user/sven/linux.git/kernel/trace, branch v3.7.4

ring-buffer: Fix race between integrity check and readers

2012-12-17T19:07:24Z

commit 9366c1ba13fbc41bdb57702e75ca4382f209c82f upstream. The function rb_check_pages() was added to make sure the ring buffer's pages were sane. This check is done when the ring buffer size is modified as well as when the iterator is released (closing the "trace" file), as that was considered a non fast path and a good place to do a sanity check. The problem is that the check does not have any locks around it. If one process were to read the trace file, and another were to read the raw binary file, the check could happen while the reader is reading the file. The issues with this is that the check requires to clear the HEAD page before doing the full check and it restores it afterward. But readers require the HEAD page to exist before it can read the buffer, otherwise it gives a nasty warning and disables the buffer. By adding the reader lock around the check, this keeps the race from happening. Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

ring-buffer: Fix NULL pointer if rb_set_head_page() fails

2012-12-17T19:07:23Z

commit 54f7be5b831254199522523ccab4c3d954bbf576 upstream. The function rb_set_head_page() searches the list of ring buffer pages for a the page that has the HEAD page flag set. If it does not find it, it will do a WARN_ON(), disable the ring buffer and return NULL, as this should never happen. But if this bug happens to happen, not all callers of this function can handle a NULL pointer being returned from it. That needs to be fixed. Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

ftrace: Clear bits properly in reset_iter_read()

2012-12-17T19:07:22Z

commit 70f77b3f7ec010ff9624c1f2e39a81babc9e2429 upstream. There is a typo here where '&' is used instead of '|' and it turns the statement into a noop. The original code is equivalent to: iter->flags &= ~((1 << 2) & (1 << 4)); Link: http://lkml.kernel.org/r/20120609161027.GD6488@elgon.mountain Signed-off-by: Dan Carpenter Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

Merge branch 'tip/perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/urgent

2012-10-21T17:53:34Z

Pull ftrace ring-buffer resizing fix from Steve Rostedt. Signed-off-by: Ingo Molnar

ring-buffer: Check for uninitialized cpu buffer before resizing

2012-10-11T16:21:48Z

With a system where, num_present_cpus < num_possible_cpus, even if all CPUs are online, non-present CPUs don't have per_cpu buffers allocated. If per_cpu//buffer_size_kb is modified for such a CPU, it can cause a panic due to NULL dereference in ring_buffer_resize(). To fix this, resize operation is allowed only if the per-cpu buffer has been initialized. Link: http://lkml.kernel.org/r/1349912427-6486-1-git-send-email-vnagarnaik@google.com Cc: stable@vger.kernel.org # 3.5+ Signed-off-by: Vaibhav Nagarnaik Signed-off-by: Steven Rostedt

Merge branch 'virtio-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

2012-10-07T12:04:56Z

Pull virtio changes from Rusty Russell: "New workflow: same git trees pulled by linux-next get sent straight to Linus. Git is awkward at shuffling patches compared with quilt or mq, but that doesn't happen often once things get into my -next branch." * 'virtio-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (24 commits) lguest: fix occasional crash in example launcher. virtio-blk: Disable callback in virtblk_done() virtio_mmio: Don't attempt to create empty virtqueues virtio_mmio: fix off by one error allocating queue drivers/virtio/virtio_pci.c: fix error return code virtio: don't crash when device is buggy virtio: remove CONFIG_VIRTIO_RING virtio: add help to CONFIG_VIRTIO option. virtio: support reserved vqs virtio: introduce an API to set affinity for a virtqueue virtio-ring: move queue_index to vring_virtqueue virtio_balloon: not EXPERIMENTAL any more. virtio-balloon: dependency fix virtio-blk: fix NULL checking in virtblk_alloc_req() virtio-blk: Add REQ_FLUSH and REQ_FUA support to bio path virtio-blk: Add bio-based IO path for virtio-blk virtio: console: fix error handling in init() function tools: Fix pthread flag for Makefile of trace-agent used by virtio-trace tools: Add guest trace agent as a user tool virtio/console: Allocate scatterlist according to the current pipe size ...

Merge tag 'for-v3.7' of git://git.infradead.org/users/cbou/linux-pstore

2012-10-07T08:30:50Z

Pull pstore changes from Anton Vorontsov: 1) We no longer ad-hoc to the function tracer "high level" infrastructure and no longer use its debugfs knobs. The change slightly touches kernel/trace directory, but it got the needed ack from Steven Rostedt: http://lkml.org/lkml/2012/8/21/688 2) Added maintainers entry; 3) A bunch of fixes, nothing special. * tag 'for-v3.7' of git://git.infradead.org/users/cbou/linux-pstore: pstore: Avoid recursive spinlocks in the oops_in_progress case pstore/ftrace: Convert to its own enable/disable debugfs knob pstore/ram: Add missing platform_device_unregister MAINTAINERS: Add pstore maintainers pstore/ram: Mark ramoops_pstore_write_buf() as notrace pstore/ram: Fix printk format warning pstore/ram: Fix possible NULL dereference

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2012-10-02T18:11:09Z

Pull user namespace changes from Eric Biederman: "This is a mostly modest set of changes to enable basic user namespace support. This allows the code to code to compile with user namespaces enabled and removes the assumption there is only the initial user namespace. Everything is converted except for the most complex of the filesystems: autofs4, 9p, afs, ceph, cifs, coda, fuse, gfs2, ncpfs, nfs, ocfs2 and xfs as those patches need a bit more review. The strategy is to push kuid_t and kgid_t values are far down into subsystems and filesystems as reasonable. Leaving the make_kuid and from_kuid operations to happen at the edge of userspace, as the values come off the disk, and as the values come in from the network. Letting compile type incompatible compile errors (present when user namespaces are enabled) guide me to find the issues. The most tricky areas have been the places where we had an implicit union of uid and gid values and were storing them in an unsigned int. Those places were converted into explicit unions. I made certain to handle those places with simple trivial patches. Out of that work I discovered we have generic interfaces for storing quota by projid. I had never heard of the project identifiers before. Adding full user namespace support for project identifiers accounts for most of the code size growth in my git tree. Ultimately there will be work to relax privlige checks from "capable(FOO)" to "ns_capable(user_ns, FOO)" where it is safe allowing root in a user names to do those things that today we only forbid to non-root users because it will confuse suid root applications. While I was pushing kuid_t and kgid_t changes deep into the audit code I made a few other cleanups. I capitalized on the fact we process netlink messages in the context of the message sender. I removed usage of NETLINK_CRED, and started directly using current->tty. Some of these patches have also made it into maintainer trees, with no problems from identical code from different trees showing up in linux-next. After reading through all of this code I feel like I might be able to win a game of kernel trivial pursuit." Fix up some fairly trivial conflicts in netfilter uid/git logging code. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (107 commits) userns: Convert the ufs filesystem to use kuid/kgid where appropriate userns: Convert the udf filesystem to use kuid/kgid where appropriate userns: Convert ubifs to use kuid/kgid userns: Convert squashfs to use kuid/kgid where appropriate userns: Convert reiserfs to use kuid and kgid where appropriate userns: Convert jfs to use kuid/kgid where appropriate userns: Convert jffs2 to use kuid and kgid where appropriate userns: Convert hpfs to use kuid and kgid where appropriate userns: Convert btrfs to use kuid/kgid where appropriate userns: Convert bfs to use kuid/kgid where appropriate userns: Convert affs to use kuid/kgid wherwe appropriate userns: On alpha modify linux_to_osf_stat to use convert from kuids and kgids userns: On ia64 deal with current_uid and current_gid being kuid and kgid userns: On ppc convert current_uid from a kuid before printing. userns: Convert s390 getting uid and gid system calls to use kuid and kgid userns: Convert s390 hypfs to use kuid and kgid where appropriate userns: Convert binder ipc to use kuids userns: Teach security_path_chown to take kuids and kgids userns: Add user namespace support to IMA userns: Convert EVM to deal with kuids and kgids in it's hmac computation ...

ftrace: Allow stealing pages from pipe buffer

2012-09-28T05:35:12Z

Use generic steal operation on pipe buffer to allow stealing ring buffer's read page from pipe buffer. Note that this could reduce the performance of splice on the splice_write side operation without affinity setting. Since the ring buffer's read pages are allocated on the tracing-node, but the splice user does not always execute splice write side operation on the same node. In this case, the page will be accessed from the another node. Thus, it is strongly recommended to assign the splicing thread to corresponding node. Signed-off-by: Masami Hiramatsu Acked-by: Steven Rostedt Signed-off-by: Rusty Russell

trace: Move trace event enable from fs_initcall to core_initcall

2012-09-24T18:13:02Z

This patch splits trace event initialization in two stages: * ftrace enable * sysfs event entry creation This allows to capture trace events from an earlier point by using 'trace_event' kernel parameter and is important to trace boot-up allocations. Note that, in order to enable events at core_initcall, it's necessary to move init_ftrace_syscalls() from core_initcall to early_initcall. Link: http://lkml.kernel.org/r/1347461277-25302-1-git-send-email-elezegarcia@gmail.com Signed-off-by: Ezequiel Garcia Signed-off-by: Steven Rostedt