Building with -Werror showed another failure:
kernel/bpf/btf.c: In function 'btf_get_prog_ctx_type.isra.31':
kernel/bpf/btf.c:3508:63: error: array subscript 0 is above array bounds of 'u8[0]' {aka 'unsigned char[0]'} [-Werror=array-bounds]
ctx_type = btf_type_member(conv_struct) + bpf_ctx_convert_map[prog_type] * 2;
I don't actually understand why the array is empty, but a similar
fix has addressed a related problem, so I suppose we can do the
same thing here.
Fixes: ce27709b81 ("bpf: Fix build in minimal configurations")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191210203553.2941035-1-arnd@arndb.de
lockdep complains when padata's paths to update cpumasks via CPU hotplug
and sysfs are both taken:
# echo 0 > /sys/devices/system/cpu/cpu1/online
# echo ff > /sys/kernel/pcrypt/pencrypt/parallel_cpumask
======================================================
WARNING: possible circular locking dependency detected
5.4.0-rc8-padata-cpuhp-v3+ #1 Not tainted
------------------------------------------------------
bash/205 is trying to acquire lock:
ffffffff8286bcd0 (cpu_hotplug_lock.rw_sem){++++}, at: padata_set_cpumask+0x2b/0x120
but task is already holding lock:
ffff8880001abfa0 (&pinst->lock){+.+.}, at: padata_set_cpumask+0x26/0x120
which lock already depends on the new lock.
padata doesn't take cpu_hotplug_lock and pinst->lock in a consistent
order. Which should be first? CPU hotplug calls into padata with
cpu_hotplug_lock already held, so it should have priority.
Fixes: 6751fb3c0e ("padata: Use get_online_cpus/put_online_cpus")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Configuring an instance's parallel mask without any online CPUs...
echo 2 > /sys/kernel/pcrypt/pencrypt/parallel_cpumask
echo 0 > /sys/devices/system/cpu/cpu1/online
...makes tcrypt mode=215 crash like this:
divide error: 0000 [#1] SMP PTI
CPU: 4 PID: 283 Comm: modprobe Not tainted 5.4.0-rc8-padata-doc-v2+ #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191013_105130-anatol 04/01/2014
RIP: 0010:padata_do_parallel+0x114/0x300
Call Trace:
pcrypt_aead_encrypt+0xc0/0xd0 [pcrypt]
crypto_aead_encrypt+0x1f/0x30
do_mult_aead_op+0x4e/0xdf [tcrypt]
test_mb_aead_speed.constprop.0.cold+0x226/0x564 [tcrypt]
do_test+0x28c2/0x4d49 [tcrypt]
tcrypt_mod_init+0x55/0x1000 [tcrypt]
...
cpumask_weight() in padata_cpu_hash() returns 0 because the mask has no
CPUs. The problem is __padata_remove_cpu() checks for valid masks too
early and so doesn't mark the instance PADATA_INVALID as expected, which
would have made padata_do_parallel() return error before doing the
division.
Fix by introducing a second padata CPU hotplug state before
CPUHP_BRINGUP_CPU so that __padata_remove_cpu() sees the online mask
without @cpu. No need for the second argument to padata_replace() since
@cpu is now already missing from the online mask.
Fixes: 33e5445068 ("padata: Handle empty padata cpumasks")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If the pcrypt template is used multiple times in an algorithm, then a
deadlock occurs because all pcrypt instances share the same
padata_instance, which completes requests in the order submitted. That
is, the inner pcrypt request waits for the outer pcrypt request while
the outer request is already waiting for the inner.
This patch fixes this by allocating a set of queues for each pcrypt
instance instead of using two global queues. In order to maintain
the existing user-space interface, the pinst structure remains global
so any sysfs modifications will apply to every pcrypt instance.
Note that when an update occurs we have to allocate memory for
every pcrypt instance. Should one of the allocations fail we
will abort the update without rolling back changes already made.
The new per-instance data structure is called padata_shell and is
essentially a wrapper around parallel_data.
Reproducer:
#include <linux/if_alg.h>
#include <sys/socket.h>
#include <unistd.h>
int main()
{
struct sockaddr_alg addr = {
.salg_type = "aead",
.salg_name = "pcrypt(pcrypt(rfc4106-gcm-aesni))"
};
int algfd, reqfd;
char buf[32] = { 0 };
algfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
bind(algfd, (void *)&addr, sizeof(addr));
setsockopt(algfd, SOL_ALG, ALG_SET_KEY, buf, 20);
reqfd = accept(algfd, 0, 0);
write(reqfd, buf, 32);
read(reqfd, buf, 16);
}
Reported-by: syzbot+56c7151cad94eec37c521f0e47d2eee53f9361c4@syzkaller.appspotmail.com
Fixes: 5068c7a883 ("crypto: pcrypt - Add pcrypt crypto parallelization wrapper")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The function padata_remove_cpu was supposed to have been removed
along with padata_add_cpu but somehow it remained behind. Let's
kill it now as it doesn't even have a prototype anymore.
Fixes: 815613da6a ("kernel/padata.c: removed unused code")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The function padata_flush_queues is fundamentally broken because
it cannot force padata users to complete the request that is
underway. IOW padata has to passively wait for the completion
of any outstanding work.
As it stands flushing is used in two places. Its use in padata_stop
is simply unnecessary because nothing depends on the queues to
be flushed afterwards.
The other use in padata_replace is more substantial as we depend
on it to free the old pd structure. This patch instead uses the
pd->refcnt to dynamically free the pd structure once all requests
are complete.
Fixes: 2b73b07ab8 ("padata: Flush the padata queues actively")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This ended up causing some noise in places such as rxrpc running in softirq.
The warning is misleading in this case as the mutex trylock and unlock
operations are done within the same context; and therefore we need not
worry about the PI-boosting issues that comes along with no single-owner
lock guarantees.
While we don't want to support this in mutexes, there is no way out of
this yet; so lets get rid of the WARNs for now, as it is only fair to
code that has historically relied on non-preemptible softirq guarantees.
In addition, changing the lock type is also unviable: exclusive rwsems
have the same issue (just not the WARN_ON) and counting semaphores
would introduce a performance hit as mutexes are a lot more optimized.
This reverts:
a0855d24fc: ("locking/mutex: Complain upon mutex API misuse in IRQ contexts")
Fixes: a0855d24fc: ("locking/mutex: Complain upon mutex API misuse in IRQ contexts")
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Tested-by: David Howells <dhowells@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-afs@lists.infradead.org
Cc: linux-fsdevel@vger.kernel.org
Cc: will@kernel.org
Link: https://lkml.kernel.org/r/20191210220523.28540-1-dave@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Depending on type of BPF programs served by BPF trampoline it can call original
function. In such case the trampoline will skip one stack frame while
returning. That will confuse function_graph tracer and will cause crashes with
bad RIP. Teach graph tracer to skip functions that have BPF trampoline attached.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When pulling in Divya Indi's patch, I made a minor fix to remove unneeded
braces. I commited my fix up via "git commit -a --amend". Unfortunately, I
didn't realize I had some changes I was testing in the module code, and
those changes were applied to Divya's patch as well.
This reverts the accidental updates to the module code.
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Divya Indi <divya.indi@oracle.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Fixes: e585e6469d ("tracing: Verify if trace array exists before destroying it.")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit switches from static structure to dynamic allocation
for rcu_fwds as another step towards providing multiple call_rcu()
forward-progress kthreads.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit threads pointers to rcu_fwd structures through the remaining
functions using rcu_fwds directly, namely rcu_torture_fwd_prog_cbfree(),
rcutorture_oom_notify() and rcu_torture_fwd_prog_init().
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In order to add multiple call_rcu() forward-progress kthreads, it will
be necessary to dynamically allocate and initialize. This commit
therefore moves the initialization from compile time to instead
immediately precede thread-creation time.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In order to add multiple kthreads, it will be necessary to allow
the various functions to operate on a pointer to their kthread's
rcu_fwd structure. This commit therefore starts the process of
adding the needed "struct rcu_fwd" parameters and arguments to the
various callback forward-progress functions.
Note that rcutorture_oom_notify() and rcu_torture_fwd_cb_hist() will
eventually need to iterate over all kthreads' rcu_fwd structures.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Now that RCU behaves reasonably well with the current single-kthread
call_rcu() forward-progress testing, it is time to add more kthreads.
This commit takes a first step towards that goal by wrapping what
will be the per-kthread data into a new rcu_fwd structure.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently PREEMPT_RCU and TREE_RCU are mutually exclusive Kconfig
options. But PREEMPT_RCU actually specifies a kind of TREE_RCU,
namely a preemptible TREE_RCU. This commit therefore makes PREEMPT_RCU
be a modifer to the TREE_RCU Kconfig option. This has the benefit of
simplifying several of the #if expressions that formerly needed to
check both, but now need only check one or the other.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_preempt_check_blocked_tasks() function has a comment
that states that the rcu_node structure's ->lock must be held,
which might be informative, but which carries little weight if
not read. This commit therefore removes this comment in favor of
raw_lockdep_assert_held_rcu_node(), which will complain quite
visibly if the required lock is not held.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_gp_fqs_check_wake() function uses rcu_preempt_blocked_readers_cgp()
to read ->gp_tasks while other cpus might overwrite this field.
We need READ_ONCE()/WRITE_ONCE() pairs to avoid compiler
tricks and KCSAN splats like the following :
BUG: KCSAN: data-race in rcu_gp_fqs_check_wake / rcu_preempt_deferred_qs_irqrestore
write to 0xffffffff85a7f190 of 8 bytes by task 7317 on cpu 0:
rcu_preempt_deferred_qs_irqrestore+0x43d/0x580 kernel/rcu/tree_plugin.h:507
rcu_read_unlock_special+0xec/0x370 kernel/rcu/tree_plugin.h:659
__rcu_read_unlock+0xcf/0xe0 kernel/rcu/tree_plugin.h:394
rcu_read_unlock include/linux/rcupdate.h:645 [inline]
__ip_queue_xmit+0x3b0/0xa40 net/ipv4/ip_output.c:533
ip_queue_xmit+0x45/0x60 include/net/ip.h:236
__tcp_transmit_skb+0xdeb/0x1cd0 net/ipv4/tcp_output.c:1158
__tcp_send_ack+0x246/0x300 net/ipv4/tcp_output.c:3685
tcp_send_ack+0x34/0x40 net/ipv4/tcp_output.c:3691
tcp_cleanup_rbuf+0x130/0x360 net/ipv4/tcp.c:1575
tcp_recvmsg+0x633/0x1a30 net/ipv4/tcp.c:2179
inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838
sock_recvmsg_nosec net/socket.c:871 [inline]
sock_recvmsg net/socket.c:889 [inline]
sock_recvmsg+0x92/0xb0 net/socket.c:885
sock_read_iter+0x15f/0x1e0 net/socket.c:967
call_read_iter include/linux/fs.h:1864 [inline]
new_sync_read+0x389/0x4f0 fs/read_write.c:414
read to 0xffffffff85a7f190 of 8 bytes by task 10 on cpu 1:
rcu_gp_fqs_check_wake kernel/rcu/tree.c:1556 [inline]
rcu_gp_fqs_check_wake+0x93/0xd0 kernel/rcu/tree.c:1546
rcu_gp_fqs_loop+0x36c/0x580 kernel/rcu/tree.c:1611
rcu_gp_kthread+0x143/0x220 kernel/rcu/tree.c:1768
kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 10 Comm: rcu_preempt Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
[ paulmck: Added another READ_ONCE() for RCU CPU stall warnings. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Commit 18cd8c93e6 ("rcu/nocb: Print gp/cb kthread hierarchy if
dump_tree") added print statements to rcu_organize_nocb_kthreads for
debugging, but incorrectly guarded them, causing the function to always
spew out its message.
This patch fixes it by guarding both pr_alert statements with dump_tree,
while also changing the second pr_alert to a pr_cont, to print the
hierarchy in a single line (assuming that's how it was supposed to
work).
Fixes: 18cd8c93e6 ("rcu/nocb: Print gp/cb kthread hierarchy if dump_tree")
Signed-off-by: Stefan Reiter <stefan@pimaker.at>
[ paulmck: Make single-nocbs-CPU GP kthreads look less erroneous. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
An expedited grace period can be stalled by a nohz_full CPU looping
in kernel context. This possibility is currently handled by some
carefully crafted checks in rcu_read_unlock_special() that enlist help
from ksoftirqd when permitted by the scheduler. However, it is exactly
these checks that require the scheduler avoid holding any of its rq or
pi locks across rcu_read_unlock() without also having held them across
the entire RCU read-side critical section.
It would therefore be very nice if expedited grace periods could
handle nohz_full CPUs looping in kernel context without such checks.
This commit therefore adds code to the expedited grace period's wait
and cleanup code that forces the scheduler-clock interrupt on for CPUs
that fail to quickly supply a quiescent state. "Quickly" is currently
a hard-coded single-jiffy delay.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
After RCU flavor consolidation, synchronize_sched_expedited_wait() does
both RCU-preempt and RCU-sched, whichever happens to have been built into
the running kernel. This commit therefore changes this function's name
to synchronize_rcu_expedited_wait() to reflect its new generic nature.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The function-header comments in kernel/rcu/tree_exp.h have gotten a bit
out of date, so this commit updates a number of them.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Now that the RCU flavors have been consolidated, there is one common
function for checking to see if an expedited RCU grace period has
completed, namely sync_rcu_preempt_exp_done(). Because this function is
no longer specific to RCU-preempt, this commit removes the "_preempt" from
its name. This commit also changes sync_rcu_preempt_exp_done_unlocked()
to sync_rcu_exp_done_unlocked() for the same reason.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The current expedited RCU grace-period code expects that a task
requesting an expedited grace period cannot awaken until that grace
period has reached the wakeup phase. However, it is possible for a long
preemption to result in the waiting task never sleeping. For example,
consider the following sequence of events:
1. Task A starts an expedited grace period by invoking
synchronize_rcu_expedited(). It proceeds normally up to the
wait_event() near the end of that function, and is then preempted
(or interrupted or whatever).
2. The expedited grace period completes, and a kworker task starts
the awaken phase, having incremented the counter and acquired
the rcu_state structure's .exp_wake_mutex. This kworker task
is then preempted or interrupted or whatever.
3. Task A resumes and enters wait_event(), which notes that the
expedited grace period has completed, and thus doesn't sleep.
4. Task B starts an expedited grace period exactly as did Task A,
complete with the preemption (or whatever delay) just before
the call to wait_event().
5. The expedited grace period completes, and another kworker
task starts the awaken phase, having incremented the counter.
However, it blocks when attempting to acquire the rcu_state
structure's .exp_wake_mutex because step 2's kworker task has
not yet released it.
6. Steps 4 and 5 repeat, resulting in overflow of the rcu_node
structure's ->exp_wq[] array.
In theory, this is harmless. Tasks waiting on the various ->exp_wq[]
array will just be spuriously awakened, but they will just sleep again
on noting that the rcu_state structure's ->expedited_sequence value has
not advanced far enough.
In practice, this wastes CPU time and is an accident waiting to happen.
This commit therefore moves the rcu_exp_gp_seq_end() call that officially
ends the expedited grace period (along with associate tracing) until
after the ->exp_wake_mutex has been acquired. This prevents Task A from
awakening prematurely, thus preventing more than one expedited grace
period from being in flight during a previous expedited grace period's
wakeup phase.
Fixes: 3b5f668e71 ("rcu: Overlap wakeups with next expedited grace period")
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
[ paulmck: Added updated comment. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Tasks waiting within exp_funnel_lock() for an expedited grace period to
elapse can be starved due to the following sequence of events:
1. Tasks A and B both attempt to start an expedited grace
period at about the same time. This grace period will have
completed when the lower four bits of the rcu_state structure's
->expedited_sequence field are 0b'0100', for example, when the
initial value of this counter is zero. Task A wins, and thus
does the actual work of starting the grace period, including
acquiring the rcu_state structure's .exp_mutex and sets the
counter to 0b'0001'.
2. Because task B lost the race to start the grace period, it
waits on ->expedited_sequence to reach 0b'0100' inside of
exp_funnel_lock(). This task therefore blocks on the rcu_node
structure's ->exp_wq[1] field, keeping in mind that the
end-of-grace-period value of ->expedited_sequence (0b'0100')
is shifted down two bits before indexing the ->exp_wq[] field.
3. Task C attempts to start another expedited grace period,
but blocks on ->exp_mutex, which is still held by Task A.
4. The aforementioned expedited grace period completes, so that
->expedited_sequence now has the value 0b'0100'. A kworker task
therefore acquires the rcu_state structure's ->exp_wake_mutex
and starts awakening any tasks waiting for this grace period.
5. One of the first tasks awakened happens to be Task A. Task A
therefore releases the rcu_state structure's ->exp_mutex,
which allows Task C to start the next expedited grace period,
which causes the lower four bits of the rcu_state structure's
->expedited_sequence field to become 0b'0101'.
6. Task C's expedited grace period completes, so that the lower four
bits of the rcu_state structure's ->expedited_sequence field now
become 0b'1000'.
7. The kworker task from step 4 above continues its wakeups.
Unfortunately, the wake_up_all() refetches the rcu_state
structure's .expedited_sequence field:
wake_up_all(&rnp->exp_wq[rcu_seq_ctr(rcu_state.expedited_sequence) & 0x3]);
This results in the wakeup being applied to the rcu_node
structure's ->exp_wq[2] field, which is unfortunate given that
Task B is instead waiting on ->exp_wq[1].
On a busy system, no harm is done (or at least no permanent harm is done).
Some later expedited grace period will redo the wakeup. But on a quiet
system, such as many embedded systems, it might be a good long time before
there was another expedited grace period. On such embedded systems,
this situation could therefore result in a system hang.
This issue manifested as DPM device timeout during suspend (which
usually qualifies as a quiet time) due to a SCSI device being stuck in
_synchronize_rcu_expedited(), with the following stack trace:
schedule()
synchronize_rcu_expedited()
synchronize_rcu()
scsi_device_quiesce()
scsi_bus_suspend()
dpm_run_callback()
__device_suspend()
This commit therefore prevents such delays, timeouts, and hangs by
making rcu_exp_wait_wake() use its "s" argument consistently instead of
refetching from rcu_state.expedited_sequence.
Fixes: 3b5f668e71 ("rcu: Overlap wakeups with next expedited grace period")
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The code in sync_rcu_exp_select_node_cpus() calculates the current
CPU's mask within its rcu_node structure's bitmasks, but this has
already been computed in the ->grpmask field of that CPU's rcu_data
structure. This commit therefore just uses this ->grpmask field.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This fixes a data-race where `atomic_t dynticks` is copied by value. The
copy is performed non-atomically, resulting in a data-race if `dynticks`
is updated concurrently.
This data-race was found with KCSAN:
==================================================================
BUG: KCSAN: data-race in dyntick_save_progress_counter / rcu_irq_enter
write to 0xffff989dbdbe98e0 of 4 bytes by task 10 on cpu 3:
atomic_add_return include/asm-generic/atomic-instrumented.h:78 [inline]
rcu_dynticks_snap kernel/rcu/tree.c:310 [inline]
dyntick_save_progress_counter+0x43/0x1b0 kernel/rcu/tree.c:984
force_qs_rnp+0x183/0x200 kernel/rcu/tree.c:2286
rcu_gp_fqs kernel/rcu/tree.c:1601 [inline]
rcu_gp_fqs_loop+0x71/0x880 kernel/rcu/tree.c:1653
rcu_gp_kthread+0x22c/0x3b0 kernel/rcu/tree.c:1799
kthread+0x1b5/0x200 kernel/kthread.c:255
<snip>
read to 0xffff989dbdbe98e0 of 4 bytes by task 154 on cpu 7:
rcu_nmi_enter_common kernel/rcu/tree.c:828 [inline]
rcu_irq_enter+0xda/0x240 kernel/rcu/tree.c:870
irq_enter+0x5/0x50 kernel/softirq.c:347
<snip>
Reported by Kernel Concurrency Sanitizer on:
CPU: 7 PID: 154 Comm: kworker/7:1H Not tainted 5.3.0+ #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Workqueue: kblockd blk_mq_run_work_fn
==================================================================
Signed-off-by: Marco Elver <elver@google.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: rcu@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The "mask_ofl_ipi" is used to track which CPUs get IPIed, however
in the IPI sending loop, "mask_ofl_ipi" along with another variable
"mask_ofl_test" might also get modified to record which CPUs' quiesent
states must be reported by the sync_rcu_exp_select_node_cpus() at
the end of sync_rcu_exp_select_node_cpus(). This overlap of roles
can be confusing, so this patch cleans things a little by using
"mask_ofl_ipi" solely for determining which CPUs must be IPIed and
"mask_ofl_test" for solely determining on behalf of which CPUs
sync_rcu_exp_select_node_cpus() must report a quiscent state.
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Acked-by: Marco Elver <elver@google.com>
Add __rcu annotation to RCU-protected global pointer auditd_conn.
auditd_conn is an RCU-protected global pointer,i.e., accessed
via RCU methods rcu_dereference() and rcu_assign_pointer(),
hence it must be annotated with __rcu for sparse to report
warnings/errors correctly.
Fix multiple instances of the sparse error:
error: incompatible types in comparison expression
(different address spaces)
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Amol Grover <frextrite@gmail.com>
[PM: tweak subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Pull pr_warning() removal from Petr Mladek.
- Final removal of the unused pr_warning() alias.
You're supposed to use just "pr_warn()" in the kernel.
* tag 'printk-for-5.5-pr-warning-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
checkpatch: Drop pr_warning check
printk: Drop pr_warning definition
Fix up for "printk: Drop pr_warning definition"
workqueue: Use pr_warn instead of pr_warning
Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except
at places where these are defined. Later patches will remove the unused
definition of FIELD_SIZEOF().
This patch is generated using following script:
EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h"
git grep -l -e "\bFIELD_SIZEOF\b" | while read file;
do
if [[ "$file" =~ $EXCLUDE_FILES ]]; then
continue
fi
sed -i -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file;
done
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: David Miller <davem@davemloft.net> # for net
While running kprobe module test, find_module_all() caused
a suspicious RCU usage warning.
-----
=============================
WARNING: suspicious RCU usage
5.4.0-next-20191202+ #63 Not tainted
-----------------------------
kernel/module.c:619 RCU-list traversed in non-reader section!!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
1 lock held by rmmod/642:
#0: ffffffff8227da80 (module_mutex){+.+.}, at: __x64_sys_delete_module+0x9a/0x230
stack backtrace:
CPU: 0 PID: 642 Comm: rmmod Not tainted 5.4.0-next-20191202+ #63
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack+0x71/0xa0
find_module_all+0xc1/0xd0
__x64_sys_delete_module+0xac/0x230
? do_syscall_64+0x12/0x1f0
do_syscall_64+0x50/0x1f0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4b6d49
-----
This is because list_for_each_entry_rcu(modules) is called
without rcu_read_lock(). This is safe because the module_mutex
is locked.
Pass lockdep_is_held(&module_mutex) to the list_for_each_entry_rcu()
to suppress this warning, This also fixes similar issue in
mod_find() and each_symbol_section().
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
ns_get_path() and ns_get_path_cb() only ever return either NULL or an
ERR_PTR. It is far more idiomatic to simply return an integer, and it
makes all of the callers of ns_get_path() more straightforward to read.
Fixes: e149ed2b80 ("take the targets of /proc/*/ns/* symlinks to separate fs")
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull networking fixes from David Miller:
1) More jumbo frame fixes in r8169, from Heiner Kallweit.
2) Fix bpf build in minimal configuration, from Alexei Starovoitov.
3) Use after free in slcan driver, from Jouni Hogander.
4) Flower classifier port ranges don't work properly in the HW offload
case, from Yoshiki Komachi.
5) Use after free in hns3_nic_maybe_stop_tx(), from Yunsheng Lin.
6) Out of bounds access in mqprio_dump(), from Vladyslav Tarasiuk.
7) Fix flow dissection in dsa TX path, from Alexander Lobakin.
8) Stale syncookie timestampe fixes from Guillaume Nault.
[ Did an evil merge to silence a warning introduced by this pull - Linus ]
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (84 commits)
r8169: fix rtl_hw_jumbo_disable for RTL8168evl
net_sched: validate TCA_KIND attribute in tc_chain_tmplt_add()
r8169: add missing RX enabling for WoL on RTL8125
vhost/vsock: accept only packets with the right dst_cid
net: phy: dp83867: fix hfs boot in rgmii mode
net: ethernet: ti: cpsw: fix extra rx interrupt
inet: protect against too small mtu values.
gre: refetch erspan header from skb->data after pskb_may_pull()
pppoe: remove redundant BUG_ON() check in pppoe_pernet
tcp: Protect accesses to .ts_recent_stamp with {READ,WRITE}_ONCE()
tcp: tighten acceptance of ACKs not matching a child socket
tcp: fix rejected syncookies due to stale timestamps
lpc_eth: kernel BUG on remove
tcp: md5: fix potential overestimation of TCP option space
net: sched: allow indirect blocks to bind to clsact in TC
net: core: rename indirect block ingress cb function
net-sysfs: Call dev_hold always in netdev_queue_add_kobject
net: dsa: fix flow dissection on Tx path
net/tls: Fix return values to avoid ENOTSUPP
net: avoid an indirect call in ____sys_recvmsg()
...
Pull modules updates from Jessica Yu:
"Summary of modules changes for the 5.5 merge window:
- Refactor include/linux/export.h and remove code duplication between
EXPORT_SYMBOL and EXPORT_SYMBOL_NS to make it more readable.
The most notable change is that no namespace is represented by an
empty string "" rather than NULL.
- Fix a module load/unload race where waiter(s) trying to load the
same module weren't being woken up when a module finally goes away"
* tag 'modules-for-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
kernel/module.c: wakeup processes in module_wq on module unload
moduleparam: fix parameter description mismatch
export: avoid code duplication in include/linux/export.h
Pull thermal management updates from Zhang Rui:
- Fix a deadlock regression in thermal core framework, which was
introduced in 5.3 (Wei Wang)
- Initialize thermal control framework earlier to enable thermal
mitigation during boot (Amit Kucheria)
- Convert the Intelligent Power Allocator (IPA) thermal governor to
follow the generic PM_EM instead of its own Energy Model (Quentin
Perret)
- Introduce a new Amlogic soc thermal driver (Guillaume La Roque)
- Add interrupt support for tsens thermal driver (Amit Kucheria)
- Add support for MSM8956/8976 in tsens thermal driver
(AngeloGioacchino Del Regno)
- Add support for r8a774b1 in rcar thermal driver (Biju Das)
- Add support for Thermal Monitor Unit v2 in qoriq thermal driver
(Yuantian Tang)
- Some other fixes/cleanups on thermal core framework and soc thermal
drivers (Colin Ian King, Daniel Lezcano, Hsin-Yi Wang, Tian Tao)
* 'thermal/next' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux: (32 commits)
thermal: Fix deadlock in thermal thermal_zone_device_check
thermal: cpu_cooling: Migrate to using the EM framework
thermal: cpu_cooling: Make the power-related code depend on IPA
PM / EM: Declare EM data types unconditionally
arm64: defconfig: Enable CONFIG_ENERGY_MODEL
drivers: thermal: tsens: fix potential integer overflow on multiply
thermal: cpu_cooling: Reorder the header file
thermal: cpu_cooling: Remove pointless dependency on CONFIG_OF
thermal: no need to set .owner when using module_platform_driver
thermal: qcom: tsens-v1: Fix kfree of a non-pointer value
cpufreq: qcom-hw: Move driver initialization earlier
clk: qcom: Initialize clock drivers earlier
cpufreq: Initialize cpufreq-dt driver earlier
cpufreq: Initialize the governors in core_initcall
thermal: Initialize thermal subsystem earlier
thermal: Remove netlink support
dt: thermal: tsens: Document compatible for MSM8976/56
thermal: qcom: tsens-v1: Add support for MSM8956 and MSM8976
MAINTAINERS: add entry for Amlogic Thermal driver
thermal: amlogic: Add thermal driver to support G12 SoCs
...
Merge more updates from Andrew Morton:
"Most of the rest of MM and various other things. Some Kconfig rework
still awaits merges of dependent trees from linux-next.
Subsystems affected by this patch series: mm/hotfixes, mm/memcg,
mm/vmstat, mm/thp, procfs, sysctl, misc, notifiers, core-kernel,
bitops, lib, checkpatch, epoll, binfmt, init, rapidio, uaccess, kcov,
ubsan, ipc, bitmap, mm/pagemap"
* akpm: (86 commits)
mm: remove __ARCH_HAS_4LEVEL_HACK and include/asm-generic/4level-fixup.h
um: add support for folded p4d page tables
um: remove unused pxx_offset_proc() and addr_pte() functions
sparc32: use pgtable-nopud instead of 4level-fixup
parisc/hugetlb: use pgtable-nopXd instead of 4level-fixup
parisc: use pgtable-nopXd instead of 4level-fixup
nds32: use pgtable-nopmd instead of 4level-fixup
microblaze: use pgtable-nopmd instead of 4level-fixup
m68k: mm: use pgtable-nopXd instead of 4level-fixup
m68k: nommu: use pgtable-nopud instead of 4level-fixup
c6x: use pgtable-nopud instead of 4level-fixup
arm: nommu: use pgtable-nopud instead of 4level-fixup
alpha: use pgtable-nopud instead of 4level-fixup
gpio: pca953x: tighten up indentation
gpio: pca953x: convert to use bitmap API
gpio: pca953x: use input from regs structure in pca953x_irq_pending()
gpio: pca953x: remove redundant variable and check in IRQ handler
lib/bitmap: introduce bitmap_replace() helper
lib/test_bitmap: fix comment about this file
lib/test_bitmap: move exp1 and exp2 upper for others to use
...
For jited bpf program, if the subprogram count is 1, i.e.,
there is no callees in the program, prog->aux->func will be NULL
and prog->bpf_func points to image address of the program.
If there is more than one subprogram, prog->aux->func is populated,
and subprogram 0 can be accessed through either prog->bpf_func or
prog->aux->func[0]. Other subprograms should be accessed through
prog->aux->func[subprog_id].
This patch fixed a bug in check_attach_btf_id(), where
prog->aux->func[subprog_id] is used to access any subprogram which
caused a segfault like below:
[79162.619208] BUG: kernel NULL pointer dereference, address:
0000000000000000
......
[79162.634255] Call Trace:
[79162.634974] ? _cond_resched+0x15/0x30
[79162.635686] ? kmem_cache_alloc_trace+0x162/0x220
[79162.636398] ? selinux_bpf_prog_alloc+0x1f/0x60
[79162.637111] bpf_prog_load+0x3de/0x690
[79162.637809] __do_sys_bpf+0x105/0x1740
[79162.638488] do_syscall_64+0x5b/0x180
[79162.639147] entry_SYSCALL_64_after_hwframe+0x44/0xa9
......
Fixes: 5b92a28aae ("bpf: Support attaching tracing BPF program to other BPF programs")
Reported-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191205010606.177774-1-yhs@fb.com
