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2018-06-12treewide: kzalloc_node() -> kcalloc_node()Kees Cook
The kzalloc_node() function has a 2-factor argument form, kcalloc_node(). This patch replaces cases of: kzalloc_node(a * b, gfp, node) with: kcalloc_node(a * b, gfp, node) as well as handling cases of: kzalloc_node(a * b * c, gfp, node) with: kzalloc_node(array3_size(a, b, c), gfp, node) as it's slightly less ugly than: kcalloc_node(array_size(a, b), c, gfp, node) This does, however, attempt to ignore constant size factors like: kzalloc_node(4 * 1024, gfp, node) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc_node( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc_node( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc_node( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc_node( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc_node( - sizeof(char) * COUNT + COUNT , ...) | kzalloc_node( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc_node + kcalloc_node ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc_node( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc_node( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc_node( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc_node( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc_node( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc_node( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc_node( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc_node( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc_node( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc_node( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc_node( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc_node(C1 * C2 * C3, ...) | kzalloc_node( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc_node( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc_node( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc_node( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc_node(sizeof(THING) * C2, ...) | kzalloc_node(sizeof(TYPE) * C2, ...) | kzalloc_node(C1 * C2 * C3, ...) | kzalloc_node(C1 * C2, ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - (E1) * E2 + E1, E2 , ...) | - kzalloc_node + kcalloc_node ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc_node + kcalloc_node ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12treewide: kzalloc() -> kcalloc()Kees Cook
The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: 1) Add Maglev hashing scheduler to IPVS, from Inju Song. 2) Lots of new TC subsystem tests from Roman Mashak. 3) Add TCP zero copy receive and fix delayed acks and autotuning with SO_RCVLOWAT, from Eric Dumazet. 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard Brouer. 5) Add ttl inherit support to vxlan, from Hangbin Liu. 6) Properly separate ipv6 routes into their logically independant components. fib6_info for the routing table, and fib6_nh for sets of nexthops, which thus can be shared. From David Ahern. 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP messages from XDP programs. From Nikita V. Shirokov. 8) Lots of long overdue cleanups to the r8169 driver, from Heiner Kallweit. 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau. 10) Add traffic condition monitoring to iwlwifi, from Luca Coelho. 11) Plumb extack down into fib_rules, from Roopa Prabhu. 12) Add Flower classifier offload support to igb, from Vinicius Costa Gomes. 13) Add UDP GSO support, from Willem de Bruijn. 14) Add documentation for eBPF helpers, from Quentin Monnet. 15) Add TLS tx offload to mlx5, from Ilya Lesokhin. 16) Allow applications to be given the number of bytes available to read on a socket via a control message returned from recvmsg(), from Soheil Hassas Yeganeh. 17) Add x86_32 eBPF JIT compiler, from Wang YanQing. 18) Add AF_XDP sockets, with zerocopy support infrastructure as well. From Björn Töpel. 19) Remove indirect load support from all of the BPF JITs and handle these operations in the verifier by translating them into native BPF instead. From Daniel Borkmann. 20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha. 21) Allow XDP programs to do lookups in the main kernel routing tables for forwarding. From David Ahern. 22) Allow drivers to store hardware state into an ELF section of kernel dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy. 23) Various RACK and loss detection improvements in TCP, from Yuchung Cheng. 24) Add TCP SACK compression, from Eric Dumazet. 25) Add User Mode Helper support and basic bpfilter infrastructure, from Alexei Starovoitov. 26) Support ports and protocol values in RTM_GETROUTE, from Roopa Prabhu. 27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard Brouer. 28) Add lots of forwarding selftests, from Petr Machata. 29) Add generic network device failover driver, from Sridhar Samudrala. * ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits) strparser: Add __strp_unpause and use it in ktls. rxrpc: Fix terminal retransmission connection ID to include the channel net: hns3: Optimize PF CMDQ interrupt switching process net: hns3: Fix for VF mailbox receiving unknown message net: hns3: Fix for VF mailbox cannot receiving PF response bnx2x: use the right constant Revert "net: sched: cls: Fix offloading when ingress dev is vxlan" net: dsa: b53: Fix for brcm tag issue in Cygnus SoC enic: fix UDP rss bits netdev-FAQ: clarify DaveM's position for stable backports rtnetlink: validate attributes in do_setlink() mlxsw: Add extack messages for port_{un, }split failures netdevsim: Add extack error message for devlink reload devlink: Add extack to reload and port_{un, }split operations net: metrics: add proper netlink validation ipmr: fix error path when ipmr_new_table fails ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds net: hns3: remove unused hclgevf_cfg_func_mta_filter netfilter: provide udp*_lib_lookup for nf_tproxy qed*: Utilize FW 8.37.2.0 ...
2018-05-25perf/core: Wire up compat PERF_EVENT_IOC_QUERY_BPF, ↵Eugene Syromiatnikov
PERF_EVENT_IOC_MODIFY_ATTRIBUTES Since pointer size is different in compat, and switching in _perf_ioctl is done using exact ioctl numbers, all new ioctl numbers that use pointer should be added to perf_compat_ioctl for _IOC_SIZE fixup before passing to perf_ioctl routine (this shouldn't be needed if semantics of the size argument of _IO* macros was honored). Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> 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> Link: http://lkml.kernel.org/r/20180521123420.GA24291@asgard.redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-25perf/core: Fix bad use of igrab()Song Liu
As Miklos reported and suggested: "This pattern repeats two times in trace_uprobe.c and in kernel/events/core.c as well: ret = kern_path(filename, LOOKUP_FOLLOW, &path); if (ret) goto fail_address_parse; inode = igrab(d_inode(path.dentry)); path_put(&path); And it's wrong. You can only hold a reference to the inode if you have an active ref to the superblock as well (which is normally through path.mnt) or holding s_umount. This way unmounting the containing filesystem while the tracepoint is active will give you the "VFS: Busy inodes after unmount..." message and a crash when the inode is finally put. Solution: store path instead of inode." This patch fixes the issue in kernel/event/core.c. Reviewed-and-tested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reported-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <kernel-team@fb.com> 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: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 375637bc5249 ("perf/core: Introduce address range filtering") Link: http://lkml.kernel.org/r/20180418062907.3210386-2-songliubraving@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-25perf/core: Fix group scheduling with mixed hw and sw eventsSong Liu
When hw and sw events are mixed in the same group, they are all attached to the hw perf_event_context. This sometimes requires moving group of perf_event to a different context. We found a bug in how the kernel handles this, for example if we do: perf stat -e '{faults,ref-cycles,faults}' -I 1000 1.005591180 1,297 faults 1.005591180 457,476,576 ref-cycles 1.005591180 <not supported> faults First, sw event "faults" is attached to the sw context, and becomes the group leader. Then, hw event "ref-cycles" is attached, so both events are moved to the hw context. Last, another sw "faults" tries to attach, but it fails because of mismatch between the new target ctx (from sw pmu) and the group_leader's ctx (hw context, same as ref-cycles). The broken condition is: group_leader is sw event; group_leader is on hw context; add a sw event to the group. Fix this scenario by checking group_leader's context (instead of just event type). If group_leader is on hw context, use the ->pmu of this context to look up context for the new event. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <kernel-team@fb.com> 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: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: b04243ef7006 ("perf: Complete software pmu grouping") Link: http://lkml.kernel.org/r/20180503194716.162815-1-songliubraving@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Alexei Starovoitov says: ==================== pull-request: bpf-next 2018-05-24 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Björn Töpel cleans up AF_XDP (removes rebind, explicit cache alignment from uapi, etc). 2) David Ahern adds mtu checks to bpf_ipv{4,6}_fib_lookup() helpers. 3) Jesper Dangaard Brouer adds bulking support to ndo_xdp_xmit. 4) Jiong Wang adds support for indirect and arithmetic shifts to NFP 5) Martin KaFai Lau cleans up BTF uapi and makes the btf_header extensible. 6) Mathieu Xhonneux adds an End.BPF action to seg6local with BPF helpers allowing to edit/grow/shrink a SRH and apply on a packet generic SRv6 actions. 7) Sandipan Das adds support for bpf2bpf function calls in ppc64 JIT. 8) Yonghong Song adds BPF_TASK_FD_QUERY command for introspection of tracing events. 9) other misc fixes from Gustavo A. R. Silva, Sirio Balmelli, John Fastabend, and Magnus Karlsson ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-24perf/core: add perf_get_event() to return perf_event given a struct fileYonghong Song
A new extern function, perf_get_event(), is added to return a perf event given a struct file. This function will be used in later patches. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-05perf/core: Fix possible Spectre-v1 indexing for ->aux_pages[]Peter Zijlstra
> kernel/events/ring_buffer.c:871 perf_mmap_to_page() warn: potential spectre issue 'rb->aux_pages' Userspace controls @pgoff through the fault address. Sanitize the array index before doing the array dereference. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@kernel.org> 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: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-02Merge tag 'trace-v4.17-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Various fixes in tracing: - Tracepoints should not give warning on OOM failures - Use special field for function pointer in trace event - Fix igrab issues in uprobes - Fixes to the new histogram triggers" * tag 'trace-v4.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracepoint: Do not warn on ENOMEM tracing: Add field modifier parsing hist error for hist triggers tracing: Add field parsing hist error for hist triggers tracing: Restore proper field flag printing when displaying triggers tracing: initcall: Ordered comparison of function pointers tracing: Remove igrab() iput() call from uprobes.c tracing: Fix bad use of igrab in trace_uprobe.c
2018-04-26tracing: Remove igrab() iput() call from uprobes.cSong Liu
Caller of uprobe_register is required to keep the inode and containing mount point referenced. There was misuse of igrab() in uprobes.c and trace_uprobe.c. This is because igrab() will not prevent umount of the containing mount point. To fix this, we added path to struct trace_uprobe, which keeps the inode and containing mount reference. For uprobes.c, it is not necessary to call igrab() in uprobe_register(), as the caller is required to keep the inode reference. The igrab() is removed and comments on this requirement is added to uprobe_register(). Link: http://lkml.kernel.org/r/CAELBmZB2XX=qEOLAdvGG4cPx4GEntcSnWQquJLUK1ongRj35cA@mail.gmail.com Link: http://lkml.kernel.org/r/20180423172135.4050588-2-songliubraving@fb.com Cc: Ingo Molnar <mingo@redhat.com> Cc: Howard McLauchlan <hmclauchlan@fb.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-17perf: Remove superfluous allocation error checkJiri Olsa
If the get_callchain_buffers fails to allocate the buffer it will decrease the nr_callchain_events right away. There's no point of checking the allocation error for nr_callchain_events > 1. Removing that check. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: syzkaller-bugs@googlegroups.com Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20180415092352.12403-3-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-17perf: Fix sample_max_stack maximum checkJiri Olsa
The syzbot hit KASAN bug in perf_callchain_store having the entry stored behind the allocated bounds [1]. We miss the sample_max_stack check for the initial event that allocates callchain buffers. This missing check allows to create an event with sample_max_stack value bigger than the global sysctl maximum: # sysctl -a | grep perf_event_max_stack kernel.perf_event_max_stack = 127 # perf record -vv -C 1 -e cycles/max-stack=256/ kill ... perf_event_attr: size 112 ... sample_max_stack 256 ------------------------------------------------------------ sys_perf_event_open: pid -1 cpu 1 group_fd -1 flags 0x8 = 4 Note the '-C 1', which forces perf record to create just single event. Otherwise it opens event for every cpu, then the sample_max_stack check fails on the second event and all's fine. The fix is to run the sample_max_stack check also for the first event with callchains. [1] https://marc.info/?l=linux-kernel&m=152352732920874&w=2 Reported-by: syzbot+7c449856228b63ac951e@syzkaller.appspotmail.com Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: syzkaller-bugs@googlegroups.com Cc: x86@kernel.org Fixes: 97c79a38cd45 ("perf core: Per event callchain limit") Link: http://lkml.kernel.org/r/20180415092352.12403-2-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-17perf: Return proper values for user stack errorsJiri Olsa
Return immediately when we find issue in the user stack checks. The error value could get overwritten by following check for PERF_SAMPLE_REGS_INTR. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: syzkaller-bugs@googlegroups.com Cc: x86@kernel.org Fixes: 60e2364e60e8 ("perf: Add ability to sample machine state on interrupt") Link: http://lkml.kernel.org/r/20180415092352.12403-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-17perf/core: Store context switch out type in PERF_RECORD_SWITCH[_CPU_WIDE]Alexey Budankov
Store preempting context switch out event into Perf trace as a part of PERF_RECORD_SWITCH[_CPU_WIDE] record. Percentage of preempting and non-preempting context switches help understanding the nature of workloads (CPU or IO bound) that are running on a machine; The event is treated as preemption one when task->state value of the thread being switched out is TASK_RUNNING. Event type encoding is implemented using PERF_RECORD_MISC_SWITCH_OUT_PREEMPT bit; Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/9ff84e83-a0ca-dd82-a6d0-cb951689be74@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-12perf/core: Need CAP_SYS_ADMIN to create k/uprobe with perf_event_open()Song Liu
Non-root user cannot create kprobe or uprobe through the text-based interface (kprobe_events, uprobe_events),so they should not be able to create probes via perf_event_open() either. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Song Liu <songliubraving@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 33ea4b24277b ("perf/core: Implement the 'perf_uprobe' PMU") Fixes: e12f03d7031a ("perf/core: Implement the 'perf_kprobe' PMU") Link: http://lkml.kernel.org/r/C0B2EFB5-C403-4BDB-9046-C14B3EE66999@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-09perf/core: Fix use-after-free in uprobe_perf_close()Prashant Bhole
A use-after-free bug was caught by KASAN while running usdt related code (BCC project. bcc/tests/python/test_usdt2.py): ================================================================== BUG: KASAN: use-after-free in uprobe_perf_close+0x222/0x3b0 Read of size 4 at addr ffff880384f9b4a4 by task test_usdt2.py/870 CPU: 4 PID: 870 Comm: test_usdt2.py Tainted: G W 4.16.0-next-20180409 #215 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 Call Trace: dump_stack+0xc7/0x15b ? show_regs_print_info+0x5/0x5 ? printk+0x9c/0xc3 ? kmsg_dump_rewind_nolock+0x6e/0x6e ? uprobe_perf_close+0x222/0x3b0 print_address_description+0x83/0x3a0 ? uprobe_perf_close+0x222/0x3b0 kasan_report+0x1dd/0x460 ? uprobe_perf_close+0x222/0x3b0 uprobe_perf_close+0x222/0x3b0 ? probes_open+0x180/0x180 ? free_filters_list+0x290/0x290 trace_uprobe_register+0x1bb/0x500 ? perf_event_attach_bpf_prog+0x310/0x310 ? probe_event_disable+0x4e0/0x4e0 perf_uprobe_destroy+0x63/0xd0 _free_event+0x2bc/0xbd0 ? lockdep_rcu_suspicious+0x100/0x100 ? ring_buffer_attach+0x550/0x550 ? kvm_sched_clock_read+0x1a/0x30 ? perf_event_release_kernel+0x3e4/0xc00 ? __mutex_unlock_slowpath+0x12e/0x540 ? wait_for_completion+0x430/0x430 ? lock_downgrade+0x3c0/0x3c0 ? lock_release+0x980/0x980 ? do_raw_spin_trylock+0x118/0x150 ? do_raw_spin_unlock+0x121/0x210 ? do_raw_spin_trylock+0x150/0x150 perf_event_release_kernel+0x5d4/0xc00 ? put_event+0x30/0x30 ? fsnotify+0xd2d/0xea0 ? sched_clock_cpu+0x18/0x1a0 ? __fsnotify_update_child_dentry_flags.part.0+0x1b0/0x1b0 ? pvclock_clocksource_read+0x152/0x2b0 ? pvclock_read_flags+0x80/0x80 ? kvm_sched_clock_read+0x1a/0x30 ? sched_clock_cpu+0x18/0x1a0 ? pvclock_clocksource_read+0x152/0x2b0 ? locks_remove_file+0xec/0x470 ? pvclock_read_flags+0x80/0x80 ? fcntl_setlk+0x880/0x880 ? ima_file_free+0x8d/0x390 ? lockdep_rcu_suspicious+0x100/0x100 ? ima_file_check+0x110/0x110 ? fsnotify+0xea0/0xea0 ? kvm_sched_clock_read+0x1a/0x30 ? rcu_note_context_switch+0x600/0x600 perf_release+0x21/0x40 __fput+0x264/0x620 ? fput+0xf0/0xf0 ? do_raw_spin_unlock+0x121/0x210 ? do_raw_spin_trylock+0x150/0x150 ? SyS_fchdir+0x100/0x100 ? fsnotify+0xea0/0xea0 task_work_run+0x14b/0x1e0 ? task_work_cancel+0x1c0/0x1c0 ? copy_fd_bitmaps+0x150/0x150 ? vfs_read+0xe5/0x260 exit_to_usermode_loop+0x17b/0x1b0 ? trace_event_raw_event_sys_exit+0x1a0/0x1a0 do_syscall_64+0x3f6/0x490 ? syscall_return_slowpath+0x2c0/0x2c0 ? lockdep_sys_exit+0x1f/0xaa ? syscall_return_slowpath+0x1a3/0x2c0 ? lockdep_sys_exit+0x1f/0xaa ? prepare_exit_to_usermode+0x11c/0x1e0 ? enter_from_user_mode+0x30/0x30 random: crng init done ? __put_user_4+0x1c/0x30 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x7f41d95f9340 RSP: 002b:00007fffe71e4268 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 000000000000000d RCX: 00007f41d95f9340 RDX: 0000000000000000 RSI: 0000000000002401 RDI: 000000000000000d RBP: 0000000000000000 R08: 00007f41ca8ff700 R09: 00007f41d996dd1f R10: 00007fffe71e41e0 R11: 0000000000000246 R12: 00007fffe71e4330 R13: 0000000000000000 R14: fffffffffffffffc R15: 00007fffe71e4290 Allocated by task 870: kasan_kmalloc+0xa0/0xd0 kmem_cache_alloc_node+0x11a/0x430 copy_process.part.19+0x11a0/0x41c0 _do_fork+0x1be/0xa20 do_syscall_64+0x198/0x490 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Freed by task 0: __kasan_slab_free+0x12e/0x180 kmem_cache_free+0x102/0x4d0 free_task+0xfe/0x160 __put_task_struct+0x189/0x290 delayed_put_task_struct+0x119/0x250 rcu_process_callbacks+0xa6c/0x1b60 __do_softirq+0x238/0x7ae The buggy address belongs to the object at ffff880384f9b480 which belongs to the cache task_struct of size 12928 It occurs because task_struct is freed before perf_event which refers to the task and task flags are checked while teardown of the event. perf_event_alloc() assigns task_struct to hw.target of perf_event, but there is no reference counting for it. As a fix we get_task_struct() in perf_event_alloc() at above mentioned assignment and put_task_struct() in _free_event(). Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 63b6da39bb38e8f1a1ef3180d32a39d6 ("perf: Fix perf_event_exit_task() race") Link: http://lkml.kernel.org/r/20180409100346.6416-1-bhole_prashant_q7@lab.ntt.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-29perf/x86/pt, coresight: Clean up address filter structureAlexander Shishkin
This is a cosmetic patch that deals with the address filter structure's ambiguous fields 'filter' and 'range'. The former stands to mean that the filter's *action* should be to filter the traces to its address range if it's set or stop tracing if it's unset. This is confusing and hard on the eyes, so this patch replaces it with 'action' enum. The 'range' field is completely redundant (meaning that the filter is an address range as opposed to a single address trigger), as we can use zero size to mean the same thing. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org> Acked-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: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/20180329120648.11902-1-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-29Merge branch 'perf/urgent' into perf/coreIngo Molnar
Conflicts: kernel/events/hw_breakpoint.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-28perf/hwbp: Simplify the perf-hwbp code, fix documentationLinus Torvalds
Annoyingly, modify_user_hw_breakpoint() unnecessarily complicates the modification of a breakpoint - simplify it and remove the pointless local variables. Also update the stale Docbook while at it. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-24Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar
With the cherry-picked perf/urgent commit merged separately we can now merge all the fixes without conflicts. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-20perf/cgroup: Fix child event counting bugSong Liu
When a perf_event is attached to parent cgroup, it should count events for all children cgroups: parent_group <---- perf_event \ - child_group <---- process(es) However, in our tests, we found this perf_event cannot report reliable results. Here is an example case: # create cgroups mkdir -p /sys/fs/cgroup/p/c # start perf for parent group perf stat -e instructions -G "p" # on another console, run test process in child cgroup: stressapptest -s 2 -M 1000 & echo $! > /sys/fs/cgroup/p/c/cgroup.procs # after the test process is done, stop perf in the first console shows <not counted> instructions p The instruction should not be "not counted" as the process runs in the child cgroup. We found this is because perf_event->cgrp and cpuctx->cgrp are not identical, thus perf_event->cgrp are not updated properly. This patch fixes this by updating perf_cgroup properly for ancestor cgroup(s). Reported-by: Ephraim Park <ephiepark@fb.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <jolsa@redhat.com> Cc: <kernel-team@fb.com> 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: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/20180312165943.1057894-1-songliubraving@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-19Merge tag 'v4.16-rc6' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-16perf/core: Clear sibling list of detached eventsMark Rutland
When perf_group_dettach() is called on a group leader, it updates each sibling's group_leader field to point to that sibling, effectively upgrading each siblnig to a group leader. After perf_group_detach has completed, the caller may free the leader event. We only remove siblings from the group leader's sibling_list when the leader has a non-empty group_node. This was fine prior to commit: 8343aae66167df67 ("perf/core: Remove perf_event::group_entry") ... as the sibling's sibling_list would be empty. However, now that we use the sibling_list field as both the list head and the list entry, this leaves each sibling with a non-empty sibling list, including the stale leader event. If perf_group_detach() is subsequently called on a sibling, it will appear to be a group leader, and we'll walk the sibling_list, potentially dereferencing these stale events. In 0day testing, this has been observed to result in kernel panics. Let's avoid this by always removing siblings from the sibling list when we promote them to leaders. Fixes: 8343aae66167df67 ("perf/core: Remove perf_event::group_entry") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: vincent.weaver@maine.edu Cc: Peter Zijlstra <peterz@infradead.org> Cc: torvalds@linux-foundation.org Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: valery.cherepennikov@intel.com Cc: linux-tip-commits@vger.kernel.org Cc: eranian@google.com Cc: acme@redhat.com Cc: alexander.shishkin@linux.intel.com Cc: davidcc@google.com Cc: kan.liang@intel.com Cc: Dmitry.Prohorov@intel.com Cc: Jiri Olsa <jolsa@redhat.com> Link: https://lkml.kernel.org/r/20180316131741.3svgr64yibc6vsid@lakrids.cambridge.arm.com
2018-03-16perf: Fix sibling iterationPeter Zijlstra
Mark noticed that the change to sibling_list changed some iteration semantics; because previously we used group_list as list entry, sibling events would always have an empty sibling_list. But because we now use sibling_list for both list head and list entry, siblings will report as having siblings. Fix this with a custom for_each_sibling_event() iterator. Fixes: 8343aae66167 ("perf/core: Remove perf_event::group_entry") Reported-by: Mark Rutland <mark.rutland@arm.com> Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: vincent.weaver@maine.edu Cc: alexander.shishkin@linux.intel.com Cc: torvalds@linux-foundation.org Cc: alexey.budankov@linux.intel.com Cc: valery.cherepennikov@intel.com Cc: eranian@google.com Cc: acme@redhat.com Cc: linux-tip-commits@vger.kernel.org Cc: davidcc@google.com Cc: kan.liang@intel.com Cc: Dmitry.Prohorov@intel.com Cc: jolsa@redhat.com Link: https://lkml.kernel.org/r/20180315170129.GX4043@hirez.programming.kicks-ass.net
2018-03-13perf/core: Implement fast breakpoint modification via _IOC_MODIFY_ATTRIBUTESMilind Chabbi
Problem and motivation: Once a breakpoint perf event (PERF_TYPE_BREAKPOINT) is created, there is no flexibility to change the breakpoint type (bp_type), breakpoint address (bp_addr), or breakpoint length (bp_len). The only option is to close the perf event and configure a new breakpoint event. This inflexibility has a significant performance overhead. For example, sampling-based, lightweight performance profilers (and also concurrency bug detection tools), monitor different addresses for a short duration using PERF_TYPE_BREAKPOINT and change the address (bp_addr) to another address or change the kind of breakpoint (bp_type) from "write" to a "read" or vice-versa or change the length (bp_len) of the address being monitored. The cost of these modifications is prohibitive since it involves unmapping the circular buffer associated with the perf event, closing the perf event, opening another perf event and mmaping another circular buffer. Solution: The new ioctl flag for perf events, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, introduced in this patch takes a pointer to a struct perf_event_attr as an argument to update an old breakpoint event with new address, type, and size. This facility allows retaining a previous mmaped perf events ring buffer and avoids having to close and reopen another perf event. This patch supports only changing PERF_TYPE_BREAKPOINT event type; future implementations can extend this feature. The patch replicates some of its functionality of modify_user_hw_breakpoint() in kernel/events/hw_breakpoint.c. modify_user_hw_breakpoint cannot be called directly since perf_event_ctx_lock() is already held in _perf_ioctl(). Evidence: Experiments show that the baseline (not able to modify an already created breakpoint) costs an order of magnitude (~10x) more than the suggested optimization (having the ability to dynamically modifying a configured breakpoint via ioctl). When the breakpoints typically do not trap, the speedup due to the suggested optimization is ~10x; even when the breakpoints always trap, the speedup is ~4x due to the suggested optimization. Testing: tests posted at https://github.com/linux-contrib/perf_event_modify_bp demonstrate the performance significance of this patch. Tests also check the functional correctness of the patch. Signed-off-by: Milind Chabbi <chabbi.milind@gmail.com> [ Using modify_user_hw_breakpoint_check function. ] [ Reformated PERF_EVENT_IOC_*, so the values are all in one column. ] Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Oleg Nesterov <onestero@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/20180312134548.31532-8-jolsa@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-13perf/core: Move perf_event_attr::sample_max_stack into perf_copy_attr()Jiri Olsa
Move the sample_max_stack check and setup into perf_copy_attr(), so we have all perf_event_attr initial setup in one place and can easily compare attrs in the new ioctl introduced in following change. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Milind Chabbi <chabbi.milind@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Oleg Nesterov <onestero@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/20180312134548.31532-7-jolsa@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-13hw_breakpoint: Add perf_event_attr fields check in __modify_user_hw_breakpoint()Jiri Olsa
And rename it to modify_user_hw_breakpoint_check(). We are about to use modify_user_hw_breakpoint_check() for user space breakpoints modification, we must be very strict to check only the fields we can change have changed. As Peter explained: "Suppose someone does: attr = malloc(sizeof(*attr)); // uninitialized memory attr->type = BP; attr->bp_addr = new_addr; attr->bp_type = bp_type; attr->bp_len = bp_len; ioctl(fd, PERF_IOC_MOD_ATTR, &attr); And feeds absolute shite for the rest of the fields. Then we later want to extend IOC_MOD_ATTR to allow changing attr::sample_type but we can't, because that would break the above application." I'm making this check optional because we already export modify_user_hw_breakpoint() and with this check we could break existing users. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Milind Chabbi <chabbi.milind@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Oleg Nesterov <onestero@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/20180312134548.31532-6-jolsa@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-13hw_breakpoint: Factor out __modify_user_hw_breakpoint() functionJiri Olsa
Moving out all the functionality without the events disabling/enabling calls, because we want to call another disabling/enabling functions in following change. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Milind Chabbi <chabbi.milind@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Oleg Nesterov <onestero@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/20180312134548.31532-5-jolsa@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-13hw_breakpoint: Add modify_bp_slot() functionJiri Olsa
Add the modify_bp_slot() function to keep slot numbers correct when changing the breakpoint type. Using existing __release_bp_slot()/__reserve_bp_slot() call sequence to update the slot counts. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Milind Chabbi <chabbi.milind@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Oleg Nesterov <onestero@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@l