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2021-02-10bpf: Fix verifier jsgt branch analysis on max boundDaniel Borkmann
Fix incorrect is_branch{32,64}_taken() analysis for the jsgt case. The return code for both will tell the caller whether a given conditional jump is taken or not, e.g. 1 means branch will be taken [for the involved registers] and the goto target will be executed, 0 means branch will not be taken and instead we fall-through to the next insn, and last but not least a -1 denotes that it is not known at verification time whether a branch will be taken or not. Now while the jsgt has the branch-taken case correct with reg->s32_min_value > sval, the branch-not-taken case is off-by-one when testing for reg->s32_max_value < sval since the branch will also be taken for reg->s32_max_value == sval. The jgt branch analysis, for example, gets this right. Fixes: 3f50f132d840 ("bpf: Verifier, do explicit ALU32 bounds tracking") Fixes: 4f7b3e82589e ("bpf: improve verifier branch analysis") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-02-09tracing: Add a backward-compatibility check for synthetic event creationTom Zanussi
The synthetic event parsing rework now requires semicolons between synthetic event fields. That requirement breaks existing users who might already have used the old synthetic event command format, so this adds an inner loop that can parse more than one field, if present, between semicolons. For each field, parse_synth_field() checks in which version that field was introduced, using check_field_version(). The caller, __create_synth_event() can then use that version information to determine whether or not to enforce the requirement on the command as a whole. In the future, if/when new features are added, the requirement will be that any field/string containing the new feature must use semicolons, and the check_field_version() check can then check for those and enforce it. Using a version number allows this scheme to be extended if necessary. Link: https://lkml.kernel.org/r/74fcc500d561b40ce91c5ee94818c70c6b0c9330.1612208610.git.zanussi@kernel.org [ zanussi: added check_field_version() comment from rostedt@goodmis.org ] Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09tracing: Update synth command errorsTom Zanussi
Since array types are handled differently, errors referencing them also need to be handled differently. Add and use a new INVALID_ARRAY_SPEC error. Also add INVALID_CMD and INVALID_DYN_CMD to catch and display the correct form for badly-formed commands, which can also be used in place of CMD_INCOMPLETE, which is removed, and remove CMD_TOO_LONG, since it's no longer used. Link: https://lkml.kernel.org/r/b9dd434dc6458dcff11adc6ed616fe93a8794770.1612208610.git.zanussi@kernel.org Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09tracing: Rework synthetic event command parsingTom Zanussi
Now that command parsing has been delegated to the create functions and we're no longer constrained by argv_split(), we can modify the synthetic event command parser to better match the higher-level structure of the synthetic event commands, which is basically an event name followed by a set of semicolon-separated fields. Since we're also now passed the raw command, we can also save it directly and can get rid of save_cmdstr(). Link: https://lkml.kernel.org/r/cb9e2be92d992ce59f2b4f132264a5d467f3933f.1612208610.git.zanussi@kernel.org Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09tracing/dynevent: Delegate parsing to create functionMasami Hiramatsu
Delegate command parsing to each create function so that the command syntax can be customized. This requires changes to the kprobe/uprobe/synthetic event handling, which are also included here. Link: https://lkml.kernel.org/r/e488726f49cbdbc01568618f8680584306c4c79f.1612208610.git.zanussi@kernel.org Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> [ zanussi@kernel.org: added synthetic event modifications ] Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09kprobes: Warn if the kprobe is reregisteredMasami Hiramatsu
Warn if the kprobe is reregistered, since there must be a software bug (actively used resource must not be re-registered) and caller must be fixed. Link: https://lkml.kernel.org/r/161236436734.194052.4058506306336814476.stgit@devnote2 Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Ananth N Mavinakayanahalli <ananth@linux.ibm.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09tracepoints: Code clean upSteven Rostedt (VMware)
Restructure the code a bit to make it simpler, fix some formatting problems and add READ_ONCE/WRITE_ONCE to make sure there's no compiler load/store tearing to the variables that can be accessed across CPUs. Started with Mathieu Desnoyers's patch: Link: https://lore.kernel.org/lkml/20210203175741.20665-1-mathieu.desnoyers@efficios.com/ And will keep his signature, but I will take the responsibility of this being correct, and keep the authorship. Link: https://lkml.kernel.org/r/20210204143004.61126582@gandalf.local.home Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-09dma-mapping: remove the {alloc,free}_noncoherent methodsChristoph Hellwig
It turns out allowing non-contigous allocations here was a rather bad idea, as we'll now need to define ways to get the pages for mmaping or dma_buf sharing. Revert this change and stick to the original concept. A different API for the use case of non-contigous allocations will be added back later. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tomasz Figa <tfiga@chromium.org> Tested-by: Ricardo Ribalda <ribalda@chromium.org>:wq
2021-02-09irqdomain: Mark fwnodes when their irqdomain is added/removedSaravana Kannan
This allows fw_devlink to recognize irqdomain drivers that don't use the device-driver model to initialize the device. fw_devlink will use this information to make sure consumers of such irqdomain aren't indefinitely blocked from probing, waiting for the irqdomain device to appear and bind to a driver. Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/20210205222644.2357303-7-saravanak@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-08Merge tag 'trace-v5.11-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fix from Steven Rostedt: "Fix output of top level event tracing 'enable' file. When writing a tool for enabling events in the tracing system, an anomaly was discovered. The top level event 'enable' file would never show '1' when all events were enabled. The system and event 'enable' files worked as expected. The reason was because the top level event 'enable' file included the 'ftrace' tracer events, which are not controlled by the 'enable' file and would cause the output to be wrong. This appears to have been a bug since it was created" * tag 'trace-v5.11-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Do not count ftrace events in top level enable output
2021-02-08kdb: Make memory allocations more robustSumit Garg
Currently kdb uses in_interrupt() to determine whether its library code has been called from the kgdb trap handler or from a saner calling context such as driver init. This approach is broken because in_interrupt() alone isn't able to determine kgdb trap handler entry from normal task context. This can happen during normal use of basic features such as breakpoints and can also be trivially reproduced using: echo g > /proc/sysrq-trigger We can improve this by adding check for in_dbg_master() instead which explicitly determines if we are running in debugger context. Cc: stable@vger.kernel.org Signed-off-by: Sumit Garg <sumit.garg@linaro.org> Link: https://lore.kernel.org/r/1611313556-4004-1-git-send-email-sumit.garg@linaro.org Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2021-02-08module: remove EXPORT_UNUSED_SYMBOL*Christoph Hellwig
EXPORT_UNUSED_SYMBOL* is not actually used anywhere. Remove the unused functionality as we generally just remove unused code anyway. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08module: remove EXPORT_SYMBOL_GPL_FUTUREChristoph Hellwig
As far as I can tell this has never been used at all, and certainly not any time recently. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08module: move struct symsearch to module.cChristoph Hellwig
struct symsearch is only used inside of module.h, so move the definition out of module.h. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08module: pass struct find_symbol_args to find_symbolChristoph Hellwig
Simplify the calling convention by passing the find_symbol_args structure to find_symbol instead of initializing it inside the function. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08module: merge each_symbol_section into find_symbolChristoph Hellwig
each_symbol_section is only called by find_symbol, so merge the two functions. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08module: remove each_symbol_in_sectionChristoph Hellwig
each_symbol_in_section just contains a trivial loop over its arguments. Just open code the loop in the two callers. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08module: mark module_mutex staticChristoph Hellwig
Except for two lockdep asserts module_mutex is only used in module.c. Remove the two asserts given that the functions they are in are not exported and just called from the module code, and mark module_mutex static. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08kallsyms: only build {,module_}kallsyms_on_each_symbol when requiredChristoph Hellwig
kallsyms_on_each_symbol and module_kallsyms_on_each_symbol are only used by the livepatching code, so don't build them if livepatching is not enabled. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08kallsyms: refactor {,module_}kallsyms_on_each_symbolChristoph Hellwig
Require an explicit call to module_kallsyms_on_each_symbol to look for symbols in modules instead of the call from kallsyms_on_each_symbol, and acquire module_mutex inside of module_kallsyms_on_each_symbol instead of leaving that up to the caller. Note that this slightly changes the behavior for the livepatch code in that the symbols from vmlinux are not iterated anymore if objname is set, but that actually is the desired behavior in this case. Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08module: use RCU to synchronize find_moduleChristoph Hellwig
Allow for a RCU-sched critical section around find_module, following the lower level find_module_all helper, and switch the two callers outside of module.c to use such a RCU-sched critical section instead of module_mutex. Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08module: unexport find_module and module_mutexChristoph Hellwig
find_module is not used by modular code any more, and random driver code has no business calling it to start with. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-07Merge tag 'dma-mapping-5.11-2' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds
Pull dma-mapping fix from Christoph Hellwig: "Fix a 32 vs 64-bit padding issue in the new benchmark code (Barry Song)" * tag 'dma-mapping-5.11-2' of git://git.infradead.org/users/hch/dma-mapping: dma-mapping: benchmark: use u8 for reserved field in uAPI structure
2021-02-07Merge tag 'irq_urgent_for_v5.11_rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Borislav Petkov: - Prevent device managed IRQ allocation helpers from returning IRQ 0 - A fix for MSI activation of PCI endpoints with multiple MSIs * tag 'irq_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Prevent [devm_]irq_alloc_desc from returning irq 0 genirq/msi: Activate Multi-MSI early when MSI_FLAG_ACTIVATE_EARLY is set
2021-02-07Merge tag 'core_urgent_for_v5.11_rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull syscall entry fixes from Borislav Petkov: - For syscall user dispatch, separate prctl operation from syscall redirection range specification before the API has been made official in 5.11. - Ensure tasks using the generic syscall code do trap after returning from a syscall when single-stepping is requested. * tag 'core_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: entry: Use different define for selector variable in SUD entry: Ensure trap after single-step on system call return
2021-02-07Merge tag 'timers_urgent_for_v5.11_rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Borislav Petkov: "Two more timers-related fixes for v5.11: - Use a freezable workqueue for RTC sync because the sync can happen at any time and trigger suspend assertion checks in the i2c subsystem. - Correct a previous RTC validation change to check only bit 6 in register D because some Intel machines use bits 0-5" * tag 'timers_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ntp: Use freezable workqueue for RTC synchronization rtc: mc146818: Dont test for bit 0-5 in Register D
2021-02-06entry: Use different define for selector variable in SUDGabriel Krisman Bertazi
Michael Kerrisk suggested that, from an API perspective, it is a bad idea to share the PR_SYS_DISPATCH_ defines between the prctl operation and the selector variable. Therefore, define two new constants to be used by SUD's selector variable and update the corresponding documentation and test cases. While this changes the API syscall user dispatch has never been part of a Linux release, it will show up for the first time in 5.11. Suggested-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210205184321.2062251-1-krisman@collabora.com
2021-02-06entry: Ensure trap after single-step on system call returnGabriel Krisman Bertazi
Commit 299155244770 ("entry: Drop usage of TIF flags in the generic syscall code") introduced a bug on architectures using the generic syscall entry code, in which processes stopped by PTRACE_SYSCALL do not trap on syscall return after receiving a TIF_SINGLESTEP. The reason is that the meaning of TIF_SINGLESTEP flag is overloaded to cause the trap after a system call is executed, but since the above commit, the syscall call handler only checks for the SYSCALL_WORK flags on the exit work. Split the meaning of TIF_SINGLESTEP such that it only means single-step mode, and create a new type of SYSCALL_WORK to request a trap immediately after a syscall in single-step mode. In the current implementation, the SYSCALL_WORK flag shadows the TIF_SINGLESTEP flag for simplicity. Update x86 to flip this bit when a tracer enables single stepping. Fixes: 299155244770 ("entry: Drop usage of TIF flags in the generic syscall code") Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kyle Huey <me@kylehuey.com> Link: https://lore.kernel.org/r/87h7mtc9pr.fsf_-_@collabora.com
2021-02-05tracing: Do not create "enable" or "filter" files for ftrace event subsystemSteven Rostedt (VMware)
The ftrace event subsystem is only created for showing the format files of events created by the ftrace tracers, and are not trace events. The ftrace subsystem currently has both the "enable" and "filter" files that in other subsystems are used to enable/disable all events within the subsystem or set a filter for all the subsystem events. As ftrace subsystem events do not use enable or filter operations, these files are useless in the ftrace subsystem. Remove them. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-05tracing: Do not count ftrace events in top level enable outputSteven Rostedt (VMware)
The file /sys/kernel/tracing/events/enable is used to enable all events by echoing in "1", or disabling all events when echoing in "0". To know if all events are enabled, disabled, or some are enabled but not all of them, cating the file should show either "1" (all enabled), "0" (all disabled), or "X" (some enabled but not all of them). This works the same as the "enable" files in the individule system directories (like tracing/events/sched/enable). But when all events are enabled, the top level "enable" file shows "X". The reason is that its checking the "ftrace" events, which are special events that only exist for their format files. These include the format for the function tracer events, that are enabled when the function tracer is enabled, but not by the "enable" file. The check includes these events, which will always be disabled, and even though all true events are enabled, the top level "enable" file will show "X" instead of "1". To fix this, have the check test the event's flags to see if it has the "IGNORE_ENABLE" flag set, and if so, not test it. Cc: stable@vger.kernel.org Fixes: 553552ce1796c ("tracing: Combine event filter_active and enable into single flags field") Reported-by: "Yordan Karadzhov (VMware)" <y.karadz@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-05init/gcov: allow CONFIG_CONSTRUCTORS on UML to fix module gcovJohannes Berg
On ARCH=um, loading a module doesn't result in its constructors getting called, which breaks module gcov since the debugfs files are never registered. On the other hand, in-kernel constructors have already been called by the dynamic linker, so we can't call them again. Get out of this conundrum by allowing CONFIG_CONSTRUCTORS to be selected, but avoiding the in-kernel constructor calls. Also remove the "if !UML" from GCOV selecting CONSTRUCTORS now, since we really do want CONSTRUCTORS, just not kernel binary ones. Link: https://lkml.kernel.org/r/20210120172041.c246a2cac2fb.I1358f584b76f1898373adfed77f4462c8705b736@changeid Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Jessica Yu <jeyu@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-05timens: Delete no-op time_ns_init()Alexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andrei Vagin <avagin@gmail.com> Link: https://lore.kernel.org/r/20201228215402.GA572900@localhost.localdomain
2021-02-05alarmtimer: Update kerneldocAlexandre Belloni
Update kerneldoc comments to reflect the actual arguments and return values of the documented functions. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210202013457.3482388-1-alexandre.belloni@bootlin.com
2021-02-05ntp: Use freezable workqueue for RTC synchronizationGeert Uytterhoeven
The bug fixed by commit e3fab2f3de081e98 ("ntp: Fix RTC synchronization on 32-bit platforms") revealed an underlying issue: RTC synchronization may happen anytime, even while the system is partially suspended. On systems where the RTC is connected to an I2C bus, the I2C bus controller may already or still be suspended, triggering a WARNING during suspend or resume from s2ram: WARNING: CPU: 0 PID: 124 at drivers/i2c/i2c-core.h:54 __i2c_transfer+0x634/0x680 i2c i2c-6: Transfer while suspended [...] Workqueue: events_power_efficient sync_hw_clock [...] (__i2c_transfer) (i2c_transfer) (regmap_i2c_read) ... (da9063_rtc_set_time) (rtc_set_time) (sync_hw_clock) (process_one_work) Fix this race condition by using the freezable instead of the normal power-efficient workqueue. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Rafael J. Wysocki <rafael@kernel.org> Link: https://lore.kernel.org/r/20210125143039.1051912-1-geert+renesas@glider.be
2021-02-05locking/lockdep: Avoid unmatched unlockPeter Zijlstra
Commit f6f48e180404 ("lockdep: Teach lockdep about "USED" <- "IN-NMI" inversions") overlooked that print_usage_bug() releases the graph_lock and called it without the graph lock held. Fixes: f6f48e180404 ("lockdep: Teach lockdep about "USED" <- "IN-NMI" inversions") Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Waiman Long <longman@redhat.com> Link: https://lkml.kernel.org/r/YBfkuyIfB1+VRxXP@hirez.programming.kicks-ass.net
2021-02-05dma-mapping: benchmark: pretend DMA is transmittingBarry Song
In a real dma mapping user case, after dma_map is done, data will be transmit. Thus, in multi-threaded user scenario, IOMMU contention should not be that severe. For example, if users enable multiple threads to send network packets through 1G/10G/100Gbps NIC, usually the steps will be: map -> transmission -> unmap. Transmission delay reduces the contention of IOMMU. Here a delay is added to simulate the transmission between map and unmap so that the tested result could be more accurate for TX and simple RX. A typical TX transmission for NIC would be like: map -> TX -> unmap since the socket buffers come from OS. Simple RX model eg. disk driver, is also map -> RX -> unmap, but real RX model in a NIC could be more complicated considering packets can come spontaneously and many drivers are using pre-mapped buffers pool. This is in the TBD list. Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-02-05dma-mapping: benchmark: use u8 for reserved field in uAPI structureBarry Song
The original code put five u32 before a u64 expansion[10] array. Five is odd, this will cause trouble in the extension of the structure by adding new features. This patch moves to use u8 for reserved field to avoid future alignment risk. Meanwhile, it also clears the memory of struct map_benchmark in tools, otherwise, if users use old version to run on newer kernel, the random expansion value will cause side effect on newer kernel. Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-02-04bpf: Refactor BPF_PSEUDO_CALL checking as a helper functionYonghong Song
There is no functionality change. This refactoring intends to facilitate next patch change with BPF_PSEUDO_FUNC. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210204234827.1628953-1-yhs@fb.com
2021-02-04bpf: Allow usage of BPF ringbuffer in sleepable programsKP Singh
The BPF ringbuffer map is pre-allocated and the implementation logic does not rely on disabling preemption or per-cpu data structures. Using the BPF ringbuffer sleepable LSM and tracing programs does not trigger any warnings with DEBUG_ATOMIC_SLEEP, DEBUG_PREEMPT, PROVE_RCU and PROVE_LOCKING and LOCKDEP enabled. This allows helpers like bpf_copy_from_user and bpf_ima_inode_hash to write to the BPF ring buffer from sleepable BPF programs. Signed-off-by: KP Singh <kpsingh@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210204193622.3367275-2-kpsingh@kernel.org
2021-02-04kdb: kdb_support: Fix debugging information problemStephen Zhang
There are several common patterns. 0: kdb_printf("...",...); which is the normal one. 1: kdb_printf("%s: "...,__func__,...) We could improve '1' to this : #define kdb_func_printf(format, args...) \ kdb_printf("%s: " format, __func__, ## args) 2: if(KDB_DEBUG(AR)) kdb_printf("%s "...,__func__,...); We could improve '2' to this : #define kdb_dbg_printf(mask, format, args...) \ do { \ if (KDB_DEBUG(mask)) \ kdb_func_printf(format, ## args); \ } while (0) In addition, we changed the format code of size_t to %zu. Signed-off-by: Stephen Zhang <stephenzhangzsd@gmail.com> Link: https://lore.kernel.org/r/1612440429-6391-1-git-send-email-stephenzhangzsd@gmail.com Reviewed-by: Douglas Anderson <dianders@chromium.org> [daniel.thompson@linaro.org: Minor typo and line length fixes in the patch description] Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2021-02-04kernel: debug: fix typo issuewengjianfeng
change 'regster' to 'register'. Signed-off-by: wengjianfeng <wengjianfeng@yulong.com> Link: https://lore.kernel.org/r/20210203081034.9004-1-samirweng1979@163.com Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2021-02-04kgdb: rectify kernel-doc for kgdb_unregister_io_module()Lukas Bulwahn
The command 'find ./kernel/debug/ | xargs ./scripts/kernel-doc -none' reported a typo in the kernel-doc of kgdb_unregister_io_module(). Rectify the kernel-doc, such that no issues remain for ./kernel/debug/. Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Link: https://lore.kernel.org/r/20210125144847.21896-1-lukas.bulwahn@gmail.com Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2021-02-04sched: Add cond_resched_rwlockBen Gardon
Safely rescheduling while holding a spin lock is essential for keeping long running kernel operations running smoothly. Add the facility to cond_resched rwlocks. CC: Ingo Molnar <mingo@redhat.com> CC: Will Deacon <will@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Davidlohr Bueso <dbueso@suse.de> Acked-by: Waiman Long <longman@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20210202185734.1680553-9-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-03bpf: Check for integer overflow when using roundup_pow_of_two()Bui Quang Minh
On 32-bit architecture, roundup_pow_of_two() can return 0 when the argument has upper most bit set due to resulting 1UL << 32. Add a check for this case. Fixes: d5a3b1f69186 ("bpf: introduce BPF_MAP_TYPE_STACK_TRACE") Signed-off-by: Bui Quang Minh <minhquangbui99@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20210127063653.3576-1-minhquangbui99@gmail.com
2021-02-03Merge tag 'trace-v5.11-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: - Initialize tracing-graph-pause at task creation, not start of function tracing, to avoid corrupting the pause counter. - Set "pause-on-trace" for latency tracers as that option breaks their output (regression). - Fix the wrong error return for setting kretprobes on future modules (before they are loaded). - Fix re-registering the same kretprobe. - Add missing value check for added RCU variable reload. * tag 'trace-v5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracepoint: Fix race between tracing and removing tracepoint kretprobe: Avoid re-registration of the same kretprobe earlier tracing/kprobe: Fix to support kretprobe events on unloaded modules tracing: Use pause-on-trace with the latency tracers fgraph: Initialize tracing_graph_pause at task creation
2021-02-03bpf: Unbreak BPF_PROG_TYPE_KPROBE when kprobe is called via do_int3Alexei Starovoitov
The commit 0d00449c7a28 ("x86: Replace ist_enter() with nmi_enter()") converted do_int3 handler to be "NMI-like". That made old if (in_nmi()) check abort execution of bpf programs attached to kprobe when kprobe is firing via int3 (For example when kprobe is placed in the middle of the function). Remove the check to restore user visible behavior. Fixes: 0d00449c7a28 ("x86: Replace ist_enter() with nmi_enter()") Reported-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Link: https://lore.kernel.org/bpf/20210203070636.70926-1-alexei.starovoitov@gmail.com
2021-02-02bpf: Propagate stack bounds to registers in atomics w/ BPF_FETCHBrendan Jackman
When BPF_FETCH is set, atomic instructions load a value from memory into a register. The current verifier code first checks via check_mem_access whether we can access the memory, and then checks via check_reg_arg whether we can write into the register. For loads, check_reg_arg has the side-effect of marking the register's value as unkonwn, and check_mem_access has the side effect of propagating bounds from memory to the register. This currently only takes effect for stack memory. Therefore with the current order, bounds information is thrown away, but by simply reversing the order of check_reg_arg vs. check_mem_access, we can instead propagate bounds smartly. A simple test is added with an infinite loop that can only be proved unreachable if this propagation is present. This is implemented both with C and directly in test_verifier using assembly. Suggested-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210202135002.4024825-1-jackmanb@google.com
2021-02-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-02kernel: trace: preemptirq_delay_test: add cpu affinitySong Chen
The kernel thread executing test can run on any cpu, which might be different cpu latency tracer is running on, as a result, the big latency caused by preemptirq delay test can't be detected. Therefore, the argument cpu_affinity is added to be passed to test, ensure it's running on the same cpu with latency tracer. e.g. cyclictest -p 90 -m -c 0 -i 1000 -a 3 modprobe preemptirq_delay_test test_mode=preempt delay=500 \ burst_size=3 cpu_affinity=3 Link: https://lkml.kernel.org/r/1611797713-20965-1-git-send-email-chensong_2000@189.cn Signed-off-by: Song Chen <chensong_2000@189.cn> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-02-02tracepoint: Do not fail unregistering a probe due to memory failureSteven Rostedt (VMware)
The list of tracepoint callbacks is managed by an array that is protected by RCU. To update this array, a new array is allocated, the updates are copied over to the new array, and then the list of functions for the tracepoint is switched over to the new array. After a completion of an RCU grace period, the old array is freed. This process happens for both adding a callback as well as removing one. But on removing a callback, if the new array fails to be allocated, the callback is not removed, and may be used after it is freed by the clients of the tracepoint. There's really no reason to fail if the allocation for a new array fails when removing a function. Instead, the function can simply be replaced by a stub function that could be cleaned up on the next modification of the array. That is, instead of calling the function registered to the tracepoint, it would call a stub function in its place. Link: https://lore.kernel.org/r/20201115055256.65625-1-mmullins@mmlx.us Link: https://lore.kernel.org/r/20201116175107.02db396d@gandalf.local.home Link: https://lore.kernel.org/r/20201117211836.54acaef2@oasis.local.home Link: https://lkml.kernel.org/r/20201118093405.7a6d2290@gandalf.local.home [ Note, this version does use undefined compiler behavior (assuming that a stub function with no parameters or return, can be called by a location that thinks it has parameters but still no return value. Static calls do the same thing, so this trick is not without precedent. There's another solution that uses RCU tricks and is more complex, but can be an alternative if this solution becomes an issue. Link: https://lore.kernel.org/lkml/20210127170721.58bce7cc@gandalf.local.home/ ] Cc: Peter Zijlstra <peterz@infradead.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Song Liu <songliubraving@fb.com> Cc: Yonghong Song <yhs@fb.com> Cc: Andrii Nakryiko <andriin@fb.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: KP Singh <kpsingh@chromium.org> Cc: netdev <netdev@vger.kernel.org> Cc: bpf <bpf@vger.kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Florian Weimer <fw@deneb.enyo.de> Fixes: 97e1c18e8d17b ("tracing: Kernel Tracepoints") Reported-by: syzbot+83aa762ef23b6f0d1991@syzkaller.appspotmail.com Reported-by: syzbot+d29e58bb557324e55e5e@syzkaller.appspotmail.com Reported-by: Matt Mullins <mmullins@mmlx.us> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Tested-by: Matt Mullins <mmullins@mmlx.us>