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2021-01-18module: Ignore _GLOBAL_OFFSET_TABLE_ when warning for undefined symbolsFangrui Song
clang-12 -fno-pic (since https://github.com/llvm/llvm-project/commit/a084c0388e2a59b9556f2de0083333232da3f1d6) can emit `call __stack_chk_fail@PLT` instead of `call __stack_chk_fail` on x86. The two forms should have identical behaviors on x86-64 but the former causes GNU as<2.37 to produce an unreferenced undefined symbol _GLOBAL_OFFSET_TABLE_. (On x86-32, there is an R_386_PC32 vs R_386_PLT32 difference but the linker behavior is identical as far as Linux kernel is concerned.) Simply ignore _GLOBAL_OFFSET_TABLE_ for now, like what scripts/mod/modpost.c:ignore_undef_symbol does. This also fixes the problem for gcc/clang -fpie and -fpic, which may emit `call foo@PLT` for external function calls on x86. Note: ld -z defs and dynamic loaders do not error for unreferenced undefined symbols so the module loader is reading too much. If we ever need to ignore more symbols, the code should be refactored to ignore unreferenced symbols. Cc: <stable@vger.kernel.org> Link: https://github.com/ClangBuiltLinux/linux/issues/1250 Link: https://sourceware.org/bugzilla/show_bug.cgi?id=27178 Reported-by: Marco Elver <elver@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Marco Elver <elver@google.com> Signed-off-by: Fangrui Song <maskray@google.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-01-15Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski
Daniel Borkmann says: ==================== pull-request: bpf-next 2021-01-16 1) Extend atomic operations to the BPF instruction set along with x86-64 JIT support, that is, atomic{,64}_{xchg,cmpxchg,fetch_{add,and,or,xor}}, from Brendan Jackman. 2) Add support for using kernel module global variables (__ksym externs in BPF programs) retrieved via module's BTF, from Andrii Nakryiko. 3) Generalize BPF stackmap's buildid retrieval and add support to have buildid stored in mmap2 event for perf, from Jiri Olsa. 4) Various fixes for cross-building BPF sefltests out-of-tree which then will unblock wider automated testing on ARM hardware, from Jean-Philippe Brucker. 5) Allow to retrieve SOL_SOCKET opts from sock_addr progs, from Daniel Borkmann. 6) Clean up driver's XDP buffer init and split into two helpers to init per- descriptor and non-changing fields during processing, from Lorenzo Bianconi. 7) Minor misc improvements to libbpf & bpftool, from Ian Rogers. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (41 commits) perf: Add build id data in mmap2 event bpf: Add size arg to build_id_parse function bpf: Move stack_map_get_build_id into lib bpf: Document new atomic instructions bpf: Add tests for new BPF atomic operations bpf: Add bitwise atomic instructions bpf: Pull out a macro for interpreting atomic ALU operations bpf: Add instructions for atomic_[cmp]xchg bpf: Add BPF_FETCH field / create atomic_fetch_add instruction bpf: Move BPF_STX reserved field check into BPF_STX verifier code bpf: Rename BPF_XADD and prepare to encode other atomics in .imm bpf: x86: Factor out a lookup table for some ALU opcodes bpf: x86: Factor out emission of REX byte bpf: x86: Factor out emission of ModR/M for *(reg + off) tools/bpftool: Add -Wall when building BPF programs bpf, libbpf: Avoid unused function warning on bpf_tail_call_static selftests/bpf: Install btf_dump test cases selftests/bpf: Fix installation of urandom_read selftests/bpf: Move generated test files to $(TEST_GEN_FILES) selftests/bpf: Fix out-of-tree build ... ==================== Link: https://lore.kernel.org/r/20210116012922.17823-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-15Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfJakub Kicinski
Daniel Borkmann says: ==================== pull-request: bpf 2021-01-16 1) Fix a double bpf_prog_put() for BPF_PROG_{TYPE_EXT,TYPE_TRACING} types in link creation's error path causing a refcount underflow, from Jiri Olsa. 2) Fix BTF validation errors for the case where kernel modules don't declare any new types and end up with an empty BTF, from Andrii Nakryiko. 3) Fix BPF local storage helpers to first check their {task,inode} owners for being NULL before access, from KP Singh. 4) Fix a memory leak in BPF setsockopt handling for the case where optlen is zero and thus temporary optval buffer should be freed, from Stanislav Fomichev. 5) Fix a syzbot memory allocation splat in BPF_PROG_TEST_RUN infra for raw_tracepoint caused by too big ctx_size_in, from Song Liu. 6) Fix LLVM code generation issues with verifier where PTR_TO_MEM{,_OR_NULL} registers were spilled to stack but not recognized, from Gilad Reti. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: MAINTAINERS: Update my email address selftests/bpf: Add verifier test for PTR_TO_MEM spill bpf: Support PTR_TO_MEM{,_OR_NULL} register spilling bpf: Reject too big ctx_size_in for raw_tp test run libbpf: Allow loading empty BTFs bpf: Allow empty module BTFs bpf: Don't leak memory in bpf getsockopt when optlen == 0 bpf: Update local storage test to check handling of null ptrs bpf: Fix typo in bpf_inode_storage.c bpf: Local storage helpers should check nullness of owner ptr passed bpf: Prevent double bpf_prog_put call from bpf_tracing_prog_attach ==================== Link: https://lore.kernel.org/r/20210116002025.15706-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-15cpuset: fix typos in commentsAubrey Li
Change hierachy to hierarchy and congifured to configured, no functionality changed. Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-01-15cgroup: cgroup.{procs,threads} factor out common partsMichal Koutný
The functions cgroup_threads_write and cgroup_procs_write are almost identical. In order to reduce duplication, factor out the common code in similar fashion we already do for other threadgroup/task functions. No functional changes are intended. Suggested-by: Hao Lee <haolee.swjtu@gmail.com> Signed-off-by: Michal Koutný <mkoutny@suse.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-01-15cgroup-v1: add disabled controller check in cgroup1_parse_param()Chen Zhou
When mounting a cgroup hierarchy with disabled controller in cgroup v1, all available controllers will be attached. For example, boot with cgroup_no_v1=cpu or cgroup_disable=cpu, and then mount with "mount -t cgroup -ocpu cpu /sys/fs/cgroup/cpu", then all enabled controllers will be attached except cpu. Fix this by adding disabled controller check in cgroup1_parse_param(). If the specified controller is disabled, just return error with information "Disabled controller xx" rather than attaching all the other enabled controllers. Fixes: f5dfb5315d34 ("cgroup: take options parsing into ->parse_monolithic()") Signed-off-by: Chen Zhou <chenzhou10@huawei.com> Reviewed-by: Zefan Li <lizefan.x@bytedance.com> Reviewed-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-01-15audit: Remove leftover reference to the audit_taskletDavidlohr Bueso
This was replaced with a kauditd_wait kthread long ago, back in: b7d1125817c (AUDIT: Send netlink messages from a separate kernel thread) Update the stale comment. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-01-15printk: fix kmsg_dump_get_buffer length calulationsJohn Ogness
kmsg_dump_get_buffer() uses @syslog to determine if the syslog prefix should be written to the buffer. However, when calculating the maximum number of records that can fit into the buffer, it always counts the bytes from the syslog prefix. Use @syslog when calculating the maximum number of records that can fit into the buffer. Fixes: e2ae715d66bf ("kmsg - kmsg_dump() use iterator to receive log buffer content") Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20210113164413.1599-1-john.ogness@linutronix.de
2021-01-15printk: ringbuffer: fix line countingJohn Ogness
Counting text lines in a record simply involves counting the number of newline characters (+1). However, it is searching the full data block for newline characters, even though the text data can be (and often is) a subset of that area. Since the extra area in the data block was never initialized, the result is that extra newlines may be seen and counted. Restrict newline searching to the text data length. Fixes: b6cf8b3f3312 ("printk: add lockless ringbuffer") Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20210113144234.6545-1-john.ogness@linutronix.de
2021-01-14perf: Add build id data in mmap2 eventJiri Olsa
Adding support to carry build id data in mmap2 event. The build id data replaces maj/min/ino/ino_generation fields, which are also used to identify map's binary, so it's ok to replace them with build id data: union { struct { u32 maj; u32 min; u64 ino; u64 ino_generation; }; struct { u8 build_id_size; u8 __reserved_1; u16 __reserved_2; u8 build_id[20]; }; }; Replaced maj/min/ino/ino_generation fields give us size of 24 bytes. We use 20 bytes for build id data, 1 byte for size and rest is unused. There's new misc bit for mmap2 to signal there's build id data in it: #define PERF_RECORD_MISC_MMAP_BUILD_ID (1 << 14) Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/bpf/20210114134044.1418404-4-jolsa@kernel.org
2021-01-14bpf: Add size arg to build_id_parse functionJiri Olsa
It's possible to have other build id types (other than default SHA1). Currently there's also ld support for MD5 build id. Adding size argument to build_id_parse function, that returns (if defined) size of the parsed build id, so we can recognize the build id type. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210114134044.1418404-3-jolsa@kernel.org
2021-01-14bpf: Move stack_map_get_build_id into libJiri Olsa
Moving stack_map_get_build_id into lib with declaration in linux/buildid.h header: int build_id_parse(struct vm_area_struct *vma, unsigned char *build_id); This function returns build id for given struct vm_area_struct. There is no functional change to stack_map_get_build_id function. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20210114134044.1418404-2-jolsa@kernel.org
2021-01-14bpf: Add bitwise atomic instructionsBrendan Jackman
This adds instructions for atomic[64]_[fetch_]and atomic[64]_[fetch_]or atomic[64]_[fetch_]xor All these operations are isomorphic enough to implement with the same verifier, interpreter, and x86 JIT code, hence being a single commit. The main interesting thing here is that x86 doesn't directly support the fetch_ version these operations, so we need to generate a CMPXCHG loop in the JIT. This requires the use of two temporary registers, IIUC it's safe to use BPF_REG_AX and x86's AUX_REG for this purpose. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-10-jackmanb@google.com
2021-01-14bpf: Pull out a macro for interpreting atomic ALU operationsBrendan Jackman
Since the atomic operations that are added in subsequent commits are all isomorphic with BPF_ADD, pull out a macro to avoid the interpreter becoming dominated by lines of atomic-related code. Note that this sacrificies interpreter performance (combining STX_ATOMIC_W and STX_ATOMIC_DW into single switch case means that we need an extra conditional branch to differentiate them) in favour of compact and (relatively!) simple C code. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-9-jackmanb@google.com
2021-01-14bpf: Add instructions for atomic_[cmp]xchgBrendan Jackman
This adds two atomic opcodes, both of which include the BPF_FETCH flag. XCHG without the BPF_FETCH flag would naturally encode atomic_set. This is not supported because it would be of limited value to userspace (it doesn't imply any barriers). CMPXCHG without BPF_FETCH woulud be an atomic compare-and-write. We don't have such an operation in the kernel so it isn't provided to BPF either. There are two significant design decisions made for the CMPXCHG instruction: - To solve the issue that this operation fundamentally has 3 operands, but we only have two register fields. Therefore the operand we compare against (the kernel's API calls it 'old') is hard-coded to be R0. x86 has similar design (and A64 doesn't have this problem). A potential alternative might be to encode the other operand's register number in the immediate field. - The kernel's atomic_cmpxchg returns the old value, while the C11 userspace APIs return a boolean indicating the comparison result. Which should BPF do? A64 returns the old value. x86 returns the old value in the hard-coded register (and also sets a flag). That means return-old-value is easier to JIT, so that's what we use. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-8-jackmanb@google.com
2021-01-14bpf: Add BPF_FETCH field / create atomic_fetch_add instructionBrendan Jackman
The BPF_FETCH field can be set in bpf_insn.imm, for BPF_ATOMIC instructions, in order to have the previous value of the atomically-modified memory location loaded into the src register after an atomic op is carried out. Suggested-by: Yonghong Song <yhs@fb.com> Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-7-jackmanb@google.com
2021-01-14bpf: Move BPF_STX reserved field check into BPF_STX verifier codeBrendan Jackman
I can't find a reason why this code is in resolve_pseudo_ldimm64; since I'll be modifying it in a subsequent commit, tidy it up. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-6-jackmanb@google.com
2021-01-14bpf: Rename BPF_XADD and prepare to encode other atomics in .immBrendan Jackman
A subsequent patch will add additional atomic operations. These new operations will use the same opcode field as the existing XADD, with the immediate discriminating different operations. In preparation, rename the instruction mode BPF_ATOMIC and start calling the zero immediate BPF_ADD. This is possible (doesn't break existing valid BPF progs) because the immediate field is currently reserved MBZ and BPF_ADD is zero. All uses are removed from the tree but the BPF_XADD definition is kept around to avoid breaking builds for people including kernel headers. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Björn Töpel <bjorn.topel@gmail.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-5-jackmanb@google.com
2021-01-14locking/lockdep: Exclude local_lock_t from IRQ inversionsBoqun Feng
The purpose of local_lock_t is to abstract: preempt_disable() / local_bh_disable() / local_irq_disable(). These are the traditional means of gaining access to per-cpu data, but are fundamentally non-preemptible. local_lock_t provides a per-cpu lock, that on !PREEMPT_RT reduces to no-ops, just like regular spinlocks do on UP. This gives rise to: CPU0 CPU1 local_lock(B) spin_lock_irq(A) <IRQ> spin_lock(A) local_lock(B) Where lockdep then figures things will lock up; which would be true if B were any other kind of lock. However this is a false positive, no such deadlock actually exists. For !RT the above local_lock(B) is preempt_disable(), and there's obviously no deadlock; alternatively, CPU0's B != CPU1's B. For RT the argument is that since local_lock() nests inside spin_lock(), it cannot be used in hardirq context, and therefore CPU0 cannot in fact happen. Even though B is a real lock, it is a preemptible lock and any threaded-irq would simply schedule out and let the preempted task (which holds B) continue such that the task on CPU1 can make progress, after which the threaded-irq resumes and can finish. This means that we can never form an IRQ inversion on a local_lock dependency, so terminate the graph walk when looking for IRQ inversions when we encounter one. One consequence is that (for LOCKDEP_SMALL) when we look for redundant dependencies, A -> B is not redundant in the presence of A -> L -> B. Signed-off-by: Boqun Feng <boqun.feng@gmail.com> [peterz: Changelog] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-01-14locking/lockdep: Clean up check_redundant() a bitPeter Zijlstra
In preparation for adding an TRACE_IRQFLAGS dependent skip function to check_redundant(), move it below the TRACE_IRQFLAGS #ifdef. While there, provide a stub function to reduce #ifdef usage. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-01-14locking/lockdep: Add a skip() function to __bfs()Boqun Feng
Some __bfs() walks will have additional iteration constraints (beyond the path being strong). Provide an additional function to allow terminating graph walks. Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-01-14locking/lockdep: Mark local_lock_tPeter Zijlstra
The local_lock_t's are special, because they cannot form IRQ inversions, make sure we can tell them apart from the rest of the locks. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-01-14sched: Use task_current() instead of 'rq->curr == p'Hui Su
Use the task_current() function where appropriate. No functional change. Signed-off-by: Hui Su <sh_def@163.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lkml.kernel.org/r/20201030173223.GA52339@rlk
2021-01-14sched/fair: Reduce cases for active balanceVincent Guittot
Active balance is triggered for a number of voluntary cases like misfit or pinned tasks cases but also after that a number of load balance attempts failed to migrate a task. There is no need to use active load balance when the group is overloaded because an overloaded state means that there is at least one waiting task. Nevertheless, the waiting task is not selected and detached until the threshold becomes higher than its load. This threshold increases with the number of failed lb (see the condition if ((load >> env->sd->nr_balance_failed) > env->imbalance) in detach_tasks()) and the waiting task will end up to be selected after a number of attempts. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Acked-by: Mel Gorman <mgorman@suse.de> Link: https://lkml.kernel.org/r/20210107103325.30851-4-vincent.guittot@linaro.org
2021-01-14sched/fair: Don't set LBF_ALL_PINNED unnecessarilyVincent Guittot
Setting LBF_ALL_PINNED during active load balance is only valid when there is only 1 running task on the rq otherwise this ends up increasing the balance interval whereas other tasks could migrate after the next interval once they become cache-cold as an example. LBF_ALL_PINNED flag is now always set it by default. It is then cleared when we find one task that can be pulled when calling detach_tasks() or during active migration. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Acked-by: Mel Gorman <mgorman@suse.de> Link: https://lkml.kernel.org/r/20210107103325.30851-3-vincent.guittot@linaro.org
2021-01-14sched/fair: Skip idle cfs_rqVincent Guittot
Don't waste time checking whether an idle cfs_rq could be the busiest queue. Furthermore, this can end up selecting a cfs_rq with a high load but being idle in case of migrate_load. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Acked-by: Mel Gorman <mgorman@suse.de> Link: https://lkml.kernel.org/r/20210107103325.30851-2-vincent.guittot@linaro.org
2021-01-14sched/fair: Avoid stale CPU util_est value for schedutil in task dequeueXuewen Yan
CPU (root cfs_rq) estimated utilization (util_est) is currently used in dequeue_task_fair() to drive frequency selection before it is updated. with: CPU_util : rq->cfs.avg.util_avg CPU_util_est : rq->cfs.avg.util_est CPU_utilization : max(CPU_util, CPU_util_est) task_util : p->se.avg.util_avg task_util_est : p->se.avg.util_est dequeue_task_fair(): /* (1) CPU_util and task_util update + inform schedutil about CPU_utilization changes */ for_each_sched_entity() /* 2 loops */ (dequeue_entity() ->) update_load_avg() -> cfs_rq_util_change() -> cpufreq_update_util() ->...-> sugov_update_[shared\|single] -> sugov_get_util() -> cpu_util_cfs() /* (2) CPU_util_est and task_util_est update */ util_est_dequeue() cpu_util_cfs() uses CPU_utilization which could lead to a false (too high) utilization value for schedutil in task ramp-down or ramp-up scenarios during task dequeue. To mitigate the issue split the util_est update (2) into: (A) CPU_util_est update in util_est_dequeue() (B) task_util_est update in util_est_update() Place (A) before (1) and keep (B) where (2) is. The latter is necessary since (B) relies on task_util update in (1). Fixes: 7f65ea42eb00 ("sched/fair: Add util_est on top of PELT") Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lkml.kernel.org/r/1608283672-18240-1-git-send-email-xuewen.yan94@gmail.com
2021-01-14sched: Prevent raising SCHED_SOFTIRQ when CPU is !activeAnna-Maria Behnsen
SCHED_SOFTIRQ is raised to trigger periodic load balancing. When CPU is not active, CPU should not participate in load balancing. The scheduler uses nohz.idle_cpus_mask to keep track of the CPUs which can do idle load balancing. When bringing a CPU up the CPU is added to the mask when it reaches the active state, but on teardown the CPU stays in the mask until it goes offline and invokes sched_cpu_dying(). When SCHED_SOFTIRQ is raised on a !active CPU, there might be a pending softirq when stopping the tick which triggers a warning in NOHZ code. The SCHED_SOFTIRQ can also be raised by the scheduler tick which has the same issue. Therefore remove the CPU from nohz.idle_cpus_mask when it is marked inactive and also prevent the scheduler_tick() from raising SCHED_SOFTIRQ after this point. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lkml.kernel.org/r/20201215104400.9435-1-anna-maria@linutronix.de
2021-01-14sched/core: Rename schedutil_cpu_util() and allow rest of the kernel to use itViresh Kumar
There is nothing schedutil specific in schedutil_cpu_util(), rename it to effective_cpu_util(). Also create and expose another wrapper sched_cpu_util() which can be used by other parts of the kernel, like thermal core (that will be done in a later commit). Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lkml.kernel.org/r/db011961fb3bb8bef1c0eda5cd64564637d3ef31.1607400596.git.viresh.kumar@linaro.org
2021-01-14sched/core: Move schedutil_cpu_util() to core.cViresh Kumar
There is nothing schedutil specific in schedutil_cpu_util(), move it to core.c and define it only for CONFIG_SMP. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lkml.kernel.org/r/c921a362c78e1324f8ebc5aaa12f53e309c5a8a2.1607400596.git.viresh.kumar@linaro.org
2021-01-13bpf: Support PTR_TO_MEM{,_OR_NULL} register spillingGilad Reti
Add support for pointer to mem register spilling, to allow the verifier to track pointers to valid memory addresses. Such pointers are returned for example by a successful call of the bpf_ringbuf_reserve helper. The patch was partially contributed by CyberArk Software, Inc. Fixes: 457f44363a88 ("bpf: Implement BPF ring buffer and verifier support for it") Suggested-by: Yonghong Song <yhs@fb.com> Signed-off-by: Gilad Reti <gilad.reti@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: KP Singh <kpsingh@kernel.org> Link: https://lore.kernel.org/bpf/20210113053810.13518-1-gilad.reti@gmail.com
2021-01-13genirq: Export irq_check_status_bit()Thomas Gleixner
One of the users can be built modular: ERROR: modpost: "irq_check_status_bit" [drivers/perf/arm_spe_pmu.ko] undefined! Fixes: fdd029630434 ("genirq: Move status flag checks to core") Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201227192049.GA195845@roeck-us.net
2021-01-12bpf: Support BPF ksym variables in kernel modulesAndrii Nakryiko
Add support for directly accessing kernel module variables from BPF programs using special ldimm64 instructions. This functionality builds upon vmlinux ksym support, but extends ldimm64 with src_reg=BPF_PSEUDO_BTF_ID to allow specifying kernel module BTF's FD in insn[1].imm field. During BPF program load time, verifier will resolve FD to BTF object and will take reference on BTF object itself and, for module BTFs, corresponding module as well, to make sure it won't be unloaded from under running BPF program. The mechanism used is similar to how bpf_prog keeps track of used bpf_maps. One interesting change is also in how per-CPU variable is determined. The logic is to find .data..percpu data section in provided BTF, but both vmlinux and module each have their own .data..percpu entries in BTF. So for module's case, the search for DATASEC record needs to look at only module's added BTF types. This is implemented with custom search function. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Hao Luo <haoluo@google.com> Link: https://lore.kernel.org/bpf/20210112075520.4103414-6-andrii@kernel.org
2021-01-12bpf: Fix a verifier message for alloc size helper argBrendan Jackman
The error message here is misleading, the argument will be rejected unless it is a known constant. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210112123913.2016804-1-jackmanb@google.com
2021-01-12Merge tag 'irqchip-fixes-5.11-1' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent Pull irqchip fixes from Marc Zyngier: - Fix the MIPS CPU interrupt controller hierarchy - Simplify the PRUSS Kconfig entry - Eliminate trivial build warnings on the MIPS Loongson liointc - Fix error path in devm_platform_get_irqs_affinity() - Turn the BCM2836 IPI irq_eoi callback into irq_ack - Fix initialisation of on-stack msi_alloc_info - Cleanup spurious comma in irq-sl28cpld Link: https://lore.kernel.org/r/20210110110001.2328708-1-maz@kernel.org
2021-01-12ntp: Fix RTC synchronization on 32-bit platformsGeert Uytterhoeven
Due to an integer overflow, RTC synchronization now happens every 2s instead of the intended 11 minutes. Fix this by forcing 64-bit arithmetic for the sync period calculation. Annotate the other place which multiplies seconds for consistency as well. Fixes: c9e6189fb03123a7 ("ntp: Make the RTC synchronization more reliable") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210111103956.290378-1-geert+renesas@glider.be
2021-01-12timekeeping: Remove unused get_seconds()Chunguang Xu
The get_seconds() cleanup seems to have been completed, now it is time to delete the legacy interface to avoid misuse later. Signed-off-by: Chunguang Xu <brookxu@tencent.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/1606816351-26900-1-git-send-email-brookxu@tencent.com
2021-01-12bpf: Allow empty module BTFsAndrii Nakryiko
Some modules don't declare any new types and end up with an empty BTF, containing only valid BTF header and no types or strings sections. This currently causes BTF validation error. There is nothing wrong with such BTF, so fix the issue by allowing module BTFs with no types or strings. Fixes: 36e68442d1af ("bpf: Load and verify kernel module BTFs") Reported-by: Christopher William Snowhill <chris@kode54.net> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210110070341.1380086-1-andrii@kernel.org
2021-01-12locking/lockdep: Avoid noinstr warning for DEBUG_LOCKDEPPeter Zijlstra
vmlinux.o: warning: objtool: lock_is_held_type()+0x60: call to check_flags.part.0() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210106144017.652218215@infradead.org
2021-01-12locking/lockdep: Cure noinstr failPeter Zijlstra
When the compiler doesn't feel like inlining, it causes a noinstr fail: vmlinux.o: warning: objtool: lock_is_held_type()+0xb: call to lockdep_enabled() leaves .noinstr.text section Fixes: 4d004099a668 ("lockdep: Fix lockdep recursion") Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210106144017.592595176@infradead.org
2021-01-12bpf: Don't leak memory in bpf getsockopt when optlen == 0Stanislav Fomichev
optlen == 0 indicates that the kernel should ignore BPF buffer and use the original one from the user. We, however, forget to free the temporary buffer that we've allocated for BPF. Fixes: d8fe449a9c51 ("bpf: Don't return EINVAL from {get,set}sockopt when optlen > PAGE_SIZE") Reported-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20210112162829.775079-1-sdf@google.com
2021-01-12bpf: Fix typo in bpf_inode_storage.cKP Singh
Fix "gurranteed" -> "guaranteed" in bpf_inode_storage.c Suggested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: KP Singh <kpsingh@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210112075525.256820-4-kpsingh@kernel.org
2021-01-12bpf: Local storage helpers should check nullness of owner ptr passedKP Singh
The verifier allows ARG_PTR_TO_BTF_ID helper arguments to be NULL, so helper implementations need to check this before dereferencing them. This was already fixed for the socket storage helpers but not for task and inode. The issue can be reproduced by attaching an LSM program to inode_rename hook (called when moving files) which tries to get the inode of the new file without checking for its nullness and then trying to move an existing file to a new path: mv existing_file new_file_does_not_exist The report including the sample program and the steps for reproducing the bug: https://lore.kernel.org/bpf/CANaYP3HWkH91SN=wTNO9FL_2ztHfqcXKX38SSE-JJ2voh+vssw@mail.gmail.com Fixes: 4cf1bc1f1045 ("bpf: Implement task local storage") Fixes: 8ea636848aca ("bpf: Implement bpf_local_storage for inodes") Reported-by: Gilad Reti <gilad.reti@gmail.com> Signed-off-by: KP Singh <kpsingh@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210112075525.256820-3-kpsingh@kernel.org
2021-01-12resource: Move devmem revoke code to resource frameworkDaniel Vetter
We want all iomem mmaps to consistently revoke ptes when the kernel takes over and CONFIG_IO_STRICT_DEVMEM is enabled. This includes the pci bar mmaps available through procfs and sysfs, which currently do not revoke mappings. To prepare for this, move the code from the /dev/kmem driver to kernel/resource.c. During review Jason spotted that barriers are used somewhat inconsistently. Fix that up while we shuffle this code, since it doesn't have an actual impact at runtime. Otherwise no semantic and behavioural changes intended, just code extraction and adjusting comments and names. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kees Cook <keescook@chromium.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Hildenbrand <david@redhat.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20201127164131.2244124-11-daniel.vetter@ffwll.ch
2021-01-12bpf: Prevent double bpf_prog_put call from bpf_tracing_prog_attachJiri Olsa
The bpf_tracing_prog_attach error path calls bpf_prog_put on prog, which causes refcount underflow when it's called from link_create function. link_create prog = bpf_prog_get <-- get ... tracing_bpf_link_attach(prog.. bpf_tracing_prog_attach(prog.. out_put_prog: bpf_prog_put(prog); <-- put if (ret < 0) bpf_prog_put(prog); <-- put Removing bpf_prog_put call from bpf_tracing_prog_attach and making sure its callers call it instead. Fixes: 4a1e7c0c63e0 ("bpf: Support attaching freplace programs to multiple attach points") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210111191650.1241578-1-jolsa@kernel.org
2021-01-11Merge tag 'trace-v5.11-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fix from Steven Rostedt: "Blacklist properly on all archs. The code to blacklist notrace functions for kprobes was not using the right kconfig option, which caused some archs (powerpc) to possibly not blacklist them" * tag 'trace-v5.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/kprobes: Do the notrace functions check without kprobes on ftrace
2021-01-11tracing/kprobes: Do the notrace functions check without kprobes on ftraceMasami Hiramatsu
Enable the notrace function check on the architecture which doesn't support kprobes on ftrace but support dynamic ftrace. This notrace function check is not only for the kprobes on ftrace but also sw-breakpoint based kprobes. Thus there is no reason to limit this check for the arch which supports kprobes on ftrace. This also changes the dependency of Kconfig. Because kprobe event uses the function tracer's address list for identifying notrace function, if the CONFIG_DYNAMIC_FTRACE=n, it can not check whether the target function is notrace or not. Link: https://lkml.kernel.org/r/20210105065730.2634785-1-naveen.n.rao@linux.vnet.ibm.com Link: https://lkml.kernel.org/r/161007957862.114704.4512260007555399463.stgit@devnote2 Cc: stable@vger.kernel.org Fixes: 45408c4f92506 ("tracing: kprobes: Prohibit probing on notrace function") Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-01-11seccomp: Add missing return in non-void functionPaul Cercueil
We don't actually care about the value, since the kernel will panic before that; but a value should nonetheless be returned, otherwise the compiler will complain. Fixes: 8112c4f140fa ("seccomp: remove 2-phase API") Cc: stable@vger.kernel.org # 4.7+ Signed-off-by: Paul Cercueil <paul@crapouillou.net> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210111172839.640914-1-paul@crapouillou.net
2021-01-11kthread: remove comments about old _do_fork() helperYanfei Xu
The old _do_fork() helper has been removed in favor of kernel_clone(). Here correct some comments which still contain _do_fork() Link: https://lore.kernel.org/r/20210111104807.18022-1-yanfei.xu@windriver.com Cc: christian@brauner.io Cc: linux-kernel@vger.kernel.org Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-11Kernel: fork.c: Fix coding style: Do not use {} around single-line statementsAlexander Guril
Fixed two coding style issues in kernel/fork.c Do not use {} around single-line statements. Cc: linux-kernel@vger.kernel.org Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Alexander Guril <alexander.guril02@gmail.com> Link: https://lore.kernel.org/r/20201226114021.2589-1-alexander.guril02@gmail.com Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>