openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity
809,785 Commits 18 Branches 27 Tags 3.4 GiB
Commit Graph

29336 Commits

Author SHA1 Message Date
Yonghong Song 17e3ac8125 bpf: fix bpffs bitfield pretty print 
Commit 9d5f9f701b ("bpf: btf: fix struct/union/fwd types
with kind_flag") introduced kind_flag and used bitfield_size
in the btf_member to directly pretty print member values.

The commit contained a bug where the incorrect parameters could be
passed to function btf_bitfield_seq_show(). The bits_offset
parameter in the function expects a value less than 8.
Instead, the member offset in the structure is passed.

The below is btf_bitfield_seq_show() func signature:
  void btf_bitfield_seq_show(void *data, u8 bits_offset,
                             u8 nr_bits, struct seq_file *m)
both bits_offset and nr_bits are u8 type. If the bitfield
member offset is greater than 256, incorrect value will
be printed.

This patch fixed the issue by calculating correct proper
data offset and bits_offset similar to non kind_flag case.

Fixes: 9d5f9f701b ("bpf: btf: fix struct/union/fwd types with kind_flag")
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
 2019-01-11 10:40:54 +01:00
Song Liu beaf3d1901 bpf: fix panic in stack_map_get_build_id() on i386 and arm32 
As Naresh reported, test_stacktrace_build_id() causes panic on i386 and
arm32 systems. This is caused by page_address() returns NULL in certain
cases.

This patch fixes this error by using kmap_atomic/kunmap_atomic instead
of page_address.

Fixes: 615755a77b (" bpf: extend stackmap to save binary_build_id+offset instead of address")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
 2019-01-10 16:02:17 +01:00
Daniel Borkmann d3bd7413e0 bpf: fix sanitation of alu op with pointer / scalar type from different paths 
While 979d63d50c ("bpf: prevent out of bounds speculation on pointer
arithmetic") took care of rejecting alu op on pointer when e.g. pointer
came from two different map values with different map properties such as
value size, Jann reported that a case was not covered yet when a given
alu op is used in both "ptr_reg += reg" and "numeric_reg += reg" from
different branches where we would incorrectly try to sanitize based
on the pointer's limit. Catch this corner case and reject the program
instead.

Fixes: 979d63d50c ("bpf: prevent out of bounds speculation on pointer arithmetic")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
 2019-01-05 21:32:38 -08:00
Linus Torvalds 96d4f267e4 Remove 'type' argument from access_ok() function 
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2019-01-03 18:57:57 -08:00
Linus Torvalds 43d86ee8c6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 
Pull networking fixes from David Miller:
 "Several fixes here. Basically split down the line between newly
  introduced regressions and long existing problems:

   1) Double free in tipc_enable_bearer(), from Cong Wang.

   2) Many fixes to nf_conncount, from Florian Westphal.

   3) op->get_regs_len() can throw an error, check it, from Yunsheng
      Lin.

   4) Need to use GFP_ATOMIC in *_add_hash_mac_address() of fsl/fman
      driver, from Scott Wood.

   5) Inifnite loop in fib_empty_table(), from Yue Haibing.

   6) Use after free in ax25_fillin_cb(), from Cong Wang.

   7) Fix socket locking in nr_find_socket(), also from Cong Wang.

   8) Fix WoL wakeup enable in r8169, from Heiner Kallweit.

   9) On 32-bit sock->sk_stamp is not thread-safe, from Deepa Dinamani.

  10) Fix ptr_ring wrap during queue swap, from Cong Wang.

  11) Missing shutdown callback in hinic driver, from Xue Chaojing.

  12) Need to return NULL on error from ip6_neigh_lookup(), from Stefano
      Brivio.

  13) BPF out of bounds speculation fixes from Daniel Borkmann"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (57 commits)
  ipv6: Consider sk_bound_dev_if when binding a socket to an address
  ipv6: Fix dump of specific table with strict checking
  bpf: add various test cases to selftests
  bpf: prevent out of bounds speculation on pointer arithmetic
  bpf: fix check_map_access smin_value test when pointer contains offset
  bpf: restrict unknown scalars of mixed signed bounds for unprivileged
  bpf: restrict stack pointer arithmetic for unprivileged
  bpf: restrict map value pointer arithmetic for unprivileged
  bpf: enable access to ax register also from verifier rewrite
  bpf: move tmp variable into ax register in interpreter
  bpf: move {prev_,}insn_idx into verifier env
  isdn: fix kernel-infoleak in capi_unlocked_ioctl
  ipv6: route: Fix return value of ip6_neigh_lookup() on neigh_create() error
  net/hamradio/6pack: use mod_timer() to rearm timers
  net-next/hinic:add shutdown callback
  net: hns3: call hns3_nic_net_open() while doing HNAE3_UP_CLIENT
  ip: validate header length on virtual device xmit
  tap: call skb_probe_transport_header after setting skb->dev
  ptr_ring: wrap back ->producer in __ptr_ring_swap_queue()
  net: rds: remove unnecessary NULL check
  ...
 2019-01-03 12:53:47 -08:00
Linus Torvalds e6b9257280 NFS client updates for Linux 4.21 
Note that there is a conflict with the rdma tree in this pull request, since
 we delete a file that has been changed in the rdma tree.  Hopefully that's
 easy enough to resolve!
 
 We also were unable to track down a maintainer for Neil Brown's changes to
 the generic cred code that are prerequisites to his RPC cred cleanup patches.
 We've been asking around for several months without any response, so
 hopefully it's okay to include those patches in this pull request.
 
 Stable bugfixes:
 - xprtrdma: Yet another double DMA-unmap # v4.20
 
 Features:
 - Allow some /proc/sys/sunrpc entries without CONFIG_SUNRPC_DEBUG
 - Per-xprt rdma receive workqueues
 - Drop support for FMR memory registration
 - Make port= mount option optional for RDMA mounts
 
 Other bugfixes and cleanups:
 - Remove unused nfs4_xdev_fs_type declaration
 - Fix comments for behavior that has changed
 - Remove generic RPC credentials by switching to 'struct cred'
 - Fix crossing mountpoints with different auth flavors
 - Various xprtrdma fixes from testing and auditing the close code
 - Fixes for disconnect issues when using xprtrdma with krb5
 - Clean up and improve xprtrdma trace points
 - Fix NFS v4.2 async copy reboot recovery
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEnZ5MQTpR7cLU7KEp18tUv7ClQOsFAlwtO50ACgkQ18tUv7Cl
 QOtZWQ//e5Hhp2TnQZ6U+99YKedjwBHP6psH3GKSEdeHSNdlSpZ5ckgHxvMb9TBa
 6t4ecgv5P/uYLIePQ0u2ubUFc9+TlyGi7Iacx13/YhK7kihGHDPnZhfl0QbYixV7
 rwa9bFcKmOrXs8ld+Hw3P2UL22G1gMf/LHDhPNshbW7LFZmcshKz+mKTk70kwkq9
 v7tFC59p6GwV8Sr2YI2NXn2fOWsUS00sQfgj2jceJYJ8PsNa+wHYF4wPj2IY5NsE
 D5Oq2kLPbytBhCllOHgopNZaf4qb5BfqhVETyc1O+kDF3BZKUhQ1PoDi2FPinaHM
 5/d8hS+5fr3eMBsQrPWQLXYjWQFUXnkQQJvU3Bo52AIgomsk/8uBq3FvH7XmFcBd
 C8sgnuUAkAS8feMes8GCS50BTxclnGuYGdyFJyCRXoG9Kn9rMrw9EKitky6EVq0v
 NmXhW79jK84a3yDXVlAIpZ8Y9BU/HQ3GviGX8lQEdZU9YiYRzDIHvpMFwzMgqaBi
 XvLbr8PlLOm8GZokThS8QYT/G2Wu6IwfUq/AufVjVD4+HiL3duKKfWSGAvcm6aAa
 GoRF6UG+OmjWlzKojtRc1dI+sy22Fzh+DW+Mx6tuf/b/66wkmYnW7eKcV4rt6Tm5
 /JEhvTMo9q7elL/4FgCoMCcdoc5eXqQyXRXrQiOU7YHLzn2aWU0=
 =DvVW
 -----END PGP SIGNATURE-----

Merge tag 'nfs-for-4.21-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client updates from Anna Schumaker:
 "Stable bugfixes:
   - xprtrdma: Yet another double DMA-unmap # v4.20

  Features:
   - Allow some /proc/sys/sunrpc entries without CONFIG_SUNRPC_DEBUG
   - Per-xprt rdma receive workqueues
   - Drop support for FMR memory registration
   - Make port= mount option optional for RDMA mounts

  Other bugfixes and cleanups:
   - Remove unused nfs4_xdev_fs_type declaration
   - Fix comments for behavior that has changed
   - Remove generic RPC credentials by switching to 'struct cred'
   - Fix crossing mountpoints with different auth flavors
   - Various xprtrdma fixes from testing and auditing the close code
   - Fixes for disconnect issues when using xprtrdma with krb5
   - Clean up and improve xprtrdma trace points
   - Fix NFS v4.2 async copy reboot recovery"

* tag 'nfs-for-4.21-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (63 commits)
  sunrpc: convert to DEFINE_SHOW_ATTRIBUTE
  sunrpc: Add xprt after nfs4_test_session_trunk()
  sunrpc: convert unnecessary GFP_ATOMIC to GFP_NOFS
  sunrpc: handle ENOMEM in rpcb_getport_async
  NFS: remove unnecessary test for IS_ERR(cred)
  xprtrdma: Prevent leak of rpcrdma_rep objects
  NFSv4.2 fix async copy reboot recovery
  xprtrdma: Don't leak freed MRs
  xprtrdma: Add documenting comment for rpcrdma_buffer_destroy
  xprtrdma: Replace outdated comment for rpcrdma_ep_post
  xprtrdma: Update comments in frwr_op_send
  SUNRPC: Fix some kernel doc complaints
  SUNRPC: Simplify defining common RPC trace events
  NFS: Fix NFSv4 symbolic trace point output
  xprtrdma: Trace mapping, alloc, and dereg failures
  xprtrdma: Add trace points for calls to transport switch methods
  xprtrdma: Relocate the xprtrdma_mr_map trace points
  xprtrdma: Clean up of xprtrdma chunk trace points
  xprtrdma: Remove unused fields from rpcrdma_ia
  xprtrdma: Cull dprintk() call sites
  ...
 2019-01-02 16:35:23 -08:00
Daniel Borkmann 979d63d50c bpf: prevent out of bounds speculation on pointer arithmetic 
Jann reported that the original commit back in b2157399cc
("bpf: prevent out-of-bounds speculation") was not sufficient
to stop CPU from speculating out of bounds memory access:
While b2157399cc only focussed on masking array map access
for unprivileged users for tail calls and data access such
that the user provided index gets sanitized from BPF program
and syscall side, there is still a more generic form affected
from BPF programs that applies to most maps that hold user
data in relation to dynamic map access when dealing with
unknown scalars or "slow" known scalars as access offset, for
example:

  - Load a map value pointer into R6
  - Load an index into R7
  - Do a slow computation (e.g. with a memory dependency) that
    loads a limit into R8 (e.g. load the limit from a map for
    high latency, then mask it to make the verifier happy)
  - Exit if R7 >= R8 (mispredicted branch)
  - Load R0 = R6[R7]
  - Load R0 = R6[R0]

For unknown scalars there are two options in the BPF verifier
where we could derive knowledge from in order to guarantee
safe access to the memory: i) While </>/<=/>= variants won't
allow to derive any lower or upper bounds from the unknown
scalar where it would be safe to add it to the map value
pointer, it is possible through ==/!= test however. ii) another
option is to transform the unknown scalar into a known scalar,
for example, through ALU ops combination such as R &= <imm>
followed by R |= <imm> or any similar combination where the
original information from the unknown scalar would be destroyed
entirely leaving R with a constant. The initial slow load still
precedes the latter ALU ops on that register, so the CPU
executes speculatively from that point. Once we have the known
scalar, any compare operation would work then. A third option
only involving registers with known scalars could be crafted
as described in [0] where a CPU port (e.g. Slow Int unit)
would be filled with many dependent computations such that
the subsequent condition depending on its outcome has to wait
for evaluation on its execution port and thereby executing
speculatively if the speculated code can be scheduled on a
different execution port, or any other form of mistraining
as described in [1], for example. Given this is not limited
to only unknown scalars, not only map but also stack access
is affected since both is accessible for unprivileged users
and could potentially be used for out of bounds access under
speculation.

In order to prevent any of these cases, the verifier is now
sanitizing pointer arithmetic on the offset such that any
out of bounds speculation would be masked in a way where the
pointer arithmetic result in the destination register will
stay unchanged, meaning offset masked into zero similar as
in array_index_nospec() case. With regards to implementation,
there are three options that were considered: i) new insn
for sanitation, ii) push/pop insn and sanitation as inlined
BPF, iii) reuse of ax register and sanitation as inlined BPF.

Option i) has the downside that we end up using from reserved
bits in the opcode space, but also that we would require
each JIT to emit masking as native arch opcodes meaning
mitigation would have slow adoption till everyone implements
it eventually which is counter-productive. Option ii) and iii)
have both in common that a temporary register is needed in
order to implement the sanitation as inlined BPF since we
are not allowed to modify the source register. While a push /
pop insn in ii) would be useful to have in any case, it
requires once again that every JIT needs to implement it
first. While possible, amount of changes needed would also
be unsuitable for a -stable patch. Therefore, the path which
has fewer changes, less BPF instructions for the mitigation
and does not require anything to be changed in the JITs is
option iii) which this work is pursuing. The ax register is
already mapped to a register in all JITs (modulo arm32 where
it's mapped to stack as various other BPF registers there)
and used in constant blinding for JITs-only so far. It can
be reused for verifier rewrites under certain constraints.
The interpreter's tmp "register" has therefore been remapped
into extending the register set with hidden ax register and
reusing that for a number of instructions that needed the
prior temporary variable internally (e.g. div, mod). This
allows for zero increase in stack space usage in the interpreter,
and enables (restricted) generic use in rewrites otherwise as
long as such a patchlet does not make use of these instructions.
The sanitation mask is dynamic and relative to the offset the
map value or stack pointer currently holds.

There are various cases that need to be taken under consideration
for the masking, e.g. such operation could look as follows:
ptr += val or val += ptr or ptr -= val. Thus, the value to be
sanitized could reside either in source or in destination
register, and the limit is different depending on whether
the ALU op is addition or subtraction and depending on the
current known and bounded offset. The limit is derived as
follows: limit := max_value_size - (smin_value + off). For
subtraction: limit := umax_value + off. This holds because
we do not allow any pointer arithmetic that would
temporarily go out of bounds or would have an unknown
value with mixed signed bounds where it is unclear at
verification time whether the actual runtime value would
be either negative or positive. For example, we have a
derived map pointer value with constant offset and bounded
one, so limit based on smin_value works because the verifier
requires that statically analyzed arithmetic on the pointer
must be in bounds, and thus it checks if resulting
smin_value + off and umax_value + off is still within map
value bounds at time of arithmetic in addition to time of
access. Similarly, for the case of stack access we derive
the limit as follows: MAX_BPF_STACK + off for subtraction
and -off for the case of addition where off := ptr_reg->off +
ptr_reg->var_off.value. Subtraction is a special case for
the masking which can be in form of ptr += -val, ptr -= -val,
or ptr -= val. In the first two cases where we know that
the value is negative, we need to temporarily negate the
value in order to do the sanitation on a positive value
where we later swap the ALU op, and restore original source
register if the value was in source.

The sanitation of pointer arithmetic alone is still not fully
sufficient as is, since a scenario like the following could
happen ...

  PTR += 0x1000 (e.g. K-based imm)
  PTR -= BIG_NUMBER_WITH_SLOW_COMPARISON
  PTR += 0x1000
  PTR -= BIG_NUMBER_WITH_SLOW_COMPARISON
  [...]

... which under speculation could end up as ...

  PTR += 0x1000
  PTR -= 0 [ truncated by mitigation ]
  PTR += 0x1000
  PTR -= 0 [ truncated by mitigation ]
  [...]

... and therefore still access out of bounds. To prevent such
case, the verifier is also analyzing safety for potential out
of bounds access under speculative execution. Meaning, it is
also simulating pointer access under truncation. We therefore
"branch off" and push the current verification state after the
ALU operation with known 0 to the verification stack for later
analysis. Given the current path analysis succeeded it is
likely that the one under speculation can be pruned. In any
case, it is also subject to existing complexity limits and
therefore anything beyond this point will be rejected. In
terms of pruning, it needs to be ensured that the verification
state from speculative execution simulation must never prune
a non-speculative execution path, therefore, we mark verifier
state accordingly at the time of push_stack(). If verifier
detects out of bounds access under speculative execution from
one of the possible paths that includes a truncation, it will
reject such program.

Given we mask every reg-based pointer arithmetic for
unprivileged programs, we've been looking into how it could
affect real-world programs in terms of size increase. As the
majority of programs are targeted for privileged-only use
case, we've unconditionally enabled masking (with its alu
restrictions on top of it) for privileged programs for the
sake of testing in order to check i) whether they get rejected
in its current form, and ii) by how much the number of
instructions and size will increase. We've tested this by
using Katran, Cilium and test_l4lb from the kernel selftests.
For Katran we've evaluated balancer_kern.o, Cilium bpf_lxc.o
and an older test object bpf_lxc_opt_-DUNKNOWN.o and l4lb
we've used test_l4lb.o as well as test_l4lb_noinline.o. We
found that none of the programs got rejected by the verifier
with this change, and that impact is rather minimal to none.
balancer_kern.o had 13,904 bytes (1,738 insns) xlated and
7,797 bytes JITed before and after the change. Most complex
program in bpf_lxc.o had 30,544 bytes (3,817 insns) xlated
and 18,538 bytes JITed before and after and none of the other
tail call programs in bpf_lxc.o had any changes either. For
the older bpf_lxc_opt_-DUNKNOWN.o object we found a small
increase from 20,616 bytes (2,576 insns) and 12,536 bytes JITed
before to 20,664 bytes (2,582 insns) and 12,558 bytes JITed
after the change. Other programs from that object file had
similar small increase. Both test_l4lb.o had no change and
remained at 6,544 bytes (817 insns) xlated and 3,401 bytes
JITed and for test_l4lb_noinline.o constant at 5,080 bytes
(634 insns) xlated and 3,313 bytes JITed. This can be explained
in that LLVM typically optimizes stack based pointer arithmetic
by using K-based operations and that use of dynamic map access
is not overly frequent. However, in future we may decide to
optimize the algorithm further under known guarantees from
branch and value speculation. Latter seems also unclear in
terms of prediction heuristics that today's CPUs apply as well
as whether there could be collisions in e.g. the predictor's
Value History/Pattern Table for triggering out of bounds access,
thus masking is performed unconditionally at this point but could
be subject to relaxation later on. We were generally also
brainstorming various other approaches for mitigation, but the
blocker was always lack of available registers at runtime and/or
overhead for runtime tracking of limits belonging to a specific
pointer. Thus, we found this to be minimally intrusive under
given constraints.

With that in place, a simple example with sanitized access on
unprivileged load at post-verification time looks as follows:

  # bpftool prog dump xlated id 282
  [...]
  28: (79) r1 = *(u64 *)(r7 +0)
  29: (79) r2 = *(u64 *)(r7 +8)
  30: (57) r1 &= 15
  31: (79) r3 = *(u64 *)(r0 +4608)
  32: (57) r3 &= 1
  33: (47) r3 |= 1
  34: (2d) if r2 > r3 goto pc+19
  35: (b4) (u32) r11 = (u32) 20479  |
  36: (1f) r11 -= r2                | Dynamic sanitation for pointer
  37: (4f) r11 |= r2                | arithmetic with registers
  38: (87) r11 = -r11               | containing bounded or known
  39: (c7) r11 s>>= 63              | scalars in order to prevent
  40: (5f) r11 &= r2                | out of bounds speculation.
  41: (0f) r4 += r11                |
  42: (71) r4 = *(u8 *)(r4 +0)
  43: (6f) r4 <<= r1
  [...]

For the case where the scalar sits in the destination register
as opposed to the source register, the following code is emitted
for the above example:

  [...]
  16: (b4) (u32) r11 = (u32) 20479
  17: (1f) r11 -= r2
  18: (4f) r11 |= r2
  19: (87) r11 = -r11
  20: (c7) r11 s>>= 63
  21: (5f) r2 &= r11
  22: (0f) r2 += r0
  23: (61) r0 = *(u32 *)(r2 +0)
  [...]

JIT blinding example with non-conflicting use of r10:

  [...]
   d5:	je     0x0000000000000106    _
   d7:	mov    0x0(%rax),%edi       |
   da:	mov    $0xf153246,%r10d     | Index load from map value and
   e0:	xor    $0xf153259,%r10      | (const blinded) mask with 0x1f.
   e7:	and    %r10,%rdi            |_
   ea:	mov    $0x2f,%r10d          |
   f0:	sub    %rdi,%r10            | Sanitized addition. Both use r10
   f3:	or     %rdi,%r10            | but do not interfere with each
   f6:	neg    %r10                 | other. (Neither do these instructions
   f9:	sar    $0x3f,%r10           | interfere with the use of ax as temp
   fd:	and    %r10,%rdi            | in interpreter.)
  100:	add    %rax,%rdi            |_
  103:	mov    0x0(%rdi),%eax
 [...]

Tested that it fixes Jann's reproducer, and also checked that test_verifier
and test_progs suite with interpreter, JIT and JIT with hardening enabled
on x86-64 and arm64 runs successfully.

  [0] Speculose: Analyzing the Security Implications of Speculative
      Execution in CPUs, Giorgi Maisuradze and Christian Rossow,
      https://arxiv.org/pdf/1801.04084.pdf

  [1] A Systematic Evaluation of Transient Execution Attacks and
      Defenses, Claudio Canella, Jo Van Bulck, Michael Schwarz,
      Moritz Lipp, Benjamin von Berg, Philipp Ortner, Frank Piessens,
      Dmitry Evtyushkin, Daniel Gruss,
      https://arxiv.org/pdf/1811.05441.pdf

Fixes: b2157399cc ("bpf: prevent out-of-bounds speculation")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
 2019-01-02 16:01:24 -08:00
Daniel Borkmann b7137c4eab bpf: fix check_map_access smin_value test when pointer contains offset 
In check_map_access() we probe actual bounds through __check_map_access()
with offset of reg->smin_value + off for lower bound and offset of
reg->umax_value + off for the upper bound. However, even though the
reg->smin_value could have a negative value, the final result of the
sum with off could be positive when pointer arithmetic with known and
unknown scalars is combined. In this case we reject the program with
an error such as "R<x> min value is negative, either use unsigned index
or do a if (index >=0) check." even though the access itself would be
fine. Therefore extend the check to probe whether the actual resulting
reg->smin_value + off is less than zero.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
 2019-01-02 16:01:24 -08:00
Daniel Borkmann 9d7eceede7 bpf: restrict unknown scalars of mixed signed bounds for unprivileged 
For unknown scalars of mixed signed bounds, meaning their smin_value is
negative and their smax_value is positive, we need to reject arithmetic
with pointer to map value. For unprivileged the goal is to mask every
map pointer arithmetic and this cannot reliably be done when it is
unknown at verification time whether the scalar value is negative or
positive. Given this is a corner case, the likelihood of breaking should
be very small.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
 2019-01-02 16:01:24 -08:00
Daniel Borkmann e4298d2583 bpf: restrict stack pointer arithmetic for unprivileged 
Restrict stack pointer arithmetic for unprivileged users in that
arithmetic itself must not go out of bounds as opposed to the actual
access later on. Therefore after each adjust_ptr_min_max_vals() with
a stack pointer as a destination we simulate a check_stack_access()
of 1 byte on the destination and once that fails the program is
rejected for unprivileged program loads. This is analog to map
value pointer arithmetic and needed for masking later on.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
 2019-01-02 16:01:24 -08:00
Daniel Borkmann 0d6303db79 bpf: restrict map value pointer arithmetic for unprivileged 
Restrict map value pointer arithmetic for unprivileged users in that
arithmetic itself must not go out of bounds as opposed to the actual
access later on. Therefore after each adjust_ptr_min_max_vals() with a
map value pointer as a destination it will simulate a check_map_access()
of 1 byte on the destination and once that fails the program is rejected
for unprivileged program loads. We use this later on for masking any
pointer arithmetic with the remainder of the map value space. The
likelihood of breaking any existing real-world unprivileged eBPF
program is very small for this corner case.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
 2019-01-02 16:01:24 -08:00
Daniel Borkmann 9b73bfdd08 bpf: enable access to ax register also from verifier rewrite 
Right now we are using BPF ax register in JIT for constant blinding as
well as in interpreter as temporary variable. Verifier will not be able
to use it simply because its use will get overridden from the former in
bpf_jit_blind_insn(). However, it can be made to work in that blinding
will be skipped if there is prior use in either source or destination
register on the instruction. Taking constraints of ax into account, the
verifier is then open to use it in rewrites under some constraints. Note,
ax register already has mappings in every eBPF JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
 2019-01-02 16:01:24 -08:00
Daniel Borkmann 144cd91c4c bpf: move tmp variable into ax register in interpreter 
This change moves the on-stack 64 bit tmp variable in ___bpf_prog_run()
into the hidden ax register. The latter is currently only used in JITs
for constant blinding as a temporary scratch register, meaning the BPF
interpreter will never see the use of ax. Therefore it is safe to use
it for the cases where tmp has been used earlier. This is needed to later
on allow restricted hidden use of ax in both interpreter and JITs.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
 2019-01-02 16:01:24 -08:00
Daniel Borkmann c08435ec7f bpf: move {prev_,}insn_idx into verifier env 
Move prev_insn_idx and insn_idx from the do_check() function into
the verifier environment, so they can be read inside the various
helper functions for handling the instructions. It's easier to put
this into the environment rather than changing all call-sites only
to pass it along. insn_idx is useful in particular since this later
on allows to hold state in env->insn_aux_data[env->insn_idx].

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
 2019-01-02 16:01:24 -08:00
Linus Torvalds d9a7fa67b4 Merge branch 'next-seccomp' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 
Pull seccomp updates from James Morris:

 - Add SECCOMP_RET_USER_NOTIF

 - seccomp fixes for sparse warnings and s390 build (Tycho)

* 'next-seccomp' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  seccomp, s390: fix build for syscall type change
  seccomp: fix poor type promotion
  samples: add an example of seccomp user trap
  seccomp: add a return code to trap to userspace
  seccomp: switch system call argument type to void *
  seccomp: hoist struct seccomp_data recalculation higher
 2019-01-02 09:48:13 -08:00
Linus Torvalds fcf010449e kgdb patches for 4.20-rc1 
Mostly clean ups although whilst Doug's was chasing down a odd
 lockdep warning he also did some work to improved debugger resilience
 when some CPUs fail to respond to the round up request.
 
 The main changes are:
 
  * Fixing a lockdep warning on architectures that cannot use an NMI for
    the round up plus related changes to make CPU round up and all CPU
    backtrace more resilient.
 
  * Constify the arch ops tables
 
  * A couple of other small clean ups
 
 Two of the three patchsets here include changes that spill over into
 arch/.  Changes in the arch space are relatively narrow in scope
 (and directly related to kgdb). Didn't get comprehensive acks but
 all impacted maintainers were Cc:ed in good time.
 
 Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJPBAABCAA5FiEELzVBU1D3lWq6cKzwfOMlXTn3iKEFAlwonoUbHGRhbmllbC50
 aG9tcHNvbkBsaW5hcm8ub3JnAAoJEHzjJV0594ihmooP/1uzSMGQIoQMB8XeU/jT
 Da2iILybi6hGp7ILA27d0yN3tsJBxWGWs8wzNdzMo3NQ3J0o4foAUnS/R0Vjkg9w
 uphe5EA4HDsIrH05OouNb984BeEgNaC9HSqtyr9fXuh024NboULFKIm7REYm+QHT
 C5SrBtmonL1xE7FmAhudLWjl7ZlvxM6DJeoVViH4kKq0raTiILt6VJaGl9JfcAdL
 m9GEf9r/nh0sCq3GNgyc0y4BvHed+Kxzy1fsIi3jE6t8elaYYR72gNRQ5LaFxcnQ
 F04/UtH75qB4rqYsqqV1q0rFi+tj+p9wYTmxixaGWsVDX4Gb5KXuLWJhaRb5IvwC
 bdq/0IAXRr4vUL3y0tFWfCj7pHGaVc/gfXi8aieRXLGAZG+tdfuu99NCiulIZTfc
 QqZz12Z+99/qi6dK7dBQtaN8SyPeB1QXKWefeGo2Bt5QqiBmcKHxsQYMUo3nkf3J
 UXHpj4LG6Ldsi/w8VZfvXmM0/vbO/jrus9m+X2v+4tJyisjrsyv0FRnREI4avfbC
 l09P1ajv7RrAaxtab0smV9krqWZ/mSn0zcgcaD6RdKe0+SwsiP/CEx1z1Wb1MH9c
 wjEiClXjdVB39YVT0YVfG2Ho7qH8WRErxVyNb/f4QKHMXL1Mu91hFWhBBpUOGUj2
 7Jrq2zK1uWramtt7GBDpHYYH
 =Aqlc
 -----END PGP SIGNATURE-----

Merge tag 'kgdb-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux

Pull kgdb updates from Daniel Thompson:
 "Mostly clean ups although while Doug's was chasing down a odd lockdep
  warning he also did some work to improved debugger resilience when
  some CPUs fail to respond to the round up request.

  The main changes are:

   - Fixing a lockdep warning on architectures that cannot use an NMI
     for the round up plus related changes to make CPU round up and all
     CPU backtrace more resilient.

   - Constify the arch ops tables

   - A couple of other small clean ups

  Two of the three patchsets here include changes that spill over into
  arch/. Changes in the arch space are relatively narrow in scope (and
  directly related to kgdb). Didn't get comprehensive acks but all
  impacted maintainers were Cc:ed in good time"

* tag 'kgdb-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
  kgdb/treewide: constify struct kgdb_arch arch_kgdb_ops
  mips/kgdb: prepare arch_kgdb_ops for constness
  kdb: use bool for binary state indicators
  kdb: Don't back trace on a cpu that didn't round up
  kgdb: Don't round up a CPU that failed rounding up before
  kgdb: Fix kgdb_roundup_cpus() for arches who used smp_call_function()
  kgdb: Remove irq flags from roundup
 2019-01-01 15:38:14 -08:00
Linus Torvalds 495d714ad1 Tracing changes for v4.21: 
- Rework of the kprobe/uprobe and synthetic events to consolidate all
    the dynamic event code. This will make changes in the future easier.
 
  - Partial rewrite of the function graph tracing infrastructure.
    This will allow for multiple users of hooking onto functions
    to get the callback (return) of the function. This is the ground
    work for having kprobes and function graph tracer using one code base.
 
  - Clean up of the histogram code that will facilitate adding more
    features to the histograms in the future.
 
  - Addition of str_has_prefix() and a few use cases. There currently
    is a similar function strstart() that is used in a few places, but
    only returns a bool and not a length. These instances will be
    removed in the future to use str_has_prefix() instead.
 
  - A few other various clean ups as well.
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXCawlBQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qhbcAQCFeT0fWWTUxofBQz5jqsHaRnVg21+9
 X4sTldYRYEn4YgEAmWOyiwq7zvrsAu4ZwkNBMeqxn3tVymYHiGOGe3Y4BAw=
 =u96o
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Rework of the kprobe/uprobe and synthetic events to consolidate all
   the dynamic event code. This will make changes in the future easier.

 - Partial rewrite of the function graph tracing infrastructure. This
   will allow for multiple users of hooking onto functions to get the
   callback (return) of the function. This is the ground work for having
   kprobes and function graph tracer using one code base.

 - Clean up of the histogram code that will facilitate adding more
   features to the histograms in the future.

 - Addition of str_has_prefix() and a few use cases. There currently is
   a similar function strstart() that is used in a few places, but only
   returns a bool and not a length. These instances will be removed in
   the future to use str_has_prefix() instead.

 - A few other various clean ups as well.

* tag 'trace-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (57 commits)
  tracing: Use the return of str_has_prefix() to remove open coded numbers
  tracing: Have the historgram use the result of str_has_prefix() for len of prefix
  tracing: Use str_has_prefix() instead of using fixed sizes
  tracing: Use str_has_prefix() helper for histogram code
  string.h: Add str_has_prefix() helper function
  tracing: Make function ‘ftrace_exports’ static
  tracing: Simplify printf'ing in seq_print_sym
  tracing: Avoid -Wformat-nonliteral warning
  tracing: Merge seq_print_sym_short() and seq_print_sym_offset()
  tracing: Add hist trigger comments for variable-related fields
  tracing: Remove hist trigger synth_var_refs
  tracing: Use hist trigger's var_ref array to destroy var_refs
  tracing: Remove open-coding of hist trigger var_ref management
  tracing: Use var_refs[] for hist trigger reference checking
  tracing: Change strlen to sizeof for hist trigger static strings
  tracing: Remove unnecessary hist trigger struct field
  tracing: Fix ftrace_graph_get_ret_stack() to use task and not current
  seq_buf: Use size_t for len in seq_buf_puts()
  seq_buf: Make seq_buf_puts() null-terminate the buffer
  arm64: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack
  ...
 2018-12-31 11:46:59 -08:00
Linus Torvalds e3ed513bcf Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 
Pull scheduler fix from Ingo Molnar:
 "This is a revert for a lockup in cgroups-intense workloads - the real
  fixes will come later"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix infinite loop in update_blocked_averages() by reverting a9e7f6544b
 2018-12-31 09:54:17 -08:00
Linus Torvalds c40f7d74c7 sched/fair: Fix infinite loop in update_blocked_averages() by reverting a9e7f6544b 
Zhipeng Xie, Xie XiuQi and Sargun Dhillon reported lockups in the
scheduler under high loads, starting at around the v4.18 time frame,
and Zhipeng Xie tracked it down to bugs in the rq->leaf_cfs_rq_list
manipulation.

Do a (manual) revert of:

  a9e7f6544b ("sched/fair: Fix O(nr_cgroups) in load balance path")

It turns out that the list_del_leaf_cfs_rq() introduced by this commit
is a surprising property that was not considered in followup commits
such as:

  9c2791f936 ("sched/fair: Fix hierarchical order in rq->leaf_cfs_rq_list")

As Vincent Guittot explains:

 "I think that there is a bigger problem with commit a9e7f6544b and
  cfs_rq throttling:

  Let take the example of the following topology TG2 --> TG1 --> root:

   1) The 1st time a task is enqueued, we will add TG2 cfs_rq then TG1
      cfs_rq to leaf_cfs_rq_list and we are sure to do the whole branch in
      one path because it has never been used and can't be throttled so
      tmp_alone_branch will point to leaf_cfs_rq_list at the end.

   2) Then TG1 is throttled

   3) and we add TG3 as a new child of TG1.

   4) The 1st enqueue of a task on TG3 will add TG3 cfs_rq just before TG1
      cfs_rq and tmp_alone_branch will stay  on rq->leaf_cfs_rq_list.

  With commit a9e7f6544b, we can del a cfs_rq from rq->leaf_cfs_rq_list.
  So if the load of TG1 cfs_rq becomes NULL before step 2) above, TG1
  cfs_rq is removed from the list.
  Then at step 4), TG3 cfs_rq is added at the beginning of rq->leaf_cfs_rq_list
  but tmp_alone_branch still points to TG3 cfs_rq because its throttled
  parent can't be enqueued when the lock is released.
  tmp_alone_branch doesn't point to rq->leaf_cfs_rq_list whereas it should.

  So if TG3 cfs_rq is removed or destroyed before tmp_alone_branch
  points on another TG cfs_rq, the next TG cfs_rq that will be added,
  will be linked outside rq->leaf_cfs_rq_list - which is bad.

  In addition, we can break the ordering of the cfs_rq in
  rq->leaf_cfs_rq_list but this ordering is used to update and
  propagate the update from leaf down to root."

Instead of trying to work through all these cases and trying to reproduce
the very high loads that produced the lockup to begin with, simplify
the code temporarily by reverting a9e7f6544b - which change was clearly
not thought through completely.

This (hopefully) gives us a kernel that doesn't lock up so people
can continue to enjoy their holidays without worrying about regressions. ;-)

[ mingo: Wrote changelog, fixed weird spelling in code comment while at it. ]

Analyzed-by: Xie XiuQi <xiexiuqi@huawei.com>
Analyzed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reported-by: Zhipeng Xie <xiezhipeng1@huawei.com>
Reported-by: Sargun Dhillon <sargun@sargun.me>
Reported-by: Xie XiuQi <xiexiuqi@huawei.com>
Tested-by: Zhipeng Xie <xiezhipeng1@huawei.com>
Tested-by: Sargun Dhillon <sargun@sargun.me>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: <stable@vger.kernel.org> # v4.13+
Cc: Bin Li <huawei.libin@huawei.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: a9e7f6544b ("sched/fair: Fix O(nr_cgroups) in load balance path")
Link: http://lkml.kernel.org/r/1545879866-27809-1-git-send-email-xiexiuqi@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
 2018-12-30 13:54:31 +01:00
Nicholas Mc Guire 7faedcd4de kdb: use bool for binary state indicators 
defcmd_in_progress  is the state trace for command group processing
- within a command group or not -  usable  is an indicator if a command
set is valid (allocated/non-empty) - so use a bool for those binary
indication here.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
 2018-12-30 08:31:52 +00:00
Douglas Anderson 162bc7f5af kdb: Don't back trace on a cpu that didn't round up 
If you have a CPU that fails to round up and then run 'btc' you'll end
up crashing in kdb becaue we dereferenced NULL.  Let's add a check.
It's wise to also set the task to NULL when leaving the debugger so
that if we fail to round up on a later entry into the debugger we
won't backtrace a stale task.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
 2018-12-30 08:31:23 +00:00
Douglas Anderson 87b0959285 kgdb: Don't round up a CPU that failed rounding up before 
If we're using the default implementation of kgdb_roundup_cpus() that
uses smp_call_function_single_async() we can end up hanging
kgdb_roundup_cpus() if we try to round up a CPU that failed to round
up before.

Specifically smp_call_function_single_async() will try to wait on the
csd lock for the CPU that we're trying to round up.  If the previous
round up never finished then that lock could still be held and we'll
just sit there hanging.

There's not a lot of use trying to round up a CPU that failed to round
up before.  Let's keep a flag that indicates whether the CPU started
but didn't finish to round up before.  If we see that flag set then
we'll skip the next round up.

In general we have a few goals here:
- We never want to end up calling smp_call_function_single_async()
  when the csd is still locked.  This is accomplished because
  flush_smp_call_function_queue() unlocks the csd _before_ invoking
  the callback.  That means that when kgdb_nmicallback() runs we know
  for sure the the csd is no longer locked.  Thus when we set
  "rounding_up = false" we know for sure that the csd is unlocked.
- If there are no timeouts rounding up we should never skip a round
  up.

NOTE #1: In general trying to continue running after failing to round
up CPUs doesn't appear to be supported in the debugger.  When I
simulate this I find that kdb reports "Catastrophic error detected"
when I try to continue.  I can overrule and continue anyway, but it
should be noted that we may be entering the land of dragons here.
Possibly the "Catastrophic error detected" was added _because_ of the
future failure to round up, but even so this is an area of the code
that hasn't been strongly tested.

NOTE #2: I did a bit of testing before and after this change.  I
introduced a 10 second hang in the kernel while holding a spinlock
that I could invoke on a certain CPU with 'taskset -c 3 cat /sys/...".

Before this change if I did:
- Invoke hang
- Enter debugger
- g (which warns about Catastrophic error, g again to go anyway)
- g
- Enter debugger

...I'd hang the rest of the 10 seconds without getting a debugger
prompt.  After this change I end up in the debugger the 2nd time after
only 1 second with the standard warning about 'Timed out waiting for
secondary CPUs.'

I'll also note that once the CPU finished waiting I could actually
debug it (aka "btc" worked)

I won't promise that everything works perfectly if the errant CPU
comes back at just the wrong time (like as we're entering or exiting
the debugger) but it certainly seems like an improvement.

NOTE #3: setting 'kgdb_info[cpu].rounding_up = false' is in
kgdb_nmicallback() instead of kgdb_call_nmi_hook() because some
implementations override kgdb_call_nmi_hook().  It shouldn't hurt to
have it in kgdb_nmicallback() in any case.

NOTE #4: this logic is really only needed because there is no API call
like "smp_try_call_function_single_async()" or "smp_csd_is_locked()".
If such an API existed then we'd use it instead, but it seemed a bit
much to add an API like this just for kgdb.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
 2018-12-30 08:29:13 +00:00
Douglas Anderson 3cd99ac355 kgdb: Fix kgdb_roundup_cpus() for arches who used smp_call_function() 
When I had lockdep turned on and dropped into kgdb I got a nice splat
on my system.  Specifically it hit:
  DEBUG_LOCKS_WARN_ON(current->hardirq_context)

Specifically it looked like this:
  sysrq: SysRq : DEBUG
  ------------[ cut here ]------------
  DEBUG_LOCKS_WARN_ON(current->hardirq_context)
  WARNING: CPU: 0 PID: 0 at .../kernel/locking/lockdep.c:2875 lockdep_hardirqs_on+0xf0/0x160
  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.19.0 #27
  pstate: 604003c9 (nZCv DAIF +PAN -UAO)
  pc : lockdep_hardirqs_on+0xf0/0x160
  ...
  Call trace:
   lockdep_hardirqs_on+0xf0/0x160
   trace_hardirqs_on+0x188/0x1ac
   kgdb_roundup_cpus+0x14/0x3c
   kgdb_cpu_enter+0x53c/0x5cc
   kgdb_handle_exception+0x180/0x1d4
   kgdb_compiled_brk_fn+0x30/0x3c
   brk_handler+0x134/0x178
   do_debug_exception+0xfc/0x178
   el1_dbg+0x18/0x78
   kgdb_breakpoint+0x34/0x58
   sysrq_handle_dbg+0x54/0x5c
   __handle_sysrq+0x114/0x21c
   handle_sysrq+0x30/0x3c
   qcom_geni_serial_isr+0x2dc/0x30c
  ...
  ...
  irq event stamp: ...45
  hardirqs last  enabled at (...44): [...] __do_softirq+0xd8/0x4e4
  hardirqs last disabled at (...45): [...] el1_irq+0x74/0x130
  softirqs last  enabled at (...42): [...] _local_bh_enable+0x2c/0x34
  softirqs last disabled at (...43): [...] irq_exit+0xa8/0x100
  ---[ end trace adf21f830c46e638 ]---

Looking closely at it, it seems like a really bad idea to be calling
local_irq_enable() in kgdb_roundup_cpus().  If nothing else that seems
like it could violate spinlock semantics and cause a deadlock.

Instead, let's use a private csd alongside
smp_call_function_single_async() to round up the other CPUs.  Using
smp_call_function_single_async() doesn't require interrupts to be
enabled so we can remove the offending bit of code.

In order to avoid duplicating this across all the architectures that
use the default kgdb_roundup_cpus(), we'll add a "weak" implementation
to debug_core.c.

Looking at all the people who previously had copies of this code,
there were a few variants.  I've attempted to keep the variants
working like they used to.  Specifically:
* For arch/arc we passed NULL to kgdb_nmicallback() instead of
  get_irq_regs().
* For arch/mips there was a bit of extra code around
  kgdb_nmicallback()

NOTE: In this patch we will still get into trouble if we try to round
up a CPU that failed to round up before.  We'll try to round it up
again and potentially hang when we try to grab the csd lock.  That's
not new behavior but we'll still try to do better in a future patch.

Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
 2018-12-30 08:28:02 +00:00
Douglas Anderson 9ef7fa507d kgdb: Remove irq flags from roundup 
The function kgdb_roundup_cpus() was passed a parameter that was
documented as:

> the flags that will be used when restoring the interrupts. There is
> local_irq_save() call before kgdb_roundup_cpus().

Nobody used those flags.  Anyone who wanted to temporarily turn on
interrupts just did local_irq_enable() and local_irq_disable() without
looking at them.  So we can definitely remove the flags.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
 2018-12-30 08:24:21 +00:00
Linus Torvalds 769e47094d Kconfig updates for v4.21 
- support -y option for merge_config.sh to avoid downgrading =y to =m
 
  - remove S_OTHER symbol type, and touch include/config/*.h files correctly
 
  - fix file name and line number in lexer warnings
 
  - fix memory leak when EOF is encountered in quotation
 
  - resolve all shift/reduce conflicts of the parser
 
  - warn no new line at end of file
 
  - make 'source' statement more strict to take only string literal
 
  - rewrite the lexer and remove the keyword lookup table
 
  - convert to SPDX License Identifier
 
  - compile C files independently instead of including them from zconf.y
 
  - fix various warnings of gconfig
 
  - misc cleanups
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJcJieuAAoJED2LAQed4NsGHlIP/1s0fQ86XD9dIMyHzAO0gh2f
 7rylfe2kEXJgIzJ0DyZdLu4iZtwbkEUqTQrRS1abriNGVemPkfBAnZdM5d92lOQX
 3iREa700AJ2xo7V7gYZ6AbhZoG3p0S9U9Q2qE5S+tFTe8c2Gy4xtjnODF+Vel85r
 S0P8tF5sE1/d00lm+yfMI/CJVfDjyNaMm+aVEnL0kZTPiRkaktjWgo6Fc2p4z1L5
 HFmMMP6/iaXmRZ+tHJGPQ2AT70GFVZw5ePxPcl50EotUP25KHbuUdzs8wDpYm3U/
 rcESVsIFpgqHWmTsdBk6dZk0q8yFZNkMlkaP/aYukVZpUn/N6oAXgTFckYl8dmQL
 fQBkQi6DTfr9EBPVbj18BKm7xI3Y4DdQ2fzTfYkJ2XwNRGFA5r9N3sjd7ZTVGjxC
 aeeMHCwvGdSx1x8PeZAhZfsUHW8xVDMSQiT713+ljBY+6cwzA+2NF0kP7B6OAqwr
 ETFzd4Xu2/lZcL7gQRH8WU3L2S5iedmDG6RnZgJMXI0/9V4qAA+nlsWaCgnl1TgA
 mpxYlLUMrd6AUJevE34FlnyFdk8IMn9iKRFsvF0f3doO5C7QzTVGqFdJu5a0CuWO
 4NBJvZjFT8/4amoWLfnDlfApWXzTfwLbKG+r6V2F30fLuXpYg5LxWhBoGRPYLZSq
 oi4xN1Mpx3TvXz6WcKVZ
 =r3Fl
 -----END PGP SIGNATURE-----

Merge tag 'kconfig-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kconfig updates from Masahiro Yamada:

 - support -y option for merge_config.sh to avoid downgrading =y to =m

 - remove S_OTHER symbol type, and touch include/config/*.h files correctly

 - fix file name and line number in lexer warnings

 - fix memory leak when EOF is encountered in quotation

 - resolve all shift/reduce conflicts of the parser

 - warn no new line at end of file

 - make 'source' statement more strict to take only string literal

 - rewrite the lexer and remove the keyword lookup table

 - convert to SPDX License Identifier

 - compile C files independently instead of including them from zconf.y

 - fix various warnings of gconfig

 - misc cleanups

* tag 'kconfig-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (39 commits)
  kconfig: surround dbg_sym_flags with #ifdef DEBUG to fix gconf warning
  kconfig: split images.c out of qconf.cc/gconf.c to fix gconf warnings
  kconfig: add static qualifiers to fix gconf warnings
  kconfig: split the lexer out of zconf.y
  kconfig: split some C files out of zconf.y
  kconfig: convert to SPDX License Identifier
  kconfig: remove keyword lookup table entirely
  kconfig: update current_pos in the second lexer
  kconfig: switch to ASSIGN_VAL state in the second lexer
  kconfig: stop associating kconf_id with yylval
  kconfig: refactor end token rules
  kconfig: stop supporting '.' and '/' in unquoted words
  treewide: surround Kconfig file paths with double quotes
  microblaze: surround string default in Kconfig with double quotes
  kconfig: use T_WORD instead of T_VARIABLE for variables
  kconfig: use specific tokens instead of T_ASSIGN for assignments
  kconfig: refactor scanning and parsing "option" properties
  kconfig: use distinct tokens for type and default properties
  kconfig: remove redundant token defines
  kconfig: rename depends_list to comment_option_list
  ...
 2018-12-29 13:03:29 -08:00
Linus Torvalds 6f9d71c9c7 Merge branch 'for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 
Pull cgroup updates from Tejun Heo:

 - Waiman's cgroup2 cpuset support has been finally merged closing one
   of the last remaining feature gaps.

 - cgroup.procs could show non-leader threads when cgroup2 threaded mode
   was used in certain ways. I forgot to push the fix during the last
   cycle.

 - A patch to fix mount option parsing when all mount options have been
   consumed by someone else (LSM).

 - cgroup_no_v1 boot param can now block named cgroup1 hierarchies too.

* 'for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: Add named hierarchy disabling to cgroup_no_v1 boot param
  cgroup: fix parsing empty mount option string
  cpuset: Remove set but not used variable 'cs'
  cgroup: fix CSS_TASK_ITER_PROCS
  cgroup: Add .__DEBUG__. prefix to debug file names
  cpuset: Minor cgroup2 interface updates
  cpuset: Expose cpuset.cpus.subpartitions with cgroup_debug
  cpuset: Add documentation about the new "cpuset.sched.partition" flag
  cpuset: Use descriptive text when reading/writing cpuset.sched.partition
  cpuset: Expose cpus.effective and mems.effective on cgroup v2 root
  cpuset: Make generate_sched_domains() work with partition
  cpuset: Make CPU hotplug work with partition
  cpuset: Track cpusets that use parent's effective_cpus
  cpuset: Add an error state to cpuset.sched.partition
  cpuset: Add new v2 cpuset.sched.partition flag
  cpuset: Simply allocation and freeing of cpumasks
  cpuset: Define data structures to support scheduling partition
  cpuset: Enable cpuset controller in default hierarchy
  cgroup: remove unnecessary unlikely()
 2018-12-29 10:57:20 -08:00
Linus Torvalds b07039b79c Driver core patches for 4.21-rc1 
Here is the "big" set of driver core patches for 4.21-rc1.
 
 It's not really big, just a number of small changes for some reported
 issues, some documentation updates to hopefully make it harder for
 people to abuse the driver model, and some other minor cleanups.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXCY/dA8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ylZrgCeIi+rWj0mqlyKZk0A+gurH2BPmfwAniGfiHJp
 w60Fr5/EbCqUr1d1wQIO
 =4N7R
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core patches for 4.21-rc1.

  It's not really big, just a number of small changes for some reported
  issues, some documentation updates to hopefully make it harder for
  people to abuse the driver model, and some other minor cleanups.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  mm, memory_hotplug: update a comment in unregister_memory()
  component: convert to DEFINE_SHOW_ATTRIBUTE
  sysfs: Disable lockdep for driver bind/unbind files
  driver core: Add missing dev->bus->need_parent_lock checks
  kobject: return error code if writing /sys/.../uevent fails
  driver core: Move async_synchronize_full call
  driver core: platform: Respect return code of platform_device_register_full()
  kref/kobject: Improve documentation
  drivers/base/memory.c: Use DEVICE_ATTR_RO and friends
  driver core: Replace simple_strto{l,ul} by kstrtou{l,ul}
  kernfs: Improve kernfs_notify() poll notification latency
  kobject: Fix warnings in lib/kobject_uevent.c
  kobject: drop unnecessary cast "%llu" for u64
  driver core: fix comments for device_block_probing()
  driver core: Replace simple_strtol by kstrtoint
 2018-12-28 20:44:29 -08:00
Linus Torvalds f346b0becb Merge branch 'akpm' (patches from Andrew) 
Merge misc updates from Andrew Morton:

 - large KASAN update to use arm's "software tag-based mode"

 - a few misc things

 - sh updates

 - ocfs2 updates

 - just about all of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (167 commits)
  kernel/fork.c: mark 'stack_vm_area' with __maybe_unused
  memcg, oom: notify on oom killer invocation from the charge path
  mm, swap: fix swapoff with KSM pages
  include/linux/gfp.h: fix typo
  mm/hmm: fix memremap.h, move dev_page_fault_t callback to hmm
  hugetlbfs: Use i_mmap_rwsem to fix page fault/truncate race
  hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization
  memory_hotplug: add missing newlines to debugging output
  mm: remove __hugepage_set_anon_rmap()
  include/linux/vmstat.h: remove unused page state adjustment macro
  mm/page_alloc.c: allow error injection
  mm: migrate: drop unused argument of migrate_page_move_mapping()
  blkdev: avoid migration stalls for blkdev pages
  mm: migrate: provide buffer_migrate_page_norefs()
  mm: migrate: move migrate_page_lock_buffers()
  mm: migrate: lock buffers before migrate_page_move_mapping()
  mm: migration: factor out code to compute expected number of page references
  mm, page_alloc: enable pcpu_drain with zone capability
  kmemleak: add config to select auto scan
  mm/page_alloc.c: don't call kasan_free_pages() at deferred mem init
  ...
 2018-12-28 16:55:46 -08:00
Linus Torvalds af7ddd8a62 DMA mapping updates for Linux 4.21 
A huge update this time, but a lot of that is just consolidating or
 removing code:
 
  - provide a common DMA_MAPPING_ERROR definition and avoid indirect
    calls for dma_map_* error checking
  - use direct calls for the DMA direct mapping case, avoiding huge
    retpoline overhead for high performance workloads
  - merge the swiotlb dma_map_ops into dma-direct
  - provide a generic remapping DMA consistent allocator for architectures
    that have devices that perform DMA that is not cache coherent. Based
    on the existing arm64 implementation and also used for csky now.
  - improve the dma-debug infrastructure, including dynamic allocation
    of entries (Robin Murphy)
  - default to providing chaining scatterlist everywhere, with opt-outs
    for the few architectures (alpha, parisc, most arm32 variants) that
    can't cope with it
  - misc sparc32 dma-related cleanups
  - remove the dma_mark_clean arch hook used by swiotlb on ia64 and
    replace it with the generic noncoherent infrastructure
  - fix the return type of dma_set_max_seg_size (Niklas Söderlund)
  - move the dummy dma ops for not DMA capable devices from arm64 to
    common code (Robin Murphy)
  - ensure dma_alloc_coherent returns zeroed memory to avoid kernel data
    leaks through userspace.  We already did this for most common
    architectures, but this ensures we do it everywhere.
    dma_zalloc_coherent has been deprecated and can hopefully be
    removed after -rc1 with a coccinelle script.
 -----BEGIN PGP SIGNATURE-----
 
 iQI/BAABCgApFiEEgdbnc3r/njty3Iq9D55TZVIEUYMFAlwctQgLHGhjaEBsc3Qu
 ZGUACgkQD55TZVIEUYMxgQ//dBpAfS4/J76CdAbYry2zqgcOUU9hIrD6NHiEMWov
 ltJxyvEl3LsUmIdEj3aCrYL9jZN0qsnCzn5BVj2c3jDIVgD64fAr7HDf/PbEEfKb
 j6/GgEnVLPZV+sQMvhNA5jOzHrkseaqPa4/pNLFZ/l8jnuZ2d+btusDWJpMoVDer
 TXVwtIfgeIu0gTygYOShLYXd5qptWKWsZEpbTZOO2sE6+x+ZJX7yQYUxYDTlcOIj
 JWVO2l5QNHPc5T9o2at+6L5aNUvnZOxT79sWgyZLn0Kc+FagKAVwfLqUEl0v7foG
 8k/xca5/8p3afB1DfrIrtplJqis7cVgdyGxriwuuoO8X4F0nPyWwpGmxsBhrWwwl
 xTqC4UorEJ7QwoP6Azopk/vYI2QXIUBLjuCJCuFXZj9+2BGf4IfvBY1S2cLM9qLs
 HMcxQonuXJii044KEFS96ePEuiT+igVINweIFBKWcgNCEG0UQtyL6RQ1U5297ipF
 JiWZAqD+p9X52UdKS+oKfAiZEekMXn6Xyo97+YCiNpfOo0GP5eEcwhL+JpY4AiRq
 apPXtsRy2o1s8yfjdraUIM2Mc2n62vFKb35oUbGCd/QO9piPrFQHl6T0HHcHk4YR
 XrUXcHieFZBCYqh7ZVa4RL8Msq1wvGuTL4Dxl43mXdsMoUFRR6eSNWLoAV4IpOLZ
 WgA=
 =in72
 -----END PGP SIGNATURE-----

Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping

Pull DMA mapping updates from Christoph Hellwig:
 "A huge update this time, but a lot of that is just consolidating or
  removing code:

   - provide a common DMA_MAPPING_ERROR definition and avoid indirect
     calls for dma_map_* error checking

   - use direct calls for the DMA direct mapping case, avoiding huge
     retpoline overhead for high performance workloads

   - merge the swiotlb dma_map_ops into dma-direct

   - provide a generic remapping DMA consistent allocator for
     architectures that have devices that perform DMA that is not cache
     coherent. Based on the existing arm64 implementation and also used
     for csky now.

   - improve the dma-debug infrastructure, including dynamic allocation
     of entries (Robin Murphy)

   - default to providing chaining scatterlist everywhere, with opt-outs
     for the few architectures (alpha, parisc, most arm32 variants) that
     can't cope with it

   - misc sparc32 dma-related cleanups

   - remove the dma_mark_clean arch hook used by swiotlb on ia64 and
     replace it with the generic noncoherent infrastructure

   - fix the return type of dma_set_max_seg_size (Niklas Söderlund)

   - move the dummy dma ops for not DMA capable devices from arm64 to
     common code (Robin Murphy)

   - ensure dma_alloc_coherent returns zeroed memory to avoid kernel
     data leaks through userspace. We already did this for most common
     architectures, but this ensures we do it everywhere.
     dma_zalloc_coherent has been deprecated and can hopefully be
     removed after -rc1 with a coccinelle script"

* tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping: (73 commits)
  dma-mapping: fix inverted logic in dma_supported
  dma-mapping: deprecate dma_zalloc_coherent
  dma-mapping: zero memory returned from dma_alloc_*
  sparc/iommu: fix ->map_sg return value
  sparc/io-unit: fix ->map_sg return value
  arm64: default to the direct mapping in get_arch_dma_ops
  PCI: Remove unused attr variable in pci_dma_configure
  ia64: only select ARCH_HAS_DMA_COHERENT_TO_PFN if swiotlb is enabled
  dma-mapping: bypass indirect calls for dma-direct
  vmd: use the proper dma_* APIs instead of direct methods calls
  dma-direct: merge swiotlb_dma_ops into the dma_direct code
  dma-direct: use dma_direct_map_page to implement dma_direct_map_sg
  dma-direct: improve addressability error reporting
  swiotlb: remove dma_mark_clean
  swiotlb: remove SWIOTLB_MAP_ERROR
  ACPI / scan: Refactor _CCA enforcement
  dma-mapping: factor out dummy DMA ops
  dma-mapping: always build the direct mapping code
  dma-mapping: move dma_cache_sync out of line
  dma-mapping: move various slow path functions out of line
  ...
 2018-12-28 14:12:21 -08:00
Linus Torvalds 0e9da3fbf7 for-4.21/block-20181221 
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAlwb7R8QHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpjiID/97oDjMhNT7rwpuMbHw855h62j1hEN/m+N3
 FI0uxivYoYZLD+eJRnMcBwHlKjrCX8iJQAcv9ffI3ThtFW7dnZT3atUacaZVR/Dt
 IrxdymdBP3qsmuaId5NYBug7rJ+AiqFJKjEvCcSPu5X397J4I3SEbzhfvYLJ/aZX
 16o0HJlVVIrcbmq1IP4HwiIIOaKXvPaw04L4z4fpeynRSWG7EAi8NLSnhlR4Rxbb
 BTiMkCTsjRCFdyO6da4fvNQKWmPGPa3bJkYy3qR99cvJCeIbQjRyCloQlWNJRRgi
 3eJpCHVxqFmN0/+DNTJVQEEr4H8o0AVucrLVct1Jc4pessenkpoUniP8vELqwlng
 Z2VHLkhTfCEmvFlk82grrYdNvGATRsrbswt/PlP4T7rBfr1IpDk8kXDWF59EL2dy
 ly35Sk3wJGHBl8qa+vEPXOAnaWdqJXuVGpwB4ifOIatOls8mOxwfZjiRc7x05/fC
 1O4rR2IfLwRqwoYHs0AJ+h6ohOSn1mkGezl2Tch1VSFcJUOHmuYvraTaUi6hblpA
 SslaAoEhO39hRBL0HsvsMeqVWM9uzqvFkLDCfNPdiA81H1258CIbo4vF8z6czCIS
 eeXnTJxVhPVbZgb3a1a93SPwM6KIDZFoIijyd+NqjpU94thlnhYD0QEcKJIKH7os
 2p4aHs6ktw==
 =TRdW
 -----END PGP SIGNATURE-----

Merge tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "This is the main pull request for block/storage for 4.21.

  Larger than usual, it was a busy round with lots of goodies queued up.
  Most notable is the removal of the old IO stack, which has been a long
  time coming. No new features for a while, everything coming in this
  week has all been fixes for things that were previously merged.

  This contains:

   - Use atomic counters instead of semaphores for mtip32xx (Arnd)

   - Cleanup of the mtip32xx request setup (Christoph)

   - Fix for circular locking dependency in loop (Jan, Tetsuo)

   - bcache (Coly, Guoju, Shenghui)
      * Optimizations for writeback caching
      * Various fixes and improvements

   - nvme (Chaitanya, Christoph, Sagi, Jay, me, Keith)
      * host and target support for NVMe over TCP
      * Error log page support
      * Support for separate read/write/poll queues
      * Much improved polling
      * discard OOM fallback
      * Tracepoint improvements

   - lightnvm (Hans, Hua, Igor, Matias, Javier)
      * Igor added packed metadata to pblk. Now drives without metadata
        per LBA can be used as well.
      * Fix from Geert on uninitialized value on chunk metadata reads.
      * Fixes from Hans and Javier to pblk recovery and write path.
      * Fix from Hua Su to fix a race condition in the pblk recovery
        code.
      * Scan optimization added to pblk recovery from Zhoujie.
      * Small geometry cleanup from me.

   - Conversion of the last few drivers that used the legacy path to
     blk-mq (me)

   - Removal of legacy IO path in SCSI (me, Christoph)

   - Removal of legacy IO stack and schedulers (me)

   - Support for much better polling, now without interrupts at all.
     blk-mq adds support for multiple queue maps, which enables us to
     have a map per type. This in turn enables nvme to have separate
     completion queues for polling, which can then be interrupt-less.
     Also means we're ready for async polled IO, which is hopefully
     coming in the next release.

   - Killing of (now) unused block exports (Christoph)

   - Unification of the blk-rq-qos and blk-wbt wait handling (Josef)

   - Support for zoned testing with null_blk (Masato)

   - sx8 conversion to per-host tag sets (Christoph)

   - IO priority improvements (Damien)

   - mq-deadline zoned fix (Damien)

   - Ref count blkcg series (Dennis)

   - Lots of blk-mq improvements and speedups (me)

   - sbitmap scalability improvements (me)

   - Make core inflight IO accounting per-cpu (Mikulas)

   - Export timeout setting in sysfs (Weiping)

   - Cleanup the direct issue path (Jianchao)

   - Export blk-wbt internals in block debugfs for easier debugging
     (Ming)

   - Lots of other fixes and improvements"

* tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block: (364 commits)
  kyber: use sbitmap add_wait_queue/list_del wait helpers
  sbitmap: add helpers for add/del wait queue handling
  block: save irq state in blkg_lookup_create()
  dm: don't reuse bio for flushes
  nvme-pci: trace SQ status on completions
  nvme-rdma: implement polling queue map
  nvme-fabrics: allow user to pass in nr_poll_queues
  nvme-fabrics: allow nvmf_connect_io_queue to poll
  nvme-core: optionally poll sync commands
  block: make request_to_qc_t public
  nvme-tcp: fix spelling mistake "attepmpt" -> "attempt"
  nvme-tcp: fix endianess annotations
  nvmet-tcp: fix endianess annotations
  nvme-pci: refactor nvme_poll_irqdisable to make sparse happy
  nvme-pci: only set nr_maps to 2 if poll queues are supported
  nvmet: use a macro for default error location
  nvmet: fix comparison of a u16 with -1
  blk-mq: enable IO poll if .nr_queues of type poll > 0
  blk-mq: change blk_mq_queue_busy() to blk_mq_queue_inflight()
  blk-mq: skip zero-queue maps in blk_mq_map_swqueue
  ...
 2018-12-28 13:19:59 -08:00
Linus Torvalds b12a9124ee y2038: more syscalls and cleanups 
This concludes the main part of the system call rework for 64-bit time_t,
 which has spread over most of year 2018, the last six system calls being
 
  - ppoll
  - pselect6
  - io_pgetevents
  - recvmmsg
  - futex
  - rt_sigtimedwait
 
 As before, nothing changes for 64-bit architectures, while 32-bit
 architectures gain another entry point that differs only in the layout
 of the timespec structure. Hopefully in the next release we can wire up
 all 22 of those system calls on all 32-bit architectures, which gives
 us a baseline version for glibc to start using them.
 
 This does not include the clock_adjtime, getrusage/waitid, and
 getitimer/setitimer system calls. I still plan to have new versions
 of those as well, but they are not required for correct operation of
 the C library since they can be emulated using the old 32-bit time_t
 based system calls.
 
 Aside from the system calls, there are also a few cleanups here,
 removing old kernel internal interfaces that have become unused after
 all references got removed. The arch/sh cleanups are part of this,
 there were posted several times over the past year without a reaction
 from the maintainers, while the corresponding changes made it into all
 other architectures.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJcHCCRAAoJEGCrR//JCVInkqsP/3TuLgSyQwolFRXcoBOjR1Ar
 JoX33GuDlAxHSqPadButVfflmRIWvL3aNMFFwcQM4uYgQ593FoHbmnusCdFgHcQ7
 Q13pGo7szbfEFxydhnDMVust/hxd5C9Y5zNSJ+eMLGLLJXosEyjd9YjRoHDROWal
 oDLqpPCArlLN1B1XFhjH8J847+JgS+hUrAfk3AOU0B2TuuFkBnRImlCGCR5JcgPh
 XIpHRBOgEMP4kZ3LjztPfS3v/XJeGrguRcbD3FsPKdPeYO9QRUiw0vahEQRr7qXL
 9hOgDq1YHPUQeUFhy3hJPCZdsDFzWoIE7ziNkZCZvGBw+qSw9i8KChGUt6PcSNlJ
 nqKJY5Wneb4svu+kOdK7d8ONbTdlVYvWf5bj/sKoNUA4BVeIjNcDXplvr3cXiDzI
 e40CcSQ3oLEvrIxMcoyNPPG63b+FYG8nMaCOx4dB4pZN7sSvZUO9a1DbDBtzxMON
 xy5Kfk1n5gIHcfBJAya5CnMQ1Jm4FCCu/LHVanYvb/nXA/2jEegSm24Md17icE/Q
 VA5jJqIdICExor4VHMsG0lLQxBJsv/QqYfT2OCO6Oykh28mjFqf+X+9Ctz1w6KVG
 VUkY1u97x8jB0M4qolGO7ZGn6P1h0TpNVFD1zDNcDt2xI63cmuhgKWiV2pv5b7No
 ty6insmmbJWt3tOOPyfb
 =yIAT
 -----END PGP SIGNATURE-----

Merge tag 'y2038-for-4.21' of ssh://gitolite.kernel.org:/pub/scm/linux/kernel/git/arnd/playground

Pull y2038 updates from Arnd Bergmann:
 "More syscalls and cleanups

  This concludes the main part of the system call rework for 64-bit
  time_t, which has spread over most of year 2018, the last six system
  calls being

    - ppoll
    - pselect6
    - io_pgetevents
    - recvmmsg
    - futex
    - rt_sigtimedwait

  As before, nothing changes for 64-bit architectures, while 32-bit
  architectures gain another entry point that differs only in the layout
  of the timespec structure. Hopefully in the next release we can wire
  up all 22 of those system calls on all 32-bit architectures, which
  gives us a baseline version for glibc to start using them.

  This does not include the clock_adjtime, getrusage/waitid, and
  getitimer/setitimer system calls. I still plan to have new versions of
  those as well, but they are not required for correct operation of the
  C library since they can be emulated using the old 32-bit time_t based
  system calls.

  Aside from the system calls, there are also a few cleanups here,
  removing old kernel internal interfaces that have become unused after
  all references got removed. The arch/sh cleanups are part of this,
  there were posted several times over the past year without a reaction
  from the maintainers, while the corresponding changes made it into all
  other architectures"

* tag 'y2038-for-4.21' of ssh://gitolite.kernel.org:/pub/scm/linux/kernel/git/arnd/playground:
  timekeeping: remove obsolete time accessors
  vfs: replace current_kernel_time64 with ktime equivalent
  timekeeping: remove timespec_add/timespec_del
  timekeeping: remove unused {read,update}_persistent_clock
  sh: remove board_time_init() callback
  sh: remove unused rtc_sh_get/set_time infrastructure
  sh: sh03: rtc: push down rtc class ops into driver
  sh: dreamcast: rtc: push down rtc class ops into driver
  y2038: signal: Add compat_sys_rt_sigtimedwait_time64
  y2038: signal: Add sys_rt_sigtimedwait_time32
  y2038: socket: Add compat_sys_recvmmsg_time64
  y2038: futex: Add support for __kernel_timespec
  y2038: futex: Move compat implementation into futex.c
  io_pgetevents: use __kernel_timespec
  pselect6: use __kernel_timespec
  ppoll: use __kernel_timespec
  signal: Add restore_user_sigmask()
  signal: Add set_user_sigmask()
 2018-12-28 12:45:04 -08:00
Matthew Wilcox 1a80dade01 Fix failure path in alloc_pid() 
The failure path removes the allocated PIDs from the wrong namespace.
This could lead to us inadvertently reusing PIDs in the leaf namespace
and leaking PIDs in parent namespaces.

Fixes: 95846ecf9d ("pid: replace pid bitmap implementation with IDR API")
Cc: <stable@vger.kernel.org>
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:42:30 -08:00
YueHaibing 0f4991e8fd kernel/fork.c: mark 'stack_vm_area' with __maybe_unused 
Fixes gcc '-Wunused-but-set-variable' warning when CONFIG_VMAP_STACK is
not set:

kernel/fork.c: In function 'dup_task_struct':
kernel/fork.c:843:20: warning:
 variable 'stack_vm_area' set but not used [-Wunused-but-set-variable]

Link: http://lkml.kernel.org/r/1545965190-2381-1-git-send-email-yuehaibing@huawei.com
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:52 -08:00
Dan Williams 063a7d1d36 mm/hmm: fix memremap.h, move dev_page_fault_t callback to hmm 
The kbuild robot reported the following on a development branch that used
memremap.h in a new path:

   In file included from arch/m68k/include/asm/pgtable_mm.h:148:0,
                     from arch/m68k/include/asm/pgtable.h:5,
                     from include/linux/memremap.h:7,
                     from drivers//dax/bus.c:3:
    arch/m68k/include/asm/motorola_pgtable.h: In function 'pgd_offset':
 >> arch/m68k/include/asm/motorola_pgtable.h:199:11: error: dereferencing pointer to incomplete type 'const struct mm_struct'
      return mm->pgd + pgd_index(address);
               ^~

The ->page_fault() callback is specific to HMM.  Move it to 'struct
hmm_devmem' where the unusual asm/pgtable.h dependency can be contained in
include/linux/hmm.h.  Longer term refactoring this dependency out of HMM
is recommended, but in the meantime memremap.h remains generic.

Link: http://lkml.kernel.org/r/154534090899.3120190.6652620807617715272.stgit@dwillia2-desk3.amr.corp.intel.com
Fixes: 5042db43cc ("mm/ZONE_DEVICE: new type of ZONE_DEVICE memory...")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:52 -08:00
Jérôme Glisse ac46d4f3c4 mm/mmu_notifier: use structure for invalidate_range_start/end calls v2 
To avoid having to change many call sites everytime we want to add a
parameter use a structure to group all parameters for the mmu_notifier
invalidate_range_start/end cakks.  No functional changes with this patch.

[akpm@linux-foundation.org: coding style fixes]
Link: http://lkml.kernel.org/r/20181205053628.3210-3-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Felix Kuehling <felix.kuehling@amd.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
From: Jérôme Glisse <jglisse@redhat.com>
Subject: mm/mmu_notifier: use structure for invalidate_range_start/end calls v3

fix build warning in migrate.c when CONFIG_MMU_NOTIFIER=n

Link: http://lkml.kernel.org/r/20181213171330.8489-3-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:50 -08:00
Oscar Salvador 65c7878413 kernel, resource: check for IORESOURCE_SYSRAM in release_mem_region_adjustable 
This is a preparation for the next patch.

Currently, we only call release_mem_region_adjustable() in __remove_pages
if the zone is not ZONE_DEVICE, because resources that belong to HMM/devm
are being released by themselves with devm_release_mem_region.

Since we do not want to touch any zone/page stuff during the removing of
the memory (but during the offlining), we do not want to check for the
zone here.  So we need another way to tell release_mem_region_adjustable()
to not realease the resource in case it belongs to HMM/devm.

HMM/devm acquires/releases a resource through
devm_request_mem_region/devm_release_mem_region.

These resources have the flag IORESOURCE_MEM, while resources acquired by
hot-add memory path (register_memory_resource()) contain
IORESOURCE_SYSTEM_RAM.

So, we can check for this flag in release_mem_region_adjustable, and if
the resource does not contain such flag, we know that we are dealing with
a HMM/devm resource, so we can back off.

Link: http://lkml.kernel.org/r/20181127162005.15833-3-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:49 -08:00
Oscar Salvador 2c2a5af6fe mm, memory_hotplug: add nid parameter to arch_remove_memory 
Patch series "Do not touch pages in hot-remove path", v2.

This patchset aims for two things:

 1) A better definition about offline and hot-remove stage
 2) Solving bugs where we can access non-initialized pages
    during hot-remove operations [2] [3].

This is achieved by moving all page/zone handling to the offline
stage, so we do not need to access pages when hot-removing memory.

[1] https://patchwork.kernel.org/cover/10691415/
[2] https://patchwork.kernel.org/patch/10547445/
[3] https://www.spinics.net/lists/linux-mm/msg161316.html

This patch (of 5):

This is a preparation for the following-up patches.  The idea of passing
the nid is that it will allow us to get rid of the zone parameter
afterwards.

Link: http://lkml.kernel.org/r/20181127162005.15833-2-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:49 -08:00
yuzhoujian ef8444ea01 mm, oom: reorganize the oom report in dump_header 
OOM report contains several sections.  The first one is the allocation
context that has triggered the OOM.  Then we have cpuset context followed
by the stack trace of the OOM path.  The tird one is the OOM memory
information.  Followed by the current memory state of all system tasks.
At last, we will show oom eligible tasks and the information about the
chosen oom victim.

One thing that makes parsing more awkward than necessary is that we do not
have a single and easily parsable line about the oom context.  This patch
is reorganizing the oom report to

1) who invoked oom and what was the allocation request

[  515.902945] tuned invoked oom-killer: gfp_mask=0x6200ca(GFP_HIGHUSER_MOVABLE), order=0, oom_score_adj=0

2) OOM stack trace

[  515.904273] CPU: 24 PID: 1809 Comm: tuned Not tainted 4.20.0-rc3+ #3
[  515.905518] Hardware name: Inspur SA5212M4/YZMB-00370-107, BIOS 4.1.10 11/14/2016
[  515.906821] Call Trace:
[  515.908062]  dump_stack+0x5a/0x73
[  515.909311]  dump_header+0x55/0x28c
[  515.914260]  oom_kill_process+0x2d8/0x300
[  515.916708]  out_of_memory+0x145/0x4a0
[  515.917932]  __alloc_pages_slowpath+0x7d2/0xa16
[  515.919157]  __alloc_pages_nodemask+0x277/0x290
[  515.920367]  filemap_fault+0x3d0/0x6c0
[  515.921529]  ? filemap_map_pages+0x2b8/0x420
[  515.922709]  ext4_filemap_fault+0x2c/0x40 [ext4]
[  515.923884]  __do_fault+0x20/0x80
[  515.925032]  __handle_mm_fault+0xbc0/0xe80
[  515.926195]  handle_mm_fault+0xfa/0x210
[  515.927357]  __do_page_fault+0x233/0x4c0
[  515.928506]  do_page_fault+0x32/0x140
[  515.929646]  ? page_fault+0x8/0x30
[  515.930770]  page_fault+0x1e/0x30

3) OOM memory information

[  515.958093] Mem-Info:
[  515.959647] active_anon:26501758 inactive_anon:1179809 isolated_anon:0
 active_file:4402672 inactive_file:483963 isolated_file:1344
 unevictable:0 dirty:4886753 writeback:0 unstable:0
 slab_reclaimable:148442 slab_unreclaimable:18741
 mapped:1347 shmem:1347 pagetables:58669 bounce:0
 free:88663 free_pcp:0 free_cma:0
...

4) current memory state of all system tasks

[  516.079544] [    744]     0   744     9211     1345   114688       82             0 systemd-journal
[  516.082034] [    787]     0   787    31764        0   143360       92             0 lvmetad
[  516.084465] [    792]     0   792    10930        1   110592      208         -1000 systemd-udevd
[  516.086865] [   1199]     0  1199    13866        0   131072      112         -1000 auditd
[  516.089190] [   1222]     0  1222    31990        1   110592      157             0 smartd
[  516.091477] [   1225]     0  1225     4864       85    81920       43             0 irqbalance
[  516.093712] [   1226]     0  1226    52612        0   258048      426             0 abrtd
[  516.112128] [   1280]     0  1280   109774       55   299008      400             0 NetworkManager
[  516.113998] [   1295]     0  1295    28817       37    69632       24             0 ksmtuned
[  516.144596] [  10718]     0 10718  2622484  1721372 15998976   267219             0 panic
[  516.145792] [  10719]     0 10719  2622484  1164767  9818112    53576             0 panic
[  516.146977] [  10720]     0 10720  2622484  1174361  9904128    53709             0 panic
[  516.148163] [  10721]     0 10721  2622484  1209070 10194944    54824             0 panic
[  516.149329] [  10722]     0 10722  2622484  1745799 14774272    91138             0 panic

5) oom context (contrains and the chosen victim).

oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),cpuset=/,mems_allowed=0-1,task=panic,pid=10737,uid=0

An admin can easily get the full oom context at a single line which
makes parsing much easier.

Link: http://lkml.kernel.org/r/1542799799-36184-1-git-send-email-ufo19890607@gmail.com
Signed-off-by: yuzhoujian <yuzhoujian@didichuxing.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Yang Shi <yang.s@alibaba-inc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:48 -08:00
Mel Gorman 1c30844d2d mm: reclaim small amounts of memory when an external fragmentation event occurs 
An external fragmentation event was previously described as

    When the page allocator fragments memory, it records the event using
    the mm_page_alloc_extfrag event. If the fallback_order is smaller
    than a pageblock order (order-9 on 64-bit x86) then it's considered
    an event that will cause external fragmentation issues in the future.

The kernel reduces the probability of such events by increasing the
watermark sizes by calling set_recommended_min_free_kbytes early in the
lifetime of the system.  This works reasonably well in general but if
there are enough sparsely populated pageblocks then the problem can still
occur as enough memory is free overall and kswapd stays asleep.

This patch introduces a watermark_boost_factor sysctl that allows a zone
watermark to be temporarily boosted when an external fragmentation causing
events occurs.  The boosting will stall allocations that would decrease
free memory below the boosted low watermark and kswapd is woken if the
calling context allows to reclaim an amount of memory relative to the size
of the high watermark and the watermark_boost_factor until the boost is
cleared.  When kswapd finishes, it wakes kcompactd at the pageblock order
to clean some of the pageblocks that may have been affected by the
fragmentation event.  kswapd avoids any writeback, slab shrinkage and swap
from reclaim context during this operation to avoid excessive system
disruption in the name of fragmentation avoidance.  Care is taken so that
kswapd will do normal reclaim work if the system is really low on memory.

This was evaluated using the same workloads as "mm, page_alloc: Spread
allocations across zones before introducing fragmentation".

1-socket Skylake machine
config-global-dhp__workload_thpfioscale XFS (no special madvise)
4 fio threads, 1 THP allocating thread
--------------------------------------

4.20-rc3 extfrag events < order 9:   804694
4.20-rc3+patch:                      408912 (49% reduction)
4.20-rc3+patch1-4:                    18421 (98% reduction)

                                   4.20.0-rc3             4.20.0-rc3
                                 lowzone-v5r8             boost-v5r8
Amean     fault-base-1      653.58 (   0.00%)      652.71 (   0.13%)
Amean     fault-huge-1        0.00 (   0.00%)      178.93 * -99.00%*

                              4.20.0-rc3             4.20.0-rc3
                            lowzone-v5r8             boost-v5r8
Percentage huge-1        0.00 (   0.00%)        5.12 ( 100.00%)

Note that external fragmentation causing events are massively reduced by
this path whether in comparison to the previous kernel or the vanilla
kernel.  The fault latency for huge pages appears to be increased but that
is only because THP allocations were successful with the patch applied.

1-socket Skylake machine
global-dhp__workload_thpfioscale-madvhugepage-xfs (MADV_HUGEPAGE)
-----------------------------------------------------------------

4.20-rc3 extfrag events < order 9:  291392
4.20-rc3+patch:                     191187 (34% reduction)
4.20-rc3+patch1-4:                   13464 (95% reduction)

thpfioscale Fault Latencies
                                   4.20.0-rc3             4.20.0-rc3
                                 lowzone-v5r8             boost-v5r8
Min       fault-base-1      912.00 (   0.00%)      905.00 (   0.77%)
Min       fault-huge-1      127.00 (   0.00%)      135.00 (  -6.30%)
Amean     fault-base-1     1467.55 (   0.00%)     1481.67 (  -0.96%)
Amean     fault-huge-1     1127.11 (   0.00%)     1063.88 *   5.61%*

                              4.20.0-rc3             4.20.0-rc3
                            lowzone-v5r8             boost-v5r8
Percentage huge-1       77.64 (   0.00%)       83.46 (   7.49%)

As before, massive reduction in external fragmentation events, some jitter
on latencies and an increase in THP allocation success rates.

2-socket Haswell machine
config-global-dhp__workload_thpfioscale XFS (no special madvise)
4 fio threads, 5 THP allocating threads
----------------------------------------------------------------

4.20-rc3 extfrag events < order 9:  215698
4.20-rc3+patch:                     200210 (7% reduction)
4.20-rc3+patch1-4:                   14263 (93% reduction)

                                   4.20.0-rc3             4.20.0-rc3
                                 lowzone-v5r8             boost-v5r8
Amean     fault-base-5     1346.45 (   0.00%)     1306.87 (   2.94%)
Amean     fault-huge-5     3418.60 (   0.00%)     1348.94 (  60.54%)

                              4.20.0-rc3             4.20.0-rc3
                            lowzone-v5r8             boost-v5r8
Percentage huge-5        0.78 (   0.00%)        7.91 ( 910.64%)

There is a 93% reduction in fragmentation causing events, there is a big
reduction in the huge page fault latency and allocation success rate is
higher.

2-socket Haswell machine
global-dhp__workload_thpfioscale-madvhugepage-xfs (MADV_HUGEPAGE)
-----------------------------------------------------------------

4.20-rc3 extfrag events < order 9: 166352
4.20-rc3+patch:                    147463 (11% reduction)
4.20-rc3+patch1-4:                  11095 (93% reduction)

thpfioscale Fault Latencies
                                   4.20.0-rc3             4.20.0-rc3
                                 lowzone-v5r8             boost-v5r8
Amean     fault-base-5     6217.43 (   0.00%)     7419.67 * -19.34%*
Amean     fault-huge-5     3163.33 (   0.00%)     3263.80 (  -3.18%)

                              4.20.0-rc3             4.20.0-rc3
                            lowzone-v5r8             boost-v5r8
Percentage huge-5       95.14 (   0.00%)       87.98 (  -7.53%)

There is a large reduction in fragmentation events with some jitter around
the latencies and success rates.  As before, the high THP allocation
success rate does mean the system is under a lot of pressure.  However, as
the fragmentation events are reduced, it would be expected that the
long-term allocation success rate would be higher.

Link: http://lkml.kernel.org/r/20181123114528.28802-5-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:48 -08:00
Dan Williams 69324b8f48 mm, devm_memremap_pages: add MEMORY_DEVICE_PRIVATE support 
In preparation for consolidating all ZONE_DEVICE enabling via
devm_memremap_pages(), teach it how to handle the constraints of
MEMORY_DEVICE_PRIVATE ranges.

[jglisse@redhat.com: call move_pfn_range_to_zone for MEMORY_DEVICE_PRIVATE]
Link: http://lkml.kernel.org/r/154275559036.76910.12434636179931292607.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jérôme Glisse <jglisse@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Reported-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:47 -08:00
Dan Williams a95c90f1e2 mm, devm_memremap_pages: fix shutdown handling 
The last step before devm_memremap_pages() returns success is to allocate
a release action, devm_memremap_pages_release(), to tear the entire setup
down.  However, the result from devm_add_action() is not checked.

Checking the error from devm_add_action() is not enough.  The api
currently relies on the fact that the percpu_ref it is using is killed by
the time the devm_memremap_pages_release() is run.  Rather than continue
this awkward situation, offload the responsibility of killing the
percpu_ref to devm_memremap_pages_release() directly.  This allows
devm_memremap_pages() to do the right thing relative to init failures and
shutdown.

Without this change we could fail to register the teardown of
devm_memremap_pages().  The likelihood of hitting this failure is tiny as
small memory allocations almost always succeed.  However, the impact of
the failure is large given any future reconfiguration, or disable/enable,
of an nvdimm namespace will fail forever as subsequent calls to
devm_memremap_pages() will fail to setup the pgmap_radix since there will
be stale entries for the physical address range.

An argument could be made to require that the ->kill() operation be set in
the @pgmap arg rather than passed in separately.  However, it helps code
readability, tracking the lifetime of a given instance, to be able to grep
the kill routine directly at the devm_memremap_pages() call site.

Link: http://lkml.kernel.org/r/154275558526.76910.7535251937849268605.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Fixes: e8d5134833 ("memremap: change devm_memremap_pages interface...")
Reviewed-by: "Jérôme Glisse" <jglisse@redhat.com>
Reported-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:47 -08:00
Dan Williams 06489cfbd9 mm, devm_memremap_pages: kill mapping "System RAM" support 
Given the fact that devm_memremap_pages() requires a percpu_ref that is
torn down by devm_memremap_pages_release() the current support for mapping
RAM is broken.

Support for remapping "System RAM" has been broken since the beginning and
there is no existing user of this this code path, so just kill the support
and make it an explicit error.

This cleanup also simplifies a follow-on patch to fix the error path when
setting a devm release action for devm_memremap_pages_release() fails.

Link: http://lkml.kernel.org/r/154275557997.76910.14689813630968180480.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: "Jérôme Glisse" <jglisse@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:47 -08:00
Dan Williams 808153e118 mm, devm_memremap_pages: mark devm_memremap_pages() EXPORT_SYMBOL_GPL 
devm_memremap_pages() is a facility that can create struct page entries
for any arbitrary range and give drivers the ability to subvert core
aspects of page management.

Specifically the facility is tightly integrated with the kernel's memory
hotplug functionality.  It injects an altmap argument deep into the
architecture specific vmemmap implementation to allow allocating from
specific reserved pages, and it has Linux specific assumptions about page
structure reference counting relative to get_user_pages() and
get_user_pages_fast().  It was an oversight and a mistake that this was
not marked EXPORT_SYMBOL_GPL from the outset.

Again, devm_memremap_pagex() exposes and relies upon core kernel internal
assumptions and will continue to evolve along with 'struct page', memory
hotplug, and support for new memory types / topologies.  Only an in-kernel
GPL-only driver is expected to keep up with this ongoing evolution.  This
interface, and functionality derived from this interface, is not suitable
for kernel-external drivers.

Link: http://lkml.kernel.org/r/154275557457.76910.16923571232582744134.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:47 -08:00
Arun KS ca79b0c211 mm: convert totalram_pages and totalhigh_pages variables to atomic 
totalram_pages and totalhigh_pages are made static inline function.

Main motivation was that managed_page_count_lock handling was complicating
things.  It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes
better to remove the lock and convert variables to atomic, with preventing
poteintial store-to-read tearing as a bonus.

[akpm@linux-foundation.org: coding style fixes]
Link: http://lkml.kernel.org/r/1542090790-21750-4-git-send-email-arunks@codeaurora.org
Signed-off-by: Arun KS <arunks@codeaurora.org>
Suggested-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:47 -08:00
Arun KS 3d6357de8a mm: reference totalram_pages and managed_pages once per function 
Patch series "mm: convert totalram_pages, totalhigh_pages and managed
pages to atomic", v5.

This series converts totalram_pages, totalhigh_pages and
zone->managed_pages to atomic variables.

totalram_pages, zone->managed_pages and totalhigh_pages updates are
protected by managed_page_count_lock, but readers never care about it.
Convert these variables to atomic to avoid readers potentially seeing a
store tear.

Main motivation was that managed_page_count_lock handling was complicating
things.  It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 It seemes better
to remove the lock and convert variables to atomic.  With the change,
preventing poteintial store-to-read tearing comes as a bonus.

This patch (of 4):

This is in preparation to a later patch which converts totalram_pages and
zone->managed_pages to atomic variables.  Please note that re-reading the
value might lead to a different value and as such it could lead to
unexpected behavior.  There are no known bugs as a result of the current
code but it is better to prevent from them in principle.

Link: http://lkml.kernel.org/r/1542090790-21750-2-git-send-email-arunks@codeaurora.org
Signed-off-by: Arun KS <arunks@codeaurora.org>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-12-28 12:11:47 -08:00
Tejun Heo 3fc9c12d27 cgroup: Add named hierarchy disabling to cgroup_no_v1 boot param 
It can be useful to inhibit all cgroup1 hierarchies especially during
transition and for debugging.  cgroup_no_v1 can block hierarchies with
controllers which leaves out the named hierarchies.  Expand it to
cover the named hierarchies so that "cgroup_no_v1=all,named" disables
all cgroup1 hierarchies.

Signed-off-by: Tejun Heo <tj@kernel.org>
Suggested-by: Marcin Pawlowski <mpawlowski@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
 2018-12-28 10:34:12 -08:00
Ondrej Mosnacek e250d91d65 cgroup: fix parsing empty mount option string 
This fixes the case where all mount options specified are consumed by an
LSM and all that's left is an empty string. In this case cgroupfs should
accept the string and not fail.

How to reproduce (with SELinux enabled):

    # umount /sys/fs/cgroup/unified
    # mount -o context=system_u:object_r:cgroup_t:s0 -t cgroup2 cgroup2 /sys/fs/cgroup/unified
    mount: /sys/fs/cgroup/unified: wrong fs type, bad option, bad superblock on cgroup2, missing codepage or helper program, or other error.
    # dmesg | tail -n 1
    [   31.575952] cgroup: cgroup2: unknown option ""

Fixes: 67e9c74b8a ("cgroup: replace __DEVEL__sane_behavior with cgroup2 fs type")
[NOTE: should apply on top of commit 5136f6365c ("cgroup: implement "nsdelegate" mount option"), older versions need manual rebase]
Suggested-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
 2018-12-28 10:32:57 -08:00
Tejun Heo 4d71c6f877 Merge branch 'for-4.20-fixes' into for-4.21 2018-12-27 18:05:30 -08:00
Linus Torvalds b71acb0e37 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 
Pull crypto updates from Herbert Xu:
 "API:
   - Add 1472-byte test to tcrypt for IPsec
   - Reintroduced crypto stats interface with numerous changes
   - Support incremental algorithm dumps

  Algorithms:
   - Add xchacha12/20
   - Add nhpoly1305
   - Add adiantum
   - Add streebog hash
   - Mark cts(cbc(aes)) as FIPS allowed

  Drivers:
   - Improve performance of arm64/chacha20
   - Improve performance of x86/chacha20
   - Add NEON-accelerated nhpoly1305
   - Add SSE2 accelerated nhpoly1305
   - Add AVX2 accelerated nhpoly1305
   - Add support for 192/256-bit keys in gcmaes AVX
   - Add SG support in gcmaes AVX
   - ESN for inline IPsec tx in chcr
   - Add support for CryptoCell 703 in ccree
   - Add support for CryptoCell 713 in ccree
   - Add SM4 support in ccree
   - Add SM3 support in ccree
   - Add support for chacha20 in caam/qi2
   - Add support for chacha20 + poly1305 in caam/jr
   - Add support for chacha20 + poly1305 in caam/qi2
   - Add AEAD cipher support in cavium/nitrox"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (130 commits)
  crypto: skcipher - remove remnants of internal IV generators
  crypto: cavium/nitrox - Fix build with !CONFIG_DEBUG_FS
  crypto: salsa20-generic - don't unnecessarily use atomic walk
  crypto: skcipher - add might_sleep() to skcipher_walk_virt()
  crypto: x86/chacha - avoid sleeping under kernel_fpu_begin()
  crypto: cavium/nitrox - Added AEAD cipher support
  crypto: mxc-scc - fix build warnings on ARM64
  crypto: api - document missing stats member
  crypto: user - remove unused dump functions
  crypto: chelsio - Fix wrong error counter increments
  crypto: chelsio - Reset counters on cxgb4 Detach
  crypto: chelsio - Handle PCI shutdown event
  crypto: chelsio - cleanup:send addr as value in function argument
  crypto: chelsio - Use same value for both channel in single WR
  crypto: chelsio - Swap location of AAD and IV sent in WR
  crypto: chelsio - remove set but not used variable 'kctx_len'
  crypto: ux500 - Use proper enum in hash_set_dma_transfer
  crypto: ux500 - Use proper enum in cryp_set_dma_transfer
  crypto: aesni - Add scatter/gather avx stubs, and use them in C
  crypto: aesni - Introduce partial block macro
  ..
 2018-12-27 13:53:32 -08:00
Linus Torvalds e0c38a4d1f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 
Pull networking updates from David Miller:

 1) New ipset extensions for matching on destination MAC addresses, from
    Stefano Brivio.

 2) Add ipv4 ttl and tos, plus ipv6 flow label and hop limit offloads to
    nfp driver. From Stefano Brivio.

 3) Implement GRO for plain UDP sockets, from Paolo Abeni.

 4) Lots of work from Michał Mirosław to eliminate the VLAN_TAG_PRESENT
    bit so that we could support the entire vlan_tci value.

 5) Rework the IPSEC policy lookups to better optimize more usecases,
    from Florian Westphal.

 6) Infrastructure changes eliminating direct manipulation of SKB lists
    wherever possible, and to always use the appropriate SKB list
    helpers. This work is still ongoing...

 7) Lots of PHY driver and state machine improvements and
    simplifications, from Heiner Kallweit.

 8) Various TSO deferral refinements, from Eric Dumazet.

 9) Add ntuple filter support to aquantia driver, from Dmitry Bogdanov.

10) Batch dropping of XDP packets in tuntap, from Jason Wang.

11) Lots of cleanups and improvements to the r8169 driver from Heiner
    Kallweit, including support for ->xmit_more. This driver has been
    getting some much needed love since he started working on it.

12) Lots of new forwarding selftests from Petr Machata.

13) Enable VXLAN learning in mlxsw driver, from Ido Schimmel.

14) Packed ring support for virtio, from Tiwei Bie.

15) Add new Aquantia AQtion USB driver, from Dmitry Bezrukov.

16) Add XDP support to dpaa2-eth driver, from Ioana Ciocoi Radulescu.

17) Implement coalescing on TCP backlog queue, from Eric Dumazet.

18) Implement carrier change in tun driver, from Nicolas Dichtel.

19) Support msg_zerocopy in UDP, from Willem de Bruijn.

20) Significantly improve garbage collection of neighbor objects when
    the table has many PERMANENT entries, from David Ahern.

21) Remove egdev usage from nfp and mlx5, and remove the facility
    completely from the tree as it no longer has any users. From Oz
    Shlomo and others.

22) Add a NETDEV_PRE_CHANGEADDR so that drivers can veto the change and
    therefore abort the operation before the commit phase (which is the
    NETDEV_CHANGEADDR event). From Petr Machata.

23) Add indirect call wrappers to avoid retpoline overhead, and use them
    in the GRO code paths. From Paolo Abeni.

24) Add support for netlink FDB get operations, from Roopa Prabhu.

25) Support bloom filter in mlxsw driver, from Nir Dotan.

26) Add SKB extension infrastructure. This consolidates the handling of
    the auxiliary SKB data used by IPSEC and bridge netfilter, and is
    designed to support the needs to MPTCP which could be integrated in
    the future.

27) Lots of XDP TX optimizations in mlx5 from Tariq Toukan.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1845 commits)
  net: dccp: fix kernel crash on module load
  drivers/net: appletalk/cops: remove redundant if statement and mask
  bnx2x: Fix NULL pointer dereference in bnx2x_del_all_vlans() on some hw
  net/net_namespace: Check the return value of register_pernet_subsys()
  net/netlink_compat: Fix a missing check of nla_parse_nested
  ieee802154: lowpan_header_create check must check daddr
  net/mlx4_core: drop useless LIST_HEAD
  mlxsw: spectrum: drop useless LIST_HEAD
  net/mlx5e: drop useless LIST_HEAD
  iptunnel: Set tun_flags in the iptunnel_metadata_reply from src
  net/mlx5e: fix semicolon.cocci warnings
  staging: octeon: fix build failure with XFRM enabled
  net: Revert recent Spectre-v1 patches.
  can: af_can: Fix Spectre v1 vulnerability
  packet: validate address length if non-zero
  nfc: af_nfc: Fix Spectre v1 vulnerability
  phonet: af_phonet: Fix Spectre v1 vulnerability
  net: core: Fix Spectre v1 vulnerability
  net: minor cleanup in skb_ext_add()
  net: drop the unused helper skb_ext_get()
  ...
 2018-12-27 13:04:52 -08:00