Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

[pull] master from torvalds:master #40

Merged
merged 119 commits into from
Jun 6, 2020
Merged

[pull] master from torvalds:master #40

merged 119 commits into from
Jun 6, 2020

Conversation

pull[bot]
Copy link

@pull pull bot commented Jun 6, 2020

See Commits and Changes for more details.


Created by pull[bot]. Want to support this open source service? Please star it : )

kaixuxiakx and others added 30 commits May 7, 2020 11:00
The DIOREAD_NOLOCK flag has been cleared when doing the test_opt
that is meaningless, so remove the unnecessary test_opt for DIOREAD_NOLOCK.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Link: https://lore.kernel.org/r/1586751862-19437-1-git-send-email-kaixuxia@tencent.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] KSPP#21
[3] commit 7649773 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David Teigland <teigland@redhat.com>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] KSPP#21
[3] commit 7649773 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Fix the following coccicheck warning:
fs/dlm/rcom.c:566:2-3: Unneeded semicolon

Signed-off-by: Wu Bo <wubo40@huawei.com>
Signed-off-by: David Teigland <teigland@redhat.com>
We saw an issue in a production server on a customer deployment where
DLM 4.0.7 gets "stuck" and unable to join new lockspaces.

There is no useful response for the dlm in do_event() if
wait_event_interruptible() is interrupted, so switch to
wait_event().

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Building a kernel with clang sometimes fails with an objtool error in dlm:

fs/dlm/lock.o: warning: objtool: revert_lock_pc()+0xbd: can't find jump dest instruction at .text+0xd7fc

The problem is that BUG() never returns and the compiler knows
that anything after it is unreachable, however the panic still
emits some code that does not get fully eliminated.

Having both BUG() and panic() is really pointless as the BUG()
kills the current process and the subsequent panic() never hits.
In most cases, we probably don't really want either and should
replace the DLM_ASSERT() statements with WARN_ON(), as has
been done for some of them.

Remove the BUG() here so the user at least sees the panic message
and we can reliably build randconfig kernels.

Fixes: e7fd417 ("[DLM] The core of the DLM for GFS2/CLVM")
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: clang-built-linux@googlegroups.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Teigland <teigland@redhat.com>
We can use the ext4_has_feature_bigalloc() function directly to check
bigalloc feature and the variable has_bigalloc is reduncant, so remove
it.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/1586935542-29588-1-git-send-email-kaixuxia@tencent.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The variable ret is being initialized with a value that is
never read and it is being updated later with a new value. The
initialization is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
This code was using get_user_pages*(), in a "Case 1" scenario
(Direct IO), using the categorization from [1]. That means that it's
time to convert the get_user_pages*() + put_page() calls to
pin_user_pages*() + unpin_user_pages() calls.

There is some helpful background in [2]: basically, this is a small
part of fixing a long-standing disconnect between pinning pages, and
file systems' use of those pages.

[1] Documentation/core-api/pin_user_pages.rst

[2] "Explicit pinning of user-space pages":
    https://lwn.net/Articles/807108/

Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Martin Brandenburg <martin@omnibond.com>
Cc: devel@lists.orangefs.org
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Make the inode hash table RCU searchable so that searches that want to
access or modify an inode without taking a ref on that inode can do so
without taking the inode hash table lock.

The main thing this requires is some RCU annotation on the list
manipulation operations.  Inodes are already freed by RCU in most cases.

Users of this interface must take care as the inode may be still under
construction or may be being torn down around them.

There are at least three instances where this can be of use:

 (1) Testing whether the inode number iunique() is going to return is
     currently unique (the iunique_lock is still held).

 (2) Ext4 date stamp updating.

 (3) AFS callback breaking.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
cc: linux-ext4@vger.kernel.org
cc: linux-afs@lists.infradead.org
Map the EACCES error that is produced by some ICMP6 packets to EHOSTUNREACH
when we get them as EACCES has other meanings within a filesystem context.

Signed-off-by: David Howells <dhowells@redhat.com>
…r_ID

The user ID value isn't actually much use - and leaks a kernel pointer or a
userspace value - so replace it with the call debug ID, which appears in trace
points.

Signed-off-by: David Howells <dhowells@redhat.com>
When a lookup is done in an AFS directory, the filesystem will speculate
and fetch up to 49 other statuses for files in the same directory and fetch
those as well, turning them into inodes or updating inodes that already
exist.

However, occasionally, a callback break might go missing due to NAT timing
out, but the afs filesystem doesn't then realise that the directory is not
up to date.

Alleviate this by using one of the status slots to check the directory in
which the lookup is being done.

Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Suggested-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
The U-version VLDB volume record retrieved by the VL.GetEntryByNameU rpc op
carries a change counter (the serverUnique field) for each fileserver
listed in the record as backing that volume.  This is incremented whenever
the registration details for a fileserver change (such as its address
list).  Note that the same value will be seen in all UVLDB records that
refer to that fileserver.

This should be checked before calling the VL server to re-query the address
list for a fileserver.  If it's the same, there's no point doing the query.

Reported-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Split the usage count on the afs_server struct to have an active count that
registers who's actually using it separately from the reference count on
the object.

This allows a future patch to dispatch polling probes without advancing the
"unuse" time into the future each time we emit a probe, which would
otherwise prevent unused server records from expiring.

Included in this:

 (1) The latter part of afs_destroy_server() in which the RCU destruction
     of afs_server objects is invoked and the outstanding server count is
     decremented is split out into __afs_put_server().

 (2) afs_put_server() now calls __afs_put_server() rather then setting the
     management timer.

 (3) The calls begun by afs_fs_give_up_all_callbacks() and
     afs_fs_get_capabilities() can now take a ref on the server record, so
     afs_destroy_server() can just drop its ref and needn't wait for the
     completion of these calls.  They'll put the ref when they're done.

 (4) Because of (3), afs_fs_probe_done() no longer needs to wake up
     afs_destroy_server() with server->probe_outstanding.

 (5) afs_gc_servers can be simplified.  It only needs to check if
     server->active is 0 rather than playing games with the refcount.

 (6) afs_manage_servers() can propose a server for gc if usage == 0 rather
     than if ref == 1.  The gc is effected by (5).

Signed-off-by: David Howells <dhowells@redhat.com>
When an AFS client accesses a file, it receives a limited-duration callback
promise that the server will notify it if another client changes a file.
This callback duration can be a few hours in length.

If a client mounts a volume and then an application prevents it from being
unmounted, say by chdir'ing into it, but then does nothing for some time,
the rxrpc_peer record will expire and rxrpc-level keepalive will cease.

If there is NAT or a firewall between the client and the server, the route
back for the server may close after a comparatively short duration, meaning
that attempts by the server to notify the client may then bounce.

The client, however, may (so far as it knows) still have a valid unexpired
promise and will then rely on its cached data and will not see changes made
on the server by a third party until it incidentally rechecks the status or
the promise needs renewal.

To deal with this, the client needs to regularly probe the server.  This
has two effects: firstly, it keeps a route open back for the server, and
secondly, it causes the server to disgorge any notifications that got
queued up because they couldn't be sent.

Fix this by adding a mechanism to emit regular probes.

Two levels of probing are made available: Under normal circumstances the
'slow' queue will be used for a fileserver - this just probes the preferred
address once every 5 mins or so; however, if server fails to respond to any
probes, the server will shift to the 'fast' queue from which all its
interfaces will be probed every 30s.  When it finally responds, the record
will switch back to the slow queue.

Further notes:

 (1) Probing is now no longer driven from the fileserver rotation
     algorithm.

 (2) Probes are dispatched to all interfaces on a fileserver when that an
     afs_server object is set up to record it.

 (3) The afs_server object is removed from the probe queues when we start
     to probe it.  afs_is_probing_server() returns true if it's not listed
     - ie. it's undergoing probing.

 (4) The afs_server object is added back on to the probe queue when the
     final outstanding probe completes, but the probed_at time is set when
     we're about to launch a probe so that it's not dependent on the probe
     duration.

 (5) The timer and the work item added for this must be handed a count on
     net->servers_outstanding, which they hand on or release.  This makes
     sure that network namespace cleanup waits for them.

Fixes: d2ddc77 ("afs: Overhaul volume and server record caching and fileserver rotation")
Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Show more information in /proc/net/afs/servers to make it easier to see
what's going on with the server probing.

Signed-off-by: David Howells <dhowells@redhat.com>
afs_vol_interest objects represent the volume IDs currently being accessed
from a fileserver.  These hold lists of afs_cb_interest objects that
repesent the superblocks using that volume ID on that server.

When a callback notification from the server telling of a modification by
another client arrives, the volume ID specified in the notification is
looked up in the server's afs_vol_interest list.  Through the
afs_cb_interest list, the relevant superblocks can be iterated over and the
specific inode looked up and marked in each one.

Make the following efficiency improvements:

 (1) Hold rcu_read_lock() over the entire processing rather than locking it
     each time.

 (2) Do all the callbacks for each vid together rather than individually.
     Each volume then only needs to be looked up once.

 (3) afs_vol_interest objects are now stored in an rb_tree rather than a
     flat list to reduce the lookup step count.

 (4) afs_vol_interest lookup is now done with RCU, but because it's in an
     rb_tree which may rotate under us, a seqlock is used so that if it
     changes during the walk, we repeat the walk with a lock held.

With this and the preceding patch which adds RCU-based lookups in the inode
cache, target volumes/vnodes can be taken without the need to take any
locks, except on the target itself.

Signed-off-by: David Howells <dhowells@redhat.com>
Set a flag in the call struct to indicate an unmarshalling error rather
than return and handle an error from the decoding of file statuses.  This
flag is checked on a successful return from the delivery function.

Signed-off-by: David Howells <dhowells@redhat.com>
Remove the error argument from afs_protocol_error() as it's always
-EBADMSG.

Signed-off-by: David Howells <dhowells@redhat.com>
As a prelude to implementing asynchronous fileserver operations in the afs
filesystem, rename struct afs_fs_cursor to afs_operation.

This struct is going to form the core of the operation management and is
going to acquire more members in later.

Signed-off-by: David Howells <dhowells@redhat.com>
The "nolease" mount option is only supported for SMB2+ mounts.
Fail with appropriate error message if vers=1.0 option is passed.

Signed-off-by: Kenneth D'souza <kdsouza@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The variable rc is being initialized with a value that is never read
and it is being updated later with a new value.  The initialization is
redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
If we mount a very specific DFS link

    \\FS0.FOO.COM\dfs\link -> \FS0\share1, \FS1\share2

where its target list contains NB names ("FS0" & "FS1") rather than
FQDN ones ("FS0.FOO.COM" & "FS1.FOO.COM"), we end up connecting to
\FOO\share1 but server->hostname will have "FOO.COM".  The reason is
because both "FS0" and "FS0.FOO.COM" resolve to same IP address and
they share same TCP server connection, but "FS0.FOO.COM" was the first
hostname set -- which is OK.

However, if the echo thread timeouts and we still have a good
connection to "FS0", in cifs_reconnect()

    rc = generic_ip_connect(server) -> success
    if (rc) {
            ...
            reconn_inval_dfs_target(server, cifs_sb, &tgt_list,
	                            &tgt_it);
            ...
     }
     ...

it successfully reconnects to "FS0" server but does not set up next
DFS target - which should be the same target server "\FS0\share1" -
and server->hostname remains set to "FS0.FOO.COM" rather than "FS0",
as reconn_inval_dfs_target() would have it set to "FS0" if called
earlier.

Finally, in __smb2_reconnect(), the reconnect of tcons would fail
because tcon->ses->server->hostname (FS0.FOO.COM) does not match DFS
target's hostname (FS0).

Fix that by calling reconn_inval_dfs_target() before
generic_ip_connect() so server->hostname will get updated correctly
prior to reconnecting its tcons in __smb2_reconnect().

With "cifs: handle hostnames that resolve to same ip in failover"
patch

    - The above problem would not occur.
    - We could save an DNS query to find out that they both resolve to
      the same ip address.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In order to support reconnect to hostnames that resolve to same ip
address, besides relying on the currently set hostname to match DFS
targets, attempt to resolve the targets and then match their addresses
with the reconnected server ip address.

For instance, if we have two hostnames "FOO" and "BAR", and both
resolve to the same ip address, we would be able to handle failover in
DFS paths like

    \\FOO\dfs\link1 -> [ \BAZ\share2 (*), \BAR\share1 ]
    \\FOO\dfs\link2 -> [ \BAZ\share2 (*), \FOO\share1 ]

so when "BAZ" is no longer accessible, link1 and link2 would get
reconnected despite having different target hostnames.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The target iterator parameter "it" is not used in
reconn_setup_dfs_targets(), so just remove it.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Move a lot of structures and arrays off the stack and into a dynamically
allocated structure instead.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Move some large data structures off the stack and into dynamically
allocated memory in the function smb2_ioctl_query_info

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In order to handle workloads where it is important to make sure that
a buggy app did not delete content on the drive, the new mount option
"nodelete" allows standard permission checks on the server to work,
but prevents on the client any attempts to unlink a file or delete
a directory on that mount point.  This can be helpful when running
a little understood app on a network mount that contains important
content that should not be deleted.

Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Use pr_fmt to standardize all logging for fs/cifs.

Some logging output had no CIFS: specific prefix.

Now all output has one of three prefixes:

o CIFS:
o CIFS: VFS:
o Root-CIFS:

Miscellanea:

o Convert printks to pr_<level>
o Neaten macro definitions
o Remove embedded CIFS: prefixes from formats
o Convert "illegal" to "invalid"
o Coalesce formats
o Add missing '\n' format terminations
o Consolidate multiple cifs_dbg continuations into single calls
o More consistent use of upper case first word output logging
o Multiline statement argument alignment and wrapping

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
dhowells and others added 19 commits June 4, 2020 15:37
Add a tracepoint to track the lifetime of the afs_volume struct.

Signed-off-by: David Howells <dhowells@redhat.com>
Reorganise afs_volume objects such that they're in a tree keyed on volume
ID, rooted at on an afs_cell object rather than being in multiple trees,
each of which is rooted on an afs_server object.

afs_server structs become per-cell and acquire a pointer to the cell.

The process of breaking a callback then starts with finding the server by
its network address, following that to the cell and then looking up each
volume ID in the volume tree.

This is simpler than the afs_vol_interest/afs_cb_interest N:M mapping web
and allows those structs and the code for maintaining them to be simplified
or removed.

It does make a couple of things a bit more tricky, though:

 (1) Operations now start with a volume, not a server, so there can be more
     than one answer as to whether or not the server we'll end up using
     supports the FS.InlineBulkStatus RPC.

 (2) CB RPC operations that specify the server UUID.  There's still a tree
     of servers by UUID on the afs_net struct, but the UUIDs in it aren't
     guaranteed unique.

Signed-off-by: David Howells <dhowells@redhat.com>
Whilst it shouldn't happen, it is possible for multiple fileservers to
share a UUID, particularly if an entire cell has been duplicated, UUIDs and
all.  In such a case, it's not necessarily possible to map the effect of
the CB.InitCallBackState3 incoming RPC to a specific server unambiguously
by UUID and thus to a specific cell.

Indeed, there's a problem whereby multiple server records may need to
occupy the same spot in the rb_tree rooted in the afs_net struct.

Fix this by allowing servers to form a list, with the head of the list in
the tree.  When the front entry in the list is removed, the second in the
list just replaces it.  afs_init_callback_state() then just goes down the
line, poking each server in the list.

This means that some servers will be unnecessarily poked, unfortunately.
An alternative would be to route by call parameters.

Reported-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Fixes: d2ddc77 ("afs: Overhaul volume and server record caching and fileserver rotation")
Fix afs_statfs() so that the value for f_bavail and f_bfree don't go
"negative" if the number of blocks in use by a volume exceeds the max quota
for that volume.

Signed-off-by: David Howells <dhowells@redhat.com>
Don't use the running state for fileserver probes to make decisions about
which server to use as the state is cleared at the start of a probe and
also intermediate values might be misleading.

Instead, add a separate 'latest known' rtt in the afs_server struct and a
flag to indicate if the server is known to be responding and update these
as and when we know what to change them to.

Signed-off-by: David Howells <dhowells@redhat.com>
Display more information about the state of a server record, including the
flags, rtt and break counter plus the probe state for each server in
/proc/net/afs/servers.

Rearrange the server flags a bit to make them easier to read at a glance in
the proc file.

Signed-off-by: David Howells <dhowells@redhat.com>
…uickly

Adjust the fileserver rotation algorithm so that if we've tried all the
addresses on a server (cumulatively over multiple operations) until we've
run out of untried addresses, immediately reprobe all that server's
interfaces and retry the op at least once before we move onto the next
server.

Signed-off-by: David Howells <dhowells@redhat.com>
Currently the end user is unaware with what sec type the
cifs share is mounted if no sec=<type> option is parsed.
With this patch one can easily check from DebugData.

Example:
1) Name: x.x.x.x Uses: 1 Capability: 0x8001f3fc	Session Status: 1 Security type: RawNTLMSSP

Signed-off-by: Kenneth D'souza <kdsouza@redhat.com>
Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Aurelien Aptel <aaptel@suse.com>
SMB2_read/SMB2_write check and use cifs_io_parms->server, which might
be uninitialized memory.

This change makes all callers zero-initialize the struct.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Move the channel (TCP_Server_Info*) selection from the tranport
layer to higher in the call stack so that:

- credit handling is done with the server that will actually be used
  to send.
  * ->wait_mtu_credit
  * ->set_credits / set_credits
  * ->add_credits / add_credits
  * add_credits_and_wake_if

- potential reconnection (smb2_reconnect) done when initializing a
  request is checked and done with the server that will actually be
  used to send.

To do this:

- remove the cifs_pick_channel() call out of compound_send_recv()

- select channel and pass it down by adding a cifs_pick_channel(ses)
  call in:
  - smb311_posix_mkdir
  - SMB2_open
  - SMB2_ioctl
  - __SMB2_close
  - query_info
  - SMB2_change_notify
  - SMB2_flush
  - smb2_async_readv  (if none provided in context param)
  - SMB2_read         (if none provided in context param)
  - smb2_async_writev (if none provided in context param)
  - SMB2_write        (if none provided in context param)
  - SMB2_query_directory
  - send_set_info
  - SMB2_oplock_break
  - SMB311_posix_qfs_info
  - SMB2_QFS_info
  - SMB2_QFS_attr
  - smb2_lockv
  - SMB2_lease_break
    - smb2_compound_op
  - smb2_set_ea
  - smb2_ioctl_query_info
  - smb2_query_dir_first
  - smb2_query_info_comound
  - smb2_query_symlink
  - cifs_writepages
  - cifs_write_from_iter
  - cifs_send_async_read
  - cifs_read
  - cifs_readpages

- add TCP_Server_Info *server param argument to:
  - cifs_send_recv
  - compound_send_recv
  - SMB2_open_init
  - SMB2_query_info_init
  - SMB2_set_info_init
  - SMB2_close_init
  - SMB2_ioctl_init
  - smb2_iotcl_req_init
  - SMB2_query_directory_init
  - SMB2_notify_init
  - SMB2_flush_init
  - build_qfs_info_req
  - smb2_hdr_assemble
  - smb2_reconnect
  - fill_small_buf
  - smb2_plain_req_init
  - __smb2_plain_req_init

The read/write codepath is different than the rest as it is using
pages, io iterators and async calls. To deal with those we add a
server pointer in the cifs_writedata/cifs_readdata/cifs_io_parms
context struct and set it in:

- cifs_writepages      (wdata)
- cifs_write_from_iter (wdata)
- cifs_readpages       (rdata)
- cifs_send_async_read (rdata)

The [rw]data->server pointer is eventually copied to
cifs_io_parms->server to pass it down to SMB2_read/SMB2_write.
If SMB2_read/SMB2_write is called from a different place that doesn't
set the server field it will pick a channel.

Some places do not pick a channel and just use ses->server or
cifs_ses_server(ses). All cifs_ses_server(ses) calls are in codepaths
involving negprot/sess.setup.

- SMB2_negotiate         (binding channel)
- SMB2_sess_alloc_buffer (binding channel)
- SMB2_echo              (uses provided one)
- SMB2_logoff            (uses master)
- SMB2_tdis              (uses master)

(list not exhaustive)

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Remove static checker warning pointed out by Dan Carpenter:

The patch feeaec6: "cifs: multichannel: move channel selection
above transport layer" from Apr 24, 2020, leads to the following
static checker warning:

        fs/cifs/smb2pdu.c:149 smb2_hdr_assemble()
        error: we previously assumed 'tcon->ses' could be null (see line 133)

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
CC: Aurelien Aptel <aptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add a cifs_chan pointer in struct cifs_ses that points to the channel
currently being bound if ses->binding is true.

Previously it was always the channel past the established count.

This will make reconnecting (and rebinding) a channel easier later on.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
first steps in trying to make channels properly reconnect.

* add cifs_ses_find_chan() function to find the enclosing cifs_chan
  struct it belongs to
* while we have the session lock and are redoing negprot and
  sess.setup in smb2_reconnect() redo the binding of channels.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
    To 2.27

Signed-off-by: Steve French <stfrench@microsoft.com>
…el/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "A lot of bug fixes and cleanups for ext4, including:

   - Fix performance problems found in dioread_nolock now that it is the
     default, caused by transaction leaks.

   - Clean up fiemap handling in ext4

   - Clean up and refactor multiple block allocator (mballoc) code

   - Fix a problem with mballoc with a smaller file systems running out
     of blocks because they couldn't properly use blocks that had been
     reserved by inode preallocation.

   - Fixed a race in ext4_sync_parent() versus rename()

   - Simplify the error handling in the extent manipulation code

   - Make sure all metadata I/O errors are felected to
     ext4_ext_dirty()'s and ext4_make_inode_dirty()'s callers.

   - Avoid passing an error pointer to brelse in ext4_xattr_set()

   - Fix race which could result to freeing an inode on the dirty last
     in data=journal mode.

   - Fix refcount handling if ext4_iget() fails

   - Fix a crash in generic/019 caused by a corrupted extent node"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (58 commits)
  ext4: avoid unnecessary transaction starts during writeback
  ext4: don't block for O_DIRECT if IOCB_NOWAIT is set
  ext4: remove the access_ok() check in ext4_ioctl_get_es_cache
  fs: remove the access_ok() check in ioctl_fiemap
  fs: handle FIEMAP_FLAG_SYNC in fiemap_prep
  fs: move fiemap range validation into the file systems instances
  iomap: fix the iomap_fiemap prototype
  fs: move the fiemap definitions out of fs.h
  fs: mark __generic_block_fiemap static
  ext4: remove the call to fiemap_check_flags in ext4_fiemap
  ext4: split _ext4_fiemap
  ext4: fix fiemap size checks for bitmap files
  ext4: fix EXT4_MAX_LOGICAL_BLOCK macro
  add comment for ext4_dir_entry_2 file_type member
  jbd2: avoid leaking transaction credits when unreserving handle
  ext4: drop ext4_journal_free_reserved()
  ext4: mballoc: use lock for checking free blocks while retrying
  ext4: mballoc: refactor ext4_mb_good_group()
  ext4: mballoc: introduce pcpu seqcnt for freeing PA to improve ENOSPC handling
  ext4: mballoc: refactor ext4_mb_discard_preallocations()
  ...
…ernel/git/dhowells/linux-fs

Pull AFS updates from David Howells:
 "There's some core VFS changes which affect a couple of filesystems:

   - Make the inode hash table RCU safe and providing some RCU-safe
     accessor functions. The search can then be done without taking the
     inode_hash_lock. Care must be taken because the object may be being
     deleted and no wait is made.

   - Allow iunique() to avoid taking the inode_hash_lock.

   - Allow AFS's callback processing to avoid taking the inode_hash_lock
     when using the inode table to find an inode to notify.

   - Improve Ext4's time updating. Konstantin Khlebnikov said "For now,
     I've plugged this issue with try-lock in ext4 lazy time update.
     This solution is much better."

  Then there's a set of changes to make a number of improvements to the
  AFS driver:

   - Improve callback (ie. third party change notification) processing
     by:

      (a) Relying more on the fact we're doing this under RCU and by
          using fewer locks. This makes use of the RCU-based inode
          searching outlined above.

      (b) Moving to keeping volumes in a tree indexed by volume ID
          rather than a flat list.

      (c) Making the server and volume records logically part of the
          cell. This means that a server record now points directly at
          the cell and the tree of volumes is there. This removes an N:M
          mapping table, simplifying things.

   - Improve keeping NAT or firewall channels open for the server
     callbacks to reach the client by actively polling the fileserver on
     a timed basis, instead of only doing it when we have an operation
     to process.

   - Improving detection of delayed or lost callbacks by including the
     parent directory in the list of file IDs to be queried when doing a
     bulk status fetch from lookup. We can then check to see if our copy
     of the directory has changed under us without us getting notified.

   - Determine aliasing of cells (such as a cell that is pointed to be a
     DNS alias). This allows us to avoid having ambiguity due to
     apparently different cells using the same volume and file servers.

   - Improve the fileserver rotation to do more probing when it detects
     that all of the addresses to a server are listed as non-responsive.
     It's possible that an address that previously stopped responding
     has become responsive again.

  Beyond that, lay some foundations for making some calls asynchronous:

   - Turn the fileserver cursor struct into a general operation struct
     and hang the parameters off of that rather than keeping them in
     local variables and hang results off of that rather than the call
     struct.

   - Implement some general operation handling code and simplify the
     callers of operations that affect a volume or a volume component
     (such as a file). Most of the operation is now done by core code.

   - Operations are supplied with a table of operations to issue
     different variants of RPCs and to manage the completion, where all
     the required data is held in the operation object, thereby allowing
     these to be called from a workqueue.

   - Put the standard "if (begin), while(select), call op, end" sequence
     into a canned function that just emulates the current behaviour for
     now.

  There are also some fixes interspersed:

   - Don't let the EACCES from ICMP6 mapping reach the user as such,
     since it's confusing as to whether it's a filesystem error. Convert
     it to EHOSTUNREACH.

   - Don't use the epoch value acquired through probing a server. If we
     have two servers with the same UUID but in different cells, it's
     hard to draw conclusions from them having different epoch values.

   - Don't interpret the argument to the CB.ProbeUuid RPC as a
     fileserver UUID and look up a fileserver from it.

   - Deal with servers in different cells having the same UUIDs. In the
     event that a CB.InitCallBackState3 RPC is received, we have to
     break the callback promises for every server record matching that
     UUID.

   - Don't let afs_statfs return values that go below 0.

   - Don't use running fileserver probe state to make server selection
     and address selection decisions on. Only make decisions on final
     state as the running state is cleared at the start of probing"

Acked-by: Al Viro <viro@zeniv.linux.org.uk> (fs/inode.c part)

* tag 'afs-next-20200604' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (27 commits)
  afs: Adjust the fileserver rotation algorithm to reprobe/retry more quickly
  afs: Show more a bit more server state in /proc/net/afs/servers
  afs: Don't use probe running state to make decisions outside probe code
  afs: Fix afs_statfs() to not let the values go below zero
  afs: Fix the by-UUID server tree to allow servers with the same UUID
  afs: Reorganise volume and server trees to be rooted on the cell
  afs: Add a tracepoint to track the lifetime of the afs_volume struct
  afs: Detect cell aliases 3 - YFS Cells with a canonical cell name op
  afs: Detect cell aliases 2 - Cells with no root volumes
  afs: Detect cell aliases 1 - Cells with root volumes
  afs: Implement client support for the YFSVL.GetCellName RPC op
  afs: Retain more of the VLDB record for alias detection
  afs: Fix handling of CB.ProbeUuid cache manager op
  afs: Don't get epoch from a server because it may be ambiguous
  afs: Build an abstraction around an "operation" concept
  afs: Rename struct afs_fs_cursor to afs_operation
  afs: Remove the error argument from afs_protocol_error()
  afs: Set error flag rather than return error from file status decode
  afs: Make callback processing more efficient.
  afs: Show more information in /proc/net/afs/servers
  ...
…ifs-2.6

Pull cifs updates from Steve French:
 "22 changesets, 2 for stable.

  Includes big performance improvement for large i/o when using
  multichannel, also includes DFS fixes"

* tag '5.8-rc-smb3-fixes-part-1' of git://git.samba.org/sfrench/cifs-2.6: (22 commits)
  cifs: update internal module version number
  cifs: multichannel: try to rebind when reconnecting a channel
  cifs: multichannel: use pointer for binding channel
  smb3: remove static checker warning
  cifs: multichannel: move channel selection above transport layer
  cifs: multichannel: always zero struct cifs_io_parms
  cifs: dump Security Type info in DebugData
  smb3: fix incorrect number of credits when ioctl MaxOutputResponse > 64K
  smb3: default to minimum of two channels when multichannel specified
  cifs: multichannel: move channel selection in function
  cifs: fix minor typos in comments and log messages
  smb3: minor update to compression header definitions
  cifs: minor fix to two debug messages
  cifs: Standardize logging output
  smb3: Add new parm "nodelete"
  cifs: move some variables off the stack in smb2_ioctl_query_info
  cifs: reduce stack use in smb2_compound_op
  cifs: get rid of unused parameter in reconn_setup_dfs_targets()
  cifs: handle hostnames that resolve to same ip in failover
  cifs: set up next DFS target before generic_ip_connect()
  ...
…teigland/linux-dlm

Pull dlm updates from David Teigland:
 "This set includes a couple minor cleanups, and dropping the
  interruptible from a wait_event that waits for an event from the
  userspace cluster management"

* tag 'dlm-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
  dlm: remove BUG() before panic()
  dlm: Switch to using wait_event()
  fs:dlm:remove unneeded semicolon in rcom.c
  dlm: user: Replace zero-length array with flexible-array member
  dlm: dlm_internal: Replace zero-length array with flexible-array member
…kernel/git/hubcap/linux

Pull orangefs updates from Mike Marshall:

 - John Hubbard's conversion from get_user_pages() to pin_user_pages()

 - Colin Ian King's removal of an unneeded variable initialization

* tag 'for-linus-5.8-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
  orangefs: convert get_user_pages() --> pin_user_pages()
  orangefs: remove redundant assignment to variable ret
@pull pull bot added the ⤵️ pull label Jun 6, 2020
@pull pull bot merged commit aaa2faa into bergwolf:master Jun 6, 2020
pull bot pushed a commit that referenced this pull request Aug 16, 2020
…card()

If create a loop device with a backing NVMe SSD, current loop device
driver doesn't correctly set its  queue's limits.discard_granularity and
leaves it as 0. If a discard request at LBA 0 on this loop device, in
__blkdev_issue_discard() the calculated req_sects will be 0, and a zero
length discard request will trigger a BUG() panic in generic block layer
code at block/blk-mq.c:563.

[  955.565006][   C39] ------------[ cut here ]------------
[  955.559660][   C39] invalid opcode: 0000 [#1] SMP NOPTI
[  955.622171][   C39] CPU: 39 PID: 248 Comm: ksoftirqd/39 Tainted: G            E     5.8.0-default+ #40
[  955.622171][   C39] Hardware name: Lenovo ThinkSystem SR650 -[7X05CTO1WW]-/-[7X05CTO1WW]-, BIOS -[IVE160M-2.70]- 07/17/2020
[  955.622175][   C39] RIP: 0010:blk_mq_end_request+0x107/0x110
[  955.622177][   C39] Code: 48 8b 03 e9 59 ff ff ff 48 89 df 5b 5d 41 5c e9 9f ed ff ff 48 8b 35 98 3c f4 00 48 83 c7 10 48 83 c6 19 e8 cb 56 c9 ff eb cb <0f> 0b 0f 1f 80 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 56 41 54
[  955.622179][   C39] RSP: 0018:ffffb1288701fe28 EFLAGS: 00010202
[  955.749277][   C39] RAX: 0000000000000001 RBX: ffff956fffba5080 RCX: 0000000000004003
[  955.749278][   C39] RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000000
[  955.749279][   C39] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[  955.749279][   C39] R10: ffffb1288701fd28 R11: 0000000000000001 R12: ffffffffa8e05160
[  955.749280][   C39] R13: 0000000000000004 R14: 0000000000000004 R15: ffffffffa7ad3a1e
[  955.749281][   C39] FS:  0000000000000000(0000) GS:ffff95bfbda00000(0000) knlGS:0000000000000000
[  955.749282][   C39] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  955.749282][   C39] CR2: 00007f6f0ef766a8 CR3: 0000005a37012002 CR4: 00000000007606e0
[  955.749283][   C39] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  955.749284][   C39] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  955.749284][   C39] PKRU: 55555554
[  955.749285][   C39] Call Trace:
[  955.749290][   C39]  blk_done_softirq+0x99/0xc0
[  957.550669][   C39]  __do_softirq+0xd3/0x45f
[  957.550677][   C39]  ? smpboot_thread_fn+0x2f/0x1e0
[  957.550679][   C39]  ? smpboot_thread_fn+0x74/0x1e0
[  957.550680][   C39]  ? smpboot_thread_fn+0x14e/0x1e0
[  957.550684][   C39]  run_ksoftirqd+0x30/0x60
[  957.550687][   C39]  smpboot_thread_fn+0x149/0x1e0
[  957.886225][   C39]  ? sort_range+0x20/0x20
[  957.886226][   C39]  kthread+0x137/0x160
[  957.886228][   C39]  ? kthread_park+0x90/0x90
[  957.886231][   C39]  ret_from_fork+0x22/0x30
[  959.117120][   C39] ---[ end trace 3dacdac97e2ed164 ]---

This is the procedure to reproduce the panic,
  # modprobe scsi_debug delay=0 dev_size_mb=2048 max_queue=1
  # losetup -f /dev/nvme0n1 --direct-io=on
  # blkdiscard /dev/loop0 -o 0 -l 0x200

This patch fixes the issue by checking q->limits.discard_granularity in
__blkdev_issue_discard() before composing the discard bio. If the value
is 0, then prints a warning oops information and returns -EOPNOTSUPP to
the caller to indicate that this buggy device driver doesn't support
discard request.

Fixes: 9b15d10 ("block: improve discard bio alignment in __blkdev_issue_discard()")
Fixes: c52abf5 ("loop: Better discard support for block devices")
Reported-and-suggested-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Enzo Matsumiya <ematsumiya@suse.com>
Cc: Evan Green <evgreen@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Xiao Ni <xni@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
pull bot pushed a commit that referenced this pull request May 5, 2021
Ritesh reported a bug [1] against UML, noting that it crashed on
startup. The backtrace shows the following (heavily redacted):

(gdb) bt
...
 #26 0x0000000060015b5d in sem_init () at ipc/sem.c:268
 #27 0x00007f89906d92f7 in ?? () from /lib/x86_64-linux-gnu/libcom_err.so.2
 #28 0x00007f8990ab8fb2 in call_init (...) at dl-init.c:72
...
 #40 0x00007f89909bf3a6 in nss_load_library (...) at nsswitch.c:359
...
 #44 0x00007f8990895e35 in _nss_compat_getgrnam_r (...) at nss_compat/compat-grp.c:486
 #45 0x00007f8990968b85 in __getgrnam_r [...]
 #46 0x00007f89909d6b77 in grantpt [...]
 #47 0x00007f8990a9394e in __GI_openpty [...]
 #48 0x00000000604a1f65 in openpty_cb (...) at arch/um/os-Linux/sigio.c:407
 #49 0x00000000604a58d0 in start_idle_thread (...) at arch/um/os-Linux/skas/process.c:598
 #50 0x0000000060004a3d in start_uml () at arch/um/kernel/skas/process.c:45
 #51 0x00000000600047b2 in linux_main (...) at arch/um/kernel/um_arch.c:334
 #52 0x000000006000574f in main (...) at arch/um/os-Linux/main.c:144

indicating that the UML function openpty_cb() calls openpty(),
which internally calls __getgrnam_r(), which causes the nsswitch
machinery to get started.

This loads, through lots of indirection that I snipped, the
libcom_err.so.2 library, which (in an unknown function, "??")
calls sem_init().

Now, of course it wants to get libpthread's sem_init(), since
it's linked against libpthread. However, the dynamic linker
looks up that symbol against the binary first, and gets the
kernel's sem_init().

Hajime Tazaki noted that "objcopy -L" can localize a symbol,
so the dynamic linker wouldn't do the lookup this way. I tried,
but for some reason that didn't seem to work.

Doing the same thing in the linker script instead does seem to
work, though I cannot entirely explain - it *also* works if I
just add "VERSION { { global: *; }; }" instead, indicating that
something else is happening that I don't really understand. It
may be that explicitly doing that marks them with some kind of
empty version, and that's different from the default.

Explicitly marking them with a version breaks kallsyms, so that
doesn't seem to be possible.

Marking all the symbols as local seems correct, and does seem
to address the issue, so do that. Also do it for static link,
nsswitch libraries could still be loaded there.

[1] https://bugs.debian.org/983379

Reported-by: Ritesh Raj Sarraf <rrs@debian.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Tested-By: Ritesh Raj Sarraf <rrs@debian.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
pull bot pushed a commit that referenced this pull request Jul 3, 2021
The "auxtrace_info" and "auxtrace" functions are not set in "tool" member of
"annotate". As a result, perf annotate does not support parsing itrace data.

Before:

  # perf record -e arm_spe_0/branch_filter=1/ -a sleep 1
  [ perf record: Woken up 9 times to write data ]
  [ perf record: Captured and wrote 20.874 MB perf.data ]
  # perf annotate --stdio
  Error:
  The perf.data data has no samples!

Solution:

1. Add itrace options in help,
2. Set hook functions of "id_index", "auxtrace_info" and "auxtrace" in perf_tool.

After:

  # perf record --all-user -e arm_spe_0/branch_filter=1/ ls
  Couldn't synthesize bpf events.
  perf.data
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.010 MB perf.data ]
  # perf annotate --stdio
   Percent |      Source code & Disassembly of libc-2.28.so for branch-miss (1 samples, percent: local period)
  ------------------------------------------------------------------------------------------------------------
           :
           :
           :
           :           Disassembly of section .text:
           :
           :           0000000000066180 <__getdelim@@GLIBC_2.17>:
      0.00 :   66180:  stp     x29, x30, [sp, #-96]!
      0.00 :   66184:  cmp     x0, #0x0
      0.00 :   66188:  ccmp    x1, #0x0, #0x4, ne  // ne = any
      0.00 :   6618c:  mov     x29, sp
      0.00 :   66190:  stp     x24, x25, [sp, #56]
      0.00 :   66194:  stp     x26, x27, [sp, #72]
      0.00 :   66198:  str     x28, [sp, #88]
      0.00 :   6619c:  b.eq    66450 <__getdelim@@GLIBC_2.17+0x2d0>  // b.none
      0.00 :   661a0:  stp     x22, x23, [x29, #40]
      0.00 :   661a4:  mov     x22, x1
      0.00 :   661a8:  ldr     w1, [x3]
      0.00 :   661ac:  mov     w23, w2
      0.00 :   661b0:  stp     x20, x21, [x29, #24]
      0.00 :   661b4:  mov     x20, x3
      0.00 :   661b8:  mov     x21, x0
      0.00 :   661bc:  tbnz    w1, #15, 66360 <__getdelim@@GLIBC_2.17+0x1e0>
      0.00 :   661c0:  ldr     x0, [x3, #136]
      0.00 :   661c4:  ldr     x2, [x0, #8]
      0.00 :   661c8:  str     x19, [x29, #16]
      0.00 :   661cc:  mrs     x19, tpidr_el0
      0.00 :   661d0:  sub     x19, x19, #0x700
      0.00 :   661d4:  cmp     x2, x19
      0.00 :   661d8:  b.eq    663f0 <__getdelim@@GLIBC_2.17+0x270>  // b.none
      0.00 :   661dc:  mov     w1, #0x1                        // #1
      0.00 :   661e0:  ldaxr   w2, [x0]
      0.00 :   661e4:  cmp     w2, #0x0
      0.00 :   661e8:  b.ne    661f4 <__getdelim@@GLIBC_2.17+0x74>  // b.any
      0.00 :   661ec:  stxr    w3, w1, [x0]
      0.00 :   661f0:  cbnz    w3, 661e0 <__getdelim@@GLIBC_2.17+0x60>
      0.00 :   661f4:  b.ne    66448 <__getdelim@@GLIBC_2.17+0x2c8>  // b.any
      0.00 :   661f8:  ldr     x0, [x20, #136]
      0.00 :   661fc:  ldr     w1, [x20]
      0.00 :   66200:  ldr     w2, [x0, #4]
      0.00 :   66204:  str     x19, [x0, #8]
      0.00 :   66208:  add     w2, w2, #0x1
      0.00 :   6620c:  str     w2, [x0, #4]
      0.00 :   66210:  tbnz    w1, #5, 66388 <__getdelim@@GLIBC_2.17+0x208>
      0.00 :   66214:  ldr     x19, [x29, #16]
      0.00 :   66218:  ldr     x0, [x21]
      0.00 :   6621c:  cbz     x0, 66228 <__getdelim@@GLIBC_2.17+0xa8>
      0.00 :   66220:  ldr     x0, [x22]
      0.00 :   66224:  cbnz    x0, 6623c <__getdelim@@GLIBC_2.17+0xbc>
      0.00 :   66228:  mov     x0, #0x78                       // #120
      0.00 :   6622c:  str     x0, [x22]
      0.00 :   66230:  bl      20710 <malloc@plt>
      0.00 :   66234:  str     x0, [x21]
      0.00 :   66238:  cbz     x0, 66428 <__getdelim@@GLIBC_2.17+0x2a8>
      0.00 :   6623c:  ldr     x27, [x20, #8]
      0.00 :   66240:  str     x19, [x29, #16]
      0.00 :   66244:  ldr     x19, [x20, #16]
      0.00 :   66248:  sub     x19, x19, x27
      0.00 :   6624c:  cmp     x19, #0x0
      0.00 :   66250:  b.le    66398 <__getdelim@@GLIBC_2.17+0x218>
      0.00 :   66254:  mov     x25, #0x0                       // #0
      0.00 :   66258:  b       662d8 <__getdelim@@GLIBC_2.17+0x158>
      0.00 :   6625c:  nop
      0.00 :   66260:  add     x24, x19, x25
      0.00 :   66264:  ldr     x3, [x22]
      0.00 :   66268:  add     x26, x24, #0x1
      0.00 :   6626c:  ldr     x0, [x21]
      0.00 :   66270:  cmp     x3, x26
      0.00 :   66274:  b.cs    6629c <__getdelim@@GLIBC_2.17+0x11c>  // b.hs, b.nlast
      0.00 :   66278:  lsl     x3, x3, #1
      0.00 :   6627c:  cmp     x3, x26
      0.00 :   66280:  csel    x26, x3, x26, cs  // cs = hs, nlast
      0.00 :   66284:  mov     x1, x26
      0.00 :   66288:  bl      206f0 <realloc@plt>
      0.00 :   6628c:  cbz     x0, 66438 <__getdelim@@GLIBC_2.17+0x2b8>
      0.00 :   66290:  str     x0, [x21]
      0.00 :   66294:  ldr     x27, [x20, #8]
      0.00 :   66298:  str     x26, [x22]
      0.00 :   6629c:  mov     x2, x19
      0.00 :   662a0:  mov     x1, x27
      0.00 :   662a4:  add     x0, x0, x25
      0.00 :   662a8:  bl      87390 <explicit_bzero@@GLIBC_2.25+0x50>
      0.00 :   662ac:  ldr     x0, [x20, #8]
      0.00 :   662b0:  add     x19, x0, x19
      0.00 :   662b4:  str     x19, [x20, #8]
      0.00 :   662b8:  cbnz    x28, 66410 <__getdelim@@GLIBC_2.17+0x290>
      0.00 :   662bc:  mov     x0, x20
      0.00 :   662c0:  bl      73b80 <__underflow@@GLIBC_2.17>
      0.00 :   662c4:  cmn     w0, #0x1
      0.00 :   662c8:  b.eq    66410 <__getdelim@@GLIBC_2.17+0x290>  // b.none
      0.00 :   662cc:  ldp     x27, x19, [x20, #8]
      0.00 :   662d0:  mov     x25, x24
      0.00 :   662d4:  sub     x19, x19, x27
      0.00 :   662d8:  mov     x2, x19
      0.00 :   662dc:  mov     w1, w23
      0.00 :   662e0:  mov     x0, x27
      0.00 :   662e4:  bl      807b0 <memchr@@GLIBC_2.17>
      0.00 :   662e8:  cmp     x0, #0x0
      0.00 :   662ec:  mov     x28, x0
      0.00 :   662f0:  sub     x0, x0, x27
      0.00 :   662f4:  csinc   x19, x19, x0, eq  // eq = none
      0.00 :   662f8:  mov     x0, #0x7fffffffffffffff         // #9223372036854775807
      0.00 :   662fc:  sub     x0, x0, x25
      0.00 :   66300:  cmp     x19, x0
      0.00 :   66304:  b.lt    66260 <__getdelim@@GLIBC_2.17+0xe0>  // b.tstop
      0.00 :   66308:  adrp    x0, 17f000 <sys_sigabbrev@@GLIBC_2.17+0x320>
      0.00 :   6630c:  ldr     x0, [x0, #3624]
      0.00 :   66310:  mrs     x2, tpidr_el0
      0.00 :   66314:  ldr     x19, [x29, #16]
      0.00 :   66318:  mov     w3, #0x4b                       // #75
      0.00 :   6631c:  ldr     w1, [x20]
      0.00 :   66320:  mov     x24, #0xffffffffffffffff        // #-1
      0.00 :   66324:  str     w3, [x2, x0]
      0.00 :   66328:  tbnz    w1, #15, 66340 <__getdelim@@GLIBC_2.17+0x1c0>
      0.00 :   6632c:  ldr     x0, [x20, #136]
      0.00 :   66330:  ldr     w1, [x0, #4]
      0.00 :   66334:  sub     w1, w1, #0x1
      0.00 :   66338:  str     w1, [x0, #4]
      0.00 :   6633c:  cbz     w1, 663b8 <__getdelim@@GLIBC_2.17+0x238>
      0.00 :   66340:  mov     x0, x24
      0.00 :   66344:  ldr     x28, [sp, #88]
      0.00 :   66348:  ldp     x20, x21, [x29, #24]
      0.00 :   6634c:  ldp     x22, x23, [x29, #40]
      0.00 :   66350:  ldp     x24, x25, [sp, #56]
      0.00 :   66354:  ldp     x26, x27, [sp, #72]
      0.00 :   66358:  ldp     x29, x30, [sp], #96
      0.00 :   6635c:  ret
    100.00 :   66360:  tbz     w1, #5, 66218 <__getdelim@@GLIBC_2.17+0x98>
      0.00 :   66364:  ldp     x20, x21, [x29, #24]
      0.00 :   66368:  mov     x24, #0xffffffffffffffff        // #-1
      0.00 :   6636c:  ldp     x22, x23, [x29, #40]
      0.00 :   66370:  mov     x0, x24
      0.00 :   66374:  ldp     x24, x25, [sp, #56]
      0.00 :   66378:  ldp     x26, x27, [sp, #72]
      0.00 :   6637c:  ldr     x28, [sp, #88]
      0.00 :   66380:  ldp     x29, x30, [sp], #96
      0.00 :   66384:  ret
      0.00 :   66388:  mov     x24, #0xffffffffffffffff        // #-1
      0.00 :   6638c:  ldr     x19, [x29, #16]
      0.00 :   66390:  b       66328 <__getdelim@@GLIBC_2.17+0x1a8>
      0.00 :   66394:  nop
      0.00 :   66398:  mov     x0, x20
      0.00 :   6639c:  bl      73b80 <__underflow@@GLIBC_2.17>
      0.00 :   663a0:  cmn     w0, #0x1
      0.00 :   663a4:  b.eq    66438 <__getdelim@@GLIBC_2.17+0x2b8>  // b.none
      0.00 :   663a8:  ldp     x27, x19, [x20, #8]
      0.00 :   663ac:  sub     x19, x19, x27
      0.00 :   663b0:  b       66254 <__getdelim@@GLIBC_2.17+0xd4>
      0.00 :   663b4:  nop
      0.00 :   663b8:  str     xzr, [x0, #8]
      0.00 :   663bc:  ldxr    w2, [x0]
      0.00 :   663c0:  stlxr   w3, w1, [x0]
      0.00 :   663c4:  cbnz    w3, 663bc <__getdelim@@GLIBC_2.17+0x23c>
      0.00 :   663c8:  cmp     w2, #0x1
      0.00 :   663cc:  b.le    66340 <__getdelim@@GLIBC_2.17+0x1c0>
      0.00 :   663d0:  mov     x1, #0x81                       // #129
      0.00 :   663d4:  mov     x2, #0x1                        // #1
      0.00 :   663d8:  mov     x3, #0x0                        // #0
      0.00 :   663dc:  mov     x8, #0x62                       // #98
      0.00 :   663e0:  svc     #0x0
      0.00 :   663e4:  ldp     x20, x21, [x29, #24]
      0.00 :   663e8:  ldp     x22, x23, [x29, #40]
      0.00 :   663ec:  b       66370 <__getdelim@@GLIBC_2.17+0x1f0>
      0.00 :   663f0:  ldr     w2, [x0, #4]
      0.00 :   663f4:  add     w2, w2, #0x1
      0.00 :   663f8:  str     w2, [x0, #4]
      0.00 :   663fc:  tbz     w1, #5, 66214 <__getdelim@@GLIBC_2.17+0x94>
      0.00 :   66400:  mov     x24, #0xffffffffffffffff        // #-1
      0.00 :   66404:  ldr     x19, [x29, #16]
      0.00 :   66408:  b       66330 <__getdelim@@GLIBC_2.17+0x1b0>
      0.00 :   6640c:  nop
      0.00 :   66410:  ldr     x0, [x21]
      0.00 :   66414:  strb    wzr, [x0, x24]
      0.00 :   66418:  ldr     w1, [x20]
      0.00 :   6641c:  ldr     x19, [x29, #16]
      0.00 :   66420:  b       66328 <__getdelim@@GLIBC_2.17+0x1a8>
      0.00 :   66424:  nop
      0.00 :   66428:  mov     x24, #0xffffffffffffffff        // #-1
      0.00 :   6642c:  ldr     w1, [x20]
      0.00 :   66430:  b       66328 <__getdelim@@GLIBC_2.17+0x1a8>
      0.00 :   66434:  nop
      0.00 :   66438:  mov     x24, #0xffffffffffffffff        // #-1
      0.00 :   6643c:  ldr     w1, [x20]
      0.00 :   66440:  ldr     x19, [x29, #16]
      0.00 :   66444:  b       66328 <__getdelim@@GLIBC_2.17+0x1a8>
      0.00 :   66448:  bl      e3ba0 <pthread_setcanceltype@@GLIBC_2.17+0x30>
      0.00 :   6644c:  b       661f8 <__getdelim@@GLIBC_2.17+0x78>
      0.00 :   66450:  adrp    x0, 17f000 <sys_sigabbrev@@GLIBC_2.17+0x320>
      0.00 :   66454:  ldr     x0, [x0, #3624]
      0.00 :   66458:  mrs     x1, tpidr_el0
      0.00 :   6645c:  mov     w2, #0x16                       // #22
      0.00 :   66460:  mov     x24, #0xffffffffffffffff        // #-1
      0.00 :   66464:  str     w2, [x1, x0]
      0.00 :   66468:  b       66370 <__getdelim@@GLIBC_2.17+0x1f0>
      0.00 :   6646c:  ldr     w1, [x20]
      0.00 :   66470:  mov     x4, x0
      0.00 :   66474:  tbnz    w1, #15, 6648c <__getdelim@@GLIBC_2.17+0x30c>
      0.00 :   66478:  ldr     x0, [x20, #136]
      0.00 :   6647c:  ldr     w1, [x0, #4]
      0.00 :   66480:  sub     w1, w1, #0x1
      0.00 :   66484:  str     w1, [x0, #4]
      0.00 :   66488:  cbz     w1, 66494 <__getdelim@@GLIBC_2.17+0x314>
      0.00 :   6648c:  mov     x0, x4
      0.00 :   66490:  bl      20e40 <gnu_get_libc_version@@GLIBC_2.17+0x130>
      0.00 :   66494:  str     xzr, [x0, #8]
      0.00 :   66498:  ldxr    w2, [x0]
      0.00 :   6649c:  stlxr   w3, w1, [x0]
      0.00 :   664a0:  cbnz    w3, 66498 <__getdelim@@GLIBC_2.17+0x318>
      0.00 :   664a4:  cmp     w2, #0x1
      0.00 :   664a8:  b.le    6648c <__getdelim@@GLIBC_2.17+0x30c>
      0.00 :   664ac:  mov     x1, #0x81                       // #129
      0.00 :   664b0:  mov     x2, #0x1                        // #1
      0.00 :   664b4:  mov     x3, #0x0                        // #0
      0.00 :   664b8:  mov     x8, #0x62                       // #98
      0.00 :   664bc:  svc     #0x0
      0.00 :   664c0:  b       6648c <__getdelim@@GLIBC_2.17+0x30c>

Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210615091704.259202-1-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
pull bot pushed a commit that referenced this pull request Aug 22, 2021
…king KUEP

Commit b5efec0 ("powerpc/32s: Move KUEP locking/unlocking in C")
removed the 'isync' instruction after adding/removing NX bit in user
segments. The reasoning behind this change was that when setting the
NX bit we don't mind it taking effect with delay as the kernel never
executes text from userspace, and when clearing the NX bit this is
to return to userspace and then the 'rfi' should synchronise the
context.

However, it looks like on book3s/32 having a hash page table, at least
on the G3 processor, we get an unexpected fault from userspace, then
this is followed by something wrong in the verification of MSR_PR
at end of another interrupt.

This is fixed by adding back the removed isync() following update
of NX bit in user segment registers. Only do it for cores with an
hash table, as 603 cores don't exhibit that problem and the two isync
increase ./null_syscall selftest by 6 cycles on an MPC 832x.

First problem: unexpected WARN_ON() for mysterious PROTFAULT

  WARNING: CPU: 0 PID: 1660 at arch/powerpc/mm/fault.c:354 do_page_fault+0x6c/0x5b0
  Modules linked in:
  CPU: 0 PID: 1660 Comm: Xorg Not tainted 5.13.0-pmac-00028-gb3c15b60339a #40
  NIP:  c001b5c8 LR: c001b6f8 CTR: 00000000
  REGS: e2d09e40 TRAP: 0700   Not tainted  (5.13.0-pmac-00028-gb3c15b60339a)
  MSR:  00021032 <ME,IR,DR,RI>  CR: 42d04f30  XER: 20000000
  GPR00: c000424c e2d09f00 c301b680 e2d09f40 0000001e 42000000 00cba028 00000000
  GPR08: 08000000 48000010 c301b680 e2d09f30 22d09f30 00c1fff0 00cba000 a7b7ba4c
  GPR16: 00000031 00000000 00000000 00000000 00000000 00000000 a7b7b0d0 00c5c010
  GPR24: a7b7b64c a7b7d2f0 00000004 00000000 c1efa6c0 00cba02c 00000300 e2d09f40
  NIP [c001b5c8] do_page_fault+0x6c/0x5b0
  LR [c001b6f8] do_page_fault+0x19c/0x5b0
  Call Trace:
  [e2d09f00] [e2d09f04] 0xe2d09f04 (unreliable)
  [e2d09f30] [c000424c] DataAccess_virt+0xd4/0xe4
  --- interrupt: 300 at 0xa7a261dc
  NIP:  a7a261dc LR: a7a253bc CTR: 00000000
  REGS: e2d09f40 TRAP: 0300   Not tainted  (5.13.0-pmac-00028-gb3c15b60339a)
  MSR:  0000d032 <EE,PR,ME,IR,DR,RI>  CR: 228428e2  XER: 20000000
  DAR: 00cba02c DSISR: 42000000
  GPR00: a7a27448 afa6b0e0 a74c35c0 a7b7b614 0000001e a7b7b614 00cba028 00000000
  GPR08: 00020fd9 00000031 00cb9ff8 a7a273b0 220028e2 00c1fff0 00cba000 a7b7ba4c
  GPR16: 00000031 00000000 00000000 00000000 00000000 00000000 a7b7b0d0 00c5c010
  GPR24: a7b7b64c a7b7d2f0 00000004 00000002 0000001e a7b7b614 a7b7aff4 00000030
  NIP [a7a261dc] 0xa7a261dc
  LR [a7a253bc] 0xa7a253bc
  --- interrupt: 300
  Instruction dump:
  7c4a1378 810300a0 75278410 83820298 83a300a4 553b018c 551e0036 4082038c
  2e1b0000 40920228 75280800 41820220 <0fe00000> 3b600000 41920214 81420594

Second problem: MSR PR is seen unset allthough the interrupt frame shows it set

  kernel BUG at arch/powerpc/kernel/interrupt.c:458!
  Oops: Exception in kernel mode, sig: 5 [#1]
  BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 PowerMac
  Modules linked in:
  CPU: 0 PID: 1660 Comm: Xorg Tainted: G        W         5.13.0-pmac-00028-gb3c15b60339a #40
  NIP:  c0011434 LR: c001629c CTR: 00000000
  REGS: e2d09e70 TRAP: 0700   Tainted: G        W          (5.13.0-pmac-00028-gb3c15b60339a)
  MSR:  00029032 <EE,ME,IR,DR,RI>  CR: 42d09f30  XER: 00000000
  GPR00: 00000000 e2d09f30 c301b680 e2d09f40 83440000 c44d0e68 e2d09e8c 00000000
  GPR08: 00000002 00dc228a 00004000 e2d09f30 22d09f30 00c1fff0 afa6ceb4 00c26144
  GPR16: 00c25fb8 00c26140 afa6ceb8 90000000 00c944d8 0000001c 00000000 00200000
  GPR24: 00000000 000001fb afa6d1b4 00000001 00000000 a539a2a0 a530fd80 00000089
  NIP [c0011434] interrupt_exit_kernel_prepare+0x10/0x70
  LR [c001629c] interrupt_return+0x9c/0x144
  Call Trace:
  [e2d09f30] [c000424c] DataAccess_virt+0xd4/0xe4 (unreliable)
  --- interrupt: 300 at 0xa09be008
  NIP:  a09be008 LR: a09bdfe8 CTR: a09bdfc0
  REGS: e2d09f40 TRAP: 0300   Tainted: G        W          (5.13.0-pmac-00028-gb3c15b60339a)
  MSR:  0000d032 <EE,PR,ME,IR,DR,RI>  CR: 420028e2  XER: 20000000
  DAR: a539a308 DSISR: 0a000000
  GPR00: a7b90d50 afa6b2d0 a74c35c0 a0a8b690 a0a8b698 a5365d70 a4fa82a8 00000004
  GPR08: 00000000 a09bdfc0 00000000 a5360000 a09bde7c 00c1fff0 afa6ceb4 00c26144
  GPR16: 00c25fb8 00c26140 afa6ceb8 90000000 00c944d8 0000001c 00000000 00200000
  GPR24: 00000000 000001fb afa6d1b4 00000001 00000000 a539a2a0 a530fd80 00000089
  NIP [a09be008] 0xa09be008
  LR [a09bdfe8] 0xa09bdfe8
  --- interrupt: 300
  Instruction dump:
  80010024 83e1001c 7c0803a6 4bffff80 3bc00800 4bffffd0 486b42fd 4bffffcc
  81430084 71480002 41820038 554a0462 <0f0a0000> 80620060 74630001 40820034

Fixes: b5efec0 ("powerpc/32s: Move KUEP locking/unlocking in C")
Cc: stable@vger.kernel.org # v5.13+
Reported-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4856f5574906e2aec0522be17bf3848a22b2cd0b.1629269345.git.christophe.leroy@csgroup.eu
pull bot pushed a commit that referenced this pull request Apr 3, 2022
…frame()

The following KASAN warning is detected by QEMU.

==================================================================
BUG: KASAN: stack-out-of-bounds in unwind_frame+0x508/0x870
Read of size 4 at addr c36bba90 by task cat/163

CPU: 1 PID: 163 Comm: cat Not tainted 5.10.0-rc1 #40
Hardware name: ARM-Versatile Express
[<c0113fac>] (unwind_backtrace) from [<c010e71c>] (show_stack+0x10/0x14)
[<c010e71c>] (show_stack) from [<c0b805b4>] (dump_stack+0x98/0xb0)
[<c0b805b4>] (dump_stack) from [<c0b7d658>] (print_address_description.constprop.0+0x58/0x4bc)
[<c0b7d658>] (print_address_description.constprop.0) from [<c031435c>] (kasan_report+0x154/0x170)
[<c031435c>] (kasan_report) from [<c0113c44>] (unwind_frame+0x508/0x870)
[<c0113c44>] (unwind_frame) from [<c010e298>] (__save_stack_trace+0x110/0x134)
[<c010e298>] (__save_stack_trace) from [<c01ce0d8>] (stack_trace_save+0x8c/0xb4)
[<c01ce0d8>] (stack_trace_save) from [<c0313520>] (kasan_set_track+0x38/0x60)
[<c0313520>] (kasan_set_track) from [<c0314cb8>] (kasan_set_free_info+0x20/0x2c)
[<c0314cb8>] (kasan_set_free_info) from [<c0313474>] (__kasan_slab_free+0xec/0x120)
[<c0313474>] (__kasan_slab_free) from [<c0311e20>] (kmem_cache_free+0x7c/0x334)
[<c0311e20>] (kmem_cache_free) from [<c01c35dc>] (rcu_core+0x390/0xccc)
[<c01c35dc>] (rcu_core) from [<c01013a8>] (__do_softirq+0x180/0x518)
[<c01013a8>] (__do_softirq) from [<c0135214>] (irq_exit+0x9c/0xe0)
[<c0135214>] (irq_exit) from [<c01a40e4>] (__handle_domain_irq+0xb0/0x110)
[<c01a40e4>] (__handle_domain_irq) from [<c0691248>] (gic_handle_irq+0xa0/0xb8)
[<c0691248>] (gic_handle_irq) from [<c0100b0c>] (__irq_svc+0x6c/0x94)
Exception stack(0xc36bb928 to 0xc36bb970)
b920:                   c36bb9c0 00000000 c0126919 c0101228 c36bb9c0 b76d7730
b940: c36b8000 c36bb9a0 c3335b00 c01ce0d8 00000003 c36bba3c c36bb940 c36bb978
b960: c010e298 c011373c 60000013 ffffffff
[<c0100b0c>] (__irq_svc) from [<c011373c>] (unwind_frame+0x0/0x870)
[<c011373c>] (unwind_frame) from [<00000000>] (0x0)

The buggy address belongs to the page:
page:(ptrval) refcount:0 mapcount:0 mapping:00000000 index:0x0 pfn:0x636bb
flags: 0x0()
raw: 00000000 00000000 ef867764 00000000 00000000 00000000 ffffffff 00000000
page dumped because: kasan: bad access detected

addr c36bba90 is located in stack of task cat/163 at offset 48 in frame:
 stack_trace_save+0x0/0xb4

this frame has 1 object:
 [32, 48) 'trace'

Memory state around the buggy address:
 c36bb980: f1 f1 f1 f1 00 04 f2 f2 00 00 f3 f3 00 00 00 00
 c36bba00: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
>c36bba80: 00 00 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
                 ^
 c36bbb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 c36bbb80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

There is a same issue on x86 and has been resolved by the commit f7d27c3
("x86/mm, kasan: Silence KASAN warnings in get_wchan()").
The solution could be applied to arm architecture too.

Signed-off-by: Lin Yujun <linyujun809@huawei.com>
Reported-by: He Ying <heying24@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
pull bot pushed a commit that referenced this pull request Dec 12, 2022
We use uprobe in aarch64_be, which we found the tracee task would exit
due to SIGILL when we enable the uprobe trace.
We can see the replace inst from uprobe is not correct in aarch big-endian.
As in Armv8-A, instruction fetches are always treated as little-endian,
we should treat the UPROBE_SWBP_INSN as little-endian。

The test case is as following。
bash-4.4# ./mqueue_test_aarchbe 1 1 2 1 10 > /dev/null &
bash-4.4# cd /sys/kernel/debug/tracing/
bash-4.4# echo 'p:test /mqueue_test_aarchbe:0xc30 %x0 %x1' > uprobe_events
bash-4.4# echo 1 > events/uprobes/enable
bash-4.4#
bash-4.4# ps
  PID TTY          TIME CMD
  140 ?        00:00:01 bash
  237 ?        00:00:00 ps
[1]+  Illegal instruction     ./mqueue_test_aarchbe 1 1 2 1 100 > /dev/null

which we debug use gdb as following:

bash-4.4# gdb attach 155
(gdb) disassemble send
Dump of assembler code for function send:
   0x0000000000400c30 <+0>:     .inst   0xa00020d4 ; undefined
   0x0000000000400c34 <+4>:     mov     x29, sp
   0x0000000000400c38 <+8>:     str     w0, [sp, #28]
   0x0000000000400c3c <+12>:    strb    w1, [sp, #27]
   0x0000000000400c40 <+16>:    str     xzr, [sp, #40]
   0x0000000000400c44 <+20>:    str     xzr, [sp, #48]
   0x0000000000400c48 <+24>:    add     x0, sp, #0x1b
   0x0000000000400c4c <+28>:    mov     w3, #0x0                 // #0
   0x0000000000400c50 <+32>:    mov     x2, #0x1                 // #1
   0x0000000000400c54 <+36>:    mov     x1, x0
   0x0000000000400c58 <+40>:    ldr     w0, [sp, #28]
   0x0000000000400c5c <+44>:    bl      0x405e10 <mq_send>
   0x0000000000400c60 <+48>:    str     w0, [sp, #60]
   0x0000000000400c64 <+52>:    ldr     w0, [sp, #60]
   0x0000000000400c68 <+56>:    ldp     x29, x30, [sp], #64
   0x0000000000400c6c <+60>:    ret
End of assembler dump.
(gdb) info b
No breakpoints or watchpoints.
(gdb) c
Continuing.

Program received signal SIGILL, Illegal instruction.
0x0000000000400c30 in send ()
(gdb) x/10x 0x400c30
0x400c30 <send>:    0xd42000a0   0xfd030091      0xe01f00b9      0xe16f0039
0x400c40 <send+16>: 0xff1700f9   0xff1b00f9      0xe06f0091      0x03008052
0x400c50 <send+32>: 0x220080d2   0xe10300aa
(gdb) disassemble 0x400c30
Dump of assembler code for function send:
=> 0x0000000000400c30 <+0>:     .inst   0xa00020d4 ; undefined
   0x0000000000400c34 <+4>:     mov     x29, sp
   0x0000000000400c38 <+8>:     str     w0, [sp, #28]
   0x0000000000400c3c <+12>:    strb    w1, [sp, #27]
   0x0000000000400c40 <+16>:    str     xzr, [sp, #40]

Signed-off-by: junhua huang <huang.junhua@zte.com.cn>
Link: https://lore.kernel.org/r/202212021511106844809@zte.com.cn
Signed-off-by: Will Deacon <will@kernel.org>
pull bot pushed a commit that referenced this pull request Sep 13, 2023
Inject fault while probing btrfs.ko, if kstrdup() fails in
eventfs_prepare_ef() in eventfs_add_dir(), it will return ERR_PTR
to assign file->ef. But the eventfs_remove() check NULL in
trace_module_remove_events(), which causes the below NULL
pointer dereference.

As both Masami and Steven suggest, allocater side should handle the
error carefully and remove it, so fix the places where it failed.

 Could not create tracefs 'raid56_write' directory
 Btrfs loaded, zoned=no, fsverity=no
 Unable to handle kernel NULL pointer dereference at virtual address 000000000000001c
 Mem abort info:
   ESR = 0x0000000096000004
   EC = 0x25: DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
   FSC = 0x04: level 0 translation fault
 Data abort info:
   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
 user pgtable: 4k pages, 48-bit VAs, pgdp=0000000102544000
 [000000000000001c] pgd=0000000000000000, p4d=0000000000000000
 Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
 Dumping ftrace buffer:
    (ftrace buffer empty)
 Modules linked in: btrfs(-) libcrc32c xor xor_neon raid6_pq cfg80211 rfkill 8021q garp mrp stp llc ipv6 [last unloaded: btrfs]
 CPU: 15 PID: 1343 Comm: rmmod Tainted: G                 N 6.5.0+ #40
 Hardware name: linux,dummy-virt (DT)
 pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : eventfs_remove_rec+0x24/0xc0
 lr : eventfs_remove+0x68/0x1d8
 sp : ffff800082d63b60
 x29: ffff800082d63b60 x28: ffffb84b80ddd00c x27: ffffb84b3054ba40
 x26: 0000000000000002 x25: ffff800082d63bf8 x24: ffffb84b8398e440
 x23: ffffb84b82af3000 x22: dead000000000100 x21: dead000000000122
 x20: ffff800082d63bf8 x19: fffffffffffffff4 x18: ffffb84b82508820
 x17: 0000000000000000 x16: 0000000000000000 x15: 000083bc876a3166
 x14: 000000000000006d x13: 000000000000006d x12: 0000000000000000
 x11: 0000000000000001 x10: 00000000000017e0 x9 : 0000000000000001
 x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffffb84b84289804
 x5 : 0000000000000000 x4 : 9696969696969697 x3 : ffff33a5b7601f38
 x2 : 0000000000000000 x1 : ffff800082d63bf8 x0 : fffffffffffffff4
 Call trace:
  eventfs_remove_rec+0x24/0xc0
  eventfs_remove+0x68/0x1d8
  remove_event_file_dir+0x88/0x100
  event_remove+0x140/0x15c
  trace_module_notify+0x1fc/0x230
  notifier_call_chain+0x98/0x17c
  blocking_notifier_call_chain+0x4c/0x74
  __arm64_sys_delete_module+0x1a4/0x298
  invoke_syscall+0x44/0x100
  el0_svc_common.constprop.1+0x68/0xe0
  do_el0_svc+0x1c/0x28
  el0_svc+0x3c/0xc4
  el0t_64_sync_handler+0xa0/0xc4
  el0t_64_sync+0x174/0x178
 Code: 5400052c a90153b3 aa0003f3 aa0103f4 (f9401400)
 ---[ end trace 0000000000000000 ]---
 Kernel panic - not syncing: Oops: Fatal exception
 SMP: stopping secondary CPUs
 Dumping ftrace buffer:
    (ftrace buffer empty)
 Kernel Offset: 0x384b00c00000 from 0xffff800080000000
 PHYS_OFFSET: 0xffffcc5b80000000
 CPU features: 0x88000203,3c020000,1000421b
 Memory Limit: none
 Rebooting in 1 seconds..

Link: https://lore.kernel.org/linux-trace-kernel/20230912134752.1838524-1-ruanjinjie@huawei.com
Link: https://lore.kernel.org/all/20230912025808.668187-1-ruanjinjie@huawei.com/
Link: https://lore.kernel.org/all/20230911052818.1020547-1-ruanjinjie@huawei.com/
Link: https://lore.kernel.org/all/20230909072817.182846-1-ruanjinjie@huawei.com/
Link: https://lore.kernel.org/all/20230908074816.3724716-1-ruanjinjie@huawei.com/

Cc: Ajay Kaher <akaher@vmware.com>
Fixes: 5bdcd5f ("eventfs: Implement removal of meta data from eventfs")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
pull bot pushed a commit that referenced this pull request Feb 3, 2024
A last minute revert in 6.7-final introduced a potential deadlock when
enabling ASPM during probe of Qualcomm PCIe controllers as reported by
lockdep:

  ============================================
  WARNING: possible recursive locking detected
  6.7.0 #40 Not tainted
  --------------------------------------------
  kworker/u16:5/90 is trying to acquire lock:
  ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pcie_aspm_pm_state_change+0x58/0xdc

              but task is already holding lock:
  ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pci_walk_bus+0x34/0xbc

              other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(pci_bus_sem);
    lock(pci_bus_sem);

               *** DEADLOCK ***

  Call trace:
   print_deadlock_bug+0x25c/0x348
   __lock_acquire+0x10a4/0x2064
   lock_acquire+0x1e8/0x318
   down_read+0x60/0x184
   pcie_aspm_pm_state_change+0x58/0xdc
   pci_set_full_power_state+0xa8/0x114
   pci_set_power_state+0xc4/0x120
   qcom_pcie_enable_aspm+0x1c/0x3c [pcie_qcom]
   pci_walk_bus+0x64/0xbc
   qcom_pcie_host_post_init_2_7_0+0x28/0x34 [pcie_qcom]

The deadlock can easily be reproduced on machines like the Lenovo ThinkPad
X13s by adding a delay to increase the race window during asynchronous
probe where another thread can take a write lock.

Add a new pci_set_power_state_locked() and associated helper functions that
can be called with the PCI bus semaphore held to avoid taking the read lock
twice.

Link: https://lore.kernel.org/r/ZZu0qx2cmn7IwTyQ@hovoldconsulting.com
Link: https://lore.kernel.org/r/20240130100243.11011-1-johan+linaro@kernel.org
Fixes: f93e71a ("Revert "PCI/ASPM: Remove pcie_aspm_pm_state_change()"")
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: <stable@vger.kernel.org>	# 6.7
pull bot pushed a commit that referenced this pull request Aug 20, 2024
The queue stats API queries the queues according to the
real_num_[tr]x_queues, in case the device is down and channels were not
yet created, don't try to query their statistics.

To trigger the panic, run this command before the interface is brought
up:
./cli.py --spec ../../../Documentation/netlink/specs/netdev.yaml --dump qstats-get --json '{"ifindex": 4}'

BUG: kernel NULL pointer dereference, address: 0000000000000c00
PGD 0 P4D 0
Oops: Oops: 0000 [#1] SMP PTI
CPU: 3 UID: 0 PID: 977 Comm: python3 Not tainted 6.10.0+ #40
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:mlx5e_get_queue_stats_rx+0x3c/0xb0 [mlx5_core]
Code: fc 55 48 63 ee 53 48 89 d3 e8 40 3d 70 e1 85 c0 74 58 4c 89 ef e8 d4 07 04 00 84 c0 75 41 49 8b 84 24 f8 39 00 00 48 8b 04 e8 <48> 8b 90 00 0c 00 00 48 03 90 40 0a 00 00 48 89 53 08 48 8b 90 08
RSP: 0018:ffff888116be37d0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888116be3868 RCX: 0000000000000004
RDX: ffff88810ada4000 RSI: 0000000000000000 RDI: ffff888109df09c0
RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000000004
R10: ffff88813461901c R11: ffffffffffffffff R12: ffff888109df0000
R13: ffff888109df09c0 R14: ffff888116be38d0 R15: 0000000000000000
FS:  00007f4375d5c740(0000) GS:ffff88852c980000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000c00 CR3: 0000000106ada006 CR4: 0000000000370eb0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ? __die+0x1f/0x60
 ? page_fault_oops+0x14e/0x3d0
 ? exc_page_fault+0x73/0x130
 ? asm_exc_page_fault+0x22/0x30
 ? mlx5e_get_queue_stats_rx+0x3c/0xb0 [mlx5_core]
 netdev_nl_stats_by_netdev+0x2a6/0x4c0
 ? __rmqueue_pcplist+0x351/0x6f0
 netdev_nl_qstats_get_dumpit+0xc4/0x1b0
 genl_dumpit+0x2d/0x80
 netlink_dump+0x199/0x410
 __netlink_dump_start+0x1aa/0x2c0
 genl_family_rcv_msg_dumpit+0x94/0xf0
 ? __pfx_genl_start+0x10/0x10
 ? __pfx_genl_dumpit+0x10/0x10
 ? __pfx_genl_done+0x10/0x10
 genl_rcv_msg+0x116/0x2b0
 ? __pfx_netdev_nl_qstats_get_dumpit+0x10/0x10
 ? __pfx_genl_rcv_msg+0x10/0x10
 netlink_rcv_skb+0x54/0x100
 genl_rcv+0x24/0x40
 netlink_unicast+0x21a/0x340
 netlink_sendmsg+0x1f4/0x440
 __sys_sendto+0x1b6/0x1c0
 ? do_sock_setsockopt+0xc3/0x180
 ? __sys_setsockopt+0x60/0xb0
 __x64_sys_sendto+0x20/0x30
 do_syscall_64+0x50/0x110
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f43757132b0
Code: c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 1d 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 68 c3 0f 1f 80 00 00 00 00 41 54 48 83 ec 20
RSP: 002b:00007ffd258da048 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007ffd258da0f8 RCX: 00007f43757132b0
RDX: 000000000000001c RSI: 00007f437464b850 RDI: 0000000000000003
RBP: 00007f4375085de0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: ffffffffc4653600 R14: 0000000000000001 R15: 00007f43751a6147
 </TASK>
Modules linked in: netconsole xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xt_addrtype iptable_nat nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_registry overlay rpcrdma rdma_ucm ib_iser libiscsi scsi_transport_iscsi ib_umad rdma_cm ib_ipoib iw_cm ib_cm mlx5_ib ib_uverbs ib_core zram zsmalloc mlx5_core fuse [last unloaded: netconsole]
CR2: 0000000000000c00
---[ end trace 0000000000000000 ]---
RIP: 0010:mlx5e_get_queue_stats_rx+0x3c/0xb0 [mlx5_core]
Code: fc 55 48 63 ee 53 48 89 d3 e8 40 3d 70 e1 85 c0 74 58 4c 89 ef e8 d4 07 04 00 84 c0 75 41 49 8b 84 24 f8 39 00 00 48 8b 04 e8 <48> 8b 90 00 0c 00 00 48 03 90 40 0a 00 00 48 89 53 08 48 8b 90 08
RSP: 0018:ffff888116be37d0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888116be3868 RCX: 0000000000000004
RDX: ffff88810ada4000 RSI: 0000000000000000 RDI: ffff888109df09c0
RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000000004
R10: ffff88813461901c R11: ffffffffffffffff R12: ffff888109df0000
R13: ffff888109df09c0 R14: ffff888116be38d0 R15: 0000000000000000
FS:  00007f4375d5c740(0000) GS:ffff88852c980000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000c00 CR3: 0000000106ada006 CR4: 0000000000370eb0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Fixes: 7b66ae5 ("net/mlx5e: Add per queue netdev-genl stats")
Signed-off-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Link: https://patch.msgid.link/20240808144107.2095424-6-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Projects
None yet
Development

Successfully merging this pull request may close these issues.