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2019-11-13ftrace: Add ftrace_find_direct_func()Steven Rostedt (VMware)
As function_graph tracer modifies the return address to insert a trampoline to trace the return of a function, it must be aware of a direct caller, as when it gets called, the function's return address may not be at on the stack where it expects. It may have to see if that return address points to the a direct caller and adjust if it is. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add register_ftrace_direct()Steven Rostedt (VMware)
Add the start of the functionality to allow other trampolines to use the ftrace mcount/fentry/nop location. This adds two new functions: register_ftrace_direct() and unregister_ftrace_direct() Both take two parameters: the first is the instruction address of where the mcount/fentry/nop exists, and the second is the trampoline to have that location called. This will handle cases where ftrace is already used on that same location, and will make it still work, where the registered direct called trampoline will get called after all the registered ftrace callers are handled. Currently, it will not allow for IP_MODIFY functions to be called at the same locations, which include some kprobes and live kernel patching. At this point, no architecture supports this. This is only the start of implementing the framework. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-08ftrace: Separate out functionality from ftrace_location_range()Steven Rostedt (VMware)
Create a new function called lookup_rec() from the functionality of ftrace_location_range(). The difference between lookup_rec() is that it returns the record that it finds, where as ftrace_location_range() returns only if it found a match or not. The lookup_rec() is static, and can be used for new functionality where ftrace needs to find a record of a specific address. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-08ftrace: Separate out the copying of a ftrace_hash from __ftrace_hash_move()Steven Rostedt (VMware)
Most of the functionality of __ftrace_hash_move() can be reused, but not all of it. That is, __ftrace_hash_move() is used to simply make a new hash from an existing one, using the same size as the original. Creating a dup_hash(), where we can specify a new size will be useful when we want to create a hash with a default size, or simply copy the old one. Signed-off-by: Steven Rostedt (VMWare) <rostedt@goodmis.org>
2019-11-04ftrace: Introduce PERMANENT ftrace_ops flagMiroslav Benes
Livepatch uses ftrace for redirection to new patched functions. It means that if ftrace is disabled, all live patched functions are disabled as well. Toggling global 'ftrace_enabled' sysctl thus affect it directly. It is not a problem per se, because only administrator can set sysctl values, but it still may be surprising. Introduce PERMANENT ftrace_ops flag to amend this. If the FTRACE_OPS_FL_PERMANENT is set on any ftrace ops, the tracing cannot be disabled by disabling ftrace_enabled. Equally, a callback with the flag set cannot be registered if ftrace_enabled is disabled. Link: http://lkml.kernel.org/r/20191016113316.13415-2-mbenes@suse.cz Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds
Pull networking fixes from David Miller: 1) Fix free/alloc races in batmanadv, from Sven Eckelmann. 2) Several leaks and other fixes in kTLS support of mlx5 driver, from Tariq Toukan. 3) BPF devmap_hash cost calculation can overflow on 32-bit, from Toke Høiland-Jørgensen. 4) Add an r8152 device ID, from Kazutoshi Noguchi. 5) Missing include in ipv6's addrconf.c, from Ben Dooks. 6) Use siphash in flow dissector, from Eric Dumazet. Attackers can easily infer the 32-bit secret otherwise etc. 7) Several netdevice nesting depth fixes from Taehee Yoo. 8) Fix several KCSAN reported errors, from Eric Dumazet. For example, when doing lockless skb_queue_empty() checks, and accessing sk_napi_id/sk_incoming_cpu lockless as well. 9) Fix jumbo packet handling in RXRPC, from David Howells. 10) Bump SOMAXCONN and tcp_max_syn_backlog values, from Eric Dumazet. 11) Fix DMA synchronization in gve driver, from Yangchun Fu. 12) Several bpf offload fixes, from Jakub Kicinski. 13) Fix sk_page_frag() recursion during memory reclaim, from Tejun Heo. 14) Fix ping latency during high traffic rates in hisilicon driver, from Jiangfent Xiao. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (146 commits) net: fix installing orphaned programs net: cls_bpf: fix NULL deref on offload filter removal selftests: bpf: Skip write only files in debugfs selftests: net: reuseport_dualstack: fix uninitalized parameter r8169: fix wrong PHY ID issue with RTL8168dp net: dsa: bcm_sf2: Fix IMP setup for port different than 8 net: phylink: Fix phylink_dbg() macro gve: Fixes DMA synchronization. inet: stop leaking jiffies on the wire ixgbe: Remove duplicate clear_bit() call Documentation: networking: device drivers: Remove stray asterisks e1000: fix memory leaks i40e: Fix receive buffer starvation for AF_XDP igb: Fix constant media auto sense switching when no cable is connected net: ethernet: arc: add the missed clk_disable_unprepare igb: Enable media autosense for the i350. igb/igc: Don't warn on fatal read failures when the device is removed tcp: increase tcp_max_syn_backlog max value net: increase SOMAXCONN to 4096 netdevsim: Fix use-after-free during device dismantle ...
2019-11-01Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "Fix two scheduler topology bugs/oversights on Juno r0 2+4 big.LITTLE systems" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/topology: Allow sched_asym_cpucapacity to be disabled sched/topology: Don't try to build empty sched domains
2019-10-29sched/topology: Allow sched_asym_cpucapacity to be disabledValentin Schneider
While the static key is correctly initialized as being disabled, it will remain forever enabled once turned on. This means that if we start with an asymmetric system and hotplug out enough CPUs to end up with an SMP system, the static key will remain set - which is obviously wrong. We should detect this and turn off things like misfit migration and capacity aware wakeups. As Quentin pointed out, having separate root domains makes this slightly trickier. We could have exclusive cpusets that create an SMP island - IOW, the domains within this root domain will not see any asymmetry. This means we can't just disable the key on domain destruction, we need to count how many asymmetric root domains we have. Consider the following example using Juno r0 which is 2+4 big.LITTLE, where two identical cpusets are created: they both span both big and LITTLE CPUs: asym0 asym1 [ ][ ] L L B L L B $ cgcreate -g cpuset:asym0 $ cgset -r cpuset.cpus=0,1,3 asym0 $ cgset -r cpuset.mems=0 asym0 $ cgset -r cpuset.cpu_exclusive=1 asym0 $ cgcreate -g cpuset:asym1 $ cgset -r cpuset.cpus=2,4,5 asym1 $ cgset -r cpuset.mems=0 asym1 $ cgset -r cpuset.cpu_exclusive=1 asym1 $ cgset -r cpuset.sched_load_balance=0 . (the CPU numbering may look odd because on the Juno LITTLEs are CPUs 0,3-5 and bigs are CPUs 1-2) If we make one of those SMP (IOW remove asymmetry) by e.g. hotplugging its big core, we would end up with an SMP cpuset and an asymmetric cpuset - the static key must remain set, because we still have one asymmetric root domain. With the above example, this could be done with: $ echo 0 > /sys/devices/system/cpu/cpu2/online Which would result in: asym0 asym1 [ ][ ] L L B L L When both SMP and asymmetric cpusets are present, all CPUs will observe sched_asym_cpucapacity being set (it is system-wide), but not all CPUs observe asymmetry in their sched domain hierarchy: per_cpu(sd_asym_cpucapacity, <any CPU in asym0>) == <some SD at DIE level> per_cpu(sd_asym_cpucapacity, <any CPU in asym1>) == NULL Change the simple key enablement to an increment, and decrement the key counter when destroying domains that cover asymmetric CPUs. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Dietmar.Eggemann@arm.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: hannes@cmpxchg.org Cc: lizefan@huawei.com Cc: morten.rasmussen@arm.com Cc: qperret@google.com Cc: tj@kernel.org Cc: vincent.guittot@linaro.org Fixes: df054e8445a4 ("sched/topology: Add static_key for asymmetric CPU capacity optimizations") Link: https://lkml.kernel.org/r/20191023153745.19515-3-valentin.schneider@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-29sched/topology: Don't try to build empty sched domainsValentin Schneider
Turns out hotplugging CPUs that are in exclusive cpusets can lead to the cpuset code feeding empty cpumasks to the sched domain rebuild machinery. This leads to the following splat: Internal error: Oops: 96000004 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 235 Comm: kworker/5:2 Not tainted 5.4.0-rc1-00005-g8d495477d62e #23 Hardware name: ARM Juno development board (r0) (DT) Workqueue: events cpuset_hotplug_workfn pstate: 60000005 (nZCv daif -PAN -UAO) pc : build_sched_domains (./include/linux/arch_topology.h:23 kernel/sched/topology.c:1898 kernel/sched/topology.c:1969) lr : build_sched_domains (kernel/sched/topology.c:1966) Call trace: build_sched_domains (./include/linux/arch_topology.h:23 kernel/sched/topology.c:1898 kernel/sched/topology.c:1969) partition_sched_domains_locked (kernel/sched/topology.c:2250) rebuild_sched_domains_locked (./include/linux/bitmap.h:370 ./include/linux/cpumask.h:538 kernel/cgroup/cpuset.c:955 kernel/cgroup/cpuset.c:978 kernel/cgroup/cpuset.c:1019) rebuild_sched_domains (kernel/cgroup/cpuset.c:1032) cpuset_hotplug_workfn (kernel/cgroup/cpuset.c:3205 (discriminator 2)) process_one_work (./arch/arm64/include/asm/jump_label.h:21 ./include/linux/jump_label.h:200 ./include/trace/events/workqueue.h:114 kernel/workqueue.c:2274) worker_thread (./include/linux/compiler.h:199 ./include/linux/list.h:268 kernel/workqueue.c:2416) kthread (kernel/kthread.c:255) ret_from_fork (arch/arm64/kernel/entry.S:1167) Code: f860dae2 912802d6 aa1603e1 12800000 (f8616853) The faulty line in question is: cap = arch_scale_cpu_capacity(cpumask_first(cpu_map)); and we're not checking the return value against nr_cpu_ids (we shouldn't have to!), which leads to the above. Prevent generate_sched_domains() from returning empty cpumasks, and add some assertion in build_sched_domains() to scream bloody murder if it happens again. The above splat was obtained on my Juno r0 with the following reproducer: $ cgcreate -g cpuset:asym $ cgset -r cpuset.cpus=0-3 asym $ cgset -r cpuset.mems=0 asym $ cgset -r cpuset.cpu_exclusive=1 asym $ cgcreate -g cpuset:smp $ cgset -r cpuset.cpus=4-5 smp $ cgset -r cpuset.mems=0 smp $ cgset -r cpuset.cpu_exclusive=1 smp $ cgset -r cpuset.sched_load_balance=0 . $ echo 0 > /sys/devices/system/cpu/cpu4/online $ echo 0 > /sys/devices/system/cpu/cpu5/online Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Dietmar.Eggemann@arm.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: hannes@cmpxchg.org Cc: lizefan@huawei.com Cc: morten.rasmussen@arm.com Cc: qperret@google.com Cc: tj@kernel.org Cc: vincent.guittot@linaro.org Fixes: 05484e098448 ("sched/topology: Add SD_ASYM_CPUCAPACITY flag detection") Link: https://lkml.kernel.org/r/20191023153745.19515-2-valentin.schneider@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-28perf/core: Start rejecting the syscall with attr.__reserved_2 setAlexander Shishkin
Commit: 1a5941312414c ("perf: Add wakeup watermark control to the AUX area") added attr.__reserved_2 padding, but forgot to add an ABI check to reject attributes with this field set. Fix that. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: adrian.hunter@intel.com Cc: mathieu.poirier@linaro.org Link: https://lkml.kernel.org/r/20191025121636.75182-1-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-27Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "A small set of fixes for time(keeping): - Add a missing include to prevent compiler warnings. - Make the VDSO implementation of clock_getres() POSIX compliant again. A recent change dropped the NULL pointer guard which is required as NULL is a valid pointer value for this function. - Fix two function documentation typos" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: posix-cpu-timers: Fix two trivial comments timers/sched_clock: Include local timekeeping.h for missing declarations lib/vdso: Make clock_getres() POSIX compliant again
2019-10-27Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "A set of perf fixes: kernel: - Unbreak the tracking of auxiliary buffer allocations which got imbalanced causing recource limit failures. - Fix the fallout of splitting of ToPA entries which missed to shift the base entry PA correctly. - Use the correct context to lookup the AUX event when unmapping the associated AUX buffer so the event can be stopped and the buffer reference dropped. tools: - Fix buildiid-cache mode setting in copyfile_mode_ns() when copying /proc/kcore - Fix freeing id arrays in the event list so the correct event is closed. - Sync sched.h anc kvm.h headers with the kernel sources. - Link jvmti against tools/lib/ctype.o to have weak strlcpy(). - Fix multiple memory and file descriptor leaks, found by coverity in perf annotate. - Fix leaks in error handling paths in 'perf c2c', 'perf kmem', found by a static analysis tool" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/aux: Fix AUX output stopping perf/aux: Fix tracking of auxiliary trace buffer allocation perf/x86/intel/pt: Fix base for single entry topa perf kmem: Fix memory leak in compact_gfp_flags() tools headers UAPI: Sync sched.h with the kernel tools headers kvm: Sync kvm.h headers with the kernel sources tools headers kvm: Sync kvm headers with the kernel sources tools headers kvm: Sync kvm headers with the kernel sources perf c2c: Fix memory leak in build_cl_output() perf tools: Fix mode setting in copyfile_mode_ns() perf annotate: Fix multiple memory and file descriptor leaks perf tools: Fix resource leak of closedir() on the error paths perf evlist: Fix fix for freed id arrays perf jvmti: Link against tools/lib/ctype.h to have weak strlcpy()
2019-10-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf 2019-10-27 The following pull-request contains BPF updates for your *net* tree. We've added 7 non-merge commits during the last 11 day(s) which contain a total of 7 files changed, 66 insertions(+), 16 deletions(-). The main changes are: 1) Fix two use-after-free bugs in relation to RCU in jited symbol exposure to kallsyms, from Daniel Borkmann. 2) Fix NULL pointer dereference in AF_XDP rx-only sockets, from Magnus Karlsson. 3) Fix hang in netdev unregister for hash based devmap as well as another overflow bug on 32 bit archs in memlock cost calculation, from Toke Høiland-Jørgensen. 4) Fix wrong memory access in LWT BPF programs on reroute due to invalid dst. Also fix BPF selftests to use more compatible nc options, from Jiri Benc. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-24Merge tag 'pm-5.4-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fixes from Rafael Wysocki: "These fix problems related to frequency limits management in cpufreq that were introduced during the 5.3 cycle (when PM QoS had started to be used for that), fix a few issues in the OPP (operating performance points) library code and fix up the recently added haltpoll cpuidle driver. The cpufreq changes are somewhat bigger that I would like them to be at this stage of the cycle, but the problems fixed by them include crashes on boot and shutdown in some cases (among other things) and in my view it is better to address the root of the issue right away. Specifics: - Using device PM QoS of CPU devices for managing frequency limits in cpufreq does not work, so introduce frequency QoS (based on the original low-level PM QoS) for this purpose, switch cpufreq and related code over to using it and fix a race involving deferred updates of frequency limits on top of that (Rafael Wysocki, Sudeep Holla). - Avoid calling regulator_enable()/disable() from the OPP framework to avoid side-effects on boot-enabled regulators that may change their initial voltage due to performing initial voltage balancing without all restrictions from the consumers (Marek Szyprowski). - Avoid a kref management issue in the OPP library code and drop an incorrectly added lockdep_assert_held() from it (Viresh Kumar). - Make the recently added haltpoll cpuidle driver take the 'idle=' override into account as appropriate (Zhenzhong Duan)" * tag 'pm-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: opp: Reinitialize the list_kref before adding the static OPPs again cpufreq: Cancel policy update work scheduled before freeing cpuidle: haltpoll: Take 'idle=' override into account opp: core: Revert "add regulators enable and disable" PM: QoS: Drop frequency QoS types from device PM QoS cpufreq: Use per-policy frequency QoS PM: QoS: Introduce frequency QoS opp: of: drop incorrect lockdep_assert_held()
2019-10-23Merge tag 'trace-v5.4-rc3-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Two minor fixes: - A race in perf trace initialization (missing mutexes) - Minor fix to represent gfp_t in synthetic events as properly signed" * tag 'trace-v5.4-rc3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Fix race in perf_trace_buf initialization tracing: Fix "gfp_t" format for synthetic events
2019-10-23posix-cpu-timers: Fix two trivial commentsYi Wang
Recent changes modified the function arguments of thread_group_sample_cputime() and task_cputimers_expired(), but forgot to update the comments. Fix it up. [ tglx: Changed the argument name of task_cputimers_expired() as the pointer points to an array of samples. ] Fixes: b7be4ef1365d ("posix-cpu-timers: Switch thread group sampling to array") Fixes: 001f7971433a ("posix-cpu-timers: Make expiry checks array based") Signed-off-by: Yi Wang <wang.yi59@zte.com.cn> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/1571643852-21848-1-git-send-email-wang.yi59@zte.com.cn
2019-10-23timers/sched_clock: Include local timekeeping.h for missing declarationsBen Dooks (Codethink)
Include the timekeeping.h header to get the declaration of the sched_clock_{suspend,resume} functions. Fixes the following sparse warnings: kernel/time/sched_clock.c:275:5: warning: symbol 'sched_clock_suspend' was not declared. Should it be static? kernel/time/sched_clock.c:286:6: warning: symbol 'sched_clock_resume' was not declared. Should it be static? Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20191022131226.11465-1-ben.dooks@codethink.co.uk
2019-10-22bpf: Fix use after free in bpf_get_prog_nameDaniel Borkmann
There is one more problematic case I noticed while recently fixing BPF kallsyms handling in cd7455f1013e ("bpf: Fix use after free in subprog's jited symbol removal") and that is bpf_get_prog_name(). If BTF has been attached to the prog, then we may be able to fetch the function signature type id in kallsyms through prog->aux->func_info[prog->aux->func_idx].type_id. However, while the BTF object itself is torn down via RCU callback, the prog's aux->func_info is immediately freed via kvfree(prog->aux->func_info) once the prog's refcount either hit zero or when subprograms were already exposed via kallsyms and we hit the error path added in 5482e9a93c83 ("bpf: Fix memleak in aux->func_info and aux->btf"). This violates RCU as well since kallsyms could be walked in parallel where we could access aux->func_info. Hence, defer kvfree() to after RCU grace period. Looking at ba64e7d85252 ("bpf: btf: support proper non-jit func info") there is no reason/dependency where we couldn't defer the kvfree(aux->func_info) into the RCU callback. Fixes: 5482e9a93c83 ("bpf: Fix memleak in aux->func_info and aux->btf") Fixes: ba64e7d85252 ("bpf: btf: support proper non-jit func info") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Cc: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/875f2906a7c1a0691f2d567b4d8e4ea2739b1e88.1571779205.git.daniel@iogearbox.net
2019-10-22bpf: Fix use after free in subprog's jited symbol removalDaniel Borkmann
syzkaller managed to trigger the following crash: [...] BUG: unable to handle page fault for address: ffffc90001923030 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD aa551067 P4D aa551067 PUD aa552067 PMD a572b067 PTE 80000000a1173163 Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 7982 Comm: syz-executor912 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:bpf_jit_binary_hdr include/linux/filter.h:787 [inline] RIP: 0010:bpf_get_prog_addr_region kernel/bpf/core.c:531 [inline] RIP: 0010:bpf_tree_comp kernel/bpf/core.c:600 [inline] RIP: 0010:__lt_find include/linux/rbtree_latch.h:115 [inline] RIP: 0010:latch_tree_find include/linux/rbtree_latch.h:208 [inline] RIP: 0010:bpf_prog_kallsyms_find kernel/bpf/core.c:674 [inline] RIP: 0010:is_bpf_text_address+0x184/0x3b0 kernel/bpf/core.c:709 [...] Call Trace: kernel_text_address kernel/extable.c:147 [inline] __kernel_text_address+0x9a/0x110 kernel/extable.c:102 unwind_get_return_address+0x4c/0x90 arch/x86/kernel/unwind_frame.c:19 arch_stack_walk+0x98/0xe0 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xb6/0x150 kernel/stacktrace.c:123 save_stack mm/kasan/common.c:69 [inline] set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc+0x11c/0x1b0 mm/kasan/common.c:510 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:518 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc mm/slab.c:3319 [inline] kmem_cache_alloc+0x1f5/0x2e0 mm/slab.c:3483 getname_flags+0xba/0x640 fs/namei.c:138 getname+0x19/0x20 fs/namei.c:209 do_sys_open+0x261/0x560 fs/open.c:1091 __do_sys_open fs/open.c:1115 [inline] __se_sys_open fs/open.c:1110 [inline] __x64_sys_open+0x87/0x90 fs/open.c:1110 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe [...] After further debugging it turns out that we walk kallsyms while in parallel we tear down a BPF program which contains subprograms that have been JITed though the program itself has not been fully exposed and is eventually bailing out with error. The bpf_prog_kallsyms_del_subprogs() in bpf_prog_load()'s error path removes the symbols, however, bpf_prog_free() tears down the JIT memory too early via scheduled work. Instead, it needs to properly respect RCU grace period as the kallsyms walk for BPF is under RCU. Fix it by refactoring __bpf_prog_put()'s tear down and reuse it in our error path where we defer final destruction when we have subprogs in the program. Fixes: 7d1982b4e335 ("bpf: fix panic in prog load calls cleanup") Fixes: 1c2a088a6626 ("bpf: x64: add JIT support for multi-function programs") Reported-by: syzbot+710043c5d1d5b5013bc7@syzkaller.appspotmail.com Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Tested-by: syzbot+710043c5d1d5b5013bc7@syzkaller.appspotmail.com Link: https://lore.kernel.org/bpf/55f6367324c2d7e9583fa9ccf5385dcbba0d7a6e.1571752452.git.daniel@iogearbox.net
2019-10-22perf/aux: Fix AUX output stoppingAlexander Shishkin
Commit: 8a58ddae2379 ("perf/core: Fix exclusive events' grouping") allows CAP_EXCLUSIVE events to be grouped with other events. Since all of those also happen to be AUX events (which is not the case the other way around, because arch/s390), this changes the rules for stopping the output: the AUX event may not be on its PMU's context any more, if it's grouped with a HW event, in which case it will be on that HW event's context instead. If that's the case, munmap() of the AUX buffer can't find and stop the AUX event, potentially leaving the last reference with the atomic context, which will then end up freeing the AUX buffer. This will then trip warnings: Fix this by using the context's PMU context when looking for events to stop, instead of the event's PMU context. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20191022073940.61814-1-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-21tracing: Fix race in perf_trace_buf initializationPrateek Sood
A race condition exists while initialiazing perf_trace_buf from perf_trace_init() and perf_kprobe_init(). CPU0 CPU1 perf_trace_init() mutex_lock(&event_mutex) perf_trace_event_init() perf_trace_event_reg() total_ref_count == 0 buf = alloc_percpu() perf_trace_buf[i] = buf tp_event->class->reg() //fails perf_kprobe_init() goto fail perf_trace_event_init() perf_trace_event_reg() fail: total_ref_count == 0 total_ref_count == 0 buf = alloc_percpu() perf_trace_buf[i] = buf tp_event->class->reg() total_ref_count++ free_percpu(perf_trace_buf[i]) perf_trace_buf[i] = NULL Any subsequent call to perf_trace_event_reg() will observe total_ref_count > 0, causing the perf_trace_buf to be always NULL. This can result in perf_trace_buf getting accessed from perf_trace_buf_alloc() without being initialized. Acquiring event_mutex in perf_kprobe_init() before calling perf_trace_event_init() should fix this race. The race caused the following bug: Unable to handle kernel paging request at virtual address 0000003106f2003c Mem abort info: ESR = 0x96000045 Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000045 CM = 0, WnR = 1 user pgtable: 4k pages, 39-bit VAs, pgdp = ffffffc034b9b000 [0000003106f2003c] pgd=0000000000000000, pud=0000000000000000 Internal error: Oops: 96000045 [#1] PREEMPT SMP Process syz-executor (pid: 18393, stack limit = 0xffffffc093190000) pstate: 80400005 (Nzcv daif +PAN -UAO) pc : __memset+0x20/0x1ac lr : memset+0x3c/0x50 sp : ffffffc09319fc50 __memset+0x20/0x1ac perf_trace_buf_alloc+0x140/0x1a0 perf_trace_sys_enter+0x158/0x310 syscall_trace_enter+0x348/0x7c0 el0_svc_common+0x11c/0x368 el0_svc_handler+0x12c/0x198 el0_svc+0x8/0xc Ramdumps showed the following: total_ref_count = 3 perf_trace_buf = ( 0x0 -> NULL, 0x0 -> NULL, 0x0 -> NULL, 0x0 -> NULL) Link: http://lkml.kernel.org/r/1571120245-4186-1-git-send-email-prsood@codeaurora.org Cc: stable@vger.kernel.org Fixes: e12f03d7031a9 ("perf/core: Implement the 'perf_kprobe' PMU") Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Prateek Sood <prsood@codeaurora.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-21xdp: Handle device unregister for devmap_hash map typeToke Høiland-Jørgensen
It seems I forgot to add handling of devmap_hash type maps to the device unregister hook for devmaps. This omission causes devices to not be properly released, which causes hangs. Fix this by adding the missing handler. Fixes: 6f9d451ab1a3 ("xdp: Add devmap_hash map type for looking up devices by hashed index") Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20191019111931.2981954-1-toke@redhat.com
2019-10-21perf/aux: Fix tracking of auxiliary trace buffer allocationThomas Richter
The following commit from the v5.4 merge window: d44248a41337 ("perf/core: Rework memory accounting in perf_mmap()") ... breaks auxiliary trace buffer tracking. If I run command 'perf record -e rbd000' to record samples and saving them in the **auxiliary** trace buffer then the value of 'locked_vm' becomes negative after all trace buffers have been allocated and released: During allocation the values increase: [52.250027] perf_mmap user->locked_vm:0x87 pinned_vm:0x0 ret:0 [52.250115] perf_mmap user->locked_vm:0x107 pinned_vm:0x0 ret:0 [52.250251] perf_mmap user->locked_vm:0x188 pinned_vm:0x0 ret:0 [52.250326] perf_mmap user->locked_vm:0x208 pinned_vm:0x0 ret:0 [52.250441] perf_mmap user->locked_vm:0x289 pinned_vm:0x0 ret:0 [52.250498] perf_mmap user->locked_vm:0x309 pinned_vm:0x0 ret:0 [52.250613] perf_mmap user->locked_vm:0x38a pinned_vm:0x0 ret:0 [52.250715] perf_mmap user->locked_vm:0x408 pinned_vm:0x2 ret:0 [52.250834] perf_mmap user->locked_vm:0x408 pinned_vm:0x83 ret:0 [52.250915] perf_mmap user->locked_vm:0x408 pinned_vm:0x103 ret:0 [52.251061] perf_mmap user->locked_vm:0x408 pinned_vm:0x184 ret:0 [52.251146] perf_mmap user->locked_vm:0x408 pinned_vm:0x204 ret:0 [52.251299] perf_mmap user->locked_vm:0x408 pinned_vm:0x285 ret:0 [52.251383] perf_mmap user->locked_vm:0x408 pinned_vm:0x305 ret:0 [52.251544] perf_mmap user->locked_vm:0x408 pinned_vm:0x386 ret:0 [52.251634] perf_mmap user->locked_vm:0x408 pinned_vm:0x406 ret:0 [52.253018] perf_mmap user->locked_vm:0x408 pinned_vm:0x487 ret:0 [52.253197] perf_mmap user->locked_vm:0x408 pinned_vm:0x508 ret:0 [52.253374] perf_mmap user->locked_vm:0x408 pinned_vm:0x589 ret:0 [52.253550] perf_mmap user->locked_vm:0x408 pinned_vm:0x60a ret:0 [52.253726] perf_mmap user->locked_vm:0x408 pinned_vm:0x68b ret:0 [52.253903] perf_mmap user->locked_vm:0x408 pinned_vm:0x70c ret:0 [52.254084] perf_mmap user->locked_vm:0x408 pinned_vm:0x78d ret:0 [52.254263] perf_mmap user->locked_vm:0x408 pinned_vm:0x80e ret:0 The value of user->locked_vm increases to a limit then the memory is tracked by pinned_vm. During deallocation the size is subtracted from pinned_vm until it hits a limit. Then a larger value is subtracted from locked_vm leading to a large number (because of type unsigned): [64.267797] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x78d [64.267826] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x70c [64.267848] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x68b [64.267869] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x60a [64.267891] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x589 [64.267911] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x508 [64.267933] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x487 [64.267952] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x406 [64.268883] perf_mmap_close mmap_user->locked_vm:0x307 pinned_vm:0x406 [64.269117] perf_mmap_close mmap_user->locked_vm:0x206 pinned_vm:0x406 [64.269433] perf_mmap_close mmap_user->locked_vm:0x105 pinned_vm:0x406 [64.269536] perf_mmap_close mmap_user->locked_vm:0x4 pinned_vm:0x404 [64.269797] perf_mmap_close mmap_user->locked_vm:0xffffffffffffff84 pinned_vm:0x303 [64.270105] perf_mmap_close mmap_user->locked_vm:0xffffffffffffff04 pinned_vm:0x202 [64.270374] perf_mmap_close mmap_user->locked_vm:0xfffffffffffffe84 pinned_vm:0x101 [64.270628] perf_mmap_close mmap_user->locked_vm:0xfffffffffffffe04 pinned_vm:0x0 This value sticks for the user until system is rebooted, causing follow-on system calls using locked_vm resource limit to fail. Note: There is no issue using the normal trace buffer. In fact the issue is in perf_mmap_close(). During allocation auxiliary trace buffer memory is either traced as 'extra' and added to 'pinned_vm' or trace as 'user_extra' and added to 'locked_vm'. This applies for normal trace buffers and auxiliary trace buffer. However in function perf_mmap_close() all auxiliary trace buffer is subtraced from 'locked_vm' and never from 'pinned_vm'. This breaks the ballance. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@kernel.org Cc: gor@linux.ibm.com Cc: hechaol@fb.com Cc: heiko.carstens@de.ibm.com Cc: linux-perf-users@vger.kernel.org Cc: songliubraving@fb.com Fixes: d44248a41337 ("perf/core: Rework memory accounting in perf_mmap()") Link: https://lkml.kernel.org/r/20191021083354.67868-1-tmricht@linux.ibm.com [ Minor readability edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-21PM: QoS: Introduce frequency QoSRafael J. Wysocki
Introduce frequency QoS, based on the "raw" low-level PM QoS, to represent min and max frequency requests and aggregate constraints. The min and max frequency requests are to be represented by struct freq_qos_request objects and the aggregate constraints are to be represented by struct freq_constraints objects. The latter are expected to be initialized with the help of freq_constraints_init(). The freq_qos_read_value() helper is defined to retrieve the aggregate constraints values from a given struct freq_constraints object and there are the freq_qos_add_request(), freq_qos_update_request() and freq_qos_remove_request() helpers to manipulate the min and max frequency requests. It is assumed that the the helpers will not run concurrently with each other for the same struct freq_qos_request object, so if that may be the case, their uses must ensure proper synchronization between them (e.g. through locking). In addition, freq_qos_add_notifier() and freq_qos_remove_notifier() are provided to add and remove notifiers that will trigger on aggregate constraint changes to and from a given struct freq_constraints object, respectively. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2019-10-20Merge tag 'kbuild-fixes-v5.4-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild fixes from Masahiro Yamada: - fix a bashism of setlocalversion - do not use the too new --sort option of tar * tag 'kbuild-fixes-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kheaders: substituting --sort in archive creation scripts: setlocalversion: fix a bashism kbuild: update comment about KBUILD_ALLDIRS
2019-10-20Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull hrtimer fixlet from Thomas Gleixner: "A single commit annotating the lockcless access to timer->base with READ_ONCE() and adding the WRITE_ONCE() counterparts for completeness" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: hrtimer: Annotate lockless access to timer->base
2019-10-20Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull stop-machine fix from Thomas Gleixner: "A single fix, amending stop machine with WRITE/READ_ONCE() to address the fallout of KCSAN" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: stop_machine: Avoid potential race behaviour
2019-10-19kernel/events/uprobes.c: only do FOLL_SPLIT_PMD for uprobe registerSong Liu
Attaching uprobe to text section in THP splits the PMD mapped page table into PTE mapped entries. On uprobe detach, we would like to regroup PMD mapped page table entry to regain performance benefit of THP. However, the regroup is broken For perf_event based trace_uprobe. This is because perf_event based trace_uprobe calls uprobe_unregister twice on close: first in TRACE_REG_PERF_CLOSE, then in TRACE_REG_PERF_UNREGISTER. The second call will split the PMD mapped page table entry, which is not the desired behavior. Fix this by only use FOLL_SPLIT_PMD for uprobe register case. Add a WARN() to confirm uprobe unregister never work on huge pages, and abort the operation when this WARN() triggers. Link: http://lkml.kernel.org/r/20191017164223.2762148-6-songliubraving@fb.com Fixes: 5a52c9df62b4 ("uprobe: use FOLL_SPLIT_PMD instead of FOLL_SPLIT") Signed-off-by: Song Liu <songliubraving@fb.com> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: William Kucharski <william.kucharski@oracle.com> Cc: Yang Shi <yang.shi@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-18xdp: Prevent overflow in devmap_hash cost calculation for 32-bit buildsToke Høiland-Jørgensen
Tetsuo pointed out that without an explicit cast, the cost calculation for devmap_hash type maps could overflow on 32-bit builds. This adds the missing cast. Fixes: 6f9d451ab1a3 ("xdp: Add devmap_hash map type for looking up devices by hashed index") Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20191017105702.2807093-1-toke@redhat.com
2019-10-18tracing: Fix "gfp_t" format for synthetic eventsZhengjun Xing
In the format of synthetic events, the "gfp_t" is shown as "signed:1", but in fact the "gfp_t" is "unsigned", should be shown as "signed:0". The issue can be reproduced by the following commands: echo 'memlatency u64 lat; unsigned int order; gfp_t gfp_flags; int migratetype' > /sys/kernel/debug/tracing/synthetic_events cat /sys/kernel/debug/tracing/events/synthetic/memlatency/format name: memlatency ID: 2233 format: field:unsigned short common_type; offset:0; size:2; signed:0; field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1; signed:0; field:int common_pid; offset:4; size:4; signed:1; field:u64 lat; offset:8; size:8; signed:0; field:unsigned int order; offset:16; size:4; signed:0; field:gfp_t gfp_flags; offset:24; size:4; signed:1; field:int migratetype; offset:32; size:4; signed:1; print fmt: "lat=%llu, order=%u, gfp_flags=%x, migratetype=%d", REC->lat, REC->order, REC->gfp_flags, REC->migratetype Link: http://lkml.kernel.org/r/20191018012034.6404-1-zhengjun.xing@linux.intel.com Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-18Merge tag 'pm-5.4-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fixes from Rafael Wysocki: "These include a fix for a recent regression in the ACPI CPU performance scaling code, a PCI device power management fix, a system shutdown fix related to cpufreq, a removal of an ACPI suspend-to-idle blacklist entry and a build warning fix. Specifics: - Fix possible NULL pointer dereference in the ACPI processor scaling initialization code introduced by a recent cpufreq update (Rafael Wysocki). - Fix possible deadlock due to suspending cpufreq too late during system shutdown (Rafael Wysocki). - Make the PCI device system resume code path be more consistent with its PM-runtime counterpart to fix an issue with missing delay on transitions from D3cold to D0 during system resume from suspend-to-idle on some systems (Rafael Wysocki). - Drop Dell XPS13 9360 from the LPS0 Idle _DSM blacklist to make it use suspend-to-idle by default (Mario Limonciello). - Fix build warning in the core system suspend support code (Ben Dooks)" * tag 'pm-5.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI: processor: Avoid NULL pointer dereferences at init time PCI: PM: Fix pci_power_up() PM: sleep: include <linux/pm_runtime.h> for pm_wq cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist
2019-10-18Merge branches 'pm-cpufreq' and 'pm-sleep'Rafael J. Wysocki
* pm-cpufreq: ACPI: processor: Avoid NULL pointer dereferences at init time cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown * pm-sleep: PM: sleep: include <linux/pm_runtime.h> for pm_wq ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist
2019-10-17stop_machine: Avoid potential race behaviourMark Rutland
Both multi_cpu_stop() and set_state() access multi_stop_data::state racily using plain accesses. These are subject to compiler transformations which could break the intended behaviour of the code, and this situation is detected by KCSAN on both arm64 and x86 (splats below). Improve matters by using READ_ONCE() and WRITE_ONCE() to ensure that the compiler cannot elide, replay, or tear loads and stores. In multi_cpu_stop() the two loads of multi_stop_data::state are expected to be a consistent value, so snapshot the value into a temporary variable to ensure this. The state transitions are serialized by atomic manipulation of multi_stop_data::num_threads, and other fields in multi_stop_data are not modified while subject to concurrent reads. KCSAN splat on arm64: | BUG: KCSAN: data-race in multi_cpu_stop+0xa8/0x198 and set_state+0x80/0xb0 | | write to 0xffff00001003bd00 of 4 bytes by task 24 on cpu 3: | set_state+0x80/0xb0 | multi_cpu_stop+0x16c/0x198 | cpu_stopper_thread+0x170/0x298 | smpboot_thread_fn+0x40c/0x560 | kthread+0x1a8/0x1b0 | ret_from_fork+0x10/0x18 | | read to 0xffff00001003bd00 of 4 bytes by task 14 on cpu 1: | multi_cpu_stop+0xa8/0x198 | cpu_stopper_thread+0x170/0x298 | smpboot_thread_fn+0x40c/0x560 | kthread+0x1a8/0x1b0 | ret_from_fork+0x10/0x18 | | Reported by Kernel Concurrency Sanitizer on: | CPU: 1 PID: 14 Comm: migration/1 Not tainted 5.3.0-00007-g67ab35a199f4-dirty #3 | Hardware name: linux,dummy-virt (DT) KCSAN splat on x86: | write to 0xffffb0bac0013e18 of 4 bytes by task 19 on cpu 2: | set_state kernel/stop_machine.c:170 [inline] | ack_state kernel/stop_machine.c:177 [inline] | multi_cpu_stop+0x1a4/0x220 kernel/stop_machine.c:227 | cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516 | smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165 | kthread+0x1b5/0x200 kernel/kthread.c:255 | ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352 | | read to 0xffffb0bac0013e18 of 4 bytes by task 44 on cpu 7: | multi_cpu_stop+0xb4/0x220 kernel/stop_machine.c:213 | cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516 | smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165 | kthread+0x1b5/0x200 kernel/kthread.c:255 | ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352 | | Reported by Kernel Concurrency Sanitizer on: | CPU: 7 PID: 44 Comm: migration/7 Not tainted 5.3.0+ #1 | Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marco Elver <elver@google.com> Link: https://lkml.kernel.org/r/20191007104536.27276-1-mark.rutland@arm.com
2019-10-17kheaders: substituting --sort in archive creationDmitry Goldin
The option --sort=ORDER was only introduced in tar 1.28 (2014), which is rather new and might not be available in some setups. This patch tries to replicate the previous behaviour as closely as possible to fix the kheaders build for older environments. It does not produce identical archives compared to the previous version due to minor sorting differences but produces reproducible results itself in my tests. Reported-by: Andreas Schwab <schwab@suse.de> Signed-off-by: Dmitry Goldin <dgoldin+lkml@protonmail.ch> Tested-by: Andreas Schwab <schwab@suse.de> Tested-by: Quentin Perret <qperret@google.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-10-16kthread: make __kthread_queue_delayed_work staticBen Dooks
The __kthread_queue_delayed_work is not exported so make it static, to avoid the following sparse warning: kernel/kthread.c:869:6: warning: symbol '__kthread_queue_delayed_work' was not declared. Should it be static? Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-15Merge branch 'parisc-5.4-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux Pull parisc fixes from Helge Deller: - Fix a parisc-specific fallout of Christoph's dma_set_mask_and_coherent() patches (Sven) - Fix a vmap memory leak in ioremap()/ioremap() (Helge) - Some minor cleanups and documentation updates (Nick, Helge) * 'parisc-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: parisc: Remove 32-bit DMA enforcement from sba_iommu parisc: Fix vmap memory leak in ioremap()/iounmap() parisc: prefer __section from compiler_attributes.h parisc: sysctl.c: Use CONFIG_PARISC instead of __hppa_ define MAINTAINERS: Add hp_sdc drivers to parisc arch
2019-10-14parisc: sysctl.c: Use CONFIG_PARISC instead of __hppa_ defineHelge Deller
Signed-off-by: Helge Deller <deller@gmx.de>
2019-10-14hrtimer: Annotate lockless access to timer->baseEric Dumazet
Followup to commit dd2261ed45aa ("hrtimer: Protect lockless access to timer->base") lock_hrtimer_base() fetches timer->base without lock exclusion. Compiler is allowed to read timer->base twice (even if considered dumb) which could end up trying to lock migration_base and return &migration_base. base = timer->base; if (likely(base != &migration_base)) { /* compiler reads timer->base again, and now (base == &migration_base) raw_spin_lock_irqsave(&base->cpu_base->lock, *flags); if (likely(base == timer->base)) return base; /* == &migration_base ! */ Similarly the write sides must use WRITE_ONCE() to avoid store tearing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20191008173204.180879-1-edumazet@google.com
2019-10-13Merge tag 'trace-v5.4-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "A few tracing fixes: - Remove lockdown from tracefs itself and moved it to the trace directory. Have the open functions there do the lockdown checks. - Fix a few races with opening an instance file and the instance being deleted (Discovered during the lockdown updates). Kept separate from the clean up code such that they can be backported to stable easier. - Clean up and consolidated the checks done when opening a trace file, as there were multiple checks that need to be done, and it did not make sense having them done in each open instance. - Fix a regression in the record mcount code. - Small hw_lat detector tracer fixes. - A trace_pipe read fix due to not initializing trace_seq" * tag 'trace-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Initialize iter->seq after zeroing in tracing_read_pipe() tracing/hwlat: Don't ignore outer-loop duration when calculating max_latency tracing/hwlat: Report total time spent in all NMIs during the sample recordmcount: Fix nop_mcount() function tracing: Do not create tracefs files if tracefs lockdown is in effect tracing: Add locked_down checks to the open calls of files created for tracefs tracing: Add tracing_check_open_get_tr() tracing: Have trace events system open call tracing_open_generic_tr() tracing: Get trace_array reference for available_tracers files ftrace: Get a reference counter for the trace_array on filter files tracefs: Revert ccbd54ff54e8 ("tracefs: Restrict tracefs when the kernel is locked down")
2019-10-12tracing: Initialize iter->seq after zeroing in tracing_read_pipe()Petr Mladek
A customer reported the following softlockup: [899688.160002] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [test.sh:16464] [899688.160002] CPU: 0 PID: 16464 Comm: test.sh Not tainted 4.12.14-6.23-azure #1 SLE12-SP4 [899688.160002] RIP: 0010:up_write+0x1a/0x30 [899688.160002] Kernel panic - not syncing: softlockup: hung tasks [899688.160002] RIP: 0010:up_write+0x1a/0x30 [899688.160002] RSP: 0018:ffffa86784d4fde8 EFLAGS: 00000257 ORIG_RAX: ffffffffffffff12 [899688.160002] RAX: ffffffff970fea00 RBX: 0000000000000001 RCX: 0000000000000000 [899688.160002] RDX: ffffffff00000001 RSI: 0000000000000080 RDI: ffffffff970fea00 [899688.160002] RBP: ffffffffffffffff R08: ffffffffffffffff R09: 0000000000000000 [899688.160002] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8b59014720d8 [899688.160002] R13: ffff8b59014720c0 R14: ffff8b5901471090 R15: ffff8b5901470000 [899688.160002] tracing_read_pipe+0x336/0x3c0 [899688.160002] __vfs_read+0x26/0x140 [899688.160002] vfs_read+0x87/0x130 [899688.160002] SyS_read+0x42/0x90 [899688.160002] do_syscall_64+0x74/0x160 It caught the process in the middle of trace_access_unlock(). There is no loop. So, it must be looping in the caller tracing_read_pipe() via the "waitagain" label. Crashdump analyze uncovered that iter->seq was completely zeroed at this point, including iter->seq.seq.size. It means that print_trace_line() was never able to print anything and there was no forward progress. The culprit seems to be in the code: /* reset all but tr, trace, and overruns */ memset(&iter->seq, 0, sizeof(struct trace_iterator) - offsetof(struct trace_iterator, seq)); It was added by the commit 53d0aa773053ab182877 ("ftrace: add logic to record overruns"). It was v2.6.27-rc1. It was the time when iter->seq looked like: struct trace_seq { unsigned char buffer[PAGE_SIZE]; unsigned int len; }; There was no "size" variable and zeroing was perfectly fine. The solution is to reinitialize the structure after or without zeroing. Link: http://lkml.kernel.org/r/20191011142134.11997-1-pmladek@suse.com Signed-off-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12tracing/hwlat: Don't ignore outer-loop duration when calculating max_latencySrivatsa S. Bhat (VMware)
max_latency is intended to record the maximum ever observed hardware latency, which may occur in either part of the loop (inner/outer). So we need to also consider the outer-loop sample when updating max_latency. Link: http://lkml.kernel.org/r/157073345463.17189.18124025522664682811.stgit@srivatsa-ubuntu Fixes: e7c15cd8a113 ("tracing: Added hardware latency tracer") Cc: stable@vger.kernel.org Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12tracing/hwlat: Report total time spent in all NMIs during the sampleSrivatsa S. Bhat (VMware)
nmi_total_ts is supposed to record the total time spent in *all* NMIs that occur on the given CPU during the (active portion of the) sampling window. However, the code seems to be overwriting this variable for each NMI, thereby only recording the time spent in the most recent NMI. Fix it by accumulating the duration instead. Link: http://lkml.kernel.org/r/157073343544.17189.13911783866738671133.stgit@srivatsa-ubuntu Fixes: 7b2c86250122 ("tracing: Add NMI tracing in hwlat detector") Cc: stable@vger.kernel.org Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12tracing: Add locked_down checks to the open calls of files created for tracefsSteven Rostedt (VMware)
Added various checks on open tracefs calls to see if tracefs is in lockdown mode, and if so, to return -EPERM. Note, the event format files (which are basically standard on all machines) as well as the enabled_functions file (which shows what is currently being traced) are not lockde down. Perhaps they should be, but it seems counter intuitive to lockdown information to help you know if the system has been modified. Link: http://lkml.kernel.org/r/CAHk-=wj7fGPKUspr579Cii-w_y60PtRaiDgKuxVtBAMK0VNNkA@mail.gmail.com Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12tracing: Add tracing_check_open_get_tr()Steven Rostedt (VMware)
Currently, most files in the tracefs directory test if tracing_disabled is set. If so, it should return -ENODEV. The tracing_disabled is called when tracing is found to be broken. Originally it was done in case the ring buffer was found to be corrupted, and we wanted to prevent reading it from crashing the kernel. But it's also called if a tracing selftest fails on boot. It's a one way switch. That is, once it is triggered, tracing is disabled until reboot. As most tracefs files can also be used by instances in the tracefs directory, they need to be carefully done. Each instance has a trace_array associated to it, and when the instance is removed, the trace_array is freed. But if an instance is opened with a reference to the trace_array, then it requires looking up the trace_array to get its ref counter (as there could be a race with it being deleted and the open itself). Once it is found, a reference is added to prevent the instance from being removed (and the trace_array associated with it freed). Combine the two checks (tracing_disabled and trace_array_get()) into a single helper function. This will also make it easier to add lockdown to tracefs later. Link: http://lkml.kernel.org/r/20191011135458.7399da44@gandalf.local.home Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12tracing: Have trace events system open call tracing_open_generic_tr()Steven Rostedt (VMware)
Instead of having the trace events system open call open code the taking of the trace_array descriptor (with trace_array_get()) and then calling trace_open_generic(), have it use the tracing_open_generic_tr() that does the combination of the two. This requires making tracing_open_generic_tr() global. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12tracing: Get trace_array reference for available_tracers filesSteven Rostedt (VMware)
As instances may have different tracers available, we need to look at the trace_array descriptor that shows the list of the available tracers for the instance. But there's a race between opening the file and an admin deleting the instance. The trace_array_get() needs to be called before accessing the trace_array. Cc: stable@vger.kernel.org Fixes: 607e2ea167e56 ("tracing: Set up infrastructure to allow tracers for instances") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12ftrace: Get a reference counter for the trace_array on filter filesSteven Rostedt (VMware)
The ftrace set_ftrace_filter and set_ftrace_notrace files are specific for an instance now. They need to take a reference to the instance otherwise there could be a race between accessing the files and deleting the instance. It wasn't until the :mod: caching where these file operations started referencing the trace_array directly. Cc: stable@vger.kernel.org Fixes: 673feb9d76ab3 ("ftrace: Add :mod: caching infrastructure to trace_array") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "Two fixes: a guest-cputime accounting fix, and a cgroup bandwidth quota precision fix" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/vtime: Fix guest/system mis-accounting on task switch sched/fair: Scale bandwidth quota and period without losing quota/period ratio precision
2019-10-12Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Mostly tooling fixes, but also a couple of updates for new Intel models (which are technically hw-enablement, but to users it's a fix to perf behavior on those new CPUs - hope this is fine), an AUX inheritance fix, event time-sharing fix, and a fix for lost non-perf NMI events on AMD systems" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) perf/x86/cstate: Add Tiger Lake CPU support perf/x86/msr: Add Tiger Lake CPU support perf/x86/intel: Add Tiger Lake CPU support perf/x86/cstate: Update C-state counters for Ice Lake perf/x86/msr: Add new CPU model numbers for Ice Lake perf/x86/cstate: Add Comet Lake CPU support perf/x86/msr: Add Comet Lake CPU support perf/x86/intel: Add Comet Lake CPU support perf/x86/amd: Change/fix NMI latency mitigation to use a timestamp perf/core: Fix corner case in perf_rotate_context() perf/core: Rework memory accounting in perf_mmap() perf/core: Fix inheritance of aux_output groups perf annotate: Don't return -1 for error when doing BPF disassembly perf annotate: Return appropriate error code for allocation failures perf annotate: Fix arch specific ->init() failure errors perf annotate: Propagate the symbol__annotate() error return perf annotate: Fix the signedness of failure returns perf annotate: Propagate perf_env__arch() error perf evsel: Fall back to global 'perf_env' in perf_evsel__env() perf tools: Propagate get_cpuid() error ...
2019-10-11Merge tag 'for-linus-20191010' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: - Fix wbt performance regression introduced with the blk-rq-qos refactoring (Harshad) - Fix io_uring fileset removal inadvertently killing the workqueue (me) - Fix io_uring typo in linked command nonblock submission (Pavel) - Remove spurious io_uring wakeups on request free (Pavel) - Fix null_blk zoned command error return (Keith) - Don't use freezable workqueues for backing_dev, also means we can revert a previous libata hack (Mika) - Fix nbd sysfs mutex dropped too soon at removal time (Xiubo) * tag 'for-linus-20191010' of git://git.kernel.dk/linux-block: nbd: fix possible sysfs duplicate warning null_blk: Fix zoned command return code io_uring: only flush workqueues on fileset removal io_uring: remove wait loop spurious wakeups blk-wbt: fix performance regression in wbt scale_up/scale_down Revert "libata, freezer: avoid block device removal while system is frozen" bdi: Do not use freezable workqueue io_uring: fix reversed nonblock flag for link submission