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2020-03-29Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge vm fixes from Andrew Morton: "5 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mm/sparse: fix kernel crash with pfn_section_valid check mm: fork: fix kernel_stack memcg stats for various stack implementations hugetlb_cgroup: fix illegal access to memory drivers/base/memory.c: indicate all memory blocks as removable mm/swapfile.c: move inode_lock out of claim_swapfile
2020-03-29Merge tag 'irq-urgent-2020-03-29' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fix from Thomas Gleixner: "A single bugfix to prevent reference leaks in irq affinity notifiers" * tag 'irq-urgent-2020-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Fix reference leaks on irq affinity notifiers
2020-03-29mm: fork: fix kernel_stack memcg stats for various stack implementationsRoman Gushchin
Depending on CONFIG_VMAP_STACK and the THREAD_SIZE / PAGE_SIZE ratio the space for task stacks can be allocated using __vmalloc_node_range(), alloc_pages_node() and kmem_cache_alloc_node(). In the first and the second cases page->mem_cgroup pointer is set, but in the third it's not: memcg membership of a slab page should be determined using the memcg_from_slab_page() function, which looks at page->slab_cache->memcg_params.memcg . In this case, using mod_memcg_page_state() (as in account_kernel_stack()) is incorrect: page->mem_cgroup pointer is NULL even for pages charged to a non-root memory cgroup. It can lead to kernel_stack per-memcg counters permanently showing 0 on some architectures (depending on the configuration). In order to fix it, let's introduce a mod_memcg_obj_state() helper, which takes a pointer to a kernel object as a first argument, uses mem_cgroup_from_obj() to get a RCU-protected memcg pointer and calls mod_memcg_state(). It allows to handle all possible configurations (CONFIG_VMAP_STACK and various THREAD_SIZE/PAGE_SIZE values) without spilling any memcg/kmem specifics into fork.c . Note: This is a special version of the patch created for stable backports. It contains code from the following two patches: - mm: memcg/slab: introduce mem_cgroup_from_obj() - mm: fork: fix kernel_stack memcg stats for various stack implementations [guro@fb.com: introduce mem_cgroup_from_obj()] Link: http://lkml.kernel.org/r/20200324004221.GA36662@carbon.dhcp.thefacebook.com Fixes: 4d96ba353075 ("mm: memcg/slab: stop setting page->mem_cgroup pointer for slab pages") Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Bharata B Rao <bharata@linux.ibm.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200303233550.251375-1-guro@fb.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-28Merge branch 'uaccess.futex' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs into locking/core Pull uaccess futex cleanups for Al Viro: Consolidate access_ok() usage and the futex uaccess function zoo.
2020-03-28cpu/hotplug: Ignore pm_wakeup_pending() for disable_nonboot_cpus()Thomas Gleixner
A recent change to freeze_secondary_cpus() which added an early abort if a wakeup is pending missed the fact that the function is also invoked for shutdown, reboot and kexec via disable_nonboot_cpus(). In case of disable_nonboot_cpus() the wakeup event needs to be ignored as the purpose is to terminate the currently running kernel. Add a 'suspend' argument which is only set when the freeze is in context of a suspend operation. If not set then an eventually pending wakeup event is ignored. Fixes: a66d955e910a ("cpu/hotplug: Abort disabling secondary CPUs if wakeup is pending") Reported-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Pavankumar Kondeti <pkondeti@codeaurora.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/874kuaxdiz.fsf@nanos.tec.linutronix.de
2020-03-27futex: arch_futex_atomic_op_inuser() calling conventions changeAl Viro
Move access_ok() in and pagefault_enable()/pagefault_disable() out. Mechanical conversion only - some instances don't really need a separate access_ok() at all (e.g. the ones only using get_user()/put_user(), or architectures where access_ok() is always true); we'll deal with that in followups. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-27bpf: Enable bpf cgroup hooks to retrieve cgroup v2 and ancestor idDaniel Borkmann
Enable the bpf_get_current_cgroup_id() helper for connect(), sendmsg(), recvmsg() and bind-related hooks in order to retrieve the cgroup v2 context which can then be used as part of the key for BPF map lookups, for example. Given these hooks operate in process context 'current' is always valid and pointing to the app that is performing mentioned syscalls if it's subject to a v2 cgroup. Also with same motivation of commit 7723628101aa ("bpf: Introduce bpf_skb_ancestor_cgroup_id helper") enable retrieval of ancestor from current so the cgroup id can be used for policy lookups which can then forbid connect() / bind(), for example. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/d2a7ef42530ad299e3cbb245e6c12374b72145ef.1585323121.git.daniel@iogearbox.net
2020-03-27bpf: Add netns cookie and enable it for bpf cgroup hooksDaniel Borkmann
In Cilium we're mainly using BPF cgroup hooks today in order to implement kube-proxy free Kubernetes service translation for ClusterIP, NodePort (*), ExternalIP, and LoadBalancer as well as HostPort mapping [0] for all traffic between Cilium managed nodes. While this works in its current shape and avoids packet-level NAT for inter Cilium managed node traffic, there is one major limitation we're facing today, that is, lack of netns awareness. In Kubernetes, the concept of Pods (which hold one or multiple containers) has been built around network namespaces, so while we can use the global scope of attaching to root BPF cgroup hooks also to our advantage (e.g. for exposing NodePort ports on loopback addresses), we also have the need to differentiate between initial network namespaces and non-initial one. For example, ExternalIP services mandate that non-local service IPs are not to be translated from the host (initial) network namespace as one example. Right now, we have an ugly work-around in place where non-local service IPs for ExternalIP services are not xlated from connect() and friends BPF hooks but instead via less efficient packet-level NAT on the veth tc ingress hook for Pod traffic. On top of determining whether we're in initial or non-initial network namespace we also have a need for a socket-cookie like mechanism for network namespaces scope. Socket cookies have the nice property that they can be combined as part of the key structure e.g. for BPF LRU maps without having to worry that the cookie could be recycled. We are planning to use this for our sessionAffinity implementation for services. Therefore, add a new bpf_get_netns_cookie() helper which would resolve both use cases at once: bpf_get_netns_cookie(NULL) would provide the cookie for the initial network namespace while passing the context instead of NULL would provide the cookie from the application's network namespace. We're using a hole, so no size increase; the assignment happens only once. Therefore this allows for a comparison on initial namespace as well as regular cookie usage as we have today with socket cookies. We could later on enable this helper for other program types as well as we would see need. (*) Both externalTrafficPolicy={Local|Cluster} types [0] https://github.com/cilium/cilium/blob/master/bpf/bpf_sock.c Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/c47d2346982693a9cf9da0e12690453aded4c788.1585323121.git.daniel@iogearbox.net
2020-03-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf 2020-03-27 The following pull-request contains BPF updates for your *net* tree. We've added 3 non-merge commits during the last 4 day(s) which contain a total of 4 files changed, 25 insertions(+), 20 deletions(-). The main changes are: 1) Explicitly memset the bpf_attr structure on bpf() syscall to avoid having to rely on compiler to do so. Issues have been noticed on some compilers with padding and other oddities where the request was then unexpectedly rejected, from Greg Kroah-Hartman. 2) Sanitize the bpf_struct_ops TCP congestion control name in order to avoid problematic characters such as whitespaces, from Martin KaFai Lau. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-27tracing: Create set_event_notrace_pid to not trace tasksSteven Rostedt (VMware)
There's currently a way to select a task that should only have its events traced, but there's no way to select a task not to have itsevents traced. Add a set_event_notrace_pid file that acts the same as set_event_pid (and is also affected by event-fork), but the task pids in this file will not be traced even if they are listed in the set_event_pid file. This makes it easy for tools like trace-cmd to "hide" itself from beint traced by events when it is recording other tasks. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-27ftrace: Create set_ftrace_notrace_pid to not trace tasksSteven Rostedt (VMware)
There's currently a way to select a task that should only be traced by functions, but there's no way to select a task not to be traced by the function tracer. Add a set_ftrace_notrace_pid file that acts the same as set_ftrace_pid (and is also affected by function-fork), but the task pids in this file will not be traced even if they are listed in the set_ftrace_pid file. This makes it easy for tools like trace-cmd to "hide" itself from the function tracer when it is recording other tasks. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-27ftrace: Make function trace pid filtering a bit more exactSteven Rostedt (VMware)
The set_ftrace_pid file is used to filter function tracing to only trace tasks that are listed in that file. Instead of testing the pids listed in that file (it's a bitmask) at each function trace event, the logic is done via a sched_switch hook. A flag is set when the next task to run is in the list of pids in the set_ftrace_pid file. But the sched_switch hook is not at the exact location of when the task switches, and the flag gets set before the task to be traced actually runs. This leaves a residue of traced functions that do not belong to the pid that should be filtered on. By changing the logic slightly, where instead of having a boolean flag to test, record the pid that should be traced, with special values for not to trace and always trace. Then at each function call, a check will be made to see if the function should be ignored, or if the current pid matches the function that should be traced, and only trace if it matches (or if it has the special value to always trace). Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-27ftrace/kprobe: Show the maxactive number on kprobe_eventsMasami Hiramatsu
Show maxactive parameter on kprobe_events. This allows user to save the current configuration and restore it without losing maxactive parameter. Link: http://lkml.kernel.org/r/4762764a-6df7-bc93-ed60-e336146dce1f@gmail.com Link: http://lkml.kernel.org/r/158503528846.22706.5549974121212526020.stgit@devnote2 Cc: stable@vger.kernel.org Fixes: 696ced4fb1d76 ("tracing/kprobes: expose maxactive for kretprobe in kprobe_events") Reported-by: Taeung Song <treeze.taeung@gmail.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-27ring-buffer/tracing: Have iterator acknowledge dropped eventsSteven Rostedt (VMware)
Have the ring_buffer_iterator set a flag if events were dropped as it were to go and peek at the next event. Have the trace file display this fact if it happened with a "LOST EVENTS" message. Link: http://lkml.kernel.org/r/20200317213417.045858900@goodmis.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-27tracing: Do not disable tracing when reading the trace fileSteven Rostedt (VMware)
When opening the "trace" file, it is no longer necessary to disable tracing. Note, a new option is created called "pause-on-trace", when set, will cause the trace file to emulate its original behavior. Link: http://lkml.kernel.org/r/20200317213416.903351225@goodmis.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-27ring-buffer: Do not disable recording when there is an iteratorSteven Rostedt (VMware)
Now that the iterator can handle a concurrent writer, do not disable writing to the ring buffer when there is an iterator present. Link: http://lkml.kernel.org/r/20200317213416.759770696@goodmis.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-27ring-buffer: Make resize disable per cpu buffer instead of total bufferSteven Rostedt (VMware)
When the ring buffer becomes writable for even when the trace file is read, it must still not be resized. But since tracers can be activated while the trace file is being read, the irqsoff tracer can modify the per CPU buffers, and this can cause the reader of the trace file to update the wrong buffer's resize disable bit, as the irqsoff tracer swaps out cpu buffers. By making the resize disable per cpu_buffer, it makes the update follow the per cpu_buffer even if it's swapped out with the snapshot buffer and keeps the release of the trace file modifying the same data as the open did. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-27perf/core: Add PERF_SAMPLE_CGROUP featureNamhyung Kim
The PERF_SAMPLE_CGROUP bit is to save (perf_event) cgroup information in the sample. It will add a 64-bit id to identify current cgroup and it's the file handle in the cgroup file system. Userspace should use this information with PERF_RECORD_CGROUP event to match which cgroup it belongs. I put it before PERF_SAMPLE_AUX for simplicity since it just needs a 64-bit word. But if we want bigger samples, I can work on that direction too. Committer testing: $ pahole perf_sample_data | grep -w cgroup -B5 -A5 /* --- cacheline 4 boundary (256 bytes) was 56 bytes ago --- */ struct perf_regs regs_intr; /* 312 16 */ /* --- cacheline 5 boundary (320 bytes) was 8 bytes ago --- */ u64 stack_user_size; /* 328 8 */ u64 phys_addr; /* 336 8 */ u64 cgroup; /* 344 8 */ /* size: 384, cachelines: 6, members: 22 */ /* padding: 32 */ }; $ Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Tejun Heo <tj@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Zefan Li <lizefan@huawei.com> Link: http://lore.kernel.org/lkml/20200325124536.2800725-3-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-03-27perf/core: Add PERF_RECORD_CGROUP eventNamhyung Kim
To support cgroup tracking, add CGROUP event to save a link between cgroup path and id number. This is needed since cgroups can go away when userspace tries to read the cgroup info (from the id) later. The attr.cgroup bit was also added to enable cgroup tracking from userspace. This event will be generated when a new cgroup becomes active. Userspace might need to synthesize those events for existing cgroups. Committer testing: From the resulting kernel, using /sys/kernel/btf/vmlinux: $ pahole perf_event_attr | grep -w cgroup -B5 -A1 __u64 write_backward:1; /* 40:27 8 */ __u64 namespaces:1; /* 40:28 8 */ __u64 ksymbol:1; /* 40:29 8 */ __u64 bpf_event:1; /* 40:30 8 */ __u64 aux_output:1; /* 40:31 8 */ __u64 cgroup:1; /* 40:32 8 */ __u64 __reserved_1:31; /* 40:33 8 */ $ Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Tejun Heo <tj@kernel.org> [staticize perf_event_cgroup function] Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Zefan Li <lizefan@huawei.com> Link: http://lore.kernel.org/lkml/20200325124536.2800725-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-03-26bpf: Remove unused vairable 'bpf_xdp_link_lops'YueHaibing
kernel/bpf/syscall.c:2263:34: warning: 'bpf_xdp_link_lops' defined but not used [-Wunused-const-variable=] static const struct bpf_link_ops bpf_xdp_link_lops; ^~~~~~~~~~~~~~~~~ commit 70ed506c3bbc ("bpf: Introduce pinnable bpf_link abstraction") involded this unused variable, remove it. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200326031613.19372-1-yuehaibing@huawei.com
2020-03-26bpf: Factor out attach_type to prog_type mapping for attach/detachAndrii Nakryiko
Factor out logic mapping expected program attach type to program type and subsequent handling of program attach/detach. Also list out all supported cgroup BPF program types explicitly to prevent accidental bugs once more program types are added to a mapping. Do the same for prog_query API. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200325065746.640559-3-andriin@fb.com
2020-03-26bpf: Factor out cgroup storages operationsAndrii Nakryiko
Refactor cgroup attach/detach code to abstract away common operations performed on all types of cgroup storages. This makes high-level logic more apparent, plus allows to reuse more code across multiple functions. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200325065746.640559-2-andriin@fb.com
2020-03-25bpf: Verifer, adjust_scalar_min_max_vals to always call update_reg_bounds()John Fastabend
Currently, for all op verification we call __red_deduce_bounds() and __red_bound_offset() but we only call __update_reg_bounds() in bitwise ops. However, we could benefit from calling __update_reg_bounds() in BPF_ADD, BPF_SUB, and BPF_MUL cases as well. For example, a register with state 'R1_w=invP0' when we subtract from it, w1 -= 2 Before coerce we will now have an smin_value=S64_MIN, smax_value=U64_MAX and unsigned bounds umin_value=0, umax_value=U64_MAX. These will then be clamped to S32_MIN, U32_MAX values by coerce in the case of alu32 op as done in above example. However tnum will be a constant because the ALU op is done on a constant. Without update_reg_bounds() we have a scenario where tnum is a const but our unsigned bounds do not reflect this. By calling update_reg_bounds after coerce to 32bit we further refine the umin_value to U64_MAX in the alu64 case or U32_MAX in the alu32 case above. Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/158507151689.15666.566796274289413203.stgit@john-Precision-5820-Tower
2020-03-25bpf: Verifer, refactor adjust_scalar_min_max_valsJohn Fastabend
Pull per op ALU logic into individual functions. We are about to add u32 versions of each of these by pull them out the code gets a bit more readable here and nicer in the next patch. Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/158507149518.15666.15672349629329072411.stgit@john-Precision-5820-Tower
2020-03-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Overlapping header include additions in macsec.c A bug fix in 'net' overlapping with the removal of 'version' string in ena_netdev.c Overlapping test additions in selftests Makefile Overlapping PCI ID table adjustments in iwlwifi driver. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds
Pull networking fixes from David Miller: 1) Fix deadlock in bpf_send_signal() from Yonghong Song. 2) Fix off by one in kTLS offload of mlx5, from Tariq Toukan. 3) Add missing locking in iwlwifi mvm code, from Avraham Stern. 4) Fix MSG_WAITALL handling in rxrpc, from David Howells. 5) Need to hold RTNL mutex in tcindex_partial_destroy_work(), from Cong Wang. 6) Fix producer race condition in AF_PACKET, from Willem de Bruijn. 7) cls_route removes the wrong filter during change operations, from Cong Wang. 8) Reject unrecognized request flags in ethtool netlink code, from Michal Kubecek. 9) Need to keep MAC in reset until PHY is up in bcmgenet driver, from Doug Berger. 10) Don't leak ct zone template in act_ct during replace, from Paul Blakey. 11) Fix flushing of offloaded netfilter flowtable flows, also from Paul Blakey. 12) Fix throughput drop during tx backpressure in cxgb4, from Rahul Lakkireddy. 13) Don't let a non-NULL skb->dev leave the TCP stack, from Eric Dumazet. 14) TCP_QUEUE_SEQ socket option has to update tp->copied_seq as well, also from Eric Dumazet. 15) Restrict macsec to ethernet devices, from Willem de Bruijn. 16) Fix reference leak in some ethtool *_SET handlers, from Michal Kubecek. 17) Fix accidental disabling of MSI for some r8169 chips, from Heiner Kallweit. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (138 commits) net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} build net: ena: Add PCI shutdown handler to allow safe kexec selftests/net/forwarding: define libs as TEST_PROGS_EXTENDED selftests/net: add missing tests to Makefile r8169: re-enable MSI on RTL8168c net: phy: mdio-bcm-unimac: Fix clock handling cxgb4/ptp: pass the sign of offset delta in FW CMD net: dsa: tag_8021q: replace dsa_8021q_remove_header with __skb_vlan_pop net: cbs: Fix software cbs to consider packet sending time net/mlx5e: Do not recover from a non-fatal syndrome net/mlx5e: Fix ICOSQ recovery flow with Striding RQ net/mlx5e: Fix missing reset of SW metadata in Striding RQ reset net/mlx5e: Enhance ICOSQ WQE info fields net/mlx5_core: Set IB capability mask1 to fix ib_srpt connection failure selftests: netfilter: add nfqueue test case netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress netfilter: nft_fwd_netdev: validate family and chain type netfilter: nft_set_rbtree: Detect partial overlaps on insertion netfilter: nft_set_rbtree: Introduce and use nft_rbtree_interval_start() netfilter: nft_set_pipapo: Separate partial and complete overlap cases on insertion ...
2020-03-25pidfd: Use new infrastructure to fix deadlocks in execveBernd Edlinger
This changes __pidfd_fget to use the new exec_update_mutex instead of cred_guard_mutex. This should be safe, as the credentials do not change before exec_update_mutex is locked. Therefore whatever file access is possible with holding the cred_guard_mutex here is also possbile with the exec_update_mutex. Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-03-25perf: Use new infrastructure to fix deadlocks in execveBernd Edlinger
This changes perf_event_set_clock to use the new exec_update_mutex instead of cred_guard_mutex. This should be safe, as the credentials are only used for reading. Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-03-25kernel/kcmp.c: Use new infrastructure to fix deadlocks in execveBernd Edlinger
This changes kcmp_epoll_target to use the new exec_update_mutex instead of cred_guard_mutex. This should be safe, as the credentials are only used for reading, and furthermore ->mm and ->sighand are updated on execve, but only under the new exec_update_mutex. Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-03-25kernel: doc: remove outdated comment cred.cBernd Edlinger
This removes an outdated comment in prepare_kernel_cred. There is no "cred_replace_mutex" any more, so the comment must go away. Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-03-25exec: Fix a deadlock in straceBernd Edlinger
This fixes a deadlock in the tracer when tracing a multi-threaded application that calls execve while more than one thread are running. I observed that when running strace on the gcc test suite, it always blocks after a while, when expect calls execve, because other threads have to be terminated. They send ptrace events, but the strace is no longer able to respond, since it is blocked in vm_access. The deadlock is always happening when strace needs to access the tracees process mmap, while another thread in the tracee starts to execve a child process, but that cannot continue until the PTRACE_EVENT_EXIT is handled and the WIFEXITED event is received: strace D 0 30614 30584 0x00000000 Call Trace: __schedule+0x3ce/0x6e0 schedule+0x5c/0xd0 schedule_preempt_disabled+0x15/0x20 __mutex_lock.isra.13+0x1ec/0x520 __mutex_lock_killable_slowpath+0x13/0x20 mutex_lock_killable+0x28/0x30 mm_access+0x27/0xa0 process_vm_rw_core.isra.3+0xff/0x550 process_vm_rw+0xdd/0xf0 __x64_sys_process_vm_readv+0x31/0x40 do_syscall_64+0x64/0x220 entry_SYSCALL_64_after_hwframe+0x44/0xa9 expect D 0 31933 30876 0x80004003 Call Trace: __schedule+0x3ce/0x6e0 schedule+0x5c/0xd0 flush_old_exec+0xc4/0x770 load_elf_binary+0x35a/0x16c0 search_binary_handler+0x97/0x1d0 __do_execve_file.isra.40+0x5d4/0x8a0 __x64_sys_execve+0x49/0x60 do_syscall_64+0x64/0x220 entry_SYSCALL_64_after_hwframe+0x44/0xa9 This changes mm_access to use the new exec_update_mutex instead of cred_guard_mutex. This patch is based on the following patch by Eric W. Biederman: "[PATCH 0/5] Infrastructure to allow fixing exec deadlocks" Link: https://lore.kernel.org/lkml/87v9ne5y4y.fsf_-_@x220.int.ebiederm.org/ Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-03-25exec: Add exec_update_mutex to replace cred_guard_mutexEric W. Biederman
The cred_guard_mutex is problematic as it is held over possibly indefinite waits for userspace. The possible indefinite waits for userspace that I have identified are: The cred_guard_mutex is held in PTRACE_EVENT_EXIT waiting for the tracer. The cred_guard_mutex is held over "put_user(0, tsk->clear_child_tid)" in exit_mm(). The cred_guard_mutex is held over "get_user(futex_offset, ...") in exit_robust_list. The cred_guard_mutex held over copy_strings. The functions get_user and put_user can trigger a page fault which can potentially wait indefinitely in the case of userfaultfd or if userspace implements part of the page fault path. In any of those cases the userspace process that the kernel is waiting for might make a different system call that winds up taking the cred_guard_mutex and result in deadlock. Holding a mutex over any of those possibly indefinite waits for userspace does not appear necessary. Add exec_update_mutex that will just cover updating the process during exec where the permissions and the objects pointed to by the task struct may be out of sync. The plan is to switch the users of cred_guard_mutex to exec_update_mutex one by one. This lets us move forward while still being careful and not introducing any regressions. Link: https://lore.kernel.org/lkml/20160921152946.GA24210@dhcp22.suse.cz/ Link: https://lore.kernel.org/lkml/AM6PR03MB5170B06F3A2B75EFB98D071AE4E60@AM6PR03MB5170.eurprd03.prod.outlook.com/ Link: https://lore.kernel.org/linux-fsdevel/20161102181806.GB1112@redhat.com/ Link: https://lore.kernel.org/lkml/20160923095031.GA14923@redhat.com/ Link: https://lore.kernel.org/lkml/20170213141452.GA30203@redhat.com/ Ref: 45c1a159b85b ("Add PTRACE_O_TRACEVFORKDONE and PTRACE_O_TRACEEXIT facilities.") Ref: 456f17cd1a28 ("[PATCH] user-vm-unlock-2.5.31-A2") Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-03-25cpu/hotplug: Hide cpu_up/down()Qais Yousef
Use separate functions for the device core to bring a CPU up and down. Users outside the device core must use add/remove_cpu() which will take care of extra housekeeping work like keeping sysfs in sync. Make cpu_up/down() static and replace the extra layer of indirection. [ tglx: Removed the extra wrapper functions and adjusted function names ] Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200323135110.30522-18-qais.yousef@arm.com
2020-03-25cpu/hotplug: Move bringup of secondary CPUs out of smp_init()Qais Yousef
This is the last direct user of cpu_up() before it can become an internal implementation detail of the cpu subsystem. Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200323135110.30522-17-qais.yousef@arm.com
2020-03-25torture: Replace cpu_up/down() with add/remove_cpu()Qais Yousef
The core device API performs extra housekeeping bits that are missing from directly calling cpu_up/down(). See commit a6717c01ddc2 ("powerpc/rtas: use device model APIs and serialization during LPM") for an example description of what might go wrong. This also prepares to make cpu_up/down() a private interface of the CPU subsystem. Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: "Paul E. McKenney" <paulmck@kernel.org> Link: https://lkml.kernel.org/r/20200323135110.30522-16-qais.yousef@arm.com
2020-03-25cpu/hotplug: Provide bringup_hibernate_cpu()Qais Yousef
arm64 uses cpu_up() in the resume from hibernation code to ensure that the CPU on which the system hibernated is online. Provide a core function for this. [ tglx: Split out from the combo arm64 patch ] Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/20200323135110.30522-9-qais.yousef@arm.com
2020-03-25cpu/hotplug: Create a new function to shutdown nonboot cpusQais Yousef
This function will be used later in machine_shutdown() for some architectures. disable_nonboot_cpus() is not safe to use when doing machine_down(), because it relies on freeze_secondary_cpus() which in turn is a suspend/resume related freeze and could abort if the logic detects any pending activities that can prevent finishing the offlining process. Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200323135110.30522-3-qais.yousef@arm.com
2020-03-25cpu/hotplug: Add new {add,remove}_cpu() functionsQais Yousef
The new functions use device_{online,offline}() which are userspace safe. This is in preparation to move cpu_{up, down} kernel users to use a safer interface that is not racy with userspace. Suggested-by: "Paul E. McKenney" <paulmck@kernel.org> Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lkml.kernel.org/r/20200323135110.30522-2-qais.yousef@arm.com
2020-03-25.gitignore: add SPDX License IdentifierMasahiro Yamada
Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25.gitignore: remove too obvious commentsMasahiro Yamada
Some .gitignore files have comments like "Generated files", "Ignore generated files" at the header part, but they are too obvious. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24Merge branch 'for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU changes from Paul E. McKenney: - Make kfree_rcu() use kfree_bulk() for added performance - RCU updates - Callback-overload handling updates - Tasks-RCU KCSAN and sparse updates - Locking torture test and RCU torture test updates - Documentation updates - Miscellaneous fixes Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-23completion: Use lockdep_assert_RT_in_threaded_ctx() in complete_all()Sebastian Siewior
The warning was intended to spot complete_all() users from hardirq context on PREEMPT_RT. The warning as-is will also trigger in interrupt handlers, which are threaded on PREEMPT_RT, which was not intended. Use lockdep_assert_RT_in_threaded_ctx() which triggers in non-preemptive context on PREEMPT_RT. Fixes: a5c6234e1028 ("completion: Use simple wait queues") Reported-by: kernel test robot <rong.a.chen@intel.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200323152019.4qjwluldohuh3by5@linutronix.de
2020-03-23fsnotify: use helpers to access data by data_typeAmir Goldstein
Create helpers to access path and inode from different data types. Link: https://lore.kernel.org/r/20200319151022.31456-5-amir73il@gmail.com Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-23PM: remove s390 specific callbacksHeiko Carstens
ARCH_SAVE_PAGE_KEYS has been introduced in order to be able to save and restore s390 specific storage keys into a hibernation image. With hibernation support removed from s390 there is no point in keeping the callbacks. Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-03-23Merge 5.6-rc7 into tty-nextGreg Kroah-Hartman
We need the tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-23Merge 5.6-rc7 into char-misc-nextGreg Kroah-Hartman
We need the char/misc driver fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-21x86/mm: split vmalloc_sync_all()Joerg Roedel
Commit 3f8fd02b1bf1 ("mm/vmalloc: Sync unmappings in __purge_vmap_area_lazy()") introduced a call to vmalloc_sync_all() in the vunmap() code-path. While this change was necessary to maintain correctness on x86-32-pae kernels, it also adds additional cycles for architectures that don't need it. Specifically on x86-64 with CONFIG_VMAP_STACK=y some people reported severe performance regressions in micro-benchmarks because it now also calls the x86-64 implementation of vmalloc_sync_all() on vunmap(). But the vmalloc_sync_all() implementation on x86-64 is only needed for newly created mappings. To avoid the unnecessary work on x86-64 and to gain the performance back, split up vmalloc_sync_all() into two functions: * vmalloc_sync_mappings(), and * vmalloc_sync_unmappings() Most call-sites to vmalloc_sync_all() only care about new mappings being synchronized. The only exception is the new call-site added in the above mentioned commit. Shile Zhang directed us to a report of an 80% regression in reaim throughput. Fixes: 3f8fd02b1bf1 ("mm/vmalloc: Sync unmappings in __purge_vmap_area_lazy()") Reported-by: kernel test robot <oliver.sang@intel.com> Reported-by: Shile Zhang <shile.zhang@linux.alibaba.com> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Borislav Petkov <bp@suse.de> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [GHES] Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20191009124418.8286-1-joro@8bytes.org Link: https://lists.01.org/hyperkitty/list/lkp@lists.01.org/thread/4D3JPPHBNOSPFK2KEPC6KGKS6J25AIDB/ Link: http://lkml.kernel.org/r/20191113095530.228959-1-shile.zhang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-21Merge branches 'doc.2020.02.27a', 'fixes.2020.03.21a', ↵Paul E. McKenney
'kfree_rcu.2020.02.20a', 'locktorture.2020.02.20a', 'ovld.2020.02.20a', 'rcu-tasks.2020.02.20a', 'srcu.2020.02.20a' and 'torture.2020.02.20a' into HEAD doc.2020.02.27a: Documentation updates. fixes.2020.03.21a: Miscellaneous fixes. kfree_rcu.2020.02.20a: Updates to kfree_rcu(). locktorture.2020.02.20a: Lock torture-test updates. ovld.2020.02.20a: Updates to callback-overload handling. rcu-tasks.2020.02.20a: RCU-tasks updates. srcu.2020.02.20a: SRCU updates. torture.2020.02.20a: Torture-test updates.
2020-03-21rcu: Make rcu_barrier() account for offline no-CBs CPUsPaul E. McKenney
Currently, rcu_barrier() ignores offline CPUs, However, it is possible for an offline no-CBs CPU to have callbacks queued, and rcu_barrier() must wait for those callbacks. This commit therefore makes rcu_barrier() directly invoke the rcu_barrier_func() with interrupts disabled for such CPUs. This requires passing the CPU number into this function so that it can entrain the rcu_barrier() callback onto the correct CPU's callback list, given that the code must instead execute on the current CPU. While in the area, this commit fixes a bug where the first CPU's callback might have been invoked before rcu_segcblist_entrain() returned, which would also result in an early wakeup. Fixes: 5d6742b37727 ("rcu/nocb: Use rcu_segcblist for no-CBs CPUs") Signed-off-by: Paul E. McKenney <paulmck@kernel.org> [ paulmck: Apply optimization feedback from Boqun Feng. ] Cc: <stable@vger.kernel.org> # 5.5.x
2020-03-21rcu: Mark rcu_state.gp_seq to detect concurrent writesPaul E. McKenney
The rcu_state structure's gp_seq field is only to be modified by the RCU grace-period kthread, which is single-threaded. This commit therefore enlists KCSAN's help in enforcing this restriction. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>