kernel/linux.git/include/linux, branch v4.9.168

genirq: Avoid summation loops for /proc/stat

2019-04-05T20:29:12+00:00

[ Upstream commit 1136b0728969901a091f0471968b2b76ed14d9ad ] Waiman reported that on large systems with a large amount of interrupts the readout of /proc/stat takes a long time to sum up the interrupt statistics. In principle this is not a problem. but for unknown reasons some enterprise quality software reads /proc/stat with a high frequency. The reason for this is that interrupt statistics are accounted per cpu. So the /proc/stat logic has to sum up the interrupt stats for each interrupt. This can be largely avoided for interrupts which are not marked as 'PER_CPU' interrupts by simply adding a per interrupt summation counter which is incremented along with the per interrupt per cpu counter. The PER_CPU interrupts need to avoid that and use only per cpu accounting because they share the interrupt number and the interrupt descriptor and concurrent updates would conflict or require unwanted synchronization. Reported-by: Waiman Long Signed-off-by: Thomas Gleixner Reviewed-by: Waiman Long Reviewed-by: Marc Zyngier Reviewed-by: Davidlohr Bueso Cc: Matthew Wilcox Cc: Andrew Morton Cc: Alexey Dobriyan Cc: Kees Cook Cc: linux-fsdevel@vger.kernel.org Cc: Davidlohr Bueso Cc: Miklos Szeredi Cc: Daniel Colascione Cc: Dave Chinner Cc: Randy Dunlap Link: https://lkml.kernel.org/r/20190208135020.925487496@linutronix.de 8<------------- v2: Undo the unintentional layout change of struct irq_desc. include/linux/irqdesc.h | 1 + kernel/irq/chip.c | 12 ++++++++++-- kernel/irq/internals.h | 8 +++++++- kernel/irq/irqdesc.c | 7 ++++++- 4 files changed, 24 insertions(+), 4 deletions(-) Signed-off-by: Sasha Levin

include/linux/relay.h: fix percpu annotation in struct rchan

2019-04-05T20:29:06+00:00

[ Upstream commit 62461ac2e5b6520b6d65fc6d7d7b4b8df4b848d8 ] The percpu member of this structure is declared as: struct ... ** __percpu member; So its type is: __percpu pointer to pointer to struct ... But looking at how it's used, its type should be: pointer to __percpu pointer to struct ... and it should thus be declared as: struct ... * __percpu *member; So fix the placement of '__percpu' in the definition of this structures. This silents a few Sparse's warnings like: warning: incorrect type in initializer (different address spaces) expected void const [noderef] *__vpp_verify got struct sched_domain ** Link: http://lkml.kernel.org/r/20190118144902.79065-1-luc.vanoostenryck@gmail.com Fixes: 017c59c042d01 ("relay: Use per CPU constructs for the relay channel buffer pointers") Signed-off-by: Luc Van Oostenryck Cc: Jens Axboe Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

tracing: kdb: Fix ftdump to not sleep

2019-04-05T20:29:05+00:00

[ Upstream commit 31b265b3baaf55f209229888b7ffea523ddab366 ] As reported back in 2016-11 [1], the "ftdump" kdb command triggers a BUG for "sleeping function called from invalid context". kdb's "ftdump" command wants to call ring_buffer_read_prepare() in atomic context. A very simple solution for this is to add allocation flags to ring_buffer_read_prepare() so kdb can call it without triggering the allocation error. This patch does that. Note that in the original email thread about this, it was suggested that perhaps the solution for kdb was to either preallocate the buffer ahead of time or create our own iterator. I'm hoping that this alternative of adding allocation flags to ring_buffer_read_prepare() can be considered since it means I don't need to duplicate more of the core trace code into "trace_kdb.c" (for either creating my own iterator or re-preparing a ring allocator whose memory was already allocated). NOTE: another option for kdb is to actually figure out how to make it reuse the existing ftrace_dump() function and totally eliminate the duplication. This sounds very appealing and actually works (the "sr z" command can be seen to properly dump the ftrace buffer). The downside here is that ftrace_dump() fully consumes the trace buffer. Unless that is changed I'd rather not use it because it means "ftdump | grep xyz" won't be very useful to search the ftrace buffer since it will throw away the whole trace on the first grep. A future patch to dump only the last few lines of the buffer will also be hard to implement. [1] https://lkml.kernel.org/r/20161117191605.GA21459@google.com Link: http://lkml.kernel.org/r/20190308193205.213659-1-dianders@chromium.org Reported-by: Brian Norris Signed-off-by: Douglas Anderson Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Sasha Levin

libceph: wait for latest osdmap in ceph_monc_blacklist_add()

2019-03-27T05:13:02+00:00

commit bb229bbb3bf63d23128e851a1f3b85c083178fa1 upstream. Because map updates are distributed lazily, an OSD may not know about the new blacklist for quite some time after "osd blacklist add" command is completed. This makes it possible for a blacklisted but still alive client to overwrite a post-blacklist update, resulting in data corruption. Waiting for latest osdmap in ceph_monc_blacklist_add() and thus using the post-blacklist epoch for all post-blacklist requests ensures that all such requests "wait" for the blacklist to come into force on their respective OSDs. Cc: stable@vger.kernel.org Fixes: 6305a3b41515 ("libceph: support for blacklisting clients") Signed-off-by: Ilya Dryomov Reviewed-by: Jason Dillaman Signed-off-by: Greg Kroah-Hartman

dm: fix to_sector() for 32bit

2019-03-23T12:19:52+00:00

commit 0bdb50c531f7377a9da80d3ce2d61f389c84cb30 upstream. A dm-raid array with devices larger than 4GB won't assemble on a 32 bit host since _check_data_dev_sectors() was added in 4.16. This is because to_sector() treats its argument as an "unsigned long" which is 32bits (4GB) on a 32bit host. Using "unsigned long long" is more correct. Kernels as early as 4.2 can have other problems due to to_sector() being used on the size of a device. Fixes: 0cf4503174c1 ("dm raid: add support for the MD RAID0 personality") cc: stable@vger.kernel.org (v4.2+) Reported-and-tested-by: Guillaume Perréal Signed-off-by: NeilBrown Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

device property: Fix the length used in PROPERTY_ENTRY_STRING()

2019-03-23T12:19:50+00:00

commit 2b6e492467c78183bb629bb0a100ea3509b615a5 upstream. With string type property entries we need to use sizeof(const char *) instead of the number of characters as the length of the entry. If the string was shorter then sizeof(const char *), attempts to read it would have failed with -EOVERFLOW. The problem has been hidden because all build-in string properties have had a string longer then 8 characters until now. Fixes: a85f42047533 ("device property: helper macros for property entry creation") Cc: 4.5+ # 4.5+ Signed-off-by: Heikki Krogerus Reviewed-by: Andy Shevchenko Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

splice: don't merge into linked buffers

2019-03-23T12:19:47+00:00

commit a0ce2f0aa6ad97c3d4927bf2ca54bcebdf062d55 upstream. Before this patch, it was possible for two pipes to affect each other after data had been transferred between them with tee(): ============ $ cat tee_test.c int main(void) { int pipe_a[2]; if (pipe(pipe_a)) err(1, "pipe"); int pipe_b[2]; if (pipe(pipe_b)) err(1, "pipe"); if (write(pipe_a[1], "abcd", 4) != 4) err(1, "write"); if (tee(pipe_a[0], pipe_b[1], 2, 0) != 2) err(1, "tee"); if (write(pipe_b[1], "xx", 2) != 2) err(1, "write"); char buf[5]; if (read(pipe_a[0], buf, 4) != 4) err(1, "read"); buf[4] = 0; printf("got back: '%s'\n", buf); } $ gcc -o tee_test tee_test.c $ ./tee_test got back: 'abxx' $ ============ As suggested by Al Viro, fix it by creating a separate type for non-mergeable pipe buffers, then changing the types of buffers in splice_pipe_to_pipe() and link_pipe(). Cc: Fixes: 7c77f0b3f920 ("splice: implement pipe to pipe splicing") Fixes: 70524490ee2e ("[PATCH] splice: add support for sys_tee()") Suggested-by: Al Viro Signed-off-by: Jann Horn Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman

of: Support const and non-const use for to_of_node()

2019-03-19T12:14:11+00:00

commit d20dc1493db438fbbfb7733adc82f472dd8a0789 upstream. Turn to_of_node() into a macro in order to support both const and non-const use. Additionally make the fwnode argument to is_of_node() const as well. Signed-off-by: Sakari Ailus Reviewed-by: Kieran Bingham Signed-off-by: Rob Herring Cc: Nathan Chancellor Signed-off-by: Greg Kroah-Hartman

cpufreq: Use struct kobj_attribute instead of struct global_attr

2019-03-13T21:04:51+00:00

commit 625c85a62cb7d3c79f6e16de3cfa972033658250 upstream. The cpufreq_global_kobject is created using kobject_create_and_add() helper, which assigns the kobj_type as dynamic_kobj_ktype and show/store routines are set to kobj_attr_show() and kobj_attr_store(). These routines pass struct kobj_attribute as an argument to the show/store callbacks. But all the cpufreq files created using the cpufreq_global_kobject expect the argument to be of type struct attribute. Things work fine currently as no one accesses the "attr" argument. We may not see issues even if the argument is used, as struct kobj_attribute has struct attribute as its first element and so they will both get same address. But this is logically incorrect and we should rather use struct kobj_attribute instead of struct global_attr in the cpufreq core and drivers and the show/store callbacks should take struct kobj_attribute as argument instead. This bug is caught using CFI CLANG builds in android kernel which catches mismatch in function prototypes for such callbacks. Reported-by: Donghee Han Reported-by: Sangkyu Kim Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

sched/sysctl: Fix attributes of some extern declarations

2019-02-27T09:07:03+00:00

commit a9903f04e0a4ea522d959c2f287cdf0ab029e324 upstream. The definition of sysctl_sched_migration_cost, sysctl_sched_nr_migrate and sysctl_sched_time_avg includes the attribute const_debug. This attribute is not part of the extern declaration of these variables in include/linux/sched/sysctl.h, while it is in kernel/sched/sched.h, and as a result Clang generates warnings like this: kernel/sched/sched.h:1618:33: warning: section attribute is specified on redeclared variable [-Wsection] extern const_debug unsigned int sysctl_sched_time_avg; ^ ./include/linux/sched/sysctl.h:42:21: note: previous declaration is here extern unsigned int sysctl_sched_time_avg; The header only declares the variables when CONFIG_SCHED_DEBUG is defined, therefore it is not necessary to duplicate the definition of const_debug. Instead we can use the attribute __read_mostly, which is the expansion of const_debug when CONFIG_SCHED_DEBUG=y is set. Signed-off-by: Matthias Kaehlcke Reviewed-by: Nick Desaulniers Cc: Douglas Anderson Cc: Guenter Roeck Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Shile Zhang Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20171030180816.170850-1-mka@chromium.org Signed-off-by: Ingo Molnar [nc: Backport to 4.9] Signed-off-by: Nathan Chancellor Signed-off-by: Greg Kroah-Hartman