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* perf tools: Add libdw DWARF post unwind support for ARMJean Pihet2014-05-162-0/+41
| | | | | | | | | | | | | | | | | | | | | Adding libdw DWARF post unwind support, which is part of elfutils-devel/libdw-dev package from version 0.158. The new code is contained in unwin-libdw.c object, and implements unwind__get_entries unwind interface function. Signed-off-by: Jean Pihet <jean.pihet@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1400229672-16104-4-git-send-email-jean.pihet@linaro.org Signed-off-by: Jiri Olsa <jolsa@kernel.org>
* perf tests: Add dwarf unwind test on ARMJean Pihet2014-05-167-5/+69
| | | | | | | | | | | | | | | | | | | | | | | | Adding dwarf unwind test, that setups live machine data over the perf test thread and does the remote unwind. Need to use -fno-optimize-sibling-calls for test compilation, otherwise 'krava_*' function calls are optimized into jumps and omitted from the stack unwind. So far it was enabled only for x86. Signed-off-by: Jean Pihet <jean.pihet@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1400229672-16104-3-git-send-email-jean.pihet@linaro.org Signed-off-by: Jiri Olsa <jolsa@kernel.org>
* perf tests: Introduce perf_regs_load function on ARMJean Pihet2014-05-163-0/+61
| | | | | | | | | | | | | | | | | | | | | Introducing perf_regs_load function, which is going to be used for dwarf unwind test in following patches. It takes single argument as a pointer to the regs dump buffer and populates it with current registers values. Signed-off-by: Jean Pihet <jean.pihet@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1400229672-16104-2-git-send-email-jean.pihet@linaro.org Signed-off-by: Jiri Olsa <jolsa@kernel.org>
* perf tools: Consolidate types.h for ARM and ARM64Jean Pihet2014-05-162-2/+2
| | | | | | | | | Prevents a build breakage since commit d944c4eebcf4c0d5e5d9728fec110cbf0047ad7f 'tools: Consolidate types.h' Signed-off-by: Jean Pihet <jean.pihet@linaro.org> Link: http://lkml.kernel.org/r/1400229672-16104-1-git-send-email-jean.pihet@linaro.org Signed-off-by: Jiri Olsa <jolsa@kernel.org>
* perf session: Fix possible null pointer dereference in session.cMasanari Iida2014-05-161-2/+3
| | | | | | | | | | | | | cppcheck detected following warning: [tools/perf/util/session.c:1628] -> [tools/perf/util/session.c:1632]: (warning) Possible null pointer dereference: session - otherwise it is redundant to check it against null. In order to avoide null pointer, check the pointer before use. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Link: http://lkml.kernel.org/r/1400087618-13628-1-git-send-email-standby24x7@gmail.com Signed-off-by: Jiri Olsa <jolsa@kernel.org>
* perf sched: Cleanup, remove unused variables in map_switch_event()Dongsheng Yang2014-05-161-4/+2
| | | | | | | | | In map_switch_event(), we don't care the previous process currently, this patch remove the infomation we get but not used. Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com> Link: http://lkml.kernel.org/r/1400218625-14613-1-git-send-email-yangds.fnst@cn.fujitsu.com Signed-off-by: Jiri Olsa <jolsa@kernel.org>
* perf sched: Remove nr_state_machine_bugs in perf latencyDongsheng Yang2014-05-161-11/+8
| | | | | | | | | | | As we do not use .success in sched_wakeup event any more, then we can not guarantee that the task when wakeup event happen is out of run queue. So the message of nr_state_machine_bugs is not correct. Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com> Link: http://lkml.kernel.org/r/1399945101-21736-1-git-send-email-yangds.fnst@cn.fujitsu.com Signed-off-by: Jiri Olsa <jolsa@kernel.org>
* perf tools: Remove usage of trace_sched_wakeup(.success)Peter Zijlstra2014-05-122-9/+1
| | | | | | | | | | | | | trace_sched_wakeup(.success) is a dead argument and has been for ages, the only reason its still there is because of brain dead software, which apparently includes perf tools There's a few more instances in pearly snake shit, but that's not supported as far as I care anyhow, so let that bitrot. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140512181946.GG13467@laptop.programming.kicks-ass.net Signed-off-by: Jiri Olsa <jolsa@kernel.org>
* Merge tag 'perf-core-for-mingo' of ↵Ingo Molnar2014-05-1213-152/+90
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf into perf/core Pull perf/core improvements and fixes from Jiri Olsa: * Propagate exit status of a command line workload for record command (Namhyung Kim) * Use tid for finding thread (Namhyung Kim) * Clarify the output of perf sched map plus small sched command fixies (Dongsheng Yang) Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf tools: Use tid for finding threadNamhyung Kim2014-05-127-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I believe that passing pid (instead of tid) as the 3rd arg of the machine__find*_thread() was to find a main thread so that it can search proper map group for symbols. However with the map sharing patch applied, it now can do it in any thread. It fixes a bug when each thread has different name, it only reports a main thread for samples in other threads. Cc: Adrian Hunter <adrian.hunter@intel.com> Acked-by: David Ahern <dsahern@gmail.com> Acked-by: Stephane Eranian <eranian@google.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/1399856202-26221-1-git-send-email-namhyung@kernel.org Signed-off-by: Jiri Olsa <jolsa@kernel.org>
| * perf tools: Get rid of on_exit() feature testNamhyung Kim2014-05-125-64/+0
| | | | | | | | | | | | | | | | | | | | | | | | The on_exit() function was only used in perf record but it's gone in previous patch. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Stephane Eranian <eranian@google.com> Cc: Bernhard Rosenkraenzer <Bernhard.Rosenkranzer@linaro.org> Cc: Irina Tirdea <irina.tirdea@intel.com> Link: http://lkml.kernel.org/r/1399855645-25815-2-git-send-email-namhyung@kernel.org Signed-off-by: Jiri Olsa <jolsa@kernel.org>
| * perf record: Propagate exit status of a command line workloadNamhyung Kim2014-05-121-67/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently perf record doesn't propagate the exit status of a workload given by the command line. But sometimes it'd useful if it's propagated so that a monitoring script can handle errors appropriately. To do that, it moves most of logic out of the exit handlers and run them directly in the __cmd_record(). The only thing needs to be done in the handler is propagating terminating signal so that the shell can terminate its loop properly when Ctrl-C was pressed. Also it cleaned up the resource management code in record__exit(). With this change, perf record returns the child exit status in case of normal termination and send signal to itself when terminated by signal. Example run of Stephane's case: $ perf record true && echo yes || echo no [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.013 MB perf.data (~589 samples) ] yes $ perf record false && echo yes || echo no [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.013 MB perf.data (~589 samples) ] no Jiri's case (error in parent): $ perf record -m 10G true && echo yes || echo no rounding mmap pages size to 17179869184 bytes (4194304 pages) failed to mmap with 12 (Cannot allocate memory) no $ ulimit -n 6 $ perf record sleep 1 && echo yes || echo no failed to create 'go' pipe: Too many open files Couldn't run the workload! no And Peter's case (interrupted by signal): $ while :; do perf record sleep 1; done ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.014 MB perf.data (~593 samples) ] Reported-by: Stephane Eranian <eranian@google.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Stephane Eranian <eranian@google.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1399855645-25815-1-git-send-email-namhyung@kernel.org Signed-off-by: Jiri Olsa <jolsa@kernel.org>
| * perf tools: Clarify the output of perf sched map.Dongsheng2014-05-121-15/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In output of perf sched map, any shortname of thread will be explained at the first time when it appear. Example: *A0 228836.978985 secs A0 => perf:23032 *. A0 228836.979016 secs B0 => swapper:0 . *C0 228836.979099 secs C0 => migration/3:22 *A0 . C0 228836.979115 secs A0 . *. 228836.979115 secs But B0, which is explained as swapper:0 did not appear in the left part of output. Instead, we use '.' as the shortname of swapper:0. So the comment of "B0 => swapper:0" is not easy to understand. This patch clarify the output of perf sched map with not allocating one letter-number shortname for swapper:0 and print ". => swapper:0" as the explanation for swapper:0. Example: *A0 228836.978985 secs A0 => perf:23032 * . A0 228836.979016 secs . => swapper:0 . *B0 228836.979099 secs B0 => migration/3:22 *A0 . B0 228836.979115 secs A0 . * . 228836.979115 secs A0 *C0 . 228836.979225 secs C0 => ksoftirqd/2:18 A0 *D0 . 228836.979236 secs D0 => rcu_sched:7 Signed-off-by: Dongsheng <yangds.fnst@cn.fujitsu.com> Acked-by: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/1399354741-19522-1-git-send-email-yangds.fnst@cn.fujitsu.com [ small style fixes to make checkpatch happy ] Signed-off-by: Jiri Olsa <jolsa@kernel.org>
| * perf tools: Adapt the TASK_STATE_TO_CHAR_STR to new value in kernel space.Dongsheng2014-05-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | Currently, TASK_STATE_TO_CHAR_STR in kernel space is already expanded to RSDTtZXxKWP, but it is still RSDTtZX in perf sched tool. This patch update TASK_STATE_TO_CHAR_STR to the new value in kernel space. Signed-off-by: Dongsheng <yangds.fnst@cn.fujitsu.com> Link: http://lkml.kernel.org/r/6d2f55dc1e02c1e29a5d70bfeb9d6e8863caf2aa.1399273302.git.yangds.fnst@cn.fujitsu.com Signed-off-by: Jiri Olsa <jolsa@kernel.org>
| * perf tools: Add missing event for perf sched record.Dongsheng2014-05-121-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | We should record and process sched:sched_wakeup_new event in perf sched tool, but currently, there is the process function for it, without recording it in record subcommand. This patch add -e sched:sched_wakeup_new to perf sched record. Signed-off-by: Dongsheng <yangds.fnst@cn.fujitsu.com> Link: http://lkml.kernel.org/r/710c6edd2162b2cea1711443f54de47c0210d9fd.1399273302.git.yangds.fnst@cn.fujitsu.com Signed-off-by: Jiri Olsa <jolsa@kernel.org>
* | perf: Simplify perf_event_exit_task_context()Peter Zijlstra2014-05-071-16/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of jumping through hoops to make sure to find (and exit) each event, do it the simple straight fwd way. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-tij931199thfkys8vbnokdpf@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | perf: Rework free pathsPeter Zijlstra2014-05-071-26/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Primarily make perf_event_release_kernel() into put_event(), this will allow kernel space to create per-task inherited events, and is safer in general. Also, document the free_event() assumptions. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-rk9pvr6e1d0559lxstltbztc@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | perf: Validate locking assumptionPeter Zijlstra2014-05-071-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Document and validate the locking assumption of event_sched_in(). Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-sybq1publ9xt5no77cwvi0eo@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | perf: Always destroy groups on exitPeter Zijlstra2014-05-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 38b435b16c36 ("perf: Fix tear-down of inherited group events") states that we need to destroy groups for inherited events, but it doesn't make any sense to not also destroy groups for normal events. And while it usually makes no difference (the normal events won't leak, and its very likely all the group events will die in quick succession) it does make the code more consistent and closes a potential hole for trouble. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-426egt8zmsm12d2q8k2xz4tt@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | perf: Ensure consistent inherit state in groupsPeter Zijlstra2014-05-071-3/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make sure all events in a group have the same inherit state. It was possible for group leaders to have inherit set while sibling events would not have inherit set. In this case we'd still inherit the siblings, leading to some non-fatal weirdness. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-r32tt8yldvic3jlcghd3g35u@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge branch 'perf/urgent' into perf/core, to avoid conflictsIngo Molnar2014-05-07588-3533/+6142
|\ \ | |/ |/| | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf/x86/intel: Fix Silvermont's event constraintsYan, Zheng2014-05-071-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | Event 0x013c is not the same as fixed counter2, remove it from Silvermont's event constraints. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1398755081-12471-1-git-send-email-zheng.z.yan@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf: Fix perf_event_init_context()Peter Zijlstra2014-05-071-0/+2
| | | | | | | | | | | | | | | | | | | | | | perf_pin_task_context() can return NULL but perf_event_init_context() assumes it will not, correct this. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Link: http://lkml.kernel.org/r/20140505171428.GU26782@laptop.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf: Fix race in removing an eventPeter Zijlstra2014-05-071-21/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When removing a (sibling) event we do: raw_spin_lock_irq(&ctx->lock); perf_group_detach(event); raw_spin_unlock_irq(&ctx->lock); <hole> perf_remove_from_context(event); raw_spin_lock_irq(&ctx->lock); ... raw_spin_unlock_irq(&ctx->lock); Now, assuming the event is a sibling, it will be 'unreachable' for things like ctx_sched_out() because that iterates the groups->siblings, and we just unhooked the sibling. So, if during <hole> we get ctx_sched_out(), it will miss the event and not call event_sched_out() on it, leaving it programmed on the PMU. The subsequent perf_remove_from_context() call will find the ctx is inactive and only call list_del_event() to remove the event from all other lists. Hereafter we can proceed to free the event; while still programmed! Close this hole by moving perf_group_detach() inside the same ctx->lock region(s) perf_remove_from_context() has. The condition on inherited events only in __perf_event_exit_task() is likely complete crap because non-inherited events are part of groups too and we're tearing down just the same. But leave that for another patch. Most-likely-Fixes: e03a9a55b4e ("perf: Change close() semantics for group events") Reported-by: Vince Weaver <vincent.weaver@maine.edu> Tested-by: Vince Weaver <vincent.weaver@maine.edu> Much-staring-at-traces-by: Vince Weaver <vincent.weaver@maine.edu> Much-staring-at-traces-by: Thomas Gleixner <tglx@linutronix.de> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140505093124.GN17778@laptop.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * Merge branch 'akpm' (incoming from Andrew)Linus Torvalds2014-05-0619-91/+147
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge misc fixes from Andrew Morton: "13 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: agp: info leak in agpioc_info_wrap() fs/affs/super.c: bugfix / double free fanotify: fix -EOVERFLOW with large files on 64-bit slub: use sysfs'es release mechanism for kmem_cache revert "mm: vmscan: do not swap anon pages just because free+file is low" autofs: fix lockref lookup mm: filemap: update find_get_pages_tag() to deal with shadow entries mm/compaction: make isolate_freepages start at pageblock boundary MAINTAINERS: zswap/zbud: change maintainer email address mm/page-writeback.c: fix divide by zero in pos_ratio_polynom hugetlb: ensure hugepage access is denied if hugepages are not supported slub: fix memcg_propagate_slab_attrs drivers/rtc/rtc-pcf8523.c: fix month definition
| | * agp: info leak in agpioc_info_wrap()Dan Carpenter2014-05-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On 64 bit systems the agp_info struct has a 4 byte hole between ->agp_mode and ->aper_base. We need to clear it to avoid disclosing stack information to userspace. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * fs/affs/super.c: bugfix / double freeFabian Frederick2014-05-061-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 842a859db26b ("affs: use ->kill_sb() to simplify ->put_super() and failure exits of ->mount()") adds .kill_sb which frees sbi but doesn't remove sbi free in case of parse_options error causing double free+random crash. Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> [3.14.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * fanotify: fix -EOVERFLOW with large files on 64-bitWill Woods2014-05-061-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On 64-bit systems, O_LARGEFILE is automatically added to flags inside the open() syscall (also openat(), blkdev_open(), etc). Userspace therefore defines O_LARGEFILE to be 0 - you can use it, but it's a no-op. Everything should be O_LARGEFILE by default. But: when fanotify does create_fd() it uses dentry_open(), which skips all that. And userspace can't set O_LARGEFILE in fanotify_init() because it's defined to 0. So if fanotify gets an event regarding a large file, the read() will just fail with -EOVERFLOW. This patch adds O_LARGEFILE to fanotify_init()'s event_f_flags on 64-bit systems, using the same test as open()/openat()/etc. Addresses https://bugzilla.redhat.com/show_bug.cgi?id=696821 Signed-off-by: Will Woods <wwoods@redhat.com> Acked-by: Eric Paris <eparis@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * slub: use sysfs'es release mechanism for kmem_cacheChristoph Lameter2014-05-064-24/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | debugobjects warning during netfilter exit: ------------[ cut here ]------------ WARNING: CPU: 6 PID: 4178 at lib/debugobjects.c:260 debug_print_object+0x8d/0xb0() ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x20 Modules linked in: CPU: 6 PID: 4178 Comm: kworker/u16:2 Tainted: G W 3.11.0-next-20130906-sasha #3984 Workqueue: netns cleanup_net Call Trace: dump_stack+0x52/0x87 warn_slowpath_common+0x8c/0xc0 warn_slowpath_fmt+0x46/0x50 debug_print_object+0x8d/0xb0 __debug_check_no_obj_freed+0xa5/0x220 debug_check_no_obj_freed+0x15/0x20 kmem_cache_free+0x197/0x340 kmem_cache_destroy+0x86/0xe0 nf_conntrack_cleanup_net_list+0x131/0x170 nf_conntrack_pernet_exit+0x5d/0x70 ops_exit_list+0x5e/0x70 cleanup_net+0xfb/0x1c0 process_one_work+0x338/0x550 worker_thread+0x215/0x350 kthread+0xe7/0xf0 ret_from_fork+0x7c/0xb0 Also during dcookie cleanup: WARNING: CPU: 12 PID: 9725 at lib/debugobjects.c:260 debug_print_object+0x8c/0xb0() ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x20 Modules linked in: CPU: 12 PID: 9725 Comm: trinity-c141 Not tainted 3.15.0-rc2-next-20140423-sasha-00018-gc4ff6c4 #408 Call Trace: dump_stack (lib/dump_stack.c:52) warn_slowpath_common (kernel/panic.c:430) warn_slowpath_fmt (kernel/panic.c:445) debug_print_object (lib/debugobjects.c:262) __debug_check_no_obj_freed (lib/debugobjects.c:697) debug_check_no_obj_freed (lib/debugobjects.c:726) kmem_cache_free (mm/slub.c:2689 mm/slub.c:2717) kmem_cache_destroy (mm/slab_common.c:363) dcookie_unregister (fs/dcookies.c:302 fs/dcookies.c:343) event_buffer_release (arch/x86/oprofile/../../../drivers/oprofile/event_buffer.c:153) __fput (fs/file_table.c:217) ____fput (fs/file_table.c:253) task_work_run (kernel/task_work.c:125 (discriminator 1)) do_notify_resume (include/linux/tracehook.h:196 arch/x86/kernel/signal.c:751) int_signal (arch/x86/kernel/entry_64.S:807) Sysfs has a release mechanism. Use that to release the kmem_cache structure if CONFIG_SYSFS is enabled. Only slub is changed - slab currently only supports /proc/slabinfo and not /sys/kernel/slab/*. We talked about adding that and someone was working on it. [akpm@linux-foundation.org: fix CONFIG_SYSFS=n build] [akpm@linux-foundation.org: fix CONFIG_SYSFS=n build even more] Signed-off-by: Christoph Lameter <cl@linux.com> Reported-by: Sasha Levin <sasha.levin@oracle.com> Tested-by: Sasha Levin <sasha.levin@oracle.com> Acked-by: Greg KH <greg@kroah.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Pekka Enberg <penberg@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * revert "mm: vmscan: do not swap anon pages just because free+file is low"Johannes Weiner2014-05-061-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 0bf1457f0cfc ("mm: vmscan: do not swap anon pages just because free+file is low") because it introduced a regression in mostly-anonymous workloads, where reclaim would become ineffective and trap every allocating task in direct reclaim. The problem is that there is a runaway feedback loop in the scan balance between file and anon, where the balance tips heavily towards a tiny thrashing file LRU and anonymous pages are no longer being looked at. The commit in question removed the safe guard that would detect such situations and respond with forced anonymous reclaim. This commit was part of a series to fix premature swapping in loads with relatively little cache, and while it made a small difference, the cure is obviously worse than the disease. Revert it. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Rafael Aquini <aquini@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: <stable@kernel.org> [3.12+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * autofs: fix lockref lookupIan Kent2014-05-061-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | autofs needs to be able to see private data dentry flags for its dentrys that are being created but not yet hashed and for its dentrys that have been rmdir()ed but not yet freed. It needs to do this so it can block processes in these states until a status has been returned to indicate the given operation is complete. It does this by keeping two lists, active and expring, of dentrys in this state and uses ->d_release() to keep them stable while it checks the reference count to determine if they should be used. But with the recent lockref changes dentrys being freed sometimes don't transition to a reference count of 0 before being freed so autofs can occassionally use a dentry that is invalid which can lead to a panic. Signed-off-by: Ian Kent <raven@themaw.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * mm: filemap: update find_get_pages_tag() to deal with shadow entriesJohannes Weiner2014-05-063-37/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dave Jones reports the following crash when find_get_pages_tag() runs into an exceptional entry: kernel BUG at mm/filemap.c:1347! RIP: find_get_pages_tag+0x1cb/0x220 Call Trace: find_get_pages_tag+0x36/0x220 pagevec_lookup_tag+0x21/0x30 filemap_fdatawait_range+0xbe/0x1e0 filemap_fdatawait+0x27/0x30 sync_inodes_sb+0x204/0x2a0 sync_inodes_one_sb+0x19/0x20 iterate_supers+0xb2/0x110 sys_sync+0x44/0xb0 ia32_do_call+0x13/0x13 1343 /* 1344 * This function is never used on a shmem/tmpfs 1345 * mapping, so a swap entry won't be found here. 1346 */ 1347 BUG(); After commit 0cd6144aadd2 ("mm + fs: prepare for non-page entries in page cache radix trees") this comment and BUG() are out of date because exceptional entries can now appear in all mappings - as shadows of recently evicted pages. However, as Hugh Dickins notes, "it is truly surprising for a PAGECACHE_TAG_WRITEBACK (and probably any other PAGECACHE_TAG_*) to appear on an exceptional entry. I expect it comes down to an occasional race in RCU lookup of the radix_tree: lacking absolute synchronization, we might sometimes catch an exceptional entry, with the tag which really belongs with the unexceptional entry which was there an instant before." And indeed, not only is the tree walk lockless, the tags are also read in chunks, one radix tree node at a time. There is plenty of time for page reclaim to swoop in and replace a page that was already looked up as tagged with a shadow entry. Remove the BUG() and update the comment. While reviewing all other lookup sites for whether they properly deal with shadow entries of evicted pages, update all the comments and fix memcg file charge moving to not miss shmem/tmpfs swapcache pages. Fixes: 0cd6144aadd2 ("mm + fs: prepare for non-page entries in page cache radix trees") Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reported-by: Dave Jones <davej@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * mm/compaction: make isolate_freepages start at pageblock boundaryVlastimil Babka2014-05-061-10/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The compaction freepage scanner implementation in isolate_freepages() starts by taking the current cc->free_pfn value as the first pfn. In a for loop, it scans from this first pfn to the end of the pageblock, and then subtracts pageblock_nr_pages from the first pfn to obtain the first pfn for the next for loop iteration. This means that when cc->free_pfn starts at offset X rather than being aligned on pageblock boundary, the scanner will start at offset X in all scanned pageblock, ignoring potentially many free pages. Currently this can happen when a) zone's end pfn is not pageblock aligned, or b) through zone->compact_cached_free_pfn with CONFIG_HOLES_IN_ZONE enabled and a hole spanning the beginning of a pageblock This patch fixes the problem by aligning the initial pfn in isolate_freepages() to pageblock boundary. This also permits replacing the end-of-pageblock alignment within the for loop with a simple pageblock_nr_pages increment. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: Heesub Shin <heesub.shin@samsung.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Mel Gorman <mgorman@suse.de> Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Christoph Lameter <cl@linux.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Dongjun Shin <d.j.shin@samsung.com> Cc: Sunghwan Yun <sunghwan.yun@samsung.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * MAINTAINERS: zswap/zbud: change maintainer email addressSeth Jennings2014-05-061-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | sjenning@linux.vnet.ibm.com is no longer a viable entity. Signed-off-by: Seth Jennings <sjennings@variantweb.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * mm/page-writeback.c: fix divide by zero in pos_ratio_polynomRik van Riel2014-05-061-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is possible for "limit - setpoint + 1" to equal zero, after getting truncated to a 32 bit variable, and resulting in a divide by zero error. Using the fully 64 bit divide functions avoids this problem. It also will cause pos_ratio_polynom() to return the correct value when (setpoint - limit) exceeds 2^32. Also uninline pos_ratio_polynom, at Andrew's request. Signed-off-by: Rik van Riel <riel@redhat.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * hugetlb: ensure hugepage access is denied if hugepages are not supportedNishanth Aravamudan2014-05-063-5/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, I am seeing the following when I `mount -t hugetlbfs /none /dev/hugetlbfs`, and then simply do a `ls /dev/hugetlbfs`. I think it's related to the fact that hugetlbfs is properly not correctly setting itself up in this state?: Unable to handle kernel paging request for data at address 0x00000031 Faulting instruction address: 0xc000000000245710 Oops: Kernel access of bad area, sig: 11 [#1] SMP NR_CPUS=2048 NUMA pSeries .... In KVM guests on Power, in a guest not backed by hugepages, we see the following: AnonHugePages: 0 kB HugePages_Total: 0 HugePages_Free: 0 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 64 kB HPAGE_SHIFT == 0 in this configuration, which indicates that hugepages are not supported at boot-time, but this is only checked in hugetlb_init(). Extract the check to a helper function, and use it in a few relevant places. This does make hugetlbfs not supported (not registered at all) in this environment. I believe this is fine, as there are no valid hugepages and that won't change at runtime. [akpm@linux-foundation.org: use pr_info(), per Mel] [akpm@linux-foundation.org: fix build when HPAGE_SHIFT is undefined] Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * slub: fix memcg_propagate_slab_attrsVladimir Davydov2014-05-061-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After creating a cache for a memcg we should initialize its sysfs attrs with the values from its parent. That's what memcg_propagate_slab_attrs is for. Currently it's broken - we clearly muddled root-vs-memcg caches there. Let's fix it up. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| | * drivers/rtc/rtc-pcf8523.c: fix month definitionChris Cui2014-05-061-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PCF8523 uses 1-12 to represent month according to datasheet. link: www.nxp.com/documents/data_sheet/PCF8523.pdf. Signed-off-by: Chris Cui <chris.wei.cui@gmail.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | Merge branch 'for-linus' of ↵Linus Torvalds2014-05-068-234/+125
| |\ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs fixes from Al Viro: "dcache fixes + kvfree() (uninlined, exported by mm/util.c) + posix_acl bugfix from hch" The dcache fixes are for a subtle LRU list corruption bug reported by Miklos Szeredi, where people inside IBM saw list corruptions with the LTP/host01 test. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: nick kvfree() from apparmor posix_acl: handle NULL ACL in posix_acl_equiv_mode dcache: don't need rcu in shrink_dentry_list() more graceful recovery in umount_collect() don't remove from shrink list in select_collect() dentry_kill(): don't try to remove from shrink list expand the call of dentry_lru_del() in dentry_kill() new helper: dentry_free() fold try_prune_one_dentry() fold d_kill() and d_free() fix races between __d_instantiate() and checks of dentry flags
| | * nick kvfree() from apparmorAl Viro2014-05-064-15/+12
| | | | | | | | | | | | | | | | | | too many places open-code it Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * posix_acl: handle NULL ACL in posix_acl_equiv_modeChristoph Hellwig2014-05-061-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Various filesystems don't bother checking for a NULL ACL in posix_acl_equiv_mode, and thus can dereference a NULL pointer when it gets passed one. This usually happens from the NFS server, as the ACL tools never pass a NULL ACL, but instead of one representing the mode bits. Instead of adding boilerplat to all filesystems put this check into one place, which will allow us to remove the check from other filesystems as well later on. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Ben Greear <greearb@candelatech.com> Reported-by: Marco Munderloh <munderl@tnt.uni-hannover.de>, Cc: Chuck Lever <chuck.lever@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * dcache: don't need rcu in shrink_dentry_list()Miklos Szeredi2014-05-031-23/+4
| | | | | | | | | | | | | | | | | | | | | | | | Since now the shrink list is private and nobody can free the dentry while it is on the shrink list, we can remove RCU protection from this. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * more graceful recovery in umount_collect()Al Viro2014-05-031-76/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Start with shrink_dcache_parent(), then scan what remains. First of all, BUG() is very much an overkill here; we are holding ->s_umount, and hitting BUG() means that a lot of interesting stuff will be hanging after that point (sync(2), for example). Moreover, in cases when there had been more than one leak, we'll be better off reporting all of them. And more than just the last component of pathname - %pd is there for just such uses... That was the last user of dentry_lru_del(), so kill it off... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * don't remove from shrink list in select_collect()Al Viro2014-05-031-21/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we find something already on a shrink list, just increment data->found and do nothing else. Loops in shrink_dcache_parent() and check_submounts_and_drop() will do the right thing - everything we did put into our list will be evicted and if there had been nothing, but data->found got non-zero, well, we have somebody else shrinking those guys; just try again. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * dentry_kill(): don't try to remove from shrink listAl Viro2014-05-012-8/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the victim in on the shrink list, don't remove it from there. If shrink_dentry_list() manages to remove it from the list before we are done - fine, we'll just free it as usual. If not - mark it with new flag (DCACHE_MAY_FREE) and leave it there. Eventually, shrink_dentry_list() will get to it, remove the sucker from shrink list and call dentry_kill(dentry, 0). Which is where we'll deal with freeing. Since now dentry_kill(dentry, 0) may happen after or during dentry_kill(dentry, 1), we need to recognize that (by seeing DCACHE_DENTRY_KILLED already set), unlock everything and either free the sucker (in case DCACHE_MAY_FREE has been set) or leave it for ongoing dentry_kill(dentry, 1) to deal with. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * expand the call of dentry_lru_del() in dentry_kill()Al Viro2014-04-301-1/+6
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * new helper: dentry_free()Al Viro2014-04-301-5/+10
| | | | | | | | | | | | | | | | | | | | | The part of old d_free() that dealt with actual freeing of dentry. Taken out of dentry_kill() into a separate function. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * fold try_prune_one_dentry()Al Viro2014-04-301-50/+25
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * fold d_kill() and d_free()Al Viro2014-04-301-52/+24
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| | * fix races between __d_instantiate() and checks of dentry flagsAl Viro2014-04-192-5/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | in non-lazy walk we need to be careful about dentry switching from negative to positive - both ->d_flags and ->d_inode are updated, and in some places we might see only one store. The cases where dentry has been obtained by dcache lookup with ->i_mutex held on parent are safe - ->d_lock and ->i_mutex provide all the barriers we need. However, there are several places where we run into trouble: * do_last() fetches ->d_inode, then checks ->d_flags and assumes that inode won't be NULL unless d_is_negative() is true. Race with e.g. creat() - we might have fetched the old value of ->d_inode (still NULL) and new value of ->d_flags (already not DCACHE_MISS_TYPE). Lin Ming has observed and reported the resulting oops. * a bunch of places checks ->d_inode for being non-NULL, then checks ->d_flags for "is it a symlink". Race with symlink(2) in case if our CPU sees ->d_inode update first - we see non-NULL there, but ->d_flags still contains DCACHE_MISS_TYPE instead of DCACHE_SYMLINK_TYPE. Result: false negative on "should we follow link here?", with subsequent unpleasantness. Cc: stable@vger.kernel.org # 3.13 and 3.14 need that one Reported-and-tested-by: Lin Ming <minggr@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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