Commit Graph

4727 Commits

Author SHA1 Message Date
Linus Torvalds
f36b7534b8 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "13 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, thp: do not cause memcg oom for thp
  mm/vmscan: wake up flushers for legacy cgroups too
  Revert "mm: page_alloc: skip over regions of invalid pfns where possible"
  mm/shmem: do not wait for lock_page() in shmem_unused_huge_shrink()
  mm/thp: do not wait for lock_page() in deferred_split_scan()
  mm/khugepaged.c: convert VM_BUG_ON() to collapse fail
  x86/mm: implement free pmd/pte page interfaces
  mm/vmalloc: add interfaces to free unmapped page table
  h8300: remove extraneous __BIG_ENDIAN definition
  hugetlbfs: check for pgoff value overflow
  lockdep: fix fs_reclaim warning
  MAINTAINERS: update Mark Fasheh's e-mail
  mm/mempolicy.c: avoid use uninitialized preferred_node
2018-03-22 18:48:43 -07:00
Toshi Kani
b6bdb7517c mm/vmalloc: add interfaces to free unmapped page table
On architectures with CONFIG_HAVE_ARCH_HUGE_VMAP set, ioremap() may
create pud/pmd mappings.  A kernel panic was observed on arm64 systems
with Cortex-A75 in the following steps as described by Hanjun Guo.

 1. ioremap a 4K size, valid page table will build,
 2. iounmap it, pte0 will set to 0;
 3. ioremap the same address with 2M size, pgd/pmd is unchanged,
    then set the a new value for pmd;
 4. pte0 is leaked;
 5. CPU may meet exception because the old pmd is still in TLB,
    which will lead to kernel panic.

This panic is not reproducible on x86.  INVLPG, called from iounmap,
purges all levels of entries associated with purged address on x86.  x86
still has memory leak.

The patch changes the ioremap path to free unmapped page table(s) since
doing so in the unmap path has the following issues:

 - The iounmap() path is shared with vunmap(). Since vmap() only
   supports pte mappings, making vunmap() to free a pte page is an
   overhead for regular vmap users as they do not need a pte page freed
   up.

 - Checking if all entries in a pte page are cleared in the unmap path
   is racy, and serializing this check is expensive.

 - The unmap path calls free_vmap_area_noflush() to do lazy TLB purges.
   Clearing a pud/pmd entry before the lazy TLB purges needs extra TLB
   purge.

Add two interfaces, pud_free_pmd_page() and pmd_free_pte_page(), which
clear a given pud/pmd entry and free up a page for the lower level
entries.

This patch implements their stub functions on x86 and arm64, which work
as workaround.

[akpm@linux-foundation.org: fix typo in pmd_free_pte_page() stub]
Link: http://lkml.kernel.org/r/20180314180155.19492-2-toshi.kani@hpe.com
Fixes: e61ce6ade4 ("mm: change ioremap to set up huge I/O mappings")
Reported-by: Lei Li <lious.lilei@hisilicon.com>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Wang Xuefeng <wxf.wang@hisilicon.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Chintan Pandya <cpandya@codeaurora.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-03-22 17:07:01 -07:00
Linus Torvalds
c4f4d2f917 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Always validate XFRM esn replay attribute, from Florian Westphal.

 2) Fix RCU read lock imbalance in xfrm_get_tos(), from Xin Long.

 3) Don't try to get firmware dump if not loaded in iwlwifi, from Shaul
    Triebitz.

 4) Fix BPF helpers to deal with SCTP GSO SKBs properly, from Daniel
    Axtens.

 5) Fix some interrupt handling issues in e1000e driver, from Benjamin
    Poitier.

 6) Use strlcpy() in several ethtool get_strings methods, from Florian
    Fainelli.

 7) Fix rhlist dup insertion, from Paul Blakey.

 8) Fix SKB leak in netem packet scheduler, from Alexey Kodanev.

 9) Fix driver unload crash when link is up in smsc911x, from Jeremy
    Linton.

10) Purge out invalid socket types in l2tp_tunnel_create(), from Eric
    Dumazet.

11) Need to purge the write queue when TCP connections are aborted,
    otherwise userspace using MSG_ZEROCOPY can't close the fd. From
    Soheil Hassas Yeganeh.

12) Fix double free in error path of team driver, from Arkadi
    Sharshevsky.

13) Filter fixes for hv_netvsc driver, from Stephen Hemminger.

14) Fix non-linear packet access in ipv6 ndisc code, from Lorenzo
    Bianconi.

15) Properly filter out unsupported feature flags in macvlan driver,
    from Shannon Nelson.

16) Don't request loading the diag module for a protocol if the protocol
    itself is not even registered. From Xin Long.

17) If datagram connect fails in ipv6, make sure the socket state is
    consistent afterwards. From Paolo Abeni.

18) Use after free in qed driver, from Dan Carpenter.

19) If received ipv4 PMTU is less than the min pmtu, lock the mtu in the
    entry. From Sabrina Dubroca.

20) Fix sleep in atomic in tg3 driver, from Jonathan Toppins.

21) Fix vlan in vlan untagging in some situations, from Toshiaki Makita.

22) Fix double SKB free in genlmsg_mcast(). From Nicolas Dichtel.

23) Fix NULL derefs in error paths of tcf_*_init(), from Davide Caratti.

24) Unbalanced PM runtime calls in FEC driver, from Florian Fainelli.

25) Memory leak in gemini driver, from Igor Pylypiv.

26) IDR leaks in error paths of tcf_*_init() functions, from Davide
    Caratti.

27) Need to use GFP_ATOMIC in seg6_build_state(), from David Lebrun.

28) Missing dev_put() in error path of macsec_newlink(), from Dan
    Carpenter.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (201 commits)
  macsec: missing dev_put() on error in macsec_newlink()
  net: dsa: Fix functional dsa-loop dependency on FIXED_PHY
  hv_netvsc: common detach logic
  hv_netvsc: change GPAD teardown order on older versions
  hv_netvsc: use RCU to fix concurrent rx and queue changes
  hv_netvsc: disable NAPI before channel close
  net/ipv6: Handle onlink flag with multipath routes
  ppp: avoid loop in xmit recursion detection code
  ipv6: sr: fix NULL pointer dereference when setting encap source address
  ipv6: sr: fix scheduling in RCU when creating seg6 lwtunnel state
  net: aquantia: driver version bump
  net: aquantia: Implement pci shutdown callback
  net: aquantia: Allow live mac address changes
  net: aquantia: Add tx clean budget and valid budget handling logic
  net: aquantia: Change inefficient wait loop on fw data reads
  net: aquantia: Fix a regression with reset on old firmware
  net: aquantia: Fix hardware reset when SPI may rarely hangup
  s390/qeth: on channel error, reject further cmd requests
  s390/qeth: lock read device while queueing next buffer
  s390/qeth: when thread completes, wake up all waiters
  ...
2018-03-22 14:10:29 -07:00
Thadeu Lima de Souza Cascardo
52fda36d63 test_bpf: Fix testing with CONFIG_BPF_JIT_ALWAYS_ON=y on other arches
Function bpf_fill_maxinsns11 is designed to not be able to be JITed on
x86_64. So, it fails when CONFIG_BPF_JIT_ALWAYS_ON=y, and
commit 09584b4067 ("bpf: fix selftests/bpf test_kmod.sh failure when
CONFIG_BPF_JIT_ALWAYS_ON=y") makes sure that failure is detected on that
case.

However, it does not fail on other architectures, which have a different
JIT compiler design. So, test_bpf has started to fail to load on those.

After this fix, test_bpf loads fine on both x86_64 and ppc64el.

Fixes: 09584b4067 ("bpf: fix selftests/bpf test_kmod.sh failure when CONFIG_BPF_JIT_ALWAYS_ON=y")
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-20 23:04:30 +01:00
Linus Torvalds
0d707a2f24 Merge branch 'for-4.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu fixes from Tejun Heo:
 "Late percpu pull request for v4.16-rc6.

   - percpu allocator pool replenishing no longer triggers OOM or
     warning messages.

     Also, the alloc interface now understands __GFP_NORETRY and
     __GFP_NOWARN. This is to allow avoiding OOMs from userland
     triggered actions like bpf map creation.

     Also added cond_resched() in alloc loop.

   - perpcu allocation now can be interrupted by kill sigs to avoid
     deadlocking OOM killer.

   - Added Dennis Zhou as a co-maintainer.

     He has rewritten the area map allocator, understands most of the
     code base and has been responsive for all bug reports"

* 'for-4.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu_ref: Update doc to dissuade users from depending on internal RCU grace periods
  mm: Allow to kill tasks doing pcpu_alloc() and waiting for pcpu_balance_workfn()
  percpu: include linux/sched.h for cond_resched()
  percpu: add a schedule point in pcpu_balance_workfn()
  percpu: allow select gfp to be passed to underlying allocators
  percpu: add __GFP_NORETRY semantics to the percpu balancing path
  percpu: match chunk allocator declarations with definitions
  percpu: add Dennis Zhou as a percpu co-maintainer
2018-03-19 14:48:35 -07:00
Tejun Heo
b3a5d11199 percpu_ref: Update doc to dissuade users from depending on internal RCU grace periods
percpu_ref internally uses sched-RCU to implement the percpu -> atomic
mode switching and the documentation suggested that this could be
depended upon.  This doesn't seem like a good idea.

* percpu_ref uses sched-RCU which has different grace periods regular
  RCU.  Users may combine percpu_ref with regular RCU usage and
  incorrectly believe that regular RCU grace periods are performed by
  percpu_ref.  This can lead to, for example, use-after-free due to
  premature freeing.

* percpu_ref has a grace period when switching from percpu to atomic
  mode.  It doesn't have one between the last put and release.  This
  distinction is subtle and can lead to surprising bugs.

* percpu_ref allows starting in and switching to atomic mode manually
  for debugging and other purposes.  This means that there may not be
  any grace periods from kill to release.

This patch makes it clear that the grace periods are percpu_ref's
internal implementation detail and can't be depended upon by the
users.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2018-03-19 10:09:44 -07:00
Joern Engel
8df3aaaf9b btree: avoid variable-length allocations
geo->keylen cannot be larger than 4.  So we might as well make
fixed-size allocations.

Given the one remaining user, geo->keylen cannot even be larger than 1.
Logfs used to have 64bit and 128bit keys, tcm_qla2xxx only has 32bit
keys.  But let's not break the code if we don't have to.

Signed-off-by: Joern Engel <joern@purestorage.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-03-14 16:55:29 -07:00
Luis R. Rodriguez
ac68b1b3b9 lib/test_kmod.c: fix limit check on number of test devices created
As reported by Dan the parentheses is in the wrong place, and since
unlikely() call returns either 0 or 1 it's never less than zero.  The
second issue is that signed integer overflows like "INT_MAX + 1" are
undefined behavior.

Since num_test_devs represents the number of devices, we want to stop
prior to hitting the max, and not rely on the wrap arround at all.  So
just cap at num_test_devs + 1, prior to assigning a new device.

Link: http://lkml.kernel.org/r/20180224030046.24238-1-mcgrof@kernel.org
Fixes: d9c6a72d6f ("kmod: add test driver to stress test the module loader")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-03-09 16:40:02 -08:00
Kees Cook
1b4cfe3c0a lib/bug.c: exclude non-BUG/WARN exceptions from report_bug()
Commit b8347c2196 ("x86/debug: Handle warnings before the notifier
chain, to fix KGDB crash") changed the ordering of fixups, and did not
take into account the case of x86 processing non-WARN() and non-BUG()
exceptions.  This would lead to output of a false BUG line with no other
information.

In the case of a refcount exception, it would be immediately followed by
the refcount WARN(), producing very strange double-"cut here":

  lkdtm: attempting bad refcount_inc() overflow
  ------------[ cut here ]------------
  Kernel BUG at 0000000065f29de5 [verbose debug info unavailable]
  ------------[ cut here ]------------
  refcount_t overflow at lkdtm_REFCOUNT_INC_OVERFLOW+0x6b/0x90 in cat[3065], uid/euid: 0/0
  WARNING: CPU: 0 PID: 3065 at kernel/panic.c:657 refcount_error_report+0x9a/0xa4
  ...

In the prior ordering, exceptions were searched first:

   do_trap_no_signal(struct task_struct *tsk, int trapnr, char *str,
   ...
                if (fixup_exception(regs, trapnr))
                        return 0;

  -               if (fixup_bug(regs, trapnr))
  -                       return 0;
  -

As a result, fixup_bugs()'s is_valid_bugaddr() didn't take into account
needing to search the exception list first, since that had already
happened.

So, instead of searching the exception list twice (once in
is_valid_bugaddr() and then again in fixup_exception()), just add a
simple sanity check to report_bug() that will immediately bail out if a
BUG() (or WARN()) entry is not found.

Link: http://lkml.kernel.org/r/20180301225934.GA34350@beast
Fixes: b8347c2196 ("x86/debug: Handle warnings before the notifier chain, to fix KGDB crash")
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Richard Weinberger <richard.weinberger@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-03-09 16:40:01 -08:00
Kees Cook
0862ca422b bug: use %pB in BUG and stack protector failure
The BUG and stack protector reports were still using a raw %p.  This
changes it to %pB for more meaningful output.

Link: http://lkml.kernel.org/r/20180301225704.GA34198@beast
Fixes: ad67b74d24 ("printk: hash addresses printed with %p")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Richard Weinberger <richard.weinberger@gmail.com>,
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-03-09 16:40:01 -08:00
Paul Blakey
499ac3b60f test_rhashtable: add test case for rhltable with duplicate objects
Tries to insert duplicates in the middle of bucket's chain:
bucket 1:  [[val 21 (tid=1)]] -> [[ val 1 (tid=2),  val 1 (tid=0) ]]

Reuses tid to distinguish the elements insertion order.

Signed-off-by: Paul Blakey <paulb@mellanox.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-07 10:44:03 -05:00
Paul Blakey
d3dcf8eb61 rhashtable: Fix rhlist duplicates insertion
When inserting duplicate objects (those with the same key),
current rhlist implementation messes up the chain pointers by
updating the bucket pointer instead of prev next pointer to the
newly inserted node. This causes missing elements on removal and
travesal.

Fix that by properly updating pprev pointer to point to
the correct rhash_head next pointer.

Issue: 1241076
Change-Id: I86b2c140bcb4aeb10b70a72a267ff590bb2b17e7
Fixes: ca26893f05 ('rhashtable: Add rhlist interface')
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-07 10:44:02 -05:00
Linus Torvalds
547046141f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Use an appropriate TSQ pacing shift in mac80211, from Toke
    Høiland-Jørgensen.

 2) Just like ipv4's ip_route_me_harder(), we have to use skb_to_full_sk
    in ip6_route_me_harder, from Eric Dumazet.

 3) Fix several shutdown races and similar other problems in l2tp, from
    James Chapman.

 4) Handle missing XDP flush properly in tuntap, for real this time.
    From Jason Wang.

 5) Out-of-bounds access in powerpc ebpf tailcalls, from Daniel
    Borkmann.

 6) Fix phy_resume() locking, from Andrew Lunn.

 7) IFLA_MTU values are ignored on newlink for some tunnel types, fix
    from Xin Long.

 8) Revert F-RTO middle box workarounds, they only handle one dimension
    of the problem. From Yuchung Cheng.

 9) Fix socket refcounting in RDS, from Ka-Cheong Poon.

10) Don't allow ppp unit registration to an unregistered channel, from
    Guillaume Nault.

11) Various hv_netvsc fixes from Stephen Hemminger.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (98 commits)
  hv_netvsc: propagate rx filters to VF
  hv_netvsc: filter multicast/broadcast
  hv_netvsc: defer queue selection to VF
  hv_netvsc: use napi_schedule_irqoff
  hv_netvsc: fix race in napi poll when rescheduling
  hv_netvsc: cancel subchannel setup before halting device
  hv_netvsc: fix error unwind handling if vmbus_open fails
  hv_netvsc: only wake transmit queue if link is up
  hv_netvsc: avoid retry on send during shutdown
  virtio-net: re enable XDP_REDIRECT for mergeable buffer
  ppp: prevent unregistered channels from connecting to PPP units
  tc-testing: skbmod: fix match value of ethertype
  mlxsw: spectrum_switchdev: Check success of FDB add operation
  net: make skb_gso_*_seglen functions private
  net: xfrm: use skb_gso_validate_network_len() to check gso sizes
  net: sched: tbf: handle GSO_BY_FRAGS case in enqueue
  net: rename skb_gso_validate_mtu -> skb_gso_validate_network_len
  rds: Incorrect reference counting in TCP socket creation
  net: ethtool: don't ignore return from driver get_fecparam method
  vrf: check forwarding on the original netdevice when generating ICMP dest unreachable
  ...
2018-03-05 11:29:24 -08:00
David S. Miller
a5f7b0eeb2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-02-28

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Add schedule points and reduce the number of loop iterations
   the test_bpf kernel module is performing in order to not hog
   the CPU for too long, from Eric.

2) Fix an out of bounds access in tail calls in the ppc64 BPF
   JIT compiler, from Daniel.

3) Fix a crash on arm64 on unaligned BPF xadd operations that
   could be triggered via interpreter and JIT, from Daniel.

Please not that once you merge net into net-next at some point, there
is a minor merge conflict in test_verifier.c since test cases had
been added at the end in both trees. Resolution is trivial: keep all
the test cases from both trees.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-01 21:42:07 -05:00
Linus Torvalds
b1aad6824a A single fix for a memory leak regression in the dma-debug code.
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Merge tag 'dma-mapping-4.16-3' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fix from Christoph Hellwig:
 "A single fix for a memory leak regression in the dma-debug code"

* tag 'dma-mapping-4.16-3' of git://git.infradead.org/users/hch/dma-mapping:
  dma-debug: fix memory leak in debug_dma_alloc_coherent
2018-02-28 11:13:08 -08:00
Eric Dumazet
9960d7669e test_bpf: reduce MAX_TESTRUNS
For tests that are using the maximal number of BPF instruction, each
run takes 20 usec. Looping 10,000 times on them totals 200 ms, which
is bad when the loop is not preemptible.

test_bpf: #264 BPF_MAXINSNS: Call heavy transformations jited:1 19248
18548 PASS
test_bpf: #269 BPF_MAXINSNS: ld_abs+get_processor_id jited:1 20896 PASS

Lets divide by ten the number of iterations, so that max latency is
20ms. We could use need_resched() to break the loop earlier if we
believe 20 ms is too much.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-28 17:49:18 +01:00
Eric Dumazet
d40bc96257 test_bpf: add a schedule point
test_bpf() is taking 1.6 seconds nowadays, it is time
to add a schedule point in it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-26 21:06:56 +01:00
Matthew Wilcox
4b0ad07653 idr: Fix handling of IDs above INT_MAX
Khalid reported that the kernel selftests are currently failing:

selftests: test_bpf.sh
========================================
test_bpf: [FAIL]
not ok 1..8 selftests:  test_bpf.sh [FAIL]

He bisected it to 6ce711f275 ("idr: Make
1-based IDRs more efficient").

The root cause is doing a signed comparison in idr_alloc_u32() instead
of an unsigned comparison.  I went looking for any similar problems and
found a couple (which would each result in the failure to warn in two
situations that aren't supposed to happen).

I knocked up a few test-cases to prove that I was right and added them
to the test-suite.

Reported-by: Khalid Aziz <khalid.aziz@oracle.com>
Tested-by: Khalid Aziz <khalid.aziz@oracle.com>
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
2018-02-26 14:39:30 -05:00
Linus Torvalds
13f514bef1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk fixlet from Petr Mladek:
 "People expect to see the real pointer value for %px.

  Let's substitute '(null)' only for the other %p? format modifiers that
  need to deference the pointer"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
  vsprintf: avoid misleading "(null)" for %px
2018-02-23 14:57:20 -08:00
Miles Chen
af1da68684 dma-debug: fix memory leak in debug_dma_alloc_coherent
Marty reported a memory leakage introduced by commit 3aaabbf1c3
("lib/dma-debug.c: fix incorrect pfn calculation"). Fix it
by checking the virtual address before allocating the entry.

This patch also use virt_addr_valid() instead of virt_to_page()
to check if a virtual address is linear.

Fixes: 3aaabbf1 ("lib/dma-debug.c: fix incorrect pfn calculation")
Reported-by: Marty Faltesek <mfaltesek@google.com>
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-02-22 15:02:33 -08:00
Anders Roxell
908009e832 lib/Kconfig.debug: enable RUNTIME_TESTING_MENU
Commit d3deafaa8b ("lib/: make RUNTIME_TESTS a menuconfig to ease
disabling it all") causes a regression when using runtime tests due to
it defaults RUNTIME_TESTING_MENU to not set.

Link: http://lkml.kernel.org/r/20180214133015.10090-1-anders.roxell@linaro.org
Fixes: d3deafaa8b ("lib/: make RUNTIME_TESTS a menuconfig to easedisabling it all")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Cc: Vincent Legoll <vincent.legoll@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-21 15:35:43 -08:00
Rasmus Villemoes
b1a8a7a700 ida: do zeroing in ida_pre_get()
As far as I can tell, the only place the per-cpu ida_bitmap is populated
is in ida_pre_get.  The pre-allocated element is stolen in two places in
ida_get_new_above, in both cases immediately followed by a memset(0).

Since ida_get_new_above is called with locks held, do the zeroing in
ida_pre_get, or rather let kmalloc() do it.  Also, apparently gcc
generates ~44 bytes of code to do a memset(, 0, 128):

  $ scripts/bloat-o-meter vmlinux.{0,1}
  add/remove: 0/0 grow/shrink: 2/1 up/down: 5/-88 (-83)
  Function                                     old     new   delta
  ida_pre_get                                  115     119      +4
  vermagic                                      27      28      +1
  ida_get_new_above                            715     627     -88

Link: http://lkml.kernel.org/r/20180108225634.15340-1-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Eric Biggers <ebiggers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-21 15:35:43 -08:00
Christoph Hellwig
42ed64524d dma-direct: comment the dma_direct_free calling convention
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-02-12 15:59:07 +00:00
Christoph Hellwig
f25e6f6b4e dma-direct: mark as is_phys
Various PCI_DMA_BUS_IS_PHYS implementations rely on this flag to make proper
decisions for block and networking addressability.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-02-12 15:59:06 +00:00
Linus Torvalds
9a61df9e5f Kbuild updates for v4.16 (2nd)
Makefile changes:
 - enable unused-variable warning that was wrongly disabled for clang
 
 Kconfig changes:
 - warn blank 'help' and fix existing instances
 - fix 'choice' behavior to not write out invisible symbols
 - fix misc weirdness
 
 Coccinell changes:
 - fix false positive of free after managed memory alloc detection
 - improve performance of NULL dereference detection
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Merge tag 'kbuild-v4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:
 "Makefile changes:
   - enable unused-variable warning that was wrongly disabled for clang

  Kconfig changes:
   - warn about blank 'help' and fix existing instances
   - fix 'choice' behavior to not write out invisible symbols
   - fix misc weirdness

  Coccinell changes:
   - fix false positive of free after managed memory alloc detection
   - improve performance of NULL dereference detection"

* tag 'kbuild-v4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (21 commits)
  kconfig: remove const qualifier from sym_expand_string_value()
  kconfig: add xrealloc() helper
  kconfig: send error messages to stderr
  kconfig: echo stdin to stdout if either is redirected
  kconfig: remove check_stdin()
  kconfig: remove 'config*' pattern from .gitignnore
  kconfig: show '?' prompt even if no help text is available
  kconfig: do not write choice values when their dependency becomes n
  coccinelle: deref_null: avoid useless computation
  coccinelle: devm_free: reduce false positives
  kbuild: clang: disable unused variable warnings only when constant
  kconfig: Warn if help text is blank
  nios2: kconfig: Remove blank help text
  arm: vt8500: kconfig: Remove blank help text
  MIPS: kconfig: Remove blank help text
  MIPS: BCM63XX: kconfig: Remove blank help text
  lib/Kconfig.debug: Remove blank help text
  Staging: rtl8192e: kconfig: Remove blank help text
  Staging: rtl8192u: kconfig: Remove blank help text
  mmc: kconfig: Remove blank help text
  ...
2018-02-09 19:32:41 -08:00
Linus Torvalds
c839682c71 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Make allocations less aggressive in x_tables, from Minchal Hocko.

 2) Fix netfilter flowtable Kconfig deps, from Pablo Neira Ayuso.

 3) Fix connection loss problems in rtlwifi, from Larry Finger.

 4) Correct DRAM dump length for some chips in ath10k driver, from Yu
    Wang.

 5) Fix ABORT handling in rxrpc, from David Howells.

 6) Add SPDX tags to Sun networking drivers, from Shannon Nelson.

 7) Some ipv6 onlink handling fixes, from David Ahern.

 8) Netem packet scheduler interval calcualtion fix from Md. Islam.

 9) Don't put crypto buffers on-stack in rxrpc, from David Howells.

10) Fix handling of error non-delivery status in netlink multicast
    delivery over multiple namespaces, from Nicolas Dichtel.

11) Missing xdp flush in tuntap driver, from Jason Wang.

12) Synchonize RDS protocol netns/module teardown with rds object
    management, from Sowini Varadhan.

13) Add nospec annotations to mpls, from Dan Williams.

14) Fix SKB truesize handling in TIPC, from Hoang Le.

15) Interrupt masking fixes in stammc from Niklas Cassel.

16) Don't allow ptr_ring objects to be sized outside of kmalloc's
    limits, from Jason Wang.

17) Don't allow SCTP chunks to be built which will have a length
    exceeding the chunk header's 16-bit length field, from Alexey
    Kodanev.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (82 commits)
  ibmvnic: Remove skb->protocol checks in ibmvnic_xmit
  bpf: fix rlimit in reuseport net selftest
  sctp: verify size of a new chunk in _sctp_make_chunk()
  s390/qeth: fix SETIP command handling
  s390/qeth: fix underestimated count of buffer elements
  ptr_ring: try vmalloc() when kmalloc() fails
  ptr_ring: fail early if queue occupies more than KMALLOC_MAX_SIZE
  net: stmmac: remove redundant enable of PMT irq
  net: stmmac: rename GMAC_INT_DEFAULT_MASK for dwmac4
  net: stmmac: discard disabled flags in interrupt status register
  ibmvnic: Reset long term map ID counter
  tools/libbpf: handle issues with bpf ELF objects containing .eh_frames
  selftests/bpf: add selftest that use test_libbpf_open
  selftests/bpf: add test program for loading BPF ELF files
  tools/libbpf: improve the pr_debug statements to contain section numbers
  bpf: Sync kernel ABI header with tooling header for bpf_common.h
  net: phy: fix phy_start to consider PHY_IGNORE_INTERRUPT
  net: thunder: change q_len's type to handle max ring size
  tipc: fix skb truesize/datasize ratio control
  net/sched: cls_u32: fix cls_u32 on filter replace
  ...
2018-02-09 15:34:18 -08:00
David S. Miller
437a4db66d Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-02-09

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Two fixes for BPF sockmap in order to break up circular map references
   from programs attached to sockmap, and detaching related sockets in
   case of socket close() event. For the latter we get rid of the
   smap_state_change() and plug into ULP infrastructure, which will later
   also be used for additional features anyway such as TX hooks. For the
   second issue, dependency chain is broken up via map release callback
   to free parse/verdict programs, all from John.

2) Fix a libbpf relocation issue that was found while implementing XDP
   support for Suricata project. Issue was that when clang was invoked
   with default target instead of bpf target, then various other e.g.
   debugging relevant sections are added to the ELF file that contained
   relocation entries pointing to non-BPF related sections which libbpf
   trips over instead of skipping them. Test cases for libbpf are added
   as well, from Jesper.

3) Various misc fixes for bpftool and one for libbpf: a small addition
   to libbpf to make sure it recognizes all standard section prefixes.
   Then, the Makefile in bpftool/Documentation is improved to explicitly
   check for rst2man being installed on the system as we otherwise risk
   installing empty man pages; the man page for bpftool-map is corrected
   and a set of missing bash completions added in order to avoid shipping
   bpftool where the completions are only partially working, from Quentin.

4) Fix applying the relocation to immediate load instructions in the
   nfp JIT which were missing a shift, from Jakub.

5) Two fixes for the BPF kernel selftests: handle CONFIG_BPF_JIT_ALWAYS_ON=y
   gracefully in test_bpf.ko module and mark them as FLAG_EXPECTED_FAIL
   in this case; and explicitly delete the veth devices in the two tests
   test_xdp_{meta,redirect}.sh before dismantling the netnses as when
   selftests are run in batch mode, then workqueue to handle destruction
   might not have finished yet and thus veth creation in next test under
   same dev name would fail, from Yonghong.

6) Fix test_kmod.sh to check the test_bpf.ko module path before performing
   an insmod, and fallback to modprobe. Especially the latter is useful
   when having a device under test that has the modules installed instead,
   from Naresh.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-09 14:05:10 -05:00
Linus Torvalds
9d21874da8 Merge branch 'idr-2018-02-06' of git://git.infradead.org/users/willy/linux-dax
Pull idr updates from Matthew Wilcox:

 - test-suite improvements

 - replace the extended API by improving the normal API

 - performance improvement for IDRs which are 1-based rather than
   0-based

 - add documentation

* 'idr-2018-02-06' of git://git.infradead.org/users/willy/linux-dax:
  idr: Add documentation
  idr: Make 1-based IDRs more efficient
  idr: Warn if old iterators see large IDs
  idr: Rename idr_for_each_entry_ext
  idr: Remove idr_alloc_ext
  cls_u32: Convert to idr_alloc_u32
  cls_u32: Reinstate cyclic allocation
  cls_flower: Convert to idr_alloc_u32
  cls_bpf: Convert to use idr_alloc_u32
  cls_basic: Convert to use idr_alloc_u32
  cls_api: Convert to idr_alloc_u32
  net sched actions: Convert to use idr_alloc_u32
  idr: Add idr_alloc_u32 helper
  idr: Delete idr_find_ext function
  idr: Delete idr_replace_ext function
  idr: Delete idr_remove_ext function
  IDR test suite: Check handling negative end correctly
  idr test suite: Fix ida_test_random()
  radix tree test suite: Remove ARRAY_SIZE
2018-02-08 14:39:29 -08:00
Adam Borowski
3a129cc215 vsprintf: avoid misleading "(null)" for %px
Like %pK already does, print "00000000" instead.

This confused people -- the convention is that "(null)" means you tried to
dereference a null pointer as opposed to printing the address.

Link: http://lkml.kernel.org/r/20180204174521.21383-1-kilobyte@angband.pl
To: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
To: Steven Rostedt <rostedt@goodmis.org>
To: linux-kernel@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Roberts, William C" <william.c.roberts@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-08 14:21:41 +01:00
Linus Torvalds
a2e5790d84 Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:

 - kasan updates

 - procfs

 - lib/bitmap updates

 - other lib/ updates

 - checkpatch tweaks

 - rapidio

 - ubsan

 - pipe fixes and cleanups

 - lots of other misc bits

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits)
  Documentation/sysctl/user.txt: fix typo
  MAINTAINERS: update ARM/QUALCOMM SUPPORT patterns
  MAINTAINERS: update various PALM patterns
  MAINTAINERS: update "ARM/OXNAS platform support" patterns
  MAINTAINERS: update Cortina/Gemini patterns
  MAINTAINERS: remove ARM/CLKDEV SUPPORT file pattern
  MAINTAINERS: remove ANDROID ION pattern
  mm: docs: add blank lines to silence sphinx "Unexpected indentation" errors
  mm: docs: fix parameter names mismatch
  mm: docs: fixup punctuation
  pipe: read buffer limits atomically
  pipe: simplify round_pipe_size()
  pipe: reject F_SETPIPE_SZ with size over UINT_MAX
  pipe: fix off-by-one error when checking buffer limits
  pipe: actually allow root to exceed the pipe buffer limits
  pipe, sysctl: remove pipe_proc_fn()
  pipe, sysctl: drop 'min' parameter from pipe-max-size converter
  kasan: rework Kconfig settings
  crash_dump: is_kdump_kernel can be boolean
  kernel/mutex: mutex_is_locked can be boolean
  ...
2018-02-06 22:15:42 -08:00
Arnd Bergmann
e7c52b84fb kasan: rework Kconfig settings
We get a lot of very large stack frames using gcc-7.0.1 with the default
-fsanitize-address-use-after-scope --param asan-stack=1 options, which can
easily cause an overflow of the kernel stack, e.g.

  drivers/gpu/drm/i915/gvt/handlers.c:2434:1: warning: the frame size of 46176 bytes is larger than 3072 bytes
  drivers/net/wireless/ralink/rt2x00/rt2800lib.c:5650:1: warning: the frame size of 23632 bytes is larger than 3072 bytes
  lib/atomic64_test.c:250:1: warning: the frame size of 11200 bytes is larger than 3072 bytes
  drivers/gpu/drm/i915/gvt/handlers.c:2621:1: warning: the frame size of 9208 bytes is larger than 3072 bytes
  drivers/media/dvb-frontends/stv090x.c:3431:1: warning: the frame size of 6816 bytes is larger than 3072 bytes
  fs/fscache/stats.c:287:1: warning: the frame size of 6536 bytes is larger than 3072 bytes

To reduce this risk, -fsanitize-address-use-after-scope is now split out
into a separate CONFIG_KASAN_EXTRA Kconfig option, leading to stack
frames that are smaller than 2 kilobytes most of the time on x86_64.  An
earlier version of this patch also prevented combining KASAN_EXTRA with
KASAN_INLINE, but that is no longer necessary with gcc-7.0.1.

All patches to get the frame size below 2048 bytes with CONFIG_KASAN=y
and CONFIG_KASAN_EXTRA=n have been merged by maintainers now, so we can
bring back that default now.  KASAN_EXTRA=y still causes lots of
warnings but now defaults to !COMPILE_TEST to disable it in
allmodconfig, and it remains disabled in all other defconfigs since it
is a new option.  I arbitrarily raise the warning limit for KASAN_EXTRA
to 3072 to reduce the noise, but an allmodconfig kernel still has around
50 warnings on gcc-7.

I experimented a bit more with smaller stack frames and have another
follow-up series that reduces the warning limit for 64-bit architectures
to 1280 bytes (without CONFIG_KASAN).

With earlier versions of this patch series, I also had patches to address
the warnings we get with KASAN and/or KASAN_EXTRA, using a
"noinline_if_stackbloat" annotation.

That annotation now got replaced with a gcc-8 bugfix (see
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715) and a workaround for
older compilers, which means that KASAN_EXTRA is now just as bad as
before and will lead to an instant stack overflow in a few extreme
cases.

This reverts parts of commit 3f181b4d86 ("lib/Kconfig.debug: disable
-Wframe-larger-than warnings with KASAN=y").  Two patches in linux-next
should be merged first to avoid introducing warnings in an allmodconfig
build:
  3cd890dbe2 ("media: dvb-frontends: fix i2c access helpers for KASAN")
  16c3ada89c ("media: r820t: fix r820t_write_reg for KASAN")

Do we really need to backport this?

I think we do: without this patch, enabling KASAN will lead to
unavoidable kernel stack overflow in certain device drivers when built
with gcc-7 or higher on linux-4.10+ or any version that contains a
backport of commit c5caf21ab0.  Most people are probably still on
older compilers, but it will get worse over time as they upgrade their
distros.

The warnings we get on kernels older than this should all be for code
that uses dangerously large stack frames, though most of them do not
cause an actual stack overflow by themselves.The asan-stack option was
added in linux-4.0, and commit 3f181b4d86 ("lib/Kconfig.debug:
disable -Wframe-larger-than warnings with KASAN=y") effectively turned
off the warning for allmodconfig kernels, so I would like to see this
fix backported to any kernels later than 4.0.

I have done dozens of fixes for individual functions with stack frames
larger than 2048 bytes with asan-stack, and I plan to make sure that
all those fixes make it into the stable kernels as well (most are
already there).

Part of the complication here is that asan-stack (from 4.0) was
originally assumed to always require much larger stacks, but that
turned out to be a combination of multiple gcc bugs that we have now
worked around and fixed, but sanitize-address-use-after-scope (from
v4.10) has a much higher inherent stack usage and also suffers from at
least three other problems that we have analyzed but not yet fixed
upstream, each of them makes the stack usage more severe than it should
be.

Link: http://lkml.kernel.org/r/20171221134744.2295529-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:47 -08:00
Andrey Ryabinin
bac7a1fff7 lib/ubsan: remove returns-nonnull-attribute checks
Similarly to type mismatch checks, new GCC 8.x and Clang also changed for
ABI for returns_nonnull checks.  While we can update our code to conform
the new ABI it's more reasonable to just remove it.  Because it's just
dead code, we don't have any single user of returns_nonnull attribute in
the whole kernel.

And AFAIU the advantage that this attribute could bring would be mitigated
by -fno-delete-null-pointer-checks cflag that we use to build the kernel.
So it's unlikely we will have a lot of returns_nonnull attribute in
future.

So let's just remove the code, it has no use.

[aryabinin@virtuozzo.com: fix warning]
  Link: http://lkml.kernel.org/r/20180122165711.11510-1-aryabinin@virtuozzo.com
Link: http://lkml.kernel.org/r/20180119152853.16806-2-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Sodagudi Prasad <psodagud@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:46 -08:00
Andrey Ryabinin
42440c1f99 lib/ubsan: add type mismatch handler for new GCC/Clang
UBSAN=y fails to build with new GCC/clang:

    arch/x86/kernel/head64.o: In function `sanitize_boot_params':
    arch/x86/include/asm/bootparam_utils.h:37: undefined reference to `__ubsan_handle_type_mismatch_v1'

because Clang and GCC 8 slightly changed ABI for 'type mismatch' errors.
Compiler now uses new __ubsan_handle_type_mismatch_v1() function with
slightly modified 'struct type_mismatch_data'.

Let's add new 'struct type_mismatch_data_common' which is independent from
compiler's layout of 'struct type_mismatch_data'.  And make
__ubsan_handle_type_mismatch[_v1]() functions transform compiler-dependent
type mismatch data to our internal representation.  This way, we can
support both old and new compilers with minimal amount of change.

Link: http://lkml.kernel.org/r/20180119152853.16806-1-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reported-by: Sodagudi Prasad <psodagud@codeaurora.org>
Cc: <stable@vger.kernel.org>	[4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:46 -08:00
Andrew Morton
b8fe1120b4 lib/ubsan.c: s/missaligned/misaligned/
A vist from the spelling fairy.

Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:46 -08:00
Pravin Shedge
92fc7cb8ae lib/test_sort.c: add module unload support
test_sort.c performs array-based and linked list sort test.  Code allows
to compile either as a loadable modules or builtin into the kernel.

Current code is not allow to unload the test_sort.ko module after
successful completion.

This patch adds support to unload the "test_sort.ko" module by adding
module_exit support.

Previous patch was implemented auto unload support by returning -EAGAIN
from module_init() function on successful case, but this approach is not
ideal.

The auto-unload might seem like a nice optimization, but it encourages
inconsistent behaviour.  And behaviour that is different from all other
normal modules.

Link: http://lkml.kernel.org/r/1513967133-6843-1-git-send-email-pravin.shedge4linux@gmail.com
Signed-off-by: Pravin Shedge <pravin.shedge4linux@gmail.com>
Cc: Kostenzer Felix <fkostenzer@live.at>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:45 -08:00
Vincent Legoll
d3deafaa8b lib/: make RUNTIME_TESTS a menuconfig to ease disabling it all
No need to get into the submenu to disable all related config entries.

This makes it easier to disable all RUNTIME_TESTS config options without
entering the submenu.  It will also enable one to see that en/dis-abled
state from the outside menu.

This is only intended to change menuconfig UI, not change the config
dependencies.

Link: http://lkml.kernel.org/r/20171209162742.7363-1-vincent.legoll@gmail.com
Signed-off-by: Vincent Legoll <vincent.legoll@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:44 -08:00
Clement Courbet
0ade34c370 lib: optimize cpumask_next_and()
We've measured that we spend ~0.6% of sys cpu time in cpumask_next_and().
It's essentially a joined iteration in search for a non-zero bit, which is
currently implemented as a lookup join (find a nonzero bit on the lhs,
lookup the rhs to see if it's set there).

Implement a direct join (find a nonzero bit on the incrementally built
join).  Also add generic bitmap benchmarks in the new `test_find_bit`
module for new function (see `find_next_and_bit` in [2] and [3] below).

For cpumask_next_and, direct benchmarking shows that it's 1.17x to 14x
faster with a geometric mean of 2.1 on 32 CPUs [1].  No impact on memory
usage.  Note that on Arm, the new pure-C implementation still outperforms
the old one that uses a mix of C and asm (`find_next_bit`) [3].

[1] Approximate benchmark code:

```
  unsigned long src1p[nr_cpumask_longs] = {pattern1};
  unsigned long src2p[nr_cpumask_longs] = {pattern2};
  for (/*a bunch of repetitions*/) {
    for (int n = -1; n <= nr_cpu_ids; ++n) {
      asm volatile("" : "+rm"(src1p)); // prevent any optimization
      asm volatile("" : "+rm"(src2p));
      unsigned long result = cpumask_next_and(n, src1p, src2p);
      asm volatile("" : "+rm"(result));
    }
  }
```

Results:
pattern1    pattern2     time_before/time_after
0x0000ffff  0x0000ffff   1.65
0x0000ffff  0x00005555   2.24
0x0000ffff  0x00001111   2.94
0x0000ffff  0x00000000   14.0
0x00005555  0x0000ffff   1.67
0x00005555  0x00005555   1.71
0x00005555  0x00001111   1.90
0x00005555  0x00000000   6.58
0x00001111  0x0000ffff   1.46
0x00001111  0x00005555   1.49
0x00001111  0x00001111   1.45
0x00001111  0x00000000   3.10
0x00000000  0x0000ffff   1.18
0x00000000  0x00005555   1.18
0x00000000  0x00001111   1.17
0x00000000  0x00000000   1.25
-----------------------------
               geo.mean  2.06

[2] test_find_next_bit, X86 (skylake)

 [ 3913.477422] Start testing find_bit() with random-filled bitmap
 [ 3913.477847] find_next_bit: 160868 cycles, 16484 iterations
 [ 3913.477933] find_next_zero_bit: 169542 cycles, 16285 iterations
 [ 3913.478036] find_last_bit: 201638 cycles, 16483 iterations
 [ 3913.480214] find_first_bit: 4353244 cycles, 16484 iterations
 [ 3913.480216] Start testing find_next_and_bit() with random-filled
 bitmap
 [ 3913.481074] find_next_and_bit: 89604 cycles, 8216 iterations
 [ 3913.481075] Start testing find_bit() with sparse bitmap
 [ 3913.481078] find_next_bit: 2536 cycles, 66 iterations
 [ 3913.481252] find_next_zero_bit: 344404 cycles, 32703 iterations
 [ 3913.481255] find_last_bit: 2006 cycles, 66 iterations
 [ 3913.481265] find_first_bit: 17488 cycles, 66 iterations
 [ 3913.481266] Start testing find_next_and_bit() with sparse bitmap
 [ 3913.481272] find_next_and_bit: 764 cycles, 1 iterations

[3] test_find_next_bit, arm (v7 odroid XU3).

[  267.206928] Start testing find_bit() with random-filled bitmap
[  267.214752] find_next_bit: 4474 cycles, 16419 iterations
[  267.221850] find_next_zero_bit: 5976 cycles, 16350 iterations
[  267.229294] find_last_bit: 4209 cycles, 16419 iterations
[  267.279131] find_first_bit: 1032991 cycles, 16420 iterations
[  267.286265] Start testing find_next_and_bit() with random-filled
bitmap
[  267.302386] find_next_and_bit: 2290 cycles, 8140 iterations
[  267.309422] Start testing find_bit() with sparse bitmap
[  267.316054] find_next_bit: 191 cycles, 66 iterations
[  267.322726] find_next_zero_bit: 8758 cycles, 32703 iterations
[  267.329803] find_last_bit: 84 cycles, 66 iterations
[  267.336169] find_first_bit: 4118 cycles, 66 iterations
[  267.342627] Start testing find_next_and_bit() with sparse bitmap
[  267.356919] find_next_and_bit: 91 cycles, 1 iterations

[courbet@google.com: v6]
  Link: http://lkml.kernel.org/r/20171129095715.23430-1-courbet@google.com
[geert@linux-m68k.org: m68k/bitops: always include <asm-generic/bitops/find.h>]
  Link: http://lkml.kernel.org/r/1512556816-28627-1-git-send-email-geert@linux-m68k.org
Link: http://lkml.kernel.org/r/20171128131334.23491-1-courbet@google.com
Signed-off-by: Clement Courbet <courbet@google.com>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Yury Norov <ynorov@caviumnetworks.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:44 -08:00
Yury Norov
15ff67bf85 lib/find_bit_benchmark.c: improvements
As suggested in review comments:
* printk: align numbers using whitespaces instead of tabs;
* return error value from init() to avoid calling rmmod if testing again;
* use ktime_get instead of get_cycles as some arches don't support it;

The output in dmesg (on QEMU arm64):
[   38.823430] Start testing find_bit() with random-filled bitmap
[   38.845358] find_next_bit:                20138448 ns, 163968 iterations
[   38.856217] find_next_zero_bit:           10615328 ns, 163713 iterations
[   38.863564] find_last_bit:                 7111888 ns, 163967 iterations
[   40.944796] find_first_bit:             2081007216 ns, 163968 iterations
[   40.944975]
[   40.944975] Start testing find_bit() with sparse bitmap
[   40.945268] find_next_bit:                   73216 ns,    656 iterations
[   40.967858] find_next_zero_bit:           22461008 ns, 327025 iterations
[   40.968047] find_last_bit:                   62320 ns,    656 iterations
[   40.978060] find_first_bit:                9889360 ns,    656 iterations

Link: http://lkml.kernel.org/r/20171124143040.a44jvhmnaiyedg2i@yury-thinkpad
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Clement Courbet <courbet@google.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:44 -08:00
Yury Norov
dceeb3e7fd lib/test_find_bit.c: rename to find_bit_benchmark.c
As suggested in review comments, rename test_find_bit.c to
find_bit_benchmark.c.

Link: http://lkml.kernel.org/r/20171124143040.a44jvhmnaiyedg2i@yury-thinkpad
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Clement Courbet <courbet@google.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:44 -08:00
Alexander Potapenko
a571b272ab lib/stackdepot.c: use a non-instrumented version of memcmp()
stackdepot used to call memcmp(), which compiler tools normally
instrument, therefore every lookup used to unnecessarily call instrumented
code.  This is somewhat ok in the case of KASAN, but under KMSAN a lot of
time was spent in the instrumentation.

Link: http://lkml.kernel.org/r/20171117172149.69562-1-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:44 -08:00
Andy Shevchenko
fe81814c3e lib/test_bitmap.c: clean up test_zero_fill_copy() test case and rename
Since we have separate explicit test cases for bitmap_zero() /
bitmap_clear() and bitmap_fill() / bitmap_set(), clean up
test_zero_fill_copy() to only test bitmap_copy() functionality and thus
rename a function to reflect the changes.

While here, replace bitmap_fill() by bitmap_set() with proper values.

Link: http://lkml.kernel.org/r/20180109172430.87452-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Yury Norov <ynorov@caviumnetworks.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:44 -08:00
Andy Shevchenko
978f369c5c lib/test_bitmap.c: add bitmap_fill()/bitmap_set() test cases
Explicitly test bitmap_fill() and bitmap_set() functions.

For bitmap_fill() we expect a consistent behaviour as in bitmap_zero(),
i.e.  the trailing bits will be set up to unsigned long boundary.

Link: http://lkml.kernel.org/r/20180109172430.87452-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Yury Norov <ynorov@caviumnetworks.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:44 -08:00
Andy Shevchenko
ee3527bd5e lib/test_bitmap.c: add bitmap_zero()/bitmap_clear() test cases
Explicitly test bitmap_zero() and bitmap_clear() functions.

Link: http://lkml.kernel.org/r/20180109172430.87452-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Yury Norov <ynorov@caviumnetworks.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:44 -08:00
Yury Norov
3aa56885e5 bitmap: replace bitmap_{from,to}_u32array
with bitmap_{from,to}_arr32 over the kernel. Additionally to it:
* __check_eq_bitmap() now takes single nbits argument.
* __check_eq_u32_array is not used in new test but may be used in
  future. So I don't remove it here, but annotate as __used.

Tested on arm64 and 32-bit BE mips.

[arnd@arndb.de: perf: arm_dsu_pmu: convert to bitmap_from_arr32]
  Link: http://lkml.kernel.org/r/20180201172508.5739-2-ynorov@caviumnetworks.com
[ynorov@caviumnetworks.com: fix net/core/ethtool.c]
  Link: http://lkml.kernel.org/r/20180205071747.4ekxtsbgxkj5b2fz@yury-thinkpad
Link: http://lkml.kernel.org/r/20171228150019.27953-2-ynorov@caviumnetworks.com
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: David Decotigny <decot@googlers.com>,
Cc: David S. Miller <davem@davemloft.net>,
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:44 -08:00
Yury Norov
c724f19361 bitmap: new bitmap_copy_safe and bitmap_{from,to}_arr32
This patchset replaces bitmap_{to,from}_u32array with more simple and
standard looking copy-like functions.

bitmap_from_u32array() takes 4 arguments (bitmap_to_u32array is similar):
 - unsigned long *bitmap, which is destination;
 - unsigned int nbits, the length of destination bitmap, in bits;
 - const u32 *buf, the source; and
 - unsigned int nwords, the length of source buffer in ints.

In description to the function it is detailed like:
* copy min(nbits, 32*nwords) bits from @buf to @bitmap, remaining
* bits between nword and nbits in @bitmap (if any) are cleared.

Having two size arguments looks unneeded and potentially dangerous.

It is unneeded because normally user of copy-like function should take
care of the size of destination and make it big enough to fit source
data.

And it is dangerous because function may hide possible error if user
doesn't provide big enough bitmap, and data becomes silently dropped.

That's why all copy-like functions have 1 argument for size of copying
data, and I don't see any reason to make bitmap_from_u32array()
different.

One exception that comes in mind is strncpy() which also provides size
of destination in arguments, but it's strongly argued by the possibility
of taking broken strings in source.  This is not the case of
bitmap_{from,to}_u32array().

There is no many real users of bitmap_{from,to}_u32array(), and they all
very clearly provide size of destination matched with the size of
source, so additional functionality is not used in fact. Like this:
bitmap_from_u32array(to->link_modes.supported,
		__ETHTOOL_LINK_MODE_MASK_NBITS,
		link_usettings.link_modes.supported,
		__ETHTOOL_LINK_MODE_MASK_NU32);
Where:
#define __ETHTOOL_LINK_MODE_MASK_NU32 \
	DIV_ROUND_UP(__ETHTOOL_LINK_MODE_MASK_NBITS, 32)

In this patch, bitmap_copy_safe and bitmap_{from,to}_arr32 are introduced.

'Safe' in bitmap_copy_safe() stands for clearing unused bits in bitmap
beyond last bit till the end of last word. It is useful for hardening
API when bitmap is assumed to be exposed to userspace.

bitmap_{from,to}_arr32 functions are replacements for
bitmap_{from,to}_u32array. They don't take unneeded nwords argument, and
so simpler in implementation and understanding.

This patch suggests optimization for 32-bit systems - aliasing
bitmap_{from,to}_arr32 to bitmap_copy_safe.

Other possible optimization is aliasing 64-bit LE bitmap_{from,to}_arr32 to
more generic function(s). But I didn't end up with the function that would
be helpful by itself, and can be used to alias 64-bit LE
bitmap_{from,to}_arr32, like bitmap_copy_safe() does. So I preferred to
leave things as is.

The following patch switches kernel to new API and introduces test for it.

Discussion is here: https://lkml.org/lkml/2017/11/15/592

[ynorov@caviumnetworks.com: rename bitmap_copy_safe to bitmap_copy_clear_tail]
  Link: http://lkml.kernel.org/r/20180201172508.5739-3-ynorov@caviumnetworks.com
Link: http://lkml.kernel.org/r/20171228150019.27953-1-ynorov@caviumnetworks.com
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: David Decotigny <decot@googlers.com>,
Cc: David S. Miller <davem@davemloft.net>,
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:44 -08:00
Colin Ian King
48c2323954 kasan: remove redundant initialization of variable 'real_size'
Variable real_size is initialized with a value that is never read, it is
re-assigned a new value later on, hence the initialization is redundant
and can be removed.

Cleans up clang warning:

  lib/test_kasan.c:422:21: warning: Value stored to 'real_size' during its initialization is never read

Link: http://lkml.kernel.org/r/20180206144950.32457-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:43 -08:00
Dmitry Vyukov
b1d5728939 kasan: detect invalid frees
Detect frees of pointers into middle of heap objects.

Link: http://lkml.kernel.org/r/cb569193190356beb018a03bb8d6fbae67e7adbc.1514378558.git.dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>a
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:43 -08:00
Dmitry Vyukov
47adccce3e kasan: detect invalid frees for large objects
Patch series "kasan: detect invalid frees".

KASAN detects double-frees, but does not detect invalid-frees (when a
pointer into a middle of heap object is passed to free).  We recently had
a very unpleasant case in crypto code which freed an inner object inside
of a heap allocation.  This left unnoticed during free, but totally
corrupted heap and later lead to a bunch of random crashes all over kernel
code.

Detect invalid frees.

This patch (of 5):

Detect frees of pointers into middle of large heap objects.

I dropped const from kasan_kfree_large() because it starts propagating
through a bunch of functions in kasan_report.c, slab/slub nearest_obj(),
all of their local variables, fixup_red_left(), etc.

Link: http://lkml.kernel.org/r/1b45b4fe1d20fc0de1329aab674c1dd973fee723.1514378558.git.dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>a
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:42 -08:00
Paul Lawrence
00a14294bb kasan: add tests for alloca poisoning
Link: http://lkml.kernel.org/r/20171204191735.132544-5-paullawrence@google.com
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Paul Lawrence <paullawrence@google.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:42 -08:00
Matthew Wilcox
6ce711f275 idr: Make 1-based IDRs more efficient
About 20% of the IDR users in the kernel want the allocated IDs to start
at 1.  The implementation currently searches all the way down the left
hand side of the tree, finds no free ID other than ID 0, walks all the
way back up, and then all the way down again.  This patch 'rebases' the
ID so we fill the entire radix tree, rather than leave a gap at 0.

Chris Wilson says: "I did the quick hack of allocating index 0 of the
idr and that eradicated idr_get_free() from being at the top of the
profiles for the many-object stress tests. This improvement will be
much appreciated."

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
2018-02-06 16:41:29 -05:00