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2012-06-21UBUNTU: SAUCE: SECCOMP: ptrace,seccomp: Add PTRACE_SECCOMP supportWill Drewry
This change adds support for a new ptrace option, PTRACE_O_TRACESECCOMP, and a new return value for seccomp BPF programs, SECCOMP_RET_TRACE. When a tracer specifies the PTRACE_O_TRACESECCOMP ptrace option, the tracer will be notified, via PTRACE_EVENT_SECCOMP, for any syscall that results in a BPF program returning SECCOMP_RET_TRACE. The 16-bit SECCOMP_RET_DATA mask of the BPF program return value will be passed as the ptrace_message and may be retrieved using PTRACE_GETEVENTMSG. If the subordinate process is not using seccomp filter, then no system call notifications will occur even if the option is specified. If there is no tracer with PTRACE_O_TRACESECCOMP when SECCOMP_RET_TRACE is returned, the system call will not be executed and an -ENOSYS errno will be returned to userspace. This change adds a dependency on the system call slow path. Any future efforts to use the system call fast path for seccomp filter will need to address this restriction. v16: - update PT_TRACE_MASK to 0xbf4 so that STOP isn't clear on SETOPTIONS call (indan@nul.nu) [note PT_TRACE_MASK disappears in linux-next] v15: - add audit support for non-zero return codes - clean up style (indan@nul.nu) v14: - rebase/nochanges v13: - rebase on to 88ebdda6159ffc15699f204c33feb3e431bf9bdc (Brings back a change to ptrace.c and the masks.) v12: - rebase to linux-next - use ptrace_event and update arch/Kconfig to mention slow-path dependency - drop all tracehook changes and inclusion (oleg@redhat.com) v11: - invert the logic to just make it a PTRACE_SYSCALL accelerator (indan@nul.nu) v10: - moved to PTRACE_O_SECCOMP / PT_TRACE_SECCOMP v9: - n/a v8: - guarded PTRACE_SECCOMP use with an ifdef v7: - introduced Signed-off-by: Will Drewry <wad@chromium.org> Signed-off-by: Kees Cook <kees@ubuntu.com>
2012-06-21UBUNTU: SAUCE: SECCOMP: seccomp: Add SECCOMP_RET_TRAPWill Drewry
Adds a new return value to seccomp filters that triggers a SIGSYS to be delivered with the new SYS_SECCOMP si_code. This allows in-process system call emulation, including just specifying an errno or cleanly dumping core, rather than just dying. v15: - use audit_seccomp/skip - pad out error spacing; clean up switch (indan@nul.nu) v14: - n/a v13: - rebase on to 88ebdda6159ffc15699f204c33feb3e431bf9bdc v12: - rebase on to linux-next v11: - clarify the comment (indan@nul.nu) - s/sigtrap/sigsys v10: - use SIGSYS, syscall_get_arch, updates arch/Kconfig note suggested-by (though original suggestion had other behaviors) v9: - changes to SIGILL v8: - clean up based on changes to dependent patches v7: - introduction Suggested-by: Markus Gutschke <markus@chromium.org> Suggested-by: Julien Tinnes <jln@chromium.org> Signed-off-by: Will Drewry <wad@chromium.org> Signed-off-by: Kees Cook <kees@ubuntu.com>
2012-06-21UBUNTU: SAUCE: SECCOMP: signal, x86: add SIGSYS info and make it synchronous.Will Drewry
This change enables SIGSYS, defines _sigfields._sigsys, and adds x86 (compat) arch support. _sigsys defines fields which allow a signal handler to receive the triggering system call number, the relevant AUDIT_ARCH_* value for that number, and the address of the callsite. SIGSYS is added to the SYNCHRONOUS_MASK because it is desirable for it to have setup_frame() called for it. The goal is to ensure that ucontext_t reflects the machine state from the time-of-syscall and not from another signal handler. The first consumer of SIGSYS would be seccomp filter. In particular, a filter program could specify a new return value, SECCOMP_RET_TRAP, which would result in the system call being denied and the calling thread signaled. This also means that implementing arch-specific support can be dependent upon HAVE_ARCH_SECCOMP_FILTER. v14: - rebase/nochanges v13: - rebase on to 88ebdda6159ffc15699f204c33feb3e431bf9bdc v12: - reworded changelog (oleg@redhat.com) v11: - fix dropped words in the change description - added fallback copy_siginfo support. - added __ARCH_SIGSYS define to allow stepped arch support. v10: - first version based on suggestion Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Will Drewry <wad@chromium.org> Signed-off-by: Kees Cook <kees@ubuntu.com>
2012-06-21UBUNTU: SAUCE: SECCOMP: seccomp: add SECCOMP_RET_ERRNOWill Drewry
This change adds the SECCOMP_RET_ERRNO as a valid return value from a seccomp filter. Additionally, it makes the first use of the lower 16-bits for storing a filter-supplied errno. 16-bits is more than enough for the errno-base.h calls. Returning errors instead of immediately terminating processes that violate seccomp policy allow for broader use of this functionality for kernel attack surface reduction. For example, a linux container could maintain a whitelist of pre-existing system calls but drop all new ones with errnos. This would keep a logically static attack surface while providing errnos that may allow for graceful failure without the downside of do_exit() on a bad call. v15: - use audit_seccomp and add a skip label. (eparis@redhat.com) - clean up and pad out return codes (indan@nul.nu) v14: - no change/rebase v13: - rebase on to 88ebdda6159ffc15699f204c33feb3e431bf9bdc v12: - move to WARN_ON if filter is NULL (oleg@redhat.com, luto@mit.edu, keescook@chromium.org) - return immediately for filter==NULL (keescook@chromium.org) - change evaluation to only compare the ACTION so that layered errnos don't result in the lowest one being returned. (keeschook@chromium.org) v11: - check for NULL filter (keescook@chromium.org) v10: - change loaders to fn v9: - n/a v8: - update Kconfig to note new need for syscall_set_return_value. - reordered such that TRAP behavior follows on later. - made the for loop a little less indent-y v7: - introduced Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Will Drewry <wad@chromium.org> Signed-off-by: Kees Cook <kees@ubuntu.com>
2012-06-21UBUNTU: SAUCE: SECCOMP: seccomp: remove duplicated failure loggingKees Cook
This consolidates the seccomp filter error logging path and adds more details to the audit log. v15: added a return code to the audit_seccomp path by wad@chromium.org (suggested by eparis@redhat.com) v*: original by keescook@chromium.org Signed-off-by: Will Drewry <wad@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <kees@ubuntu.com>
2012-06-21UBUNTU: SAUCE: SECCOMP: seccomp: add system call filtering using BPFWill Drewry
[This patch depends on luto@mit.edu's no_new_privs patch: https://lkml.org/lkml/2012/1/30/264 The whole series including Andrew's patches can be found here: https://github.com/redpig/linux/tree/seccomp Complete diff here: https://github.com/redpig/linux/compare/1dc65fed...seccomp A GPG signed tag 'seccomp/v14/posted' will be pushed shortly. ] This patch adds support for seccomp mode 2. Mode 2 introduces the ability for unprivileged processes to install system call filtering policy expressed in terms of a Berkeley Packet Filter (BPF) program. This program will be evaluated in the kernel for each system call the task makes and computes a result based on data in the format of struct seccomp_data. A filter program may be installed by calling: struct sock_fprog fprog = { ... }; ... prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &fprog); The return value of the filter program determines if the system call is allowed to proceed or denied. If the first filter program installed allows prctl(2) calls, then the above call may be made repeatedly by a task to further reduce its access to the kernel. All attached programs must be evaluated before a system call will be allowed to proceed. Filter programs will be inherited across fork/clone and execve. However, if the task attaching the filter is unprivileged (!CAP_SYS_ADMIN) the no_new_privs bit will be set on the task. This ensures that unprivileged tasks cannot attach filters that affect privileged tasks (e.g., setuid binary). There are a number of benefits to this approach. A few of which are as follows: - BPF has been exposed to userland for a long time - BPF optimization (and JIT'ing) are well understood - Userland already knows its ABI: system call numbers and desired arguments - No time-of-check-time-of-use vulnerable data accesses are possible. - system call arguments are loaded on access only to minimize copying required for system call policy decisions. Mode 2 support is restricted to architectures that enable HAVE_ARCH_SECCOMP_FILTER. In this patch, the primary dependency is on syscall_get_arguments(). The full desired scope of this feature will add a few minor additional requirements expressed later in this series. Based on discussion, SECCOMP_RET_ERRNO and SECCOMP_RET_TRACE seem to be the desired additional functionality. No architectures are enabled in this patch. v15: - add a 4 instr penalty when counting a path to account for seccomp_filter size (indan@nul.nu) - drop the max insns to 256KB (indan@nul.nu) - return ENOMEM if the max insns limit has been hit (indan@nul.nu) - move IP checks after args (indan@nul.nu) - drop !user_filter check (indan@nul.nu) - only allow explicit bpf codes (indan@nul.nu) - exit_code -> exit_sig v14: - put/get_seccomp_filter takes struct task_struct (indan@nul.nu,keescook@chromium.org) - adds seccomp_chk_filter and drops general bpf_run/chk_filter user - add seccomp_bpf_load for use by net/core/filter.c - lower max per-process/per-hierarchy: 1MB - moved nnp/capability check prior to allocation (all of the above: indan@nul.nu) v13: - rebase on to 88ebdda6159ffc15699f204c33feb3e431bf9bdc v12: - added a maximum instruction count per path (indan@nul.nu,oleg@redhat.com) - removed copy_seccomp (keescook@chromium.org,indan@nul.nu) - reworded the prctl_set_seccomp comment (indan@nul.nu) v11: - reorder struct seccomp_data to allow future args expansion (hpa@zytor.com) - style clean up, @compat dropped, compat_sock_fprog32 (indan@nul.nu) - do_exit(SIGSYS) (keescook@chromium.org, luto@mit.edu) - pare down Kconfig doc reference. - extra comment clean up v10: - seccomp_data has changed again to be more aesthetically pleasing (hpa@zytor.com) - calling convention is noted in a new u32 field using syscall_get_arch. This allows for cross-calling convention tasks to use seccomp filters. (hpa@zytor.com) - lots of clean up (thanks, Indan!) v9: - n/a v8: - use bpf_chk_filter, bpf_run_filter. update load_fns - Lots of fixes courtesy of indan@nul.nu: -- fix up load behavior, compat fixups, and merge alloc code, -- renamed pc and dropped __packed, use bool compat. -- Added a hidden CONFIG_SECCOMP_FILTER to synthesize non-arch dependencies v7: (massive overhaul thanks to Indan, others) - added CONFIG_HAVE_ARCH_SECCOMP_FILTER - merged into seccomp.c - minimal seccomp_filter.h - no config option (part of seccomp) - no new prctl - doesn't break seccomp on systems without asm/syscall.h (works but arg access always fails) - dropped seccomp_init_task, extra free functions, ... - dropped the no-asm/syscall.h code paths - merges with network sk_run_filter and sk_chk_filter v6: - fix memory leak on attach compat check failure - require no_new_privs || CAP_SYS_ADMIN prior to filter installation. (luto@mit.edu) - s/seccomp_struct_/seccomp_/ for macros/functions (amwang@redhat.com) - cleaned up Kconfig (amwang@redhat.com) - on block, note if the call was compat (so the # means something) v5: - uses syscall_get_arguments (indan@nul.nu,oleg@redhat.com, mcgrathr@chromium.org) - uses union-based arg storage with hi/lo struct to handle endianness. Compromises between the two alternate proposals to minimize extra arg shuffling and account for endianness assuming userspace uses offsetof(). (mcgrathr@chromium.org, indan@nul.nu) - update Kconfig description - add include/seccomp_filter.h and add its installation - (naive) on-demand syscall argument loading - drop seccomp_t (eparis@redhat.com) v4: - adjusted prctl to make room for PR_[SG]ET_NO_NEW_PRIVS - now uses current->no_new_privs (luto@mit.edu,torvalds@linux-foundation.com) - assign names to seccomp modes (rdunlap@xenotime.net) - fix style issues (rdunlap@xenotime.net) - reworded Kconfig entry (rdunlap@xenotime.net) v3: - macros to inline (oleg@redhat.com) - init_task behavior fixed (oleg@redhat.com) - drop creator entry and extra NULL check (oleg@redhat.com) - alloc returns -EINVAL on bad sizing (serge.hallyn@canonical.com) - adds tentative use of "always_unprivileged" as per torvalds@linux-foundation.org and luto@mit.edu v2: - (patch 2 only) Reviewed-by: Indan Zupancic <indan@nul.nu> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Will Drewry <wad@chromium.org> Signed-off-by: Kees Cook <kees@ubuntu.com>
2012-06-21UBUNTU: SAUCE: SECCOMP: Add PR_{GET,SET}_NO_NEW_PRIVS to prevent execve from ↵Andy Lutomirski
granting privs With this set, a lot of dangerous operations (chroot, unshare, etc) become a lot less dangerous because there is no possibility of subverting privileged binaries. This patch completely breaks apparmor. Someone who understands (and uses) apparmor should fix it or at least give me a hint. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Kees Cook <kees@ubuntu.com>
2012-06-21UBUNTU: SAUCE: add option to hand off all kernel parameters to initAndy Whitcroft
BugLink: http://bugs.launchpad.net/bugs/586386 Some init packages such as upstart find having all of the kernel parameters passed in useful. Currently they have to open up /proc/cmdline and reparse that to obtain this information. Add a kernel configuration option to enable passing of all options. Note, enabling this option will reduce the chances that a fallback from /sbin/init to /bin/bash or /bin/sh will succeed. Though it should be noted that there are commonly unknown options present which would already break this fallback. init=/bin/foo provides explicit control over options which is unaffected by this change. Signed-off-by: Andy Whitcroft <apw@canonical.com> Signed-off-by: Leann Ogasawara <leann.ogasawara@canonical.com>
2012-05-17Merge branches 'perf-urgent-for-linus', 'x86-urgent-for-linus' and ↵Linus Torvalds
'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf, x86 and scheduler updates from Ingo Molnar. * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tracing: Do not enable function event with enable perf stat: handle ENXIO error for perf_event_open perf: Turn off compiler warnings for flex and bison generated files perf stat: Fix case where guest/host monitoring is not supported by kernel perf build-id: Fix filename size calculation * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, kvm: KVM paravirt kernels don't check for CPUID being unavailable x86: Fix section annotation of acpi_map_cpu2node() x86/microcode: Ensure that module is only loaded on supported Intel CPUs * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Fix KVM and ia64 boot crash due to sched_groups circular linked list assumption
2012-05-15genirq: export handle_edge_irq() and irq_to_desc()Jiri Kosina
Export handle_edge_irq() and irq_to_desc() to modules to allow them to do things such as __irq_set_handler_locked(...., handle_edge_irq); This fixes ERROR: "handle_edge_irq" [drivers/gpio/gpio-pch.ko] undefined! ERROR: "irq_to_desc" [drivers/gpio/gpio-pch.ko] undefined! when gpio-pch is being built as a module. This was introduced by commit df9541a60af0 ("gpio: pch9: Use proper flow type handlers") that added __irq_set_handler_locked(d->irq, handle_edge_irq); but handle_edge_irq() was not exported for modules (and inlined __irq_set_handler_locked() requires irq_to_desc() exported as well) Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-10namespaces, pid_ns: fix leakage on fork() failureMike Galbraith
Fork() failure post namespace creation for a child cloned with CLONE_NEWPID leaks pid_namespace/mnt_cache due to proc being mounted during creation, but not unmounted during cleanup. Call pid_ns_release_proc() during cleanup. Signed-off-by: Mike Galbraith <efault@gmx.de> Acked-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Louis Rilling <louis.rilling@kerlabs.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-10tracing: Do not enable function event with enableSteven Rostedt
With the adding of function tracing event to perf, it caused a side effect that produces the following warning when enabling all events in ftrace: # echo 1 > /sys/kernel/debug/tracing/events/enable [console] event trace: Could not enable event function This is because when enabling all events via the debugfs system it ignores events that do not have a ->reg() function assigned. This was to skip over the ftrace internal events (as they are not TRACE_EVENTs). But as the ftrace function event now has a ->reg() function attached to it for use with perf, it is no longer ignored. Worse yet, this ->reg() function is being called when it should not be. It returns an error and causes the above warning to be printed. By adding a new event_call flag (TRACE_EVENT_FL_IGNORE_ENABLE) and have all ftrace internel event structures have it set, setting the events/enable will no longe try to incorrectly enable the function event and does not warn. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-05-10compat: Fix RT signal mask corruption via sigprocmaskJan Kiszka
compat_sys_sigprocmask reads a smaller signal mask from userspace than sigprogmask accepts for setting. So the high word of blocked.sig[0] will be cleared, releasing any potentially blocked RT signal. This was discovered via userspace code that relies on get/setcontext. glibc's i386 versions of those functions use sigprogmask instead of rt_sigprogmask to save/restore signal mask and caused RT signal unblocking this way. As suggested by Linus, this replaces the sys_sigprocmask based compat version with one that open-codes the required logic, including the merge of the existing blocked set with the new one provided on SIG_SETMASK. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-09sched: Fix KVM and ia64 boot crash due to sched_groups circular linked list ↵Igor Mammedov
assumption If we have one cpu that failed to boot and boot cpu gave up on waiting for it and then another cpu is being booted, kernel might crash with following OOPS: BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 IP: [<ffffffff812c3630>] __bitmap_weight+0x30/0x80 Call Trace: [<ffffffff8108b9b6>] build_sched_domains+0x7b6/0xa50 The crash happens in init_sched_groups_power() that expects sched_groups to be circular linked list. However it is not always true, since sched_groups preallocated in __sdt_alloc are initialized in build_sched_groups and it may exit early if (cpu != cpumask_first(sched_domain_span(sd))) return 0; without initializing sd->groups->next field. Fix bug by initializing next field right after sched_group was allocated. Also-Reported-by: Jiang Liu <liuj97@gmail.com> Signed-off-by: Igor Mammedov <imammedo@redhat.com> Cc: a.p.zijlstra@chello.nl Cc: pjt@google.com Cc: seto.hidetoshi@jp.fujitsu.com Link: http://lkml.kernel.org/r/1336559908-32533-1-git-send-email-imammedo@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-04-29Merge tag 'pm-for-3.4-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fixes from Rafael J. Wysocki: "Fix for an issue causing hibernation to hang on systems with highmem (that practically means i386) due to broken memory management (bug introduced in 3.2, so -stable material) and PM documentation update making the freezer documentation follow the code again after some recent updates." * tag 'pm-for-3.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM / Freezer / Docs: Update documentation about freezing of tasks PM / Hibernate: fix the number of pages used for hibernate/thaw buffering
2012-04-27Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU fix from Ingo Molnar. * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rcu: Permit call_rcu() from CPU_DYING notifiers
2012-04-27Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar. * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Fix OOPS when build_sched_domains() percpu allocation fails sched: Fix more load-balancing fallout
2012-04-27Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar. * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Fix perf_event_for_each() to use sibling perf symbols: Read plt symbols from proper symtab_type binary tracing: Fix stacktrace of latency tracers (irqsoff and friends) perf tools: Add 'G' and 'H' modifiers to event parsing tracing: Fix regression with tracing_on perf tools: Drop CROSS_COMPILE from flex and bison calls perf report: Fix crash showing warning related to kernel maps tracing: Fix build breakage without CONFIG_PERF_EVENTS (again)
2012-04-27Merge branch 'for-v3.4-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux Pull build fixes for less mainstream architectures from Paul Gortmaker: "These are fixes for frv(1), blackfin(2), powerpc(1) and xtensa(4). Fortunately the touches are nearly all specific to files just used by the arch in question. The two touches to shared/common files [kernel/irq/debug.h and drivers/pci/Makefile] are trivial to assess as no risk to anyone. Half of them relate to xtensa directly. It was only when I fixed the last xtensa issue that I realized that the arch has been broken for a significant time, and isn't a specific v3.4 regression. So if you wanted, we could leave xtensa lying bleeding in the street for a couple more weeks and queue those for 3.5. But given they are no risk to anyone outside of xtensa, I figured to just leave them in. If you are OK with taking the xtensa fixes, then please pull to get: - one last implicit include uncovered by system.h that is in a file specific to just one powerpc defconfig. (I'd sync'd with BenH). - fix an oversight in the PCI makefile where shared code wasn't being compiled for ARCH=frv - fix a missing include for GPIO in blackfin framebuffer. - audit and tag endif in blackfin ezkit board file, in order to find and fix the misplaced endif masking a block of code. - fix irq/debug.h choice of temporary macro names to be more internal so they don't conflict with names used by xtensa. - fix a reference to an undeclared local var in xtensa's signal.c - fix an implicit bug.h usage in xtensa's asm/io.h uncovered by my removing bug.h from kernel.h - fix xtensa to properly indicate it is using asm-generic/hardirq.h in order to resolve the link error - undefined ack_bad_irq The xtensa still fails final link as my latest binutils does something evil when ld forward-relocates unlikely() blocks, but in theory people who have older/valid toolchains could now use the thing." * 'for-v3.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: xtensa: fix build fail on undefined ack_bad_irq blackfin: fix ifdef fustercluck in mach-bf538/boards/ezkit.c blackfin: fix compile error in bfin-lq035q1-fb.c pci: frv architecture needs generic setup-bus infrastructure irq: hide debug macros so they don't collide with others. xtensa: fix build error in xtensa/include/asm/io.h xtensa: fix build failure in xtensa/kernel/signal.c powerpc: fix system.h fallout in sysdev/scom.c [chroma_defconfig]
2012-04-26perf: Fix perf_event_for_each() to use siblingMichael Ellerman
In perf_event_for_each() we call a function on an event, and then iterate over the siblings of the event. However we don't call the function on the siblings, we call it repeatedly on the original event - it seems "obvious" that we should be calling it with sibling as the argument. It looks like this broke in commit 75f937f24bd9 ("Fix ctx->mutex vs counter->mutex inversion"). The only effect of the bug is that the PERF_IOC_FLAG_GROUP parameter to the ioctls doesn't work. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1334109253-31329-1-git-send-email-michael@ellerman.id.au Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-04-26sched: Fix OOPS when build_sched_domains() percpu allocation failshe, bo
Under extreme memory used up situations, percpu allocation might fail. We hit it when system goes to suspend-to-ram, causing a kworker panic: EIP: [<c124411a>] build_sched_domains+0x23a/0xad0 Kernel panic - not syncing: Fatal exception Pid: 3026, comm: kworker/u:3 3.0.8-137473-gf42fbef #1 Call Trace: [<c18cc4f2>] panic+0x66/0x16c [...] [<c1244c37>] partition_sched_domains+0x287/0x4b0 [<c12a77be>] cpuset_update_active_cpus+0x1fe/0x210 [<c123712d>] cpuset_cpu_inactive+0x1d/0x30 [...] With this fix applied build_sched_domains() will return -ENOMEM and the suspend attempt fails. Signed-off-by: he, bo <bo.he@intel.com> Reviewed-by: Zhang, Yanmin <yanmin.zhang@intel.com> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: <stable@kernel.org> Link: http://lkml.kernel.org/r/1335355161.5892.17.camel@hebo [ So, we fail to deallocate a CPU because we cannot allocate RAM :-/ I don't like that kind of sad behavior but nevertheless it should not crash under high memory load. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-04-26sched: Fix more load-balancing falloutPeter Zijlstra
Commits 367456c756a6 ("sched: Ditch per cgroup task lists for load-balancing") and 5d6523ebd ("sched: Fix load-balance wreckage") left some more wreckage. By setting loop_max unconditionally to ->nr_running load-balancing could take a lot of time on very long runqueues (hackbench!). So keep the sysctl as max limit of the amount of tasks we'll iterate. Furthermore, the min load filter for migration completely fails with cgroups since inequality in per-cpu state can easily lead to such small loads :/ Furthermore the change to add new tasks to the tail of the queue instead of the head seems to have some effect.. not quite sure I understand why. Combined these fixes solve the huge hackbench regression reported by Tim when hackbench is ran in a cgroup. Reported-by: Tim Chen <tim.c.chen@linux.intel.com> Acked-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1335365763.28150.267.camel@twins [ got rid of the CONFIG_PREEMPT tuning and made small readability edits ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-04-25Merge branch 'tip/perf/urgent-2' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/urgent
2012-04-25Merge branch 'rcu/urgent' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent
2012-04-24PM / Hibernate: fix the number of pages used for hibernate/thaw bufferingBojan Smojver
Hibernation regression fix, since 3.2. Calculate the number of required free pages based on non-high memory pages only, because that is where the buffers will come from. Commit 081a9d043c983f161b78fdc4671324d1342b86bc introduced a new buffer page allocation logic during hibernation, in order to improve the performance. The amount of pages allocated was calculated based on total amount of pages available, although only non-high memory pages are usable for this purpose. This caused hibernation code to attempt to over allocate pages on platforms that have high memory, which led to hangs. Signed-off-by: Bojan Smojver <bojan@rexursive.com> Signed-off-by: Rafael J. Wysocki <rjw@suse.de>
2012-04-23irq: hide debug macros so they don't collide with others.Paul Gortmaker
The file kernel/irq/debug.h temporarily defines P, PS, PD and then undefines them. However these names aren't really "internal" enough, and collide with other more legit users such as the ones in the xtensa arch, causing: In file included from kernel/irq/internals.h:58:0, from kernel/irq/irqdesc.c:18: kernel/irq/debug.h:8:0: warning: "PS" redefined [enabled by default] arch/xtensa/include/asm/regs.h:59:0: note: this is the location of the previous definition Add a handful of underscores to do a better job of hiding these temporary macros. Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-04-19tracing: Fix stacktrace of latency tracers (irqsoff and friends)Steven Rostedt
While debugging a latency with someone on IRC (mirage335) on #linux-rt (OFTC), we discovered that the stacktrace output of the latency tracers (preemptirqsoff) was empty. This bug was caused by the creation of the dynamic length stack trace again (like commit 12b5da3 "tracing: Fix ent_size in trace output" was). This bug is caused by the latency tracers requiring the next event to determine the time between the current event and the next. But by grabbing the next event, the iter->ent_size is set to the next event instead of the current one. As the stacktrace event is the last event, this makes the ent_size zero and causes nothing to be printed for the stack trace. The dynamic stacktrace uses the ent_size to determine how much of the stack can be printed. The ent_size of zero means no stack. The simple fix is to save the iter->ent_size before finding the next event. Note, mirage335 asked to remain anonymous from LKML and git, so I will not add the Reported-by and Tested-by tags, even though he did report the issue and tested the fix. Cc: stable@vger.kernel.org # 3.1+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-04-19tick: Fix the spurious broadcast timer ticks after resumeSuresh Siddha
During resume, tick_resume_broadcast() programs the broadcast timer in oneshot mode unconditionally. On the platforms where broadcast timer is not really required, this will generate spurious broadcast timer ticks upon resume. For example, on the always running apic timer platforms with HPET, I see spurious hpet tick once every ~5minutes (which is the 32-bit hpet counter wraparound time). Similar to boot time, during resume make the oneshot mode setting of the broadcast clock event device conditional on the state of active broadcast users. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: svenjoac@gmx.de Cc: torvalds@linux-foundation.org Cc: rjw@sisk.pl Link: http://lkml.kernel.org/r/1334802459.28674.209.camel@sbsiddha-desk.sc.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-04-19tick: Ensure that the broadcast device is initializedThomas Gleixner
Santosh found another trap when we avoid to initialize the broadcast device in the switch_to_oneshot code. The broadcast device might be still in SHUTDOWN state when we actually need to use it. That obviously breaks, as set_next_event() is called on a shutdown device. This did not break on x86, but Suresh analyzed it: From the review, most likely on Sven's system we are force enabling the hpet using the pci quirk's method very late. And in this case, hpet_clockevent (which will be global_clock_event) handler can be null, specifically as this platform might not be using deeper c-states and using the reliable APIC timer. Prior to commit 'fa4da365bc7772c', that handler will be set to 'tick_handle_oneshot_broadcast' when we switch the broadcast timer to oneshot mode, even though we don't use it. Post commit 'fa4da365bc7772c', we stopped switching the broadcast mode to oneshot as this is not really needed and his platform's global_clock_event's handler will remain null. While on my SNB laptop, same is set to 'clockevents_handle_noop' because hpet gets enabled very early. (noop handler on my platform set when the early enabled hpet timer gets replaced by the lapic timer). But the commit 'fa4da365bc7772c' tracked the broadcast timer mode in the SW as oneshot, even though it didn't touch the HW timer. During resume however, tick_resume_broadcast() saw the SW broadcast mode as oneshot and actually programmed the broadcast device also into oneshot mode. So this triggered the null pointer de-reference after the hpet wraps around and depending on what the hpet counter is set to. On the normal platforms where hpet gets enabled early we should be seeing a spurious interrupt (in my SNB laptop I see one spurious interrupt after around 5 minutes ;) which is 32-bit hpet counter wraparound time), but that's a separate issue. Enforce the mode setting when trying to set an event. Reported-and-tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: torvalds@linux-foundation.org Cc: svenjoac@gmx.de Cc: rjw@sisk.pl Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1204181723350.2542@ionos
2012-04-18tick: Fix oneshot broadcast setup reallyThomas Gleixner
Sven Joachim reported, that suspend/resume on rc3 trips over a NULL pointer dereference. Linus spotted the clockevent handler being NULL. commit fa4da365b(clockevents: tTack broadcast device mode change in tick_broadcast_switch_to_oneshot()) tried to fix a problem with the broadcast device setup, which was introduced in commit 77b0d60c5( clockevents: Leave the broadcast device in shutdown mode when not needed). The initial commit avoided to set up the broadcast device when no broadcast request bits were set, but that left the broadcast device disfunctional. In consequence deep idle states which need the broadcast device were not woken up. commit fa4da365b tried to fix that by initializing the state of the broadcast facility, but that missed the fact, that nothing initializes the event handler and some other state of the underlying clock event device. The fix is to revert both commits and make only the mode setting of the clock event device conditional on the state of active broadcast users. That initializes everything except the low level device mode, but this happens when the broadcast functionality is invoked by deep idle. Reported-and-tested-by: Sven Joachim <svenjoac@gmx.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1204181205540.2542@ionos
2012-04-17rcu: Permit call_rcu() from CPU_DYING notifiersPaul E. McKenney
As of: 29494be71afe ("rcu,cleanup: simplify the code when cpu is dying") RCU adopts callbacks from the dying CPU in its CPU_DYING notifier, which means that any callbacks posted by later CPU_DYING notifiers are ignored until the CPU comes back online. A WARN_ON_ONCE() was added to __call_rcu() by: e56014000816 ("rcu: Simplify offline processing") to check for this condition. Although this condition did not trigger (at least as far as I know) during -next testing, it did recently trigger in mainline: https://lkml.org/lkml/2012/4/2/34 What is needed longer term is for RCU's CPU_DEAD notifier to adopt any callbacks that were posted by CPU_DYING notifiers, however, the Linux kernel has been running with this sort of thing happening for quite some time. So the only thing that qualifies as a regression is the WARN_ON_ONCE(), which this commit removes. Making RCU's CPU_DEAD notifier adopt callbacks posted by CPU_DYING notifiers is a topic for the 3.5 release of the Linux kernel. Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-04-16tracing: Fix regression with tracing_onSteven Rostedt
The change to make tracing_on affect only the ftrace ring buffer, caused a bug where it wont affect any ring buffer. The problem was that the buffer of the trace_array was passed to the write function and not the trace array itself. The trace_array can change the buffer when running a latency tracer. If this happens, then the buffer being disabled may not be the buffer currently used by ftrace. This will cause the tracing_on file to become useless. The simple fix is to pass the trace_array to the write function instead of the buffer. Then the actual buffer may be changed. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-04-13Merge branch 'systemh-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux Pull system.h fixups for less common arch's from Paul Gortmaker: "Here is what is hopefully the last of the system.h related fixups. The fixes for Alpha and ia64 are code relocations consistent with what was done for the more mainstream architectures. Note that the diffstat lines removed vs lines added are not the same since I've fixed some of the whitespace issues in the relocated code blocks. However they are functionally the same. Compile tested locally, plus these two have been in linux-next for a while. There is also a trivial one line system.h related fix for the Tilera arch from Chris Metcalf to fix an implict include.." * 'systemh-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: irq_work: fix compile failure on tile from missing include ia64: populate the cmpxchg header with appropriate code alpha: fix build failures from system.h dismemberment
2012-04-13tracing: Fix build breakage without CONFIG_PERF_EVENTS (again)Mark Brown
Today's -next fails to link for me: kernel/built-in.o:(.data+0x178e50): undefined reference to `perf_ftrace_event_register' It looks like multiple fixes have been merged for the issue fixed by commit fa73dc9 (tracing: Fix build breakage without CONFIG_PERF_EVENTS) though I can't identify the other changes that have gone in at the minute, it's possible that the changes which caused the breakage fixed by the previous commit got dropped but the fix made it in. Link: http://lkml.kernel.org/r/1334307179-21255-1-git-send-email-broonie@opensource.wolfsonmicro.com Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-04-13irq_work: fix compile failure on tile from missing includeChris Metcalf
Building with IRQ_WORK configured results in kernel/irq_work.c: In function ‘irq_work_run’: kernel/irq_work.c:110: error: implicit declaration of function ‘irqs_disabled’ The appropriate header just needs to be included. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-04-12Merge tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6Linus Torvalds
Pull a fix for the recent irqdomain bug fixes from Grant Likely: "I flubbed one patch in the last pull request which broke a format string on 64 bit platforms. Here's the fix." * tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6: irq_domain: fix type mismatch in debugfs output format
2012-04-12irq_domain: fix type mismatch in debugfs output formatGrant Likely
sizeof(void*) returns an unsigned long, but it was being used as a width parameter to a "%-*s" format string which requires an int. On 64 bit platforms this causes a type mismatch: linux/kernel/irq/irqdomain.c:575: warning: field width should have type 'int', but argument 6 has type 'long unsigned int' This change casts the size to an int so printf gets the right data type. Reported-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: David Daney <david.daney@cavium.com>
2012-04-12Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "The itimer removal one is not strictly a fix, but I really wanted to avoid a rebase of the urgent ones." * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Revert "clocksource: Load the ACPI PM clocksource asynchronously" clockevents: tTack broadcast device mode change in tick_broadcast_switch_to_oneshot() itimer: Use printk_once instead of WARN_ONCE nohz: Fix stale jiffies update in tick_nohz_restart() tick: Document TICK_ONESHOT config option proc: stats: Use arch_idle_time for idle and iowait times if available itimer: Schedule silent NULL pointer fixup in setitimer() for removal
2012-04-12Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds
Merge fixes from Andrew Morton. * emailed from Andrew Morton <akpm@linux-foundation.org>: (14 patches) panic: fix stack dump print on direct call to panic() drivers/rtc/rtc-pl031.c: enable clock on all ST variants Revert "mm: vmscan: fix misused nr_reclaimed in shrink_mem_cgroup_zone()" hugetlb: fix race condition in hugetlb_fault() drivers/rtc/rtc-twl.c: use static register while reading time drivers/rtc/rtc-s3c.c: add placeholder for driver private data drivers/rtc/rtc-s3c.c: fix compilation error MAINTAINERS: add PCDP console maintainer memcg: do not open code accesses to res_counter members drivers/rtc/rtc-efi.c: fix section mismatch warning drivers/rtc/rtc-r9701.c: reset registers if invalid values are detected drivers/char/random.c: fix boot id uniqueness race memcg: fix broken boolen expression memcg: fix up documentation on global LRU
2012-04-12panic: fix stack dump print on direct call to panic()Jason Wessel
Commit 6e6f0a1f0fa6 ("panic: don't print redundant backtraces on oops") causes a regression where no stack trace will be printed at all for the case where kernel code calls panic() directly while not processing an oops, and of course there are 100's of instances of this type of call. The original commit executed the check (!oops_in_progress), but this will always be false because just before the dump_stack() there is a call to bust_spinlocks(1), which does the following: void __attribute__((weak)) bust_spinlocks(int yes) { if (yes) { ++oops_in_progress; The proper way to resolve the problem that original commit tried to solve is to avoid printing a stack dump from panic() when the either of the following conditions is true: 1) TAINT_DIE has been set (this is done by oops_end()) This indicates and oops has already been printed. 2) oops_in_progress > 1 This guards against the rare case where panic() is invoked a second time, or in between oops_begin() and oops_end() Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: <stable@vger.kernel.org> [3.3+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12Merge tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6Linus Torvalds
Pull irqdomain bug fixes from Grant Likely: "This branch fixes a bug in irq_create_mapping() where an error return from irq_alloc_desc_from() gets ignored. It also removes irq_virq_count to fix a bug on powerpc where the irqdomain code does not find irqs allocated above the CONFIG_NR_IRQS boundary. The remaining patches get rid of an completely pointless export and fix some minor bugs in the irqdomain debug output." * tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6: irq_domain: Move irq_virq_count into NOMAP revmap irqdomain: Fix debugfs formatting irq_domain: correct the debugfs file name irq: Kill pointless irqd_to_hw export irq/irq_domain: Quit ignoring error returns from irq_alloc_desc_from().
2012-04-12irq_domain: Move irq_virq_count into NOMAP revmapGrant Likely
This patch replaces the old global setting of irq_virq_count that is only used by the NOMAP mapping and instead uses a revmap_data property so that the maximum NOMAP allocation can be set per NOMAP irq_domain. There is exactly one user of irq_virq_count in-tree right now: PS3. Also, irq_virq_count is only useful for the NOMAP mapping. So, instead of having a single global irq_virq_count values, this change drops it entirely and added a max_irq argument to irq_domain_add_nomap(). That makes it a property of an individual nomap irq domain instead of a global system settting. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com>
2012-04-11cred: copy_process() should clear child->replacement_session_keyringOleg Nesterov
keyctl_session_to_parent(task) sets ->replacement_session_keyring, it should be processed and cleared by key_replace_session_keyring(). However, this task can fork before it notices TIF_NOTIFY_RESUME and the new child gets the bogus ->replacement_session_keyring copied by dup_task_struct(). This is obviously wrong and, if nothing else, this leads to put_cred(already_freed_cred). change copy_creds() to clear this member. If copy_process() fails before this point the wrong ->replacement_session_keyring doesn't matter, exit_creds() won't be called. Cc: <stable@vger.kernel.org> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-11irqdomain: Fix debugfs formattingGrant Likely
This patch fixes the irq_domain_mapping debugfs output to pad pointer values with leading zeros so that pointer values are displayed correctly. Otherwise you get output similar to "0x 5e0000000000000". Also, when the irq_domain is set to 'null' Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: David Daney <david.daney@cavium.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
2012-04-10irq_domain: correct the debugfs file nameMika Westerberg
The actual name of the irq_domain mapping debugfs file is "irq_domain_mapping" not "virq_mapping". Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-04-10irq/irq_domain: Quit ignoring error returns from irq_alloc_desc_from().David Daney
In commit 4bbdd45a (irq_domain/powerpc: eliminate irq_map; use irq_alloc_desc() instead) code was added that ignores error returns from irq_alloc_desc_from() by (silently) casting the return value to unsigned. The negitive value error return now suddenly looks like a valid irq number. Commits cc79ca69 (irq_domain: Move irq_domain code from powerpc to kernel/irq) and 1bc04f2c (irq_domain: Add support for base irq and hwirq in legacy mappings) move this code to its current location in irqdomain.c The result of all of this is a null pointer dereference OOPS if one of the error cases is hit. The fix: Don't cast away the negativeness of the return value and then check for errors. Signed-off-by: David Daney <david.daney@cavium.com> Acked-by: Rob Herring <rob.herring@calxeda.com> [grant.likely: dropped addition of new 'irq' variable] Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-04-10clockevents: tTack broadcast device mode change in ↵Suresh Siddha
tick_broadcast_switch_to_oneshot() In the commit 77b0d60c5adf39c74039e2142a1d3cd1e4d53799, "clockevents: Leave the broadcast device in shutdown mode when not needed", we were bailing out too quickly in tick_broadcast_switch_to_oneshot(), with out tracking the broadcast device mode change to 'TICKDEV_MODE_ONESHOT'. This breaks the platforms which need broadcast device oneshot services during deep idle states. tick_broadcast_oneshot_control() thinks that it is in periodic mode and fails to take proper decisions based on the CLOCK_EVT_NOTIFY_BROADCAST_[ENTER, EXIT] notifications during deep idle entry/exit. Fix this by tracking the broadcast device mode as 'TICKDEV_MODE_ONESHOT', before leaving the broadcast HW device in shutdown mode if there are no active requests for the moment. Reported-and-tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: johnstul@us.ibm.com Link: http://lkml.kernel.org/r/1334011304.12400.81.camel@sbsiddha-desk.sc.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-04-10itimer: Use printk_once instead of WARN_ONCEThomas Gleixner
David pointed out, that WARN_ONCE() to report usage of an deprecated misfeature make folks unhappy. Use printk_once() instead. Andrew told me to stop grumbling and to remove the silly typecast while touching the file. Reported-by: David Rientjes <rientjes@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-04-07Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security layer fixlet from James Morris. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: sysctl: fix write access to dmesg_restrict/kptr_restrict
2012-04-06nohz: Fix stale jiffies update in tick_nohz_restart()Neal Cardwell
Fix tick_nohz_restart() to not use a stale ktime_t "now" value when calling tick_do_update_jiffies64(now). If we reach this point in the loop it means that we crossed a tick boundary since we grabbed the "now" timestamp, so at this point "now" refers to a time in the old jiffy, so using the old value for "now" is incorrect, and is likely to give us a stale jiffies value. In particular, the first time through the loop the tick_do_update_jiffies64(now) call is always a no-op, since the caller, tick_nohz_restart_sched_tick(), will have already called tick_do_update_jiffies64(now) with that "now" value. Note that tick_nohz_stop_sched_tick() already uses the correct approach: when we notice we cross a jiffy boundary, grab a new timestamp with ktime_get(), and *then* update jiffies. Signed-off-by: Neal Cardwell <ncardwell@google.com> Cc: Ben Segall <bsegall@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1332875377-23014-1-git-send-email-ncardwell@google.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>