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Linus Torvalds f122a08b19 capability: just use a 'u64' instead of a 'u32[2]' array 
Back in 2008 we extended the capability bits from 32 to 64, and we did
it by extending the single 32-bit capability word from one word to an
array of two words.  It was then obfuscated by hiding the "2" behind two
macro expansions, with the reasoning being that maybe it gets extended
further some day.

That reasoning may have been valid at the time, but the last thing we
want to do is to extend the capability set any more.  And the array of
values not only causes source code oddities (with loops to deal with
it), but also results in worse code generation.  It's a lose-lose
situation.

So just change the 'u32[2]' into a 'u64' and be done with it.

We still have to deal with the fact that the user space interface is
designed around an array of these 32-bit values, but that was the case
before too, since the array layouts were different (ie user space
doesn't use an array of 32-bit values for individual capability masks,
but an array of 32-bit slices of multiple masks).

So that marshalling of data is actually simplified too, even if it does
remain somewhat obscure and odd.

This was all triggered by my reaction to the new "cap_isidentical()"
introduced recently.  By just using a saner data structure, it went from

	unsigned __capi;
	CAP_FOR_EACH_U32(__capi) {
		if (a.cap[__capi] != b.cap[__capi])
			return false;
	}
	return true;

to just being

	return a.val == b.val;

instead.  Which is rather more obvious both to humans and to compilers.

Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Paul Moore <paul@paul-moore.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-03-01 10:01:22 -08:00
..
bpf - Daniel Verkamp has contributed a memfd series ("mm/memfd: add 2023-02-23 17:09:35 -08:00
cgroup Networking changes for 6.3. 2023-02-21 18:24:12 -08:00
configs mm, slob: rename CONFIG_SLOB to CONFIG_SLOB_DEPRECATED 2022-12-01 00:09:20 +01:00
debug kdb: use srcu console list iterator 2022-12-02 11:25:00 +01:00
dma swiotlb: mark swiotlb_memblock_alloc() as __init 2023-02-22 06:44:48 -08:00
entry entry: kmsan: introduce kmsan_unpoison_entry_regs() 2022-10-03 14:03:25 -07:00
events Char/Misc and other driver subsystem changes for 6.3-rc1 2023-02-24 12:47:33 -08:00
futex - Prevent the leaking of a debug timer in futex_waitv() 2023-01-01 11:15:05 -08:00
gcov gcov: add support for checksum field 2022-12-21 14:31:52 -08:00
irq iommufd for 6.3 2023-02-24 14:34:12 -08:00
kcsan kcsan: test: don't put the expect array on the stack 2023-01-02 08:59:33 -08:00
livepatch Livepatching changes for 6.3 2023-02-23 14:00:10 -08:00
locking RCU pull request for v6.3 2023-02-21 10:45:51 -08:00
module modules-6.3-rc1 2023-02-23 14:05:08 -08:00
power Merge branches 'powercap', 'pm-domains', 'pm-em' and 'pm-opp' 2023-02-15 20:06:26 +01:00
printk printk changes for 6.3 2023-02-23 13:49:45 -08:00
rcu Merge branch 'stall.2023.01.09a' into HEAD 2023-02-02 16:40:07 -08:00
sched - Daniel Verkamp has contributed a memfd series ("mm/memfd: add 2023-02-23 17:09:35 -08:00
time Updates for timekeeping, timers and clockevent/source drivers: 2023-02-21 09:45:13 -08:00
trace probes cleanup updates for v6.3: 2023-02-25 13:06:28 -08:00
.gitignore
acct.c acct: fix potential integer overflow in encode_comp_t() 2022-11-30 16:13:18 -08:00
async.c
audit.c audit: use time_after to compare time 2022-08-29 19:47:03 -04:00
audit.h audit: remove selinux_audit_rule_update() declaration 2022-09-07 11:30:15 -04:00
audit_fsnotify.c audit: fix potential double free on error path from fsnotify_add_inode_mark 2022-08-22 18:50:06 -04:00
audit_tree.c
audit_watch.c audit_init_parent(): constify path 2022-09-01 17:39:30 -04:00
auditfilter.c
auditsc.c capability: just use a 'u64' instead of a 'u32[2]' array 2023-03-01 10:01:22 -08:00
backtracetest.c
bounds.c mm: multi-gen LRU: minimal implementation 2022-09-26 19:46:09 -07:00
capability.c capability: just use a 'u64' instead of a 'u32[2]' array 2023-03-01 10:01:22 -08:00
cfi.c cfi: Switch to -fsanitize=kcfi 2022-09-26 10:13:13 -07:00
compat.c
configs.c
context_tracking.c context_tracking: Fix noinstr vs KASAN 2023-01-13 11:48:18 +01:00
cpu.c cpu/hotplug: Do not bail-out in DYING/STARTING sections 2022-12-02 12:43:02 +01:00
cpu_pm.c cpuidle, cpu_pm: Remove RCU fiddling from cpu_pm_{enter,exit}() 2023-01-13 11:48:15 +01:00
crash_core.c mm: remove 'First tail page' members from struct page 2023-02-02 22:32:59 -08:00
crash_dump.c
cred.c cred: Do not default to init_cred in prepare_kernel_cred() 2022-11-01 10:04:52 -07:00
delayacct.c delayacct: support re-entrance detection of thrashing accounting 2022-09-26 19:46:07 -07:00
dma.c
exec_domain.c
exit.c arm64 updates for 6.3: 2023-02-21 15:27:48 -08:00
extable.c context_tracking: Take NMI eqs entrypoints over RCU 2022-07-05 13:32:59 -07:00
fail_function.c kernel/fail_function: fix memory leak with using debugfs_lookup() 2023-02-08 13:36:22 +01:00
fork.c - Daniel Verkamp has contributed a memfd series ("mm/memfd: add 2023-02-23 17:09:35 -08:00
freezer.c freezer,sched: Rewrite core freezer logic 2022-09-07 21:53:50 +02:00
gen_kheaders.sh kheaders: use standard naming for the temporary directory 2023-01-22 23:43:34 +09:00
groups.c security: Add LSM hook to setgroups() syscall 2022-07-15 18:21:49 +00:00
hung_task.c hung_task: print message when hung_task_warnings gets down to zero. 2023-02-09 17:03:20 -08:00
iomem.c
irq_work.c
jump_label.c jump_label: Prevent key->enabled int overflow 2022-12-01 15:53:05 -08:00
kallsyms.c kallsyms: Add self-test facility 2022-11-15 00:42:02 -08:00
kallsyms_internal.h kallsyms: Reduce the memory occupied by kallsyms_seqs_of_names[] 2022-11-12 18:47:36 -08:00
kallsyms_selftest.c kallsyms: Fix scheduling with interrupts disabled in self-test 2023-01-13 15:09:08 -08:00
kallsyms_selftest.h kallsyms: Add self-test facility 2022-11-15 00:42:02 -08:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c mm: replace vma->vm_flags direct modifications with modifier calls 2023-02-09 16:51:39 -08:00
kexec.c kexec: introduce sysctl parameters kexec_load_limit_* 2023-02-02 22:50:05 -08:00
kexec_core.c There is no particular theme here - mainly quick hits all over the tree. 2023-02-23 17:55:40 -08:00
kexec_elf.c
kexec_file.c kexec: introduce sysctl parameters kexec_load_limit_* 2023-02-02 22:50:05 -08:00
kexec_internal.h panic, kexec: make __crash_kexec() NMI safe 2022-09-11 21:55:06 -07:00
kheaders.c
kmod.c
kprobes.c x86/kprobes: Fix arch_check_optimized_kprobe check within optimized_kprobe range 2023-02-21 08:49:16 +09:00
ksysfs.c kernels/ksysfs.c: export kernel address bits 2023-01-20 14:30:45 +01:00
kthread.c kthread_worker: check all delayed works when destroy kthread worker 2023-02-02 22:50:02 -08:00
latencytop.c latencytop: use the last element of latency_record of system 2022-09-11 21:55:12 -07:00
Makefile kernel hardening fixes for v6.2-rc1 2022-12-23 12:00:24 -08:00
module_signature.c
notifier.c kernel/notifier: Remove CONFIG_SRCU 2023-02-02 16:26:06 -08:00
nsproxy.c fs/exec: switch timens when a task gets a new mm 2022-10-25 15:15:52 -07:00
padata.c Kbuild updates for v6.2 2022-12-19 12:33:32 -06:00
panic.c cpuidle: lib/bug: Disable rcu_is_watching() during WARN/BUG 2023-01-31 15:01:45 +01:00
params.c kernel/params.c: Use kstrtobool() instead of strtobool() 2023-01-25 14:07:21 -08:00
pid.c gfs2: Add glockfd debugfs file 2022-06-29 13:07:16 +02:00
pid_namespace.c - Daniel Verkamp has contributed a memfd series ("mm/memfd: add 2023-02-23 17:09:35 -08:00
pid_sysctl.h mm/memfd: add MFD_NOEXEC_SEAL and MFD_EXEC 2023-01-18 17:12:37 -08:00
profile.c kernel/profile.c: simplify duplicated code in profile_setup() 2022-09-11 21:55:12 -07:00
ptrace.c rseq: Introduce extensible rseq ABI 2022-12-27 12:52:10 +01:00
range.c
reboot.c kernel/reboot: Add SYS_OFF_MODE_RESTART_PREPARE mode 2022-10-04 15:59:36 +02:00
regset.c
relay.c mm: replace vma->vm_flags direct modifications with modifier calls 2023-02-09 16:51:39 -08:00
resource.c dax/kmem: Fix leak of memory-hotplug resources 2023-02-17 14:58:01 -08:00
resource_kunit.c
rseq.c rseq: Extend struct rseq with per-memory-map concurrency ID 2022-12-27 12:52:12 +01:00
scftorture.c
scs.c scs: add support for dynamic shadow call stacks 2022-11-09 18:06:35 +00:00
seccomp.c seccomp: fix kernel-doc function name warning 2023-01-13 17:01:06 -08:00
signal.c sched: Introduce per-memory-map concurrency ID 2022-12-27 12:52:11 +01:00
smp.c bitmap patches for v6.1-rc1 2022-10-10 12:49:34 -07:00
smpboot.c smpboot: use atomic_try_cmpxchg in cpu_wait_death and cpu_report_death 2022-09-11 21:55:10 -07:00
smpboot.h
softirq.c context_tracking: Take IRQ eqs entrypoints over RCU 2022-07-05 13:32:59 -07:00
stackleak.c
stacktrace.c
static_call.c
static_call_inline.c static_call: Add call depth tracking support 2022-10-17 16:41:16 +02:00
stop_machine.c Scheduler changes in this cycle were: 2022-05-24 11:11:13 -07:00
sys.c - Daniel Verkamp has contributed a memfd series ("mm/memfd: add 2023-02-23 17:09:35 -08:00
sys_ni.c kernel/sys_ni: add compat entry for fadvise64_64 2022-08-20 15:17:45 -07:00
sysctl-test.c kernel/sysctl-test: use SYSCTL_{ZERO/ONE_HUNDRED} instead of i_{zero/one_hundred} 2022-09-08 16:56:45 -07:00
sysctl.c sysctl: fix proc_dobool() usability 2023-02-21 13:34:07 -08:00
task_work.c task_work: use try_cmpxchg in task_work_add, task_work_cancel_match and task_work_run 2022-09-11 21:55:10 -07:00
taskstats.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
torture.c torture: Fix hang during kthread shutdown phase 2023-01-05 12:10:35 -08:00
tracepoint.c tracepoint: Allow livepatch module add trace event 2023-02-18 14:34:36 -05:00
tsacct.c
ucount.c
uid16.c
uid16.h
umh.c capability: just use a 'u64' instead of a 'u32[2]' array 2023-03-01 10:01:22 -08:00
up.c
user-return-notifier.c
user.c kernel/user: Allow user_struct::locked_vm to be usable for iommufd 2022-11-30 20:16:49 -04:00
user_namespace.c userns: fix a struct's kernel-doc notation 2023-02-02 22:50:04 -08:00
usermode_driver.c
utsname.c
utsname_sysctl.c kernel/utsname_sysctl.c: Fix hostname polling 2022-10-23 12:01:01 -07:00
watch_queue.c This was a moderately busy cycle for documentation, but nothing all that 2022-08-02 19:24:24 -07:00
watchdog.c powerpc updates for 6.0 2022-08-06 16:38:17 -07:00
watchdog_hld.c Revert "printk: add functions to prefer direct printing" 2022-06-23 18:41:40 +02:00
workqueue.c workqueue: Fold rebind_worker() within rebind_workers() 2023-01-13 07:50:40 -10:00
workqueue_internal.h