summaryrefslogtreecommitdiffstats
path: root/scripts
AgeCommit message (Collapse)AuthorFilesLines
2019-05-14scripts/gdb: print cached rate in lx-clk-summaryLeonard Crestez2-7/+18
The clk rate is always stored in clk_core but might be out of date and require calls to update from hardware. Deal with that case by printing a (c) suffix. Link: http://lkml.kernel.org/r/1a474318982a5f0125f2360c4161029b17f56bd1.1556881728.git.leonard.crestez@nxp.com Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Kieran Bingham <kbingham@kernel.org> Cc: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14scripts/gdb: clean up error handling in list helpersLeonard Crestez1-8/+2
An incorrect argument to list_for_each is an internal error in gdb scripts so a TypeError should be raised. The gdb.GdbError exception type is intended for user errors such as incorrect invocation. Drop the type assertion in list_for_each_entry because list_for_each isn't going to suddenly yield something else. Applies to both list and hlist Link: http://lkml.kernel.org/r/c1d3fd4db13d999a3ba57f5bbc1924862d824f61.1556881728.git.leonard.crestez@nxp.com Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> Reviewed-by: Stephen Boyd <sboyd@kernel.org> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Kieran Bingham <kbingham@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14scripts/gdb: add $lx_clk_core_lookup functionLeonard Crestez1-0/+23
Finding an individual clk_core requires walking the tree which can be quite complicated so add a helper for easy access. (gdb) print *(struct clk_scu*)$lx_clk_core_lookup("uart0_clk")->hw Link: http://lkml.kernel.org/r/Message-ID: Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Kieran Bingham <kbingham@kernel.org> Cc: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14scripts/gdb: initial clk support: lx-clk-summaryLeonard Crestez2-0/+47
Add an lx-clk-summary command which prints a subset of /sys/kernel/debug/clk/clk_summary. This can be used to examine hangs caused by clk not being enabled. Link: http://lkml.kernel.org/r/Message-ID: Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Kieran Bingham <kbingham@kernel.org> Cc: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14scripts/gdb: add hlist utilitiesLeonard Crestez1-0/+23
This allows easily examining kernel hlists in python. Link: http://lkml.kernel.org/r/Message-ID: Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> Reviewed-by: Stephen Boyd <sboyd@kernel.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Kieran Bingham <kbingham@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14scripts/gdb: silence pep8 checksStephen Boyd5-5/+16
These scripts have some pep8 style warnings. Fix them up so that this directory is all pep8 clean. Link: http://lkml.kernel.org/r/20190329220844.38234-6-swboyd@chromium.org Signed-off-by: Stephen Boyd <swboyd@chromium.org> Cc: Douglas Anderson <dianders@chromium.org> Cc: Nikolay Borisov <n.borisov.lkml@gmail.com> Cc: Kieran Bingham <kbingham@kernel.org> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jackie Liu <liuyun01@kylinos.cn> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14scripts/gdb: add a timer list commandStephen Boyd3-0/+233
Implement a command to print the timer list, much like how /proc/timer_list is implemented. This can be used to look at the pending timers on a crashed system. [swboyd@chromium.org: v2] Link: http://lkml.kernel.org/r/20190329220844.38234-5-swboyd@chromium.org Link: http://lkml.kernel.org/r/20190325184522.260535-5-swboyd@chromium.org Signed-off-by: Stephen Boyd <swboyd@chromium.org> Cc: Douglas Anderson <dianders@chromium.org> Cc: Nikolay Borisov <n.borisov.lkml@gmail.com> Cc: Kieran Bingham <kbingham@kernel.org> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jackie Liu <liuyun01@kylinos.cn> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14scripts/gdb: add rb tree iterating utilitiesStephen Boyd2-0/+178
Implement gdb functions for rb_first(), rb_last(), rb_next(), and rb_prev(). These can be useful to iterate through the kernel's red-black trees. [swboyd@chromium.org: v2] Link: http://lkml.kernel.org/r/20190329220844.38234-4-swboyd@chromium.org Link: http://lkml.kernel.org/r/20190325184522.260535-4-swboyd@chromium.org Signed-off-by: Stephen Boyd <swboyd@chromium.org> Cc: Douglas Anderson <dianders@chromium.org> Cc: Nikolay Borisov <n.borisov.lkml@gmail.com> Cc: Kieran Bingham <kbingham@kernel.org> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jackie Liu <liuyun01@kylinos.cn> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14scripts/gdb: add kernel config dumping commandStephen Boyd2-0/+45
lx-configdump <file> dumps the contents of the gzipped .config to a text file when the config is included in the kernel with CONFIG_IKCONFIG. By default, the file written is called config.txt, but it can be any user supplied filename as well. If the kernel config is in a module (configs.ko), then it can be loaded along with symbols for the module loaded with 'lx-symbols' and then this command will still work. Obviously if you have the whole vmlinux then this can also be achieved with scripts/extract-ikconfig, but this gdb script can be useful to confirm that the memory contents of the config in memory and the vmlinux contents on disk match what is expected. [swboyd@chromium.org: v2] Link: http://lkml.kernel.org/r/20190329220844.38234-3-swboyd@chromium.org Link: http://lkml.kernel.org/r/20190325184522.260535-3-swboyd@chromium.org Signed-off-by: Stephen Boyd <swboyd@chromium.org> Cc: Douglas Anderson <dianders@chromium.org> Cc: Nikolay Borisov <n.borisov.lkml@gmail.com> Cc: Kieran Bingham <kbingham@kernel.org> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jackie Liu <liuyun01@kylinos.cn> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14scripts/gdb: find vmlinux where it was beforeStephen Boyd1-1/+5
Patch series "gdb script for kconfig and timer list". This is a handful of changes to the kernel's gdb scripts to do some more debugging with kgdb. The first patch allows the vmlinux to be reloaded from where it was specified on the command line so that this set of scripts can be used from anywhere. The second patch adds a script to dump the config.gz to a file on the host debugging machine. The third patch adds some rb tree utilities and the last patch uses those rb tree walking utilities to dump out the contents of /proc/timer_list from a system under debug. This patch (of 5): If I run 'gdb <path/to/vmlinux>' and there's the vmlinux-gdb.py file there I can properly see symbols and use the lx commands provided by the GDB scripts. But once I run 'lx-symbols' at the command prompt, gdb reloads the vmlinux symbols assuming that this script was run from the directory that has vmlinux at the root. That isn't always true, but we could just look and see what symbols were already loaded and use that instead. Let's do that so this can work by being invoked anywhere. Link: http://lkml.kernel.org/r/20190325184522.260535-2-swboyd@chromium.org Signed-off-by: Stephen Boyd <swboyd@chromium.org> Cc: Douglas Anderson <dianders@chromium.org> Cc: Nikolay Borisov <n.borisov.lkml@gmail.com> Cc: Kieran Bingham <kbingham@kernel.org> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jackie Liu <liuyun01@kylinos.cn> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14kconfig: make conf_get_autoconfig_name() staticMasahiro Yamada2-2/+1
This is only used in confdata.c Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-14kconfig: use snprintf for formatting pathnamesJacob Garber2-2/+3
Valid pathnames will never exceed PATH_MAX, but these file names are unsanitized and can cause buffer overflow if set incorrectly. Use snprintf to avoid this. This was flagged during a Coverity scan of the coreboot project, which also uses kconfig for its build system. Signed-off-by: Jacob Garber <jgarber1@ualberta.ca> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-14kconfig: remove useless NULL pointer check in conf_write_dep()Masahiro Yamada1-2/+0
conf_write_dep() has just one caller: conf_write_dep("include/config/auto.conf.cmd"); "name" always points to a valid string. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-13Merge tag 'gcc-plugins-v5.2-rc1' of ↵Linus Torvalds1-1/+1
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull gcc plugin fix from Kees Cook: "Fix ARM stack-protector-per-task plugin build for older GCC < 6 (Chris Packham)" * tag 'gcc-plugins-v5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/kees/linux: gcc-plugins: arm_ssp_per_task_plugin: Fix for older GCC < 6
2019-05-13bpf: fix script for generating man page on BPF helpersQuentin Monnet1-4/+4
The script broke on parsing function prototype for bpf_strtoul(). This is because the last argument for the function is a pointer to an "unsigned long". The current version of the script only accepts "const" and "struct", but not "unsigned", at the beginning of argument types made of several words. One solution could be to add "unsigned" to the list, but the issue could come up again in the future (what about "long int"?). It turns out we do not need to have such restrictions on the words: so let's simply accept any series of words instead. Reported-by: Yonghong Song <yhs@fb.com> Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-05-10gcc-plugins: arm_ssp_per_task_plugin: Fix for older GCC < 6Chris Packham1-1/+1
Use gen_rtx_set instead of gen_rtx_SET. The former is a wrapper macro that handles the difference between GCC versions implementing the latter. This fixes the following error on my system with g++ 5.4.0 as the host compiler HOSTCXX -fPIC scripts/gcc-plugins/arm_ssp_per_task_plugin.o scripts/gcc-plugins/arm_ssp_per_task_plugin.c:42:14: error: macro "gen_rtx_SET" requires 3 arguments, but only 2 given mask)), ^ scripts/gcc-plugins/arm_ssp_per_task_plugin.c: In function ‘unsigned int arm_pertask_ssp_rtl_execute()’: scripts/gcc-plugins/arm_ssp_per_task_plugin.c:39:20: error: ‘gen_rtx_SET’ was not declared in this scope emit_insn_before(gen_rtx_SET Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Fixes: 189af4657186 ("ARM: smp: add support for per-task stack canaries") Cc: stable@vger.kernel.org Tested-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2019-05-11kconfig: make parent directories for the saved .config as neededMasahiro Yamada3-3/+5
With menuconfig / nconfig, users can input any file path from the "Save" menu, but it fails if the parent directory does not exist. Why not create the parent directory automatically. I think this is a user-friendly behavior. I changed the error messages in menuconfig / nconfig. "Nonexistent directory" is no longer the most likely reason of the failure. Perhaps, the user specified the existing directory, or attempted to write to the location without write permission. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-11kconfig: do not write .config if the content is the sameMasahiro Yamada1-0/+54
Kconfig updates the .config when it exits even if its content is exactly the same as before. Since its timestamp becomes newer than that of other build artifacts, additional processing is invoked, which is annoying. - syncconfig is invoked to update include/config/auto.conf, etc. - kernel/configs.o is recompiled if CONFIG_IKCONFIG is enabled, then vmlinux is relinked as well. If the .config is not changed at all, we do not have to even touch it. Just bail out showing "No change to .config". $ make allmodconfig scripts/kconfig/conf --allmodconfig Kconfig # # configuration written to .config # $ make allmodconfig scripts/kconfig/conf --allmodconfig Kconfig # # No change to .config # Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-11kconfig: do not accept a directory for configuration outputMasahiro Yamada1-34/+24
Currently, conf_write() can be called with a directory name instead of a file name. As far as I see, this can happen for menuconfig, nconfig, gconfig. If it is given with a directory path, conf_write() kindly appends getenv("KCONFIG_CONFIG"), but this ends up with hacky dir/basename handling, and screwed up in corner-cases like "what if KCONFIG_CONFIG is an absolute path?" as discussed before: https://patchwork.kernel.org/patch/9910037/ Since conf_write() is already messed up, I'd say "do not do it". Please pass a file path all the time. If a directory path is specified for the configuration output, conf_write() will simply error out. Now that the tmp file is created in the same directory as the .config, the previously reported "what if KCONFIG_CONFIG points to a different file system?" has been solved. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Nicolas Porcel <nicolasporcel06@gmail.com>
2019-05-09kconfig: remove trailing whitespacesMasahiro Yamada2-2/+2
There are still some trailing whitespaces under scripts/kconfig/tests/, but they must be kept. Otherwise, "make testconfig" would break. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-08Merge tag 'docs-5.2' of git://git.lwn.net/linuxLinus Torvalds3-0/+51
Pull documentation updates from Jonathan Corbet: "A reasonably busy cycle for docs, including: - Lots of work on the Chinese and Italian translations - Some license-rules clarifications from Christoph - Various build-script fixes - A new document on memory models - RST conversion of the live-patching docs - The usual collection of typo fixes and corrections" * tag 'docs-5.2' of git://git.lwn.net/linux: (140 commits) docs/livepatch: Unify style of livepatch documentation in the ReST format docs: livepatch: convert docs to ReST and rename to *.rst scripts/documentation-file-ref-check: detect broken :doc:`foo` scripts/documentation-file-ref-check: don't parse Next/ dir LICENSES: Rename other to deprecated LICENSES: Clearly mark dual license only licenses docs: Don't reference the ZLib license in license-rules.rst docs/vm: Minor editorial changes in the THP and hugetlbfs docs/vm: add documentation of memory models doc:it_IT: translation alignment doc: fix typo in PGP guide dontdiff: update with Kconfig build artifacts docs/zh_CN: fix typos in 1.Intro.rst file docs/zh_CN: redirect CoC docs to Chinese version doc: mm: migration doesn't use FOLL_SPLIT anymore docs: doc-guide: remove the extension from .rst files doc: kselftest: Fix KBUILD_OUTPUT usage instructions docs: trace: fix some Sphinx warnings docs: speculation.txt: mark example blocks as such docs: ntb.txt: add blank lines to clean up some Sphinx warnings ...
2019-05-08Merge tag 'kbuild-v5.2' of ↵Linus Torvalds10-32/+13
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - allow users to invoke 'make' out of the source tree - refactor scripts/mkmakefile - deprecate KBUILD_SRC, which was used to track the source tree location for O= build. - fix recordmcount.pl in case objdump output is localized - turn unresolved symbols in external modules to errors from warnings by default; pass KBUILD_MODPOST_WARN=1 to get them back to warnings - generate modules.builtin.modinfo to collect .modinfo data from built-in modules - misc Makefile cleanups * tag 'kbuild-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (21 commits) .gitignore: add more all*.config patterns moduleparam: Save information about built-in modules in separate file Remove MODULE_ALIAS() calls that take undefined macro .gitignore: add leading and trailing slashes to generated directories scripts/tags.sh: fix direct execution of scripts/tags.sh scripts: override locale from environment when running recordmcount.pl samples: kobject: allow CONFIG_SAMPLE_KOBJECT to become y samples: seccomp: turn CONFIG_SAMPLE_SECCOMP into a bool option kbuild: move Documentation to vmlinux-alldirs kbuild: move samples/ to KBUILD_VMLINUX_OBJS modpost: make KBUILD_MODPOST_WARN also configurable for external modules kbuild: check arch/$(SRCARCH)/include/generated before out-of-tree build kbuild: remove unneeded dependency for include/config/kernel.release memory: squash drivers/memory/Makefile.asm-offsets kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree build kbuild: mkmakefile: generate a simple wrapper of top Makefile kbuild: mkmakefile: do not check the generated Makefile marker kbuild: allow Kbuild to start from any directory kbuild: pass $(MAKECMDGOALS) to sub-make as is kbuild: fix warning "overriding recipe for target 'Makefile'" ...
2019-05-08Merge tag 'csky-for-linus-5.2-rc1' of git://github.com/c-sky/csky-linuxLinus Torvalds1-0/+3
Pull arch/csky updates from Guo Ren: - Fixup vdsp&fpu issues in kernel - Add dynamic function tracer - Use in_syscall & forget_syscall instead of r11_sig - Reconstruct signal processing - Support dynamic start physical address - Fixup wrong update_mmu_cache implementation - Support vmlinux bootup with MMU off - Use va_pa_offset instead of phys_offset - Fixup syscall_trace return processing flow - Add perf callchain support - Add perf_arch_fetch_caller_regs support - Add page fault perf event support - Add support for perf registers sampling * tag 'csky-for-linus-5.2-rc1' of git://github.com/c-sky/csky-linux: csky/syscall_trace: Fixup return processing flow csky: Fixup compile warning csky: Add support for perf registers sampling csky: add page fault perf event support csky: Use va_pa_offset instead of phys_offset csky: Support vmlinux bootup with MMU off csky: Add perf_arch_fetch_caller_regs support csky: Fixup wrong update_mmu_cache implementation csky: Support dynamic start physical address csky: Reconstruct signal processing csky: Use in_syscall & forget_syscall instead of r11_sig csky: Add non-uapi asm/ptrace.h namespace csky: mm/fault.c: Remove duplicate header csky: remove redundant generic-y csky: Update syscall_trace_enter/exit implementation csky: Add perf callchain support csky/ftrace: Add dynamic function tracer (include graph tracer) csky: Fixup vdsp&fpu issues in kernel
2019-05-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-1/+24
Pull networking updates from David Miller: "Highlights: 1) Support AES128-CCM ciphers in kTLS, from Vakul Garg. 2) Add fib_sync_mem to control the amount of dirty memory we allow to queue up between synchronize RCU calls, from David Ahern. 3) Make flow classifier more lockless, from Vlad Buslov. 4) Add PHY downshift support to aquantia driver, from Heiner Kallweit. 5) Add SKB cache for TCP rx and tx, from Eric Dumazet. This reduces contention on SLAB spinlocks in heavy RPC workloads. 6) Partial GSO offload support in XFRM, from Boris Pismenny. 7) Add fast link down support to ethtool, from Heiner Kallweit. 8) Use siphash for IP ID generator, from Eric Dumazet. 9) Pull nexthops even further out from ipv4/ipv6 routes and FIB entries, from David Ahern. 10) Move skb->xmit_more into a per-cpu variable, from Florian Westphal. 11) Improve eBPF verifier speed and increase maximum program size, from Alexei Starovoitov. 12) Eliminate per-bucket spinlocks in rhashtable, and instead use bit spinlocks. From Neil Brown. 13) Allow tunneling with GUE encap in ipvs, from Jacky Hu. 14) Improve link partner cap detection in generic PHY code, from Heiner Kallweit. 15) Add layer 2 encap support to bpf_skb_adjust_room(), from Alan Maguire. 16) Remove SKB list implementation assumptions in SCTP, your's truly. 17) Various cleanups, optimizations, and simplifications in r8169 driver. From Heiner Kallweit. 18) Add memory accounting on TX and RX path of SCTP, from Xin Long. 19) Switch PHY drivers over to use dynamic featue detection, from Heiner Kallweit. 20) Support flow steering without masking in dpaa2-eth, from Ioana Ciocoi. 21) Implement ndo_get_devlink_port in netdevsim driver, from Jiri Pirko. 22) Increase the strict parsing of current and future netlink attributes, also export such policies to userspace. From Johannes Berg. 23) Allow DSA tag drivers to be modular, from Andrew Lunn. 24) Remove legacy DSA probing support, also from Andrew Lunn. 25) Allow ll_temac driver to be used on non-x86 platforms, from Esben Haabendal. 26) Add a generic tracepoint for TX queue timeouts to ease debugging, from Cong Wang. 27) More indirect call optimizations, from Paolo Abeni" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1763 commits) cxgb4: Fix error path in cxgb4_init_module net: phy: improve pause mode reporting in phy_print_status dt-bindings: net: Fix a typo in the phy-mode list for ethernet bindings net: macb: Change interrupt and napi enable order in open net: ll_temac: Improve error message on error IRQ net/sched: remove block pointer from common offload structure net: ethernet: support of_get_mac_address new ERR_PTR error net: usb: smsc: fix warning reported by kbuild test robot staging: octeon-ethernet: Fix of_get_mac_address ERR_PTR check net: dsa: support of_get_mac_address new ERR_PTR error net: dsa: sja1105: Fix status initialization in sja1105_get_ethtool_stats vrf: sit mtu should not be updated when vrf netdev is the link net: dsa: Fix error cleanup path in dsa_init_module l2tp: Fix possible NULL pointer dereference taprio: add null check on sched_nest to avoid potential null pointer dereference net: mvpp2: cls: fix less than zero check on a u32 variable net_sched: sch_fq: handle non connected flows net_sched: sch_fq: do not assume EDT packets are ordered net: hns3: use devm_kcalloc when allocating desc_cb net: hns3: some cleanup for struct hns3_enet_ring ...
2019-05-07Merge tag 'selinux-pr-20190507' of ↵Linus Torvalds3-64/+195
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: "We've got a few SELinux patches for the v5.2 merge window, the highlights are below: - Add LSM hooks, and the SELinux implementation, for proper labeling of kernfs. While we are only including the SELinux implementation here, the rest of the LSM folks have given the hooks a thumbs-up. - Update the SELinux mdp (Make Dummy Policy) script to actually work on a modern system. - Disallow userspace to change the LSM credentials via /proc/self/attr when the task's credentials are already overridden. The change was made in procfs because all the LSM folks agreed this was the Right Thing To Do and duplicating it across each LSM was going to be annoying" * tag 'selinux-pr-20190507' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: proc: prevent changes to overridden credentials selinux: Check address length before reading address family kernfs: fix xattr name handling in LSM helpers MAINTAINERS: update SELinux file patterns selinux: avoid uninitialized variable warning selinux: remove useless assignments LSM: lsm_hooks.h - fix missing colon in docstring selinux: Make selinux_kernfs_init_security static kernfs: initialize security of newly created nodes selinux: implement the kernfs_init_security hook LSM: add new hook for kernfs node initialization kernfs: use simple_xattrs for security attributes selinux: try security xattr after genfs for kernfs filesystems kernfs: do not alloc iattrs in kernfs_xattr_get kernfs: clean up struct kernfs_iattrs scripts/selinux: fix build selinux: use kernel linux/socket.h for genheaders and mdp scripts/selinux: modernize mdp
2019-05-07Merge tag 'meminit-v5.2-rc1' of ↵Linus Torvalds1-120/+6
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull compiler-based variable initialization updates from Kees Cook: "This is effectively part of my gcc-plugins tree, but as this adds some Clang support, it felt weird to still call it "gcc-plugins". :) This consolidates Kconfig for the existing stack variable initialization (via structleak and stackleak gcc plugins) and adds Alexander Potapenko's support for Clang's new similar functionality. Summary: - Consolidate memory initialization Kconfigs (Kees) - Implement support for Clang's stack variable auto-init (Alexander)" * tag 'meminit-v5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: security: Implement Clang's stack initialization security: Move stackleak config to Kconfig.hardening security: Create "kernel hardening" config area
2019-05-07moduleparam: Save information about built-in modules in separate fileAlexey Gladkov1-0/+3
Problem: When a kernel module is compiled as a separate module, some important information about the kernel module is available via .modinfo section of the module. In contrast, when the kernel module is compiled into the kernel, that information is not available. Information about built-in modules is necessary in the following cases: 1. When it is necessary to find out what additional parameters can be passed to the kernel at boot time. 2. When you need to know which module names and their aliases are in the kernel. This is very useful for creating an initrd image. Proposal: The proposed patch does not remove .modinfo section with module information from the vmlinux at the build time and saves it into a separate file after kernel linking. So, the kernel does not increase in size and no additional information remains in it. Information is stored in the same format as in the separate modules (null-terminated string array). Because the .modinfo section is already exported with a separate modules, we are not creating a new API. It can be easily read in the userspace: $ tr '\0' '\n' < modules.builtin.modinfo ext4.softdep=pre: crc32c ext4.license=GPL ext4.description=Fourth Extended Filesystem ext4.author=Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others ext4.alias=fs-ext4 ext4.alias=ext3 ext4.alias=fs-ext3 ext4.alias=ext2 ext4.alias=fs-ext2 md_mod.alias=block-major-9-* md_mod.alias=md md_mod.description=MD RAID framework md_mod.license=GPL md_mod.parmtype=create_on_open:bool md_mod.parmtype=start_dirty_degraded:int ... Co-Developed-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org> Signed-off-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org> Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com> Acked-by: Jessica Yu <jeyu@kernel.org> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-06Merge branch 'core-objtool-for-linus' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull objtool updates from Ingo Molnar: "This is a series from Peter Zijlstra that adds x86 build-time uaccess validation of SMAP to objtool, which will detect and warn about the following uaccess API usage bugs and weirdnesses: - call to %s() with UACCESS enabled - return with UACCESS enabled - return with UACCESS disabled from a UACCESS-safe function - recursive UACCESS enable - redundant UACCESS disable - UACCESS-safe disables UACCESS As it turns out not leaking uaccess permissions outside the intended uaccess functionality is hard when the interfaces are complex and when such bugs are mostly dormant. As a bonus we now also check the DF flag. We had at least one high-profile bug in that area in the early days of Linux, and the checking is fairly simple. The checks performed and warnings emitted are: - call to %s() with DF set - return with DF set - return with modified stack frame - recursive STD - redundant CLD It's all x86-only for now, but later on this can also be used for PAN on ARM and objtool is fairly cross-platform in principle. While all warnings emitted by this new checking facility that got reported to us were fixed, there might be GCC version dependent warnings that were not reported yet - which we'll address, should they trigger. The warnings are non-fatal build warnings" * 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) mm/uaccess: Use 'unsigned long' to placate UBSAN warnings on older GCC versions x86/uaccess: Dont leak the AC flag into __put_user() argument evaluation sched/x86_64: Don't save flags on context switch objtool: Add Direction Flag validation objtool: Add UACCESS validation objtool: Fix sibling call detection objtool: Rewrite alt->skip_orig objtool: Add --backtrace support objtool: Rewrite add_ignores() objtool: Handle function aliases objtool: Set insn->func for alternatives x86/uaccess, kcov: Disable stack protector x86/uaccess, ftrace: Fix ftrace_likely_update() vs. SMAP x86/uaccess, ubsan: Fix UBSAN vs. SMAP x86/uaccess, kasan: Fix KASAN vs SMAP x86/smap: Ditch __stringify() x86/uaccess: Introduce user_access_{save,restore}() x86/uaccess, signal: Fix AC=1 bloat x86/uaccess: Always inline user_access_begin() x86/uaccess, xen: Suppress SMAP warnings ...
2019-05-06ubsan: Remove vla bound checks.Andrey Ryabinin1-1/+0
The kernel the kernel is built with -Wvla for some time, so is not supposed to have any variable length arrays. Remove vla bounds checking from ubsan since it's useless now. Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-06kbuild: tolerate missing pahole when generating BTFAndrii Nakryiko1-0/+5
When BTF generation is enabled through CONFIG_DEBUG_INFO_BTF, scripts/link-vmlinux.sh detects if pahole version is too old and gracefully continues build process, skipping BTF generation build step. But if pahole is not available, build will still fail. This patch adds check for whether pahole exists at all and bails out gracefully, if not. Cc: Alexei Starovoitov <ast@fb.com> Reported-by: Yonghong Song <yhs@fb.com> Fixes: e83b9f55448a ("kbuild: add ability to generate BTF type info for vmlinux") Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-05-03scripts/tags.sh: fix direct execution of scripts/tags.shMasahiro Yamada1-1/+1
I thought this script was run via "make tags" etc. but some people run it directly. Prior to commit a9a49c2ad9b9 ("kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree build"), in such a usecase, "tree" was set empty since KBUILD_SRC is undefined. Now, "tree" is set to "${srctree}/", which is evaluated to "/". Fix it by taking into account the case where "srctree" is unset. Link: https://lkml.org/lkml/2019/4/19/501 Fixes: a9a49c2ad9b9 ("kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree build") Reported-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-03scripts: override locale from environment when running recordmcount.plDaniel Dadap1-1/+1
recordmcount.pl uses a set of regular expressions to parse the output of objdump(1). However, if objdump(1) output is localized, it may not match the regular expressions, thereby preventing recordmcount.pl from parsing object files correctly. In order to allow recordmcount.pl to function correctly regardless of the current locale settings, set LANG=C when running objdump(1). LC_ALL is already unset in the top-level Makefile, so it is not necessary to also override that environment variable. Signed-off-by: Daniel Dadap <ddadap@nvidia.com> Reviewed-by: Robert Morell <rmorell@nvidia.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-03scripts/documentation-file-ref-check: detect broken :doc:`foo`Mauro Carvalho Chehab1-0/+29
As we keep migrating documents to ReST, we're starting to see more of such tags. Right now, all such tags are pointing to a documentation file, but regressions may be introduced. So, add a check for such kind of issues as well. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-03scripts/documentation-file-ref-check: don't parse Next/ dirMauro Carvalho Chehab1-0/+3
If one tries to run this script under linux-next, it would hit lots of false-positives, due to the tree merges that are stored under the Next/ directory. So, add a logic to ignore it. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2-2/+0
Three trivial overlapping conflicts. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-30Merge tag 'selinux-pr-20190429' of ↵Linus Torvalds2-2/+0
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux fix from Paul Moore: "One small patch for the stable folks to fix a problem when building against the latest glibc. I'll be honest and say that I'm not really thrilled with the idea of sending this up right now, but Greg is a little annoyed so here I figured I would at least send this" * tag 'selinux-pr-20190429' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: use kernel linux/socket.h for genheaders and mdp
2019-04-29selinux: use kernel linux/socket.h for genheaders and mdpPaulo Alcantara2-2/+0
When compiling genheaders and mdp from a newer host kernel, the following error happens: In file included from scripts/selinux/genheaders/genheaders.c:18: ./security/selinux/include/classmap.h:238:2: error: #error New address family defined, please update secclass_map. #error New address family defined, please update secclass_map. ^~~~~ make[3]: *** [scripts/Makefile.host:107: scripts/selinux/genheaders/genheaders] Error 1 make[2]: *** [scripts/Makefile.build:599: scripts/selinux/genheaders] Error 2 make[1]: *** [scripts/Makefile.build:599: scripts/selinux] Error 2 make[1]: *** Waiting for unfinished jobs.... Instead of relying on the host definition, include linux/socket.h in classmap.h to have PF_MAX. Cc: stable@vger.kernel.org Signed-off-by: Paulo Alcantara <paulo@paulo.ac> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> [PM: manually merge in mdp.c, subject line tweaks] Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-04-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
Two easy cases of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-24security: Move stackleak config to Kconfig.hardeningKees Cook1-51/+0
This moves the stackleak plugin options to Kconfig.hardening's memory initialization menu. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Alexander Popov <alex.popov@linux.com> Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-24security: Create "kernel hardening" config areaKees Cook1-69/+6
Right now kernel hardening options are scattered around various Kconfig files. This can be a central place to collect these kinds of options going forward. This is initially populated with the memory initialization options from the gcc-plugins. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-22csky/ftrace: Add dynamic function tracer (include graph tracer)Guo Ren1-0/+3
Support dynamic ftrace including dynamic graph tracer. Gcc-csky with -pg will produce call site in every function prologue and we can use these call site to hook trace function. gcc with -pg origin call site: push lr jbsr _mcount nop32 nop32 If the (callee - caller)'s offset is in range of bsr instruction, we'll modify code with: push lr bsr _mcount nop32 nop32 Else if the (callee - caller)'s offset is out of bsr instrunction, we'll modify code with: push lr movih r26, ... ori r26, ... jsr r26 (r26 is reserved for jsr link reg in csky abiv2 spec.) Signed-off-by: Guo Ren <ren_guo@c-sky.com>
2019-04-19locking/atomics: Don't assume that scripts are executableAndrew Morton1-1/+1
patch(1) doesn't set the x bit on files. So if someone downloads and applies patch-4.21.xz, their kernel won't build. Fix that by executing /bin/sh. Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16kbuild: handle old pahole more gracefully when generating BTFAndrii Nakryiko1-1/+1
When CONFIG_DEBUG_INFO_BTF is enabled but available version of pahole is too old to support BTF generation, build script is supposed to emit warning and proceed with the build. Due to using exit instead of return from BASH function, existing handling code prematurely exits exit code 0, not completing some of the build steps. This patch fixes issue by correctly returning just from gen_btf() function only. Fixes: e83b9f55448a ("kbuild: add ability to generate BTF type info for vmlinux") Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Alexei Starovoitov <ast@fb.com> Cc: Yonghong Song <yhs@fb.com> Cc: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-04-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller1-1/+19
Daniel Borkmann says: ==================== pull-request: bpf-next 2019-04-12 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Improve BPF verifier scalability for large programs through two optimizations: i) remove verifier states that are not useful in pruning, ii) stop walking parentage chain once first LIVE_READ is seen. Combined gives approx 20x speedup. Increase limits for accepting large programs under root, and add various stress tests, from Alexei. 2) Implement global data support in BPF. This enables static global variables for .data, .rodata and .bss sections to be properly handled which allows for more natural program development. This also opens up the possibility to optimize program workflow by compiling ELFs only once and later only rewriting section data before reload, from Daniel and with test cases and libbpf refactoring from Joe. 3) Add config option to generate BTF type info for vmlinux as part of the kernel build process. DWARF debug info is converted via pahole to BTF. Latter relies on libbpf and makes use of BTF deduplication algorithm which results in 100x savings compared to DWARF data. Resulting .BTF section is typically about 2MB in size, from Andrii. 4) Add BPF verifier support for stack access with variable offset from helpers and add various test cases along with it, from Andrey. 5) Extend bpf_skb_adjust_room() growth BPF helper to mark inner MAC header so that L2 encapsulation can be used for tc tunnels, from Alan. 6) Add support for input __sk_buff context in BPF_PROG_TEST_RUN so that users can define a subset of allowed __sk_buff fields that get fed into the test program, from Stanislav. 7) Add bpf fs multi-dimensional array tests for BTF test suite and fix up various UBSAN warnings in bpftool, from Yonghong. 8) Generate a pkg-config file for libbpf, from Luca. 9) Dump program's BTF id in bpftool, from Prashant. 10) libbpf fix to use smaller BPF log buffer size for AF_XDP's XDP program, from Magnus. 11) kallsyms related fixes for the case when symbols are not present in BPF selftests and samples, from Daniel ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-11modpost: make KBUILD_MODPOST_WARN also configurable for external modulesWiebe, Wladislav (Nokia - DE/Ulm)1-1/+1
Commit ea837f1c0503 ("kbuild: make modpost processing configurable") was intended to give KBUILD_MODPOST_WARN flexibility to be configurable. Right now KBUILD_MODPOST_WARN gets just ignored when KBUILD_EXTMOD is set which happens per default when building modules out of the tree. This change gives the opportunity to define module build behaving also in case of out of tree builds and default will become exit on error. Errors which can be detected by the build should be trapped out of the box there, unless somebody wants to notice broken stuff later at runtime. As this patch changes the default behaving from warning to error, users can consider to fix it for external module builds by: - providing module symbol table via KBUILD_EXTRA_SYMBOLS for modules which are dependent - OR getting old behaving back by passing KBUILD_MODPOST_WARN to the build Signed-off-by: Wladislav Wiebe <wladislav.wiebe@nokia.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-09kconfig: Make nconf-cfg.sh executablePetr Vorel1-0/+0
Although it's not required for the build *conf-cfg.sh scripts to be executable (they're run by CONFIG_SHELL), let's be consistent with other scripts. Signed-off-by: Petr Vorel <pvorel@suse.cz> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-06fs: stream_open - opener for stream-like files so that read and write can ↵Kirill Smelkov1-0/+363
run simultaneously without deadlock Commit 9c225f2655e3 ("vfs: atomic f_pos accesses as per POSIX") added locking for file.f_pos access and in particular made concurrent read and write not possible - now both those functions take f_pos lock for the whole run, and so if e.g. a read is blocked waiting for data, write will deadlock waiting for that read to complete. This caused regression for stream-like files where previously read and write could run simultaneously, but after that patch could not do so anymore. See e.g. commit 581d21a2d02a ("xenbus: fix deadlock on writes to /proc/xen/xenbus") which fixes such regression for particular case of /proc/xen/xenbus. The patch that added f_pos lock in 2014 did so to guarantee POSIX thread safety for read/write/lseek and added the locking to file descriptors of all regular files. In 2014 that thread-safety problem was not new as it was already discussed earlier in 2006. However even though 2006'th version of Linus's patch was adding f_pos locking "only for files that are marked seekable with FMODE_LSEEK (thus avoiding the stream-like objects like pipes and sockets)", the 2014 version - the one that actually made it into the tree as 9c225f2655e3 - is doing so irregardless of whether a file is seekable or not. See https://lore.kernel.org/lkml/53022DB1.4070805@gmail.com/ https://lwn.net/Articles/180387 https://lwn.net/Articles/180396 for historic context. The reason that it did so is, probably, that there are many files that are marked non-seekable, but e.g. their read implementation actually depends on knowing current position to correctly handle the read. Some examples: kernel/power/user.c snapshot_read fs/debugfs/file.c u32_array_read fs/fuse/control.c fuse_conn_waiting_read + ... drivers/hwmon/asus_atk0110.c atk_debugfs_ggrp_read arch/s390/hypfs/inode.c hypfs_read_iter ... Despite that, many nonseekable_open users implement read and write with pure stream semantics - they don't depend on passed ppos at all. And for those cases where read could wait for something inside, it creates a situation similar to xenbus - the write could be never made to go until read is done, and read is waiting for some, potentially external, event, for potentially unbounded time -> deadlock. Besides xenbus, there are 14 such places in the kernel that I've found with semantic patch (see below): drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write() drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write() drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write() drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write() net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write() drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write() drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write() drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write() net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write() drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write() drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write() drivers/input/misc/uinput.c:400:1-17: ERROR: uinput_fops: .read() can deadlock .write() drivers/infiniband/core/user_mad.c:985:7-23: ERROR: umad_fops: .read() can deadlock .write() drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write() In addition to the cases above another regression caused by f_pos locking is that now FUSE filesystems that implement open with FOPEN_NONSEEKABLE flag, can no longer implement bidirectional stream-like files - for the same reason as above e.g. read can deadlock write locking on file.f_pos in the kernel. FUSE's FOPEN_NONSEEKABLE was added in 2008 in a7c1b990f715 ("fuse: implement nonseekable open") to support OSSPD. OSSPD implements /dev/dsp in userspace with FOPEN_NONSEEKABLE flag, with corresponding read and write routines not depending on current position at all, and with both read and write being potentially blocking operations: See https://github.com/libfuse/osspd https://lwn.net/Articles/308445 https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1406 https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1438-L1477 https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1479-L1510 Corresponding libfuse example/test also describes FOPEN_NONSEEKABLE as "somewhat pipe-like files ..." with read handler not using offset. However that test implements only read without write and cannot exercise the deadlock scenario: https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L124-L131 https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L146-L163 https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L209-L216 I've actually hit the read vs write deadlock for real while implementing my FUSE filesystem where there is /head/watch file, for which open creates separate bidirectional socket-like stream in between filesystem and its user with both read and write being later performed simultaneously. And there it is semantically not easy to split the stream into two separate read-only and write-only channels: https://lab.nexedi.com/kirr/wendelin.core/blob/f13aa600/wcfs/wcfs.go#L88-169 Let's fix this regression. The plan is: 1. We can't change nonseekable_open to include &~FMODE_ATOMIC_POS - doing so would break many in-kernel nonseekable_open users which actually use ppos in read/write handlers. 2. Add stream_open() to kernel to open stream-like non-seekable file descriptors. Read and write on such file descriptors would never use nor change ppos. And with that property on stream-like files read and write will be running without taking f_pos lock - i.e. read and write could be running simultaneously. 3. With semantic patch search and convert to stream_open all in-kernel nonseekable_open users for which read and write actually do not depend on ppos and where there is no other methods in file_operations which assume @offset access. 4. Add FOPEN_STREAM to fs/fuse/ and open in-kernel file-descriptors via steam_open if that bit is present in filesystem open reply. It was tempting to change fs/fuse/ open handler to use stream_open instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE, and in particular GVFS which actually uses offset in its read and write handlers https://codesearch.debian.net/search?q=-%3Enonseekable+%3D https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080 https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346 https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481 so if we would do such a change it will break a real user. 5. Add stream_open and FOPEN_STREAM handling to stable kernels starting from v3.14+ (the kernel where 9c225f2655 first appeared). This will allow to patch OSSPD and other FUSE filesystems that provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE in their open handler and this way avoid the deadlock on all kernel versions. This should work because fs/fuse/ ignores unknown open flags returned from a filesystem and so passing FOPEN_STREAM to a kernel that is not aware of this flag cannot hurt. In turn the kernel that is not aware of FOPEN_STREAM will be < v3.14 where just FOPEN_NONSEEKABLE is sufficient to implement streams without read vs write deadlock. This patch adds stream_open, converts /proc/xen/xenbus to it and adds semantic patch to automatically locate in-kernel places that are either required to be converted due to read vs write deadlock, or that are just safe to be converted because read and write do not use ppos and there are no other funky methods in file_operations. Regarding semantic patch I've verified each generated change manually - that it is correct to convert - and each other nonseekable_open instance left - that it is either not correct to convert there, or that it is not converted due to current stream_open.cocci limitations. The script also does not convert files that should be valid to convert, but that currently have .llseek = noop_llseek or generic_file_llseek for unknown reason despite file being opened with nonseekable_open (e.g. drivers/input/mousedev.c) Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Yongzhi Pan <panyongzhi@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Juergen Gross <jgross@suse.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Tejun Heo <tj@kernel.org> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Cc: Nikolaus Rath <Nikolaus@rath.org> Cc: Han-Wen Nienhuys <hanwen@google.com> Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-04-03objtool: Add UACCESS validationPeter Zijlstra1-0/+3
It is important that UACCESS regions are as small as possible; furthermore the UACCESS state is not scheduled, so doing anything that might directly call into the scheduler will cause random code to be ran with UACCESS enabled. Teach objtool too track UACCESS state and warn about any CALL made while UACCESS is enabled. This very much includes the __fentry__() and __preempt_schedule() calls. Note that exceptions _do_ save/restore the UACCESS state, and therefore they can drive preemption. This also means that all exception handlers must have an otherwise redundant UACCESS disable instruction; therefore ignore this warning for !STT_FUNC code (exception handlers are not normal functions). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03kbuild: add ability to generate BTF type info for vmlinuxAndrii Nakryiko1-1/+19
This patch adds new config option to trigger generation of BTF type information from DWARF debuginfo for vmlinux and kernel modules through pahole, which in turn relies on libbpf for btf_dedup() algorithm. The intent is to record compact type information of all types used inside kernel, including all the structs/unions/typedefs/etc. This enables BPF's compile-once-run-everywhere ([0]) approach, in which tracing programs that are inspecting kernel's internal data (e.g., struct task_struct) can be compiled on a system running some kernel version, but would be possible to run on other kernel versions (and configurations) without recompilation, even if the layout of structs changed and/or some of the fields were added, removed, or renamed. This is only possible if BPF loader can get kernel type info to adjust all the offsets correctly. This patch is a first time in this direction, making sure that BTF type info is part of Linux kernel image in non-loadable ELF section. BTF deduplication ([1]) algorithm typically provides 100x savings compared to DWARF data, so resulting .BTF section is not big as is typically about 2MB in size. [0] http://vger.kernel.org/lpc-bpf2018.html#session-2 [1] https://facebookmicrosites.github.io/bpf/blog/2018/11/14/btf-enhancement.html Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Alexei Starovoitov <ast@fb.com> Cc: Yonghong Song <yhs@fb.com> Cc: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-04-02kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree buildMasahiro Yamada6-6/+6
KBUILD_SRC was conventionally used for some different purposes: [1] To remember the source tree path [2] As a flag to check if sub-make is already done [3] As a flag to check if Kbuild runs out of tree For [1], we do not need to remember it because the top Makefile can compute it by $(realpath $(dir $(lastword $(MAKEFILE_LIST)))) [2] has been replaced with self-commenting 'sub_make_done'. For [3], we can distinguish in-tree/out-of-tree by comparing $(srctree) and '.' This commit converts [3] to prepare for the KBUILD_SRC removal. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-16 14:25:59 +0000