Commit Graph

34656 Commits

Author SHA1 Message Date
Linus Torvalds 6734e20e39 arm64 updates for 5.10
- Userspace support for the Memory Tagging Extension introduced by Armv8.5.
   Kernel support (via KASAN) is likely to follow in 5.11.
 
 - Selftests for MTE, Pointer Authentication and FPSIMD/SVE context
   switching.
 
 - Fix and subsequent rewrite of our Spectre mitigations, including the
   addition of support for PR_SPEC_DISABLE_NOEXEC.
 
 - Support for the Armv8.3 Pointer Authentication enhancements.
 
 - Support for ASID pinning, which is required when sharing page-tables with
   the SMMU.
 
 - MM updates, including treating flush_tlb_fix_spurious_fault() as a no-op.
 
 - Perf/PMU driver updates, including addition of the ARM CMN PMU driver and
   also support to handle CPU PMU IRQs as NMIs.
 
 - Allow prefetchable PCI BARs to be exposed to userspace using normal
   non-cacheable mappings.
 
 - Implementation of ARCH_STACKWALK for unwinding.
 
 - Improve reporting of unexpected kernel traps due to BPF JIT failure.
 
 - Improve robustness of user-visible HWCAP strings and their corresponding
   numerical constants.
 
 - Removal of TEXT_OFFSET.
 
 - Removal of some unused functions, parameters and prototypes.
 
 - Removal of MPIDR-based topology detection in favour of firmware
   description.
 
 - Cleanups to handling of SVE and FPSIMD register state in preparation
   for potential future optimisation of handling across syscalls.
 
 - Cleanups to the SDEI driver in preparation for support in KVM.
 
 - Miscellaneous cleanups and refactoring work.
 -----BEGIN PGP SIGNATURE-----
 
 iQFEBAABCgAuFiEEPxTL6PPUbjXGY88ct6xw3ITBYzQFAl+AUXMQHHdpbGxAa2Vy
 bmVsLm9yZwAKCRC3rHDchMFjNFc1B/4q2Kabe+pPu7s1f58Q+OTaEfqcr3F1qh27
 F1YpFZUYxg0GPfPsFrnbJpo5WKo7wdR9ceI9yF/GHjs7A/MSoQJis3pG6SlAd9c0
 nMU5tCwhg9wfq6asJtl0/IPWem6cqqhdzC6m808DjeHuyi2CCJTt0vFWH3OeHEhG
 cfmLfaSNXOXa/MjEkT8y1AXJ/8IpIpzkJeCRA1G5s18PXV9Kl5bafIo9iqyfKPLP
 0rJljBmoWbzuCSMc81HmGUQI4+8KRp6HHhyZC/k0WEVgj3LiumT7am02bdjZlTnK
 BeNDKQsv2Jk8pXP2SlrI3hIUTz0bM6I567FzJEokepvTUzZ+CVBi
 =9J8H
 -----END PGP SIGNATURE-----

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "There's quite a lot of code here, but much of it is due to the
  addition of a new PMU driver as well as some arm64-specific selftests
  which is an area where we've traditionally been lagging a bit.

  In terms of exciting features, this includes support for the Memory
  Tagging Extension which narrowly missed 5.9, hopefully allowing
  userspace to run with use-after-free detection in production on CPUs
  that support it. Work is ongoing to integrate the feature with KASAN
  for 5.11.

  Another change that I'm excited about (assuming they get the hardware
  right) is preparing the ASID allocator for sharing the CPU page-table
  with the SMMU. Those changes will also come in via Joerg with the
  IOMMU pull.

  We do stray outside of our usual directories in a few places, mostly
  due to core changes required by MTE. Although much of this has been
  Acked, there were a couple of places where we unfortunately didn't get
  any review feedback.

  Other than that, we ran into a handful of minor conflicts in -next,
  but nothing that should post any issues.

  Summary:

   - Userspace support for the Memory Tagging Extension introduced by
     Armv8.5. Kernel support (via KASAN) is likely to follow in 5.11.

   - Selftests for MTE, Pointer Authentication and FPSIMD/SVE context
     switching.

   - Fix and subsequent rewrite of our Spectre mitigations, including
     the addition of support for PR_SPEC_DISABLE_NOEXEC.

   - Support for the Armv8.3 Pointer Authentication enhancements.

   - Support for ASID pinning, which is required when sharing
     page-tables with the SMMU.

   - MM updates, including treating flush_tlb_fix_spurious_fault() as a
     no-op.

   - Perf/PMU driver updates, including addition of the ARM CMN PMU
     driver and also support to handle CPU PMU IRQs as NMIs.

   - Allow prefetchable PCI BARs to be exposed to userspace using normal
     non-cacheable mappings.

   - Implementation of ARCH_STACKWALK for unwinding.

   - Improve reporting of unexpected kernel traps due to BPF JIT
     failure.

   - Improve robustness of user-visible HWCAP strings and their
     corresponding numerical constants.

   - Removal of TEXT_OFFSET.

   - Removal of some unused functions, parameters and prototypes.

   - Removal of MPIDR-based topology detection in favour of firmware
     description.

   - Cleanups to handling of SVE and FPSIMD register state in
     preparation for potential future optimisation of handling across
     syscalls.

   - Cleanups to the SDEI driver in preparation for support in KVM.

   - Miscellaneous cleanups and refactoring work"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (148 commits)
  Revert "arm64: initialize per-cpu offsets earlier"
  arm64: random: Remove no longer needed prototypes
  arm64: initialize per-cpu offsets earlier
  kselftest/arm64: Check mte tagged user address in kernel
  kselftest/arm64: Verify KSM page merge for MTE pages
  kselftest/arm64: Verify all different mmap MTE options
  kselftest/arm64: Check forked child mte memory accessibility
  kselftest/arm64: Verify mte tag inclusion via prctl
  kselftest/arm64: Add utilities and a test to validate mte memory
  perf: arm-cmn: Fix conversion specifiers for node type
  perf: arm-cmn: Fix unsigned comparison to less than zero
  arm64: dbm: Invalidate local TLB when setting TCR_EL1.HD
  arm64: mm: Make flush_tlb_fix_spurious_fault() a no-op
  arm64: Add support for PR_SPEC_DISABLE_NOEXEC prctl() option
  arm64: Pull in task_stack_page() to Spectre-v4 mitigation code
  KVM: arm64: Allow patching EL2 vectors even with KASLR is not enabled
  arm64: Get rid of arm64_ssbd_state
  KVM: arm64: Convert ARCH_WORKAROUND_2 to arm64_get_spectre_v4_state()
  KVM: arm64: Get rid of kvm_arm_have_ssbd()
  KVM: arm64: Simplify handling of ARCH_WORKAROUND_2
  ...
2020-10-12 10:00:51 -07:00
Daniel Jordan fdf09ab887 module: statically initialize init section freeing data
Corentin hit the following workqueue warning when running with
CRYPTO_MANAGER_EXTRA_TESTS:

  WARNING: CPU: 2 PID: 147 at kernel/workqueue.c:1473 __queue_work+0x3b8/0x3d0
  Modules linked in: ghash_generic
  CPU: 2 PID: 147 Comm: modprobe Not tainted
      5.6.0-rc1-next-20200214-00068-g166c9264f0b1-dirty #545
  Hardware name: Pine H64 model A (DT)
  pc : __queue_work+0x3b8/0x3d0
  Call trace:
   __queue_work+0x3b8/0x3d0
   queue_work_on+0x6c/0x90
   do_init_module+0x188/0x1f0
   load_module+0x1d00/0x22b0

I wasn't able to reproduce on x86 or rpi 3b+.

This is

  WARN_ON(!list_empty(&work->entry))

from __queue_work(), and it happens because the init_free_wq work item
isn't initialized in time for a crypto test that requests the gcm
module.  Some crypto tests were recently moved earlier in boot as
explained in commit c4741b2305 ("crypto: run initcalls for generic
implementations earlier"), which went into mainline less than two weeks
before the Fixes commit.

Avoid the warning by statically initializing init_free_wq and the
corresponding llist.

Link: https://lore.kernel.org/lkml/20200217204803.GA13479@Red/
Fixes: 1a7b7d9220 ("modules: Use vmalloc special flag")
Reported-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Tested-on: sun50i-h6-pine-h64
Tested-on: imx8mn-ddr4-evk
Tested-on: sun50i-a64-bananapi-m64
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2020-10-12 18:27:00 +02:00
Jiri Olsa f91072ed1b perf/core: Fix race in the perf_mmap_close() function
There's a possible race in perf_mmap_close() when checking ring buffer's
mmap_count refcount value. The problem is that the mmap_count check is
not atomic because we call atomic_dec() and atomic_read() separately.

  perf_mmap_close:
  ...
   atomic_dec(&rb->mmap_count);
   ...
   if (atomic_read(&rb->mmap_count))
      goto out_put;

   <ring buffer detach>
   free_uid

out_put:
  ring_buffer_put(rb); /* could be last */

The race can happen when we have two (or more) events sharing same ring
buffer and they go through atomic_dec() and then they both see 0 as refcount
value later in atomic_read(). Then both will go on and execute code which
is meant to be run just once.

The code that detaches ring buffer is probably fine to be executed more
than once, but the problem is in calling free_uid(), which will later on
demonstrate in related crashes and refcount warnings, like:

  refcount_t: addition on 0; use-after-free.
  ...
  RIP: 0010:refcount_warn_saturate+0x6d/0xf
  ...
  Call Trace:
  prepare_creds+0x190/0x1e0
  copy_creds+0x35/0x172
  copy_process+0x471/0x1a80
  _do_fork+0x83/0x3a0
  __do_sys_wait4+0x83/0x90
  __do_sys_clone+0x85/0xa0
  do_syscall_64+0x5b/0x1e0
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Using atomic decrease and check instead of separated calls.

Tested-by: Michael Petlan <mpetlan@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Wade Mealing <wmealing@redhat.com>
Fixes: 9bb5d40cd9 ("perf: Fix mmap() accounting hole");
Link: https://lore.kernel.org/r/20200916115311.GE2301783@krava
2020-10-12 13:24:26 +02:00
Petr Mladek 70333f4ff9 Merge branch 'printk-rework' into for-linus 2020-10-12 13:01:37 +02:00
Thomas Gleixner 863bae1fbc irqchip updates for Linux 5.10
Core changes:
 - Allow irq retriggering to follow a hierarchy
 - Allow interrupt hierarchies to be trimmed at allocation time
 - Allow interrupts to be hidden from /proc/interrupts (IPIs)
 - Introduce stub for set_handle_irq() when !GENERIC_IRQ_MULTI_HANDLER
 - New per-cpu IPI handling flow
 
 Architecture changes:
 - Move arm/arm64 IPI handling to the core interrupt code, removing
   the home brewed accounting
 
 Driver updates:
 - New driver for the MStar (and more recently Mediatek) platforms
 - New driver for the Actions Owl SIRQ controller
 - New driver for the TI PRUSS infrastructure
 - Wake-up support for the Qualcomm PDC controller
 - Primary interrupt controller support for the Designware APB ICTL
 - Convert the IPI code for GIC, GICv3, hip04, armada-270-xp and bcm2836
   to using standard interrupts
 - Improve GICv3 pseudo-NMI support to deal with both non-secure and secure
   priorities on arm64
 - Convert the GIC/GICv3 drivers to using HW-based irq retrigger
 - A sprinkling of dev_err_probe() conversion
 - A set of NVIDIA Tegra fixes for interrupt hierarchy corruption
 - A reset fix for the Loongson HTVEC driver
 - A couple of error handling fixes in the TI SCI drivers
 -----BEGIN PGP SIGNATURE-----
 
 iQJDBAABCgAtFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAl+BpbUPHG1hekBrZXJu
 ZWwub3JnAAoJECPQ0LrRPXpDjDsP/jzeIuPM1pexLfPiYqHUNuR3HdJGTtUzsWnm
 +zpxDrqLgjtecBHRCEWs/GVOE1h+VtmuW1s9u2V6PEnOapmevwAbKh36WLoRj1MA
 Pvk+wmy7MrgF/fpycIb0rl8qTcwdjp5W7MXBCdYy0TwGV0VQO2qio+KMDBDfZC9G
 yJRNH2DMFto+uJu0o1XVeS2JzaYZ1J57yVHYgpV6cOCrAN9c921dFTgfE2oUd1I8
 p4lIQ7vUbQpBtyYkrHHn5voWqR9RziZGSUgkm8HCxyWODYm57stFQ406OkCmU0Uc
 MbBasfMLXeDE0Go6gdPkZOeTLGTq6RKOxvYNeGO5Q5USQo5zjCppxosf2woj6rUi
 PLsFh26CJ5pIkBdlCV/PDWvxZnAw8zQ8me3Q9Hn9gMo3x7k85RH25MFZqHPStMcw
 rXI5U7kn4NQxLk9oZ1J4Hg0S0eeEysywCTsT19avLJT1gBjrp7k1f3stXiN/4F1e
 EPhX9+UQHYTyr9AMXYVPReEfQPmpMrKzr3Oq+YJeqQhj3qQt/3Siw9J3IRMnU/1+
 zm9KP0ehnCeZuPrIbH/m+JFOnw0LscflQ9a0GuIsXnGsBwvmBCP/PENWFuOJjJrH
 GEq6UlaEg8JM4KDcEfE26C3Sk+jjiHmqSzfaIkbeYMBCIGyVj9n2slxmJBOLTRNb
 rWoCk+BI
 =dfh2
 -----END PGP SIGNATURE-----

Merge tag 'irqchip-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core

Pull irqchip updates from Marc Zyngier:

 Core changes:

  - Allow irq retriggering to follow a hierarchy
  - Allow interrupt hierarchies to be trimmed at allocation time
  - Allow interrupts to be hidden from /proc/interrupts (IPIs)
  - Introduce stub for set_handle_irq() when !GENERIC_IRQ_MULTI_HANDLER
  - New per-cpu IPI handling flow

 Architecture changes:
  - Move arm/arm64 IPI handling to the core interrupt code, removing
    the home brewed accounting

 Driver updates:
 - New driver for the MStar (and more recently Mediatek) platforms
 - New driver for the Actions Owl SIRQ controller
 - New driver for the TI PRUSS infrastructure
 - Wake-up support for the Qualcomm PDC controller
 - Primary interrupt controller support for the Designware APB ICTL
 - Convert the IPI code for GIC, GICv3, hip04, armada-270-xp and bcm2836
   to using standard interrupts
 - Improve GICv3 pseudo-NMI support to deal with both non-secure and secure
   priorities on arm64
 - Convert the GIC/GICv3 drivers to using HW-based irq retrigger
 - A sprinkling of dev_err_probe() conversion
 - A set of NVIDIA Tegra fixes for interrupt hierarchy corruption
 - A reset fix for the Loongson HTVEC driver
 - A couple of error handling fixes in the TI SCI drivers
2020-10-11 19:53:13 +02:00
Linus Torvalds aa5c3a2911 Fix a bug that can cause a lockup if a CPU is offline.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAl+CuIsRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1hHiQ//SGk+Pz9RCxUiW6AK40Yxvl0jjqWdpYQY
 y0I6HaI1NVNLXVO7m65zXUr/23jxxxD1Ysst0SxM/v1hli4PTmzIKqcr1mGgwwn2
 9miAQHUNn5wd6RCw9lYMXbkIqhRfd2Zm376Ydia/620N+MjUfO5lroLpK1OyF4Q9
 jwsSWnwJRsytXvC5Qj7eRuRCxYXDk+KgpFBU8RspXI7I+UdzPL0mBJm1XIif38or
 ueID3iHTiNErXaHGuoDeGQJAawUFS+Y44BAzsWOdScKLeX4PwPzK5QimGBnoTfGb
 Jw3rvn2zZS26GUPtVep4QRFPxd41K6G3KyAHqUqY/kkzzIPbO+pKb/8CIRSkVOyB
 pFsdRZtO2+bLnThckZKxlJBWrYBSN72koOvsIICPOcovsbLcr/U6mqKZYjqyw3VN
 NXn90nzkghATRGZkYXpF/I+1cgbtqOHf2EoTIq+pKGsahmqiy4s6twr4SLCqLxbF
 JLa+oUcECfywTBHJbkc3/V7MQ9YPi3eCNTcOr6DQBXoX8MqL2oPR6ZNK6OFNolz3
 sidfs72+jtWLnAKbd34KueZioccK4jvY7bnrcrG70bUsO9nP2Zj6qcq1iijd8V5f
 o7xtFG6DrhEGwLCvHbtw9oA6Iqd1c+5RT7TkV+1JTFj7voE2/NYXpwRRh6uSZ/vO
 Y0/q66Hmn7E=
 =IeZB
 -----END PGP SIGNATURE-----

Merge tag 'perf-urgent-2020-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fix from Ingo Molnar:
 "Fix an error handling bug that can cause a lockup if a CPU is offline
  (doh ...)"

* tag 'perf-urgent-2020-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix task_function_call() error handling
2020-10-11 10:43:37 -07:00
Daniel Borkmann 4a8f87e60f bpf: Allow for map-in-map with dynamic inner array map entries
Recent work in f4d0525921 ("bpf: Add map_meta_equal map ops") and 134fede4ee
("bpf: Relax max_entries check for most of the inner map types") added support
for dynamic inner max elements for most map-in-map types. Exceptions were maps
like array or prog array where the map_gen_lookup() callback uses the maps'
max_entries field as a constant when emitting instructions.

We recently implemented Maglev consistent hashing into Cilium's load balancer
which uses map-in-map with an outer map being hash and inner being array holding
the Maglev backend table for each service. This has been designed this way in
order to reduce overall memory consumption given the outer hash map allows to
avoid preallocating a large, flat memory area for all services. Also, the
number of service mappings is not always known a-priori.

The use case for dynamic inner array map entries is to further reduce memory
overhead, for example, some services might just have a small number of back
ends while others could have a large number. Right now the Maglev backend table
for small and large number of backends would need to have the same inner array
map entries which adds a lot of unneeded overhead.

Dynamic inner array map entries can be realized by avoiding the inlined code
generation for their lookup. The lookup will still be efficient since it will
be calling into array_map_lookup_elem() directly and thus avoiding retpoline.
The patch adds a BPF_F_INNER_MAP flag to map creation which therefore skips
inline code generation and relaxes array_map_meta_equal() check to ignore both
maps' max_entries. This also still allows to have faster lookups for map-in-map
when BPF_F_INNER_MAP is not specified and hence dynamic max_entries not needed.

Example code generation where inner map is dynamic sized array:

  # bpftool p d x i 125
  int handle__sys_enter(void * ctx):
  ; int handle__sys_enter(void *ctx)
     0: (b4) w1 = 0
  ; int key = 0;
     1: (63) *(u32 *)(r10 -4) = r1
     2: (bf) r2 = r10
  ;
     3: (07) r2 += -4
  ; inner_map = bpf_map_lookup_elem(&outer_arr_dyn, &key);
     4: (18) r1 = map[id:468]
     6: (07) r1 += 272
     7: (61) r0 = *(u32 *)(r2 +0)
     8: (35) if r0 >= 0x3 goto pc+5
     9: (67) r0 <<= 3
    10: (0f) r0 += r1
    11: (79) r0 = *(u64 *)(r0 +0)
    12: (15) if r0 == 0x0 goto pc+1
    13: (05) goto pc+1
    14: (b7) r0 = 0
    15: (b4) w6 = -1
  ; if (!inner_map)
    16: (15) if r0 == 0x0 goto pc+6
    17: (bf) r2 = r10
  ;
    18: (07) r2 += -4
  ; val = bpf_map_lookup_elem(inner_map, &key);
    19: (bf) r1 = r0                               | No inlining but instead
    20: (85) call array_map_lookup_elem#149280     | call to array_map_lookup_elem()
  ; return val ? *val : -1;                        | for inner array lookup.
    21: (15) if r0 == 0x0 goto pc+1
  ; return val ? *val : -1;
    22: (61) r6 = *(u32 *)(r0 +0)
  ; }
    23: (bc) w0 = w6
    24: (95) exit

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201010234006.7075-4-daniel@iogearbox.net
2020-10-11 10:21:04 -07:00
Marc Zyngier 408f110ef6 Merge branch 'irq/tegra-pmc' into irq/irqchip-next
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-10-10 12:16:24 +01:00
Marc Zyngier 5556797662 genirq/irqdomain: Allow partial trimming of irq_data hierarchy
It appears that some HW is ugly enough that not all the interrupts
connected to a particular interrupt controller end up with the same
hierarchy depth (some of them are terminated early). This leaves
the irqchip hacker with only two choices, both equally bad:

- create discrete domain chains, one for each "hierarchy depth",
  which is very hard to maintain

- create fake hierarchy levels for the shallow paths, leading
  to all kind of problems (what are the safe hwirq values for these
  fake levels?)

Implement the ability to cut short a single interrupt hierarchy
from a level marked as being disconnected by using the new
irq_domain_disconnect_hierarchy() helper.

The irqdomain allocation code will then perform the trimming

Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-10-10 12:12:10 +01:00
Yonghong Song 5689d49b71 bpf: Track spill/fill of bounded scalars.
Under register pressure the llvm may spill registers with bounds into the stack.
The verifier has to track them through spill/fill otherwise many kinds of bound
errors will be seen. The spill/fill of induction variables was already
happening. This patch extends this logic from tracking spill/fill of a constant
into any bounded register. There is no need to track spill/fill of unbounded,
since no new information will be retrieved from the stack during register fill.

Though extra stack difference could cause state pruning to be less effective, no
adverse affects were seen from this patch on selftests and on cilium programs.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20201009011240.48506-3-alexei.starovoitov@gmail.com
2020-10-09 22:03:06 +02:00
Alexei Starovoitov 75748837b7 bpf: Propagate scalar ranges through register assignments.
The llvm register allocator may use two different registers representing the
same virtual register. In such case the following pattern can be observed:
1047: (bf) r9 = r6
1048: (a5) if r6 < 0x1000 goto pc+1
1050: ...
1051: (a5) if r9 < 0x2 goto pc+66
1052: ...
1053: (bf) r2 = r9 /* r2 needs to have upper and lower bounds */

This is normal behavior of greedy register allocator.
The slides 137+ explain why regalloc introduces such register copy:
http://llvm.org/devmtg/2018-04/slides/Yatsina-LLVM%20Greedy%20Register%20Allocator.pdf
There is no way to tell llvm 'not to do this'.
Hence the verifier has to recognize such patterns.

In order to track this information without backtracking allocate ID
for scalars in a similar way as it's done for find_good_pkt_pointers().

When the verifier encounters r9 = r6 assignment it will assign the same ID
to both registers. Later if either register range is narrowed via conditional
jump propagate the register state into the other register.

Clear register ID in adjust_reg_min_max_vals() for any alu instruction. The
register ID is ignored for scalars in regsafe() and doesn't affect state
pruning. mark_reg_unknown() clears the ID. It's used to process call, endian
and other instructions. Hence ID is explicitly cleared only in
adjust_reg_min_max_vals() and in 32-bit mov.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20201009011240.48506-2-alexei.starovoitov@gmail.com
2020-10-09 22:03:06 +02:00
Ingo Molnar d6c4c11348 Merge branch 'kcsan' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/core
Pull KCSAN updates for v5.10 from Paul E. McKenney:

 - Improve kernel messages.

 - Be more permissive with bitops races under KCSAN_ASSUME_PLAIN_WRITES_ATOMIC=y.

 - Optimize debugfs stat counters.

 - Introduce the instrument_*read_write() annotations, to provide a
   finer description of certain ops - using KCSAN's compound instrumentation.
   Use them for atomic RNW and bitops, where appropriate.
   Doing this might find new races.
   (Depends on the compiler having tsan-compound-read-before-write=1 support.)

 - Support atomic built-ins, which will help certain architectures, such as s390.

 - Misc enhancements and smaller fixes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-10-09 08:56:02 +02:00
Ingo Molnar e705d39796 Merge branch 'locking/urgent' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-10-09 08:55:17 +02:00
Peter Zijlstra 4d004099a6 lockdep: Fix lockdep recursion
Steve reported that lockdep_assert*irq*(), when nested inside lockdep
itself, will trigger a false-positive.

One example is the stack-trace code, as called from inside lockdep,
triggering tracing, which in turn calls RCU, which then uses
lockdep_assert_irqs_disabled().

Fixes: a21ee6055c ("lockdep: Change hardirq{s_enabled,_context} to per-cpu variables")
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-10-09 08:53:30 +02:00
Peter Zijlstra 2bb8945bcc lockdep: Fix usage_traceoverflow
Basically print_lock_class_header()'s for loop is out of sync with the
the size of of ->usage_traces[].

Also clean things up a bit while at it, to avoid such mishaps in the future.

Fixes: 23870f1227 ("locking/lockdep: Fix "USED" <- "IN-NMI" inversions")
Reported-by: Qian Cai <cai@redhat.com>
Debugged-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Qian Cai <cai@redhat.com>
Link: https://lkml.kernel.org/r/20200930094937.GE2651@hirez.programming.kicks-ass.net
2020-10-09 08:53:08 +02:00
Ingo Molnar b36c830f8c Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull v5.10 RCU changes from Paul E. McKenney:

- Debugging for smp_call_function().

- Strict grace periods for KASAN.  The point of this series is to find
  RCU-usage bugs, so the corresponding new RCU_STRICT_GRACE_PERIOD
  Kconfig option depends on both DEBUG_KERNEL and RCU_EXPERT, and is
  further disabled by dfefault.  Finally, the help text includes
  a goodly list of scary caveats.

- New smp_call_function() torture test.

- Torture-test updates.

- Documentation updates.

- Miscellaneous fixes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-10-09 08:21:56 +02:00
Kajol Jain 6d6b8b9f4f perf: Fix task_function_call() error handling
The error handling introduced by commit:

  2ed6edd33a ("perf: Add cond_resched() to task_function_call()")

looses any return value from smp_call_function_single() that is not
{0, -EINVAL}. This is a problem because it will return -EXNIO when the
target CPU is offline. Worse, in that case it'll turn into an infinite
loop.

Fixes: 2ed6edd33a ("perf: Add cond_resched() to task_function_call()")
Reported-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Barret Rhoden <brho@google.com>
Tested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: https://lkml.kernel.org/r/20200827064732.20860-1-kjain@linux.ibm.com
2020-10-09 08:18:33 +02:00
Jakub Kicinski 9d49aea13f Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Small conflict around locking in rxrpc_process_event() -
channel_lock moved to bundle in next, while state lock
needs _bh() from net.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-08 15:44:50 -07:00
Linus Torvalds 6288c1d802 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
 "One more set of fixes from the networking tree:

   - add missing input validation in nl80211_del_key(), preventing
     out-of-bounds access

   - last minute fix / improvement of a MRP netlink (uAPI) interface
     introduced in 5.9 (current) release

   - fix "unresolved symbol" build error under CONFIG_NET w/o
     CONFIG_INET due to missing tcp_timewait_sock and inet_timewait_sock
     BTF.

   - fix 32 bit sub-register bounds tracking in the bpf verifier for OR
     case

   - tcp: fix receive window update in tcp_add_backlog()

   - openvswitch: handle DNAT tuple collision in conntrack-related code

   - r8169: wait for potential PHY reset to finish after applying a FW
     file, avoiding unexpected PHY behaviour and failures later on

   - mscc: fix tail dropping watermarks for Ocelot switches

   - avoid use-after-free in macsec code after a call to the GRO layer

   - avoid use-after-free in sctp error paths

   - add a device id for Cellient MPL200 WWAN card

   - rxrpc fixes:
      - fix the xdr encoding of the contents read from an rxrpc key
      - fix a BUG() for a unsupported encoding type.
      - fix missing _bh lock annotations.
      - fix acceptance handling for an incoming call where the incoming
        call is encrypted.
      - the server token keyring isn't network namespaced - it belongs
        to the server, so there's no need. Namespacing it means that
        request_key() fails to find it.
      - fix a leak of the server keyring"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (21 commits)
  net: usb: qmi_wwan: add Cellient MPL200 card
  macsec: avoid use-after-free in macsec_handle_frame()
  r8169: consider that PHY reset may still be in progress after applying firmware
  openvswitch: handle DNAT tuple collision
  sctp: fix sctp_auth_init_hmacs() error path
  bridge: Netlink interface fix.
  net: wireless: nl80211: fix out-of-bounds access in nl80211_del_key()
  bpf: Fix scalar32_min_max_or bounds tracking
  tcp: fix receive window update in tcp_add_backlog()
  net: usb: rtl8150: set random MAC address when set_ethernet_addr() fails
  mptcp: more DATA FIN fixes
  net: mscc: ocelot: warn when encoding an out-of-bounds watermark value
  net: mscc: ocelot: divide watermark value by 60 when writing to SYS_ATOP
  net: qrtr: ns: Fix the incorrect usage of rcu_read_lock()
  rxrpc: Fix server keyring leak
  rxrpc: The server keyring isn't network-namespaced
  rxrpc: Fix accept on a connection that need securing
  rxrpc: Fix some missing _bh annotations on locking conn->state_lock
  rxrpc: Downgrade the BUG() for unsupported token type in rxrpc_read()
  rxrpc: Fix rxkad token xdr encoding
  ...
2020-10-08 14:11:21 -07:00
Jann Horn dfe719fef0 seccomp: Make duplicate listener detection non-racy
Currently, init_listener() tries to prevent adding a filter with
SECCOMP_FILTER_FLAG_NEW_LISTENER if one of the existing filters already
has a listener. However, this check happens without holding any lock that
would prevent another thread from concurrently installing a new filter
(potentially with a listener) on top of the ones we already have.

Theoretically, this is also a data race: The plain load from
current->seccomp.filter can race with concurrent writes to the same
location.

Fix it by moving the check into the region that holds the siglock to guard
against concurrent TSYNC.

(The "Fixes" tag points to the commit that introduced the theoretical
data race; concurrent installation of another filter with TSYNC only
became possible later, in commit 51891498f2 ("seccomp: allow TSYNC and
USER_NOTIF together").)

Fixes: 6a21cc50f0 ("seccomp: add a return code to trap to userspace")
Reviewed-by: Tycho Andersen <tycho@tycho.pizza>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201005014401.490175-1-jannh@google.com
2020-10-08 13:17:47 -07:00
Steven Rostedt (VMware) 848183553e tracing: Fix synthetic print fmt check for use of __get_str()
A cut and paste error had the check to use __get_str() test "is_dynamic"
twice, instead of checking "is_string && is_dynamic".

Link: https://lore.kernel.org/r/d34dccd5-96ba-a2d9-46ea-de8807525deb@canonical.com

Reported-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-08 15:29:07 -04:00
Sudip Mukherjee 43aa422c0c tracing: Remove a pointless assignment
The variable 'len' has been assigned a value but is not used after that.
So, remove the assignement.

Link: https://lkml.kernel.org/r/20200930184303.22896-1-sudipm.mukherjee@gmail.com

Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-08 15:29:06 -04:00
Steven Rostedt (VMware) 7ba031e8b7 ftrace: Format variable declarations of ftrace_allocate_records
I hate when unrelated variables are declared on the same line.
Split them.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-08 15:29:06 -04:00
Wei Yang b40c6eabfc ftrace: Simplify the calculation of page number for ftrace_page->records
Based on the following two reasones, we could simplify the calculation:

  - If the number after roundup count is not power of 2, we would
    definitely have more than 1 empty page with a higher order.
  - get_count_order() just return current order, so one lower order
    could meet the requirement.

The calculation could be simplified by lower one order level when pages
are not power of 2.

Link: https://lkml.kernel.org/r/20200831031104.23322-5-richard.weiyang@linux.alibaba.com

Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-08 15:29:06 -04:00
Steven Rostedt (VMware) be49313273 ftrace: Simplify the hash calculation
No need to add a check to subtract the number of bits if bits is zero after
fls(). Just divide the size by two before calling it. This does give the
same answer for size of 0 and 1, but that's fine.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-08 15:29:06 -04:00
Wei Yang 59e65b3358 ftrace: Use fls() to get the bits for dup_hash()
The effect here is to get the number of bits, lets use fls() to do
this job.

Link: https://lkml.kernel.org/r/20200831031104.23322-3-richard.weiyang@linux.alibaba.com

Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-08 15:29:06 -04:00
Steven Rostedt (VMware) 8db4d6bfbb tracing: Change synthetic event string format to limit printed length
Change the format for printing synthetic field strings to limit the
length of the string printed even if it's not correctly terminated.

Link: https://lore.kernel.org/r/20201002210036.0200371b@oasis.local.home
Link: https://lkml.kernel.org/r/b6bdb34e70d970e8026daa3503db6b8e5cdad524.1601848695.git.zanussi@kernel.org

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-08 15:29:06 -04:00
Tom Zanussi 1bc36bd4a8 tracing: Add README information for synthetic_events file
Add an entry with a basic description of events/synthetic_events along
with a simple example.

Link: https://lkml.kernel.org/r/3c7f178cf95aaeebc01eda7d95600dd937233eb7.1601848695.git.zanussi@kernel.org

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-08 15:28:14 -04:00
Jakub Kicinski cfe90f4980 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2020-10-08

The main changes are:

1) Fix "unresolved symbol" build error under CONFIG_NET w/o CONFIG_INET due
   to missing tcp_timewait_sock and inet_timewait_sock BTF, from Yonghong Song.

2) Fix 32 bit sub-register bounds tracking for OR case, from Daniel Borkmann.
====================

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-08 12:05:37 -07:00
Daniel Borkmann 5b9fbeb75b bpf: Fix scalar32_min_max_or bounds tracking
Simon reported an issue with the current scalar32_min_max_or() implementation.
That is, compared to the other 32 bit subreg tracking functions, the code in
scalar32_min_max_or() stands out that it's using the 64 bit registers instead
of 32 bit ones. This leads to bounds tracking issues, for example:

  [...]
  8: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm
  8: (79) r1 = *(u64 *)(r0 +0)
   R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm
  9: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm
  9: (b7) r0 = 1
  10: R0_w=inv1 R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm
  10: (18) r2 = 0x600000002
  12: R0_w=inv1 R1_w=inv(id=0) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  12: (ad) if r1 < r2 goto pc+1
   R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  13: R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  13: (95) exit
  14: R0_w=inv1 R1_w=inv(id=0,umax_value=25769803777,var_off=(0x0; 0x7ffffffff)) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  14: (25) if r1 > 0x0 goto pc+1
   R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  15: R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  15: (95) exit
  16: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=25769803777,var_off=(0x0; 0x77fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  16: (47) r1 |= 0
  17: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=32212254719,var_off=(0x1; 0x700000000),s32_max_value=1,u32_max_value=1) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  [...]

The bound tests on the map value force the upper unsigned bound to be 25769803777
in 64 bit (0b11000000000000000000000000000000001) and then lower one to be 1. By
using OR they are truncated and thus result in the range [1,1] for the 32 bit reg
tracker. This is incorrect given the only thing we know is that the value must be
positive and thus 2147483647 (0b1111111111111111111111111111111) at max for the
subregs. Fix it by using the {u,s}32_{min,max}_value vars instead. This also makes
sense, for example, for the case where we update dst_reg->s32_{min,max}_value in
the else branch we need to use the newly computed dst_reg->u32_{min,max}_value as
we know that these are positive. Previously, in the else branch the 64 bit values
of umin_value=1 and umax_value=32212254719 were used and latter got truncated to
be 1 as upper bound there. After the fix the subreg range is now correct:

  [...]
  8: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm
  8: (79) r1 = *(u64 *)(r0 +0)
   R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm
  9: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm
  9: (b7) r0 = 1
  10: R0_w=inv1 R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm
  10: (18) r2 = 0x600000002
  12: R0_w=inv1 R1_w=inv(id=0) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  12: (ad) if r1 < r2 goto pc+1
   R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  13: R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  13: (95) exit
  14: R0_w=inv1 R1_w=inv(id=0,umax_value=25769803777,var_off=(0x0; 0x7ffffffff)) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  14: (25) if r1 > 0x0 goto pc+1
   R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  15: R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  15: (95) exit
  16: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=25769803777,var_off=(0x0; 0x77fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  16: (47) r1 |= 0
  17: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=32212254719,var_off=(0x0; 0x77fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  [...]

Fixes: 3f50f132d8 ("bpf: Verifier, do explicit ALU32 bounds tracking")
Reported-by: Simon Scannell <scannell.smn@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
2020-10-08 11:02:53 +02:00
Yonghong Song ebfb4d40ed bpf: Fix build failure for kernel/trace/bpf_trace.c with CONFIG_NET=n
When CONFIG_NET is not defined, I hit the following build error:
    kernel/trace/bpf_trace.o:(.rodata+0x110): undefined reference to `bpf_prog_test_run_raw_tp'

Commit 1b4d60ec16 ("bpf: Enable BPF_PROG_TEST_RUN for raw_tracepoint")
added test_run support for raw_tracepoint in /kernel/trace/bpf_trace.c.
But the test_run function bpf_prog_test_run_raw_tp is defined in
net/bpf/test_run.c, only available with CONFIG_NET=y.

Adding a CONFIG_NET guard for
    .test_run = bpf_prog_test_run_raw_tp;
fixed the above build issue.

Fixes: 1b4d60ec16 ("bpf: Enable BPF_PROG_TEST_RUN for raw_tracepoint")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201007062933.3425899-1-yhs@fb.com
2020-10-07 10:56:46 -07:00
Randy Dunlap 49a2a4d416 kernel/bpf/verifier: Fix build when NET is not enabled
Fix build errors in kernel/bpf/verifier.c when CONFIG_NET is
not enabled.

../kernel/bpf/verifier.c:3995:13: error: ‘btf_sock_ids’ undeclared here (not in a function); did you mean ‘bpf_sock_ops’?
  .btf_id = &btf_sock_ids[BTF_SOCK_TYPE_SOCK_COMMON],

../kernel/bpf/verifier.c:3995:26: error: ‘BTF_SOCK_TYPE_SOCK_COMMON’ undeclared here (not in a function); did you mean ‘PTR_TO_SOCK_COMMON’?
  .btf_id = &btf_sock_ids[BTF_SOCK_TYPE_SOCK_COMMON],

Fixes: 1df8f55a37 ("bpf: Enable bpf_skc_to_* sock casting helper to networking prog type")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20201007021613.13646-1-rdunlap@infradead.org
2020-10-07 10:53:43 -07:00
Rafael J. Wysocki 86836bac55 cpufreq: schedutil: Simplify sugov_fast_switch()
Drop a redundant local variable definition from sugov_fast_switch()
and rearrange the code in there to avoid the redundant logical
negation.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-10-07 17:11:37 +02:00
Christoph Hellwig 849facea92 dma-direct: simplify the DMA_ATTR_NO_KERNEL_MAPPING handling
Use and entirely separate code path for the DMA_ATTR_NO_KERNEL_MAPPING
path.  This avoids any confusion about the ret type, and avoids lots of
attr checks and helpers that can be significantly simplified now.

It also ensures that common handling is applied to architetures still
using the arch alloc/free hooks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-07 11:09:20 +02:00
Christoph Hellwig 5b138c534f dma-direct: factor out a dma_direct_alloc_from_pool helper
This ensures dma_direct_alloc_pages will use the right gfp mask, as
well as keeping the code for that common between the two allocators.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-07 11:07:51 +02:00
Christoph Hellwig 08a89c2830 dma-direct check for highmem pages in dma_direct_alloc_pages
Check for highmem pages from CMA, just like in the dma_direct_alloc path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-07 11:03:21 +02:00
Linus Torvalds 4013c1496c usermodehelper: reset umask to default before executing user process
Kernel threads intentionally do CLONE_FS in order to follow any changes
that 'init' does to set up the root directory (or cwd).

It is admittedly a bit odd, but it avoids the situation where 'init'
does some extensive setup to initialize the system environment, and then
we execute a usermode helper program, and it uses the original FS setup
from boot time that may be very limited and incomplete.

[ Both Al Viro and Eric Biederman point out that 'pivot_root()' will
  follow the root regardless, since it fixes up other users of root (see
  chroot_fs_refs() for details), but overmounting root and doing a
  chroot() would not. ]

However, Vegard Nossum noticed that the CLONE_FS not only means that we
follow the root and current working directories, it also means we share
umask with whatever init changed it to. That wasn't intentional.

Just reset umask to the original default (0022) before actually starting
the usermode helper program.

Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-06 10:31:52 -07:00
Marc Zyngier 04e8c5b2fa Merge branch 'irq/qcom-pdc-wakeup' into irq/irqchip-next
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-10-06 11:28:03 +01:00
Maulik Shah 90428a8eb4 genirq/PM: Introduce IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND flag
An interrupt that is disabled/masked but set for wakeup may still need to
be able to wake up the system from sleep states like "suspend to RAM".

To that effect, introduce the IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND flag.
If the irqchip have this flag set, the irq PM code will enable/unmask
the irqs that are marked for wakeup, but that are in a disabled state.

On resume, such irqs will be restored back to their disabled state.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Maulik Shah <mkshah@codeaurora.org>
[maz: commit message fix-up]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Tested-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/1601267524-20199-4-git-send-email-mkshah@codeaurora.org
2020-10-06 11:23:41 +01:00
Christoph Hellwig 9f4df96b87 dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h>
Move more nitty gritty DMA implementation details into the common
internal header.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:06 +02:00
Christoph Hellwig 19c65c3d30 dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma
Most of the dma_direct symbols should only be used by direct.c and
mapping.c, so move them to kernel/dma.  In fact more of dma-direct.h
should eventually move, but that will require more coordination with
other subsystems.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:06 +02:00
Christoph Hellwig a1fd09e8e6 dma-mapping: move dma-debug.h to kernel/dma/
Most of dma-debug.h is not required by anything outside of kernel/dma.
Move the four declarations needed by dma-mappin.h or dma-ops providers
into dma-mapping.h and dma-map-ops.h, and move the remainder of the
file to kernel/dma/debug.h.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:05 +02:00
Christoph Hellwig 5db5d93089 dma-mapping: remove <asm/dma-contiguous.h>
Just provide a weak default definition of dma_contiguous_early_fixup and
let arm override it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:05 +02:00
Christoph Hellwig 0b1abd1fb7 dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h>
Merge dma-contiguous.h into dma-map-ops.h, after removing the comment
describing the contiguous allocator into kernel/dma/contigous.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:04 +02:00
Christoph Hellwig 580a0cc9c3 dma-contiguous: remove dma_contiguous_set_default
dma_contiguous_set_default contains a trivial assignment, and has a
single caller that is compiled if CONFIG_CMA_DMA is enabled.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:03 +02:00
Christoph Hellwig 5af638931e dma-contiguous: remove dev_set_cma_area
dev_set_cma_area contains a trivial assignment.  It has just three
callers that all have a non-NULL device and depend on CONFIG_DMA_CMA,
so remove the wrapper.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:03 +02:00
Christoph Hellwig 0a0f0d8be7 dma-mapping: split <linux/dma-mapping.h>
Split out all the bits that are purely for dma_map_ops implementations
and related code into a new <linux/dma-map-ops.h> header so that they
don't get pulled into all the drivers.  That also means the architecture
specific <asm/dma-mapping.h> is not pulled in by <linux/dma-mapping.h>
any more, which leads to a missing includes that were pulled in by the
x86 or arm versions in a few not overly portable drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:03 +02:00
Paul Cercueil 0de327969b cma: decrease CMA_ALIGNMENT lower limit to 2
On an embedded system with a tiny (1 MiB) CMA area for video memory, and
a simple enough video pipeline, we can decrease the CMA_ALIGNMENT by a
factor of 2 to avoid wasting memory, as all the allocations for video
buffers will be of the exact same size (dictated by the size of the
screen).

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:06:54 +02:00
David S. Miller 8b0308fe31 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Rejecting non-native endian BTF overlapped with the addition
of support for it.

The rest were more simple overlapping changes, except the
renesas ravb binding update, which had to follow a file
move as well as a YAML conversion.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-05 18:40:01 -07:00
Tom Zanussi bd82631d7c tracing: Add support for dynamic strings to synthetic events
Currently, sythetic events only support static string fields such as:

  # echo 'test_latency u64 lat; char somename[32]' > /sys/kernel/debug/tracing/synthetic_events

Which is fine, but wastes a lot of space in the event.

It also prevents the most commonly-defined strings in the existing
trace events e.g. those defined using __string(), from being passed to
synthetic events via the trace() action.

With this change, synthetic events with dynamic fields can be defined:

  # echo 'test_latency u64 lat; char somename[]' > /sys/kernel/debug/tracing/synthetic_events

And the trace() action can be used to generate events using either
dynamic or static strings:

  # echo 'hist:keys=name:lat=common_timestamp.usecs-$ts0:onmatch(sys.event).test_latency($lat,name)' > /sys/kernel/debug/tracing/events

The synthetic event dynamic strings are implemented in the same way as
the existing __data_loc strings and appear as such in the format file.

[ <rostedt@goodmis.org>: added __set_synth_event_print_fmt() changes:

  I added the following to make it work with trace-cmd. Dynamic strings
  must have __get_str() for events in the print_fmt otherwise it can't be
  parsed correctly. ]

Link: https://lore.kernel.org/r/cover.1601588066.git.zanussi@kernel.org
Link: https://lkml.kernel.org/r/3ed35b6d0e390f5b94cb4a9ba1cc18f5982ab277.1601848695.git.zanussi@kernel.org

Tested-by: Axel Rasmussen <axelrasmussen@google.com>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-05 19:32:18 -04:00
Tom Zanussi 63a1e5de30 tracing: Save normal string variables
String variables created as field variables and save variables are
already handled properly by having their values copied when set.  The
same isn't done for normal variables, but needs to be - simply saving
a pointer to a string contained in an old event isn't sufficient,
since that event's data may quickly become overwritten and therefore a
string pointer to it could yield garbage.

This change uses the same mechanism as field variables and simply
appends the new strings to the existing per-element field_var_str[]
array allocated for that purpose.

Link: https://lkml.kernel.org/r/1c1a03798b02e67307412a0c719d1bfb69b13007.1601848695.git.zanussi@kernel.org

Fixes: 02205a6752 (tracing: Add support for 'field variables')
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-05 18:13:53 -04:00
Tom Zanussi 8fbeb52a59 tracing: Fix parse_synth_field() error handling
synth_field_size() returns either a positive size or an error (zero or
a negative value). However, the existing code assumes the only error
value is 0. It doesn't handle negative error codes, as it assigns
directly to field->size (a size_t; unsigned), thereby interpreting the
error code as a valid size instead.

Do the test before assignment to field->size.

[ axelrasmussen@google.com: changelog addition, first paragraph above ]

Link: https://lkml.kernel.org/r/9b6946d9776b2eeb43227678158196de1c3c6e1d.1601848695.git.zanussi@kernel.org

Fixes: 4b147936fa (tracing: Add support for 'synthetic' events)
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Axel Rasmussen <axelrasmussen@google.com>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-05 18:13:53 -04:00
Tom Zanussi 4a4a56b4e7 tracing: Change STR_VAR_MAX_LEN
32 is too small for this value, and anyway it makes more sense to use
MAX_FILTER_STR_VAL, as this is also the value used for variable-length
__strings.

Link: https://lkml.kernel.org/r/6adfd1668ac1fd8670bd58206944a762061a5559.1601848695.git.zanussi@kernel.org

Tested-by: Axel Rasmussen <axelrasmussen@google.com>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-05 18:13:53 -04:00
Song Liu 39d8f0d102 bpf: Use raw_spin_trylock() for pcpu_freelist_push/pop in NMI
Recent improvements in LOCKDEP highlighted a potential A-A deadlock with
pcpu_freelist in NMI:

./tools/testing/selftests/bpf/test_progs -t stacktrace_build_id_nmi

[   18.984807] ================================
[   18.984807] WARNING: inconsistent lock state
[   18.984808] 5.9.0-rc6-01771-g1466de1330e1 #2967 Not tainted
[   18.984809] --------------------------------
[   18.984809] inconsistent {INITIAL USE} -> {IN-NMI} usage.
[   18.984810] test_progs/1990 [HC2[2]:SC0[0]:HE0:SE1] takes:
[   18.984810] ffffe8ffffc219c0 (&head->lock){....}-{2:2}, at: __pcpu_freelist_pop+0xe3/0x180
[   18.984813] {INITIAL USE} state was registered at:
[   18.984814]   lock_acquire+0x175/0x7c0
[   18.984814]   _raw_spin_lock+0x2c/0x40
[   18.984815]   __pcpu_freelist_pop+0xe3/0x180
[   18.984815]   pcpu_freelist_pop+0x31/0x40
[   18.984816]   htab_map_alloc+0xbbf/0xf40
[   18.984816]   __do_sys_bpf+0x5aa/0x3ed0
[   18.984817]   do_syscall_64+0x2d/0x40
[   18.984818]   entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   18.984818] irq event stamp: 12
[...]
[   18.984822] other info that might help us debug this:
[   18.984823]  Possible unsafe locking scenario:
[   18.984823]
[   18.984824]        CPU0
[   18.984824]        ----
[   18.984824]   lock(&head->lock);
[   18.984826]   <Interrupt>
[   18.984826]     lock(&head->lock);
[   18.984827]
[   18.984828]  *** DEADLOCK ***
[   18.984828]
[   18.984829] 2 locks held by test_progs/1990:
[...]
[   18.984838]  <NMI>
[   18.984838]  dump_stack+0x9a/0xd0
[   18.984839]  lock_acquire+0x5c9/0x7c0
[   18.984839]  ? lock_release+0x6f0/0x6f0
[   18.984840]  ? __pcpu_freelist_pop+0xe3/0x180
[   18.984840]  _raw_spin_lock+0x2c/0x40
[   18.984841]  ? __pcpu_freelist_pop+0xe3/0x180
[   18.984841]  __pcpu_freelist_pop+0xe3/0x180
[   18.984842]  pcpu_freelist_pop+0x17/0x40
[   18.984842]  ? lock_release+0x6f0/0x6f0
[   18.984843]  __bpf_get_stackid+0x534/0xaf0
[   18.984843]  bpf_prog_1fd9e30e1438d3c5_oncpu+0x73/0x350
[   18.984844]  bpf_overflow_handler+0x12f/0x3f0

This is because pcpu_freelist_head.lock is accessed in both NMI and
non-NMI context. Fix this issue by using raw_spin_trylock() in NMI.

Since NMI interrupts non-NMI context, when NMI context tries to lock the
raw_spinlock, non-NMI context of the same CPU may already have locked a
lock and is blocked from unlocking the lock. For a system with N CPUs,
there could be N NMIs at the same time, and they may block N non-NMI
raw_spinlocks. This is tricky for pcpu_freelist_push(), where unlike
_pop(), failing _push() means leaking memory. This issue is more likely to
trigger in non-SMP system.

Fix this issue with an extra list, pcpu_freelist.extralist. The extralist
is primarily used to take _push() when raw_spin_trylock() failed on all
the per CPU lists. It should be empty most of the time. The following
table summarizes the behavior of pcpu_freelist in NMI and non-NMI:

non-NMI pop(): 	use _lock(); check per CPU lists first;
                if all per CPU lists are empty, check extralist;
                if extralist is empty, return NULL.

non-NMI push(): use _lock(); only push to per CPU lists.

NMI pop():    use _trylock(); check per CPU lists first;
              if all per CPU lists are locked or empty, check extralist;
              if extralist is locked or empty, return NULL.

NMI push():   use _trylock(); check per CPU lists first;
              if all per CPU lists are locked; try push to extralist;
              if extralist is also locked, keep trying on per CPU lists.

Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201005165838.3735218-1-songliubraving@fb.com
2020-10-06 00:04:11 +02:00
Linus Torvalds 165563c050 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Make sure SKB control block is in the proper state during IPSEC
    ESP-in-TCP encapsulation. From Sabrina Dubroca.

 2) Various kinds of attributes were not being cloned properly when we
    build new xfrm_state objects from existing ones. Fix from Antony
    Antony.

 3) Make sure to keep BTF sections, from Tony Ambardar.

 4) TX DMA channels need proper locking in lantiq driver, from Hauke
    Mehrtens.

 5) Honour route MTU during forwarding, always. From Maciej
    Żenczykowski.

 6) Fix races in kTLS which can result in crashes, from Rohit
    Maheshwari.

 7) Skip TCP DSACKs with rediculous sequence ranges, from Priyaranjan
    Jha.

 8) Use correct address family in xfrm state lookups, from Herbert Xu.

 9) A bridge FDB flush should not clear out user managed fdb entries
    with the ext_learn flag set, from Nikolay Aleksandrov.

10) Fix nested locking of netdev address lists, from Taehee Yoo.

11) Fix handling of 32-bit DATA_FIN values in mptcp, from Mat Martineau.

12) Fix r8169 data corruptions on RTL8402 chips, from Heiner Kallweit.

13) Don't free command entries in mlx5 while comp handler could still be
    running, from Eran Ben Elisha.

14) Error flow of request_irq() in mlx5 is busted, due to an off by one
    we try to free and IRQ never allocated. From Maor Gottlieb.

15) Fix leak when dumping netlink policies, from Johannes Berg.

16) Sendpage cannot be performed when a page is a slab page, or the page
    count is < 1. Some subsystems such as nvme were doing so. Create a
    "sendpage_ok()" helper and use it as needed, from Coly Li.

17) Don't leak request socket when using syncookes with mptcp, from
    Paolo Abeni.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (111 commits)
  net/core: check length before updating Ethertype in skb_mpls_{push,pop}
  net: mvneta: fix double free of txq->buf
  net_sched: check error pointer in tcf_dump_walker()
  net: team: fix memory leak in __team_options_register
  net: typhoon: Fix a typo Typoon --> Typhoon
  net: hinic: fix DEVLINK build errors
  net: stmmac: Modify configuration method of EEE timers
  tcp: fix syn cookied MPTCP request socket leak
  libceph: use sendpage_ok() in ceph_tcp_sendpage()
  scsi: libiscsi: use sendpage_ok() in iscsi_tcp_segment_map()
  drbd: code cleanup by using sendpage_ok() to check page for kernel_sendpage()
  tcp: use sendpage_ok() to detect misused .sendpage
  nvme-tcp: check page by sendpage_ok() before calling kernel_sendpage()
  net: add WARN_ONCE in kernel_sendpage() for improper zero-copy send
  net: introduce helper sendpage_ok() in include/linux/net.h
  net: usb: pegasus: Proper error handing when setting pegasus' MAC address
  net: core: document two new elements of struct net_device
  netlink: fix policy dump leak
  net/mlx5e: Fix race condition on nhe->n pointer in neigh update
  net/mlx5e: Fix VLAN create flow
  ...
2020-10-05 11:27:14 -07:00
Christoph Hellwig 428805c0c5 PM: hibernate: remove the bogus call to get_gendisk() in software_resume()
get_gendisk grabs a reference on the disk and file operation, so this
code will leak both of them while having absolutely no use for the
gendisk itself.

This effectively reverts commit 2df83fa4bc ("PM / Hibernate: Use
get_gendisk to verify partition if resume_file is integer format")

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-05 18:42:58 +02:00
Christoph Hellwig 10ed16662d block: add a bdget_part helper
All remaining callers of bdget() outside of fs/block_dev.c want to get a
reference to the struct block_device for a given struct hd_struct.  Add
a helper just for that and then mark bdget static.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-05 10:38:33 -06:00
Gustavo A. R. Silva 4e797e6ec7 printk: Use fallthrough pseudo-keyword
Replace /* FALL THRU */ comment with the new pseudo-keyword macro
fallthrough[1].

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20201002224627.GA30475@embeddedor
2020-10-05 15:56:58 +02:00
Gustavo A. R. Silva 8731745e48 bpf, verifier: Use fallthrough pseudo-keyword
Replace /* fallthrough */ comments with the new pseudo-keyword
macro fallthrough [1].

  [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20201002234217.GA12280@embeddedor
2020-10-05 15:52:36 +02:00
Viresh Kumar 08d8c65e84 cpufreq: Move traces and update to policy->cur to cpufreq core
The cpufreq core handles the updates to policy->cur and recording of
cpufreq trace events for all the governors except schedutil's fast
switch case.

Move that as well to cpufreq core for consistency and readability.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-05 15:13:43 +02:00
Kees Cook 0fa8e08464 fs/kernel_file_read: Add "offset" arg for partial reads
To perform partial reads, callers of kernel_read_file*() must have a
non-NULL file_size argument and a preallocated buffer. The new "offset"
argument can then be used to seek to specific locations in the file to
fill the buffer to, at most, "buf_size" per call.

Where possible, the LSM hooks can report whether a full file has been
read or not so that the contents can be reasoned about.

Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20201002173828.2099543-14-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:04 +02:00
Kees Cook 38f901735a module: Call security_kernel_post_load_data()
Now that there is an API for checking loaded contents for modules
loaded without a file, call into the LSM hooks.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: KP Singh <kpsingh@google.com>
Acked-by: Jessica Yu <jeyu@kernel.org>
Link: https://lore.kernel.org/r/20201002173828.2099543-11-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:03 +02:00
Kees Cook b64fcae74b LSM: Introduce kernel_post_load_data() hook
There are a few places in the kernel where LSMs would like to have
visibility into the contents of a kernel buffer that has been loaded or
read. While security_kernel_post_read_file() (which includes the
buffer) exists as a pairing for security_kernel_read_file(), no such
hook exists to pair with security_kernel_load_data().

Earlier proposals for just using security_kernel_post_read_file() with a
NULL file argument were rejected (i.e. "file" should always be valid for
the security_..._file hooks, but it appears at least one case was
left in the kernel during earlier refactoring. (This will be fixed in
a subsequent patch.)

Since not all cases of security_kernel_load_data() can have a single
contiguous buffer made available to the LSM hook (e.g. kexec image
segments are separately loaded), there needs to be a way for the LSM to
reason about its expectations of the hook coverage. In order to handle
this, add a "contents" argument to the "kernel_load_data" hook that
indicates if the newly added "kernel_post_load_data" hook will be called
with the full contents once loaded. That way, LSMs requiring full contents
can choose to unilaterally reject "kernel_load_data" with contents=false
(which is effectively the existing hook coverage), but when contents=true
they can allow it and later evaluate the "kernel_post_load_data" hook
once the buffer is loaded.

With this change, LSMs can gain coverage over non-file-backed data loads
(e.g. init_module(2) and firmware userspace helper), which will happen
in subsequent patches.

Additionally prepare IMA to start processing these cases.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: KP Singh <kpsingh@google.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-9-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:03 +02:00
Kees Cook 885352881f fs/kernel_read_file: Add file_size output argument
In preparation for adding partial read support, add an optional output
argument to kernel_read_file*() that reports the file size so callers
can reason more easily about their reading progress.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-8-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:03 +02:00
Kees Cook f7a4f689bc fs/kernel_read_file: Remove redundant size argument
In preparation for refactoring kernel_read_file*(), remove the redundant
"size" argument which is not needed: it can be included in the return
code, with callers adjusted. (VFS reads already cannot be larger than
INT_MAX.)

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-6-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:18 +02:00
Scott Branden b89999d004 fs/kernel_read_file: Split into separate include file
Move kernel_read_file* out of linux/fs.h to its own linux/kernel_read_file.h
include file. That header gets pulled in just about everywhere
and doesn't really need functions not related to the general fs interface.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/r/20200706232309.12010-2-scott.branden@broadcom.com
Link: https://lore.kernel.org/r/20201002173828.2099543-4-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:18 +02:00
Kees Cook c307459b9d fs/kernel_read_file: Remove FIRMWARE_PREALLOC_BUFFER enum
FIRMWARE_PREALLOC_BUFFER is a "how", not a "what", and confuses the LSMs
that are interested in filtering between types of things. The "how"
should be an internal detail made uninteresting to the LSMs.

Fixes: a098ecd2fa ("firmware: support loading into a pre-allocated buffer")
Fixes: fd90bc559b ("ima: based on policy verify firmware signatures (pre-allocated buffer)")
Fixes: 4f0496d8ff ("ima: based on policy warn about loading firmware (pre-allocated buffer)")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201002173828.2099543-2-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:18 +02:00
Tingwei Zhang 458999c6f6 tracing: Add trace_export support for trace_marker
Add the support to route trace_marker buffer to other destination
via trace_export.

Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lore.kernel.org/r/20201005071319.78508-5-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 12:43:53 +02:00
Tingwei Zhang 8ab7a2b705 tracing: Add trace_export support for event trace
Only function traces can be exported to other destinations currently.
This patch exports event trace as well. Move trace export related
function to the beginning of file so other trace can call
trace_process_export() to export.

Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lore.kernel.org/r/20201005071319.78508-4-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 12:43:53 +02:00
Tingwei Zhang 8438f52114 tracing: Add flag to control different traces
More traces like event trace or trace marker will be supported.
Add flag for difference traces, so that they can be controlled
separately. Move current function trace to it's own flag
instead of global ftrace enable flag.

Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lore.kernel.org/r/20201005071319.78508-3-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 12:43:53 +02:00
Daniel Bristot de Oliveira feff2e65ef sched/deadline: Unthrottle PI boosted threads while enqueuing
stress-ng has a test (stress-ng --cyclic) that creates a set of threads
under SCHED_DEADLINE with the following parameters:

    dl_runtime   =  10000 (10 us)
    dl_deadline  = 100000 (100 us)
    dl_period    = 100000 (100 us)

These parameters are very aggressive. When using a system without HRTICK
set, these threads can easily execute longer than the dl_runtime because
the throttling happens with 1/HZ resolution.

During the main part of the test, the system works just fine because
the workload does not try to run over the 10 us. The problem happens at
the end of the test, on the exit() path. During exit(), the threads need
to do some cleanups that require real-time mutex locks, mainly those
related to memory management, resulting in this scenario:

Note: locks are rt_mutexes...
 ------------------------------------------------------------------------
    TASK A:		TASK B:				TASK C:
    activation
							activation
			activation

    lock(a): OK!	lock(b): OK!
    			<overrun runtime>
    			lock(a)
    			-> block (task A owns it)
			  -> self notice/set throttled
 +--<			  -> arm replenished timer
 |    			switch-out
 |    							lock(b)
 |    							-> <C prio > B prio>
 |    							-> boost TASK B
 |  unlock(a)						switch-out
 |  -> handle lock a to B
 |    -> wakeup(B)
 |      -> B is throttled:
 |        -> do not enqueue
 |     switch-out
 |
 |
 +---------------------> replenishment timer
			-> TASK B is boosted:
			  -> do not enqueue
 ------------------------------------------------------------------------

BOOM: TASK B is runnable but !enqueued, holding TASK C: the system
crashes with hung task C.

This problem is avoided by removing the throttle state from the boosted
thread while boosting it (by TASK A in the example above), allowing it to
be queued and run boosted.

The next replenishment will take care of the runtime overrun, pushing
the deadline further away. See the "while (dl_se->runtime <= 0)" on
replenish_dl_entity() for more information.

Reported-by: Mark Simmons <msimmons@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Juri Lelli <juri.lelli@redhat.com>
Tested-by: Mark Simmons <msimmons@redhat.com>
Link: https://lkml.kernel.org/r/5076e003450835ec74e6fa5917d02c4fa41687e6.1600170294.git.bristot@redhat.com
2020-10-03 16:30:53 +02:00
Vincent Donnefort 51cf18c90c sched/debug: Add new tracepoint to track cpu_capacity
rq->cpu_capacity is a key element in several scheduler parts, such as EAS
task placement and load balancing. Tracking this value enables testing
and/or debugging by a toolkit.

Signed-off-by: Vincent Donnefort <vincent.donnefort@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1598605249-72651-1-git-send-email-vincent.donnefort@arm.com
2020-10-03 16:30:52 +02:00
Peter Oskolkov 9abb897345 sched/fair: Tweak pick_next_entity()
Currently, pick_next_entity(...) has the following structure
(simplified):

  [...]
  if (last_buddy_ok())
    result = last_buddy;
  if (next_buddy_ok())
    result = next_buddy;
  [...]

The intended behavior is to prefer next buddy over last buddy;
the current code somewhat obfuscates this, and also wastes
cycles checking the last buddy when eventually the next buddy is
picked up.

So this patch refactors two 'ifs' above into

  [...]
  if (next_buddy_ok())
      result = next_buddy;
  else if (last_buddy_ok())
      result = last_buddy;
  [...]

Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guitttot@linaro.org>
Link: https://lkml.kernel.org/r/20200930173532.1069092-1-posk@google.com
2020-10-03 16:30:52 +02:00
Stanislav Fomichev 1028ae4069 bpf: Deref map in BPF_PROG_BIND_MAP when it's already used
We are missing a deref for the case when we are doing BPF_PROG_BIND_MAP
on a map that's being already held by the program.
There is 'if (ret) bpf_map_put(map)' below which doesn't trigger
because we don't consider this an error.
Let's add missing bpf_map_put() for this specific condition.

Fixes: ef15314aa5 ("bpf: Add BPF_PROG_BIND_MAP syscall")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20201003002544.3601440-1-sdf@google.com
2020-10-02 19:21:25 -07:00
Jakub Kicinski 7c1e0926da taskstats: move specifying netlink policy back to ops
commit 3b0f31f2b8 ("genetlink: make policy common to family")
had to work around removal of policy from ops by parsing in
the pre_doit callback. Now that policy is back in full ops
we can switch again. Set maxattr to actual size of the policies
- both commands set GENL_DONT_VALIDATE_STRICT so out of range
attributes will be silently ignored, anyway.

v2:
 - remove stale comment

Suggested-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 19:11:12 -07:00
Jakub Kicinski 66a9b9287d genetlink: move to smaller ops wherever possible
Bulk of the genetlink users can use smaller ops, move them.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 19:11:11 -07:00
Hao Luo 63d9b80dcf bpf: Introducte bpf_this_cpu_ptr()
Add bpf_this_cpu_ptr() to help access percpu var on this cpu. This
helper always returns a valid pointer, therefore no need to check
returned value for NULL. Also note that all programs run with
preemption disabled, which means that the returned pointer is stable
during all the execution of the program.

Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200929235049.2533242-6-haoluo@google.com
2020-10-02 15:00:49 -07:00
Hao Luo eaa6bcb71e bpf: Introduce bpf_per_cpu_ptr()
Add bpf_per_cpu_ptr() to help bpf programs access percpu vars.
bpf_per_cpu_ptr() has the same semantic as per_cpu_ptr() in the kernel
except that it may return NULL. This happens when the cpu parameter is
out of range. So the caller must check the returned value.

Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200929235049.2533242-5-haoluo@google.com
2020-10-02 15:00:49 -07:00
Hao Luo 4976b718c3 bpf: Introduce pseudo_btf_id
Pseudo_btf_id is a type of ld_imm insn that associates a btf_id to a
ksym so that further dereferences on the ksym can use the BTF info
to validate accesses. Internally, when seeing a pseudo_btf_id ld insn,
the verifier reads the btf_id stored in the insn[0]'s imm field and
marks the dst_reg as PTR_TO_BTF_ID. The btf_id points to a VAR_KIND,
which is encoded in btf_vminux by pahole. If the VAR is not of a struct
type, the dst reg will be marked as PTR_TO_MEM instead of PTR_TO_BTF_ID
and the mem_size is resolved to the size of the VAR's type.

>From the VAR btf_id, the verifier can also read the address of the
ksym's corresponding kernel var from kallsyms and use that to fill
dst_reg.

Therefore, the proper functionality of pseudo_btf_id depends on (1)
kallsyms and (2) the encoding of kernel global VARs in pahole, which
should be available since pahole v1.18.

Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200929235049.2533242-2-haoluo@google.com
2020-10-02 14:59:25 -07:00
Nathan Chancellor 69e0ad37c9 static_call: Fix return type of static_call_init
Functions that are passed to early_initcall should be of type
initcall_t, which expects a return type of int. This is not currently an
error but a patch in the Clang LTO series could change that in the
future.

Fixes: 9183c3f9ed ("static_call: Add inline static call infrastructure")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/lkml/20200903203053.3411268-17-samitolvanen@google.com/
2020-10-02 21:18:25 +02:00
Steven Rostedt (VMware) 547305a646 tracepoint: Fix out of sync data passing by static caller
Naresh reported a bug that appears to be a side effect of the static
calls. It happens when going from more than one tracepoint callback to
a single one, and removing the first callback on the list. The list of
tracepoint callbacks holds data and a function to call with the
parameters of that tracepoint and a handler to the associated data.

 old_list:
	0: func = foo; data = NULL;
	1: func = bar; data = &bar_struct;

 new_list:
	0: func = bar; data = &bar_struct;

	CPU 0				CPU 1
	-----				-----
   tp_funcs = old_list;
   tp_static_caller = tp_interator

   __DO_TRACE()

    data = tp_funcs[0].data = NULL;

				   tp_funcs = new_list;
				   tracepoint_update_call()
				      tp_static_caller = tp_funcs[0] = bar;
    tp_static_caller(data)
       bar(data)
         x = data->item = NULL->item

       BOOM!

To solve this, add a tracepoint_synchronize_unregister() between
changing tp_funcs and updating the static tracepoint, that does both a
synchronize_rcu() and synchronize_srcu(). This will ensure that when
the static call is updated to the single callback that it will be
receiving the data that it registered with.

Fixes: d25e37d89d ("tracepoint: Optimize using static_call()")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/linux-next/CA+G9fYvPXVRO0NV7yL=FxCmFEMYkCwdz7R=9W+_votpT824YJA@mail.gmail.com
2020-10-02 21:18:25 +02:00
Qiujun Huang fdda88d31a ftrace: Fix some typos in comment
s/coorditate/coordinate/
s/emty/empty/
s/preeptive/preemptive/
s/succes/success/
s/carefule/careful/

Link: https://lkml.kernel.org/r/20201002143126.2890-1-hqjagain@gmail.com

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-02 14:05:48 -04:00
Linus Torvalds aa5ff93523 Two tracing fixes:
- Fix temp buffer accounting that caused a WARNING for
   ftrace_dump_on_opps()
 
 - Move the recursion check in one of the function callback helpers to the
   beginning of the function, as if the rcu_is_watching() gets traced, it
   will cause a recursive loop that will crash the kernel.
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCX3UZ7hQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qlelAP4nzEIyE7s8HkKHo+IEvzEiYL523Xq7
 zrTm27XnLjZ+EQD9ECbtea9me8kL+zBcG8H3Wu/ykN15LIT2ZsvVTrWYmwI=
 =eTh4
 -----END PGP SIGNATURE-----

Merge tag 'trace-v5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Two tracing fixes:

   - Fix temp buffer accounting that caused a WARNING for
     ftrace_dump_on_opps()

   - Move the recursion check in one of the function callback helpers to
     the beginning of the function, as if the rcu_is_watching() gets
     traced, it will cause a recursive loop that will crash the kernel"

* tag 'trace-v5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Move RCU is watching check after recursion check
  tracing: Fix trace_find_next_entry() accounting of temp buffer size
2020-10-01 09:41:02 -07:00
Daniel Thompson d081a6e353 kdb: Fix pager search for multi-line strings
Currently using forward search doesn't handle multi-line strings correctly.
The search routine replaces line breaks with \0 during the search and, for
regular searches ("help | grep Common\n"), there is code after the line
has been discarded or printed to replace the break character.

However during a pager search ("help\n" followed by "/Common\n") when the
string is matched we will immediately return to normal output and the code
that should restore the \n becomes unreachable. Fix this by restoring the
replaced character when we disable the search mode and update the comment
accordingly.

Fixes: fb6daa7520 ("kdb: Provide forward search at more prompt")
Link: https://lore.kernel.org/r/20200909141708.338273-1-daniel.thompson@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-10-01 14:44:08 +01:00
Daniel Thompson 771910f719 kernel: debug: Centralize dbg_[de]activate_sw_breakpoints
During debug trap execution we expect dbg_deactivate_sw_breakpoints()
to be paired with an dbg_activate_sw_breakpoint(). Currently although
the calls are paired correctly they are needlessly smeared across three
different functions. Worse this also results in code to drive polled I/O
being called with breakpoints activated which, in turn, needlessly
increases the set of functions that will recursively trap if breakpointed.

Fix this by moving the activation of breakpoints into the debug core.

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200927211531.1380577-4-daniel.thompson@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-10-01 14:23:45 +01:00
Daniel Thompson 4c4197eda7 kgdb: Add NOKPROBE labels on the trap handler functions
Currently kgdb honours the kprobe blocklist but doesn't place its own
trap handling code on the list. Add labels to discourage attempting to
use kgdb to debug itself.

Not every functions that executes from the trap handler needs to be
marked up: relatively early in the trap handler execution (just after
we bring the other CPUs to a halt) all breakpoints are replaced with
the original opcodes. This patch marks up code in the debug_core that
executes between trap entry and the breakpoints being deactivated
and, also, code that executes between breakpoint activation and trap
exit.

To be clear these changes are not sufficient to make recursive trapping
impossible since they do not include library calls made during kgdb's
entry/exit logic. However going much further whilst we are sharing the
kprobe blocklist risks reducing the capabilities of kprobe and this
would be a bad trade off (especially so given kgdb's users are currently
conditioned to avoid recursive traps).

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200927211531.1380577-3-daniel.thompson@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-10-01 14:23:21 +01:00
Song Liu 792caccc45 bpf: Introduce BPF_F_PRESERVE_ELEMS for perf event array
Currently, perf event in perf event array is removed from the array when
the map fd used to add the event is closed. This behavior makes it
difficult to the share perf events with perf event array.

Introduce perf event map that keeps the perf event open with a new flag
BPF_F_PRESERVE_ELEMS. With this flag set, perf events in the array are not
removed when the original map fd is closed. Instead, the perf event will
stay in the map until 1) it is explicitly removed from the array; or 2)
the array is freed.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200930224927.1936644-2-songliubraving@fb.com
2020-09-30 23:18:12 -07:00
Jens Axboe 0f2122045b io_uring: don't rely on weak ->files references
Grab actual references to the files_struct. To avoid circular references
issues due to this, we add a per-task note that keeps track of what
io_uring contexts a task has used. When the tasks execs or exits its
assigned files, we cancel requests based on this tracking.

With that, we can grab proper references to the files table, and no
longer need to rely on stashing away ring_fd and ring_file to check
if the ring_fd may have been closed.

Cc: stable@vger.kernel.org # v5.5+
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-30 20:32:32 -06:00
Daniel Borkmann 92acdc58ab bpf, net: Rework cookie generator as per-cpu one
With its use in BPF, the cookie generator can be called very frequently
in particular when used out of cgroup v2 hooks (e.g. connect / sendmsg)
and attached to the root cgroup, for example, when used in v1/v2 mixed
environments. In particular, when there's a high churn on sockets in the
system there can be many parallel requests to the bpf_get_socket_cookie()
and bpf_get_netns_cookie() helpers which then cause contention on the
atomic counter.

As similarly done in f991bd2e14 ("fs: introduce a per-cpu last_ino
allocator"), add a small helper library that both can use for the 64 bit
counters. Given this can be called from different contexts, we also need
to deal with potential nested calls even though in practice they are
considered extremely rare. One idea as suggested by Eric Dumazet was
to use a reverse counter for this situation since we don't expect 64 bit
overflows anyways; that way, we can avoid bigger gaps in the 64 bit
counter space compared to just batch-wise increase. Even on machines
with small number of cores (e.g. 4) the cookie generation shrinks from
min/max/med/avg (ns) of 22/50/40/38.9 down to 10/35/14/17.3 when run
in parallel from multiple CPUs.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Link: https://lore.kernel.org/bpf/8a80b8d27d3c49f9a14e1d5213c19d8be87d1dc8.1601477936.git.daniel@iogearbox.net
2020-09-30 11:50:35 -07:00
Jouni Roivas 65026da59c cgroup: Zero sized write should be no-op
Do not report failure on zero sized writes, and handle them as no-op.

There's issues for example in case of writev() when there's iovec
containing zero buffer as a first one. It's expected writev() on below
example to successfully perform the write to specified writable cgroup
file expecting integer value, and to return 2. For now it's returning
value -1, and skipping the write:

	int writetest(int fd) {
	  const char *buf1 = "";
	  const char *buf2 = "1\n";
          struct iovec iov[2] = {
                { .iov_base = (void*)buf1, .iov_len = 0 },
                { .iov_base = (void*)buf2, .iov_len = 2 }
          };
	  return writev(fd, iov, 2);
	}

This patch fixes the issue by checking if there's nothing to write,
and handling the write as no-op by just returning 0.

Signed-off-by: Jouni Roivas <jouni.roivas@tuxera.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2020-09-30 13:52:06 -04:00
Wei Yang 95d325185c cgroup: remove redundant kernfs_activate in cgroup_setup_root()
This step is already done in rebind_subsystems().

Not necessary to do it again.

Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2020-09-30 12:03:10 -04:00
John Ogness 0463d04ea0 printk: reduce setup_text_buf size to LOG_LINE_MAX
@setup_text_buf only copies the original text messages (without any
prefix or extended text). It only needs to be LOG_LINE_MAX in size.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200930090134.8723-3-john.ogness@linutronix.de
2020-09-30 13:54:21 +02:00
John Ogness 59f8bcca1e printk: avoid and/or handle record truncation
If a reader provides a buffer that is smaller than the message text,
the @text_len field of @info will have a value larger than the buffer
size. If readers blindly read @text_len bytes of data without
checking the size, they will read beyond their buffer.

Add this check to record_print_text() to properly recognize when such
truncation has occurred.

Add a maximum size argument to the ringbuffer function to extend
records so that records can not be created that are larger than the
buffer size of readers.

When extending records (LOG_CONT), do not extend records beyond
LOG_LINE_MAX since that is the maximum size available in the buffers
used by consoles and syslog.

Fixes: f5f022e53b ("printk: reimplement log_cont using record extension")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200930090134.8723-2-john.ogness@linutronix.de
2020-09-30 13:30:28 +02:00
David S. Miller 1f25c9bbfd Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Alexei Starovoitov says:

====================
pull-request: bpf 2020-09-29

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

We've added 7 non-merge commits during the last 14 day(s) which contain
a total of 7 files changed, 28 insertions(+), 8 deletions(-).

The main changes are:

1) fix xdp loading regression in libbpf for old kernels, from Andrii.

2) Do not discard packet when NETDEV_TX_BUSY, from Magnus.

3) Fix corner cases in libbpf related to endianness and kconfig, from Tony.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-30 01:49:20 -07:00
Toke Høiland-Jørgensen 43bc2874e7 bpf: Fix context type resolving for extension programs
Eelco reported we can't properly access arguments if the tracing
program is attached to extension program.

Having following program:

  SEC("classifier/test_pkt_md_access")
  int test_pkt_md_access(struct __sk_buff *skb)

with its extension:

  SEC("freplace/test_pkt_md_access")
  int test_pkt_md_access_new(struct __sk_buff *skb)

and tracing that extension with:

  SEC("fentry/test_pkt_md_access_new")
  int BPF_PROG(fentry, struct sk_buff *skb)

It's not possible to access skb argument in the fentry program,
with following error from verifier:

  ; int BPF_PROG(fentry, struct sk_buff *skb)
  0: (79) r1 = *(u64 *)(r1 +0)
  invalid bpf_context access off=0 size=8

The problem is that btf_ctx_access gets the context type for the
traced program, which is in this case the extension.

But when we trace extension program, we want to get the context
type of the program that the extension is attached to, so we can
access the argument properly in the trace program.

This version of the patch is tweaked slightly from Jiri's original one,
since the refactoring in the previous patches means we have to get the
target prog type from the new variable in prog->aux instead of directly
from the target prog.

Reported-by: Eelco Chaudron <echaudro@redhat.com>
Suggested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/160138355278.48470.17057040257274725638.stgit@toke.dk
2020-09-29 13:09:24 -07:00
Toke Høiland-Jørgensen 4a1e7c0c63 bpf: Support attaching freplace programs to multiple attach points
This enables support for attaching freplace programs to multiple attach
points. It does this by amending the UAPI for bpf_link_Create with a target
btf ID that can be used to supply the new attachment point along with the
target program fd. The target must be compatible with the target that was
supplied at program load time.

The implementation reuses the checks that were factored out of
check_attach_btf_id() to ensure compatibility between the BTF types of the
old and new attachment. If these match, a new bpf_tracing_link will be
created for the new attach target, allowing multiple attachments to
co-exist simultaneously.

The code could theoretically support multiple-attach of other types of
tracing programs as well, but since I don't have a use case for any of
those, there is no API support for doing so.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/160138355169.48470.17165680973640685368.stgit@toke.dk
2020-09-29 13:09:24 -07:00
Toke Høiland-Jørgensen 3aac1ead5e bpf: Move prog->aux->linked_prog and trampoline into bpf_link on attach
In preparation for allowing multiple attachments of freplace programs, move
the references to the target program and trampoline into the
bpf_tracing_link structure when that is created. To do this atomically,
introduce a new mutex in prog->aux to protect writing to the two pointers
to target prog and trampoline, and rename the members to make it clear that
they are related.

With this change, it is no longer possible to attach the same tracing
program multiple times (detaching in-between), since the reference from the
tracing program to the target disappears on the first attach. However,
since the next patch will let the caller supply an attach target, that will
also make it possible to attach to the same place multiple times.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/160138355059.48470.2503076992210324984.stgit@toke.dk
2020-09-29 13:09:23 -07:00
Toke Høiland-Jørgensen 9d9aae53b9 bpf/preload: Make sure Makefile cleans up after itself, and add .gitignore
The Makefile in bpf/preload builds a local copy of libbpf, but does not
properly clean up after itself. This can lead to subsequent compilation
failures, since the feature detection cache is kept around which can lead
subsequent detection to fail.

Fix this by properly setting clean-files, and while we're at it, also add a
.gitignore for the directory to ignore the build artifacts.

Fixes: d71fa5c976 ("bpf: Add kernel module with user mode driver that populates bpffs.")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200927193005.8459-1-toke@redhat.com
2020-09-29 11:15:01 -07:00
Steven Rostedt (VMware) b40341fad6 ftrace: Move RCU is watching check after recursion check
The first thing that the ftrace function callback helper functions should do
is to check for recursion. Peter Zijlstra found that when
"rcu_is_watching()" had its notrace removed, it caused perf function tracing
to crash. This is because the call of rcu_is_watching() is tested before
function recursion is checked and and if it is traced, it will cause an
infinite recursion loop.

rcu_is_watching() should still stay notrace, but to prevent this should
never had crashed in the first place. The recursion prevention must be the
first thing done in callback functions.

Link: https://lore.kernel.org/r/20200929112541.GM2628@hirez.programming.kicks-ass.net

Cc: stable@vger.kernel.org
Cc: Paul McKenney <paulmck@kernel.org>
Fixes: c68c0fa293 ("ftrace: Have ftrace_ops_get_func() handle RCU and PER_CPU flags too")
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-29 13:05:10 -04:00
Steven Rostedt (VMware) 851e6f61cd tracing: Fix trace_find_next_entry() accounting of temp buffer size
The temp buffer size variable for trace_find_next_entry() was incorrectly
being updated when the size did not change. The temp buffer size should only
be updated when it is reallocated.

This is mostly an issue when used with ftrace_dump(). That's because
ftrace_dump() can not allocate a new buffer, and instead uses a temporary
buffer with a fix size. But the variable that keeps track of that size is
incorrectly updated with each call, and it could fall into the path that
would try to reallocate the buffer and produce a warning.

 ------------[ cut here ]------------
 WARNING: CPU: 1 PID: 1601 at kernel/trace/trace.c:3548
trace_find_next_entry+0xd0/0xe0
 Modules linked in [..]
 CPU: 1 PID: 1601 Comm: bash Not tainted 5.9.0-rc5-test+ #521
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03
07/14/2016
 RIP: 0010:trace_find_next_entry+0xd0/0xe0
 Code: 40 21 00 00 4c 89 e1 31 d2 4c 89 ee 48 89 df e8 c6 9e ff ff 89 ab 54
21 00 00 5b 5d 41 5c 41 5d c3 48 63 d5 eb bf 31 c0 eb f0 <0f> 0b 48 63 d5 eb
b4 66 0f 1f 84 00 00 00 00 00 53 48 8d 8f 60 21
 RSP: 0018:ffff95a4f2e8bd70 EFLAGS: 00010046
 RAX: ffffffff96679fc0 RBX: ffffffff97910de0 RCX: ffffffff96679fc0
 RDX: ffff95a4f2e8bd98 RSI: ffff95a4ee321098 RDI: ffffffff97913000
 RBP: 0000000000000018 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000001 R11: 0000000000000046 R12: ffff95a4f2e8bd98
 R13: 0000000000000000 R14: ffff95a4ee321098 R15: 00000000009aa301
 FS:  00007f8565484740(0000) GS:ffff95a55aa40000(0000)
knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000055876bd43d90 CR3: 00000000b76e6003 CR4: 00000000001706e0
 Call Trace:
  trace_print_lat_context+0x58/0x2d0
  ? cpumask_next+0x16/0x20
  print_trace_line+0x1a4/0x4f0
  ftrace_dump.cold+0xad/0x12c
  __handle_sysrq.cold+0x51/0x126
  write_sysrq_trigger+0x3f/0x4a
  proc_reg_write+0x53/0x80
  vfs_write+0xca/0x210
  ksys_write+0x70/0xf0
  do_syscall_64+0x33/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xa9
 RIP: 0033:0x7f8565579487
 Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa
64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff
77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
 RSP: 002b:00007ffd40707948 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f8565579487
 RDX: 0000000000000002 RSI: 000055876bd74de0 RDI: 0000000000000001
 RBP: 000055876bd74de0 R08: 000000000000000a R09: 0000000000000001
 R10: 000055876bdec280 R11: 0000000000000246 R12: 0000000000000002
 R13: 00007f856564a500 R14: 0000000000000002 R15: 00007f856564a700
 irq event stamp: 109958
 ---[ end trace 7aab5b7e51484b00 ]---

Not only fix the updating of the temp buffer, but also do not free the temp
buffer before a new buffer is allocated (there's no reason to not continue
to use the current temp buffer if an allocation fails).

Cc: stable@vger.kernel.org
Fixes: 8e99cf91b9 ("tracing: Do not allocate buffer in trace_find_next_entry() in atomic")
Reported-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-29 12:46:22 -04:00
Boqun Feng 6d1823ccc4 lockdep: Optimize the memory usage of circular queue
Qian Cai reported a BFS_EQUEUEFULL warning [1] after read recursive
deadlock detection merged into tip tree recently. Unlike the previous
lockep graph searching, which iterate every lock class (every node in
the graph) exactly once, the graph searching for read recurisve deadlock
detection needs to iterate every lock dependency (every edge in the
graph) once, as a result, the maximum memory cost of the circular queue
changes from O(V), where V is the number of lock classes (nodes or
vertices) in the graph, to O(E), where E is the number of lock
dependencies (edges), because every lock class or dependency gets
enqueued once in the BFS. Therefore we hit the BFS_EQUEUEFULL case.

However, actually we don't need to enqueue all dependencies for the BFS,
because every time we enqueue a dependency, we almostly enqueue all
other dependencies in the same dependency list ("almostly" is because
we currently check before enqueue, so if a dependency doesn't pass the
check stage we won't enqueue it, however, we can always do in reverse
ordering), based on this, we can only enqueue the first dependency from
a dependency list and every time we want to fetch a new dependency to
work, we can either:

  1)	fetch the dependency next to the current dependency in the
	dependency list
or

  2)	if the dependency in 1) doesn't exist, fetch the dependency from
	the queue.

With this approach, the "max bfs queue depth" for a x86_64_defconfig +
lockdep and selftest config kernel can get descreased from:

        max bfs queue depth:                   201

to (after apply this patch)

        max bfs queue depth:                   61

While I'm at it, clean up the code logic a little (e.g. directly return
other than set a "ret" value and goto the "exit" label).

[1]: https://lore.kernel.org/lkml/17343f6f7f2438fc376125384133c5ba70c2a681.camel@redhat.com/

Reported-by: Qian Cai <cai@redhat.com>
Reported-by: syzbot+62ebe501c1ce9a91f68c@syzkaller.appspotmail.com
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200917080210.108095-1-boqun.feng@gmail.com
2020-09-29 09:56:59 +02:00
Alan Maguire eb411377ae bpf: Add bpf_seq_printf_btf helper
A helper is added to allow seq file writing of kernel data
structures using vmlinux BTF.  Its signature is

long bpf_seq_printf_btf(struct seq_file *m, struct btf_ptr *ptr,
                        u32 btf_ptr_size, u64 flags);

Flags and struct btf_ptr definitions/use are identical to the
bpf_snprintf_btf helper, and the helper returns 0 on success
or a negative error value.

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-8-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Alan Maguire af65320948 bpf: Bump iter seq size to support BTF representation of large data structures
BPF iter size is limited to PAGE_SIZE; if we wish to display BTF-based
representations of larger kernel data structures such as task_struct,
this will be insufficient.

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-6-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Alan Maguire c4d0bfb450 bpf: Add bpf_snprintf_btf helper
A helper is added to support tracing kernel type information in BPF
using the BPF Type Format (BTF).  Its signature is

long bpf_snprintf_btf(char *str, u32 str_size, struct btf_ptr *ptr,
		      u32 btf_ptr_size, u64 flags);

struct btf_ptr * specifies

- a pointer to the data to be traced
- the BTF id of the type of data pointed to
- a flags field is provided for future use; these flags
  are not to be confused with the BTF_F_* flags
  below that control how the btf_ptr is displayed; the
  flags member of the struct btf_ptr may be used to
  disambiguate types in kernel versus module BTF, etc;
  the main distinction is the flags relate to the type
  and information needed in identifying it; not how it
  is displayed.

For example a BPF program with a struct sk_buff *skb
could do the following:

	static struct btf_ptr b = { };

	b.ptr = skb;
	b.type_id = __builtin_btf_type_id(struct sk_buff, 1);
	bpf_snprintf_btf(str, sizeof(str), &b, sizeof(b), 0, 0);

Default output looks like this:

(struct sk_buff){
 .transport_header = (__u16)65535,
 .mac_header = (__u16)65535,
 .end = (sk_buff_data_t)192,
 .head = (unsigned char *)0x000000007524fd8b,
 .data = (unsigned char *)0x000000007524fd8b,
 .truesize = (unsigned int)768,
 .users = (refcount_t){
  .refs = (atomic_t){
   .counter = (int)1,
  },
 },
}

Flags modifying display are as follows:

- BTF_F_COMPACT:	no formatting around type information
- BTF_F_NONAME:		no struct/union member names/types
- BTF_F_PTR_RAW:	show raw (unobfuscated) pointer values;
			equivalent to %px.
- BTF_F_ZERO:		show zero-valued struct/union members;
			they are not displayed by default

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-4-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Alan Maguire 31d0bc8163 bpf: Move to generic BTF show support, apply it to seq files/strings
generalize the "seq_show" seq file support in btf.c to support
a generic show callback of which we support two instances; the
current seq file show, and a show with snprintf() behaviour which
instead writes the type data to a supplied string.

Both classes of show function call btf_type_show() with different
targets; the seq file or the string to be written.  In the string
case we need to track additional data - length left in string to write
and length to return that we would have written (a la snprintf).

By default show will display type information, field members and
their types and values etc, and the information is indented
based upon structure depth. Zeroed fields are omitted.

Show however supports flags which modify its behaviour:

BTF_SHOW_COMPACT - suppress newline/indent.
BTF_SHOW_NONAME - suppress show of type and member names.
BTF_SHOW_PTR_RAW - do not obfuscate pointer values.
BTF_SHOW_UNSAFE - do not copy data to safe buffer before display.
BTF_SHOW_ZERO - show zeroed values (by default they are not shown).

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-3-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Alan Maguire 76654e67f3 bpf: Provide function to get vmlinux BTF information
It will be used later for BPF structure display support

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-2-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Toke Høiland-Jørgensen f7b12b6fea bpf: verifier: refactor check_attach_btf_id()
The check_attach_btf_id() function really does three things:

1. It performs a bunch of checks on the program to ensure that the
   attachment is valid.

2. It stores a bunch of state about the attachment being requested in
   the verifier environment and struct bpf_prog objects.

3. It allocates a trampoline for the attachment.

This patch splits out (1.) and (3.) into separate functions which will
perform the checks, but return the computed values instead of directly
modifying the environment. This is done in preparation for reusing the
checks when the actual attachment is happening, which will allow tracing
programs to have multiple (compatible) attachments.

This also fixes a bug where a bunch of checks were skipped if a trampoline
already existed for the tracing target.

Fixes: 6ba43b761c ("bpf: Attachment verification for BPF_MODIFY_RETURN")
Fixes: 1e6c62a882 ("bpf: Introduce sleepable BPF programs")
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-09-28 17:10:34 -07:00
Toke Høiland-Jørgensen efc68158c4 bpf: change logging calls from verbose() to bpf_log() and use log pointer
In preparation for moving code around, change a bunch of references to
env->log (and the verbose() logging helper) to use bpf_log() and a direct
pointer to struct bpf_verifier_log. While we're touching the function
signature, mark the 'prog' argument to bpf_check_type_match() as const.

Also enhance the bpf_verifier_log_needed() check to handle NULL pointers
for the log struct so we can re-use the code with logging disabled.

Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-09-28 17:09:59 -07:00
Toke Høiland-Jørgensen 1af9270e90 bpf: disallow attaching modify_return tracing functions to other BPF programs
From the checks and commit messages for modify_return, it seems it was
never the intention that it should be possible to attach a tracing program
with expected_attach_type == BPF_MODIFY_RETURN to another BPF program.
However, check_attach_modify_return() will only look at the function name,
so if the target function starts with "security_", the attach will be
allowed even for bpf2bpf attachment.

Fix this oversight by also blocking the modification if a target program is
supplied.

Fixes: 18644cec71 ("bpf: Fix use-after-free in fmod_ret check")
Fixes: 6ba43b761c ("bpf: Attachment verification for BPF_MODIFY_RETURN")
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-09-28 17:08:07 -07:00
Lorenz Bauer 6550f2dddf bpf: sockmap: Enable map_update_elem from bpf_iter
Allow passing a pointer to a BTF struct sock_common* when updating
a sockmap or sockhash. Since BTF pointers can fault and therefore be
NULL at runtime we need to add an additional !sk check to
sock_map_update_elem. Since we may be passed a request or timewait
socket we also need to check sk_fullsock. Doing this allows calling
map_update_elem on sockmap from bpf_iter context, which uses
BTF pointers.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200928090805.23343-2-lmb@cloudflare.com
2020-09-28 16:40:46 -07:00
Lorenzo Bianconi efa90b5093 bpf, cpumap: Remove rcpu pointer from cpu_map_build_skb signature
Get rid of bpf_cpu_map_entry pointer in cpu_map_build_skb routine
signature since it is no longer needed.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/33cb9b7dc447de3ea6fd6ce713ac41bca8794423.1601292015.git.lorenzo@kernel.org
2020-09-28 23:30:42 +02:00
Song Liu 1b4d60ec16 bpf: Enable BPF_PROG_TEST_RUN for raw_tracepoint
Add .test_run for raw_tracepoint. Also, introduce a new feature that runs
the target program on a specific CPU. This is achieved by a new flag in
bpf_attr.test, BPF_F_TEST_RUN_ON_CPU. When this flag is set, the program
is triggered on cpu with id bpf_attr.test.cpu. This feature is needed for
BPF programs that handle perf_event and other percpu resources, as the
program can access these resource locally.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200925205432.1777-2-songliubraving@fb.com
2020-09-28 21:52:36 +02:00
Xiaoyi Chen 55c4478a8f PM: hibernate: Batch hibernate and resume IO requests
Hibernate and resume process submits individual IO requests for each page
of the data, so use blk_plug to improve the batching of these requests.

Testing this change with hibernate and resumes consistently shows merging
of the IO requests and more than an order of magnitude improvement in
hibernate and resume speed is observed.

One hibernate and resume cycle for 16GB RAM out of 32GB in use takes
around 21 minutes before the change, and 1 minutes after the change on
a system with limited storage IOPS.

Signed-off-by: Xiaoyi Chen <cxiaoyi@amazon.com>
Co-Developed-by: Anchal Agarwal <anchalag@amazon.com>
Signed-off-by: Anchal Agarwal <anchalag@amazon.com>
[ rjw: Subject and changelog edits, white space damage fixes ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-09-28 15:58:18 +02:00
Daniel Thompson f2d10ff4a9 kgdb: Honour the kprobe blocklist when setting breakpoints
Currently kgdb has absolutely no safety rails in place to discourage or
prevent a user from placing a breakpoint in dangerous places such as
the debugger's own trap entry/exit and other places where it is not safe
to take synchronous traps.

Introduce a new config symbol KGDB_HONOUR_BLOCKLIST and modify the
default implementation of kgdb_validate_break_address() so that we use
the kprobe blocklist to prohibit instrumentation of critical functions
if the config symbol is set. The config symbol dependencies are set to
ensure that the blocklist will be enabled by default if we enable KGDB
and are compiling for an architecture where we HAVE_KPROBES.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20200927211531.1380577-2-daniel.thompson@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-09-28 12:14:08 +01:00
Peter Xu 7a4830c380 mm/fork: Pass new vma pointer into copy_page_range()
This prepares for the future work to trigger early cow on pinned pages
during fork().

No functional change intended.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-27 11:21:35 -07:00
Peter Xu 008cfe4418 mm: Introduce mm_struct.has_pinned
(Commit message majorly collected from Jason Gunthorpe)

Reduce the chance of false positive from page_maybe_dma_pinned() by
keeping track if the mm_struct has ever been used with pin_user_pages().
This allows cases that might drive up the page ref_count to avoid any
penalty from handling dma_pinned pages.

Future work is planned, to provide a more sophisticated solution, likely
to turn it into a real counter.  For now, make it atomic_t but use it as
a boolean for simplicity.

Suggested-by: Jason Gunthorpe <jgg@ziepe.ca>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-27 11:21:35 -07:00
John Fastabend 4fbb38a3b2 bpf, verifier: Remove redundant var_off.value ops in scalar known reg cases
In BPF_AND and BPF_OR alu cases we have this pattern when the src and dst
tnum is a constant.

 1 dst_reg->var_off = tnum_[op](dst_reg->var_off, src_reg.var_off)
 2 scalar32_min_max_[op]
 3       if (known) return
 4 scalar_min_max_[op]
 5       if (known)
 6          __mark_reg_known(dst_reg,
                   dst_reg->var_off.value [op] src_reg.var_off.value)

The result is in 1 we calculate the var_off value and store it in the
dst_reg. Then in 6 we duplicate this logic doing the op again on the
value.

The duplication comes from the the tnum_[op] handlers because they have
already done the value calcuation. For example this is tnum_and().

 struct tnum tnum_and(struct tnum a, struct tnum b)
 {
	u64 alpha, beta, v;

	alpha = a.value | a.mask;
	beta = b.value | b.mask;
	v = a.value & b.value;
	return TNUM(v, alpha & beta & ~v);
 }

So lets remove the redundant op calculation. Its confusing for readers
and unnecessary. Its also not harmful because those ops have the
property, r1 & r1 = r1 and r1 | r1 = r1.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-09-25 16:47:21 -07:00
Martin KaFai Lau 592a349864 bpf: Change bpf_sk_storage_*() to accept ARG_PTR_TO_BTF_ID_SOCK_COMMON
This patch changes the bpf_sk_storage_*() to take
ARG_PTR_TO_BTF_ID_SOCK_COMMON such that they will work with the pointer
returned by the bpf_skc_to_*() helpers also.

A micro benchmark has been done on a "cgroup_skb/egress" bpf program
which does a bpf_sk_storage_get().  It was driven by netperf doing
a 4096 connected UDP_STREAM test with 64bytes packet.
The stats from "kernel.bpf_stats_enabled" shows no meaningful difference.

The sk_storage_get_btf_proto, sk_storage_delete_btf_proto,
btf_sk_storage_get_proto, and btf_sk_storage_delete_proto are
no longer needed, so they are removed.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Link: https://lore.kernel.org/bpf/20200925000402.3856307-1-kafai@fb.com
2020-09-25 13:58:01 -07:00
Martin KaFai Lau 1df8f55a37 bpf: Enable bpf_skc_to_* sock casting helper to networking prog type
There is a constant need to add more fields into the bpf_tcp_sock
for the bpf programs running at tc, sock_ops...etc.

A current workaround could be to use bpf_probe_read_kernel().  However,
other than making another helper call for reading each field and missing
CO-RE, it is also not as intuitive to use as directly reading
"tp->lsndtime" for example.  While already having perfmon cap to do
bpf_probe_read_kernel(), it will be much easier if the bpf prog can
directly read from the tcp_sock.

This patch tries to do that by using the existing casting-helpers
bpf_skc_to_*() whose func_proto returns a btf_id.  For example, the
func_proto of bpf_skc_to_tcp_sock returns the btf_id of the
kernel "struct tcp_sock".

These helpers are also added to is_ptr_cast_function().
It ensures the returning reg (BPF_REF_0) will also carries the ref_obj_id.
That will keep the ref-tracking works properly.

The bpf_skc_to_* helpers are made available to most of the bpf prog
types in filter.c. The bpf_skc_to_* helpers will be limited by
perfmon cap.

This patch adds a ARG_PTR_TO_BTF_ID_SOCK_COMMON.  The helper accepting
this arg can accept a btf-id-ptr (PTR_TO_BTF_ID + &btf_sock_ids[BTF_SOCK_TYPE_SOCK_COMMON])
or a legacy-ctx-convert-skc-ptr (PTR_TO_SOCK_COMMON).  The bpf_skc_to_*()
helpers are changed to take ARG_PTR_TO_BTF_ID_SOCK_COMMON such that
they will accept pointer obtained from skb->sk.

Instead of specifying both arg_type and arg_btf_id in the same func_proto
which is how the current ARG_PTR_TO_BTF_ID does, the arg_btf_id of
the new ARG_PTR_TO_BTF_ID_SOCK_COMMON is specified in the
compatible_reg_types[] in verifier.c.  The reason is the arg_btf_id is
always the same.  Discussion in this thread:
https://lore.kernel.org/bpf/20200922070422.1917351-1-kafai@fb.com/

The ARG_PTR_TO_BTF_ID_ part gives a clear expectation that the helper is
expecting a PTR_TO_BTF_ID which could be NULL.  This is the same
behavior as the existing helper taking ARG_PTR_TO_BTF_ID.

The _SOCK_COMMON part means the helper is also expecting the legacy
SOCK_COMMON pointer.

By excluding the _OR_NULL part, the bpf prog cannot call helper
with a literal NULL which doesn't make sense in most cases.
e.g. bpf_skc_to_tcp_sock(NULL) will be rejected.  All PTR_TO_*_OR_NULL
reg has to do a NULL check first before passing into the helper or else
the bpf prog will be rejected.  This behavior is nothing new and
consistent with the current expectation during bpf-prog-load.

[ ARG_PTR_TO_BTF_ID_SOCK_COMMON will be used to replace
  ARG_PTR_TO_SOCK* of other existing helpers later such that
  those existing helpers can take the PTR_TO_BTF_ID returned by
  the bpf_skc_to_*() helpers.

  The only special case is bpf_sk_lookup_assign() which can accept a
  literal NULL ptr.  It has to be handled specially in another follow
  up patch if there is a need (e.g. by renaming ARG_PTR_TO_SOCKET_OR_NULL
  to ARG_PTR_TO_BTF_ID_SOCK_COMMON_OR_NULL). ]

[ When converting the older helpers that take ARG_PTR_TO_SOCK* in
  the later patch, if the kernel does not support BTF,
  ARG_PTR_TO_BTF_ID_SOCK_COMMON will behave like ARG_PTR_TO_SOCK_COMMON
  because no reg->type could have PTR_TO_BTF_ID in this case.

  It is not a concern for the newer-btf-only helper like the bpf_skc_to_*()
  here though because these helpers must require BTF vmlinux to begin
  with. ]

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200925000350.3855720-1-kafai@fb.com
2020-09-25 13:58:01 -07:00
Martin KaFai Lau a968d5e277 bpf: Move the PTR_TO_BTF_ID check to check_reg_type()
check_reg_type() checks whether a reg can be used as an arg of a
func_proto.  For PTR_TO_BTF_ID, the check is actually not
completely done until the reg->btf_id is pointing to a
kernel struct that is acceptable by the func_proto.

Thus, this patch moves the btf_id check into check_reg_type().
"arg_type" and "arg_btf_id" are passed to check_reg_type() instead of
"compatible".  The compatible_reg_types[] usage is localized in
check_reg_type() now.

The "if (!btf_id) verbose(...); " is also removed since it won't happen.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200925000344.3854828-1-kafai@fb.com
2020-09-25 13:58:01 -07:00
Masami Hiramatsu 720dee53ad tracing/boot: Initialize per-instance event list in early boot
Initialize per-instance event list in early boot time (before
initializing instance directory on tracefs). This fixes boot-time
tracing to correctly handle the boot-time per-instance settings.

Link: https://lkml.kernel.org/r/160096560826.182763.17110991546046128881.stgit@devnote2

Fixes: 4114fbfd02 ("tracing: Enable creating new instance early boot")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-25 15:36:03 -04:00
Linus Torvalds 15083aa025 Power management fixes for 5.9-rc7
- Export rcu_idle_{enter,exit} to modules to fix build issues
    introduced by recent RCU-lockdep fixes (Borislav Petkov).
 
  - Add missing return statement to a stub function in the ACPI
    processor driver to fix a build issue introduced by recent
    RCU-lockdep fixes (Rafael Wysocki).
 
  - Fix recently introduced suspicious RCU usage warnings in the PSCI
    cpuidle driver and drop stale comments regarding RCU_NONIDLE()
    usage from enter_s2idle_proper() (Ulf Hansson).
 
  - Fix error code path in the tegra30 devfreq driver (Dan Carpenter).
 
  - Add missing information to devfreq_summary debugfs (Chanwoo Choi).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAl9uHyQSHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRxnx8P/Arz1UzuJVPla7JMp/xCwxAHPcuI/0yP
 U1oM5CBtFN68kWaA+tIjhEfH6nw/7dOpnF1YpEkhoVZBLzM48AYbBDhtqVHYI8vq
 6HRnntoTGYCxGSEsG1aTLdEMa1htfqLu6Q+gdrGZKhRygW4LMdiCnWBcGrzMdPil
 VVkAmf3bKp9gR1hibNhB475uQs2+ZD0LOBw2pKvn+v2XRzgj7lltpDfkjvZGuzwy
 jTvt5GMffcyoD7ghMU5I2xH8e7egGVdkxqNFukz7w/5zDRmbJ6T0C0IbSUkHzuvE
 79owcQcsrMNvTXnSGAIMpv30gKOCcLRY/mQWNDeduqF34Rrv0I4GOUKaf6fOdm50
 R2WHvxAFDw+T3ExP75anacQw/daladN6lkufxWjFvvYe4aqPaBt6YF6V11gKOGft
 xP2B6h1XHP7RwFr8IhVrcKuRN4xmXLqcipfja+rpO0h4Wcu8asOvhdxdmS/BNANc
 wjJtBIykB5vFnaRUMwmPFWINWzgsBZ7h5QzZTvytD8g4sFX63/XlezWwYvC7w489
 Qg/l7r86fJD5C/TOpUipK320mj/5Ndypgpu5U01salE/XYgWwIRy2a6ETk4tzTBC
 VpXNRiWPolikpjEqm7arCjm0l7oNOQypauN6yI4joWjWt2KttNAvl7HrY/crzLqT
 FL1M9LNJmAlS
 =lea/
 -----END PGP SIGNATURE-----

Merge tag 'pm-5.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix more fallout of recent RCU-lockdep changes in CPU idle code
  and two devfreq issues.

  Specifics:

   - Export rcu_idle_{enter,exit} to modules to fix build issues
     introduced by recent RCU-lockdep fixes (Borislav Petkov)

   - Add missing return statement to a stub function in the ACPI
     processor driver to fix a build issue introduced by recent
     RCU-lockdep fixes (Rafael Wysocki)

   - Fix recently introduced suspicious RCU usage warnings in the PSCI
     cpuidle driver and drop stale comments regarding RCU_NONIDLE()
     usage from enter_s2idle_proper() (Ulf Hansson)

   - Fix error code path in the tegra30 devfreq driver (Dan Carpenter)

   - Add missing information to devfreq_summary debugfs (Chanwoo Choi)"

* tag 'pm-5.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: processor: Fix build for ARCH_APICTIMER_STOPS_ON_C3 unset
  PM / devfreq: tegra30: Disable clock on error in probe
  PM / devfreq: Add timer type to devfreq_summary debugfs
  cpuidle: Drop misleading comments about RCU usage
  cpuidle: psci: Fix suspicious RCU usage
  rcu/tree: Export rcu_idle_{enter,exit} to modules
2020-09-25 10:39:22 -07:00
Christoph Hellwig fa01b1e973 block: add a bdev_is_partition helper
Add a littler helper to make the somewhat arcane bd_contains checks a
little more obvious.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-25 08:18:57 -06:00
Peter Oskolkov 2a36ab717e rseq/membarrier: Add MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ
This patchset is based on Google-internal RSEQ work done by Paul
Turner and Andrew Hunter.

When working with per-CPU RSEQ-based memory allocations, it is
sometimes important to make sure that a global memory location is no
longer accessed from RSEQ critical sections. For example, there can be
two per-CPU lists, one is "active" and accessed per-CPU, while another
one is inactive and worked on asynchronously "off CPU" (e.g.  garbage
collection is performed). Then at some point the two lists are
swapped, and a fast RCU-like mechanism is required to make sure that
the previously active list is no longer accessed.

This patch introduces such a mechanism: in short, membarrier() syscall
issues an IPI to a CPU, restarting a potentially active RSEQ critical
section on the CPU.

Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lkml.kernel.org/r/20200923233618.2572849-1-posk@google.com
2020-09-25 14:23:27 +02:00
Barry Song 233e7aca4c sched/fair: Use dst group while checking imbalance for NUMA balancer
Barry Song noted the following

	Something is wrong. In find_busiest_group(), we are checking if
	src has higher load, however, in task_numa_find_cpu(), we are
	checking if dst will have higher load after balancing. It seems
	it is not sensible to check src.

	It maybe cause wrong imbalance value, for example,

	if dst_running = env->dst_stats.nr_running + 1 results in 3 or
	above, and src_running = env->src_stats.nr_running - 1 results
	in 1;

	The current code is thinking imbalance as 0 since src_running is
	smaller than 2.  This is inconsistent with load balancer.

Basically, in find_busiest_group(), the NUMA imbalance is ignored if moving
a task "from an almost idle domain" to a "domain with spare capacity". This
patch forbids movement "from a misplaced domain" to "an almost idle domain"
as that is closer to what the CPU load balancer expects.

This patch is not a universal win. The old behaviour was intended to allow
a task from an almost idle NUMA node to migrate to its preferred node if
the destination had capacity but there are corner cases.  For example,
a NAS compute load could be parallelised to use 1/3rd of available CPUs
but not all those potential tasks are active at all times allowing this
logic to trigger. An obvious example is specjbb 2005 running various
numbers of warehouses on a 2 socket box with 80 cpus.

specjbb
                               5.9.0-rc4              5.9.0-rc4
                                 vanilla        dstbalance-v1r1
Hmean     tput-1     46425.00 (   0.00%)    43394.00 *  -6.53%*
Hmean     tput-2     98416.00 (   0.00%)    96031.00 *  -2.42%*
Hmean     tput-3    150184.00 (   0.00%)   148783.00 *  -0.93%*
Hmean     tput-4    200683.00 (   0.00%)   197906.00 *  -1.38%*
Hmean     tput-5    236305.00 (   0.00%)   245549.00 *   3.91%*
Hmean     tput-6    281559.00 (   0.00%)   285692.00 *   1.47%*
Hmean     tput-7    338558.00 (   0.00%)   334467.00 *  -1.21%*
Hmean     tput-8    340745.00 (   0.00%)   372501.00 *   9.32%*
Hmean     tput-9    424343.00 (   0.00%)   413006.00 *  -2.67%*
Hmean     tput-10   421854.00 (   0.00%)   434261.00 *   2.94%*
Hmean     tput-11   493256.00 (   0.00%)   485330.00 *  -1.61%*
Hmean     tput-12   549573.00 (   0.00%)   529959.00 *  -3.57%*
Hmean     tput-13   593183.00 (   0.00%)   555010.00 *  -6.44%*
Hmean     tput-14   588252.00 (   0.00%)   599166.00 *   1.86%*
Hmean     tput-15   623065.00 (   0.00%)   642713.00 *   3.15%*
Hmean     tput-16   703924.00 (   0.00%)   660758.00 *  -6.13%*
Hmean     tput-17   666023.00 (   0.00%)   697675.00 *   4.75%*
Hmean     tput-18   761502.00 (   0.00%)   758360.00 *  -0.41%*
Hmean     tput-19   796088.00 (   0.00%)   798368.00 *   0.29%*
Hmean     tput-20   733564.00 (   0.00%)   823086.00 *  12.20%*
Hmean     tput-21   840980.00 (   0.00%)   856711.00 *   1.87%*
Hmean     tput-22   804285.00 (   0.00%)   872238.00 *   8.45%*
Hmean     tput-23   795208.00 (   0.00%)   889374.00 *  11.84%*
Hmean     tput-24   848619.00 (   0.00%)   966783.00 *  13.92%*
Hmean     tput-25   750848.00 (   0.00%)   903790.00 *  20.37%*
Hmean     tput-26   780523.00 (   0.00%)   962254.00 *  23.28%*
Hmean     tput-27  1042245.00 (   0.00%)   991544.00 *  -4.86%*
Hmean     tput-28  1090580.00 (   0.00%)  1035926.00 *  -5.01%*
Hmean     tput-29   999483.00 (   0.00%)  1082948.00 *   8.35%*
Hmean     tput-30  1098663.00 (   0.00%)  1113427.00 *   1.34%*
Hmean     tput-31  1125671.00 (   0.00%)  1134175.00 *   0.76%*
Hmean     tput-32   968167.00 (   0.00%)  1250286.00 *  29.14%*
Hmean     tput-33  1077676.00 (   0.00%)  1060893.00 *  -1.56%*
Hmean     tput-34  1090538.00 (   0.00%)  1090933.00 *   0.04%*
Hmean     tput-35   967058.00 (   0.00%)  1107421.00 *  14.51%*
Hmean     tput-36  1051745.00 (   0.00%)  1210663.00 *  15.11%*
Hmean     tput-37  1019465.00 (   0.00%)  1351446.00 *  32.56%*
Hmean     tput-38  1083102.00 (   0.00%)  1064541.00 *  -1.71%*
Hmean     tput-39  1232990.00 (   0.00%)  1303623.00 *   5.73%*
Hmean     tput-40  1175542.00 (   0.00%)  1340943.00 *  14.07%*
Hmean     tput-41  1127826.00 (   0.00%)  1339492.00 *  18.77%*
Hmean     tput-42  1198313.00 (   0.00%)  1411023.00 *  17.75%*
Hmean     tput-43  1163733.00 (   0.00%)  1228253.00 *   5.54%*
Hmean     tput-44  1305562.00 (   0.00%)  1357886.00 *   4.01%*
Hmean     tput-45  1326752.00 (   0.00%)  1406061.00 *   5.98%*
Hmean     tput-46  1339424.00 (   0.00%)  1418451.00 *   5.90%*
Hmean     tput-47  1415057.00 (   0.00%)  1381570.00 *  -2.37%*
Hmean     tput-48  1392003.00 (   0.00%)  1421167.00 *   2.10%*
Hmean     tput-49  1408374.00 (   0.00%)  1418659.00 *   0.73%*
Hmean     tput-50  1359822.00 (   0.00%)  1391070.00 *   2.30%*
Hmean     tput-51  1414246.00 (   0.00%)  1392679.00 *  -1.52%*
Hmean     tput-52  1432352.00 (   0.00%)  1354020.00 *  -5.47%*
Hmean     tput-53  1387563.00 (   0.00%)  1409563.00 *   1.59%*
Hmean     tput-54  1406420.00 (   0.00%)  1388711.00 *  -1.26%*
Hmean     tput-55  1438804.00 (   0.00%)  1387472.00 *  -3.57%*
Hmean     tput-56  1399465.00 (   0.00%)  1400296.00 *   0.06%*
Hmean     tput-57  1428132.00 (   0.00%)  1396399.00 *  -2.22%*
Hmean     tput-58  1432385.00 (   0.00%)  1386253.00 *  -3.22%*
Hmean     tput-59  1421612.00 (   0.00%)  1371416.00 *  -3.53%*
Hmean     tput-60  1429423.00 (   0.00%)  1389412.00 *  -2.80%*
Hmean     tput-61  1396230.00 (   0.00%)  1351122.00 *  -3.23%*
Hmean     tput-62  1418396.00 (   0.00%)  1383098.00 *  -2.49%*
Hmean     tput-63  1409918.00 (   0.00%)  1374662.00 *  -2.50%*
Hmean     tput-64  1410236.00 (   0.00%)  1376216.00 *  -2.41%*
Hmean     tput-65  1396405.00 (   0.00%)  1364418.00 *  -2.29%*
Hmean     tput-66  1395975.00 (   0.00%)  1357326.00 *  -2.77%*
Hmean     tput-67  1392986.00 (   0.00%)  1349642.00 *  -3.11%*
Hmean     tput-68  1386541.00 (   0.00%)  1343261.00 *  -3.12%*
Hmean     tput-69  1374407.00 (   0.00%)  1342588.00 *  -2.32%*
Hmean     tput-70  1377513.00 (   0.00%)  1334654.00 *  -3.11%*
Hmean     tput-71  1369319.00 (   0.00%)  1334952.00 *  -2.51%*
Hmean     tput-72  1354635.00 (   0.00%)  1329005.00 *  -1.89%*
Hmean     tput-73  1350933.00 (   0.00%)  1318942.00 *  -2.37%*
Hmean     tput-74  1351714.00 (   0.00%)  1316347.00 *  -2.62%*
Hmean     tput-75  1352198.00 (   0.00%)  1309974.00 *  -3.12%*
Hmean     tput-76  1349490.00 (   0.00%)  1286064.00 *  -4.70%*
Hmean     tput-77  1336131.00 (   0.00%)  1303684.00 *  -2.43%*
Hmean     tput-78  1308896.00 (   0.00%)  1271024.00 *  -2.89%*
Hmean     tput-79  1326703.00 (   0.00%)  1290862.00 *  -2.70%*
Hmean     tput-80  1336199.00 (   0.00%)  1291629.00 *  -3.34%*

The performance at the mid-point is better but not universally better. The
patch is a mixed bag depending on the workload, machine and overall
levels of utilisation. Sometimes it's better (sometimes much better),
other times it is worse (sometimes much worse). Given that there isn't a
universally good decision in this section and more people seem to prefer
the patch then it may be best to keep the LB decisions consistent and
revisit imbalance handling when the load balancer code changes settle down.

Jirka Hladky added the following observation.

	Our results are mostly in line with what you see. We observe
	big gains (20-50%) when the system is loaded to 1/3 of the
	maximum capacity and mixed results at the full load - some
	workloads benefit from the patch at the full load, others not,
	but performance changes at the full load are mostly within the
	noise of results (+/-5%). Overall, we think this patch is helpful.

[mgorman@techsingularity.net: Rewrote changelog]
Fixes: fb86f5b211 ("sched/numa: Use similar logic to the load balancer for moving between domains with spare capacity")
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200921221849.GI3179@techsingularity.net
2020-09-25 14:23:26 +02:00
Vincent Guittot 6e7499135d sched/fair: Reduce busy load balance interval
The busy_factor, which increases load balance interval when a cpu is busy,
is set to 32 by default. This value generates some huge LB interval on
large system like the THX2 made of 2 node x 28 cores x 4 threads.
For such system, the interval increases from 112ms to 3584ms at MC level.
And from 228ms to 7168ms at NUMA level.

Even on smaller system, a lower busy factor has shown improvement on the
fair distribution of the running time so let reduce it for all.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Link: https://lkml.kernel.org/r/20200921072424.14813-5-vincent.guittot@linaro.org
2020-09-25 14:23:26 +02:00
Vincent Guittot e4d32e4d54 sched/fair: Minimize concurrent LBs between domain level
sched domains tend to trigger simultaneously the load balance loop but
the larger domains often need more time to collect statistics. This
slowness makes the larger domain trying to detach tasks from a rq whereas
tasks already migrated somewhere else at a sub-domain level. This is not
a real problem for idle LB because the period of smaller domains will
increase with its CPUs being busy and this will let time for higher ones
to pulled tasks. But this becomes a problem when all CPUs are already busy
because all domains stay synced when they trigger their LB.

A simple way to minimize simultaneous LB of all domains is to decrement the
the busy interval by 1 jiffies. Because of the busy_factor, the interval of
larger domain will not be a multiple of smaller ones anymore.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Link: https://lkml.kernel.org/r/20200921072424.14813-4-vincent.guittot@linaro.org
2020-09-25 14:23:26 +02:00
Vincent Guittot 2208cdaa56 sched/fair: Reduce minimal imbalance threshold
The 25% default imbalance threshold for DIE and NUMA domain is large
enough to generate significant unfairness between threads. A typical
example is the case of 11 threads running on 2x4 CPUs. The imbalance of
20% between the 2 groups of 4 cores is just low enough to not trigger
the load balance between the 2 groups. We will have always the same 6
threads on one group of 4 CPUs and the other 5 threads on the other
group of CPUS. With a fair time sharing in each group, we ends up with
+20% running time for the group of 5 threads.

Consider decreasing the imbalance threshold for overloaded case where we
use the load to balance task and to ensure fair time sharing.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Acked-by: Hillf Danton <hdanton@sina.com>
Link: https://lkml.kernel.org/r/20200921072424.14813-3-vincent.guittot@linaro.org
2020-09-25 14:23:26 +02:00
Vincent Guittot 5a7f555904 sched/fair: Relax constraint on task's load during load balance
Some UCs like 9 always running tasks on 8 CPUs can't be balanced and the
load balancer currently migrates the waiting task between the CPUs in an
almost random manner. The success of a rq pulling a task depends of the
value of nr_balance_failed of its domains and its ability to be faster
than others to detach it. This behavior results in an unfair distribution
of the running time between tasks because some CPUs will run most of the
time, if not always, the same task whereas others will share their time
between several tasks.

Instead of using nr_balance_failed as a boolean to relax the condition
for detaching task, the LB will use nr_balanced_failed to relax the
threshold between the tasks'load and the imbalance. This mecanism
prevents the same rq or domain to always win the load balance fight.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Link: https://lkml.kernel.org/r/20200921072424.14813-2-vincent.guittot@linaro.org
2020-09-25 14:23:25 +02:00
Xianting Tian fe7491580d sched/fair: Remove the force parameter of update_tg_load_avg()
In the file fair.c, sometims update_tg_load_avg(cfs_rq, 0) is used,
sometimes update_tg_load_avg(cfs_rq, false) is used.
update_tg_load_avg() has the parameter force, but in current code,
it never set 1 or true to it, so remove the force parameter.

Signed-off-by: Xianting Tian <tian.xianting@h3c.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200924014755.36253-1-tian.xianting@h3c.com
2020-09-25 14:23:25 +02:00
Xunlei Pang df3cb4ea1f sched/fair: Fix wrong cpu selecting from isolated domain
We've met problems that occasionally tasks with full cpumask
(e.g. by putting it into a cpuset or setting to full affinity)
were migrated to our isolated cpus in production environment.

After some analysis, we found that it is due to the current
select_idle_smt() not considering the sched_domain mask.

Steps to reproduce on my 31-CPU hyperthreads machine:
1. with boot parameter: "isolcpus=domain,2-31"
   (thread lists: 0,16 and 1,17)
2. cgcreate -g cpu:test; cgexec -g cpu:test "test_threads"
3. some threads will be migrated to the isolated cpu16~17.

Fix it by checking the valid domain mask in select_idle_smt().

Fixes: 10e2f1acd0 ("sched/core: Rewrite and improve select_idle_siblings())
Reported-by: Wetp Zhang <wetp.zy@linux.alibaba.com>
Signed-off-by: Xunlei Pang <xlpang@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jiang Biao <benbjiang@tencent.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/1600930127-76857-1-git-send-email-xlpang@linux.alibaba.com
2020-09-25 14:23:25 +02:00
YueHaibing 51bd5121c4 sched: Remove unused inline function uclamp_bucket_base_value()
There is no caller in tree, so can remove it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lkml.kernel.org/r/20200922132410.48440-1-yuehaibing@huawei.com
2020-09-25 14:23:25 +02:00
Daniel Bristot de Oliveira 2586af1ac1 sched/rt: Disable RT_RUNTIME_SHARE by default
The RT_RUNTIME_SHARE sched feature enables the sharing of rt_runtime
between CPUs, allowing a CPU to run a real-time task up to 100% of the
time while leaving more space for non-real-time tasks to run on the CPU
that lend rt_runtime.

The problem is that a CPU can easily borrow enough rt_runtime to allow
a spinning rt-task to run forever, starving per-cpu tasks like kworkers,
which are non-real-time by design.

This patch disables RT_RUNTIME_SHARE by default, avoiding this problem.
The feature will still be present for users that want to enable it,
though.

Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Wei Wang <wvw@google.com>
Link: https://lkml.kernel.org/r/b776ab46817e3db5d8ef79175fa0d71073c051c7.1600697903.git.bristot@redhat.com
2020-09-25 14:23:24 +02:00
Lucas Stach 46fcc4b00c sched/deadline: Fix stale throttling on de-/boosted tasks
When a boosted task gets throttled, what normally happens is that it's
immediately enqueued again with ENQUEUE_REPLENISH, which replenishes the
runtime and clears the dl_throttled flag. There is a special case however:
if the throttling happened on sched-out and the task has been deboosted in
the meantime, the replenish is skipped as the task will return to its
normal scheduling class. This leaves the task with the dl_throttled flag
set.

Now if the task gets boosted up to the deadline scheduling class again
while it is sleeping, it's still in the throttled state. The normal wakeup
however will enqueue the task with ENQUEUE_REPLENISH not set, so we don't
actually place it on the rq. Thus we end up with a task that is runnable,
but not actually on the rq and neither a immediate replenishment happens,
nor is the replenishment timer set up, so the task is stuck in
forever-throttled limbo.

Clear the dl_throttled flag before dropping back to the normal scheduling
class to fix this issue.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200831110719.2126930-1-l.stach@pengutronix.de
2020-09-25 14:23:24 +02:00
Vincent Guittot 8e0e0eda6a sched/numa: Use runnable_avg to classify node
Use runnable_avg to classify numa node state similarly to what is done for
normal load balancer. This helps to ensure that numa and normal balancers
use the same view of the state of the system.

Large arm64system: 2 nodes / 224 CPUs:

  hackbench -l (256000/#grp) -g #grp

  grp    tip/sched/core         +patchset              improvement
  1      14,008(+/- 4,99 %)     13,800(+/- 3.88 %)     1,48 %
  4       4,340(+/- 5.35 %)      4.283(+/- 4.85 %)     1,33 %
  16      3,357(+/- 0.55 %)      3.359(+/- 0.54 %)    -0,06 %
  32      3,050(+/- 0.94 %)      3.039(+/- 1,06 %)     0,38 %
  64      2.968(+/- 1,85 %)      3.006(+/- 2.92 %)    -1.27 %
  128     3,290(+/-12.61 %)      3,108(+/- 5.97 %)     5.51 %
  256     3.235(+/- 3.95 %)      3,188(+/- 2.83 %)     1.45 %

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mel Gorman <mgorman@suse.de>
Link: https://lkml.kernel.org/r/20200921072959.16317-1-vincent.guittot@linaro.org
2020-09-25 14:23:24 +02:00
Christoph Hellwig de7cf91776 dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods
This will allow IOMMU drivers to allocate non-contigous memory and
return a vmapped virtual address.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-25 06:20:47 +02:00
Christoph Hellwig efa70f2fdc dma-mapping: add a new dma_alloc_pages API
This API is the equivalent of alloc_pages, except that the returned memory
is guaranteed to be DMA addressable by the passed in device.  The
implementation will also be used to provide a more sensible replacement
for DMA_ATTR_NON_CONSISTENT flag.

Additionally dma_alloc_noncoherent is switched over to use dma_alloc_pages
as its backend.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> (MIPS part)
2020-09-25 06:20:47 +02:00
Christoph Hellwig 5a84292271 dma-mapping: remove dma_cache_sync
All users are gone now, remove the API.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> (MIPS part)
2020-09-25 06:20:46 +02:00
Christoph Hellwig 8c1c6c7588 Merge branch 'master' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into dma-mapping-for-next
Pull in the latest 5.9 tree for the commit to revert the
V4L2_FLAG_MEMORY_NON_CONSISTENT uapi addition.
2020-09-25 06:19:19 +02:00
Qianli Zhao b952caf2d5 timers: Mask invalid flags in do_init_timer()
do_init_timer() accepts any combination of timer flags handed in by the
caller without a sanity check, but only TIMER_DEFFERABLE, TIMER_PINNED and
TIMER_IRQSAFE are valid.

If the supplied flags have other bits set, this could result in
malfunction. If bits are set in TIMER_CPUMASK the first timer usage could
deference a cpu base which is outside the range of possible CPUs. If
TIMER_MIGRATION is set, then the switch_timer_base() will live lock.

Prevent that with a sanity check which warns when invalid flags are
supplied and masks them out.

[ tglx: Made it WARN_ON_ONCE() and added context to the changelog ]

Signed-off-by: Qianli Zhao <zhaoqianli@xiaomi.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/9d79a8aa4eb56713af7379f99f062dedabcde140.1597326756.git.zhaoqianli@xiaomi.com
2020-09-24 22:12:18 +02:00
Stephen Boyd f9e62f318f treewide: Make all debug_obj_descriptors const
This should make it harder for the kernel to corrupt the debug object
descriptor, used to call functions to fixup state and track debug objects,
by moving the structure to read-only memory.

Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200815004027.2046113-3-swboyd@chromium.org
2020-09-24 21:56:25 +02:00
Jarkko Sakkinen e9ffc8c1b8 kprobes: Use module_name() macro
It is advised to use module_name() macro instead of dereferencing mod->name
directly. This makes sense for consistencys sake and also it prevents a
hard dependency to CONFIG_MODULES.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lkml.kernel.org/r/20200818050857.117998-1-jarkko.sakkinen@linux.intel.com
2020-09-24 15:55:49 +02:00
Alexei Starovoitov 182bf3f3dd Merge branch 'rtt-speedup.2020.09.16a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into bpf-next
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-09-23 19:32:09 -07:00
Alexei Starovoitov f00f2f7fe8 Revert "bpf: Fix potential call bpf_link_free() in atomic context"
This reverts commit 31f23a6a18.

This change made many selftests/bpf flaky: flow_dissector, sk_lookup, sk_assign and others.
There was no issue in the code.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-09-23 19:14:11 -07:00
David S. Miller 6d772f328d Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-09-23

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

We've added 95 non-merge commits during the last 22 day(s) which contain
a total of 124 files changed, 4211 insertions(+), 2040 deletions(-).

The main changes are:

1) Full multi function support in libbpf, from Andrii.

2) Refactoring of function argument checks, from Lorenz.

3) Make bpf_tail_call compatible with functions (subprograms), from Maciej.

4) Program metadata support, from YiFei.

5) bpf iterator optimizations, from Yonghong.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-23 13:11:11 -07:00
Lorenz Bauer 0789e13bc3 bpf: Explicitly size compatible_reg_types
Arrays with designated initializers have an implicit length of the highest
initialized value plus one. I used this to ensure that newly added entries
in enum bpf_reg_type get a NULL entry in compatible_reg_types.

This is difficult to understand since it requires knowledge of the
peculiarities of designated initializers. Use __BPF_ARG_TYPE_MAX to size
the array instead.

Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200923160156.80814-1-lmb@cloudflare.com
2020-09-23 11:46:46 -07:00
Christoph Hellwig 36daaa98f7 PM: mm: cleanup swsusp_swap_check
Use blkdev_get_by_dev instead of bdget + blkdev_get.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-23 10:43:19 -06:00
Christoph Hellwig 21bd900572 mm: split swap_type_of
swap_type_of is used for two entirely different purposes:

 (1) check what swap type a given device/offset corresponds to
 (2) find the first available swap device that can be written to

Mixing both in a single function creates an unreadable mess.  Create two
separate functions instead, and switch both to pass a dev_t instead of
a struct block_device to further simplify the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-23 10:43:19 -06:00
Christoph Hellwig bb3247a399 PM: rewrite is_hibernate_resume_dev to not require an inode
Just check the dev_t to help simplifying the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-23 10:43:19 -06:00
David S. Miller 3ab0a7a0c3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Two minor conflicts:

1) net/ipv4/route.c, adding a new local variable while
   moving another local variable and removing it's
   initial assignment.

2) drivers/net/dsa/microchip/ksz9477.c, overlapping changes.
   One pretty prints the port mode differently, whilst another
   changes the driver to try and obtain the port mode from
   the port node rather than the switch node.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-22 16:45:34 -07:00