c
void f(void);
int main(void)
{
f();
return 0;
}
$ gcc main.c f.S
$ readelf -l ./a.out
GNU_STACK 0x0000000000000000 0x0000000000000000 0x0000000000000000
0x0000000000000000 0x0000000000000000 RWE 0x10
^^^
2) converting C99 nested function into a closure
https://nullprogram.com/blog/2019/11/15/
void intsort2(int *base, size_t nmemb, _Bool invert)
{
int cmp(const void *a, const void *b)
{
int r = *(int *)a - *(int *)b;
return invert ? -r : r;
}
qsort(base, nmemb, sizeof(*base), cmp);
}
will silently require stack trampolines while non-closure version will
not.
Without doubt this behaviour is documented somewhere, add a warning so
that developers and users can at least notice. After so many years of
x86_64 having proper executable stack support it should not cause too
many problems.
Link: http://lkml.kernel.org/r/20191208171918.GC19716@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Will Deacon <will@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The variable inode may be NULL in reiserfs_insert_item(), but there is
no check before accessing the member of inode.
Fix this by adding NULL pointer check before calling reiserfs_debug().
Link: http://lkml.kernel.org/r/79c5135d-ff25-1cc9-4e99-9f572b88cc00@huawei.com
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Cc: zhengbin <zhengbin13@huawei.com>
Cc: Hu Shiyuan <hushiyuan@huawei.com>
Cc: Feilong Lin <linfeilong@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This message leads to thinking that memory protection is not implemented
for the said architecture, whereas absence of CONFIG_STRICT_KERNEL_RWX
only means that memory protection has not been selected at compile time.
Don't print this message when CONFIG_ARCH_HAS_STRICT_KERNEL_RWX is
selected by the architecture. Instead, print "Kernel memory protection
not selected by kernel config."
Link: http://lkml.kernel.org/r/62477e446d9685459d4f27d193af6ff1bd69d55f.1578557581.git.christophe.leroy@c-s.fr
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "init/main.c: minor cleanup/bugfix of envvar handling", v2.
unknown_bootoption passes unrecognized command line arguments to init as
either environment variables or arguments. Some of the logic in the
function is broken for quoted command line arguments.
When an argument of the form param="value" is processed by parse_args
and passed to unknown_bootoption, the command line has
param\0"value\0
with val pointing to the beginning of value. The helper function
repair_env_string is then used to restore the '=' character that was
removed by parse_args, and strip the quotes off fully. This results in
param=value\0\0
and val ends up pointing to the 'a' instead of the 'v' in value. This
bug was introduced when repair_env_string was refactored into a separate
function, and the decrement of val in repair_env_string became dead
code.
This causes two problems in unknown_bootoption in the two places where
the val pointer is used as a substitute for the length of param:
1. An argument of the form param=".value" is misinterpreted as a
potential module parameter, with the result that it will not be
placed in init's environment.
2. An argument of the form param="value" is checked to see if param is
an existing environment variable that should be overwritten, but the
comparison is off-by-one and compares 'param=v' instead of 'param='
against the existing environment. So passing, for example,
TERM="vt100" on the command line results in init being passed both
TERM=linux and TERM=vt100 in its environment.
Patch 1 adds logging for the arguments and environment passed to init
and is independent of the rest: it can be dropped if this is
unnecessarily verbose.
Patch 2 removes repair_env_string from initcall parameter parsing in
do_initcall_level, as that uses a separate copy of the command line now
and the repairing is no longer necessary.
Patch 3 fixes the bug in unknown_bootoption by recording the length of
param explicitly instead of implying it from val-param.
This patch (of 3):
Commit a99cd11251 ("init: fix bug where environment vars can't be
passed via boot args") introduced two minor bugs in unknown_bootoption
by factoring out the quoted value handling into a separate function.
When value is quoted, repair_env_string will move the value up 1 byte to
strip the quotes, so val in unknown_bootoption no longer points to the
actual location of the value.
The result is that an argument of the form param=".value" is mistakenly
treated as a potential module parameter and is not placed in init's
environment, and an argument of the form param="value" can result in a
duplicate environment variable: eg TERM="vt100" on the command line will
result in both TERM=linux and TERM=vt100 being placed into init's
environment.
Fix this by recording the length of the param before calling
repair_env_string instead of relying on val.
Link: http://lkml.kernel.org/r/20191212180023.24339-4-nivedita@alum.mit.edu
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Krzysztof Mazur <krzysiek@podlesie.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
