Peter Zijlstra fa73158710 perf: Fix capabilities bitfield compatibility in 'struct perf_event_mmap_page' ... Solve the problems around the broken definition of perf_event_mmap_page:: cap_usr_time and cap_usr_rdpmc fields which used to overlap, partially fixed by: 860f085b74 ("perf: Fix broken union in 'struct perf_event_mmap_page'") The problem with the fix (merged in v3.12-rc1 and not yet released officially), noticed by Vince Weaver is that the new behavior is not detectable by new user-space, and that due to the reuse of the field names it's easy to mis-compile a binary if old headers are used on a new kernel or new headers are used on an old kernel. To solve all that make this change explicit, detectable and self-contained, by iterating the ABI the following way: - Always clear bit 0, and rename it to usrpage->cap_bit0, to at least not confuse old user-space binaries. RDPMC will be marked as unavailable to old binaries but that's within the ABI, this is a capability bit. - Rename bit 1 to ->cap_bit0_is_deprecated and always set it to 1, so new libraries can reliably detect that bit 0 is deprecated and perma-zero without having to check the kernel version. - Use bits 2, 3, 4 for the newly defined, correct functionality: cap_user_rdpmc : 1, /* The RDPMC instruction can be used to read counts */ cap_user_time : 1, /* The time_* fields are used */ cap_user_time_zero : 1, /* The time_zero field is used */ - Rename all the bitfield names in perf_event.h to be different from the old names, to make sure it's not possible to mis-compile it accidentally with old assumptions. The 'size' field can then be used in the future to add new fields and it will act as a natural ABI version indicator as well. Also adjust tools/perf/ userspace for the new definitions, noticed by Adrian Hunter. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Also-Fixed-by: Adrian Hunter <adrian.hunter@intel.com> Link: http://lkml.kernel.org/n/tip-zr03yxjrpXesOzzupszqglbv@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>		2013-09-20 09:45:11 +02:00
..
cpu	idle: Enable interrupts in the weak arch_cpu_idle() implementation	2013-06-14 23:01:05 +02:00
debug
events	perf: Fix capabilities bitfield compatibility in 'struct perf_event_mmap_page'	2013-09-20 09:45:11 +02:00
gcov	kernel: replace strict_strto*() with kstrto*()	2013-09-12 15:38:03 -07:00
irq	Remove GENERIC_HARDIRQ config option	2013-09-13 15:09:52 +02:00
power	ACPI and power management fixes for 3.12-rc1	2013-09-12 11:22:45 -07:00
printk	TTY/Serial driver patches for 3.12-rc1	2013-09-03 11:38:36 -07:00
sched	Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2013-09-12 10:44:13 -07:00
time	Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2013-09-04 09:36:54 -07:00
trace	Not much changes for the 3.12 merge window. The major tracing changes	2013-09-09 14:42:15 -07:00
.gitignore
acct.c
async.c
audit_tree.c
audit_watch.c
audit.c
audit.h	audit: fix mq_open and mq_unlink to add the MQ root as a hidden parent audit_names record	2013-07-09 10:33:19 -07:00
auditfilter.c	audit: Fix decimal constant description	2013-07-09 10:33:19 -07:00
auditsc.c	audit: fix mq_open and mq_unlink to add the MQ root as a hidden parent audit_names record	2013-07-09 10:33:19 -07:00
backtracetest.c
bounds.c
capability.c	xfs: update for v3.12-rc1	2013-09-09 11:19:09 -07:00
cgroup_freezer.c	cgroup: make css_for_each_descendant() and friends include the origin css in the iteration	2013-08-08 20:11:27 -04:00
cgroup.c	Kill indirect include of file.h from eventfd.h, use fdget() in cgroup.c	2013-09-07 19:54:57 -04:00
compat.c
configs.c
context_tracking.c	context_tracking: User/kernel broundary cross trace events	2013-08-14 17:14:48 +02:00
cpu_pm.c
cpu.c	ACPI / processor: Acquire writer lock to update CPU maps	2013-08-13 12:20:16 +02:00
cpuset.c	Merge branch 'for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2013-09-03 18:25:03 -07:00
crash_dump.c
cred.c
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c	ptrace: revert "Prepare to fix racy accesses on task breakpoints"	2013-07-09 10:33:26 -07:00
extable.c	extable: skip sorting if the table is empty	2013-09-11 15:58:25 -07:00
fork.c	Merge git://git.kvack.org/~bcrl/aio-next	2013-09-13 10:55:58 -07:00
freezer.c	freezer: set PF_SUSPEND_TASK flag on tasks that call freeze_processes	2013-07-30 14:05:06 +02:00
futex_compat.c
futex.c	futex: Use freezable blocking call	2013-06-25 23:11:19 +02:00
groups.c	userns: Kill nsown_capable it makes the wrong thing easy	2013-08-30 23:44:11 -07:00
hrtimer.c	kernel: delete __cpuinit usage from all core kernel files	2013-07-14 19:36:59 -04:00
hung_task.c	hung_task debugging: Print more info when reporting the problem	2013-08-02 11:02:42 +02:00
irq_work.c
itimer.c
jump_label.c	jump_label: Split jumplabel ratelimit	2013-08-09 07:53:54 -07:00
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c	kexec: remove unnecessary return	2013-09-11 15:59:10 -07:00
kmod.c	usermodehelper: kill the sub_info->path[0] check	2013-07-03 16:08:02 -07:00
kprobes.c	kprobes: allow to specify custom allocator for insn caches	2013-09-11 15:58:52 -07:00
ksysfs.c	kernel: replace strict_strto*() with kstrto*()	2013-09-12 15:38:03 -07:00
kthread.c
latencytop.c
lglock.c	lglock: Update lockdep annotations to report recursive local locks	2013-07-12 13:51:19 +02:00
lockdep_internals.h
lockdep_proc.c
lockdep_states.h
lockdep.c
Makefile	Remove GENERIC_HARDIRQ config option	2013-09-13 15:09:52 +02:00
modsign_certificate.S
modsign_pubkey.c	kernel/modsign_pubkey.c: fix init const for module signing code	2013-09-11 15:58:21 -07:00
module_signing.c
module-internal.h
module.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2013-09-05 08:50:26 -07:00
mutex-debug.c
mutex-debug.h
mutex.c	Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2013-09-04 08:18:19 -07:00
mutex.h
notifier.c
nsproxy.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2013-09-07 14:35:32 -07:00
padata.c	padata - Register hotcpu notifier after initialization	2013-08-29 14:37:59 +10:00
panic.c	panic: call panic handlers before kmsg_dump	2013-09-11 15:59:30 -07:00
params.c	kernel: replace strict_strto*() with kstrto*()	2013-09-12 15:38:03 -07:00
pid_namespace.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2013-09-07 14:35:32 -07:00
pid.c	pidns: Fix hang in zap_pid_ns_processes by sending a potentially extra wakeup	2013-08-30 17:30:37 -07:00
posix-cpu-timers.c	posix_timers: fix racy timer delta caching on task exit	2013-07-03 16:54:42 +02:00
posix-timers.c
profile.c	kernel: delete __cpuinit usage from all core kernel files	2013-07-14 19:36:59 -04:00
ptrace.c	__ptrace_may_access() should not deny sub-threads	2013-09-11 15:59:01 -07:00
range.c	range: Do not add new blank slot with add_range_with_merge	2013-06-18 11:32:10 -05:00
rcu.h	rcu: Make call_rcu() leak callbacks for debug-object errors	2013-08-18 17:40:03 -07:00
rcupdate.c	Not much changes for the 3.12 merge window. The major tracing changes	2013-09-09 14:42:15 -07:00
rcutiny_plugin.h	rcu: Add const annotation to char * for RCU tracepoints and functions	2013-07-29 17:07:49 -04:00
rcutiny.c	rcu: Add const annotation to char * for RCU tracepoints and functions	2013-07-29 17:07:49 -04:00
rcutorture.c	rcu: Make rcutorture emit online failures if verbose	2013-08-20 11:38:45 -07:00
rcutree_plugin.h	nohz_full: Force RCU's grace-period kthreads onto timekeeping CPU	2013-08-31 14:44:02 -07:00
rcutree_trace.c
rcutree.c	Merge branches 'doc.2013.08.19a', 'fixes.2013.08.20a', 'sysidle.2013.08.31a' and 'torture.2013.08.20a' into HEAD	2013-08-31 14:44:45 -07:00
rcutree.h	nohz_full: Force RCU's grace-period kthreads onto timekeeping CPU	2013-08-31 14:44:02 -07:00
reboot.c	reboot: move arch/x86 reboot= handling to generic kernel	2013-07-09 10:33:29 -07:00
relay.c	kernel: delete __cpuinit usage from all core kernel files	2013-07-14 19:36:59 -04:00
res_counter.c	memcg: reduce function dereference	2013-09-12 15:38:02 -07:00
resource.c	kernel/resource.c: remove the unneeded assignment in function __find_resource	2013-07-03 16:08:06 -07:00
rtmutex_common.h
rtmutex-debug.c
rtmutex-debug.h
rtmutex-tester.c
rtmutex.c
rtmutex.h
rwsem.c
seccomp.c
semaphore.c
signal.c	kernel-wide: fix missing validations on __get/__put/__copy_to/__copy_from_user()	2013-09-11 15:58:18 -07:00
smp.c	kernel/smp.c: quit unconditionally enabling irqs in on_each_cpu_mask().	2013-09-11 15:58:25 -07:00
smpboot.c	kernel: delete __cpuinit usage from all core kernel files	2013-07-14 19:36:59 -04:00
smpboot.h
softirq.c	Remove GENERIC_HARDIRQ config option	2013-09-13 15:09:52 +02:00
spinlock.c	kernel/spinlock.c: add default arch_*_relax definitions for GENERIC_LOCKBREAK	2013-09-11 15:58:21 -07:00
srcu.c
stacktrace.c
stop_machine.c
sys_ni.c
sys.c	userns: Kill nsown_capable it makes the wrong thing easy	2013-08-30 23:44:11 -07:00
sysctl_binary.c	kernel: remove unnecessary head file	2013-06-26 18:01:46 +09:00
sysctl.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2013-09-12 15:01:38 -07:00
task_work.c	task_work: documentation	2013-09-11 15:58:27 -07:00
taskstats.c
test_kprobes.c
time.c	sched: Rename sched.c as sched/core.c in comments and Documentation	2013-06-19 12:58:42 +02:00
timeconst.bc
timer.c	kernel: delete __cpuinit usage from all core kernel files	2013-07-14 19:36:59 -04:00
tracepoint.c
tsacct.c
uid16.c	userns: Kill nsown_capable it makes the wrong thing easy	2013-08-30 23:44:11 -07:00
up.c	smp.h: move !SMP version of on_each_cpu() out-of-line	2013-09-11 15:58:25 -07:00
user_namespace.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2013-09-07 14:35:32 -07:00
user-return-notifier.c
user.c	userns: Better restrictions on when proc and sysfs can be mounted	2013-08-26 19:17:03 -07:00
utsname_sysctl.c
utsname.c	userns: Kill nsown_capable it makes the wrong thing easy	2013-08-30 23:44:11 -07:00
wait.c	kernel: fix new kernel-doc warning in wait.c	2013-08-19 09:08:54 -07:00
watchdog.c	watchdog: Make it work under full dynticks	2013-07-30 22:29:15 +02:00
workqueue_internal.h	sched: Rename sched.c as sched/core.c in comments and Documentation	2013-06-19 12:58:42 +02:00
workqueue.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2013-09-06 09:36:28 -07:00