There is a matching of_node_put() in __of_detach_node_sysfs()
Remove misleading comment from function header comment for
of_detach_node().
This patch may result in memory leaks from code that directly calls
the dynamic node add and delete functions directly instead of
using changesets.
This commit should result in powerpc systems that dynamically
allocate a node, then later deallocate the node to have a
memory leak when the node is deallocated.
The next commit will fix the leak.
Tested-by: Alan Tull <atull@kernel.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
The refcount of a newly added overlay node decrements to one
(instead of zero) when the overlay changeset is destroyed. This
change will cause the final decrement be to zero.
After applying this patch, new validation warnings will be
reported from the devicetree unittest during boot due to
a pre-existing devicetree bug. The warnings will be similar to:
OF: ERROR: memory leak before free overlay changeset, /testcase-data/overlay-node/test-bus/test-unittest4
This pre-existing devicetree bug will also trigger a WARN_ONCE() from
refcount_sub_and_test_checked() when an overlay changeset is
destroyed without having first been applied. This scenario occurs
when an error in the overlay is detected during the overlay changeset
creation:
WARNING: CPU: 0 PID: 1 at lib/refcount.c:187 refcount_sub_and_test_checked+0xa8/0xbc
refcount_t: underflow; use-after-free.
(unwind_backtrace) from (show_stack+0x10/0x14)
(show_stack) from (dump_stack+0x6c/0x8c)
(dump_stack) from (__warn+0xdc/0x104)
(__warn) from (warn_slowpath_fmt+0x44/0x6c)
(warn_slowpath_fmt) from (refcount_sub_and_test_checked+0xa8/0xbc)
(refcount_sub_and_test_checked) from (kobject_put+0x24/0x208)
(kobject_put) from (of_changeset_destroy+0x2c/0xb4)
(of_changeset_destroy) from (free_overlay_changeset+0x1c/0x9c)
(free_overlay_changeset) from (of_overlay_remove+0x284/0x2cc)
(of_overlay_remove) from (of_unittest_apply_revert_overlay_check.constprop.4+0xf8/0x1e8)
(of_unittest_apply_revert_overlay_check.constprop.4) from (of_unittest_overlay+0x960/0xed8)
(of_unittest_overlay) from (of_unittest+0x1cc4/0x2138)
(of_unittest) from (do_one_initcall+0x4c/0x28c)
(do_one_initcall) from (kernel_init_freeable+0x29c/0x378)
(kernel_init_freeable) from (kernel_init+0x8/0x110)
(kernel_init) from (ret_from_fork+0x14/0x2c)
Tested-by: Alan Tull <atull@kernel.org>
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Add checks:
- attempted kfree due to refcount reaching zero before overlay
is removed
- properties linked to an overlay node when the node is removed
- node refcount > one during node removal in a changeset destroy,
if the node was created by the changeset
After applying this patch, several validation warnings will be
reported from the devicetree unittest during boot due to
pre-existing devicetree bugs. The warnings will be similar to:
OF: ERROR: of_node_release(), unexpected properties in /testcase-data/overlay-node/test-bus/test-unittest11
OF: ERROR: memory leak, expected refcount 1 instead of 2, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node /testcase-data-2/substation@100/
hvac-medium-2
Tested-by: Alan Tull <atull@kernel.org>
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Ever since cdf7abc461 ("srcu: Allow use of Tiny/Tree SRCU from
both process and interrupt context"), it has been permissible
to use SRCU read-side critical sections in interrupt context.
This allows __call_srcu() to use SRCU read-side critical sections to
prevent a new SRCU grace period from ending before the call to either
srcu_funnel_gp_start() or srcu_funnel_exp_start completes, thus preventing
SRCU grace-period counter overflow during that time.
Note that this does not permit removal of the counter-wrap checks in
srcu_gp_end(). These check are necessary to handle the case where
a given CPU does not interact at all with SRCU for an extended time
period.
This commit therefore adds an SRCU read-side critical section to
__call_srcu() in order to prevent grace period counter wrap during
the funnel-locking process.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Fix kernel-doc warnings for missing parameter descriptions:
../include/linux/srcu.h:175: warning: Function parameter or member 'p' not described in 'srcu_dereference_notrace'
../include/linux/srcu.h:175: warning: Function parameter or member 'sp' not described in 'srcu_dereference_notrace'
Fixes: 0b764a6e4e ("srcu: Add notrace variant of srcu_dereference")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
lockdep_assert_held() is better suited to checking locking requirements,
since it only checks if the current thread holds the lock regardless of
whether someone else does. This is also a step towards possibly removing
spin_is_locked().
Signed-off-by: Lance Roy <ldr709@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <x86@kernel.org>
Cc: <linux-pci@vger.kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This reduces the size of the init executable from ~800 kB to ~800 bytes
on x86_64. This is only implemented for x86_64, i386, arm and arm64.
Others not tested.
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This is a definition of the most common syscalls needed in minimalist
init executables, allowing to statically build them with no external
dependencies. It is sufficient in its current form to build rcutorture's
init on x86_64, i386, arm, and arm64. Others have not been ported or
tested. Updates may be found here :
http://git.formilux.org/?p=people/willy/nolibc.git
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
If the build fails, we can end up with an empty initrd directory which
prevents the build script from operating again. Better rely on the
resulting init executable instead.
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Strip using -s on the compiler command line instead of calling the "strip"
utility as the latter isn't necessarily compatible with the target arch.
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This adds the CROSS_COMPILE environment to the initrd.sh script's
gcc command to enable cross compilation.
Reported-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Currently, the initrd/init script and executable remain blocked almost
all the time. However, it is necessary to test nohz_full userspace
execution, which both variants of initrd/init fail to do. This commit
therefore causes initrd/init to spend about a millisecond per second
executing in userspace.
Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The support for creating initrd directories using dracut is a great
improvement over having to always hand-create them, it is a bit annoying
to have to install some otherwise irrelevant package just to be able to
run rcutorture. This commit therefore adds support for creating initrd
directories on systems innocent of dracut. You do need gcc, but then
again you need that to build the kernel (or to build llvm) in any case.
The idea is to create an initrd directory containing nothing but a
statically linked binary having a for-loop over a long-term sleep().
The result is a Linux kernel with almost no userspace: even the
time-honored /dev, /lib, /tmp, and /usr directories are gone. In fact,
the only directory present is "/", but only because I don't know how to
get rid of it, at least short of not having an initrd in the first place.
Although statically linked binaries are much maligned, and rightly so,
their disadvantages seem to be irrelevant for this particular use case.
From https://www.akkadia.org/drepper/no_static_linking.html:
1. Fixes are difficult to apply to hordes of widely scattered
statically linked binaries. But in this case, there is only one
binary, but there would otherwise be no fewer than four libraries.
2. Security measures like local address randomization cannot be used.
Prudence prevents me from asserting that it is impossible to
base a remote attack on a networking-free rcutorture instance.
Nevertheless, bonus points to the first person who comes up with
such an attack!
3. More efficient use of physical memory. Not in this case, given
that libc is 1.8MB and the statically linked binary "only" 800K.
4. Features such as locales, name service switch (NSS),
internationalized domain names (IDN) tool, and so on require
dynamic linking. Bonus points to the first person coming up
with a valid rcutorture use case requiring these features in
its initrd.
5. Accidental violations of (L)GPL. Actually, this change actually
helps -avoid- such violations by reducing the temptation to
pass around tarballs of rcutorture-ready initrd directories.
After all, the rcutorture scripts automatically create an initrd
directory for you, so why bother with the tarballs?
6. Tools and hacks like ltrace, LD_PRELOAD, LD_PROFILE, and LD_AUDIT
don't work. Again, bonus points to the first person coming up
with a valid rcutorture use case requiring these features in
its initrd.
Nevertheless, the script will use dracut if available, and will create the
statically linked binary only when dracut are missing. Those preferring
the smaller initrd directory resulting from the statically linked binary
(like me) are free to hand-edit mkinitrd.sh to remove the code using
dracut. ;-)
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The rcutorture scripts currently expect the user to create the
tools/testing/selftests/rcutorture/initrd directory. Should the user
fail to do this, the kernel build will fail with obscure and confusing
error messages. This commit therefore adds explicit checks for the
tools/testing/selftests/rcutorture/initrd directory, and if not present,
creates one on systems on which dracut is installed. If this directory
could not be created, a less obscure error message is emitted and the
test is aborted.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Connor Shu <Connor.Shu@ibm.com>
[ paulmck: Adapt the script to fit into the rcutorture framework and
severely abbreviate the initrd/init script. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Consolidation of RCU-bh, RCU-preempt, and RCU-sched into one RCU flavor
to rule them all resulted in the removal of rcu_preempt_state. However,
stallwarn.txt still mentions rcu_preempt_state. This commit therefore
Updates stallwarn documentation accordingly.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: <kernel-team@android.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
RCU Data-Structures document describes a trick to test RCU with small
number of CPUs but with a taller tree. It wasn't immediately clear how
the document arrived at 16 CPUs which also requires setting the
FANOUT_LEAF to 2 instead of the default of 16. This commit therefore
provides the needed clarification.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: <kernel-team@android.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit adds a section to the requirements documentation setting down
requirements for grace-period and callback-invocation forward progress.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Now that call_rcu()'s callback is not invoked until after all
preempt-disable regions of code have completed (in addition to explicitly
marked RCU read-side critical sections), call_rcu() can be used in place
of call_rcu_sched(). This commit therefore makes that change.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: <linuxppc-dev@lists.ozlabs.org>
Now that call_rcu()'s callback is not invoked until after all
preempt-disable regions of code have completed (in addition to explicitly
marked RCU read-side critical sections), call_rcu() can be used in place
of call_rcu_sched(). This commit therefore makes that change.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <linux-s390@vger.kernel.org>
Now that synchronize_rcu() waits for preempt-disable regions of code
in addition to explicitly marked RCU read-side critical sections,
synchronize_rcu() can be used in place of synchronize_sched(). This
commit therefore makes that change.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Robert Richter <rric@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <oprofile-list@lists.sf.net>
Cc: <sparclinux@vger.kernel.org>
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, the synchronize_sched()
in sys_membarrier() can be replaced by synchronize_rcu(). This commit
therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
This commit retains all the various gp_ops[] entries, but makes their
update functions all be synchronize_rcu(), call_rcu() and rcu_barrier().
The read-side checks remain consistent with the various RCU flavors,
which still exist on the read side.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Now that synchronize_rcu() waits for both RCU read-side critical
sections and preempt-disabled regions of code, the sole caller of
synchronize_rcu_mult() can be replaced by synchronize_rcu().
This patch makes this change and removes synchronize_rcu_mult().
Note that _wait_rcu_gp() still supports synchronize_rcu_mult(),
and thus might be simplified in the future to take only take
a single call_rcu() function rather than the current list of them.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Recent changes have removed the old ->gp_seq_needed field from the
rcu_state structure, which in turn obsoleted a couple of comments in
the rcu_node and rcu_data structures. This commit therefore updates
these comments accordingly.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: <kernel-team@android.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The rcu_bh_state and rcu_sched_state variables were removed during the
RCU flavor consolidations, but external declarations remain in tree.h.
This commit therefore removes these obsolete declarations.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: <kernel-team@android.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The tree.c file has a number of calls to BUG_ON(), which panics the
kernel, which is not a good strategy for devices (like embedded) that
don't have a way to capture console output. This commit therefore
converts these BUG_ON() calls to WARN_ON_ONCE() and WARN_ONCE().
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The sync.c file has a number of calls to BUG_ON(), which panics the
kernel, which is not a good strategy for devices (like embedded) that
don't have a way to capture console output. This commit therefore
changes these BUG_ON() calls to WARN_ON_ONCE(), but does so quite naively.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Jakub Kicinski says:
====================
nfp: abm: move code and improve parameter validation
This set starts by separating Qdisc handling code into a new file.
Next two patches allow early access to TLV-based capabilities during
probe, previously the capabilities were parsed just before netdevs
were registered, but its cleaner to do some basic validation earlier
and avoid cleanup work.
Next three patches improve RED's parameter validation. First we provide
a more precise message about why offload failed (and move the parameter
validation to a helper). Next we make sure we don't set the top bit
in the 32 bit max RED threshold value. Because FW is treating the value
as signed it reportedly causes slow downs (unnecessary queuing and
marking) when top bit is set with recent firmwares. Last (and perhaps
least importantly) we offload the harddrop parameter of the Qdisc.
We don't plan to offload harddrop RED, but it seems prudent to make
sure user didn't set that flag as device behaviour would have differed.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
RED Qdisc will now inform the drivers about the state of the harddrop
flag. Refuse to offload in case harddrop is set.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To mirror software behaviour on offload more precisely inform
the drivers about the state of the harddrop flag.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Turns out the threshold value is used in signed compares in the FW,
so we should avoid setting the top bit.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Improve log messages printed when RED can't be offloaded because
of Qdisc parameters.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In certain cases initialization logic which follows allocation of
the vNIC structure may want to validate the capabilities of that vNIC.
This is easy before vNIC is initialized for normal capabilities which
are at fixed offsets in control memory, easy to locate and read, but
poses a challenge if the capabilities are in form of TLVs. Parse
the TLVs early on so other code can just access parsed info, instead
of having to do the parsing by itself.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move setting ctrl_bar pointer to the nfp_net_alloc function,
to make sure we can parse capabilities early in the following
patch.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Qdisc offload code is logically separate, and we will soon
do significant surgery on it to support more Qdiscs, so move
it to a separate file.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Recently, in commit ab408b6dc7 ("tcp: switch tcp and sch_fq to new
earliest departure time model"), the TCP BBR code switched to a new
approach of using an explicit bbr_pacing_margin_percent for shaving a
pacing rate "haircut", rather than the previous implict
approach. Update an old comment to reflect the new approach.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Michał Mirosław says:
====================
net: Use __vlan_hwaccel_*() helpers
This series removes from networking core and driver code an assumption
about how VLAN tag presence is stored in an skb. This will allow to free
up overloading of VLAN.CFI bit to incidate tag's presence.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This removes assumption than vlan_tci != 0 when tag is present.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
This removes assumptions about VLAN_TAG_PRESENT bit.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use __vlan_hwaccel_put_tag() to set vlan tag and proto fields.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
__skb_checksum_complete_head() and __skb_checksum_complete()
are both declared in skbuff.h, they fit better in skbuff.c
than datagram.c.
Cc: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The vlan configuration is not restored after interface donw/up sequence
(if dual-emac - both interfaces). Tested on am572x EVM.
Steps to check:
~# ip link add link eth1 name eth1.100 type vlan id 100
~# ifconfig eth0 down
~# ifconfig eth1 down
Try to remove vid and observe warning:
~# ip link del eth1.100
[ 739.526757] net eth1: removing vlanid 100 from vlan filter
[ 739.533322] failed to kill vid 0081/100 for device eth1
This patch fixes it, restoring only vlan ALE entries and all other
unicast/multicast entries are restored by system calling rx_mode ndo.
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
At this moment, mcast addresses are added for real device only
(reserved vlans for dual-emac mode), even if a mcast address was added
for some vlan only, thus ALE doesn't have corresponding vlan mcast
entries after vlan socket joined multicast group. So ALE drops vlan
frames with mcast addresses intended for vlans and potentially can
receive mcast frames for base ndev. That's not correct. So, fix it by
creating only vlan/mcast entries as requested. Patch doesn't use any
additional lists and is based on device mc address list and cpsw ALE
table entries.
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>