android_kernel_oneplus_msm8998/kernel
Josh Poimboeuf 31a2c5f7a2 cpu/speculation: Add 'mitigations=' cmdline option
commit 98af8452945c55652de68536afdde3b520fec429 upstream.

Keeping track of the number of mitigations for all the CPU speculation
bugs has become overwhelming for many users.  It's getting more and more
complicated to decide which mitigations are needed for a given
architecture.  Complicating matters is the fact that each arch tends to
have its own custom way to mitigate the same vulnerability.

Most users fall into a few basic categories:

a) they want all mitigations off;

b) they want all reasonable mitigations on, with SMT enabled even if
   it's vulnerable; or

c) they want all reasonable mitigations on, with SMT disabled if
   vulnerable.

Define a set of curated, arch-independent options, each of which is an
aggregation of existing options:

- mitigations=off: Disable all mitigations.

- mitigations=auto: [default] Enable all the default mitigations, but
  leave SMT enabled, even if it's vulnerable.

- mitigations=auto,nosmt: Enable all the default mitigations, disabling
  SMT if needed by a mitigation.

Currently, these options are placeholders which don't actually do
anything.  They will be fleshed out in upcoming patches.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Kosina <jkosina@suse.cz> (on x86)
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-arch@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Steven Price <steven.price@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Link: https://lkml.kernel.org/r/b07a8ef9b7c5055c3a4637c87d07c296d5016fe0.1555085500.git.jpoimboe@redhat.com
[bwh: Backported to 4.4:
 - Drop the auto,nosmt option which we can't support
 - Adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-16 19:45:15 +02:00
..
bpf bpf: Prevent memory disambiguation attack 2018-12-17 21:55:15 +01:00
configs kconfig: tinyconfig: provide whole choice blocks to avoid warnings 2016-09-24 10:07:42 +02:00
debug kdb: use memmove instead of overlapping memcpy 2018-12-13 09:21:29 +01:00
events perf/core: Restore mmap record type correctly 2019-04-27 09:33:56 +02:00
gcov gcov: disable for COMPILE_TEST 2018-01-23 19:50:10 +01:00
irq genirq: Prevent use-after-free and work list corruption 2019-05-16 19:45:04 +02:00
livepatch livepatch: x86: fix relocation computation with kASLR 2015-11-11 17:36:04 +01:00
locking Revert "locking/lockdep: Add debug_locks check in __lock_downgrade()" 2019-04-27 09:34:02 +02:00
power PM / Hibernate: Call flush_icache_range() on pages restored in-place 2019-04-03 06:23:24 +02:00
printk printk: Fix panic caused by passing log_buf_len to command line 2018-11-21 09:27:35 +01:00
rcu rcu: Do RCU GP kthread self-wakeup from softirq and interrupt 2019-03-23 08:44:39 +01:00
sched sched: Add sched_smt_active() 2019-05-16 19:45:11 +02:00
time timer/debug: Change /proc/timer_stats from 0644 to 0600 2019-05-16 19:45:05 +02:00
trace trace: Fix preempt_enable_no_resched() abuse 2019-05-16 19:44:43 +02:00
.gitignore certs: add .gitignore to stop git nagging about x509_certificate_list 2015-10-21 15:18:35 +01:00
acct.c kernel/acct.c: fix the acct->needcheck check in check_free_space() 2018-01-10 09:27:08 +01:00
async.c kernel/async.c: revert "async: simplify lowest_in_progress()" 2018-02-16 20:09:45 +01:00
audit.c audit: return on memory error to avoid null pointer dereference 2018-05-30 07:49:16 +02:00
audit.h audit: audit_tree_match can be boolean 2015-11-04 08:23:51 -05:00
audit_fsnotify.c audit: clean simple fsnotify implementation 2015-08-06 16:14:53 -04:00
audit_tree.c audit: audit_tree_match can be boolean 2015-11-04 08:23:51 -05:00
audit_watch.c audit: fix use-after-free in audit_add_watch 2018-09-26 08:35:08 +02:00
auditfilter.c audit: allow not equal op for audit by executable 2018-08-06 16:24:38 +02:00
auditsc.c audit: allow not equal op for audit by executable 2018-08-06 16:24:38 +02:00
backtracetest.c
bounds.c kbuild: fix kernel/bounds.c 'W=1' warning 2018-11-21 09:27:35 +01:00
capability.c exec: Ensure mm->user_ns contains the execed files 2017-01-06 11:16:14 +01:00
cgroup.c cgroup: Fix deadlock in cpu hotplug path 2018-10-13 09:11:33 +02:00
cgroup_freezer.c cgroup: fix handling of multi-destination migration from subtree_control enabling 2015-12-03 10:18:21 -05:00
cgroup_pids.c cgroup_pids: don't account for the root cgroup 2015-12-03 10:18:21 -05:00
compat.c compat: cleanup coding in compat_get_bitmap() and compat_put_bitmap() 2015-06-04 23:57:18 +02:00
configs.c
context_tracking.c context_tracking: avoid irq_save/irq_restore on guest entry and exit 2015-11-10 12:06:23 +01:00
cpu.c cpu/speculation: Add 'mitigations=' cmdline option 2019-05-16 19:45:15 +02:00
cpu_pm.c kernel/cpu_pm: fix cpu_cluster_pm_exit comment 2015-09-03 02:42:20 +02:00
cpuset.c sched/cpuset/pm: Fix cpuset vs. suspend-resume bugs 2017-10-12 11:27:35 +02:00
crash_dump.c
cred.c cred: Reject inodes with invalid ids in set_create_file_as() 2016-09-15 08:27:49 +02:00
delayacct.c
dma.c
elfcore.c
exec_domain.c Remove rest of exec domains. 2015-04-12 21:03:31 +02:00
exit.c kernel/exit.c: release ptraced tasks before zap_pid_ns_processes 2019-02-06 19:43:07 +01:00
extable.c kernel/extable.c: mark core_kernel_text notrace 2017-07-21 07:44:56 +02:00
fork.c fork: record start_time late 2019-01-13 10:05:32 +01:00
freezer.c
futex.c futex: Ensure that futex address is aligned in handle_futex_death() 2019-04-03 06:23:15 +02:00
futex_compat.c ptrace: use fsuid, fsgid, effective creds for fs access checks 2016-02-25 12:01:16 -08:00
groups.c kernel: make groups_sort calling a responsibility group_info allocators 2018-01-10 09:27:10 +01:00
hung_task.c kernel/hung_task.c: break RCU locks based on jiffies 2019-02-20 10:13:14 +01:00
irq_work.c treewide: Remove old email address 2015-11-23 09:44:58 +01:00
jump_label.c jump_label: Invoke jump_label_test() via early_initcall() 2017-12-16 10:33:55 +01:00
kallsyms.c
kcmp.c ptrace: use fsuid, fsgid, effective creds for fs access checks 2016-02-25 12:01:16 -08:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks locking/qrwlock: Rename QUEUE_RWLOCK to QUEUED_RWLOCKS 2015-05-12 09:46:00 +02:00
Kconfig.preempt
kexec.c kexec: use file name as the output message prefix 2015-11-06 17:50:42 -08:00
kexec_core.c kexec: use file name as the output message prefix 2015-11-06 17:50:42 -08:00
kexec_file.c kexec: fix double-free when failing to relocate the purgatory 2016-09-24 10:07:36 +02:00
kexec_internal.h kexec: split kexec_file syscall code to kexec_file.c 2015-09-10 13:29:01 -07:00
kmod.c kmod: don't run async usermode helper as a child of kworker thread 2015-10-23 17:55:10 +09:00
kprobes.c kprobes: Fix error check when reusing optimized probes 2019-04-27 09:34:02 +02:00
ksysfs.c kexec: split kexec_load syscall from kexec core code 2015-09-10 13:29:01 -07:00
kthread.c kthread, tracing: Don't expose half-written comm when creating kthreads 2018-09-09 20:04:34 +02:00
latencytop.c
Makefile sys_membarrier(): system-wide memory barrier (generic, x86) 2015-09-11 15:21:34 -07:00
membarrier.c Fix: Disable sys_membarrier when nohz_full is enabled 2017-03-12 06:37:26 +01:00
memremap.c mm, devm_memremap_pages: kill mapping "System RAM" support 2019-01-13 10:05:32 +01:00
module-internal.h
module.c module: exclude SHN_UNDEF symbols from kallsyms api 2018-10-10 08:52:07 +02:00
module_signing.c KEYS: Merge the type-specific data with the payload data 2015-10-21 15:18:36 +01:00
notifier.c Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 08:40:25 -07:00
nsproxy.c
padata.c padata: free correct variable 2017-05-20 14:27:02 +02:00
panic.c kernel/panic.c: add missing \n 2017-07-05 14:37:19 +02:00
params.c Nothing exciting, minor tweaks and cleanups. 2015-11-09 15:53:39 -08:00
pid.c pidns: disable pid allocation if pid_ns_prepare_proc() is failed in alloc_pid() 2018-04-13 19:50:03 +02:00
pid_namespace.c pid_ns: Sleep in TASK_INTERRUPTIBLE in zap_pid_ns_processes 2017-05-25 14:30:11 +02:00
profile.c profile: hide unused functions when !CONFIG_PROC_FS 2018-02-25 11:03:44 +01:00
ptrace.c x86/speculation: Apply IBPB more strictly to avoid cross-process data leak 2019-05-16 19:45:09 +02:00
range.c
reboot.c kexec: split kexec_load syscall from kexec core code 2015-09-10 13:29:01 -07:00
relay.c kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE 2018-05-30 07:49:00 +02:00
resource.c resource: fix integer overflow at reallocation 2018-04-24 09:32:05 +02:00
seccomp.c seccomp: Move speculation migitation control to arch code 2018-07-25 10:18:27 +02:00
signal.c signal: Restore the stop PTRACE_EVENT_EXIT 2019-02-20 10:13:23 +01:00
smp.c mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
smpboot.c stop_machine: Kill smp_hotplug_thread->pre_unpark, introduce stop_machine_unpark() 2015-10-20 10:23:55 +02:00
smpboot.h
softirq.c
stacktrace.c
stop_machine.c kernel: remove stop_machine() Kconfig dependency 2015-12-12 10:15:34 -08:00
sys.c sys: don't hold uts_sem while accessing userspace memory 2018-09-09 20:04:35 +02:00
sys_ni.c mm: mlock: add new mlock system call 2015-11-05 19:34:48 -08:00
sysctl.c kernel/sysctl.c: fix out-of-bounds access when setting file-max 2019-04-27 09:34:02 +02:00
sysctl_binary.c fs/coredump: prevent fsuid=0 dumps into user-controlled directories 2016-04-12 09:08:58 -07:00
task_work.c task_work: remove fifo ordering guarantee 2015-09-05 13:46:58 -07:00
taskstats.c
test_kprobes.c
torture.c torture: Consolidate cond_resched_rcu_qs() into stutter_wait() 2015-10-06 11:25:01 -07:00
tracepoint.c tracepoint: Do not warn on ENOMEM 2018-05-16 10:06:47 +02:00
tsacct.c
uid16.c kernel: make groups_sort calling a responsibility group_info allocators 2018-01-10 09:27:10 +01:00
up.c
user-return-notifier.c
user.c
user_namespace.c userns: move user access out of the mutex 2018-09-09 20:04:35 +02:00
utsname.c
utsname_sysctl.c sys: don't hold uts_sem while accessing userspace memory 2018-09-09 20:04:35 +02:00
watchdog.c kernel/watchdog: use nmi registers snapshot in hardlockup handler 2017-01-06 11:16:16 +01:00
workqueue.c workqueue: use put_device() instead of kfree() 2018-05-30 07:49:04 +02:00
workqueue_internal.h workqueue: Fix NULL pointer dereference 2017-11-15 17:13:11 +01:00