android_kernel_motorola_sm6375/kernel
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Dan Williams a95c90f1e2 mm, devm_memremap_pages: fix shutdown handling
The last step before devm_memremap_pages() returns success is to allocate
a release action, devm_memremap_pages_release(), to tear the entire setup
down.  However, the result from devm_add_action() is not checked.

Checking the error from devm_add_action() is not enough.  The api
currently relies on the fact that the percpu_ref it is using is killed by
the time the devm_memremap_pages_release() is run.  Rather than continue
this awkward situation, offload the responsibility of killing the
percpu_ref to devm_memremap_pages_release() directly.  This allows
devm_memremap_pages() to do the right thing relative to init failures and
shutdown.

Without this change we could fail to register the teardown of
devm_memremap_pages().  The likelihood of hitting this failure is tiny as
small memory allocations almost always succeed.  However, the impact of
the failure is large given any future reconfiguration, or disable/enable,
of an nvdimm namespace will fail forever as subsequent calls to
devm_memremap_pages() will fail to setup the pgmap_radix since there will
be stale entries for the physical address range.

An argument could be made to require that the ->kill() operation be set in
the @pgmap arg rather than passed in separately.  However, it helps code
readability, tracking the lifetime of a given instance, to be able to grep
the kill routine directly at the devm_memremap_pages() call site.

Link: http://lkml.kernel.org/r/154275558526.76910.7535251937849268605.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Fixes: e8d5134833 ("memremap: change devm_memremap_pages interface...")
Reviewed-by: "Jérôme Glisse" <jglisse@redhat.com>
Reported-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28 12:11:47 -08:00
..
bpf Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2018-12-20 17:31:36 -08:00
cgroup cgroups: Replace synchronize_sched() with synchronize_rcu() 2018-12-01 12:38:49 -08:00
configs
debug
dma dma-direct: do not include SME mask in the DMA supported check 2018-12-17 18:02:11 +01:00
events Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-12-26 14:45:18 -08:00
gcov
irq genirq/affinity: Add is_managed to struct irq_affinity_desc 2018-12-19 11:32:08 +01:00
livepatch livepatch: Replace synchronize_sched() with synchronize_rcu() 2018-12-01 12:38:50 -08:00
locking Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-12-26 14:25:52 -08:00
power mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
printk Printk changes for 4.21 2018-12-27 11:24:43 -08:00
rcu rcutorture: Don't do busted forward-progress testing 2018-12-01 12:45:42 -08:00
sched sched/fair: Fix warning on non-SMP build 2018-12-27 10:40:15 -08:00
time Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-12-25 15:44:08 -08:00
trace Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-12-27 13:04:52 -08:00
.gitignore
acct.c
async.c
audit.c audit: remove duplicated include from audit.c 2018-12-14 12:09:30 -05:00
audit.h
audit_fsnotify.c
audit_tree.c
audit_watch.c
auditfilter.c
auditsc.c
backtracetest.c
bounds.c
capability.c
compat.c
configs.c
context_tracking.c
cpu.c
cpu_pm.c
crash_core.c
crash_dump.c
cred.c
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c
extable.c
fail_function.c
fork.c mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
freezer.c
futex.c futex: Cure exit race 2018-12-18 23:13:15 +01:00
futex_compat.c
groups.c
hung_task.c
iomem.c
irq_work.c
jump_label.c
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c kernel/kcov.c: mark funcs in __sanitizer_cov_trace_pc() as notrace 2018-11-30 14:56:14 -08:00
kexec.c
kexec_core.c mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
kexec_file.c kexec_file: kexec_walk_memblock() only walks a dedicated region at kdump 2018-12-06 14:38:50 +00:00
kexec_internal.h
kmod.c
kprobes.c Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-12-26 14:45:18 -08:00
ksysfs.c
kthread.c
latencytop.c
Makefile
memremap.c mm, devm_memremap_pages: fix shutdown handling 2018-12-28 12:11:47 -08:00
module-internal.h
module.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-12-27 13:04:52 -08:00
module_signing.c
notifier.c
nsproxy.c
padata.c
panic.c Printk changes for 4.21 2018-12-27 11:24:43 -08:00
params.c
pid.c
pid_namespace.c
profile.c
ptrace.c ptrace: Remove unused ptrace_may_access_sched() and MODE_IBRS 2018-11-28 11:57:11 +01:00
range.c
reboot.c
relay.c
resource.c
rseq.c
seccomp.c
signal.c
smp.c
smpboot.c
smpboot.h
softirq.c
stackleak.c stackleak: Mark stackleak_track_stack() as notrace 2018-12-05 19:31:44 -08:00
stacktrace.c
stop_machine.c
sys.c arm64: add prctl control for resetting ptrauth keys 2018-12-13 16:42:46 +00:00
sys_ni.c
sysctl.c
sysctl_binary.c
task_work.c
taskstats.c
test_kprobes.c
torture.c torture: Remove unnecessary "ret" variables 2018-12-01 12:45:35 -08:00
tracepoint.c
tsacct.c
ucount.c
uid16.c
uid16.h
umh.c
up.c
user-return-notifier.c
user.c
user_namespace.c
utsname.c
utsname_sysctl.c
watchdog.c
watchdog_hld.c
workqueue.c
workqueue_internal.h