summaryrefslogtreecommitdiff
path: root/kernel
AgeCommit message (Collapse)Author
2018-07-02posix-timers: Make forward callback return s64Thomas Gleixner
The posix timer ti_overrun handling is broken because the forwarding functions can return a huge number of overruns which does not fit in an int. As a consequence timer_getoverrun(2) and siginfo::si_overrun can turn into random number generators. As a first step to address that let the timer_forward() callbacks return the full 64 bit value. Cast it to (int) temporarily until k_itimer::ti_overrun is converted to 64bit and the conversion to user space visible values is sanitized. Reported-by: Team OWL337 <icytxw@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Link: https://lkml.kernel.org/r/20180626132704.922098090@linutronix.de
2018-07-02cpu/hotplug: Boot HT siblings at least onceThomas Gleixner
Due to the way Machine Check Exceptions work on X86 hyperthreads it's required to boot up _all_ logical cores at least once in order to set the CR4.MCE bit. So instead of ignoring the sibling threads right away, let them boot up once so they can configure themselves. After they came out of the initial boot stage check whether its a "secondary" sibling and cancel the operation which puts the CPU back into offline state. Reported-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tony Luck <tony.luck@intel.com>
2018-07-01Merge tag 'dma-mapping-4.18-2' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds
Pull dma mapping fixlet from Christoph Hellwig: "Add a missing export required by riscv and unicore" * tag 'dma-mapping-4.18-2' of git://git.infradead.org/users/hch/dma-mapping: swiotlb: export swiotlb_dma_ops
2018-07-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf 2018-07-01 The following pull-request contains BPF updates for your *net* tree. The main changes are: 1) A bpf_fib_lookup() helper fix to change the API before freeze to return an encoding of the FIB lookup result and return the nexthop device index in the params struct (instead of device index as return code that we had before), from David. 2) Various BPF JIT fixes to address syzkaller fallout, that is, do not reject progs when set_memory_*() fails since it could still be RO. Also arm32 JIT was not using bpf_jit_binary_lock_ro() API which was an issue, and a memory leak in s390 JIT found during review, from Daniel. 3) Multiple fixes for sockmap/hash to address most of the syzkaller triggered bugs. Usage with IPv6 was crashing, a GPF in bpf_tcp_close(), a missing sock_map_release() routine to hook up to callbacks, and a fix for an omitted bucket lock in sock_close(), from John. 4) Two bpftool fixes to remove duplicated error message on program load, and another one to close the libbpf object after program load. One additional fix for nfp driver's BPF offload to avoid stopping offload completely if replace of program failed, from Jakub. 5) Couple of BPF selftest fixes that bail out in some of the test scripts if the user does not have the right privileges, from Jeffrin. 6) Fixes in test_bpf for s390 when CONFIG_BPF_JIT_ALWAYS_ON is set where we need to set the flag that some of the test cases are expected to fail, from Kleber. 7) Fix to detangle BPF_LIRC_MODE2 dependency from CONFIG_CGROUP_BPF since it has no relation to it and lirc2 users often have configs without cgroups enabled and thus would not be able to use it, from Sean. 8) Fix a selftest failure in sockmap by removing a useless setrlimit() call that would set a too low limit where at the same time we are already including bpf_rlimit.h that does the job, from Yonghong. 9) Fix BPF selftest config with missing missing NET_SCHED, from Anders. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-01bpf: sockhash, add release routineJohn Fastabend
Add map_release_uref pointer to hashmap ops. This was dropped when original sockhash code was ported into bpf-next before initial commit. Fixes: 81110384441a ("bpf: sockmap, add hash map support") Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-01bpf: sockhash fix omitted bucket lock in sock_closeJohn Fastabend
First the sk_callback_lock() was being used to protect both the sock callback hooks and the psock->maps list. This got overly convoluted after the addition of sockhash (in sockmap it made some sense because masp and callbacks were tightly coupled) so lets split out a specific lock for maps and only use the callback lock for its intended purpose. This fixes a couple cases where we missed using maps lock when it was in fact needed. Also this makes it easier to follow the code because now we can put the locking closer to the actual code its serializing. Next, in sock_hash_delete_elem() the pattern was as follows, sock_hash_delete_elem() [...] spin_lock(bucket_lock) l = lookup_elem_raw() if (l) hlist_del_rcu() write_lock(sk_callback_lock) .... destroy psock ... write_unlock(sk_callback_lock) spin_unlock(bucket_lock) The ordering is necessary because we only know the {p}sock after dereferencing the hash table which we can't do unless we have the bucket lock held. Once we have the bucket lock and the psock element it is deleted from the hashmap to ensure any other path doing a lookup will fail. Finally, the refcnt is decremented and if zero the psock is destroyed. In parallel with the above (or free'ing the map) a tcp close event may trigger tcp_close(). Which at the moment omits the bucket lock altogether (oops!) where the flow looks like this, bpf_tcp_close() [...] write_lock(sk_callback_lock) for each psock->maps // list of maps this sock is part of hlist_del_rcu(ref_hash_node); .... destroy psock ... write_unlock(sk_callback_lock) Obviously, and demonstrated by syzbot, this is broken because we can have multiple threads deleting entries via hlist_del_rcu(). To fix this we might be tempted to wrap the hlist operation in a bucket lock but that would create a lock inversion problem. In summary to follow locking rules the psocks maps list needs the sk_callback_lock (after this patch maps_lock) but we need the bucket lock to do the hlist_del_rcu. To resolve the lock inversion problem pop the head of the maps list repeatedly and remove the reference until no more are left. If a delete happens in parallel from the BPF API that is OK as well because it will do a similar action, lookup the lock in the map/hash, delete it from the map/hash, and dec the refcnt. We check for this case before doing a destroy on the psock to ensure we don't have two threads tearing down a psock. The new logic is as follows, bpf_tcp_close() e = psock_map_pop(psock->maps) // done with map lock bucket_lock() // lock hash list bucket l = lookup_elem_raw(head, hash, key, key_size); if (l) { //only get here if elmnt was not already removed hlist_del_rcu() ... destroy psock... } bucket_unlock() And finally for all the above to work add missing locking around map operations per above. Then add RCU annotations and use rcu_dereference/rcu_assign_pointer to manage values relying on RCU so that the object is not free'd from sock_hash_free() while it is being referenced in bpf_tcp_close(). Reported-by: syzbot+0ce137753c78f7b6acc1@syzkaller.appspotmail.com Fixes: 81110384441a ("bpf: sockmap, add hash map support") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-01bpf: sockmap, fix smap_list_map_remove when psock is in many mapsJohn Fastabend
If a hashmap is free'd with open socks it removes the reference to the hash entry from the psock. If that is the last reference to the psock then it will also be free'd by the reference counting logic. However the current logic that removes the hash reference from the list of references is broken. In smap_list_remove() we first check if the sockmap entry matches and then check if the hashmap entry matches. But, the sockmap entry sill always match because its NULL in this case which causes the first entry to be removed from the list. If this is always the "right" entry (because the user adds/removes entries in order) then everything is OK but otherwise a subsequent bpf_tcp_close() may reference a free'd object. To fix this create two list handlers one for sockmap and one for sockhash. Reported-by: syzbot+0ce137753c78f7b6acc1@syzkaller.appspotmail.com Fixes: 81110384441a ("bpf: sockmap, add hash map support") Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-01bpf: sockmap, fix crash when ipv6 sock is addedJohn Fastabend
This fixes a crash where we assign tcp_prot to IPv6 sockets instead of tcpv6_prot. Previously we overwrote the sk->prot field with tcp_prot even in the AF_INET6 case. This patch ensures the correct tcp_prot and tcpv6_prot are used. Tested with 'netserver -6' and 'netperf -H [IPv6]' as well as 'netperf -H [IPv4]'. The ESTABLISHED check resolves the previously crashing case here. Fixes: 174a79ff9515 ("bpf: sockmap with sk redirect support") Reported-by: syzbot+5c063698bdbfac19f363@syzkaller.appspotmail.com Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-06-29bpf: undo prog rejection on read-only lock failureDaniel Borkmann
Partially undo commit 9facc336876f ("bpf: reject any prog that failed read-only lock") since it caused a regression, that is, syzkaller was able to manage to cause a panic via fault injection deep in set_memory_ro() path by letting an allocation fail: In x86's __change_page_attr_set_clr() it was able to change the attributes of the primary mapping but not in the alias mapping via cpa_process_alias(), so the second, inner call to the __change_page_attr() via __change_page_attr_set_clr() had to split a larger page and failed in the alloc_pages() with the artifically triggered allocation error which is then propagated down to the call site. Thus, for set_memory_ro() this means that it returned with an error, but from debugging a probe_kernel_write() revealed EFAULT on that memory since the primary mapping succeeded to get changed. Therefore the subsequent hdr->locked = 0 reset triggered the panic as it was performed on read-only memory, so call-site assumptions were infact wrong to assume that it would either succeed /or/ not succeed at all since there's no such rollback in set_memory_*() calls from partial change of mappings, in other words, we're left in a state that is "half done". A later undo via set_memory_rw() is succeeding though due to matching permissions on that part (aka due to the try_preserve_large_page() succeeding). While reproducing locally with explicitly triggering this error, the initial splitting only happens on rare occasions and in real world it would additionally need oom conditions, but that said, it could partially fail. Therefore, it is definitely wrong to bail out on set_memory_ro() error and reject the program with the set_memory_*() semantics we have today. Shouldn't have gone the extra mile since no other user in tree today infact checks for any set_memory_*() errors, e.g. neither module_enable_ro() / module_disable_ro() for module RO/NX handling which is mostly default these days nor kprobes core with alloc_insn_page() / free_insn_page() as examples that could be invoked long after bootup and original 314beb9bcabf ("x86: bpf_jit_comp: secure bpf jit against spraying attacks") did neither when it got first introduced to BPF so "improving" with bailing out was clearly not right when set_memory_*() cannot handle it today. Kees suggested that if set_memory_*() can fail, we should annotate it with __must_check, and all callers need to deal with it gracefully given those set_memory_*() markings aren't "advisory", but they're expected to actually do what they say. This might be an option worth to move forward in future but would at the same time require that set_memory_*() calls from supporting archs are guaranteed to be "atomic" in that they provide rollback if part of the range fails, once that happened, the transition from RW -> RO could be made more robust that way, while subsequent RO -> RW transition /must/ continue guaranteeing to always succeed the undo part. Reported-by: syzbot+a4eb8c7766952a1ca872@syzkaller.appspotmail.com Reported-by: syzbot+d866d1925855328eac3b@syzkaller.appspotmail.com Fixes: 9facc336876f ("bpf: reject any prog that failed read-only lock") Cc: Laura Abbott <labbott@redhat.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-06-28audit: simplify audit_enabled check in audit_watch_log_rule_change()Richard Guy Briggs
Check the audit_enabled flag and bail immediately. This does not change the functionality, but brings the code format in line with similar checks in audit_tree_log_remove_rule(), audit_mark_log_rule_change(), and elsewhere in the audit code. See: https://github.com/linux-audit/audit-kernel/issues/50 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> [PM: tweaked subject line] Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-06-28audit: check audit_enabled in audit_tree_log_remove_rule()Richard Guy Briggs
Respect the audit_enabled flag when printing tree rule config change records. See: https://github.com/linux-audit/audit-kernel/issues/50 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> [PM: tweak the subject line] Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-06-28printk: Export is_console_lockedHans de Goede
This is a preparation patch for adding a number of WARN_CONSOLE_UNLOCKED() calls to the fbcon code, which may be built as a module (event though usually it is not). Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2018-06-28swiotlb: export swiotlb_dma_opsChristoph Hellwig
For architectures that do not use per-device dma ops we need to export the dma_map_ops structure returned from get_arch_dma_ops(). Fixes: 10314e09 ("riscv: add swiotlb support") Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Andreas Schwab <schwab@suse.de>
2018-06-27printk: Remove unnecessary kmalloc() from syslog during clearNamit Gupta
When the request is only for clearing logs, there is no need for allocation/deallocation. Only the indexes need to be reset and returned. Rest of the patch is mostly made up of changes because of indention. Link: http://lkml.kernel.org/r/20180620135951epcas5p3bd2a8f25ec689ca333bce861b527dba2~54wyKcT0_3155531555epcas5p3y@epcas5p3.samsung.com Cc: linux-kernel@vger.kernel.org Cc: pankaj.m@samsung.com Cc: a.sahrawat@samsung.com Signed-off-by: Namit Gupta <gupta.namit@samsung.com> Signed-off-by: Himanshu Maithani <himanshu.m@samsung.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-06-27printk: make sure to print log on console.Maninder Singh
This patch make sure printing of log on console if loglevel at time of storing log is less than current console loglevel. @why In SMP printk can work asynchronously, logs can be missed on console because it checks current log level at time of console_unlock, not at time of storing logs. func() { .... .... console_verbose(); // user wants to have all the logs on console. pr_alert(); dump_backtrace(); //prints with default loglevel. ... console_silent(); // stop all logs from printing on console. } Now if console_lock was owned by another process, the messages might be handled after the consoles were silenced. Reused flag LOG_NOCONS as its usage is gone long back by the commit 5c2992ee7fd8a29d0412 ("printk: remove console flushing special cases for partial buffered lines"). Note that there are still some corner cases where this patch is not enough. For example, when the messages are flushed later from printk_safe buffers or when there are races between console_verbose() and console_silent() callers. Link: http://lkml.kernel.org/r/20180601090029epcas5p3cc93d4bfbebb3199f0a2684058da7e26~z-a_jkmrI2993329933epcas5p3q@epcas5p3.samsung.com Cc: linux-kernel@vger.kernel.org Cc: a.sahrawat@samsung.com Cc: pankaj.m@samsung.com Cc: v.narang@samsung.com Cc: <maninder1.s@samsung.com> Signed-off-by: Vaneet Narang <v.narang@samsung.com> Signed-off-by: Maninder Singh <maninder1.s@samsung.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-06-27fsnotify: let connector point to an abstract objectAmir Goldstein
Make the code to attach/detach a connector to object more generic by letting the fsnotify connector point to an abstract fsnotify_connp_t. Code that needs to dereference an inode or mount object now uses the helpers fsnotify_conn_{inode,mount}. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-06-27perf/core: Move inline keyword at the beginning of declarationMathieu Malaterre
Fix non-fatal warning triggered during compilation with W=1: kernel/events/core.c:6106:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration] static void __always_inline ^~~~~~ Signed-off-by: Mathieu Malaterre <malat@debian.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180626202301.20270-1-malat@debian.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-26rcu: Exclude near-simultaneous RCU CPU stall warningsPaul E. McKenney
There is a two-jiffy delay between the time that a CPU will self-report an RCU CPU stall warning and the time that some other CPU will report a warning on behalf of the first CPU. This has worked well in the past, but on busy systems, it is possible for the two warnings to overlap, which makes interpreting them extremely difficult. This commit therefore uses a cmpxchg-based timing decision that allows only one report in a given one-minute period (assuming default stall-warning Kconfig parameters). This approach will of course fail if you are seeing minute-long vCPU preemption, but in that case the overlapping RCU CPU stall warnings are the least of your worries. Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-26rcu: Use the proper lockdep annotation in dump_blkd_tasks()Boqun Feng
Sparse reported this: | kernel/rcu/tree_plugin.h:814:9: warning: incorrect type in argument 1 (different modifiers) | kernel/rcu/tree_plugin.h:814:9: expected struct lockdep_map const *lock | kernel/rcu/tree_plugin.h:814:9: got struct lockdep_map [noderef] *<noident> This is caused by using vanilla lockdep annotations on rcu_node::lock, and that requires accessing ->lock of rcu_node directly. However we need to keep rcu_node::lock __private to avoid breaking its extra ordering guarantee. And we have a dedicated lockdep annotation for rcu_node::lock, so use it. Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-26rcu: Add debugging info to assertionPaul E. McKenney
The WARN_ON_ONCE(rcu_preempt_blocked_readers_cgp()) in rcu_gp_cleanup() triggers (inexplicably, of course) every so often. This commit therefore extracts more information. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-26bpf: fix attach type BPF_LIRC_MODE2 dependency wrt CONFIG_CGROUP_BPFSean Young
If the kernel is compiled with CONFIG_CGROUP_BPF not enabled, it is not possible to attach, detach or query IR BPF programs to /dev/lircN devices, making them impossible to use. For embedded devices, it should be possible to use IR decoding without cgroups or CONFIG_CGROUP_BPF enabled. This change requires some refactoring, since bpf_prog_{attach,detach,query} functions are now always compiled, but their code paths for cgroups need moving out. Rather than a #ifdef CONFIG_CGROUP_BPF in kernel/bpf/syscall.c, moving them to kernel/bpf/cgroup.c and kernel/bpf/sockmap.c does not require #ifdefs since that is already conditionally compiled. Fixes: f4364dcfc86d ("media: rc: introduce BPF_PROG_LIRC_MODE2") Signed-off-by: Sean Young <sean@mess.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-06-26perf/hw_breakpoint: Clean up and consolidate modify_user_hw_breakpoint_check()Frederic Weisbecker
Remove the dance around old and new attributes. Just don't modify the previous breakpoint at all until we have verified everything. Original-patch-by: Andy Lutomirski <luto@kernel.org> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Joel Fernandes <joel.opensrc@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/1529981939-8231-13-git-send-email-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-26perf/hw_breakpoint: Pass new breakpoint type to modify_breakpoint_slot()Frederic Weisbecker
We soon won't be able to rely on bp->attr anymore to get the new type of the modifying breakpoint because the new attributes are going to be copied only once we successfully modified the breakpoint slot. This will fix the current misdesigned layout where the new attr are copied to the modifying breakpoint before we actually know if the modification will be validated. In order to prepare for that, allow modify_breakpoint_slot() to take the new breakpoint type. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Joel Fernandes <joel.opensrc@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/1529981939-8231-12-git-send-email-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-26perf/hw_breakpoint: Remove default hw_breakpoint_arch_parse()Frederic Weisbecker
All architectures have implemented it, we can now remove the poor weak version. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Joel Fernandes <joel.opensrc@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/1529981939-8231-11-git-send-email-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-26perf/hw_breakpoint: Pass arch breakpoint struct to ↵Frederic Weisbecker
arch_check_bp_in_kernelspace() We can't pass the breakpoint directly on arch_check_bp_in_kernelspace() anymore because its architecture internal datas (struct arch_hw_breakpoint) are not yet filled by the time we call the function, and most implementation need this backend to be up to date. So arrange the function to take the probing struct instead. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Joel Fernandes <joel.opensrc@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/1529981939-8231-3-git-send-email-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-26perf/hw_breakpoint: Split attribute parse and commitFrederic Weisbecker
arch_validate_hwbkpt_settings() mixes up attribute check and commit into a single code entity. Therefore the validation may return an error due to incorrect atributes while still leaving halfway modified architecture breakpoint data. This is harmless when we deal with a new breakpoint but it becomes a problem when we modify an existing breakpoint. Split attribute parse and commit to fix that. The architecture is passed a "struct arch_hw_breakpoint" to fill on top of the new attr and the core takes care about copying the backend data once it's fully validated. The architectures then need to implement the new API. Original-patch-by: Andy Lutomirski <luto@kernel.org> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Joel Fernandes <joel.opensrc@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/1529981939-8231-2-git-send-email-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-26Merge branch 'linus' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-25torture: Keep old-school dmesg formatPaul E. McKenney
This commit adds "#define pr_fmt(fmt) fmt" to the torture-test files in order to keep the current dmesg format. Once Joe's commits have hit mainline, these definitions will be changed in order to automatically generate the dmesg line prefix that the scripts expect. This will have the beneficial side-effect of allowing printk() formats to be used more widely and of shortening some pr_*() lines. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Joe Perches <joe@perches.com>
2018-06-25torture: Make online/offline messages appear only for verbose=2Paul E. McKenney
Some bugs reproduce quickly only at high CPU-hotplug rates, so the rcutorture TREE03 scenario now has only 200 milliseconds spacing between CPU-hotplug operations. At this rate, the torture-test pair of console messages per operation becomes a bit voluminous. This commit therefore converts the torture-test set of "verbose" kernel-boot arguments from bool to int, and prints the extra console messages only when verbose=2. The default is still verbose=1. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-25srcu: Add address of first callback to rcutorture outputPaul E. McKenney
This commit adds the address of the first callback to the per-CPU rcutorture output in order to allow lost wakeups to be more efficiently tracked down. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-25srcu: Document that srcu_funnel_gp_start() implies srcu_funnel_exp_start()Paul E. McKenney
This commit updates the header comment of srcu_funnel_gp_start() to document the fact that srcu_funnel_gp_start() does the work of srcu_funnel_exp_start(), in some cases by invoking it directly. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-25srcu: Fix typos in __call_srcu() header commentPaul E. McKenney
This commit simply changes some copy-pasta call_rcu() instances to the correct call_srcu(). Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-25rcu: Make expedited grace period use direct call on last leafPaul E. McKenney
During expedited grace-period initialization, a work item is scheduled for each leaf rcu_node structure. However, that initialization code is itself (normally) executing from a workqueue, so one of the leaf rcu_node structures could just as well be handled by that pre-existing workqueue, and with less overhead. This commit therefore uses a shiny new rcu_is_leaf_node() macro to execute the last leaf rcu_node structure's initialization directly from the pre-existing workqueue. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-25module: replace VMLINUX_SYMBOL_STR() with __stringify() or string literalMasahiro Yamada
With the special case handling for Blackfin and Metag was removed by commit 94e58e0ac312 ("export.h: remove code for prefixing symbols with underscore"), VMLINUX_SYMBOL_STR() is now equivalent to __stringify(). Replace the remaining usages to prepare for the entire removal of VMLINUX_SYMBOL_STR(). Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-06-25module: print sensible error codeJason A. Donenfeld
Printing "err 0" to the user in the warning message is not particularly useful, especially when this gets transformed into a -ENOENT for the remainder of the call chain. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-06-24dma-noncoherent: add a arch_sync_dma_for_cpu_all hookChristoph Hellwig
The MIPS bmips platform needs a global flush when transferring ownership back to the CPU. Add a hook for that to the dma-noncoherent implementation. Signed-off-by: Christoph Hellwig <hch@lst.de> Patchwork: https://patchwork.linux-mips.org/patch/19549/ Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: David Daney <david.daney@cavium.com> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: Tom Bogendoerfer <tsbogend@alpha.franken.de> Cc: Huacai Chen <chenhc@lemote.com> Cc: iommu@lists.linux-foundation.org Cc: linux-mips@linux-mips.org
2018-06-24time: Change types to new y2038 safe __kernel_itimerspecDeepa Dinamani
timer_set/gettime and timerfd_set/get apis use struct itimerspec at the user interface layer. struct itimerspec is not y2038-safe. Change these interfaces to use y2038-safe struct __kernel_itimerspec instead. This will help define new syscalls when 32bit architectures select CONFIG_64BIT_TIME. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: viro@zeniv.linux.org.uk Cc: linux-fsdevel@vger.kernel.org Cc: linux-api@vger.kernel.org Cc: y2038@lists.linaro.org Link: https://lkml.kernel.org/r/20180617051144.29756-4-deepa.kernel@gmail.com
2018-06-24time: Enable get/put_compat_itimerspec64 alwaysDeepa Dinamani
This will aid in enabling the compat syscalls on 32-bit architectures later on. Also move compat_itimerspec and related defines to compat_time.h. The compat_time.h file will eventually be deleted. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: viro@zeniv.linux.org.uk Cc: linux-fsdevel@vger.kernel.org Cc: linux-api@vger.kernel.org Cc: y2038@lists.linaro.org Link: https://lkml.kernel.org/r/20180617051144.29756-3-deepa.kernel@gmail.com
2018-06-24time: Introduce struct __kernel_itimerspecDeepa Dinamani
struct itimerspec is not y2038-safe. Introduce a new struct __kernel_itimerspec based on the kernel internal y2038-safe struct itimerspec64. The definition of struct __kernel_itimerspec includes two struct __kernel_timespec. Since struct __kernel_timespec has the same representation in native and compat modes, so does struct __kernel_itimerspec. This helps have a common entry point for syscalls using struct __kernel_itimerspec. New y2038-safe syscalls will use this new type. Since most of the new syscalls are just an update to the native syscalls with the type update, place the new definition under CONFIG_64BIT_TIME. This helps architectures that do not support the above config to keep using the old definition of struct itimerspec. Also change the get/put_itimerspec64 to use struct__kernel_itimerspec. This will help 32 bit architectures to use the new syscalls when architectures select CONFIG_64BIT_TIME. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: viro@zeniv.linux.org.uk Cc: linux-fsdevel@vger.kernel.org Cc: linux-api@vger.kernel.org Cc: y2038@lists.linaro.org Link: https://lkml.kernel.org/r/20180617051144.29756-2-deepa.kernel@gmail.com
2018-06-24Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "A pile of perf updates: Kernel side: - Remove an incorrect warning in uprobe_init_insn() when insn_get_length() fails. The error return code is handled at the call site. - Move the inline keyword to the right place in the perf ringbuffer code to address a W=1 build warning. Tooling: perf stat: - Fix metric column header display alignment - Improve error messages for default attributes, providing better output for error in command line. - Add --interval-clear option, to provide a 'watch' like printing perf script: - Show hw-cache events too perf c2c: - Fix data dependency problem in layout of 'struct c2c_hist_entry' Core: - Do not blindly assume that 'struct perf_evsel' can be obtained via a straight forward container_of() as there are call sites which hand in a plain 'struct hist' which is not part of a container. - Fix error index in the PMU event parser, so that error messages can point to the problematic token" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Move the inline keyword at the beginning of the function declaration uprobes/x86: Remove incorrect WARN_ON() in uprobe_init_insn() perf script: Show hw-cache events perf c2c: Keep struct hist_entry at the end of struct c2c_hist_entry perf stat: Add event parsing error handling to add_default_attributes perf stat: Allow to specify specific metric column len perf stat: Fix metric column header display alignment perf stat: Use only color_fprintf call in print_metric_only perf stat: Add --interval-clear option perf tools: Fix error index for pmu event parser perf hists: Reimplement hists__has_callchains() perf hists browser gtk: Use hist_entry__has_callchains() perf hists: Make hist_entry__has_callchains() work with 'perf c2c' perf hists: Save the callchain_size in struct hist_entry
2018-06-24Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull rseq fixes from Thomas Gleixer: "A pile of rseq related fixups: - Prevent infinite recursion when delivering SIGSEGV - Remove the abort of rseq critical section on fork() as syscalls inside rseq critical sections are explicitely forbidden. So no point in doing the abort on the child. - Align the rseq structure on 32 bytes in the ARM selftest code. - Fix file permissions of the test script" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rseq: Avoid infinite recursion when delivering SIGSEGV rseq/cleanup: Do not abort rseq c.s. in child on fork() rseq/selftests/arm: Align 'struct rseq_cs' on 32 bytes rseq/selftests: Make run_param_test.sh executable
2018-06-24genirq: Synchronize only with single thread on free_irq()Lukas Wunner
When pciehp is converted to threaded IRQ handling, removal of unplugged devices below a PCIe hotplug port happens synchronously in the IRQ thread. Removal of devices typically entails a call to free_irq() by their drivers. If those devices share their IRQ with the hotplug port, __free_irq() deadlocks because it calls synchronize_irq() to wait for all hard IRQ handlers as well as all threads sharing the IRQ to finish. Actually it's sufficient to wait only for the IRQ thread of the removed device, so call synchronize_hardirq() to wait for all hard IRQ handlers to finish, but no longer for any threads. Compensate by rearranging the control flow in irq_wait_for_interrupt() such that the device's thread is allowed to run one last time after kthread_stop() has been called. kthread_stop() blocks until the IRQ thread has completed. On completion the IRQ thread clears its oneshot thread_mask bit. This is safe because __free_irq() holds the request_mutex, thereby preventing __setup_irq() from handing out the same oneshot thread_mask bit to a newly requested action. Stack trace for posterity: INFO: task irq/17-pciehp:94 blocked for more than 120 seconds. schedule+0x28/0x80 synchronize_irq+0x6e/0xa0 __free_irq+0x15a/0x2b0 free_irq+0x33/0x70 pciehp_release_ctrl+0x98/0xb0 pcie_port_remove_service+0x2f/0x40 device_release_driver_internal+0x157/0x220 bus_remove_device+0xe2/0x150 device_del+0x124/0x340 device_unregister+0x16/0x60 remove_iter+0x1a/0x20 device_for_each_child+0x4b/0x90 pcie_port_device_remove+0x1e/0x30 pci_device_remove+0x36/0xb0 device_release_driver_internal+0x157/0x220 pci_stop_bus_device+0x7d/0xa0 pci_stop_bus_device+0x3d/0xa0 pci_stop_and_remove_bus_device+0xe/0x20 pciehp_unconfigure_device+0xb8/0x160 pciehp_disable_slot+0x84/0x130 pciehp_ist+0x158/0x190 irq_thread_fn+0x1b/0x50 irq_thread+0x143/0x1a0 kthread+0x111/0x130 Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: linux-pci@vger.kernel.org Link: https://lkml.kernel.org/r/d72b41309f077c8d3bee6cc08ad3662d50b5d22a.1529828292.git.lukas@wunner.de
2018-06-24genirq: Update code comments wrt recycled thread_maskLukas Wunner
Previously a race existed between __free_irq() and __setup_irq() wherein the thread_mask of a just removed action could be handed out to a newly added action and the freed irq thread would then tread on the oneshot mask bit of the newly added irq thread in irq_finalize_oneshot(): time | __free_irq() | raw_spin_lock_irqsave(&desc->lock, flags); | <remove action from linked list> | raw_spin_unlock_irqrestore(&desc->lock, flags); | | __setup_irq() | raw_spin_lock_irqsave(&desc->lock, flags); | <traverse linked list to determine oneshot mask bit> | raw_spin_unlock_irqrestore(&desc->lock, flags); | | irq_thread() of freed irq (__free_irq() waits in synchronize_irq()) | irq_thread_fn() | irq_finalize_oneshot() | raw_spin_lock_irq(&desc->lock); | desc->threads_oneshot &= ~action->thread_mask; | raw_spin_unlock_irq(&desc->lock); v The race was known at least since 2012 when it was documented in a code comment by commit e04268b0effc ("genirq: Remove paranoid warnons and bogus fixups"). The race itself is harmless as nothing touches any of the potentially freed data after synchronize_irq(). In 2017 the race was close by commit 9114014cf4e6 ("genirq: Add mutex to irq desc to serialize request/free_irq()"), apparently inadvertantly so because the race is neither mentioned in the commit message nor was the code comment updated. Make up for that. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: linux-pci@vger.kernel.org Link: https://lkml.kernel.org/r/32fc25aa35ecef4b2692f57687bb7fc2a57230e2.1529828292.git.lukas@wunner.de
2018-06-24Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Thomas Gleixner: "A set of fixes and updates for the locking code: - Prevent lockdep from updating irq state within its own code and thereby confusing itself. - Buid fix for older GCCs which mistreat anonymous unions - Add a missing lockdep annotation in down_read_non_onwer() which causes up_read_non_owner() to emit a lockdep splat - Remove the custom alpha dec_and_lock() implementation which is incorrect in terms of ordering and use the generic one. The remaining two commits are not strictly fixes. They provide irqsave variants of atomic_dec_and_lock() and refcount_dec_and_lock(). These are required to merge the relevant updates and cleanups into different maintainer trees for 4.19, so routing them into mainline without actual users is the sanest approach. They should have been in -rc1, but last weekend I took the liberty to just avoid computers in order to regain some mental sanity" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/qspinlock: Fix build for anonymous union in older GCC compilers locking/lockdep: Do not record IRQ state within lockdep code locking/rwsem: Fix up_read_non_owner() warning with DEBUG_RWSEMS locking/refcounts: Implement refcount_dec_and_lock_irqsave() atomic: Add irqsave variant of atomic_dec_and_lock() alpha: Remove custom dec_and_lock() implementation
2018-06-24Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "A small set of fixes for time(r) related issues: - Fix a long standing conversion issue in jiffies_to_msecs() for odd HZ values like 1024 or 1200 which resulted in returning 0 for small jiffies values due to rounding down. - Use the proper CONFIG symbol in the new Y2038 safe compat code for posix-timers. Not yet a visible breakage, but this will immediately trigger when the architecture support for the new interfaces is merged. - Return an error code in the STM32 clocksource driver on failure instead of success. - Remove the redundant and stale irq disabled check in the posix cpu timer code. The check is at the wrong place anyway and lockdep already covers it via the sighand lock locking coverage" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: time: Make sure jiffies_to_msecs() preserves non-zero time periods posix-timers: Fix nanosleep_copyout() for CONFIG_COMPAT_32BIT_TIME clocksource/drivers/stm32: Fix error return code posix-cpu-timers: Remove lockdep_assert_irqs_disabled()
2018-06-24Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: "A set of fixes mostly for the ARM/GIC world: - Fix the MSI affinity handling in the ls-scfg irq chip driver so it updates and uses the effective affinity mask correctly - Prevent binding LPIs to offline CPUs and respect the Cavium erratum which requires that LPIs which belong to an offline NUMA node are not bound to a CPU on a different NUMA node. - Free only the amount of allocated interrupts in the GIC-V2M driver instead of trying to free log2(nrirqs). - Prevent emitting SYNC and VSYNC targetting non existing interrupt collections in the GIC-V3 ITS driver - Ensure that the GIV-V3 interrupt redistributor is correctly reprogrammed on CPU hotplug - Remove a stale unused helper function" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqdesc: Delete irq_desc_get_msi_desc() irqchip/gic-v3-its: Fix reprogramming of redistributors on CPU hotplug irqchip/gic-v3-its: Only emit VSYNC if targetting a valid collection irqchip/gic-v3-its: Only emit SYNC if targetting a valid collection irqchip/gic-v3-its: Don't bind LPI to unavailable NUMA node irqchip/gic-v2m: Fix SPI release on error path irqchip/ls-scfg-msi: Fix MSI affinity handling genirq/debugfs: Add missing IRQCHIP_SUPPORTS_LEVEL_MSI debug
2018-06-24Merge tag 'trace-v4.18-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "This contains a few fixes and a clean up. - a bad merge caused an "endif" to go in the wrong place in scripts/Makefile.build - softirq tracing fix for tracing that corrupts lockdep and causes a false splat - histogram documentation typo fixes - fix a bad memory reference when passing in no filter to the filter code - simplify code by using the swap macro instead of open coding the swap" * tag 'trace-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Fix SKIP_STACK_VALIDATION=1 build due to bad merge with -mrecord-mcount tracing: Fix some errors in histogram documentation tracing: Use swap macro in update_max_tr softirq: Reorder trace_softirqs_on to prevent lockdep splat tracing: Check for no filter when processing event filters
2018-06-22rseq: Avoid infinite recursion when delivering SIGSEGVWill Deacon
When delivering a signal to a task that is using rseq, we call into __rseq_handle_notify_resume() so that the registers pushed in the sigframe are updated to reflect the state of the restartable sequence (for example, ensuring that the signal returns to the abort handler if necessary). However, if the rseq management fails due to an unrecoverable fault when accessing userspace or certain combinations of RSEQ_CS_* flags, then we will attempt to deliver a SIGSEGV. This has the potential for infinite recursion if the rseq code continuously fails on signal delivery. Avoid this problem by using force_sigsegv() instead of force_sig(), which is explicitly designed to reset the SEGV handler to SIG_DFL in the case of a recursive fault. In doing so, remove rseq_signal_deliver() from the internal rseq API and have an optional struct ksignal * parameter to rseq_handle_notify_resume() instead. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: peterz@infradead.org Cc: paulmck@linux.vnet.ibm.com Cc: boqun.feng@gmail.com Link: https://lkml.kernel.org/r/1529664307-983-1-git-send-email-will.deacon@arm.com
2018-06-22time: Make sure jiffies_to_msecs() preserves non-zero time periodsGeert Uytterhoeven
For the common cases where 1000 is a multiple of HZ, or HZ is a multiple of 1000, jiffies_to_msecs() never returns zero when passed a non-zero time period. However, if HZ > 1000 and not an integer multiple of 1000 (e.g. 1024 or 1200, as used on alpha and DECstation), jiffies_to_msecs() may return zero for small non-zero time periods. This may break code that relies on receiving back a non-zero value. jiffies_to_usecs() does not need such a fix: one jiffy can only be less than one µs if HZ > 1000000, and such large values of HZ are already rejected at build time, twice: - include/linux/jiffies.h does #error if HZ >= 12288, - kernel/time/time.c has BUILD_BUG_ON(HZ > USEC_PER_SEC). Broken since forever. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Stephen Boyd <sboyd@kernel.org> Cc: linux-alpha@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180622143357.7495-1-geert@linux-m68k.org
2018-06-22genirq: Speedup show_interrupts()Eric Dumazet
Since commit 425a5072dcd1 ("genirq: Free irq_desc with rcu"), show_interrupts() can be switched to rcu locking, which removes possible contention on sparse_irq_lock. The per_cpu count scan and print can be done without holding desc spinlock. And there is no need to call kstat_irqs_cpu() and abuse irq_to_desc() while holding rcu read lock, since desc and desc->kstat_irqs wont disappear or change. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Eric Dumazet <eric.dumazet@gmail.com> Link: https://lkml.kernel.org/r/20180620150332.163320-1-edumazet@google.com