4476 Commits

Author SHA1 Message Date
Al Viro
9c5f6908de copy_{from,to}_user(): move kasan checks and might_fault() out-of-line
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-29 22:21:20 -04:00
Kees Cook
fd25d19f6b locking/refcount: Create unchecked atomic_t implementation
Many subsystems will not use refcount_t unless there is a way to build the
kernel so that there is no regression in speed compared to atomic_t. This
adds CONFIG_REFCOUNT_FULL to enable the full refcount_t implementation
which has the validation but is slightly slower. When not enabled,
refcount_t uses the basic unchecked atomic_t routines, which results in
no code changes compared to just using atomic_t directly.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Jann Horn <jannh@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Serge E. Hallyn <serge@hallyn.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: arozansk@redhat.com
Cc: axboe@kernel.dk
Cc: linux-arch <linux-arch@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170621200026.GA115679@beast
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-28 18:54:46 +02:00
Vladimir Murzin
25f1e18870 dma: Take into account dma_pfn_offset
Even though dma-noop-ops assumes 1:1 memory mapping DMA memory range
can be different to RAM. For example, ARM STM32F4 MCU offers the
possibility to remap SDRAM from 0xc000_0000 to 0x0 to get CPU
performance boost, but DMA continue to see SDRAM at 0xc000_0000. This
difference in mapping is handled via device-tree "dma-range" property
which leads to dev->dma_pfn_offset is set nonzero. To handle such
cases take dma_pfn_offset into account.

Cc: Joerg Roedel <jroedel@suse.de>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Reported-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Tested-by: Andras Szemzo <sza@esh.hu>
Tested-by: Alexandre TORGUE <alexandre.torgue@st.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-06-28 06:55:01 -07:00
Christoph Hellwig
3be6d9b6da dma-virt: remove dma_supported and mapping_error methods
These just duplicate the default behavior if no method is provided.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-06-28 06:54:41 -07:00
Christoph Hellwig
050d228a74 dma-noop: remove dma_supported and mapping_error methods
These just duplicate the default behavior if no method is provided.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-06-28 06:54:40 -07:00
Pantelis Antoniou
ce4fecf1fe vsprintf: Add %p extension "%pOF" for device tree
90% of the usage of device node's full_name is printing it out in a
kernel message. However, storing the full path for every node is
wasteful and redundant. With a custom format specifier, we can generate
the full path at run-time and eventually remove the full path from every
node.

For instance typical use is:
	pr_info("Frobbing node %s\n", node->full_name);

Which can be written now as:
	pr_info("Frobbing node %pOF\n", node);

'%pO' is the base specifier to represent kobjects with '%pOF'
representing struct device_node. Currently, struct device_node is the
only supported type of kobject.

More fine-grained control of formatting includes printing the name,
flags, path-spec name and others, explained in the documentation entry.

Originally written by Pantelis, but pretty much rewrote the core
function using existing string/number functions. The 2 passes were
unnecessary and have been removed. Also, updated the checkpatch.pl
check. The unittest code was written by Grant Likely.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2017-06-27 12:36:40 -05:00
Ingo Molnar
1bc3cd4dfa Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-24 08:57:20 +02:00
Ilya Matveychikov
a91e0f680b lib/cmdline.c: fix get_options() overflow while parsing ranges
When using get_options() it's possible to specify a range of numbers,
like 1-100500.  The problem is that it doesn't track array size while
calling internally to get_range() which iterates over the range and
fills the memory with numbers.

Link: http://lkml.kernel.org/r/2613C75C-B04D-4BFF-82A6-12F97BA0F620@gmail.com
Signed-off-by: Ilya V. Matveychikov <matvejchikov@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-23 16:15:55 -07:00
Ingo Molnar
f9e1698831 Merge branch 'linus' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-22 10:19:14 +02:00
Nikolay Borisov
104b4e5139 percpu_counter: Rename __percpu_counter_add to percpu_counter_add_batch
Currently, percpu_counter_add is a wrapper around __percpu_counter_add
which is preempt safe due to explicit calls to preempt_disable.  Given
how __ prefix is used in percpu related interfaces, the naming
unfortunately creates the false sense that __percpu_counter_add is
less safe than percpu_counter_add.  In terms of context-safety,
they're equivalent.  The only difference is that the __ version takes
a batch parameter.

Make this a bit more explicit by just renaming __percpu_counter_add to
percpu_counter_add_batch.

This patch doesn't cause any functional changes.

tj: Minor updates to patch description for clarity.  Cosmetic
    indentation updates.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Jan Kara <jack@suse.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: linux-mm@kvack.org
Cc: "David S. Miller" <davem@davemloft.net>
2017-06-20 15:42:32 -04:00
yuan linyu
b952f4dff2 net: manual clean code which call skb_put_[data:zero]
Signed-off-by: yuan linyu <Linyu.Yuan@alcatel-sbell.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-20 13:30:15 -04:00
yuan linyu
de77b966ce net: introduce __skb_put_[zero, data, u8]
follow Johannes Berg, semantic patch file as below,
@@
identifier p, p2;
expression len;
expression skb;
type t, t2;
@@
(
-p = __skb_put(skb, len);
+p = __skb_put_zero(skb, len);
|
-p = (t)__skb_put(skb, len);
+p = __skb_put_zero(skb, len);
)
... when != p
(
p2 = (t2)p;
-memset(p2, 0, len);
|
-memset(p, 0, len);
)

@@
identifier p;
expression len;
expression skb;
type t;
@@
(
-t p = __skb_put(skb, len);
+t p = __skb_put_zero(skb, len);
)
... when != p
(
-memset(p, 0, len);
)

@@
type t, t2;
identifier p, p2;
expression skb;
@@
t *p;
...
(
-p = __skb_put(skb, sizeof(t));
+p = __skb_put_zero(skb, sizeof(t));
|
-p = (t *)__skb_put(skb, sizeof(t));
+p = __skb_put_zero(skb, sizeof(t));
)
... when != p
(
p2 = (t2)p;
-memset(p2, 0, sizeof(*p));
|
-memset(p, 0, sizeof(*p));
)

@@
expression skb, len;
@@
-memset(__skb_put(skb, len), 0, len);
+__skb_put_zero(skb, len);

@@
expression skb, len, data;
@@
-memcpy(__skb_put(skb, len), data, len);
+__skb_put_data(skb, data, len);

@@
expression SKB, C, S;
typedef u8;
identifier fn = {__skb_put};
fresh identifier fn2 = fn ## "_u8";
@@
- *(u8 *)fn(SKB, S) = C;
+ fn2(SKB, C);

Signed-off-by: yuan linyu <Linyu.Yuan@alcatel-sbell.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-20 13:30:14 -04:00
Ingo Molnar
902b319413 Merge branch 'WIP.sched/core' into sched/core
Conflicts:
	kernel/sched/Makefile

Pick up the waitqueue related renames - it didn't get much feedback,
so it appears to be uncontroversial. Famous last words? ;-)

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20 12:28:21 +02:00
Jason A. Donenfeld
d06bfd1989 random: warn when kernel uses unseeded randomness
This enables an important dmesg notification about when drivers have
used the crng without it being seeded first. Prior, these errors would
occur silently, and so there hasn't been a great way of diagnosing these
types of bugs for obscure setups. By adding this as a config option, we
can leave it on by default, so that we learn where these issues happen,
in the field, will still allowing some people to turn it off, if they
really know what they're doing and do not want the log entries.

However, we don't leave it _completely_ by default. An earlier version
of this patch simply had `default y`. I'd really love that, but it turns
out, this problem with unseeded randomness being used is really quite
present and is going to take a long time to fix. Thus, as a compromise
between log-messages-for-all and nobody-knows, this is `default y`,
except it is also `depends on DEBUG_KERNEL`. This will ensure that the
curious see the messages while others don't have to.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-19 22:06:28 -04:00
Jason A. Donenfeld
d48ad080ec rhashtable: use get_random_u32 for hash_rnd
This is much faster and just as secure. It also has the added benefit of
probably returning better randomness at early-boot on systems with
architectural RNGs.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-19 22:06:28 -04:00
Johannes Berg
4df864c1d9 networking: make skb_put & friends return void pointers
It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:

    @@
    expression SKB, LEN;
    typedef u8;
    identifier fn = { skb_put, __skb_put };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_put, __skb_put };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

which actually doesn't cover pskb_put since there are only three
users overall.

A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-16 11:48:39 -04:00
Johannes Berg
59ae1d127a networking: introduce and use skb_put_data()
A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.

An spatch similar to the one for skb_put_zero() converts many
of the places using it:

    @@
    identifier p, p2;
    expression len, skb, data;
    type t, t2;
    @@
    (
    -p = skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    |
    -p = (t)skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, len);
    |
    -memcpy(p, data, len);
    )

    @@
    type t, t2;
    identifier p, p2;
    expression skb, data;
    @@
    t *p;
    ...
    (
    -p = skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    |
    -p = (t *)skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, sizeof(*p));
    |
    -memcpy(p, data, sizeof(*p));
    )

    @@
    expression skb, len, data;
    @@
    -memcpy(skb_put(skb, len), data, len);
    +skb_put_data(skb, data, len);

(again, manually post-processed to retain some comments)

Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-16 11:48:37 -04:00
David S. Miller
0ddead90b2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The conflicts were two cases of overlapping changes in
batman-adv and the qed driver.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-15 11:59:32 -04:00
Johannes Thumshirn
0945e56994 scatterlist: add sg_zero_buffer() helper
The sg_zero_buffer() helper is used to zero fill an area in a SG
list.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
[hch: renamed to sg_zero_buffer]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-06-15 14:30:14 +02:00
Linus Torvalds
54ed0f71f0 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fix from Herbert Xu:
 "This fixes a bug on sparc where we may dereference freed stack memory"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: Work around deallocated stack frame reference gcc bug on sparc.
2017-06-15 17:54:51 +09:00
David Daney
b7127cfea0 test_bpf: Add test to make conditional jump cross a large number of insns.
On MIPS, conditional branches can only span 32k instructions.  To
exceed this limit in the JIT with the BPF maximum of 4k insns, we need
to choose eBPF insns that expand to more than 8 machine instructions.
Use BPF_LD_ABS as it is quite complex.  This forces the JIT to invert
the sense of the branch to branch around a long jump to the end.

This (somewhat) verifies that the branch inversion logic and target
address calculation of the long jumps are done correctly.

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-14 15:03:22 -04:00
Johannes Berg
aa9f979c41 networking: use skb_put_zero()
Use the recently introduced helper to replace the pattern of
skb_put() && memset(), this transformation was done with the
following spatch:

@@
identifier p;
expression len;
expression skb;
@@
-p = skb_put(skb, len);
-memset(p, 0, len);
+p = skb_put_zero(skb, len);

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-13 13:54:03 -04:00
Greg Kroah-Hartman
069a0f32c9 Merge 4.12-rc5 into char-misc-next
We want the char/misc driver fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-12 08:18:10 +02:00
Dan Williams
0aed55af88 x86, uaccess: introduce copy_from_iter_flushcache for pmem / cache-bypass operations
The pmem driver has a need to transfer data with a persistent memory
destination and be able to rely on the fact that the destination writes are not
cached. It is sufficient for the writes to be flushed to a cpu-store-buffer
(non-temporal / "movnt" in x86 terms), as we expect userspace to call fsync()
to ensure data-writes have reached a power-fail-safe zone in the platform. The
fsync() triggers a REQ_FUA or REQ_FLUSH to the pmem driver which will turn
around and fence previous writes with an "sfence".

Implement a __copy_from_user_inatomic_flushcache, memcpy_page_flushcache, and
memcpy_flushcache, that guarantee that the destination buffer is not dirty in
the cpu cache on completion. The new copy_from_iter_flushcache and sub-routines
will be used to replace the "pmem api" (include/linux/pmem.h +
arch/x86/include/asm/pmem.h). The availability of copy_from_iter_flushcache()
and memcpy_flushcache() are gated by the CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
config symbol, and fallback to copy_from_iter_nocache() and plain memcpy()
otherwise.

This is meant to satisfy the concern from Linus that if a driver wants to do
something beyond the normal nocache semantics it should be something private to
that driver [1], and Al's concern that anything uaccess related belongs with
the rest of the uaccess code [2].

The first consumer of this interface is a new 'copy_from_iter' dax operation so
that pmem can inject cache maintenance operations without imposing this
overhead on other dax-capable drivers.

[1]: https://lists.01.org/pipermail/linux-nvdimm/2017-January/008364.html
[2]: https://lists.01.org/pipermail/linux-nvdimm/2017-April/009942.html

Cc: <x86@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-09 09:09:56 -07:00
Jeremy Kerr
0cbaa44841 lib: Add crc4 module
Add a little helper for crc4 calculations. This works 4-bits-at-a-time,
using a simple table approach.

We will need this in the FSI core code, as well as any master
implementations that need to calculate CRCs in software.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Chris Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09 11:52:07 +02:00
Paul E. McKenney
43a0a2a7d7 rcu: Move RCU debug Kconfig options to kernel/rcu
RCU's debugging Kconfig options are in the unintuitive location
lib/Kconfig.debug, and there are enough of them that it would be good for
them to be more centralized.  This commit therefore extracts RCU's Kconfig
options from init/Kconfig into a new kernel/rcu/Kconfig.debug file.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-06-08 18:52:44 -07:00
Paul E. McKenney
ae91aa0adb rcu: Remove debugfs tracing
RCU's debugfs tracing used to be the only reasonable low-level debug
information available, but ftrace and event tracing has since surpassed
the RCU debugfs level of usefulness.  This commit therefore removes
RCU's debugfs tracing.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-06-08 18:52:43 -07:00
Paul E. McKenney
41a2901e7d rcu: Remove SPARSE_RCU_POINTER Kconfig option
The sparse-based checking for non-RCU accesses to RCU-protected pointers
has been around for a very long time, and it is now the only type of
sparse-based checking that is optional.  This commit therefore makes
it unconditional.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
2017-06-08 18:52:41 -07:00
Paul E. McKenney
c4a09ff752 rcu: Remove the now-obsolete PROVE_RCU_REPEATEDLY Kconfig option
The PROVE_RCU_REPEATEDLY Kconfig option was initially added due to
the volume of messages from PROVE_RCU: Doing just one per boot would
have required excessive numbers of boots to locate them all.  However,
PROVE_RCU messages are now relatively rare, so there is no longer any
reason to need more than one such message per boot.  This commit therefore
removes the PROVE_RCU_REPEATEDLY Kconfig option.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
2017-06-08 18:52:41 -07:00
Paul E. McKenney
90040c9e30 rcu: Remove *_SLOW_* Kconfig options
The RCU_TORTURE_TEST_SLOW_PREINIT, RCU_TORTURE_TEST_SLOW_PREINIT_DELAY,
RCU_TORTURE_TEST_SLOW_PREINIT_DELAY, RCU_TORTURE_TEST_SLOW_INIT,
RCU_TORTURE_TEST_SLOW_INIT_DELAY, RCU_TORTURE_TEST_SLOW_CLEANUP,
and RCU_TORTURE_TEST_SLOW_CLEANUP_DELAY Kconfig options are only
useful for torture testing, and there are the rcutree.gp_cleanup_delay,
rcutree.gp_init_delay, and rcutree.gp_preinit_delay kernel boot parameters
that rcutorture can use instead.  The effect of these parameters is to
artificially slow down grace period initialization and cleanup in order
to make some types of race conditions happen more often.

This commit therefore simplifies Tree RCU a bit by removing the Kconfig
options and adding the corresponding kernel parameters to rcutorture's
.boot files instead.  However, this commit also leaves out the kernel
parameters for TREE02, TREE04, and TREE07 in order to have about the
same number of tests slowed as not slowed.  TREE01, TREE03, TREE05,
and TREE06 are slowed, and the rest are not slowed.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-06-08 18:52:38 -07:00
David Miller
d41519a69b crypto: Work around deallocated stack frame reference gcc bug on sparc.
On sparc, if we have an alloca() like situation, as is the case with
SHASH_DESC_ON_STACK(), we can end up referencing deallocated stack
memory.  The result can be that the value is clobbered if a trap
or interrupt arrives at just the right instruction.

It only occurs if the function ends returning a value from that
alloca() area and that value can be placed into the return value
register using a single instruction.

For example, in lib/libcrc32c.c:crc32c() we end up with a return
sequence like:

        return  %i7+8
         lduw   [%o5+16], %o0   ! MEM[(u32 *)__shash_desc.1_10 + 16B],

%o5 holds the base of the on-stack area allocated for the shash
descriptor.  But the return released the stack frame and the
register window.

So if an intererupt arrives between 'return' and 'lduw', then
the value read at %o5+16 can be corrupted.

Add a data compiler barrier to work around this problem.  This is
exactly what the gcc fix will end up doing as well, and it absolutely
should not change the code generated for other cpus (unless gcc
on them has the same bug :-)

With crucial insight from Eric Sandeen.

Cc: <stable@vger.kernel.org>
Reported-by: Anatoly Pugachev <matorola@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-06-08 17:36:03 +08:00
Peter Zijlstra
018956d641 locking/selftest: Add RT-mutex support
Now that RT-mutex has lockdep annotations, add them to the selftest.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-08 10:35:50 +02:00
Peter Zijlstra
cfb6133399 locking/selftest: Remove the bad unlock ordering test
There is no such thing as a bad unlock order.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-08 10:35:49 +02:00
Peter Zijlstra
f5694788ad rt_mutex: Add lockdep annotations
Now that (PI) futexes have their own private RT-mutex interface and
implementation we can easily add lockdep annotations to the existing
RT-mutex interface.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-08 10:35:49 +02:00
Christoph Hellwig
ef40dda5bb uuid: hoist uuid_is_null() helper from libnvdimm
Hoist the libnvdimm helper as an inline helper to linux/uuid.h
using an auxiliary const variable uuid_null in lib/uuid.c.

[hch: also add the guid variant.  Both do the same but I'd like
to keep casts to a minimum]

The common helper uses the new abstract type uuid_t * instead of
u8 *.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
[hch: added guid_is_null]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2017-06-05 16:59:05 +02:00
Christoph Hellwig
df33767d9f uuid: hoist helpers uuid_equal() and uuid_copy() from xfs
These helper are used to compare and copy two uuid_t type objects.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
[hch: also provide the respective guid_ versions]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2017-06-05 16:59:04 +02:00
Christoph Hellwig
b10bf0e281 uuid: don't export guid_index and uuid_index
These are only used in uuid.c and vsprintf.c and aren't something modules
should use directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2017-06-05 16:59:03 +02:00
Christoph Hellwig
f9727a17db uuid: rename uuid types
Our "little endian" UUID really is a Wintel GUID, so rename it and its
helpers such (guid_t).  The big endian UUID is the only true one, so
give it the name uuid_t.  The uuid_le and uuid_be names are retained for
now, but will hopefully go away soon.  The exception to that are the _cmp
helpers that will be replaced by better primitives ASAP and thus don't
get the new names.

Also the _to_bin helpers are named to match the better named uuid_parse
routine in userspace.

Also remove the existing typedef in XFS that's now been superceeded by
the generic type name.

Signed-off-by: Christoph Hellwig <hch@lst.de>
[andy: also update the UUID_LE/UUID_BE macros including fallout]
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-06-05 16:58:59 +02:00
Alexei Starovoitov
105c03614b bpf: fix stack_depth usage by test_bpf.ko
test_bpf.ko doesn't call verifier before selecting interpreter or JITing,
hence the tests need to manually specify the amount of stack they consume.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-31 19:29:48 -04:00
David Daney
791caeb084 test_bpf: Add a couple of tests for BPF_JSGE.
Some JITs can optimize comparisons with zero.  Add a couple of
BPF_JSGE tests against immediate zero.

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-25 14:37:56 -04:00
Peter Rajnoha
f36776fafb kobject: support passing in variables for synthetic uevents
This patch makes it possible to pass additional arguments in addition
to uevent action name when writing /sys/.../uevent attribute. These
additional arguments are then inserted into generated synthetic uevent
as additional environment variables.

Before, we were not able to pass any additional uevent environment
variables for synthetic uevents. This made it hard to identify such uevents
properly in userspace to make proper distinction between genuine uevents
originating from kernel and synthetic uevents triggered from userspace.
Also, it was not possible to pass any additional information which would
make it possible to optimize and change the way the synthetic uevents are
processed back in userspace based on the originating environment of the
triggering action in userspace. With the extra additional variables, we are
able to pass through this extra information needed and also it makes it
possible to synchronize with such synthetic uevents as they can be clearly
identified back in userspace.

The format for writing the uevent attribute is following:

    ACTION [UUID [KEY=VALUE ...]

There's no change in how "ACTION" is recognized - it stays the same
("add", "change", "remove"). The "ACTION" is the only argument required
to generate synthetic uevent, the rest of arguments, that this patch
adds support for, are optional.

The "UUID" is considered as transaction identifier so it's possible to
use the same UUID value for one or more synthetic uevents in which case
we logically group these uevents together for any userspace listeners.
The "UUID" is expected to be in "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
format where "x" is a hex digit. The value appears in uevent as
"SYNTH_UUID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" environment variable.

The "KEY=VALUE" pairs can contain alphanumeric characters only. It's
possible to define zero or more more pairs - each pair is then delimited
by a space character " ". Each pair appears in synthetic uevents as
"SYNTH_ARG_KEY=VALUE" environment variable. That means the KEY name gains
"SYNTH_ARG_" prefix to avoid possible collisions with existing variables.
To pass the "KEY=VALUE" pairs, it's also required to pass in the "UUID"
part for the synthetic uevent first.

If "UUID" is not passed in, the generated synthetic uevent gains
"SYNTH_UUID=0" environment variable automatically so it's possible to
identify this situation in userspace when reading generated uevent and so
we can still make a difference between genuine and synthetic uevents.

Signed-off-by: Peter Rajnoha <prajnoha@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 18:30:51 +02:00
Thomas Gleixner
1c3c5eab17 sched/core: Enable might_sleep() and smp_processor_id() checks early
might_sleep() and smp_processor_id() checks are enabled after the boot
process is done. That hides bugs in the SMP bringup and driver
initialization code.

Enable it right when the scheduler starts working, i.e. when init task and
kthreadd have been created and right before the idle task enables
preemption.

Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170516184736.272225698@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-23 10:01:38 +02:00
Petr Mladek
719f6a7040 printk: Use the main logbuf in NMI when logbuf_lock is available
The commit 42a0bb3f71383b457a7d ("printk/nmi: generic solution for safe
printk in NMI") caused that printk stores messages into a temporary
buffer in NMI context.

The buffer is per-CPU and therefore the size is rather limited.
It works quite well for NMI backtraces. But there are longer logs
that might get printed in NMI context, for example, lockdep
warnings, ftrace_dump_on_oops.

The temporary buffer is used to avoid deadlocks caused by
logbuf_lock. Also it is needed to avoid races with the other
temporary buffer that is used when PRINTK_SAFE_CONTEXT is entered.
But the main buffer can be used in NMI if the lock is available
and we did not interrupt PRINTK_SAFE_CONTEXT.

The lock is checked using raw_spin_is_locked(). It might cause
false negatives when the lock is taken on another CPU and
this CPU is in the safe context from other reasons. Note that
the safe context is used also to get console semaphore or when
calling console drivers. For this reason, we do the check in
printk_nmi_enter(). It makes the handling consistent for
the entire NMI handler and avoids reshuffling of the messages.

The patch also defines special printk context that allows
to use printk_deferred() in NMI. Note that we could not flush
the messages to the consoles because console drivers might use
many other internal locks.

The newly created vprintk_deferred() disables the preemption
only around the irq work handling. It is needed there to keep
the consistency between the two per-CPU variables. But there
is no reason to disable preemption around vprintk_emit().

Finally, the patch puts back explicit serialization of the NMI
backtraces from different CPUs. It was removed by the
commit a9edc88093287183ac934b ("x86/nmi: Perform a safe
NMI stack trace on all CPUs"). It was not needed because
the flushing of the temporary per-CPU buffers was serialized.

Link: http://lkml.kernel.org/r/1493912763-24873-1-git-send-email-pmladek@suse.com
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <rack+kernel@arm.linux.org.uk>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: x86@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2017-05-19 14:42:19 +02:00
Jonathan Corbet
6312811be2 Merge remote-tracking branch 'mauro-exp/docbook3' into death-to-docbook
Mauro says:

This patch series convert the remaining DocBooks to ReST.

The first version was originally
send as 3 patch series:

   [PATCH 00/36] Convert DocBook documents to ReST
   [PATCH 0/5] Convert more books to ReST
   [PATCH 00/13] Get rid of DocBook

The lsm book was added as if it were a text file under
Documentation. The plan is to merge it with another file
under Documentation/security, after both this series and
a security Documentation patch series gets merged.

It also adjusts some Sphinx-pedantic errors/warnings on
some kernel-doc markups.

I also added some patches here to add PDF output for all
existing ReST books.
2017-05-18 11:03:08 -06:00
Mauro Carvalho Chehab
08c76a2f43 lib: update location of kgdb documentation
The documentation was moved from DocBook directory.
Update its location.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-05-16 08:44:22 -03:00
Mauro Carvalho Chehab
e1b4fc7add fs: update location of filesystems documentation
The filesystem documentation was moved from DocBook to
Documentation/filesystems/. Update it at the sources.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-05-16 08:44:22 -03:00
Anup Patel
b5dceda1f7 lib/raid6: Add log-of-2 table for RAID6 HW requiring disk position
The raid6_gfexp table represents {2}^n values for 0 <= n < 256. The
Linux async_tx framework pass values from raid6_gfexp as coefficients
for each source to prep_dma_pq() callback of DMA channel with PQ
capability. This creates problem for RAID6 offload engines (such as
Broadcom SBA) which take disk position (i.e. log of {2}) instead of
multiplicative cofficients from raid6_gfexp table.

This patch adds raid6_gflog table having log-of-2 value for any given
x such that 0 <= x < 256. For any given disk coefficient x, the
corresponding disk position is given by raid6_gflog[x]. The RAID6
offload engine driver can use this newly added raid6_gflog table to
get disk position from multiplicative coefficient.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Acked-by: Shaohua Li <shli@fb.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-05-16 10:01:57 +05:30
Al Viro
8298525839 kill strlen_user()
no callers, no consistent semantics, no sane way to use it...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-05-15 23:40:22 -04:00
Peter Zijlstra
c743f0a5c5 sched/fair, cpumask: Export for_each_cpu_wrap()
More users for for_each_cpu_wrap() have appeared. Promote the construct
to generic cpumask interface.

The implementation is slightly modified to reduce arguments.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Lauro Ramos Venancio <lvenanci@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: lwang@redhat.com
Link: http://lkml.kernel.org/r/20170414122005.o35me2h5nowqkxbv@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-15 10:15:23 +02:00
Linus Torvalds
4879b7ae05 dmaengine updates for 4.12-rc1
This time again a smaller update consisting of:
 
 - support for TI DA8xx dma controller and updates to the cppi driver
 - updates on bunch of drivers like xilinx, pl08x, stm32-dma, mv_xor, ioat,
   dmatest
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Merge tag 'dmaengine-4.12-rc1' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine updates from Vinod Koul:
 "This time again a smaller update consisting of:

   - support for TI DA8xx dma controller and updates to the cppi driver

   - updates on bunch of drivers like xilinx, pl08x, stm32-dma, mv_xor,
     ioat, dmatest"

* tag 'dmaengine-4.12-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (35 commits)
  dmaengine: pl08x: remove lock documentation
  dmaengine: pl08x: fix pl08x_dma_chan_state documentation
  dmaengine: pl08x: Use the BIT() macro consistently
  dmaengine: pl080: Fix some missing kerneldoc
  dmaengine: pl080: Cut some unused defines
  dmaengine: dmatest: Add check for supported buffer count (sg_buffers)
  dmaengine: dmatest: Select DMA_ENGINE_RAID as its needed for the slave_sg test
  dmaengine: virt-dma: Convert to use list_for_each_entry_safe()
  dma-debug: use offset_in_page() macro
  dmaengine: mv_xor: use offset_in_page() macro
  dmaengine: dmatest: use offset_in_page() macro
  dmaengine: sun4i: fix invalid argument
  dmaengine: ioat: use setup_timer
  dmaengine: cppi41: Fix an Oops happening in cppi41_dma_probe()
  dmaengine: pl330: remove pdata based initialization
  dmaengine: cppi: fix build error due to bad variable
  dmaengine: imx-sdma: add 1ms delay to ensure SDMA channel is stopped
  dmaengine: cppi41: use managed functions devm_*()
  dmaengine: cppi41: fix cppi41_dma_tx_status() logic
  dmaengine: qcom_hidma: pause the channel on shutdown
  ...
2017-05-09 15:40:28 -07:00