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2020-06-15kcsan: Remove __no_kcsan_or_inlinePeter Zijlstra1-6/+0
There are no more user of this function attribute, also, with us now actively supporting '__no_kcsan inline' it doesn't make sense to have in any case. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2020-06-11kcsan: Update Documentation to change supported compilersMarco Elver1-8/+1
Document change in required compiler version for KCSAN, and remove the now redundant note about __no_kcsan and inlining problems with older compilers. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/20200521142047.169334-8-elver@google.com
2020-06-11Rebase locking/kcsan to locking/urgentThomas Gleixner2-0/+329
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>
2020-06-11Merge tag 'docs-5.8-2' of git://git.lwn.net/linuxLinus Torvalds2-5/+5
Pull more documentation updates from Jonathan Corbet: "A handful of late-arriving docs fixes, along with a patch changing a lot of HTTP links to HTTPS that had to be yanked and redone before the first pull" * tag 'docs-5.8-2' of git://git.lwn.net/linux: docs/memory-barriers.txt/kokr: smp_mb__{before,after}_atomic(): update Documentation Documentation: devres: add missing entry for devm_platform_get_and_ioremap_resource() Replace HTTP links with HTTPS ones: documentation docs: it_IT: address invalid reference warnings doc: zh_CN: use doc reference to resolve undefined label warning docs: Update the location of the LF NDA program docs: dev-tools: coccinelle: underlines
2020-06-09Merge tag 'linux-kselftest-kunit-5.8-rc1' of ↵Linus Torvalds2-7/+10
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull Kunit updates from Shuah Khan: "This consists of: - Several config fragment fixes from Anders Roxell to improve test coverage. - Improvements to kunit run script to use defconfig as default and restructure the code for config/build/exec/parse from Vitor Massaru Iha and David Gow. - Miscellaneous documentation warn fix" * tag 'linux-kselftest-kunit-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: security: apparmor: default KUNIT_* fragments to KUNIT_ALL_TESTS fs: ext4: default KUNIT_* fragments to KUNIT_ALL_TESTS drivers: base: default KUNIT_* fragments to KUNIT_ALL_TESTS lib: Kconfig.debug: default KUNIT_* fragments to KUNIT_ALL_TESTS kunit: default KUNIT_* fragments to KUNIT_ALL_TESTS kunit: Kconfig: enable a KUNIT_ALL_TESTS fragment kunit: Fix TabError, remove defconfig code and handle when there is no kunitconfig kunit: use KUnit defconfig by default kunit: use --build_dir=.kunit as default Documentation: test.h - fix warnings kunit: kunit_tool: Separate out config/build/exec/parse
2020-06-09Merge tag 'linux-kselftest-5.8-rc1' of ↵Linus Torvalds1-0/+23
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kselftest updates from Shuah Khan: "This consists of: - Several fixes from Masami Hiramatsu to improve coverage for lib and sysctl tests. - Clean up to vdso test and a new test for getcpu() from Mark Brown. - Add new gen_tar selftests Makefile target generate selftest package running "make gen_tar" in selftests directory from Veronika Kabatova. - Other miscellaneous fixes to timens, exec, tpm2 tests" * tag 'linux-kselftest-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: selftests/sysctl: Make sysctl test driver as a module selftests/sysctl: Fix to load test_sysctl module lib: Make test_sysctl initialized as module lib: Make prime number generator independently selectable selftests/ftrace: Return unsupported if no error_log file selftests/ftrace: Use printf for backslash included command selftests/timens: handle a case when alarm clocks are not supported Kernel selftests: Add check if TPM devices are supported selftests: vdso: Add a selftest for vDSO getcpu() selftests: vdso: Use a header file to prototype parse_vdso API selftests: vdso: Rename vdso_test to vdso_test_gettimeofday selftests/exec: Verify execve of non-regular files fail selftests: introduce gen_tar Makefile target
2020-06-08Replace HTTP links with HTTPS ones: documentationAlexander A. Klimov1-1/+1
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de> Link: https://lore.kernel.org/r/20200526060544.25127-1-grandmaster@al2klimov.de Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-06-08docs: dev-tools: coccinelle: underlinesHeinrich Schuchardt1-4/+4
Underline lengths should match the lengths of headings to avoid build warnings with Sphinx. Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Acked-by: Julia Lawall <julia.lawall@inria.fr> Link: https://lore.kernel.org/r/20200605030405.6479-1-xypron.glpk@gmx.de Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-06-05kcov: collect coverage from interruptsAndrey Konovalov1-8/+9
This change extends kcov remote coverage support to allow collecting coverage from soft interrupts in addition to kernel background threads. To collect coverage from code that is executed in softirq context, a part of that code has to be annotated with kcov_remote_start/stop() in a similar way as how it is done for global kernel background threads. Then the handle used for the annotations has to be passed to the KCOV_REMOTE_ENABLE ioctl. Internally this patch adjusts the __sanitizer_cov_trace_pc() compiler inserted callback to not bail out when called from softirq context. kcov_remote_start/stop() are updated to save/restore the current per task kcov state in a per-cpu area (in case the softirq came when the kernel was already collecting coverage in task context). Coverage from softirqs is collected into pre-allocated per-cpu areas, whose size is controlled by the new CONFIG_KCOV_IRQ_AREA_SIZE. [andreyknvl@google.com: turn current->kcov_softirq into unsigned int to fix objtool warning] Link: http://lkml.kernel.org/r/841c778aa3849c5cb8c3761f56b87ce653a88671.1585233617.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Marco Elver <elver@google.com> Link: http://lkml.kernel.org/r/469bd385c431d050bc38a593296eff4baae50666.1584655448.git.andreyknvl@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds1-1/+2
Pull networking updates from David Miller: 1) Allow setting bluetooth L2CAP modes via socket option, from Luiz Augusto von Dentz. 2) Add GSO partial support to igc, from Sasha Neftin. 3) Several cleanups and improvements to r8169 from Heiner Kallweit. 4) Add IF_OPER_TESTING link state and use it when ethtool triggers a device self-test. From Andrew Lunn. 5) Start moving away from custom driver versions, use the globally defined kernel version instead, from Leon Romanovsky. 6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin. 7) Allow hard IRQ deferral during NAPI, from Eric Dumazet. 8) Add sriov and vf support to hinic, from Luo bin. 9) Support Media Redundancy Protocol (MRP) in the bridging code, from Horatiu Vultur. 10) Support netmap in the nft_nat code, from Pablo Neira Ayuso. 11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina Dubroca. Also add ipv6 support for espintcp. 12) Lots of ReST conversions of the networking documentation, from Mauro Carvalho Chehab. 13) Support configuration of ethtool rxnfc flows in bcmgenet driver, from Doug Berger. 14) Allow to dump cgroup id and filter by it in inet_diag code, from Dmitry Yakunin. 15) Add infrastructure to export netlink attribute policies to userspace, from Johannes Berg. 16) Several optimizations to sch_fq scheduler, from Eric Dumazet. 17) Fallback to the default qdisc if qdisc init fails because otherwise a packet scheduler init failure will make a device inoperative. From Jesper Dangaard Brouer. 18) Several RISCV bpf jit optimizations, from Luke Nelson. 19) Correct the return type of the ->ndo_start_xmit() method in several drivers, it's netdev_tx_t but many drivers were using 'int'. From Yunjian Wang. 20) Add an ethtool interface for PHY master/slave config, from Oleksij Rempel. 21) Add BPF iterators, from Yonghang Song. 22) Add cable test infrastructure, including ethool interfaces, from Andrew Lunn. Marvell PHY driver is the first to support this facility. 23) Remove zero-length arrays all over, from Gustavo A. R. Silva. 24) Calculate and maintain an explicit frame size in XDP, from Jesper Dangaard Brouer. 25) Add CAP_BPF, from Alexei Starovoitov. 26) Support terse dumps in the packet scheduler, from Vlad Buslov. 27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei. 28) Add devm_register_netdev(), from Bartosz Golaszewski. 29) Minimize qdisc resets, from Cong Wang. 30) Get rid of kernel_getsockopt and kernel_setsockopt in order to eliminate set_fs/get_fs calls. From Christoph Hellwig. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits) selftests: net: ip_defrag: ignore EPERM net_failover: fixed rollback in net_failover_open() Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv" Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv" vmxnet3: allow rx flow hash ops only when rss is enabled hinic: add set_channels ethtool_ops support selftests/bpf: Add a default $(CXX) value tools/bpf: Don't use $(COMPILE.c) bpf, selftests: Use bpf_probe_read_kernel s390/bpf: Use bcr 0,%0 as tail call nop filler s390/bpf: Maintain 8-byte stack alignment selftests/bpf: Fix verifier test selftests/bpf: Fix sample_cnt shared between two threads bpf, selftests: Adapt cls_redirect to call csum_level helper bpf: Add csum_level helper for fixing up csum levels bpf: Fix up bpf_skb_adjust_room helper's skb csum setting sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf() crypto/chtls: IPv6 support for inline TLS Crypto/chcr: Fixes a coccinile check error Crypto/chcr: Fixes compilations warnings ...
2020-06-02Documentation: kgdboc: Document new kgdboc_earlycon parameterDouglas Anderson1-0/+24
The recent patch ("kgdboc: Add kgdboc_earlycon to support early kgdb using boot consoles") adds a new kernel command line parameter. Document it. Note that the patch adding the feature does some comparing/contrasting of "kgdboc_earlycon" vs. the existing "ekgdboc". See that patch for more details, but briefly "ekgdboc" can be used _instead_ of "kgdboc" and just makes "kgdboc" do its normal initialization early (only works if your tty driver is already ready). The new "kgdboc_earlycon" works in combination with "kgdboc" and is backed by boot consoles. Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Link: https://lore.kernel.org/r/20200507130644.v4.9.I7d5eb42c6180c831d47aef1af44d0b8be3fac559@changeid Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-05-22Documentation: test.h - fix warningsLothar Rubusch2-7/+10
Fix warnings at 'make htmldocs', and formatting issues in the resulting documentation. - test.h: Fix annotation in kernel-doc parameter description. - Documentation/*.rst: Fixing formatting issues, and a duplicate label issue due to usage of sphinx.ext.autosectionlabel and identical labels within one document (sphinx warning) Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-05-20selftests: introduce gen_tar Makefile targetVeronika Kabatova1-0/+23
The gen_kselftest_tar.sh always packages *all* selftests and doesn't pass along any variables to `make install` to influence what should be built. This can result in an early error on the command line ("Unknown tarball format TARGETS=XXX"), or unexpected test failures as the tarball contains tests people wanted to skip on purpose. Since the makefile already contains all the logic, we can add a target for packaging. Keep the default .gz target the script uses, and actually extend the supported formats by using tar's autodetection. To not break current workflows, keep the gen_kselftest_tar.sh script as it is, with an added suggestion to use the makefile target instead. Signed-off-by: Veronika Kabatova <vkabatov@redhat.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-05-08Merge branch 'kcsan-for-tip' of ↵Thomas Gleixner1-83/+145
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/kcsan Pull KCSAN updates from Paul McKenney.
2020-04-28kselftest: add fixture variantsJakub Kicinski1-1/+2
Allow users to build parameterized variants of fixtures. If fixtures want variants, they call FIXTURE_VARIANT() to declare the structure to fill for each variant. Each fixture will be re-run for each of the variants defined by calling FIXTURE_VARIANT_ADD() with the differing parameters initializing the structure. Since tests are being re-run, additional initialization (steps, no_print) is also added. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-14kcsan: Introduce scoped ASSERT_EXCLUSIVE macrosMarco Elver1-1/+2
Introduce ASSERT_EXCLUSIVE_*_SCOPED(), which provide an intuitive interface to use the scoped-access feature, without having to explicitly mark the start and end of the desired scope. Basing duration of the checks on scope avoids accidental misuse and resulting false positives, which may be hard to debug. See added comments for usage. The macros are implemented using __attribute__((__cleanup__(func))), which is supported by all compilers that currently support KCSAN. Suggested-by: Boqun Feng <boqun.feng@gmail.com> Suggested-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-04-13Merge tag 'v5.7-rc1' into locking/kcsan, to resolve conflicts and refreshIngo Molnar6-30/+116
Resolve these conflicts: arch/x86/Kconfig arch/x86/kernel/Makefile Do a minor "evil merge" to move the KCSAN entry up a bit by a few lines in the Kconfig to reduce the probability of future conflicts. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-02Merge tag 'linux-kselftest-kunit-5.7-rc1' of ↵Linus Torvalds4-28/+113
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kunit updates from Shuah Khan: "This kunit update consists of: - debugfs support for displaying kunit test suite results. This is especially useful for module-loaded tests to allow disentangling of test result display from other dmesg events. CONFIG_KUNIT_DEBUGFS enables/disables the debugfs support. - Several fixes and improvements to kunit framework and tool" * tag 'linux-kselftest-kunit-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: kunit: tool: add missing test data file content kunit: update documentation to describe debugfs representation kunit: subtests should be indented 4 spaces according to TAP kunit: add log test kunit: add debugfs /sys/kernel/debug/kunit/<suite>/results display Documentation: kunit: Make the KUnit documentation less UML-specific Fix linked-list KUnit test when run multiple times kunit: kunit_tool: Allow .kunitconfig to disable config items kunit: Always print actual pointer values in asserts kunit: add --make_options kunit: Run all KUnit tests through allyesconfig kunit: kunit_parser: make parser more robust
2020-03-30Merge tag 'docs-5.7' of git://git.lwn.net/linuxLinus Torvalds2-2/+3
Pull documentation updates from Jonathan Corbet: "This has been a busy cycle for documentation work. Highlights include: - Lots of RST conversion work by Mauro, Daniel ALmeida, and others. Maybe someday we'll get to the end of this stuff...maybe... - Some organizational work to bring some order to the core-api manual. - Various new docs and additions to the existing documentation. - Typo fixes, warning fixes, ..." * tag 'docs-5.7' of git://git.lwn.net/linux: (123 commits) Documentation: x86: exception-tables: document CONFIG_BUILDTIME_TABLE_SORT MAINTAINERS: adjust to filesystem doc ReST conversion docs: deprecated.rst: Add BUG()-family doc: zh_CN: add translation for virtiofs doc: zh_CN: index files in filesystems subdirectory docs: locking: Drop :c:func: throughout docs: locking: Add 'need' to hardirq section docs: conf.py: avoid thousands of duplicate label warning on Sphinx docs: prevent warnings due to autosectionlabel docs: fix reference to core-api/namespaces.rst docs: fix pointers to io-mapping.rst and io_ordering.rst files Documentation: Better document the softlockup_panic sysctl docs: hw-vuln: tsx_async_abort.rst: get rid of an unused ref docs: perf: imx-ddr.rst: get rid of a warning docs: filesystems: fuse.rst: supress a Sphinx warning docs: translations: it: avoid duplicate refs at programming-language.rst docs: driver.rst: supress two ReSt warnings docs: trace: events.rst: convert some new stuff to ReST format Documentation: Add io_ordering.rst to driver-api manual Documentation: Add io-mapping.rst to driver-api manual ...
2020-03-26kunit: update documentation to describe debugfs representationAlan Maguire1-0/+14
Documentation should describe debugfs layout and semantics. Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Reviewed-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-03-26Documentation: kunit: Make the KUnit documentation less UML-specificDavid Gow3-28/+99
Remove some of the outmoded "Why KUnit" rationale, and move some UML-specific information to the kunit_tool page. Also update the Getting Started guide to mention running tests without the kunit_tool wrapper. Signed-off-by: David Gow <davidgow@google.com> Reviewed-by: Frank Rowand <frank.rowand@sony.com> Acked-by: Shuah Khan <skhan@linuxfoundation.org> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-03-25kcsan: Update Documentation/dev-tools/kcsan.rstMarco Elver1-83/+144
Extend and improve based on recent changes, and summarize important bits that have been missing. Tested with "make htmldocs". Signed-off-by: Marco Elver <elver@google.com> Cc: Qian Cai <cai@lca.pw> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-03-21Merge branch 'linus' into locking/kcsan, to pick up fixesIngo Molnar1-0/+1
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-21Merge branch 'x86/kdump' into locking/kcsan, to resolve conflictsIngo Molnar4-3/+23
Conflicts: arch/x86/purgatory/Makefile Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-10docs: dev-tools: kmemleak: Update list of architecturesJonathan Neuschäfer1-1/+2
* Don't list powerpc twice (once as ppc) * Drop tile, which has been removed from the source tree * Mention arm64, nds32, arc, and xtensa Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Link: https://lore.kernel.org/r/20200303194215.23756-1-j.neuschaefer@gmx.net Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-02docs: dev-tools: gcov: Remove a stray single-quoteJonathan Neuschäfer1-1/+1
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Link: https://lore.kernel.org/r/20200229173515.13868-1-j.neuschaefer@gmx.net Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-02-11Documentation: kunit: fixed sphinx error in code blockBrendan Higgins1-0/+1
Fix a missing newline in a code block that was causing a warning: Documentation/dev-tools/kunit/usage.rst:553: WARNING: Error in "code-block" directive: maximum 1 argument(s) allowed, 3 supplied. .. code-block:: bash modprobe example-test Signed-off-by: Brendan Higgins <brendanhiggins@google.com> Reviewed-by: Alan Maguire <alan.maguire@oracle.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-01-31Merge tag 'riscv-for-linus-5.6-mw0' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: "This contains a handful of patches for this merge window: - Support for kasan - 32-bit physical addresses on rv32i-based systems - Support for CONFIG_DEBUG_VIRTUAL - DT entry for the FU540 GPIO controller, which has recently had a device driver merged These boot a buildroot-based system on QEMU's virt board for me" * tag 'riscv-for-linus-5.6-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: dts: Add DT support for SiFive FU540 GPIO driver riscv: mm: add support for CONFIG_DEBUG_VIRTUAL riscv: keep 32-bit kernel to 32-bit phys_addr_t kasan: Add riscv to KASAN documentation. riscv: Add KASAN support kasan: No KASAN's memmove check if archs don't have it.
2020-01-24Merge branch 'kcsan.2020.01.07a' into locking/kcsanIngo Molnar1-7/+17
Pull KCSAN updates from Paul E. McKenney: - UBSAN fixes - inlining updates - documentation updates Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-23kasan: Add riscv to KASAN documentation.Nick Hu1-2/+2
Add riscv to the KASAN documentation to mention that riscv is supporting generic kasan now. Signed-off-by: Nick Hu <nickhu@andestech.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-01-10kunit: update documentation to describe module-based buildAlan Maguire3-1/+21
Documentation should describe how to build kunit and tests as modules. Co-developed-by: Knut Omang <knut.omang@oracle.com> Signed-off-by: Knut Omang <knut.omang@oracle.com> Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-01-07kcsan: Document static blacklisting optionsMarco Elver1-7/+17
Updates the section on "Selective analysis", listing all available options to blacklist reporting data races for: specific accesses, functions, compilation units, and entire directories. These options should provide adequate control for maintainers to opt out of KCSAN analysis at varying levels of granularity. It is hoped to provide the required control to reflect preferences for handling data races across the kernel. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-06Merge tag 'v5.5-rc5' into locking/kcsan, to resolve conflictIngo Molnar1-5/+5
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-05kcov: fix struct layout for kcov_remote_argAndrey Konovalov1-5/+5
Make the layout of kcov_remote_arg the same for 32-bit and 64-bit code. This makes it more convenient to write userspace apps that can be compiled into 32-bit or 64-bit binaries and still work with the same 64-bit kernel. Also use proper __u32 types in uapi headers instead of unsigned ints. Link: http://lkml.kernel.org/r/9e91020876029cfefc9211ff747685eba9536426.1575638983.git.andreyknvl@google.com Fixes: eec028c9386ed1a ("kcov: remote coverage support") Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Marco Elver <elver@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Felipe Balbi <balbi@kernel.org> Cc: Chunfeng Yun <chunfeng.yun@mediatek.com> Cc: "Jacky . Cao @ sony . com" <Jacky.Cao@sony.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Marco Elver <elver@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-30Merge tag 'v5.5-rc4' into locking/kcsan, to resolve conflictsIngo Molnar12-5/+1180
Conflicts: init/main.c lib/Kconfig.debug Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-23kunit: Rename 'kunitconfig' to '.kunitconfig'SeongJae Park1-7/+5
This commit renames 'kunitconfig' to '.kunitconfig' so that it can be automatically ignored by git and do not disturb people who want to type 'kernel/' by pressing only the 'k' and then 'tab' key. Signed-off-by: SeongJae Park <sjpark@amazon.de> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Tested-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2019-12-23docs/kunit/start: Use in-tree 'kunit_defconfig'SeongJae Park1-2/+1
The kunit doc suggests users to get the default `kunitconfig` from an external git tree. However, the file is already located under the `arch/um/configs/` of the kernel tree. Because the local file is easier to access and maintain, this commit updates the doc to use it. Signed-off-by: SeongJae Park <sjpark@amazon.de> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Tested-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2019-12-11selftests: Fix dangling documentation references to kselftest_module.shMichael Ellerman1-4/+4
Commit c78fd76f2b67 ("selftests: Move kselftest_module.sh into kselftest/") moved kselftest_module.sh but missed updating a few references to the path in documentation. Fixes: c78fd76f2b67 ("selftests: Move kselftest_module.sh into kselftest/") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2019-12-09Documentation: kunit: add documentation for kunit_toolBrendan Higgins3-1/+62
Add documentation for the Python script used to build, run, and collect results from the kernel known as kunit_tool. kunit_tool (tools/testing/kunit/kunit.py) was already added in previous commits. Signed-off-by: Brendan Higgins <brendanhiggins@google.com> Reviewed-by: David Gow <davidgow@google.com> Cc: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2019-12-09Documentation: kunit: fix typos and gramatical errorsBrendan Higgins2-16/+16
Fix typos and gramatical errors in the Getting Started and Usage guide for KUnit. Reported-by: Randy Dunlap <rdunlap@infradead.org> Link: https://patchwork.kernel.org/patch/11156481/ Reported-by: Rinat Ibragimov <ibragimovrinat@mail.ru> Link: https://github.com/google/kunit-docs/issues/1 Signed-off-by: Brendan Higgins <brendanhiggins@google.com> Reviewed-by: David Gow <davidgow@google.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2019-12-05kcov: remote coverage supportAndrey Konovalov1-0/+129
Patch series " kcov: collect coverage from usb and vhost", v3. This patchset extends kcov to allow collecting coverage from backgound kernel threads. This extension requires custom annotations for each of the places where coverage collection is desired. This patchset implements this for hub events in the USB subsystem and for vhost workers. See the first patch description for details about the kcov extension. The other two patches apply this kcov extension to USB and vhost. Examples of other subsystems that might potentially benefit from this when custom annotations are added (the list is based on process_one_work() callers for bugs recently reported by syzbot): 1. fs: writeback wb_workfn() worker, 2. net: addrconf_dad_work()/addrconf_verify_work() workers, 3. net: neigh_periodic_work() worker, 4. net/p9: p9_write_work()/p9_read_work() workers, 5. block: blk_mq_run_work_fn() worker. These patches have been used to enable coverage-guided USB fuzzing with syzkaller for the last few years, see the details here: https://github.com/google/syzkaller/blob/master/docs/linux/external_fuzzing_usb.md This patchset has been pushed to the public Linux kernel Gerrit instance: https://linux-review.googlesource.com/c/linux/kernel/git/torvalds/linux/+/1524 This patch (of 3): Add background thread coverage collection ability to kcov. With KCOV_ENABLE coverage is collected only for syscalls that are issued from the current process. With KCOV_REMOTE_ENABLE it's possible to collect coverage for arbitrary parts of the kernel code, provided that those parts are annotated with kcov_remote_start()/kcov_remote_stop(). This allows to collect coverage from two types of kernel background threads: the global ones, that are spawned during kernel boot in a limited number of instances (e.g. one USB hub_event() worker thread is spawned per USB HCD); and the local ones, that are spawned when a user interacts with some kernel interface (e.g. vhost workers). To enable collecting coverage from a global background thread, a unique global handle must be assigned and passed to the corresponding kcov_remote_start() call. Then a userspace process can pass a list of such handles to the KCOV_REMOTE_ENABLE ioctl in the handles array field of the kcov_remote_arg struct. This will attach the used kcov device to the code sections, that are referenced by those handles. Since there might be many local background threads spawned from different userspace processes, we can't use a single global handle per annotation. Instead, the userspace process passes a non-zero handle through the common_handle field of the kcov_remote_arg struct. This common handle gets saved to the kcov_handle field in the current task_struct and needs to be passed to the newly spawned threads via custom annotations. Those threads should in turn be annotated with kcov_remote_start()/kcov_remote_stop(). Internally kcov stores handles as u64 integers. The top byte of a handle is used to denote the id of a subsystem that this handle belongs to, and the lower 4 bytes are used to denote the id of a thread instance within that subsystem. A reserved value 0 is used as a subsystem id for common handles as they don't belong to a particular subsystem. The bytes 4-7 are currently reserved and must be zero. In the future the number of bytes used for the subsystem or handle ids might be increased. When a particular userspace process collects coverage by via a common handle, kcov will collect coverage for each code section that is annotated to use the common handle obtained as kcov_handle from the current task_struct. However non common handles allow to collect coverage selectively from different subsystems. Link: http://lkml.kernel.org/r/e90e315426a384207edbec1d6aa89e43008e4caf.1572366574.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: David Windsor <dwindsor@gmail.com> Cc: Elena Reshetova <elena.reshetova@intel.com> Cc: Anders Roxell <anders.roxell@linaro.org> Cc: Alexander Potapenko <glider@google.com> Cc: Marco Elver <elver@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-02Merge tag 'docs-5.5a' of git://git.lwn.net/linuxLinus Torvalds1-1/+1
Pull Documentation updates from Jonathan Corbet: "Here are the main documentation changes for 5.5: - Various kerneldoc script enhancements. - More RST conversions; those are slowing down as we run out of things to convert, but we're a ways from done still. - Dan's "maintainer profile entry" work landed at last. Now we just need to get maintainers to fill in the profiles... - A reworking of the parallel build setup to work better with a variety of systems (and to not take over huge systems entirely in particular). - The MAINTAINERS file is now converted to RST during the build. Hopefully nobody ever tries to print this thing, or they will need to load a lot of paper. - A script and documentation making it easy for maintainers to add Link: tags at commit time. Also included is the removal of a bunch of spurious CR characters" * tag 'docs-5.5a' of git://git.lwn.net/linux: (91 commits) docs: remove a bunch of stray CRs docs: fix up the maintainer profile document libnvdimm, MAINTAINERS: Maintainer Entry Profile Maintainer Handbook: Maintainer Entry Profile MAINTAINERS: Reclaim the P: tag for Maintainer Entry Profile docs, parallelism: Rearrange how jobserver reservations are made docs, parallelism: Do not leak blocking mode to other readers docs, parallelism: Fix failure path and add comment Documentation: Remove bootmem_debug from kernel-parameters.txt Documentation: security: core.rst: fix warnings Documentation/process/howto/kokr: Update for 4.x -> 5.x versioning Documentation/translation: Use Korean for Korean translation title docs/memory-barriers.txt: Remove remaining references to mmiowb() docs/memory-barriers.txt/kokr: Update I/O section to be clearer about CPU vs thread docs/memory-barriers.txt/kokr: Fix style, spacing and grammar in I/O section Documentation/kokr: Kill all references to mmiowb() docs/memory-barriers.txt/kokr: Rewrite "KERNEL I/O BARRIER EFFECTS" section docs: Add initial documentation for devfreq Documentation: Document how to get links with git am docs: Add request_irq() documentation ...
2019-12-01kasan: support backing vmalloc space with real shadow memoryDaniel Axtens1-0/+63
Patch series "kasan: support backing vmalloc space with real shadow memory", v11. Currently, vmalloc space is backed by the early shadow page. This means that kasan is incompatible with VMAP_STACK. This series provides a mechanism to back vmalloc space with real, dynamically allocated memory. I have only wired up x86, because that's the only currently supported arch I can work with easily, but it's very easy to wire up other architectures, and it appears that there is some work-in-progress code to do this on arm64 and s390. This has been discussed before in the context of VMAP_STACK: - https://bugzilla.kernel.org/show_bug.cgi?id=202009 - https://lkml.org/lkml/2018/7/22/198 - https://lkml.org/lkml/2019/7/19/822 In terms of implementation details: Most mappings in vmalloc space are small, requiring less than a full page of shadow space. Allocating a full shadow page per mapping would therefore be wasteful. Furthermore, to ensure that different mappings use different shadow pages, mappings would have to be aligned to KASAN_SHADOW_SCALE_SIZE * PAGE_SIZE. Instead, share backing space across multiple mappings. Allocate a backing page when a mapping in vmalloc space uses a particular page of the shadow region. This page can be shared by other vmalloc mappings later on. We hook in to the vmap infrastructure to lazily clean up unused shadow memory. Testing with test_vmalloc.sh on an x86 VM with 2 vCPUs shows that: - Turning on KASAN, inline instrumentation, without vmalloc, introuduces a 4.1x-4.2x slowdown in vmalloc operations. - Turning this on introduces the following slowdowns over KASAN: * ~1.76x slower single-threaded (test_vmalloc.sh performance) * ~2.18x slower when both cpus are performing operations simultaneously (test_vmalloc.sh sequential_test_order=1) This is unfortunate but given that this is a debug feature only, not the end of the world. The benchmarks are also a stress-test for the vmalloc subsystem: they're not indicative of an overall 2x slowdown! This patch (of 4): Hook into vmalloc and vmap, and dynamically allocate real shadow memory to back the mappings. Most mappings in vmalloc space are small, requiring less than a full page of shadow space. Allocating a full shadow page per mapping would therefore be wasteful. Furthermore, to ensure that different mappings use different shadow pages, mappings would have to be aligned to KASAN_SHADOW_SCALE_SIZE * PAGE_SIZE. Instead, share backing space across multiple mappings. Allocate a backing page when a mapping in vmalloc space uses a particular page of the shadow region. This page can be shared by other vmalloc mappings later on. We hook in to the vmap infrastructure to lazily clean up unused shadow memory. To avoid the difficulties around swapping mappings around, this code expects that the part of the shadow region that covers the vmalloc space will not be covered by the early shadow page, but will be left unmapped. This will require changes in arch-specific code. This allows KASAN with VMAP_STACK, and may be helpful for architectures that do not have a separate module space (e.g. powerpc64, which I am currently working on). It also allows relaxing the module alignment back to PAGE_SIZE. Testing with test_vmalloc.sh on an x86 VM with 2 vCPUs shows that: - Turning on KASAN, inline instrumentation, without vmalloc, introuduces a 4.1x-4.2x slowdown in vmalloc operations. - Turning this on introduces the following slowdowns over KASAN: * ~1.76x slower single-threaded (test_vmalloc.sh performance) * ~2.18x slower when both cpus are performing operations simultaneously (test_vmalloc.sh sequential_test_order=3D1) This is unfortunate but given that this is a debug feature only, not the end of the world. The full benchmark results are: Performance No KASAN KASAN original x baseline KASAN vmalloc x baseline x KASAN fix_size_alloc_test 662004 11404956 17.23 19144610 28.92 1.68 full_fit_alloc_test 710950 12029752 16.92 13184651 18.55 1.10 long_busy_list_alloc_test 9431875 43990172 4.66 82970178 8.80 1.89 random_size_alloc_test 5033626 23061762 4.58 47158834 9.37 2.04 fix_align_alloc_test 1252514 15276910 12.20 31266116 24.96 2.05 random_size_align_alloc_te 1648501 14578321 8.84 25560052 15.51 1.75 align_shift_alloc_test 147 830 5.65 5692 38.72 6.86 pcpu_alloc_test 80732 125520 1.55 140864 1.74 1.12 Total Cycles 119240774314 763211341128 6.40 1390338696894 11.66 1.82 Sequential, 2 cpus No KASAN KASAN original x baseline KASAN vmalloc x baseline x KASAN fix_size_alloc_test 1423150 14276550 10.03 27733022 19.49 1.94 full_fit_alloc_test 1754219 14722640 8.39 15030786 8.57 1.02 long_busy_list_alloc_test 11451858 52154973 4.55 107016027 9.34 2.05 random_size_alloc_test 5989020 26735276 4.46 68885923 11.50 2.58 fix_align_alloc_test 2050976 20166900 9.83 50491675 24.62 2.50 random_size_align_alloc_te 2858229 17971700 6.29 38730225 13.55 2.16 align_shift_alloc_test 405 6428 15.87 26253 64.82 4.08 pcpu_alloc_test 127183 151464 1.19 216263 1.70 1.43 Total Cycles 54181269392 308723699764 5.70 650772566394 12.01 2.11 fix_size_alloc_test 1420404 14289308 10.06 27790035 19.56 1.94 full_fit_alloc_test 1736145 14806234 8.53 15274301 8.80 1.03 long_busy_list_alloc_test 11404638 52270785 4.58 107550254 9.43 2.06 random_size_alloc_test 6017006 26650625 4.43 68696127 11.42 2.58 fix_align_alloc_test 2045504 20280985 9.91 50414862 24.65 2.49 random_size_align_alloc_te 2845338 17931018 6.30 38510276 13.53 2.15 align_shift_alloc_test 472 3760 7.97 9656 20.46 2.57 pcpu_alloc_test 118643 132732 1.12 146504 1.23 1.10 Total Cycles 54040011688 309102805492 5.72 651325675652 12.05 2.11 [dja@axtens.net: fixups] Link: http://lkml.kernel.org/r/20191120052719.7201-1-dja@axtens.net Link: https://bugzilla.kernel.org/show_bug.cgi?id=3D202009 Link: http://lkml.kernel.org/r/20191031093909.9228-2-dja@axtens.net Signed-off-by: Mark Rutland <mark.rutland@arm.com> [shadow rework] Signed-off-by: Daniel Axtens <dja@axtens.net> Co-developed-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Vasily Gorbik <gor@linux.ibm.com> Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Qian Cai <cai@lca.pw> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-26Merge tag 'linux-kselftest-5.5-rc1-kunit' of ↵Linus Torvalds7-0/+925
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kselftest KUnit support gtom Shuah Khan: "This adds KUnit, a lightweight unit testing and mocking framework for the Linux kernel from Brendan Higgins. KUnit is not an end-to-end testing framework. It is currently supported on UML and sub-systems can write unit tests and run them in UML env. KUnit documentation is included in this update. In addition, this Kunit update adds 3 new kunit tests: - proc sysctl test from Iurii Zaikin - the 'list' doubly linked list test from David Gow - ext4 tests for decoding extended timestamps from Iurii Zaikin In the future KUnit will be linked to Kselftest framework to provide a way to trigger KUnit tests from user-space" * tag 'linux-kselftest-5.5-rc1-kunit' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (23 commits) lib/list-test: add a test for the 'list' doubly linked list ext4: add kunit test for decoding extended timestamps Documentation: kunit: Fix verification command kunit: Fix '--build_dir' option kunit: fix failure to build without printk MAINTAINERS: add proc sysctl KUnit test to PROC SYSCTL section kernel/sysctl-test: Add null pointer test for sysctl.c:proc_dointvec() MAINTAINERS: add entry for KUnit the unit testing framework Documentation: kunit: add documentation for KUnit kunit: defconfig: add defconfigs for building KUnit tests kunit: tool: add Python wrappers for running KUnit tests kunit: test: add tests for KUnit managed resources kunit: test: add the concept of assertions kunit: test: add tests for kunit test abort kunit: test: add support for test abort objtool: add kunit_try_catch_throw to the noreturn list kunit: test: add initial tests lib: enable building KUnit in lib/ kunit: test: add the concept of expectations kunit: test: add assertion printing library ...
2019-11-16kcsan: Add Documentation entry in dev-toolsMarco Elver2-0/+257
Signed-off-by: Marco Elver <elver@google.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2019-10-29Merge tag 'v5.4-rc4' into docs-nextJonathan Corbet2-0/+19
I need to pick up the independent changes made to Documentation/core-api/memory-allocation.rst to be able to merge further work without creating a total mess.
2019-10-15mm, page_owner: decouple freeing stack trace from debug_pageallocVlastimil Babka1-0/+3
Commit 8974558f49a6 ("mm, page_owner, debug_pagealloc: save and dump freeing stack trace") enhanced page_owner to also store freeing stack trace, when debug_pagealloc is also enabled. KASAN would also like to do this [1] to improve error reports to debug e.g. UAF issues. Kirill has suggested that the freeing stack trace saving should be also possible to be enabled separately from KASAN or debug_pagealloc, i.e. with an extra boot option. Qian argued that we have enough options already, and avoiding the extra overhead is not worth the complications in the case of a debugging option. Kirill noted that the extra stack handle in struct page_owner requires 0.1% of memory. This patch therefore enables free stack saving whenever page_owner is enabled, regardless of whether debug_pagealloc or KASAN is also enabled. KASAN kernels booted with page_owner=on will thus benefit from the improved error reports. [1] https://bugzilla.kernel.org/show_bug.cgi?id=203967 [vbabka@suse.cz: v3] Link: http://lkml.kernel.org/r/20191007091808.7096-3-vbabka@suse.cz Link: http://lkml.kernel.org/r/20190930122916.14969-3-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Qian Cai <cai@lca.pw> Suggested-by: Dmitry Vyukov <dvyukov@google.com> Suggested-by: Walter Wu <walter-zh.wu@mediatek.com> Suggested-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Suggested-by: Qian Cai <cai@lca.pw> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-08Documentation: kunit: Fix verification commandSeongJae Park1-1/+1
kunit wrapper script ('kunit.py') receives a sub-command (only 'run' for now) as its argument. If no sub-command is given, it prints help message and just quit. However, an example command in the kunit documentation for a verification of kunit is missing the sub-command. This commit fixes the example. Signed-off-by: SeongJae Park <sj38.park@gmail.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2019-10-01kselftest: add capability to skip chosen TARGETSCristian Marussi1-0/+16
Let the user specify an optional TARGETS skiplist through the new optional SKIP_TARGETS Makefile variable. It is easier to skip at will using a reduced and well defined list of possibly problematic targets with SKIP_TARGETS than to provide a partially stripped down list of good targets using the usual TARGETS variable. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2019-10-01docs: kmemleak: DEBUG_KMEMLEAK_EARLY_LOG_SIZE changed namesJeremy Cline1-1/+1
Commit c5665868183f ("mm: kmemleak: use the memory pool for early allocations") renamed CONFIG_DEBUG_KMEMLEAK_EARLY_LOG_SIZE to CONFIG_DEBUG_KMEMLEAK_MEM_POOL_SIZE. Update the documentation reference to reflect that. Fixes: c5665868183f ("mm: kmemleak: use the memory pool for early allocations") Signed-off-by: Jeremy Cline <jcline@redhat.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>