- Remove CONFIG_ENABLE_MUST_CHECK (Masahiro Yamada)
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Merge tag 'compiler-attributes-for-linus-v5.11' of git://github.com/ojeda/linux
Pull ENABLE_MUST_CHECK removal from Miguel Ojeda:
"Remove CONFIG_ENABLE_MUST_CHECK (Masahiro Yamada)"
Note that this removes the config option by making the must-check
unconditional, not by removing must check itself.
* tag 'compiler-attributes-for-linus-v5.11' of git://github.com/ojeda/linux:
Compiler Attributes: remove CONFIG_ENABLE_MUST_CHECK
We have a handful of new kernel features for 5.11:
* Support for the contiguous memory allocator.
* Support for IRQ Time Accounting
* Support for stack tracing
* Support for strict /dev/mem
* Support for kernel section protection
I'm being a bit conservative on the cutoff for this round due to the
timing, so this is all the new development I'm going to take for this
cycle (even if some of it probably normally would have been OK). There
are, however, some fixes on the list that I will likely be sending along
either later this week or early next week.
There is one issue in here: one of my test configurations
(PREEMPT{,_DEBUG}=y) fails to boot on QEMU 5.0.0 (from April) as of the
.text.init alignment patch. With any luck we'll sort out the issue, but
given how many bugs get fixed all over the place and how unrelated those
features seem my guess is that we're just running into something that's
been lurking for a while and has already been fixed in the newer QEMU
(though I wouldn't be surprised if it's one of these implicit
assumptions we have in the boot flow). If it was hardware I'd be
strongly inclined to look more closely, but given that users can upgrade
their simulators I'm less worried about it.
There are two merge conflicts, both in build files. They're both a bit
clunky: arch/riscv/Kconfig is out of order (I have a script that's
supposed to keep them in order, I'll fix it) and lib/Makefile is out of
order (though GENERIC_LIB here doesn't mean quite what it does above).
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Merge tag 'riscv-for-linus-5.11-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt:
"We have a handful of new kernel features for 5.11:
- Support for the contiguous memory allocator.
- Support for IRQ Time Accounting
- Support for stack tracing
- Support for strict /dev/mem
- Support for kernel section protection
I'm being a bit conservative on the cutoff for this round due to the
timing, so this is all the new development I'm going to take for this
cycle (even if some of it probably normally would have been OK). There
are, however, some fixes on the list that I will likely be sending
along either later this week or early next week.
There is one issue in here: one of my test configurations
(PREEMPT{,_DEBUG}=y) fails to boot on QEMU 5.0.0 (from April) as of
the .text.init alignment patch.
With any luck we'll sort out the issue, but given how many bugs get
fixed all over the place and how unrelated those features seem my
guess is that we're just running into something that's been lurking
for a while and has already been fixed in the newer QEMU (though I
wouldn't be surprised if it's one of these implicit assumptions we
have in the boot flow). If it was hardware I'd be strongly inclined to
look more closely, but given that users can upgrade their simulators
I'm less worried about it"
* tag 'riscv-for-linus-5.11-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
arm64: Use the generic devmem_is_allowed()
arm: Use the generic devmem_is_allowed()
RISC-V: Use the new generic devmem_is_allowed()
lib: Add a generic version of devmem_is_allowed()
riscv: Fixed kernel test robot warning
riscv: kernel: Drop unused clean rule
riscv: provide memmove implementation
RISC-V: Move dynamic relocation section under __init
RISC-V: Protect all kernel sections including init early
RISC-V: Align the .init.text section
RISC-V: Initialize SBI early
riscv: Enable ARCH_STACKWALK
riscv: Make stack walk callback consistent with generic code
riscv: Cleanup stacktrace
riscv: Add HAVE_IRQ_TIME_ACCOUNTING
riscv: Enable CMA support
riscv: Ignore Image.* and loader.bin
riscv: Clean up boot dir
riscv: Fix compressed Image formats build
RISC-V: Add kernel image sections to the resource tree
Test get_option() for a starter which is provided by cmdline.c.
[akpm@linux-foundation.org: fix warning by constifying cmdline_test_values]
[andriy.shevchenko@linux.intel.com: type of expected returned values should be int]
Link: https://lkml.kernel.org/r/20201116104244.15472-1-andriy.shevchenko@linux.intel.com
[andriy.shevchenko@linux.intel.com: provide meaningful MODULE_LICENSE()]
Link: https://lkml.kernel.org/r/20201116104257.15527-1-andriy.shevchenko@linux.intel.com
Link: https://lkml.kernel.org/r/20201112180732.75589-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Vitor Massaru Iha <vitor@massaru.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: David Gow <davidgow@google.com>
Cc: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Update ACPICA code in the kernel to upstream revision 20201113
with changes as follows:
* Add 5 new UUIDs to the known UUID table (Bob Moore).
* Remove extreaneous "the" in comments (Colin Ian King).
* Add function trace macros to improve debugging (Erik Kaneda).
* Fix interpreter memory leak (Erik Kaneda).
* Handle "orphan" _REG for GPIO OpRegions (Hans de Goede).
- Introduce resource_union() and resource_intersection() helpers
and clean up some resource-manipulation code with the help of
them (Andy Shevchenko).
- Revert problematic commit related to the handling of resources
in the ACPI core (Daniel Scally).
- Extend the ACPI device enumeration documentation and the
gpio-line-names _DSD property documentation, clean up the
latter (Flavio Suligoi).
- Clean up _DEP handling during device enumeration, modify the list
of _DEP exceptions and the handling of it and fix up terminology
related to _DEP (Hans de Goede, Rafael Wysocki).
- Eliminate in_interrupt() usage from the ACPI EC driver (Sebastian
Andrzej Siewior).
- Clean up the advance_transaction() routine and related code in
the ACPI EC driver (Rafael Wysocki).
- Add new backlight quirk for GIGABYTE GB-BXBT-2807 (Jasper
St. Pierre).
- Make assorted janitorial changes in several ACPI-related pieces
of code (Hanjun Guo, Jason Yan, Punit Agrawal).
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Merge tag 'acpi-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
"These update the ACPICA code in the kernel to upstream revision
20201113, fix and clean up some resources manipulation code, extend
the enumeration and gpio-line-names property documentation, clean up
the handling of _DEP during device enumeration, add a new backlight
DMI quirk, clean up transaction handling in the EC driver and make
some assorted janitorial changes.
Specifics:
- Update ACPICA code in the kernel to upstream revision 20201113 with
changes as follows:
* Add 5 new UUIDs to the known UUID table (Bob Moore)
* Remove extreaneous "the" in comments (Colin Ian King)
* Add function trace macros to improve debugging (Erik Kaneda)
* Fix interpreter memory leak (Erik Kaneda)
* Handle "orphan" _REG for GPIO OpRegions (Hans de Goede)
- Introduce resource_union() and resource_intersection() helpers and
clean up some resource-manipulation code with the help of them
(Andy Shevchenko)
- Revert problematic commit related to the handling of resources in
the ACPI core (Daniel Scally)
- Extend the ACPI device enumeration documentation and the
gpio-line-names _DSD property documentation, clean up the latter
(Flavio Suligoi)
- Clean up _DEP handling during device enumeration, modify the list
of _DEP exceptions and the handling of it and fix up terminology
related to _DEP (Hans de Goede, Rafael Wysocki)
- Eliminate in_interrupt() usage from the ACPI EC driver (Sebastian
Andrzej Siewior)
- Clean up the advance_transaction() routine and related code in the
ACPI EC driver (Rafael Wysocki)
- Add new backlight quirk for GIGABYTE GB-BXBT-2807 (Jasper St
Pierre)
- Make assorted janitorial changes in several ACPI-related pieces of
code (Hanjun Guo, Jason Yan, Punit Agrawal)"
* tag 'acpi-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (40 commits)
ACPI: scan: Fix up _DEP-related terminology with supplier/consumer
ACPI: scan: Drop INT3396 from acpi_ignore_dep_ids[]
ACPI: video: Add DMI quirk for GIGABYTE GB-BXBT-2807
Revert "ACPI / resources: Use AE_CTRL_TERMINATE to terminate resources walks"
ACPI: scan: Add PNP0D80 to the _DEP exceptions list
ACPI: scan: Call acpi_get_object_info() from acpi_add_single_object()
ACPI: scan: Add acpi_info_matches_hids() helper
ACPICA: Update version to 20201113
ACPICA: Interpreter: fix memory leak by using existing buffer
ACPICA: Add function trace macros to improve debugging
ACPICA: Also handle "orphan" _REG methods for GPIO OpRegions
ACPICA: Remove extreaneous "the" in comments
ACPICA: Add 5 new UUIDs to the known UUID table
resource: provide meaningful MODULE_LICENSE() in test suite
ASoC: Intel: catpt: Replace open coded variant of resource_intersection()
ACPI: processor: Drop duplicate setting of shared_cpu_map
ACPI: EC: Clean up status flags checks in advance_transaction()
ACPI: EC: Untangle error handling in advance_transaction()
ACPI: EC: Simplify error handling in advance_transaction()
ACPI: EC: Rename acpi_ec_is_gpe_raised()
...
Core:
- support "prefer busy polling" NAPI operation mode, where we defer softirq
for some time expecting applications to periodically busy poll
- AF_XDP: improve efficiency by more batching and hindering
the adjacency cache prefetcher
- af_packet: make packet_fanout.arr size configurable up to 64K
- tcp: optimize TCP zero copy receive in presence of partial or unaligned
reads making zero copy a performance win for much smaller messages
- XDP: add bulk APIs for returning / freeing frames
- sched: support fragmenting IP packets as they come out of conntrack
- net: allow virtual netdevs to forward UDP L4 and fraglist GSO skbs
BPF:
- BPF switch from crude rlimit-based to memcg-based memory accounting
- BPF type format information for kernel modules and related tracing
enhancements
- BPF implement task local storage for BPF LSM
- allow the FENTRY/FEXIT/RAW_TP tracing programs to use bpf_sk_storage
Protocols:
- mptcp: improve multiple xmit streams support, memory accounting and
many smaller improvements
- TLS: support CHACHA20-POLY1305 cipher
- seg6: add support for SRv6 End.DT4/DT6 behavior
- sctp: Implement RFC 6951: UDP Encapsulation of SCTP
- ppp_generic: add ability to bridge channels directly
- bridge: Connectivity Fault Management (CFM) support as is defined in
IEEE 802.1Q section 12.14.
Drivers:
- mlx5: make use of the new auxiliary bus to organize the driver internals
- mlx5: more accurate port TX timestamping support
- mlxsw:
- improve the efficiency of offloaded next hop updates by using
the new nexthop object API
- support blackhole nexthops
- support IEEE 802.1ad (Q-in-Q) bridging
- rtw88: major bluetooth co-existance improvements
- iwlwifi: support new 6 GHz frequency band
- ath11k: Fast Initial Link Setup (FILS)
- mt7915: dual band concurrent (DBDC) support
- net: ipa: add basic support for IPA v4.5
Refactor:
- a few pieces of in_interrupt() cleanup work from Sebastian Andrzej Siewior
- phy: add support for shared interrupts; get rid of multiple driver
APIs and have the drivers write a full IRQ handler, slight growth
of driver code should be compensated by the simpler API which
also allows shared IRQs
- add common code for handling netdev per-cpu counters
- move TX packet re-allocation from Ethernet switch tag drivers to
a central place
- improve efficiency and rename nla_strlcpy
- number of W=1 warning cleanups as we now catch those in a patchwork
build bot
Old code removal:
- wan: delete the DLCI / SDLA drivers
- wimax: move to staging
- wifi: remove old WDS wifi bridging support
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:
"Core:
- support "prefer busy polling" NAPI operation mode, where we defer
softirq for some time expecting applications to periodically busy
poll
- AF_XDP: improve efficiency by more batching and hindering the
adjacency cache prefetcher
- af_packet: make packet_fanout.arr size configurable up to 64K
- tcp: optimize TCP zero copy receive in presence of partial or
unaligned reads making zero copy a performance win for much smaller
messages
- XDP: add bulk APIs for returning / freeing frames
- sched: support fragmenting IP packets as they come out of conntrack
- net: allow virtual netdevs to forward UDP L4 and fraglist GSO skbs
BPF:
- BPF switch from crude rlimit-based to memcg-based memory accounting
- BPF type format information for kernel modules and related tracing
enhancements
- BPF implement task local storage for BPF LSM
- allow the FENTRY/FEXIT/RAW_TP tracing programs to use
bpf_sk_storage
Protocols:
- mptcp: improve multiple xmit streams support, memory accounting and
many smaller improvements
- TLS: support CHACHA20-POLY1305 cipher
- seg6: add support for SRv6 End.DT4/DT6 behavior
- sctp: Implement RFC 6951: UDP Encapsulation of SCTP
- ppp_generic: add ability to bridge channels directly
- bridge: Connectivity Fault Management (CFM) support as is defined
in IEEE 802.1Q section 12.14.
Drivers:
- mlx5: make use of the new auxiliary bus to organize the driver
internals
- mlx5: more accurate port TX timestamping support
- mlxsw:
- improve the efficiency of offloaded next hop updates by using
the new nexthop object API
- support blackhole nexthops
- support IEEE 802.1ad (Q-in-Q) bridging
- rtw88: major bluetooth co-existance improvements
- iwlwifi: support new 6 GHz frequency band
- ath11k: Fast Initial Link Setup (FILS)
- mt7915: dual band concurrent (DBDC) support
- net: ipa: add basic support for IPA v4.5
Refactor:
- a few pieces of in_interrupt() cleanup work from Sebastian Andrzej
Siewior
- phy: add support for shared interrupts; get rid of multiple driver
APIs and have the drivers write a full IRQ handler, slight growth
of driver code should be compensated by the simpler API which also
allows shared IRQs
- add common code for handling netdev per-cpu counters
- move TX packet re-allocation from Ethernet switch tag drivers to a
central place
- improve efficiency and rename nla_strlcpy
- number of W=1 warning cleanups as we now catch those in a patchwork
build bot
Old code removal:
- wan: delete the DLCI / SDLA drivers
- wimax: move to staging
- wifi: remove old WDS wifi bridging support"
* tag 'net-next-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1922 commits)
net: hns3: fix expression that is currently always true
net: fix proc_fs init handling in af_packet and tls
nfc: pn533: convert comma to semicolon
af_vsock: Assign the vsock transport considering the vsock address flags
af_vsock: Set VMADDR_FLAG_TO_HOST flag on the receive path
vsock_addr: Check for supported flag values
vm_sockets: Add VMADDR_FLAG_TO_HOST vsock flag
vm_sockets: Add flags field in the vsock address data structure
net: Disable NETIF_F_HW_TLS_TX when HW_CSUM is disabled
tcp: Add logic to check for SYN w/ data in tcp_simple_retransmit
net: mscc: ocelot: install MAC addresses in .ndo_set_rx_mode from process context
nfc: s3fwrn5: Release the nfc firmware
net: vxget: clean up sparse warnings
mlxsw: spectrum_router: Use eXtended mezzanine to offload IPv4 router
mlxsw: spectrum: Set KVH XLT cache mode for Spectrum2/3
mlxsw: spectrum_router_xm: Introduce basic XM cache flushing
mlxsw: reg: Add Router LPM Cache Enable Register
mlxsw: reg: Add Router LPM Cache ML Delete Register
mlxsw: spectrum_router_xm: Implement L-value tracking for M-index
mlxsw: reg: Add XM Router M Table Register
...
As part of adding STRICT_DEVMEM support to the RISC-V port, Zong provided an
implementation of devmem_is_allowed() that's exactly the same as the version in
a handful of other ports. Rather than duplicate code, I've put a generic
version of this in lib/ and used it for the RISC-V port.
* palmer/generic-devmem:
arm64: Use the generic devmem_is_allowed()
arm: Use the generic devmem_is_allowed()
RISC-V: Use the new generic devmem_is_allowed()
lib: Add a generic version of devmem_is_allowed()
As part of adding support for STRICT_DEVMEM to the RISC-V port, Zong
provided a devmem_is_allowed() implementation that's exactly the same as
all the others I checked. Instead I'm adding a generic version, which
will soon be used.
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Revert commit cebc04ba9a ("add CONFIG_ENABLE_MUST_CHECK").
A lot of warn_unused_result warnings existed in 2006, but until now
they have been fixed thanks to people doing allmodconfig tests.
Our goal is to always enable __must_check where appropriate, so this
CONFIG option is no longer needed.
I see a lot of defconfig (arch/*/configs/*_defconfig) files having:
# CONFIG_ENABLE_MUST_CHECK is not set
I did not touch them for now since it would be a big churn. If arch
maintainers want to clean them up, please go ahead.
While I was here, I also moved __must_check to compiler_attributes.h
from compiler_types.h
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
[Moved addition in compiler_attributes.h to keep it sorted]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
It turns out that usage of skb extensions can cause memory leaks. Ido
Schimmel reported: "[...] there are instances that blindly overwrite
'skb->extensions' by invoking skb_copy_header() after __alloc_skb()."
Therefore, give up on using skb extensions for KCOV handle, and instead
directly store kcov_handle in sk_buff.
Fixes: 6370cc3bbd ("net: add kcov handle to skb extensions")
Fixes: 85ce50d337 ("net: kcov: don't select SKB_EXTENSIONS when there is no NET")
Fixes: 97f53a08cb ("net: linux/skbuff.h: combine SKB_EXTENSIONS + KCOV handling")
Link: https://lore.kernel.org/linux-wireless/20201121160941.GA485907@shredder.lan/
Reported-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20201125224840.2014773-1-elver@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
CONFIG_DEBUG_KMAP_LOCAL, which is selected by CONFIG_DEBUG_HIGHMEM is only
providing guard pages, but does not provide a mechanism to enforce the
usage of the kmap_local() infrastructure.
Provide CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP which forces the temporary
mapping even for lowmem pages. This needs to be a seperate config switch
because this only works on architectures which do not have cache aliasing
problems.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20201118204007.028261233@linutronix.de
CONFIG_KMAP_LOCAL can be enabled by x86/32bit even if CONFIG_HIGHMEM is not
enabled for temporary MMIO space mappings.
Provide it as a seperate config option which depends on CONFIG_KMAP_LOCAL
and let CONFIG_DEBUG_HIGHMEM select it.
This won't increase the debug coverage of this significantly but it paves
the way to do so.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20201118204006.869487226@linutronix.de
Add test cases for newly added resource APIs.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-11-14
1) Add BTF generation for kernel modules and extend BTF infra in kernel
e.g. support for split BTF loading and validation, from Andrii Nakryiko.
2) Support for pointers beyond pkt_end to recognize LLVM generated patterns
on inlined branch conditions, from Alexei Starovoitov.
3) Implements bpf_local_storage for task_struct for BPF LSM, from KP Singh.
4) Enable FENTRY/FEXIT/RAW_TP tracing program to use the bpf_sk_storage
infra, from Martin KaFai Lau.
5) Add XDP bulk APIs that introduce a defer/flush mechanism to optimize the
XDP_REDIRECT path, from Lorenzo Bianconi.
6) Fix a potential (although rather theoretical) deadlock of hashtab in NMI
context, from Song Liu.
7) Fixes for cross and out-of-tree build of bpftool and runqslower allowing build
for different target archs on same source tree, from Jean-Philippe Brucker.
8) Fix error path in htab_map_alloc() triggered from syzbot, from Eric Dumazet.
9) Move functionality from test_tcpbpf_user into the test_progs framework so it
can run in BPF CI, from Alexander Duyck.
10) Lift hashtab key_size limit to be larger than MAX_BPF_STACK, from Florian Lehner.
Note that for the fix from Song we have seen a sparse report on context
imbalance which requires changes in sparse itself for proper annotation
detection where this is currently being discussed on linux-sparse among
developers [0]. Once we have more clarification/guidance after their fix,
Song will follow-up.
[0] https://lore.kernel.org/linux-sparse/CAHk-=wh4bx8A8dHnX612MsDO13st6uzAz1mJ1PaHHVevJx_ZCw@mail.gmail.com/T/https://lore.kernel.org/linux-sparse/20201109221345.uklbp3lzgq6g42zb@ltop.local/T/
* git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (66 commits)
net: mlx5: Add xdp tx return bulking support
net: mvpp2: Add xdp tx return bulking support
net: mvneta: Add xdp tx return bulking support
net: page_pool: Add bulk support for ptr_ring
net: xdp: Introduce bulking for xdp tx return path
bpf: Expose bpf_d_path helper to sleepable LSM hooks
bpf: Augment the set of sleepable LSM hooks
bpf: selftest: Use bpf_sk_storage in FENTRY/FEXIT/RAW_TP
bpf: Allow using bpf_sk_storage in FENTRY/FEXIT/RAW_TP
bpf: Rename some functions in bpf_sk_storage
bpf: Folding omem_charge() into sk_storage_charge()
selftests/bpf: Add asm tests for pkt vs pkt_end comparison.
selftests/bpf: Add skb_pkt_end test
bpf: Support for pointers beyond pkt_end.
tools/bpf: Always run the *-clean recipes
tools/bpf: Add bootstrap/ to .gitignore
bpf: Fix NULL dereference in bpf_task_storage
tools/bpftool: Fix build slowdown
tools/runqslower: Build bpftool using HOSTCC
tools/runqslower: Enable out-of-tree build
...
====================
Link: https://lore.kernel.org/r/20201114020819.29584-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Fix kconfig warning when CONFIG_NET is not set/enabled:
WARNING: unmet direct dependencies detected for SKB_EXTENSIONS
Depends on [n]: NET [=n]
Selected by [y]:
- KCOV [=y] && ARCH_HAS_KCOV [=y] && (CC_HAS_SANCOV_TRACE_PC [=y] || GCC_PLUGINS [=n])
Fixes: 6370cc3bbd ("net: add kcov handle to skb extensions")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Aleksandr Nogikh <nogikh@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20201110175746.11437-1-rdunlap@infradead.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Detect if pahole supports split BTF generation, and generate BTF for each
selected kernel module, if it does. This is exposed to Makefiles and C code as
CONFIG_DEBUG_INFO_BTF_MODULES flag.
Kernel module BTF has to be re-generated if either vmlinux's BTF changes or
module's .ko changes. To achieve that, I needed a helper similar to
if_changed, but that would allow to filter out vmlinux from the list of
updated dependencies for .ko building. I've put it next to the only place that
uses and needs it, but it might be a better idea to just add it along the
other if_changed variants into scripts/Kbuild.include.
Each kernel module's BTF deduplication is pretty fast, as it does only
incremental BTF deduplication on top of already deduplicated vmlinux BTF. To
show the added build time, I've first ran make only just built kernel (to
establish the baseline) and then forced only BTF re-generation, without
regenerating .ko files. The build was performed with -j60 parallelization on
56-core machine. The final time also includes bzImage building, so it's not
a pure BTF overhead.
$ time make -j60
...
make -j60 27.65s user 10.96s system 782% cpu 4.933 total
$ touch ~/linux-build/default/vmlinux && time make -j60
...
make -j60 123.69s user 27.85s system 1566% cpu 9.675 total
So 4.6 seconds real time, with noticeable part spent in compressed vmlinux and
bzImage building.
To show size savings, I've built my kernel configuration with about 700 kernel
modules with full BTF per each kernel module (without deduplicating against
vmlinux) and with split BTF against deduplicated vmlinux (approach in this
patch). Below are top 10 modules with biggest BTF sizes. And total size of BTF
data across all kernel modules.
It shows that split BTF "compresses" 115MB down to 5MB total. And the biggest
kernel modules get a downsize from 500-570KB down to 200-300KB.
FULL BTF
========
$ for f in $(find . -name '*.ko'); do size -A -d $f | grep BTF | awk '{print $2}'; done | awk '{ s += $1 } END { print s }'
115710691
$ for f in $(find . -name '*.ko'); do printf "%s %d\n" $f $(size -A -d $f | grep BTF | awk '{print $2}'); done | sort -nr -k2 | head -n10
./drivers/gpu/drm/i915/i915.ko 570570
./drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.ko 520240
./drivers/gpu/drm/radeon/radeon.ko 503849
./drivers/infiniband/hw/mlx5/mlx5_ib.ko 491777
./fs/xfs/xfs.ko 411544
./drivers/net/ethernet/intel/i40e/i40e.ko 403904
./drivers/net/ethernet/broadcom/bnx2x/bnx2x.ko 398754
./drivers/infiniband/core/ib_core.ko 397224
./fs/cifs/cifs.ko 386249
./fs/nfsd/nfsd.ko 379738
SPLIT BTF
=========
$ for f in $(find . -name '*.ko'); do size -A -d $f | grep BTF | awk '{print $2}'; done | awk '{ s += $1 } END { print s }'
5194047
$ for f in $(find . -name '*.ko'); do printf "%s %d\n" $f $(size -A -d $f | grep BTF | awk '{print $2}'); done | sort -nr -k2 | head -n10
./drivers/gpu/drm/i915/i915.ko 293206
./drivers/gpu/drm/radeon/radeon.ko 282103
./fs/xfs/xfs.ko 222150
./drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.ko 198503
./drivers/infiniband/hw/mlx5/mlx5_ib.ko 198356
./drivers/net/ethernet/broadcom/bnx2x/bnx2x.ko 113444
./fs/cifs/cifs.ko 109379
./arch/x86/kvm/kvm.ko 100225
./drivers/gpu/drm/drm.ko 94827
./drivers/infiniband/core/ib_core.ko 91188
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201110011932.3201430-4-andrii@kernel.org
Remote KCOV coverage collection enables coverage-guided fuzzing of the
code that is not reachable during normal system call execution. It is
especially helpful for fuzzing networking subsystems, where it is
common to perform packet handling in separate work queues even for the
packets that originated directly from the user space.
Enable coverage-guided frame injection by adding kcov remote handle to
skb extensions. Default initialization in __alloc_skb and
__build_skb_around ensures that no socket buffer that was generated
during a system call will be missed.
Code that is of interest and that performs packet processing should be
annotated with kcov_remote_start()/kcov_remote_stop().
An alternative approach is to determine kcov_handle solely on the
basis of the device/interface that received the specific socket
buffer. However, in this case it would be impossible to distinguish
between packets that originated during normal background network
processes or were intentionally injected from the user space.
Signed-off-by: Aleksandr Nogikh <nogikh@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The files under Documentation/ABI should follow the syntax
as defined at Documentation/ABI/README.
Allow checking if they're following the syntax by running
the ABI parser script on COMPILE_TEST.
With that, when there's a problem with a file under
Documentation/ABI, it would produce a warning like:
Warning: file ./Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats#14:
What '/sys/bus/pci/devices/<dev>/aer_stats/aer_rootport_total_err_cor' doesn't have a description
Warning: file ./Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats#21:
What '/sys/bus/pci/devices/<dev>/aer_stats/aer_rootport_total_err_fatal' doesn't have a description
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/57a38de85cb4b548857207cf1fc1bf1ee08613c9.1604042072.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- Support 'make compile_commands.json' to generate the compilation
database more easily, avoiding stale entries
- Support 'make clang-analyzer' and 'make clang-tidy' for static checks
using clang-tidy
- Preprocess scripts/modules.lds.S to allow CONFIG options in the module
linker script
- Drop cc-option tests from compiler flags supported by our minimal
GCC/Clang versions
- Use always 12-digits commit hash for CONFIG_LOCALVERSION_AUTO=y
- Use sha1 build id for both BFD linker and LLD
- Improve deb-pkg for reproducible builds and rootless builds
- Remove stale, useless scripts/namespace.pl
- Turn -Wreturn-type warning into error
- Fix build error of deb-pkg when CONFIG_MODULES=n
- Replace 'hostname' command with more portable 'uname -n'
- Various Makefile cleanups
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Merge tag 'kbuild-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Support 'make compile_commands.json' to generate the compilation
database more easily, avoiding stale entries
- Support 'make clang-analyzer' and 'make clang-tidy' for static checks
using clang-tidy
- Preprocess scripts/modules.lds.S to allow CONFIG options in the
module linker script
- Drop cc-option tests from compiler flags supported by our minimal
GCC/Clang versions
- Use always 12-digits commit hash for CONFIG_LOCALVERSION_AUTO=y
- Use sha1 build id for both BFD linker and LLD
- Improve deb-pkg for reproducible builds and rootless builds
- Remove stale, useless scripts/namespace.pl
- Turn -Wreturn-type warning into error
- Fix build error of deb-pkg when CONFIG_MODULES=n
- Replace 'hostname' command with more portable 'uname -n'
- Various Makefile cleanups
* tag 'kbuild-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
kbuild: Use uname for LINUX_COMPILE_HOST detection
kbuild: Only add -fno-var-tracking-assignments for old GCC versions
kbuild: remove leftover comment for filechk utility
treewide: remove DISABLE_LTO
kbuild: deb-pkg: clean up package name variables
kbuild: deb-pkg: do not build linux-headers package if CONFIG_MODULES=n
kbuild: enforce -Werror=return-type
scripts: remove namespace.pl
builddeb: Add support for all required debian/rules targets
builddeb: Enable rootless builds
builddeb: Pass -n to gzip for reproducible packages
kbuild: split the build log of kallsyms
kbuild: explicitly specify the build id style
scripts/setlocalversion: make git describe output more reliable
kbuild: remove cc-option test of -Werror=date-time
kbuild: remove cc-option test of -fno-stack-check
kbuild: remove cc-option test of -fno-strict-overflow
kbuild: move CFLAGS_{KASAN,UBSAN,KCSAN} exports to relevant Makefiles
kbuild: remove redundant CONFIG_KASAN check from scripts/Makefile.kasan
kbuild: do not create built-in objects for external module builds
...
This Kunit update for Linux 5.10-rc1 consists of:
- add Kunit to kernel_init() and remove KUnit from init calls entirely.
This addresses the concern Kunit would not work correctly during
late init phase.
- add a linker section where KUnit can put references to its test suites.
This patch is the first step in transitioning to dispatching all KUnit
tests from a centralized executor rather than having each as its own
separate late_initcall.
- add a centralized executor to dispatch tests rather than relying on
late_initcall to schedule each test suite separately. Centralized
execution is for built-in tests only; modules will execute tests when
loaded.
- convert bitfield test to use KUnit framework
- Documentation updates for naming guidelines and how kunit_test_suite()
works.
- add test plan to KUnit TAP format
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Merge tag 'linux-kselftest-kunit-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull more Kunit updates from Shuah Khan:
- add Kunit to kernel_init() and remove KUnit from init calls entirely.
This addresses the concern that Kunit would not work correctly during
late init phase.
- add a linker section where KUnit can put references to its test
suites.
This is the first step in transitioning to dispatching all KUnit
tests from a centralized executor rather than having each as its own
separate late_initcall.
- add a centralized executor to dispatch tests rather than relying on
late_initcall to schedule each test suite separately. Centralized
execution is for built-in tests only; modules will execute tests when
loaded.
- convert bitfield test to use KUnit framework
- Documentation updates for naming guidelines and how
kunit_test_suite() works.
- add test plan to KUnit TAP format
* tag 'linux-kselftest-kunit-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
lib: kunit: Fix compilation test when using TEST_BIT_FIELD_COMPILE
lib: kunit: add bitfield test conversion to KUnit
Documentation: kunit: add a brief blurb about kunit_test_suite
kunit: test: add test plan to KUnit TAP format
init: main: add KUnit to kernel init
kunit: test: create a single centralized executor for all tests
vmlinux.lds.h: add linker section for KUnit test suites
Documentation: kunit: Add naming guidelines
Pull RCU changes from Ingo Molnar:
- Debugging for smp_call_function()
- RT raw/non-raw lock ordering fixes
- Strict grace periods for KASAN
- New smp_call_function() torture test
- Torture-test updates
- Documentation updates
- Miscellaneous fixes
[ This doesn't actually pull the tag - I've dropped the last merge from
the RCU branch due to questions about the series. - Linus ]
* tag 'core-rcu-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (77 commits)
smp: Make symbol 'csd_bug_count' static
kernel/smp: Provide CSD lock timeout diagnostics
smp: Add source and destination CPUs to __call_single_data
rcu: Shrink each possible cpu krcp
rcu/segcblist: Prevent useless GP start if no CBs to accelerate
torture: Add gdb support
rcutorture: Allow pointer leaks to test diagnostic code
rcutorture: Hoist OOM registry up one level
refperf: Avoid null pointer dereference when buf fails to allocate
rcutorture: Properly synchronize with OOM notifier
rcutorture: Properly set rcu_fwds for OOM handling
torture: Add kvm.sh --help and update help message
rcutorture: Add CONFIG_PROVE_RCU_LIST to TREE05
torture: Update initrd documentation
rcutorture: Replace HTTP links with HTTPS ones
locktorture: Make function torture_percpu_rwsem_init() static
torture: document --allcpus argument added to the kvm.sh script
rcutorture: Output number of elapsed grace periods
rcutorture: Remove KCSAN stubs
rcu: Remove unused "cpu" parameter from rcu_report_qs_rdp()
...
Patch series "add fault injection to user memory access", v3.
The goal of this series is to improve testing of fault-tolerance in usages
of user memory access functions, by adding support for fault injection.
syzkaller/syzbot are using the existing fault injection modes and will use
this particular feature also.
The first patch adds failure injection capability for usercopy functions.
The second changes usercopy functions to use this new failure capability
(copy_from_user, ...). The third patch adds get/put/clear_user failures
to x86.
This patch (of 3):
Add a failure injection capability to improve testing of fault-tolerance
in usages of user memory access functions.
Add CONFIG_FAULT_INJECTION_USERCOPY to enable faults in usercopy
functions. The should_fail_usercopy function is to be called by these
functions (copy_from_user, get_user, ...) in order to fail or not.
Signed-off-by: Albert van der Linde <alinde@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20200831171733.955393-1-alinde@google.com
Link: http://lkml.kernel.org/r/20200831171733.955393-2-alinde@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Here is a very rare race which leaks memory:
Page P0 is allocated to the page cache. Page P1 is free.
Thread A Thread B Thread C
find_get_entry():
xas_load() returns P0
Removes P0 from page cache
P0 finds its buddy P1
alloc_pages(GFP_KERNEL, 1) returns P0
P0 has refcount 1
page_cache_get_speculative(P0)
P0 has refcount 2
__free_pages(P0)
P0 has refcount 1
put_page(P0)
P1 is not freed
Fix this by freeing all the pages in __free_pages() that won't be freed
by the call to put_page(). It's usually not a good idea to split a page,
but this is a very unlikely scenario.
Fixes: e286781d5f ("mm: speculative page references")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200926213919.26642-1-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds the conversion of the runtime tests of test_bitfield,
from `lib/test_bitfield.c` to KUnit tests.
Code Style Documentation: [0]
Signed-off-by: Vitor Massaru Iha <vitor@massaru.org>
Link: [0] https://lore.kernel.org/linux-kselftest/20200620054944.167330-1-davidgow@google.com/T/#u
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
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>
This moves the KCSAN kconfig items under menu 'Generic Kernel Debugging
Instruments' where UBSAN resides.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200904152224.5570-1-changbin.du@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit causes csd_lock_wait() to emit diagnostics when a CPU
fails to respond quickly enough to one of the smp_call_function()
family of function calls. These diagnostics are enabled by a new
CSD_LOCK_WAIT_DEBUG Kconfig option that depends on DEBUG_KERNEL.
This commit was inspired by an earlier patch by Josef Bacik.
[ paulmck: Fix for syzbot+0f719294463916a3fc0e@syzkaller.appspotmail.com ]
[ paulmck: Fix KASAN use-after-free issue reported by Qian Cai. ]
[ paulmck: Fix botched nr_cpu_ids comparison per Dan Carpenter. ]
[ paulmck: Apply Peter Zijlstra feedback. ]
Link: https://lore.kernel.org/lkml/00000000000042f21905a991ecea@google.com
Link: https://lore.kernel.org/lkml/0000000000002ef21705a9933cf3@google.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
While playing with [1] I saw that the handling
of CONFIG_DEBUG_INFO can be simplified.
[1] https://patchwork.kernel.org/patch/11716107/
Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This commit adds an smp_call_function() torture test that repeatedly
invokes this function and complains if things go badly awry.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
There exists duplicated "the" in the help text of CONFIG_PANIC_TIMEOUT,
Remove it.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Xuefeng Li <lixuefeng@loongson.cn>
Link: http://lkml.kernel.org/r/1591103358-32087-2-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Coly Li <colyli@suse.de> [crc64.c]
Link: http://lkml.kernel.org/r/20200726112154.16510-1-grandmaster@al2klimov.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since test_lockup is a test module to generate lockups, it is better to
limit TEST_LOCKUP to module (=m) or disabled (=n) because we can not use
the module parameters when CONFIG_TEST_LOCKUP=y.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/1595555407-29875-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Recently 0day reported many strange performance changes (regression or
improvement), in which there was no obvious relation between the culprit
commit and the benchmark at the first look, and it causes people to doubt
the test itself is wrong.
Upon further check, many of these cases are caused by the change to the
alignment of kernel text or data, as whole text/data of kernel are linked
together, change in one domain may affect alignments of other domains.
gcc has an option '-falign-functions=n' to force text aligned, and with
that option enabled, some of those performance changes will be gone, like
[1][2][3].
Add this option so that developers and 0day can easily find performance
bump caused by text alignment change, as tracking these strange bump is
quite time consuming. Though it can't help in other cases like data
alignment changes like [4].
Following is some size data for v5.7 kernel built with a RHEL config used
in 0day:
text data bss dec filename
19738771 13292906 5554236 38585913 vmlinux.noalign
19758591 13297002 5529660 38585253 vmlinux.align32
Raw vmlinux size in bytes:
v5.7 v5.7+align32
253950832 254018000 +0.02%
Some benchmark data, most of them have no big change:
* hackbench: [ -1.8%, +0.5%]
* fsmark: [ -3.2%, +3.4%] # ext4/xfs/btrfs
* kbuild: [ -2.0%, +0.9%]
* will-it-scale: [ -0.5%, +1.8%] # mmap1/pagefault3
* netperf:
- TCP_CRR [+16.6%, +97.4%]
- TCP_RR [-18.5%, -1.8%]
- TCP_STREAM [ -1.1%, +1.9%]
[1] https://lore.kernel.org/lkml/20200114085637.GA29297@shao2-debian/
[2] https://lore.kernel.org/lkml/20200330011254.GA14393@feng-iot/
[3] https://lore.kernel.org/lkml/1d98d1f0-fe84-6df7-f5bd-f4cb2cdb7f45@intel.com/
[4] https://lore.kernel.org/lkml/20200205123216.GO12867@shao2-debian/
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@intel.com>
Link: http://lkml.kernel.org/r/1595475001-90945-1-git-send-email-feng.tang@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Here is the "big" set of changes to the driver core, and some drivers
using the changes, for 5.9-rc1.
"Biggest" thing in here is the device link exposure in sysfs, to help
to tame the madness that is SoC device tree representations and driver
interactions with it.
Other stuff in here that is interesting is:
- device probe log helper so that drivers can report problems in
a unified way easier.
- devres functions added
- DEVICE_ATTR_ADMIN_* macro added to make it harder to write
incorrect sysfs file permissions
- documentation cleanups
- ability for debugfs to be present in the kernel, yet not
exposed to userspace. Needed for systems that want it
enabled, but do not trust users, so they can still use some
kernel functions that were otherwise disabled.
- other minor fixes and cleanups
The patches outside of drivers/base/ all have acks from the respective
subsystem maintainers to go through this tree instead of theirs.
All of these have been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the "big" set of changes to the driver core, and some drivers
using the changes, for 5.9-rc1.
"Biggest" thing in here is the device link exposure in sysfs, to help
to tame the madness that is SoC device tree representations and driver
interactions with it.
Other stuff in here that is interesting is:
- device probe log helper so that drivers can report problems in a
unified way easier.
- devres functions added
- DEVICE_ATTR_ADMIN_* macro added to make it harder to write
incorrect sysfs file permissions
- documentation cleanups
- ability for debugfs to be present in the kernel, yet not exposed to
userspace. Needed for systems that want it enabled, but do not
trust users, so they can still use some kernel functions that were
otherwise disabled.
- other minor fixes and cleanups
The patches outside of drivers/base/ all have acks from the respective
subsystem maintainers to go through this tree instead of theirs.
All of these have been in linux-next with no reported issues"
* tag 'driver-core-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (39 commits)
drm/bridge: lvds-codec: simplify error handling
drm/bridge/sii8620: fix resource acquisition error handling
driver core: add deferring probe reason to devices_deferred property
driver core: add device probe log helper
driver core: Avoid binding drivers to dead devices
Revert "test_firmware: Test platform fw loading on non-EFI systems"
firmware_loader: EFI firmware loader must handle pre-allocated buffer
selftest/firmware: Add selftest timeout in settings
test_firmware: Test platform fw loading on non-EFI systems
driver core: Change delimiter in devlink device's name to "--"
debugfs: Add access restriction option
tracefs: Remove unnecessary debug_fs checks.
driver core: Fix probe_count imbalance in really_probe()
kobject: remove unused KOBJ_MAX action
driver core: Fix sleeping in invalid context during device link deletion
driver core: Add waiting_for_supplier sysfs file for devices
driver core: Add state_synced sysfs file for devices that support it
driver core: Expose device link details in sysfs
driver core: Drop mention of obsolete bus rwsem from kernel-doc
debugfs: file: Remove unnecessary cast in kfree()
...
Asserting that preemption is enabled or disabled is a critical sanity
check. Developers are usually reluctant to add such a check in a
fastpath as reading the preemption count can be costly.
Extend the lockdep API with macros asserting that preemption is disabled
or enabled. If lockdep is disabled, or if the underlying architecture
does not support kernel preemption, this assert has no runtime overhead.
References: f54bb2ec02 ("locking/lockdep: Add IRQs disabled/enabled assertion APIs: ...")
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200720155530.1173732-8-a.darwish@linutronix.de
Prior to commit:
859d069ee1 ("lockdep: Prepare for NMI IRQ state tracking")
IRQ state tracking was disabled in NMIs due to nmi_enter()
doing lockdep_off() -- with the obvious requirement that NMI entry
call nmi_enter() before trace_hardirqs_off().
[ AFAICT, PowerPC and SH violate this order on their NMI entry ]
However, that commit explicitly changed lockdep_hardirqs_*() to ignore
lockdep_off() and breaks every architecture that has irq-tracing in
it's NMI entry that hasn't been fixed up (x86 being the only fixed one
at this point).
The reason for this change is that by ignoring lockdep_off() we can:
- get rid of 'current->lockdep_recursion' in lockdep_assert_irqs*()
which was going to to give header-recursion issues with the
seqlock rework.
- allow these lockdep_assert_*() macros to function in NMI context.
Restore the previous state of things and allow an architecture to
opt-in to the NMI IRQ tracking support, however instead of relying on
lockdep_off(), rely on in_nmi(), both are part of nmi_enter() and so
over-all entry ordering doesn't need to change.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200727124852.GK119549@hirez.programming.kicks-ass.net
Since debugfs include sensitive information it need to be treated
carefully. But it also has many very useful debug functions for userspace.
With this option we can have same configuration for system with
need of debugfs and a way to turn it off. This gives a extra protection
for exposure on systems where user-space services with system
access are attacked.
It is controlled by a configurable default value that can be override
with a kernel command line parameter. (debugfs=)
It can be on or off, but also internally on but not seen from user-space.
This no-mount mode do not register a debugfs as filesystem, but client can
register their parts in the internal structures. This data can be readed
with a debugger or saved with a crashkernel. When it is off clients
get EPERM error when accessing the functions for registering their
components.
Signed-off-by: Peter Enderborg <peter.enderborg@sony.com>
Link: https://lore.kernel.org/r/20200716071511.26864-3-peter.enderborg@sony.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a selftest for the usage of FPU code in kernel mode.
Currently only implemented for x86. In the future, kernel FPU testing
could be unified between the different architectures supporting it.
[ bp:
- Split out from a conglomerate patch, put comments over statements.
- run the test only on debugfs write.
- Add bare-minimum run_test_fpu.sh, run 1000 iterations on all CPUs
by default.
- Add conditionally -msse2 so that clang doesn't generate library
calls.
- Use cc-option to detect gcc 7.1 not supporting -mpreferred-stack-boundary=3 (amluto).
- Document stuff so that we don't forget.
- Fix:
ld: lib/test_fpu.o: in function `test_fpu_get':
>> test_fpu.c:(.text+0x16e): undefined reference to `__sanitizer_cov_trace_cmpd'
>> ld: test_fpu.c:(.text+0x1a7): undefined reference to `__sanitizer_cov_trace_cmpd'
ld: test_fpu.c:(.text+0x1e0): undefined reference to `__sanitizer_cov_trace_cmpd'
]
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Petteri Aimonen <jpa@git.mail.kapsi.fi>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lkml.kernel.org/r/20200624114646.28953-3-bp@alien8.de
cc-option and as-option are almost the same; both pass the flag to
$(CC). The main difference is the cc-option stops before the assemble
stage (-S option) whereas as-option stops after (-c option).
I chose -S because it is slightly faster, but $(cc-option,-gz=zlib)
returns a wrong result (https://lkml.org/lkml/2020/6/9/1529).
It has been fixed by commit 7b16994437 ("Makefile: Improve compressed
debug info support detection"), but the assembler should always be
invoked for more reliable compiler option tests.
However, you cannot simply replace -S with -c because the following
code in lib/Kconfig.debug would break:
depends on $(cc-option,-gsplit-dwarf)
The combination of -c and -gsplit-dwarf does not accept /dev/null as
output.
$ cat /dev/null | gcc -gsplit-dwarf -S -x c - -o /dev/null
$ echo $?
0
$ cat /dev/null | gcc -gsplit-dwarf -c -x c - -o /dev/null
objcopy: Warning: '/dev/null' is not an ordinary file
$ echo $?
1
$ cat /dev/null | gcc -gsplit-dwarf -c -x c - -o tmp.o
$ echo $?
0
There is another flag that creates an separate file based on the
object file path:
$ cat /dev/null | gcc -ftest-coverage -c -x c - -o /dev/null
<stdin>:1: error: cannot open /dev/null.gcno
So, we cannot use /dev/null to sink the output.
Align the cc-option implementation with scripts/Kbuild.include.
With -c option used in cc-option, as-option is unneeded.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Commit
10e68b02c8 ("Makefile: support compressed debug info")
added support for compressed debug sections.
Support is detected by checking
- does the compiler support -gz=zlib
- does the assembler support --compressed-debug-sections=zlib
- does the linker support --compressed-debug-sections=zlib
However, the gcc driver's support for this option is somewhat
convoluted. The driver's builtin specs are set based on the version of
binutils that it was configured with. It reports an error if the
configure-time linker/assembler (i.e., not necessarily the actual
assembler that will be run) do not support the option, but only if the
assembler (or linker) is actually invoked when -gz=zlib is passed.
The cc-option check in scripts/Kconfig.include does not invoke the
assembler, so the gcc driver reports success even if it does not support
the option being passed to the assembler.
Because the as-option check passes the option directly to the assembler
via -Wa,--compressed-debug-sections=zlib, the gcc driver does not see
this option and will never report an error.
Combined with an installed version of binutils that is more recent than
the one the compiler was built with, it is possible for all three tests
to succeed, yet an actual compilation with -gz=zlib to fail.
Moreover, it is unnecessary to explicitly pass
--compressed-debug-sections=zlib to the assembler via -Wa, since the
driver will do that automatically when it supports -gz=zlib.
Convert the as-option to just -gz=zlib, simplifying it as well as
performing a better test of the gcc driver's capabilities.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
- fix build rules in binderfs sample
- fix build errors when Kbuild recurses to the top Makefile
- covert '---help---' in Kconfig to 'help'
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Merge tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:
- fix build rules in binderfs sample
- fix build errors when Kbuild recurses to the top Makefile
- covert '---help---' in Kconfig to 'help'
* tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
treewide: replace '---help---' in Kconfig files with 'help'
kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables
samples: binderfs: really compile this sample and fix build issues
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.
This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.
There are a variety of indentation styles found.
a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'
In order to convert all of them to 1 tab + 'help', I ran the
following commend:
$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
KCSAN is a dynamic race detector, which relies on compile-time
instrumentation, and uses a watchpoint-based sampling approach to detect
races.
The feature was under development for quite some time and has already found
legitimate bugs.
Unfortunately it comes with a limitation, which was only understood late in
the development cycle:
It requires an up to date CLANG-11 compiler
CLANG-11 is not yet released (scheduled for June), but it's the only
compiler today which handles the kernel requirements and especially the
annotations of functions to exclude them from KCSAN instrumentation
correctly.
These annotations really need to work so that low level entry code and
especially int3 text poke handling can be completely isolated.
A detailed discussion of the requirements and compiler issues can be found
here:
https://lore.kernel.org/lkml/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com/
We came to the conclusion that trying to work around compiler limitations
and bugs again would end up in a major trainwreck, so requiring a working
compiler seemed to be the best choice.
For Continous Integration purposes the compiler restriction is manageable
and that's where most xxSAN reports come from.
For a change this limitation might make GCC people actually look at their
bugs. Some issues with CSAN in GCC are 7 years old and one has been 'fixed'
3 years ago with a half baken solution which 'solved' the reported issue
but not the underlying problem.
The KCSAN developers also ponder to use a GCC plugin to become independent,
but that's not something which will show up in a few days.
Blocking KCSAN until wide spread compiler support is available is not a
really good alternative because the continuous growth of lockless
optimizations in the kernel demands proper tooling support.
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Merge tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull the Kernel Concurrency Sanitizer from Thomas Gleixner:
"The Kernel Concurrency Sanitizer (KCSAN) is a dynamic race detector,
which relies on compile-time instrumentation, and uses a
watchpoint-based sampling approach to detect races.
The feature was under development for quite some time and has already
found legitimate bugs.
Unfortunately it comes with a limitation, which was only understood
late in the development cycle:
It requires an up to date CLANG-11 compiler
CLANG-11 is not yet released (scheduled for June), but it's the only
compiler today which handles the kernel requirements and especially
the annotations of functions to exclude them from KCSAN
instrumentation correctly.
These annotations really need to work so that low level entry code and
especially int3 text poke handling can be completely isolated.
A detailed discussion of the requirements and compiler issues can be
found here:
https://lore.kernel.org/lkml/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com/
We came to the conclusion that trying to work around compiler
limitations and bugs again would end up in a major trainwreck, so
requiring a working compiler seemed to be the best choice.
For Continous Integration purposes the compiler restriction is
manageable and that's where most xxSAN reports come from.
For a change this limitation might make GCC people actually look at
their bugs. Some issues with CSAN in GCC are 7 years old and one has
been 'fixed' 3 years ago with a half baken solution which 'solved' the
reported issue but not the underlying problem.
The KCSAN developers also ponder to use a GCC plugin to become
independent, but that's not something which will show up in a few
days.
Blocking KCSAN until wide spread compiler support is available is not
a really good alternative because the continuous growth of lockless
optimizations in the kernel demands proper tooling support"
* tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (76 commits)
compiler_types.h, kasan: Use __SANITIZE_ADDRESS__ instead of CONFIG_KASAN to decide inlining
compiler.h: Move function attributes to compiler_types.h
compiler.h: Avoid nested statement expression in data_race()
compiler.h: Remove data_race() and unnecessary checks from {READ,WRITE}_ONCE()
kcsan: Update Documentation to change supported compilers
kcsan: Remove 'noinline' from __no_kcsan_or_inline
kcsan: Pass option tsan-instrument-read-before-write to Clang
kcsan: Support distinguishing volatile accesses
kcsan: Restrict supported compilers
kcsan: Avoid inserting __tsan_func_entry/exit if possible
ubsan, kcsan: Don't combine sanitizer with kcov on clang
objtool, kcsan: Add kcsan_disable_current() and kcsan_enable_current_nowarn()
kcsan: Add __kcsan_{enable,disable}_current() variants
checkpatch: Warn about data_race() without comment
kcsan: Use GFP_ATOMIC under spin lock
Improve KCSAN documentation a bit
kcsan: Make reporting aware of KCSAN tests
kcsan: Fix function matching in report
kcsan: Change data_race() to no longer require marking racing accesses
kcsan: Move kcsan_{disable,enable}_current() to kcsan-checks.h
...
Merge the state of the locking kcsan branch before the read/write_once()
and the atomics modifications got merged.
Squash the fallout of the rebase on top of the read/write once and atomic
fallback work into the merge. The history of the original branch is
preserved in tag locking-kcsan-2020-06-02.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Linus Torvalds