The definition of the lowlink in Tarjan's algorithm is the
smallest index of a vertex that is reachable with at most one
back-edge in SCC. This is not useful for a cross-edge.
If we start traversing from A in the following graph, the final
lowlink of D is 3. The cross-edge here is one between D and C.
A -> B -> D D = (4, 3) (index, lowlink)
^ | | C = (3, 1)
| V | B = (2, 1)
`--- C <--' A = (1, 1)
This is because the lowlink of D is updated with the index of C.
In the following patch, we detect a dead SCC by checking two
conditions for each vertex.
1) vertex has no edge directed to another SCC (no bridge)
2) vertex's out_degree is the same as the refcount of its file
If 1) is false, there is a receiver of all fds of the SCC and
its ancestor SCC.
To evaluate 1), we need to assign a unique index to each SCC and
assign it to all vertices in the SCC.
This patch changes the lowlink update logic for cross-edge so
that in the example above, the lowlink of D is updated with the
lowlink of C.
A -> B -> D D = (4, 1) (index, lowlink)
^ | | C = (3, 1)
| V | B = (2, 1)
`--- C <--' A = (1, 1)
Then, all vertices in the same SCC have the same lowlink, and we
can quickly find the bridge connecting to different SCC if exists.
However, it is no longer called lowlink, so we rename it to
scc_index. (It's sometimes called lowpoint.)
Also, we add a global variable to hold the last index used in DFS
so that we do not reset the initial index in each DFS.
This patch can be squashed to the SCC detection patch but is
split deliberately for anyone wondering why lowlink is not used
as used in the original Tarjan's algorithm and many reference
implementations.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-13-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We do not need to run GC if there is no possible cyclic reference.
We use unix_graph_maybe_cyclic to decide if we should run GC.
If a fd of an AF_UNIX socket is passed to an already inflight AF_UNIX
socket, they could form a cyclic reference. Then, we set true to
unix_graph_maybe_cyclic and later run Tarjan's algorithm to group
them into SCC.
Once we run Tarjan's algorithm, we are 100% sure whether cyclic
references exist or not. If there is no cycle, we set false to
unix_graph_maybe_cyclic and can skip the entire garbage collection
next time.
When finalising SCC, we set true to unix_graph_maybe_cyclic if SCC
consists of multiple vertices.
Even if SCC is a single vertex, a cycle might exist as self-fd passing.
Given the corner case is rare, we detect it by checking all edges of
the vertex and set true to unix_graph_maybe_cyclic.
With this change, __unix_gc() is just a spin_lock() dance in the normal
usage.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-11-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Before starting Tarjan's algorithm, we need to mark all vertices
as unvisited. We can save this O(n) setup by reserving two special
indices (0, 1) and using two variables.
The first time we link a vertex to unix_unvisited_vertices, we set
unix_vertex_unvisited_index to index.
During DFS, we can see that the index of unvisited vertices is the
same as unix_vertex_unvisited_index.
When we finalise SCC later, we set unix_vertex_grouped_index to each
vertex's index.
Then, we can know (i) that the vertex is on the stack if the index
of a visited vertex is >= 2 and (ii) that it is not on the stack and
belongs to a different SCC if the index is unix_vertex_grouped_index.
After the whole algorithm, all indices of vertices are set as
unix_vertex_grouped_index.
Next time we start DFS, we know that all unvisited vertices have
unix_vertex_grouped_index, and we can use unix_vertex_unvisited_index
as the not-on-stack marker.
To use the same variable in __unix_walk_scc(), we can swap
unix_vertex_(grouped|unvisited)_index at the end of Tarjan's
algorithm.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-10-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To garbage collect inflight AF_UNIX sockets, we must define the
cyclic reference appropriately. This is a bit tricky if the loop
consists of embryo sockets.
Suppose that the fd of AF_UNIX socket A is passed to D and the fd B
to C and that C and D are embryo sockets of A and B, respectively.
It may appear that there are two separate graphs, A (-> D) and
B (-> C), but this is not correct.
A --. .-- B
X
C <-' `-> D
Now, D holds A's refcount, and C has B's refcount, so unix_release()
will never be called for A and B when we close() them. However, no
one can call close() for D and C to free skbs holding refcounts of A
and B because C/D is in A/B's receive queue, which should have been
purged by unix_release() for A and B.
So, here's another type of cyclic reference. When a fd of an AF_UNIX
socket is passed to an embryo socket, the reference is indirectly held
by its parent listening socket.
.-> A .-> B
| `- sk_receive_queue | `- sk_receive_queue
| `- skb | `- skb
| `- sk == C | `- sk == D
| `- sk_receive_queue | `- sk_receive_queue
| `- skb +---------' `- skb +-.
| |
`---------------------------------------------------------'
Technically, the graph must be denoted as A <-> B instead of A (-> D)
and B (-> C) to find such a cyclic reference without touching each
socket's receive queue.
.-> A --. .-- B <-.
| X | == A <-> B
`-- C <-' `-> D --'
We apply this fixup during GC by fetching the real successor by
unix_edge_successor().
When we call accept(), we clear unix_sock.listener under unix_gc_lock
not to confuse GC.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-9-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the new GC, we use a simple graph algorithm, Tarjan's Strongly
Connected Components (SCC) algorithm, to find cyclic references.
The algorithm visits every vertex exactly once using depth-first
search (DFS).
DFS starts by pushing an input vertex to a stack and assigning it
a unique number. Two fields, index and lowlink, are initialised
with the number, but lowlink could be updated later during DFS.
If a vertex has an edge to an unvisited inflight vertex, we visit
it and do the same processing. So, we will have vertices in the
stack in the order they appear and number them consecutively in
the same order.
If a vertex has a back-edge to a visited vertex in the stack,
we update the predecessor's lowlink with the successor's index.
After iterating edges from the vertex, we check if its index
equals its lowlink.
If the lowlink is different from the index, it shows there was a
back-edge. Then, we go backtracking and propagate the lowlink to
its predecessor and resume the previous edge iteration from the
next edge.
If the lowlink is the same as the index, we pop vertices before
and including the vertex from the stack. Then, the set of vertices
is SCC, possibly forming a cycle. At the same time, we move the
vertices to unix_visited_vertices.
When we finish the algorithm, all vertices in each SCC will be
linked via unix_vertex.scc_entry.
Let's take an example. We have a graph including five inflight
vertices (F is not inflight):
A -> B -> C -> D -> E (-> F)
^ |
`---------'
Suppose that we start DFS from C. We will visit C, D, and B first
and initialise their index and lowlink. Then, the stack looks like
this:
> B = (3, 3) (index, lowlink)
D = (2, 2)
C = (1, 1)
When checking B's edge to C, we update B's lowlink with C's index
and propagate it to D.
B = (3, 1) (index, lowlink)
> D = (2, 1)
C = (1, 1)
Next, we visit E, which has no edge to an inflight vertex.
> E = (4, 4) (index, lowlink)
B = (3, 1)
D = (2, 1)
C = (1, 1)
When we leave from E, its index and lowlink are the same, so we
pop E from the stack as single-vertex SCC. Next, we leave from
B and D but do nothing because their lowlink are different from
their index.
B = (3, 1) (index, lowlink)
D = (2, 1)
> C = (1, 1)
Then, we leave from C, whose index and lowlink are the same, so
we pop B, D and C as SCC.
Last, we do DFS for the rest of vertices, A, which is also a
single-vertex SCC.
Finally, each unix_vertex.scc_entry is linked as follows:
A -. B -> C -> D E -.
^ | ^ | ^ |
`--' `---------' `--'
We use SCC later to decide whether we can garbage-collect the
sockets.
Note that we still cannot detect SCC properly if an edge points
to an embryo socket. The following two patches will sort it out.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-7-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The new GC will use a depth first search graph algorithm to find
cyclic references. The algorithm visits every vertex exactly once.
Here, we implement the DFS part without recursion so that no one
can abuse it.
unix_walk_scc() marks every vertex unvisited by initialising index
as UNIX_VERTEX_INDEX_UNVISITED and iterates inflight vertices in
unix_unvisited_vertices and call __unix_walk_scc() to start DFS from
an arbitrary vertex.
__unix_walk_scc() iterates all edges starting from the vertex and
explores the neighbour vertices with DFS using edge_stack.
After visiting all neighbours, __unix_walk_scc() moves the visited
vertex to unix_visited_vertices so that unix_walk_scc() will not
restart DFS from the visited vertex.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-6-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, we track the number of inflight sockets in two variables.
unix_tot_inflight is the total number of inflight AF_UNIX sockets on
the host, and user->unix_inflight is the number of inflight fds per
user.
We update them one by one in unix_inflight(), which can be done once
in batch. Also, sendmsg() could fail even after unix_inflight(), then
we need to acquire unix_gc_lock only to decrement the counters.
Let's bulk update the counters in unix_add_edges() and unix_del_edges(),
which is called only for successfully passed fds.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-5-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Just before queuing skb with inflight fds, we call scm_stat_add(),
which is a good place to set up the preallocated struct unix_vertex
and struct unix_edge in UNIXCB(skb).fp.
Then, we call unix_add_edges() and construct the directed graph
as follows:
1. Set the inflight socket's unix_sock to unix_edge.predecessor.
2. Set the receiver's unix_sock to unix_edge.successor.
3. Set the preallocated vertex to inflight socket's unix_sock.vertex.
4. Link inflight socket's unix_vertex.entry to unix_unvisited_vertices.
5. Link unix_edge.vertex_entry to the inflight socket's unix_vertex.edges.
Let's say we pass the fd of AF_UNIX socket A to B and the fd of B
to C. The graph looks like this:
As with the previous patch, we preallocate to skb's scm_fp_list an
array of struct unix_edge in the number of inflight AF_UNIX fds.
There we just preallocate memory and do not use immediately because
sendmsg() could fail after this point. The actual use will be in
the next patch.
When we queue skb with inflight edges, we will set the inflight
socket's unix_sock as unix_edge->predecessor and the receiver's
unix_sock as successor, and then we will link the edge to the
inflight socket's unix_vertex.edges.
Note that we set NULL to cloned scm_fp_list.edges in scm_fp_dup()
so that MSG_PEEK does not change the shape of the directed graph.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-3-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We will replace the garbage collection algorithm for AF_UNIX, where
we will consider each inflight AF_UNIX socket as a vertex and its file
descriptor as an edge in a directed graph.
This patch introduces a new struct unix_vertex representing a vertex
in the graph and adds its pointer to struct unix_sock.
When we send a fd using the SCM_RIGHTS message, we allocate struct
scm_fp_list to struct scm_cookie in scm_fp_copy(). Then, we bump
each refcount of the inflight fds' struct file and save them in
scm_fp_list.fp.
After that, unix_attach_fds() inexplicably clones scm_fp_list of
scm_cookie and sets it to skb. (We will remove this part after
replacing GC.)
Here, we add a new function call in unix_attach_fds() to preallocate
struct unix_vertex per inflight AF_UNIX fd and link each vertex to
skb's scm_fp_list.vertices.
When sendmsg() succeeds later, if the socket of the inflight fd is
still not inflight yet, we will set the preallocated vertex to struct
unix_sock.vertex and link it to a global list unix_unvisited_vertices
under spin_lock(&unix_gc_lock).
If the socket is already inflight, we free the preallocated vertex.
This is to avoid taking the lock unnecessarily when sendmsg() could
fail later.
In the following patch, we will similarly allocate another struct
per edge, which will finally be linked to the inflight socket's
unix_vertex.edges.
And then, we will count the number of edges as unix_vertex.out_degree.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240325202425.60930-2-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Originally, the code related to garbage collection was all in garbage.c.
Commit f4e65870e5ce ("net: split out functions related to registering
inflight socket files") moved some functions to scm.c for io_uring and
added CONFIG_UNIX_SCM just in case AF_UNIX was built as module.
However, since commit 97154bcf4d1b ("af_unix: Kconfig: make CONFIG_UNIX
bool"), AF_UNIX is no longer built separately. Also, io_uring does not
support SCM_RIGHTS now.
Let's move the functions back to garbage.c
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20240129190435.57228-4-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit 705318a99a13 ("io_uring/af_unix: disable sending
io_uring over sockets"), io_uring's unix socket cannot be passed
via SCM_RIGHTS, so it does not contribute to cyclic reference and
no longer be candidate for garbage collection.
Also, commit 6e5e6d274956 ("io_uring: drop any code related to
SCM_RIGHTS") cleaned up SCM_RIGHTS code in io_uring.
Let's do it in AF_UNIX as well by reverting commit 0091bfc81741
("io_uring/af_unix: defer registered files gc to io_uring release")
and commit 10369080454d ("net: reclaim skb->scm_io_uring bit").
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20240129190435.57228-3-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If more than 16000 inflight AF_UNIX sockets exist and the garbage
collector is not running, unix_(dgram|stream)_sendmsg() call unix_gc().
Also, they wait for unix_gc() to complete.
In unix_gc(), all inflight AF_UNIX sockets are traversed at least once,
and more if they are the GC candidate. Thus, sendmsg() significantly
slows down with too many inflight AF_UNIX sockets.
However, if a process sends data with no AF_UNIX FD, the sendmsg() call
does not need to wait for GC. After this change, only the process that
meets the condition below will be blocked under such a situation.
1) cmsg contains AF_UNIX socket
2) more than 32 AF_UNIX sent by the same user are still inflight
Note that even a sendmsg() call that does not meet the condition but has
AF_UNIX FD will be blocked later in unix_scm_to_skb() by the spinlock,
but we allow that as a bonus for sane users.
The results below are the time spent in unix_dgram_sendmsg() sending 1
byte of data with no FD 4096 times on a host where 32K inflight AF_UNIX
sockets exist.
Without series: the sane sendmsg() needs to wait gc unreasonably.
If more than 16000 inflight AF_UNIX sockets exist and the garbage
collector is not running, unix_(dgram|stream)_sendmsg() call unix_gc().
Also, they wait for unix_gc() to complete.
In unix_gc(), all inflight AF_UNIX sockets are traversed at least once,
and more if they are the GC candidate. Thus, sendmsg() significantly
slows down with too many inflight AF_UNIX sockets.
There is a small window to invoke multiple unix_gc() instances, which
will then be blocked by the same spinlock except for one.
Let's convert unix_gc() to use struct work so that it will not consume
CPUs unnecessarily.
Note WRITE_ONCE(gc_in_progress, true) is moved before running GC.
If we leave the WRITE_ONCE() as is and use the following test to
call flush_work(), a process might not call it.
CPU 0 CPU 1
--- ---
start work and call __unix_gc()
if (work_pending(&unix_gc_work) || <-- false
READ_ONCE(gc_in_progress)) <-- false
flush_work(); <-- missed!
WRITE_ONCE(gc_in_progress, true)
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20240123170856.41348-5-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Leon Romanovsky <leon@kernel.org> Cc: David Ahern <dsahern@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Kees Cook <keescook@chromium.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Cc: Lennart Poettering <mzxreary@0pointer.de> Cc: Luca Boccassi <bluca@debian.org> Cc: linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org Cc: linux-arch@vger.kernel.org Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When we call btrfs_read_folio() to bring a folio uptodate, we unlock the
folio. The result of that is that a different thread can modify the
mapping (like remove it with invalidate) before we call folio_lock().
This results in an invalid page and we need to try again.
In particular, if we are relocating concurrently with aborting a
transaction, this can result in a crash like the following:
This occurs because cleanup_one_transaction() calls
destroy_delalloc_inodes() which calls invalidate_inode_pages2() which
takes the folio_lock before setting mapping to NULL. We fail to check
this, and subsequently call set_extent_mapping(), which assumes that
mapping != NULL (in fact it asserts that in debug mode)
Note that the "fixes" patch here is not the one that introduced the
race (the very first iteration of this code from 2009) but a more recent
change that made this particular crash happen in practice.
Fixes: e7f1326cc24e ("btrfs: set page extent mapped after read_folio in relocate_one_page") CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Zhaoyang Li <lizy04@hust.edu.cn> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
hrtimers are migrated away from the dying CPU to any online target at
the CPUHP_AP_HRTIMERS_DYING stage in order not to delay bandwidth timers
handling tasks involved in the CPU hotplug forward progress.
However wakeups can still be performed by the outgoing CPU after
CPUHP_AP_HRTIMERS_DYING. Those can result again in bandwidth timers being
armed. Depending on several considerations (crystal ball power management
based election, earliest timer already enqueued, timer migration enabled or
not), the target may eventually be the current CPU even if offline. If that
happens, the timer is eventually ignored.
The most notable example is RCU which had to deal with each and every of
those wake-ups by deferring them to an online CPU, along with related
workarounds:
_ e787644caf76 (rcu: Defer RCU kthreads wakeup when CPU is dying)
_ 9139f93209d1 (rcu/nocb: Fix RT throttling hrtimer armed from offline CPU)
_ f7345ccc62a4 (rcu/nocb: Fix rcuog wake-up from offline softirq)
The problem isn't confined to RCU though as the stop machine kthread
(which runs CPUHP_AP_HRTIMERS_DYING) reports its completion at the end
of its work through cpu_stop_signal_done() and performs a wake up that
eventually arms the deadline server timer:
Instead of providing yet another bandaid to work around the situation, fix
it in the hrtimers infrastructure instead: always migrate away a timer to
an online target whenever it is enqueued from an offline CPU.
This will also allow to revert all the above RCU disgraceful hacks.
Fixes: 5c0930ccaad5 ("hrtimers: Push pending hrtimers away from outgoing CPU earlier") Reported-by: Vlad Poenaru <vlad.wing@gmail.com> Reported-by: Usama Arif <usamaarif642@gmail.com> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Tested-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/all/20250117232433.24027-1-frederic@kernel.org Closes: 20241213203739.1519801-1-usamaarif642@gmail.com Signed-off-by: Zhaoyang Li <lizy04@hust.edu.cn> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The access to page pool `cache' array and the `count' variable
is not locked. Page pool cache access is fine as long as there
is only one consumer per pool.
octeontx2 driver fills in rx buffers from page pool in NAPI context.
If system is stressed and could not allocate buffers, refiiling work
will be delegated to a delayed workqueue. This means that there are
two cosumers to the page pool cache.
Either workqueue or IRQ/NAPI can be run on other CPU. This will lead
to lock less access, hence corruption of cache pool indexes.
To fix this issue, NAPI is rescheduled from workqueue context to refill
rx buffers.
Fixes: b2e3406a38f0 ("octeontx2-pf: Add support for page pool") Signed-off-by: Ratheesh Kannoth <rkannoth@marvell.com> Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
octeontx2 driver calls page_pool_create() during driver probe()
and fails if queue size > 32k. Page pool infra uses these buffers
as shock absorbers for burst traffic. These pages are pinned down
over time as working sets varies, due to the recycling nature
of page pool, given page pool (currently) don't have a shrinker
mechanism, the pages remain pinned down in ptr_ring.
Instead of clamping page_pool size to 32k at
most, limit it even more to 2k to avoid wasting memory.
This have been tested on octeontx2 CN10KA hardware.
TCP and UDP tests using iperf shows no performance regressions.
Fixes: b2e3406a38f0 ("octeontx2-pf: Add support for page pool") Suggested-by: Alexander Lobakin <aleksander.lobakin@intel.com> Reviewed-by: Sunil Goutham <sgoutham@marvell.com> Signed-off-by: Ratheesh Kannoth <rkannoth@marvell.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Smatch warns:
drivers/dma/idxd/cdev.c:327:
idxd_cdev_open() warn: 'sva' was already freed.
When idxd_wq_set_pasid() fails, the current code unbinds sva and then
goes to 'failed_set_pasid' where iommu_sva_unbind_device is called
again causing the above warning.
[ device_user_pasid_enabled(idxd) is still true when calling
failed_set_pasid ]
Fix this by removing additional unbind when idxd_wq_set_pasid() fails
Fixes: b022f59725f0 ("dmaengine: idxd: add idxd_copy_cr() to copy user completion record during page fault handling") Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Acked-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20230509060716.2830630-1-harshit.m.mogalapalli@oracle.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86/mm/init: Handle the special case of device private pages in add_pages(), to not increase max_pfn and trigger dma_addressing_limited() bounce buffers bounce buffers
As Bert Karwatzki reported, the following recent commit causes a
performance regression on AMD iGPU and dGPU systems:
7ffb791423c7 ("x86/kaslr: Reduce KASLR entropy on most x86 systems")
It exposed a bug with nokaslr and zone device interaction.
The root cause of the bug is that, the GPU driver registers a zone
device private memory region. When KASLR is disabled or the above commit
is applied, the direct_map_physmem_end is set to much higher than 10 TiB
typically to the 64TiB address. When zone device private memory is added
to the system via add_pages(), it bumps up the max_pfn to the same
value. This causes dma_addressing_limited() to return true, since the
device cannot address memory all the way up to max_pfn.
This caused a regression for games played on the iGPU, as it resulted in
the DMA32 zone being used for GPU allocations.
Fix this by not bumping up max_pfn on x86 systems, when pgmap is passed
into add_pages(). The presence of pgmap is used to determine if device
private memory is being added via add_pages().
More details:
devm_request_mem_region() and request_free_mem_region() request for
device private memory. iomem_resource is passed as the base resource
with start and end parameters. iomem_resource's end depends on several
factors, including the platform and virtualization. On x86 for example
on bare metal, this value is set to boot_cpu_data.x86_phys_bits.
boot_cpu_data.x86_phys_bits can change depending on support for MKTME.
By default it is set to the same as log2(direct_map_physmem_end) which
is 46 to 52 bits depending on the number of levels in the page table.
The allocation routines used iomem_resource's end and
direct_map_physmem_end to figure out where to allocate the region.
[ arch/powerpc is also impacted by this problem, but this patch does not fix
the issue for PowerPC. ]
Testing:
1. Tested on a virtual machine with test_hmm for zone device inseration
Clang is a little more pedantic than GCC, which does not warn when
falling through to a case that is just break or return. Clang's version
is more in line with the kernel's own stance in deprecated.rst, which
states that all switch/case blocks must end in either break,
fallthrough, continue, goto, or return. Add the missing break to silence
the warning.
On (H)SCIF with a Baud Rate Generator for External Clock (BRG), there
are multiple ways to configure the requested serial speed. If firmware
uses a different method than Linux, and if any debug info is printed
after the Bit Rate Register (SCBRR) is restored, but before termios is
reconfigured (which configures the alternative method), the system may
lock-up during resume.
Fix this by saving and restoring the contents of the BRG Frequency
Division (SCDL) and Clock Select (SCCKS) registers as well.
Also save and restore the HSCIF's Sampling Rate Register (HSSRR), which
configures the sampling point, and the SCIFA/SCIFB's Serial Port Control
and Data Registers (SCPCR/SCPDR), which configure the optional control
flow signals.
After this, all registers that are not saved/restored are either:
- read-only,
- write-only,
- status registers containing flags with clear-after-set semantics,
- FIFO Data Count Trigger registers, which do not matter much for
the serial console.
A new on by default warning in clang [1] aims to flags instances where
const variables without static or thread local storage or const members
in aggregate types are not initialized because it can lead to an
indeterminate value. This is quite noisy for the kernel due to
instances originating from header files such as:
drivers/gpu/drm/i915/gt/intel_ring.h:62:2: error: default initialization of an object of type 'typeof (ring->size)' (aka 'const unsigned int') leaves the object uninitialized [-Werror,-Wdefault-const-init-var-unsafe]
62 | typecheck(typeof(ring->size), next);
| ^
include/linux/typecheck.h:10:9: note: expanded from macro 'typecheck'
10 | ({ type __dummy; \
| ^
include/net/ip.h:478:14: error: default initialization of an object of type 'typeof (rt->dst.expires)' (aka 'const unsigned long') leaves the object uninitialized [-Werror,-Wdefault-const-init-var-unsafe]
478 | if (mtu && time_before(jiffies, rt->dst.expires))
| ^
include/linux/jiffies.h:138:26: note: expanded from macro 'time_before'
138 | #define time_before(a,b) time_after(b,a)
| ^
include/linux/jiffies.h:128:3: note: expanded from macro 'time_after'
128 | (typecheck(unsigned long, a) && \
| ^
include/linux/typecheck.h:11:12: note: expanded from macro 'typecheck'
11 | typeof(x) __dummy2; \
| ^
include/linux/list.h:409:27: warning: default initialization of an object of type 'union (unnamed union at include/linux/list.h:409:27)' with const member leaves the object uninitialized [-Wdefault-const-init-field-unsafe]
409 | struct list_head *next = smp_load_acquire(&head->next);
| ^
include/asm-generic/barrier.h:176:29: note: expanded from macro 'smp_load_acquire'
176 | #define smp_load_acquire(p) __smp_load_acquire(p)
| ^
arch/arm64/include/asm/barrier.h:164:59: note: expanded from macro '__smp_load_acquire'
164 | union { __unqual_scalar_typeof(*p) __val; char __c[1]; } __u; \
| ^
include/linux/list.h:409:27: note: member '__val' declared 'const' here
crypto/scatterwalk.c:66:22: error: default initialization of an object of type 'struct scatter_walk' with const member leaves the object uninitialized [-Werror,-Wdefault-const-init-field-unsafe]
66 | struct scatter_walk walk;
| ^
include/crypto/algapi.h:112:15: note: member 'addr' declared 'const' here
112 | void *const addr;
| ^
fs/hugetlbfs/inode.c:733:24: error: default initialization of an object of type 'struct vm_area_struct' with const member leaves the object uninitialized [-Werror,-Wdefault-const-init-field-unsafe]
733 | struct vm_area_struct pseudo_vma;
| ^
include/linux/mm_types.h:803:20: note: member 'vm_flags' declared 'const' here
803 | const vm_flags_t vm_flags;
| ^
Silencing the instances from typecheck.h is difficult because '= {}' is
not available in older but supported compilers and '= {0}' would cause
warnings about a literal 0 being treated as NULL. While it might be
possible to come up with a local hack to silence the warning for
clang-21+, it may not be worth it since -Wuninitialized will still
trigger if an uninitialized const variable is actually used.
In all audited cases of the "field" variant of the warning, the members
are either not used in the particular call path, modified through other
means such as memset() / memcpy() because the containing object is not
const, or are within a union with other non-const members.
Since this warning does not appear to have a high signal to noise ratio,
just disable it.
Cc: stable@vger.kernel.org Link: https://github.com/llvm/llvm-project/commit/576161cb6069e2c7656a8ef530727a0f4aefff30 Reported-by: Linux Kernel Functional Testing <lkft@linaro.org> Closes: https://lore.kernel.org/CA+G9fYuNjKcxFKS_MKPRuga32XbndkLGcY-PVuoSwzv6VWbY=w@mail.gmail.com/ Reported-by: Marcus Seyfarth <m.seyfarth@gmail.com> Closes: https://github.com/ClangBuiltLinux/linux/issues/2088 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
[nathan: Apply change to Makefile instead of scripts/Makefile.extrawarn
due to lack of e88ca24319e4 in older stable branches] Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If, in a previous transfer, the controller sends more data than expected
by the DSPI target, SR.RFDF (RX FIFO is not empty) will remain asserted.
When flushing the FIFOs at the beginning of a new transfer (writing 1
into MCR.CLR_TXF and MCR.CLR_RXF), SR.RFDF should also be cleared.
Otherwise, when running in target mode with DMA, if SR.RFDF remains
asserted, the DMA callback will be fired before the controller sends any
data.
Take this opportunity to reset all Status Register fields.
Fixes: 5ce3cc567471 ("spi: spi-fsl-dspi: Provide support for DSPI slave mode operation (Vybryd vf610)") Signed-off-by: Larisa Grigore <larisa.grigore@nxp.com> Signed-off-by: James Clark <james.clark@linaro.org> Link: https://patch.msgid.link/20250522-james-nxp-spi-v2-3-bea884630cfb@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The XSPI mode implementation in this driver still uses the EOQ flag to
signal the last word in a transmission and deassert the PCS signal.
However, at speeds lower than ~200kHZ, the PCS signal seems to remain
asserted even when SR[EOQF] = 1 indicates the end of a transmission.
This is a problem for target devices which require the deassertation of
the PCS signal between transfers.
Hence, this commit 'forces' the deassertation of the PCS by stopping the
module through MCR[HALT] after completing a new transfer. According to
the reference manual, the module stops or transitions from the Running
state to the Stopped state after the current frame, when any one of the
following conditions exist:
- The value of SR[EOQF] = 1.
- The chip is in Debug mode and the value of MCR[FRZ] = 1.
- The value of MCR[HALT] = 1.
This shouldn't be done if the last transfer in the message has cs_change
set.
Fixes: ea93ed4c181b ("spi: spi-fsl-dspi: Use EOQ for last word in buffer even for XSPI mode") Signed-off-by: Bogdan-Gabriel Roman <bogdan-gabriel.roman@nxp.com> Signed-off-by: Larisa Grigore <larisa.grigore@nxp.com> Signed-off-by: James Clark <james.clark@linaro.org> Link: https://patch.msgid.link/20250522-james-nxp-spi-v2-2-bea884630cfb@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
DSPI registers are NOT continuous, some registers are reserved and
accessing them from userspace will trigger external abort, add regmap
register access table to avoid below abort.
Fixes: 1acbdeb92c87 ("spi/fsl-dspi: Convert to use regmap and add big-endian support") Co-developed-by: Xulin Sun <xulin.sun@windriver.com> Signed-off-by: Xulin Sun <xulin.sun@windriver.com> Signed-off-by: Larisa Grigore <larisa.grigore@nxp.com> Signed-off-by: James Clark <james.clark@linaro.org> Link: https://patch.msgid.link/20250522-james-nxp-spi-v2-1-bea884630cfb@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
If there is no stream data in file, v_len is zero.
So, If position(*pos) is zero, stream write will fail
due to stream write position validation check.
This patch reorganize stream write position validation.
Fixes: 0ca6df4f40cf ("ksmbd: prevent out-of-bounds stream writes by validating *pos") Signed-off-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Hardware that uses I2C wasn't designed with high speeds in mind, so
communication with PMIC via RSB can intermittently fail. Go back to I2C
as higher speed and efficiency isn't worth the trouble.
__alloc_pages_slowpath has no change detection for ac->nodemask in the
part of retry path, while cpuset can modify it in parallel. For some
processes that set mempolicy as MPOL_BIND, this results ac->nodemask
changes, and then the should_reclaim_retry will judge based on the latest
nodemask and jump to retry, while the get_page_from_freelist only
traverses the zonelist from ac->preferred_zoneref, which selected by a
expired nodemask and may cause infinite retries in some cases
cpu 64:
__alloc_pages_slowpath {
/* ..... */
retry:
/* ac->nodemask = 0x1, ac->preferred->zone->nid = 1 */
if (alloc_flags & ALLOC_KSWAPD)
wake_all_kswapds(order, gfp_mask, ac);
/* cpu 1:
cpuset_write_resmask
update_nodemask
update_nodemasks_hier
update_tasks_nodemask
mpol_rebind_task
mpol_rebind_policy
mpol_rebind_nodemask
// mempolicy->nodes has been modified,
// which ac->nodemask point to
Simultaneously starting multiple cpuset01 from LTP can quickly reproduce
this issue on a multi node server when the maximum memory pressure is
reached and the swap is enabled
Link: https://lkml.kernel.org/r/20250416082405.20988-1-zhangtianyang@loongson.cn Fixes: c33d6c06f60f ("mm, page_alloc: avoid looking up the first zone in a zonelist twice") Signed-off-by: Tianyang Zhang <zhangtianyang@loongson.cn> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@suse.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Zi Yan <ziy@nvidia.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
I am seeing soft lockup on certain machine types when a cgroup OOMs. This
is happening because killing the process in certain machine might be very
slow, which causes the soft lockup and RCU stalls. This happens usually
when the cgroup has MANY processes and memory.oom.group is set.
Example I am seeing in real production:
[462012.244552] Memory cgroup out of memory: Killed process 3370438 (crosvm) ....
....
[462037.318059] Memory cgroup out of memory: Killed process 4171372 (adb) ....
[462037.348314] watchdog: BUG: soft lockup - CPU#64 stuck for 26s! [stat_manager-ag:1618982]
....
Quick look at why this is so slow, it seems to be related to serial flush
for certain machine types. For all the crashes I saw, the target CPU was
at console_flush_all().
In the case above, there are thousands of processes in the cgroup, and it
is soft locking up before it reaches the 1024 limit in the code (which
would call the cond_resched()). So, cond_resched() in 1024 blocks is not
sufficient.
Remove the counter-based conditional rescheduling logic and call
cond_resched() unconditionally after each task iteration, after fn() is
called. This avoids the lockup independently of how slow fn() is.
Link: https://lkml.kernel.org/r/20250523-memcg_fix-v1-1-ad3eafb60477@debian.org Fixes: ade81479c7dd ("memcg: fix soft lockup in the OOM process") Signed-off-by: Breno Leitao <leitao@debian.org> Suggested-by: Rik van Riel <riel@surriel.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Michael van der Westhuizen <rmikey@meta.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Pavel Begunkov <asml.silence@gmail.com> Cc: Chen Ridong <chenridong@huawei.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 68bfdc8dc0a1a ("drm/amd: Keep display off while going into S4")
attempted to keep displays off during the S4 sequence by not resuming
display IP. This however leads to hangs because DRM clients such as the
console can try to access registers and cause a hang.
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4155 Fixes: 68bfdc8dc0a1a ("drm/amd: Keep display off while going into S4") Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Link: https://lore.kernel.org/r/20250522141328.115095-1-mario.limonciello@amd.com Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit e485502c37b097b0bd773baa7e2741bf7bd2909a) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Multiple pointers in struct cifs_search_info (ntwrk_buf_start,
srch_entries_start, and last_entry) point to the same allocated buffer.
However, when freeing this buffer, only ntwrk_buf_start was set to NULL,
while the other pointers remained pointing to freed memory.
This is defensive programming to prevent potential issues with stale
pointers. While the active UAF vulnerability is fixed by the previous
patch, this change ensures consistent pointer state and more robust error
handling.
Signed-off-by: Wang Zhaolong <wangzhaolong1@huawei.com> Cc: stable@vger.kernel.org Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a race condition in the readdir concurrency process, which may
access the rsp buffer after it has been released, triggering the
following KASAN warning.
==================================================================
BUG: KASAN: slab-use-after-free in cifs_fill_dirent+0xb03/0xb60 [cifs]
Read of size 4 at addr ffff8880099b819c by task a.out/342975
The buggy address belongs to the object at ffff8880099b8000
which belongs to the cache cifs_request of size 16588
The buggy address is located 412 bytes inside of
freed 16588-byte region [ffff8880099b8000, ffff8880099bc0cc)
When DP connected to a device with HDR capability,
the hdr structure was filled.Then connected to another
sink device without hdr capability, but the hdr info
still exist.
Fixes: e85959d6cbe0 ("drm: Parse HDR metadata info from EDID") Cc: <stable@vger.kernel.org> # v5.3+ Signed-off-by: "feijuan.li" <feijuan.li@samsung.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Link: https://lore.kernel.org/r/20250514063511.4151780-1-feijuan.li@samsung.com Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the 'buf' array received from the user contains an empty string, the
'length' variable will be zero. Accessing the 'buf' array element with
index 'length - 1' will result in a buffer overflow.
Add a check for an empty string.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: e8a60aa7404b ("platform/x86: Introduce support for Systems Management Driver over WMI for Dell Systems") Cc: stable@vger.kernel.org Signed-off-by: Vladimir Moskovkin <Vladimir.Moskovkin@kaspersky.com> Link: https://lore.kernel.org/r/39973642a4f24295b4a8fad9109c5b08@kaspersky.com Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For SOCK_STREAM sockets, if user buffer size (len) is less
than skb size (skb->len), the remaining data from skb
will be lost after calling kfree_skb().
To fix this, move the statement for partial reading
above skb deletion.
Found by InfoTeCS on behalf of Linux Verification Center (linuxtesting.org)
Fixes: 30a584d944fb ("[LLX]: SOCK_DGRAM interface fixes") Cc: stable@vger.kernel.org Signed-off-by: Ilia Gavrilov <Ilia.Gavrilov@infotecs.ru> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The PCM OSS layer tries to clear the buffer with the silence data at
initialization (or reconfiguration) of a stream with the explicit call
of snd_pcm_format_set_silence() with runtime->dma_area. But this may
lead to a UAF because the accessed runtime->dma_area might be freed
concurrently, as it's performed outside the PCM ops.
For avoiding it, move the code into the PCM core and perform it inside
the buffer access lock, so that it won't be changed during the
operation.
When the procfs content is generated for a bcm_op which is in the process
to be removed the procfs output might show unreliable data (UAF).
As the removal of bcm_op's is already implemented with rcu handling this
patch adds the missing rcu_read_lock() and makes sure the list entries
are properly removed under rcu protection.
Fixes: f1b4e32aca08 ("can: bcm: use call_rcu() instead of costly synchronize_rcu()") Reported-by: Anderson Nascimento <anderson@allelesecurity.com> Suggested-by: Anderson Nascimento <anderson@allelesecurity.com> Tested-by: Anderson Nascimento <anderson@allelesecurity.com> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://patch.msgid.link/20250519125027.11900-2-socketcan@hartkopp.net Cc: stable@vger.kernel.org # >= 5.4 Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The CAN broadcast manager (CAN BCM) can send a sequence of CAN frames via
hrtimer. The content and also the length of the sequence can be changed
resp reduced at runtime where the 'currframe' counter is then set to zero.
Although this appeared to be a safe operation the updates of 'currframe'
can be triggered from user space and hrtimer context in bcm_can_tx().
Anderson Nascimento created a proof of concept that triggered a KASAN
slab-out-of-bounds read access which can be prevented with a spin_lock_bh.
At the rework of bcm_can_tx() the 'count' variable has been moved into
the protected section as this variable can be modified from both contexts
too.
Fixes: ffd980f976e7 ("[CAN]: Add broadcast manager (bcm) protocol") Reported-by: Anderson Nascimento <anderson@allelesecurity.com> Tested-by: Anderson Nascimento <anderson@allelesecurity.com> Reviewed-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://patch.msgid.link/20250519125027.11900-1-socketcan@hartkopp.net Cc: stable@vger.kernel.org Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Allows slcan to receive short messages (typically errors) from the serial
interface.
When error support was added to slcan protocol in b32ff4668544e1333b694fcc7812b2d7397b4d6a ("can: slcan: extend the protocol
with error info") the minimum valid message size changed from 5 (minimum
standard can frame tIII0) to 3 ("e1a" is a valid protocol message, it is
one of the examples given in the comments for slcan_bump_err() ), but the
check for minimum message length prodicating all decoding was not adjusted.
This makes short error messages discarded and error frames not being
generated.
This patch changes the minimum length to the new minimum (3 characters,
excluding terminator, is now a valid message).
Signed-off-by: Carlos Sanchez <carlossanchez@geotab.com> Fixes: b32ff4668544 ("can: slcan: extend the protocol with error info") Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://patch.msgid.link/20250520102305.1097494-1-carlossanchez@geotab.com Cc: stable@vger.kernel.org Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A recent patch that addressed a UAF introduced a reference count leak:
the parallel_data refcount is incremented unconditionally, regardless
of the return value of queue_work(). If the work item is already queued,
the incremented refcount is never decremented.
Fix this by checking the return value of queue_work() and decrementing
the refcount when necessary.
If accept(2) is called on socket type algif_hash with
MSG_MORE flag set and crypto_ahash_import fails,
sk2 is freed. However, it is also freed in af_alg_release,
leading to slab-use-after-free error.
Fixes: fe869cdb89c9 ("crypto: algif_hash - User-space interface for hash operations") Cc: <stable@vger.kernel.org> Signed-off-by: Ivan Pravdin <ipravdin.official@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current implementation maps the APR table using a fixed size,
which can lead to incorrect mapping when the number of PFs and VFs
varies.
This patch corrects the mapping by calculating the APR table
size dynamically based on the values configured in the
APR_LMT_CFG register, ensuring accurate representation
of APR entries in debugfs.
Syzbot reported a slab-use-after-free with the following call trace:
==================================================================
BUG: KASAN: slab-use-after-free in tipc_aead_encrypt_done+0x4bd/0x510 net/tipc/crypto.c:840
Read of size 8 at addr ffff88807a733000 by task kworker/1:0/25
After freed the tipc_crypto tx by delete namespace, tipc_aead_encrypt_done
may still visit it in cryptd_queue_worker workqueue.
I reproduce this issue by:
ip netns add ns1
ip link add veth1 type veth peer name veth2
ip link set veth1 netns ns1
ip netns exec ns1 tipc bearer enable media eth dev veth1
ip netns exec ns1 tipc node set key this_is_a_master_key master
ip netns exec ns1 tipc bearer disable media eth dev veth1
ip netns del ns1
The key of reproduction is that, simd_aead_encrypt is interrupted, leading
to crypto_simd_usable() return false. Thus, the cryptd_queue_worker is
triggered, and the tipc_crypto tx will be visited.
Page pool for each rx queue enhance rx side performance
by reclaiming buffers back to each queue specific pool. DMA
mapping is done only for first allocation of buffers.
As subsequent buffers allocation avoid DMA mapping,
it results in performance improvement.
Image | Performance
------------ | ------------
Vannila | 3Mpps
|
with this | 42Mpps
change |
---------------------------
When enqueuing the first packet to an HFSC class, hfsc_enqueue() calls the
child qdisc's peek() operation before incrementing sch->q.qlen and
sch->qstats.backlog. If the child qdisc uses qdisc_peek_dequeued(), this may
trigger an immediate dequeue and potential packet drop. In such cases,
qdisc_tree_reduce_backlog() is called, but the HFSC qdisc's qlen and backlog
have not yet been updated, leading to inconsistent queue accounting. This
can leave an empty HFSC class in the active list, causing further
consequences like use-after-free.
This patch fixes the bug by moving the increment of sch->q.qlen and
sch->qstats.backlog before the call to the child qdisc's peek() operation.
This ensures that queue length and backlog are always accurate when packet
drops or dequeues are triggered during the peek.
Fixes: 12d0ad3be9c3 ("net/sched/sch_hfsc.c: handle corner cases where head may change invalidating calculated deadline") Reported-by: Mingi Cho <mincho@theori.io> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250518222038.58538-2-xiyou.wangcong@gmail.com Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Leaving the CQ critical section in the middle of a overflow flushing
can cause cqe reordering since the cache cq pointers are reset and any
new cqe emitters that might get called in between are not going to be
forced into io_cqe_cache_refill().
SGMII_CTRL register, which specifies the active interface, was not
properly restored when resuming from suspend. This led to incorrect
interface selection after resume particularly in scenarios involving
the FPGA.
To fix this:
- Move the SGMII_CTRL setup out of the probe function.
- Initialize the register in the hardware initialization helper function,
which is called during both device initialization and resume.
This ensures the interface configuration is consistently restored after
suspend/resume cycles.
Fixes: a46d9d37c4f4f ("net: lan743x: Add support for SGMII interface") Signed-off-by: Thangaraj Samynathan <thangaraj.s@microchip.com> Link: https://patch.msgid.link/20250516035719.117960-1-thangaraj.s@microchip.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
While the MDIO address of the internal PHY on Allwinner sun8i chips is
generally 1, of_mdio_parse_addr is used to cleanly parse the address
from the device-tree instead of hardcoding it.
A commit reworking the code ditched the parsed value and hardcoded the
value 1 instead, which didn't really break anything but is more fragile
and not future-proof.
Restore the initial behavior using the parsed address returned from the
helper.
The ice_vc_repr_add_mac() function indicates that it does not store the MAC
address filters in the firmware. However, it still increments vf->num_mac.
This is incorrect, as vf->num_mac should represent the number of MAC
filters currently programmed to firmware.
Indeed, we only perform this increment if the requested filter is a unicast
address that doesn't match the existing vf->hw_lan_addr. In addition,
ice_vc_repr_del_mac() does not decrement the vf->num_mac counter. This
results in the counter becoming out of sync with the actual count.
As it turns out, vf->num_mac is currently only used in legacy made without
port representors. The single place where the value is checked is for
enforcing a filter limit on untrusted VFs.
Upcoming patches to support VF Live Migration will use this value when
determining the size of the TLV for MAC address filters. Fix the
representor mode function to stop incrementing the counter incorrectly.
Fixes: ac19e03ef780 ("ice: allow process VF opcodes in different ways") Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com> Reviewed-by: Simon Horman <horms@kernel.org> Tested-by: Sujai Buvaneswaran <sujai.buvaneswaran@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
When netfilter defrag hooks are loaded (due to the presence of conntrack
rules, for example), fragmented packets entering the bridge will be
defragged by the bridge's pre-routing hook (br_nf_pre_routing() ->
ipv4_conntrack_defrag()).
Later on, in the bridge's post-routing hook, the defragged packet will
be fragmented again. If the size of the largest fragment is larger than
what the kernel has determined as the destination MTU (using
ip_skb_dst_mtu()), the defragged packet will be dropped.
Before commit ac6627a28dbf ("net: ipv4: Consolidate ipv4_mtu and
ip_dst_mtu_maybe_forward"), ip_skb_dst_mtu() would return dst_mtu() as
the destination MTU. Assuming the dst entry attached to the packet is
the bridge's fake rtable one, this would simply be the bridge's MTU (see
fake_mtu()).
However, after above mentioned commit, ip_skb_dst_mtu() ends up
returning the route's MTU stored in the dst entry's metrics. Ideally, in
case the dst entry is the bridge's fake rtable one, this should be the
bridge's MTU as the bridge takes care of updating this metric when its
MTU changes (see br_change_mtu()).
Unfortunately, the last operation is a no-op given the metrics attached
to the fake rtable entry are marked as read-only. Therefore,
ip_skb_dst_mtu() ends up returning 1500 (the initial MTU value) and
defragged packets are dropped during fragmentation when dealing with
large fragments and high MTU (e.g., 9k).
Fix by moving the fake rtable entry's metrics to be per-bridge (in a
similar fashion to the fake rtable entry itself) and marking them as
writable, thereby allowing MTU changes to be reflected.
l2cap_check_enc_key_size shall check the security level of the
l2cap_chan rather than the hci_conn since for incoming connection
request that may be different as hci_conn may already been
encrypted using a different security level.
Fixes: 522e9ed157e3 ("Bluetooth: l2cap: Check encryption key size on incoming connection") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
The fix to block access from different address space did not return a
correct value for ->poll() change. kernel test bot reported that a
return value of type __poll_t is expected rather than int. Fix to return
POLLNVAL to indicate invalid request.
Fixes: 8dfa57aabff6 ("dmaengine: idxd: Fix allowing write() from different address spaces") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202505081851.rwD7jVxg-lkp@intel.com/ Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20250508170548.2747425-1-dave.jiang@intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Prior to this patch, the mark is sanitized (applying the state's mask to
the state's value) only on inserts when checking if a conflicting XFRM
state or policy exists.
We discovered in Cilium that this same sanitization does not occur
in the hot-path __xfrm_state_lookup. In the hot-path, the sk_buff's mark
is simply compared to the state's value:
if ((mark & x->mark.m) != x->mark.v)
continue;
Therefore, users can define unsanitized marks (ex. 0xf42/0xf00) which will
never match any packet.
This commit updates __xfrm_state_insert and xfrm_policy_insert to store
the sanitized marks, thus removing this footgun.
This has the side effect of changing the ip output, as the
returned mark will have the mask applied to it when printed.
Fixes: 3d6acfa7641f ("xfrm: SA lookups with mark") Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com> Signed-off-by: Louis DeLosSantos <louis.delos.devel@gmail.com> Co-developed-by: Louis DeLosSantos <louis.delos.devel@gmail.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
The D1/R528/T113 SoCs have a hidden divider of 2 in the MMC mod clocks,
just as other recent SoCs. So far we did not describe that, which led
to the resulting MMC clock rate to be only half of its intended value.
Use a macro that allows to describe a fixed post-divider, to compensate
for that divisor.
This brings the MMC performance on those SoCs to its expected level,
so about 23 MB/s for SD cards, instead of the 11 MB/s measured so far.
Fixes: 35b97bb94111 ("clk: sunxi-ng: Add support for the D1 SoC clocks") Reported-by: Kuba Szczodrzyński <kuba@szczodrzynski.pl> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Link: https://patch.msgid.link/20250501120631.837186-1-andre.przywara@arm.com Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Recent change to handle platforms with only single power domain broke
pronto-v3 which requires power domains and doesn't have fallback voltage
regulators in case power domains are missing. Add a check to verify
the number of fallback voltage regulators before using the code which
handles single power domain situation.
Fixes: 65991ea8a6d1 ("remoteproc: qcom_wcnss: Handle platforms with only single power domain") Signed-off-by: Matti Lehtimäki <matti.lehtimaki@gmail.com> Tested-by: Luca Weiss <luca.weiss@fairphone.com> # sdm632-fairphone-fp3 Link: https://lore.kernel.org/r/20250511234026.94735-1-matti.lehtimaki@gmail.com Signed-off-by: Bjorn Andersson <andersson@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Define idxd_copy_cr() to copy completion record to fault address in
user address that is found by work queue (wq) and PASID.
It will be used to write the user's completion record that the hardware
device is not able to write due to user completion record page fault.
An xarray is added to associate the PASID and mm with the
struct idxd_user_context so mm can be found by PASID and wq.
It is called when handling the completion record fault in a kernel thread
context. Switch to the mm using kthread_use_vm() and copy the
completion record to the mm via copy_to_user(). Once the copy is
completed, switch back to the current mm using kthread_unuse_mm().
Suggested-by: Christoph Hellwig <hch@infradead.org> Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Suggested-by: Tony Luck <tony.luck@intel.com> Tested-by: Tony Zhu <tony.zhu@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20230407203143.2189681-9-fenghua.yu@intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
Stable-dep-of: 8dfa57aabff6 ("dmaengine: idxd: Fix allowing write() from different address spaces") Signed-off-by: Sasha Levin <sashal@kernel.org>
Add a workqueue for user submitted completion record fault processing.
The workqueue creation and destruction lifetime will be tied to the user
sub-driver since it will only be used when the wq is a user type.
Tested-by: Tony Zhu <tony.zhu@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Co-developed-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: https://lore.kernel.org/r/20230407203143.2189681-7-fenghua.yu@intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
Stable-dep-of: 8dfa57aabff6 ("dmaengine: idxd: Fix allowing write() from different address spaces") Signed-off-by: Sasha Levin <sashal@kernel.org>
The current scheme for caching the encap socket can lead to reference
leaks when we try to delete the netns.
The reference chain is: xfrm_state -> enacp_sk -> netns
Since the encap socket is a userspace socket, it holds a reference on
the netns. If we delete the espintcp state (through flush or
individual delete) before removing the netns, the reference on the
socket is dropped and the netns is correctly deleted. Otherwise, the
netns may not be reachable anymore (if all processes within the ns
have terminated), so we cannot delete the xfrm state to drop its
reference on the socket.
This patch results in a small (~2% in my tests) performance
regression.
A GC-type mechanism could be added for the socket cache, to clear
references if the state hasn't been used "recently", but it's a lot
more complex than just not caching the socket.
... or we risk stealing final mntput from sync umount - raising mnt_count
after umount(2) has verified that victim is not busy, but before it
has set MNT_SYNC_UMOUNT; in that case __legitimize_mnt() doesn't see
that it's safe to quietly undo mnt_count increment and leaves dropping
the reference to caller, where it'll be a full-blown mntput().
Check under mount_lock is needed; leaving the current one done before
taking that makes no sense - it's nowhere near common enough to bother
with.
Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
Make xenbus_init() allow a non-local xenstore for a PVH dom0 - it is
currently forced to XS_LOCAL. With Hyperlaunch booting dom0 and a
xenstore stubdom, dom0 can be handled as a regular XS_HVM following the
late init path.
Ideally we'd drop the use of xen_initial_domain() and just check for the
event channel instead. However, ARM has a xen,enhanced no-xenstore
mode, where the event channel and PFN would both be 0. Retain the
xen_initial_domain() check, and use that for an additional check when
the event channel is 0.
Check the full 64bit HVM_PARAM_STORE_EVTCHN value to catch the off
chance that high bits are set for the 32bit event channel.
btrfs_prelim_ref() calls the old and new reference variables in the
incorrect order. This causes a NULL pointer dereference because oldref
is passed as NULL to trace_btrfs_prelim_ref_insert().
Note, trace_btrfs_prelim_ref_insert() is being called with newref as
oldref (and oldref as NULL) on purpose in order to print out
the values of newref.
To reproduce:
echo 1 > /sys/kernel/debug/tracing/events/btrfs/btrfs_prelim_ref_insert/enable
syzbot complains about the cached sq head read, and it's totally right.
But we don't need to care, it's just reading fdinfo, and reading the
CQ or SQ tail/head entries are known racy in that they are just a view
into that very instant and may of course be outdated by the time they
are reported.
Annotate both the SQ head and CQ tail read with data_race() to avoid
this syzbot complaint.
queue->state_change is set as part of nvmet_tcp_set_queue_sock(), but if
the TCP connection isn't established when nvmet_tcp_set_queue_sock() is
called then queue->state_change isn't set and sock->sk->sk_state_change
isn't replaced.
As such we don't need to restore sock->sk->sk_state_change if
queue->state_change is NULL.
This avoids NULL pointer dereferences such as this:
HP Spectre x360 15-df1xxx with SSID 13c:863e requires similar
workarounds that were applied to another HP Spectre x360 models;
it has a mute LED only, no micmute LEDs, and needs the speaker GPIO
seup.
The public datasheets of the following Amlogic SoCs describe a typical
resistor value for the built-in pull up/down resistor:
- Meson8/8b/8m2: not documented
- GXBB (S905): 60 kOhm
- GXL (S905X): 60 kOhm
- GXM (S912): 60 kOhm
- G12B (S922X): 60 kOhm
- SM1 (S905D3): 60 kOhm
The public G12B and SM1 datasheets additionally state min and max
values:
- min value: 50 kOhm for both, pull-up and pull-down
- max value for the pull-up: 70 kOhm
- max value for the pull-down: 130 kOhm
Use 60 kOhm in the pinctrl-meson driver as well so it's shown in the
debugfs output. It may not be accurate for Meson8/8b/8m2 but in reality
60 kOhm is closer to the actual value than 1 Ohm.
Incorrect types are used as sizeof() arguments in devm_kcalloc().
It should be sizeof(dai_link_data) for link_data instead of
sizeof(snd_soc_dai_link).
We've been unable to locate a datasheet for this panel and our partner
has not been responsive, but all Starry eDP datasheets that we can
find agree on the same timing (delay_100_500_e200) so it should be
safe to use that here instead of the super conservative timings. We'll
still go a little extra conservative and allow `hpd_absent` of 200
instead of 100 because that won't add any real-world delay in most
cases.
We'll associate the string from the EDID ("116KHD024006") with this
panel. Given that the ID is the suspicious value of 0x0004 it seems
likely that Starry doesn't always update their IDs but the string will
still work to differentiate if we ever need to in the future.
msm is automagically upgrading normal commits to full modesets, and
that's a big no-no:
- for one this results in full on->off->on transitions on all these
crtc, at least if you're using the usual helpers. Which seems to be
the case, and is breaking uapi
- further even if the ctm change itself would not result in flicker,
this can hide modesets for other reasons. Which again breaks the
uapi
v2: I forgot the case of adding unrelated crtc state. Add that case
and link to the existing kerneldoc explainers. This has come up in an
irc discussion with Manasi and Ville about intel's bigjoiner mode.
Also cc everyone involved in the msm irc discussion, more people
joined after I sent out v1.
v3: Wording polish from Pekka and Thomas
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com> Acked-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: David Airlie <airlied@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Pekka Paalanen <pekka.paalanen@collabora.com> Cc: Rob Clark <robdclark@gmail.com> Cc: Simon Ser <contact@emersion.fr> Cc: Manasi Navare <navaremanasi@google.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Abhinav Kumar <quic_abhinavk@quicinc.com> Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Signed-off-by: Simona Vetter <simona.vetter@intel.com> Signed-off-by: Simona Vetter <simona.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20250108172417.160831-1-simona.vetter@ffwll.ch Signed-off-by: Sasha Levin <sashal@kernel.org>
When using nvmem, ath9k could potentially be loaded before nvmem, which
loads after mtd. This is an issue if DT contains an nvmem mac address.
If nvmem is not ready in time for ath9k, -EPROBE_DEFER is returned. Pass
it to _probe so that ath9k can properly grab a potentially present MAC
address.
Signed-off-by: Rosen Penev <rosenp@gmail.com> Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> Link: https://patch.msgid.link/20241105222326.194417-1-rosenp@gmail.com Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Previously, the ad5398 driver used only platform_data, which is
deprecated in favour of device tree. This caused the AD5398 to fail to
probe as it could not load its init_data. If the AD5398 has a device
tree node, pull the init_data from there using
of_get_regulator_init_data.
RXEMPTY can cause an IRQ, even though we may not do anything about it
(such as if we are waiting for more received data). We must still handle
these IRQs because we can tell they were caused by the device.
Some users want to plug two identical USB devices at the same time.
This static variable could theoretically cause them to use incorrect
TX power values.
Move the variable to the caller and pass a pointer to it to
rtw8822b_set_tx_power_index_by_rate().
Occasionally there is an EPROTO error during firmware download.
This error is converted to EAGAIN in the download function.
But nobody tries again and so device probe fails.
Implement download retry to fix this.
This error was observed (and fix tested) on a tbs2910 board [1]
with an embedded RTL8188EU (0bda:8179) device behind a USB hub.
IBS Op uses two counters: MaxCnt and CurCnt. MaxCnt is programmed with
the desired sample period. IBS hw generates sample when CurCnt reaches
to MaxCnt. The size of these counter used to be 20 bits but later they
were extended to 27 bits. The 7 bit extension is indicated by CPUID
Fn8000_001B_EAX[6 / OpCntExt].
perf_ibs->cnt_mask variable contains bit masks for MaxCnt and CurCnt.
But IBS driver does not set upper 7 bits of CurCnt in cnt_mask even
when OpCntExt CPUID bit is set. Fix this.
IBS driver uses cnt_mask[CurCnt] bits only while disabling an event.
Fortunately, CurCnt bits are not read from MSR while re-enabling the
event, instead MaxCnt is programmed with desired period and CurCnt is
set to 0. Hence, we did not see any issues so far.
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Namhyung Kim <namhyung@kernel.org> Link: https://lkml.kernel.org/r/20250115054438.1021-5-ravi.bangoria@amd.com Signed-off-by: Sasha Levin <sashal@kernel.org>
The `readlink(path, buf, sizeof(buf))` call reads at most sizeof(buf)
bytes and *does not* append null-terminator to buf. With respect to
that, fix two pieces in get_fd_type:
1. Change the truncation check to contain sizeof(buf) rather than
sizeof(path).
2. Append null-terminator to buf.
The ast driver looks up supplied display modes from an internal list of
display modes supported by the VBIOS.
Do not use the crtc_-prefixed display values from struct drm_display_mode
for looking up the VBIOS mode. The fields contain raw values that the
driver programs to hardware. They are affected by display settings like
double-scan or interlace.
Instead use the regular vdisplay and hdisplay fields for lookup. As the
programmed values can now differ from the values used for lookup, set
struct drm_display_mode.crtc_vdisplay and .crtc_hdisplay from the VBIOS
mode.
Some of the allowed operations put the tape into a known position to
continue operation assuming only the tape position has changed. But reset
sets partition, density and block size to drive default values. These
should be restored to the values before reset.
Normally the current block size and density are stored by the drive. If
the settings have been changed, the changed values have to be saved by the
driver across reset.
Signed-off-by: Kai Mäkisara <Kai.Makisara@kolumbus.fi> Link: https://lore.kernel.org/r/20250120194925.44432-2-Kai.Makisara@kolumbus.fi Reviewed-by: John Meneghini <jmeneghi@redhat.com> Tested-by: John Meneghini <jmeneghi@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
After a port swap between separate fabrics, there may be multiple nodes in
the vport's fc_nodes list with the same fabric well known address.
Duplication is temporary and eventually resolves itself after dev_loss_tmo
expires, but nameserver queries may still occur before dev_loss_tmo. This
possibly results in returning stale fabric ndlp objects. Fix by adding an
nlp_state check to ensure the ndlp search routine returns the correct newer
allocated ndlp fabric object.
projects / thirdparty / kernel / stable.git / log
