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2018-03-04Merge 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 from the timer departement: - Add a missing timer wheel clock forward when migrating timers off a unplugged CPU to prevent operating on a stale clock base and missing timer deadlines. - Use the proper shift count to extract data from a register value to prevent evaluating unrelated bits - Make the error return check in the FSL timer driver work correctly. Checking an unsigned variable for less than zero does not really work well. - Clarify the confusing comments in the ARC timer code" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timers: Forward timer base before migrating timers clocksource/drivers/arc_timer: Update some comments clocksource/drivers/mips-gic-timer: Use correct shift count to extract data clocksource/drivers/fsl_ftm_timer: Fix error return checking
2018-03-03Merge branch 'libnvdimm-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm fixes from Dan Williams: "A 4.16 regression fix, three fixes for -stable, and a cleanup fix: - During the merge window support for the new ACPI NVDIMM Platform Capabilities structure disabled support for "deep flush", a force-unit- access like mechanism for persistent memory. Restore that mechanism. - VFIO like RDMA is yet one more memory registration / pinning interface that is incompatible with Filesystem-DAX. Disable long term pins of Filesystem-DAX mappings via VFIO. - The Filesystem-DAX detection to prevent long terms pins mistakenly also disabled Device-DAX pins which are not subject to the same block- map collision concerns. - Similar to the setup path, softlockup warnings can trigger in the shutdown path for large persistent memory namespaces. Teach for_each_device_pfn() to perform cond_resched() in all cases. - Boaz noticed that the might_sleep() in dax_direct_access() is stale as of the v4.15 kernel. These have received a build success notification from the 0day robot, and the longterm pin fixes have appeared in -next. However, I recently rebased the tree to remove some other fixes that need to be reworked after review feedback. * 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: memremap: fix softlockup reports at teardown libnvdimm: re-enable deep flush for pmem devices via fsync() vfio: disable filesystem-dax page pinning dax: fix vma_is_fsdax() helper dax: ->direct_access does not sleep anymore
2018-03-02memremap: fix softlockup reports at teardownDan Williams
The cond_resched() currently in the setup path needs to be duplicated in the teardown path. Rather than require each instance of for_each_device_pfn() to open code the same sequence, embed it in the helper. Link: https://github.com/intel/ixpdimm_sw/issues/11 Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Christoph Hellwig <hch@lst.de> Cc: <stable@vger.kernel.org> Fixes: 71389703839e ("mm, zone_device: Replace {get, put}_zone_device_page()...") Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-03-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk Pull printk fix from Petr Mladek: "Make sure that we wake up userspace loggers. This fixes a race introduced by the console waiter logic during this merge window" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: printk: Wake klogd when passing console_lock owner
2018-02-28timers: Forward timer base before migrating timersLingutla Chandrasekhar
On CPU hotunplug the enqueued timers of the unplugged CPU are migrated to a live CPU. This happens from the control thread which initiated the unplug. If the CPU on which the control thread runs came out from a longer idle period then the base clock of that CPU might be stale because the control thread runs prior to any event which forwards the clock. In such a case the timers from the unplugged CPU are queued on the live CPU based on the stale clock which can cause large delays due to increased granularity of the outer timer wheels which are far away from base:;clock. But there is a worse problem than that. The following sequence of events illustrates it: - CPU0 timer1 is queued expires = 59969 and base->clk = 59131. The timer is queued at wheel level 2, with resulting expiry time = 60032 (due to level granularity). - CPU1 enters idle @60007, with next timer expiry @60020. - CPU0 is hotplugged at @60009 - CPU1 exits idle and runs the control thread which migrates the timers from CPU0 timer1 is now queued in level 0 for immediate handling in the next softirq because the requested expiry time 59969 is before CPU1 base->clk 60007 - CPU1 runs code which forwards the base clock which succeeds because the next expiring timer. which was collected at idle entry time is still set to 60020. So it forwards beyond 60007 and therefore misses to expire the migrated timer1. That timer gets expired when the wheel wraps around again, which takes between 63 and 630ms depending on the HZ setting. Address both problems by invoking forward_timer_base() for the control CPUs timer base. All other places, which might run into a similar problem (mod_timer()/add_timer_on()) already invoke forward_timer_base() to avoid that. [ tglx: Massaged comment and changelog ] Fixes: a683f390b93f ("timers: Forward the wheel clock whenever possible") Co-developed-by: Neeraj Upadhyay <neeraju@codeaurora.org> Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org> Signed-off-by: Lingutla Chandrasekhar <clingutla@codeaurora.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: linux-arm-msm@vger.kernel.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180118115022.6368-1-clingutla@codeaurora.org
2018-02-27printk: Wake klogd when passing console_lock ownerPetr Mladek
wake_klogd is a local variable in console_unlock(). The information is lost when the console_lock owner using the busy wait added by the commit dbdda842fe96f8932 ("printk: Add console owner and waiter logic to load balance console writes"). The following race is possible: CPU0 CPU1 console_unlock() for (;;) /* calling console for last message */ printk() log_store() log_next_seq++; /* see new message */ if (seen_seq != log_next_seq) { wake_klogd = true; seen_seq = log_next_seq; } console_lock_spinning_enable(); if (console_trylock_spinning()) /* spinning */ if (console_lock_spinning_disable_and_check()) { printk_safe_exit_irqrestore(flags); return; console_unlock() if (seen_seq != log_next_seq) { /* already seen */ /* nothing to do */ Result: Nobody would wakeup klogd. One solution would be to make a global variable from wake_klogd. But then we would need to manipulate it under a lock or so. This patch wakes klogd also when console_lock is passed to the spinning waiter. It looks like the right way to go. Also userspace should have a chance to see and store any "flood" of messages. Note that the very late klogd wake up was a historic solution. It made sense on single CPU systems or when sys_syslog() operations were synchronized using the big kernel lock like in v2.1.113. But it is questionable these days. Fixes: dbdda842fe96f8932 ("printk: Add console owner and waiter logic to load balance console writes") Link: http://lkml.kernel.org/r/20180226155734.dzwg3aovqnwtvkoy@pathway.suse.cz Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-kernel@vger.kernel.org Cc: Tejun Heo <tj@kernel.org> Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-26Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "Yet another pile of melted spectrum related changes: - sanitize the array_index_nospec protection mechanism: Remove the overengineered array_index_nospec_mask_check() magic and allow const-qualified types as index to avoid temporary storage in a non-const local variable. - make the microcode loader more robust by properly propagating error codes. Provide information about new feature bits after micro code was updated so administrators can act upon. - optimizations of the entry ASM code which reduce code footprint and make the code simpler and faster. - fix the {pmd,pud}_{set,clear}_flags() implementations to work properly on paravirt kernels by removing the address translation operations. - revert the harmful vmexit_fill_RSB() optimization - use IBRS around firmware calls - teach objtool about retpolines and add annotations for indirect jumps and calls. - explicitly disable jumplabel patching in __init code and handle patching failures properly instead of silently ignoring them. - remove indirect paravirt calls for writing the speculation control MSR as these calls are obviously proving the same attack vector which is tried to be mitigated. - a few small fixes which address build issues with recent compiler and assembler versions" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits) KVM/VMX: Optimize vmx_vcpu_run() and svm_vcpu_run() by marking the RDMSR path as unlikely() KVM/x86: Remove indirect MSR op calls from SPEC_CTRL objtool, retpolines: Integrate objtool with retpoline support more closely x86/entry/64: Simplify ENCODE_FRAME_POINTER extable: Make init_kernel_text() global jump_label: Warn on failed jump_label patching attempt jump_label: Explicitly disable jump labels in __init code x86/entry/64: Open-code switch_to_thread_stack() x86/entry/64: Move ASM_CLAC to interrupt_entry() x86/entry/64: Remove 'interrupt' macro x86/entry/64: Move the switch_to_thread_stack() call to interrupt_entry() x86/entry/64: Move ENTER_IRQ_STACK from interrupt macro to interrupt_entry x86/entry/64: Move PUSH_AND_CLEAR_REGS from interrupt macro to helper function x86/speculation: Move firmware_restrict_branch_speculation_*() from C to CPP objtool: Add module specific retpoline rules objtool: Add retpoline validation objtool: Use existing global variables for options x86/mm/sme, objtool: Annotate indirect call in sme_encrypt_execute() x86/boot, objtool: Annotate indirect jump in secondary_startup_64() x86/paravirt, objtool: Annotate indirect calls ...
2018-02-25Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A small set of fixes: - UAPI data type correction for hyperv - correct the cpu cores field in /proc/cpuinfo on CPU hotplug - return proper error code in the resctrl file system failure path to avoid silent subsequent failures - correct a subtle accounting issue in the new vector allocation code which went unnoticed for a while and caused suspend/resume failures" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/topology: Update the 'cpu cores' field in /proc/cpuinfo correctly across CPU hotplug operations x86/topology: Fix function name in documentation x86/intel_rdt: Fix incorrect returned value when creating rdgroup sub-directory in resctrl file system x86/apic/vector: Handle vector release on CPU unplug correctly genirq/matrix: Handle CPU offlining proper x86/headers/UAPI: Use __u64 instead of u64 in <uapi/asm/hyperv.h>
2018-02-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: 1) Fix TTL offset calculation in mac80211 mesh code, from Peter Oh. 2) Fix races with procfs in ipt_CLUSTERIP, from Cong Wang. 3) Memory leak fix in lpm_trie BPF map code, from Yonghong Song. 4) Need to use GFP_ATOMIC in BPF cpumap allocations, from Jason Wang. 5) Fix potential deadlocks in netfilter getsockopt() code paths, from Paolo Abeni. 6) Netfilter stackpointer size checks really are needed to validate user input, from Florian Westphal. 7) Missing timer init in x_tables, from Paolo Abeni. 8) Don't use WQ_MEM_RECLAIM in mac80211 hwsim, from Johannes Berg. 9) When an ibmvnic device is brought down then back up again, it can be sent queue entries from a previous session, handle this properly instead of crashing. From Thomas Falcon. 10) Fix TCP checksum on LRO buffers in mlx5e, from Gal Pressman. 11) When we are dumping filters in cls_api, the output SKB is empty, and the filter we are dumping is too large for the space in the SKB, we should return -EMSGSIZE like other netlink dump operations do. Otherwise userland has no signal that is needs to increase the size of its read buffer. From Roman Kapl. 12) Several XDP fixes for virtio_net, from Jesper Dangaard Brouer. 13) Module refcount leak in netlink when a dump start fails, from Jason Donenfeld. 14) Handle sub-optimal GSO sizes better in TCP BBR congestion control, from Eric Dumazet. 15) Releasing bpf per-cpu arraymaps can take a long time, add a condtional scheduling point. From Eric Dumazet. 16) Implement retpolines for tail calls in x64 and arm64 bpf JITs. From Daniel Borkmann. 17) Fix page leak in gianfar driver, from Andy Spencer. 18) Missed clearing of estimator scratch buffer, from Eric Dumazet. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits) net_sched: gen_estimator: fix broken estimators based on percpu stats gianfar: simplify FCS handling and fix memory leak ipv6 sit: work around bogus gcc-8 -Wrestrict warning macvlan: fix use-after-free in macvlan_common_newlink() bpf, arm64: fix out of bounds access in tail call bpf, x64: implement retpoline for tail call rxrpc: Fix send in rxrpc_send_data_packet() net: aquantia: Fix error handling in aq_pci_probe() bpf: fix rcu lockdep warning for lpm_trie map_free callback bpf: add schedule points in percpu arrays management regulatory: add NUL to request alpha2 ibmvnic: Fix early release of login buffer net/smc9194: Remove bogus CONFIG_MAC reference net: ipv4: Set addr_type in hash_keys for forwarded case tcp_bbr: better deal with suboptimal GSO smsc75xx: fix smsc75xx_set_features() netlink: put module reference if dump start fails selftests/bpf/test_maps: exit child process without error in ENOMEM case selftests/bpf: update gitignore with test_libbpf_open selftests/bpf: tcpbpf_kern: use in6_* macros from glibc ..
2018-02-23Merge branch 'fixes-v4.16-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem fixes from James Morris: - keys fixes via David Howells: "A collection of fixes for Linux keyrings, mostly thanks to Eric Biggers: - Fix some PKCS#7 verification issues. - Fix handling of unsupported crypto in X.509. - Fix too-large allocation in big_key" - Seccomp updates via Kees Cook: "These are fixes for the get_metadata interface that landed during -rc1. While the new selftest is strictly not a bug fix, I think it's in the same spirit of avoiding bugs" - an IMA build fix from Randy Dunlap * 'fixes-v4.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: integrity/security: fix digsig.c build error with header file KEYS: Use individual pages in big_key for crypto buffers X.509: fix NULL dereference when restricting key with unsupported_sig X.509: fix BUG_ON() when hash algorithm is unsupported PKCS#7: fix direct verification of SignerInfo signature PKCS#7: fix certificate blacklisting PKCS#7: fix certificate chain verification seccomp: add a selftest for get_metadata ptrace, seccomp: tweak get_metadata behavior slightly seccomp, ptrace: switch get_metadata types to arch independent
2018-02-23Merge tag 'drm-fixes-for-v4.16-rc3' of ↵Linus Torvalds
git://people.freedesktop.org/~airlied/linux Pull drm fixes from Dave Airlie: "A bunch of fixes for rc3: Exynos: - fixes for using monotonic timestamps - register definitions - removal of unused file ipu-v3L - minor changes - make some register arrays const+static - fix some leaks meson: - fix for vsync atomic: - fix for memory leak EDID parser: - add quirks for some more non-desktop devices - 6-bit panel fix. drm_mm: - fix a bug in the core drm mm hole handling cirrus: - fix lut loading regression Lastly there is a deadlock fix around runtime suspend for secondary GPUs. There was a deadlock between one thread trying to wait for a workqueue job to finish in the runtime suspend path, and the workqueue job it was waiting for in turn waiting for a runtime_get_sync to return. The fixes avoids it by not doing the runtime sync in the workqueue as then we always wait for all those tasks to complete before we runtime suspend" * tag 'drm-fixes-for-v4.16-rc3' of git://people.freedesktop.org/~airlied/linux: (25 commits) drm/tve200: fix kernel-doc documentation comment include drm/edid: quirk Sony PlayStation VR headset as non-desktop drm/edid: quirk Windows Mixed Reality headsets as non-desktop drm/edid: quirk Oculus Rift headsets as non-desktop drm/meson: fix vsync buffer update drm: Handle unexpected holes in color-eviction drm: exynos: Use proper macro definition for HDMI_I2S_PIN_SEL_1 drm/exynos: remove exynos_drm_rotator.h drm/exynos: g2d: Delete an error message for a failed memory allocation in two functions drm/exynos: fix comparison to bitshift when dealing with a mask drm/exynos: g2d: use monotonic timestamps drm/edid: Add 6 bpc quirk for CPT panel in Asus UX303LA gpu: ipu-csi: add 10/12-bit grayscale support to mbus_code_to_bus_cfg gpu: ipu-cpmem: add 16-bit grayscale support to ipu_cpmem_set_image gpu: ipu-v3: prg: fix device node leak in ipu_prg_lookup_by_phandle gpu: ipu-v3: pre: fix device node leak in ipu_pre_lookup_by_phandle drm/amdgpu: Fix deadlock on runtime suspend drm/radeon: Fix deadlock on runtime suspend drm/nouveau: Fix deadlock on runtime suspend drm: Allow determining if current task is output poll worker ...
2018-02-22genirq/matrix: Handle CPU offlining properThomas Gleixner
At CPU hotunplug the corresponding per cpu matrix allocator is shut down and the allocated interrupt bits are discarded under the assumption that all allocated bits have been either migrated away or shut down through the managed interrupts mechanism. This is not true because interrupts which are not started up might have a vector allocated on the outgoing CPU. When the interrupt is started up later or completely shutdown and freed then the allocated vector is handed back, triggering warnings or causing accounting issues which result in suspend failures and other issues. Change the CPU hotplug mechanism of the matrix allocator so that the remaining allocations at unplug time are preserved and global accounting at hotplug is correctly readjusted to take the dormant vectors into account. Fixes: 2f75d9e1c905 ("genirq: Implement bitmap matrix allocator") Reported-by: Yuriy Vostrikov <delamonpansie@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Yuriy Vostrikov <delamonpansie@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180222112316.849980972@linutronix.de
2018-02-22bpf: fix rcu lockdep warning for lpm_trie map_free callbackYonghong Song
Commit 9a3efb6b661f ("bpf: fix memory leak in lpm_trie map_free callback function") fixed a memory leak and removed unnecessary locks in map_free callback function. Unfortrunately, it introduced a lockdep warning. When lockdep checking is turned on, running tools/testing/selftests/bpf/test_lpm_map will have: [ 98.294321] ============================= [ 98.294807] WARNING: suspicious RCU usage [ 98.295359] 4.16.0-rc2+ #193 Not tainted [ 98.295907] ----------------------------- [ 98.296486] /home/yhs/work/bpf/kernel/bpf/lpm_trie.c:572 suspicious rcu_dereference_check() usage! [ 98.297657] [ 98.297657] other info that might help us debug this: [ 98.297657] [ 98.298663] [ 98.298663] rcu_scheduler_active = 2, debug_locks = 1 [ 98.299536] 2 locks held by kworker/2:1/54: [ 98.300152] #0: ((wq_completion)"events"){+.+.}, at: [<00000000196bc1f0>] process_one_work+0x157/0x5c0 [ 98.301381] #1: ((work_completion)(&map->work)){+.+.}, at: [<00000000196bc1f0>] process_one_work+0x157/0x5c0 Since actual trie tree removal happens only after no other accesses to the tree are possible, replacing rcu_dereference_protected(*slot, lockdep_is_held(&trie->lock)) with rcu_dereference_protected(*slot, 1) fixed the issue. Fixes: 9a3efb6b661f ("bpf: fix memory leak in lpm_trie map_free callback function") Reported-by: Eric Dumazet <edumazet@google.com> Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yonghong Song <yhs@fb.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-22bpf: add schedule points in percpu arrays managementEric Dumazet
syszbot managed to trigger RCU detected stalls in bpf_array_free_percpu() It takes time to allocate a huge percpu map, but even more time to free it. Since we run in process context, use cond_resched() to yield cpu if needed. Fixes: a10423b87a7e ("bpf: introduce BPF_MAP_TYPE_PERCPU_ARRAY map") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-22Merge tag 'seccomp-v4.16-rc3' of ↵James Morris
https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into fixes-v4.16-rc3 - Fix seccomp GET_METADATA to deal with field sizes correctly (Tycho Andersen) - Add selftest to make sure GET_METADATA doesn't regress (Tycho Andersen)
2018-02-22Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc fixes from Andrew Morton: "16 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mm: don't defer struct page initialization for Xen pv guests lib/Kconfig.debug: enable RUNTIME_TESTING_MENU vmalloc: fix __GFP_HIGHMEM usage for vmalloc_32 on 32b systems selftests/memfd: add run_fuse_test.sh to TEST_FILES bug.h: work around GCC PR82365 in BUG() mm/swap.c: make functions and their kernel-doc agree (again) mm/zpool.c: zpool_evictable: fix mismatch in parameter name and kernel-doc ida: do zeroing in ida_pre_get() mm, swap, frontswap: fix THP swap if frontswap enabled certs/blacklist_nohashes.c: fix const confusion in certs blacklist kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE mm, mlock, vmscan: no more skipping pagevecs mm: memcontrol: fix NR_WRITEBACK leak in memcg and system stats Kbuild: always define endianess in kconfig.h include/linux/sched/mm.h: re-inline mmdrop() tools: fix cross-compile var clobbering
2018-02-22efivarfs: Limit the rate for non-root to read filesLuck, Tony
Each read from a file in efivarfs results in two calls to EFI (one to get the file size, another to get the actual data). On X86 these EFI calls result in broadcast system management interrupts (SMI) which affect performance of the whole system. A malicious user can loop performing reads from efivarfs bringing the system to its knees. Linus suggested per-user rate limit to solve this. So we add a ratelimit structure to "user_struct" and initialize it for the root user for no limit. When allocating user_struct for other users we set the limit to 100 per second. This could be used for other places that want to limit the rate of some detrimental user action. In efivarfs if the limit is exceeded when reading, we take an interruptible nap for 50ms and check the rate limit again. Signed-off-by: Tony Luck <tony.luck@intel.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-21ptrace, seccomp: tweak get_metadata behavior slightlyTycho Andersen
Previously if users passed a small size for the input structure size, they would get get odd behavior. It doesn't make sense to pass a structure smaller than at least filter_off size, so let's just give -EINVAL in this case. This changes userspace visible behavior, but was only introduced in commit 26500475ac1b ("ptrace, seccomp: add support for retrieving seccomp metadata") in 4.16-rc2, so should be safe to change if merged before then. Reported-by: Eugene Syromiatnikov <esyr@redhat.com> Signed-off-by: Tycho Andersen <tycho@tycho.ws> CC: Kees Cook <keescook@chromium.org> CC: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2018-02-21kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZEDavid Rientjes
chan->n_subbufs is set by the user and relay_create_buf() does a kmalloc() of chan->n_subbufs * sizeof(size_t *). kmalloc_slab() will generate a warning when this fails if chan->subbufs * sizeof(size_t *) > KMALLOC_MAX_SIZE. Limit chan->n_subbufs to the maximum allowed kmalloc() size. Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802061216100.122576@chino.kir.corp.google.com Fixes: f6302f1bcd75 ("relay: prevent integer overflow in relay_open()") Signed-off-by: David Rientjes <rientjes@google.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-21include/linux/sched/mm.h: re-inline mmdrop()Andrew Morton
As Peter points out, Doing a CALL+RET for just the decrement is a bit silly. Fixes: d70f2a14b72a4bc ("include/linux/sched/mm.h: uninline mmdrop_async(), etc") Acked-by: Peter Zijlstra (Intel) <peterz@infraded.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-22Merge tag 'drm-misc-fixes-2018-02-21' of ↵Dave Airlie
git://anongit.freedesktop.org/drm/drm-misc into drm-fixes Fixes for 4.16. I contains fixes for deadlock on runtime suspend on few drivers, a memory leak on non-blocking commits, a crash on color-eviction. The is also meson and edid fixes, plus a fix for a doc warning. * tag 'drm-misc-fixes-2018-02-21' of git://anongit.freedesktop.org/drm/drm-misc: drm/tve200: fix kernel-doc documentation comment include drm/meson: fix vsync buffer update drm: Handle unexpected holes in color-eviction drm/edid: Add 6 bpc quirk for CPT panel in Asus UX303LA drm/amdgpu: Fix deadlock on runtime suspend drm/radeon: Fix deadlock on runtime suspend drm/nouveau: Fix deadlock on runtime suspend drm: Allow determining if current task is output poll worker workqueue: Allow retrieval of current task's work struct drm/atomic: Fix memleak on ERESTARTSYS during non-blocking commits
2018-02-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf 2018-02-20 The following pull-request contains BPF updates for your *net* tree. The main changes are: 1) Fix a memory leak in LPM trie's map_free() callback function, where the trie structure itself was not freed since initial implementation. Also a synchronize_rcu() was needed in order to wait for outstanding programs accessing the trie to complete, from Yonghong. 2) Fix sock_map_alloc()'s error path in order to correctly propagate the -EINVAL error in case of too large allocation requests. This was just recently introduced when fixing close hooks via ULP layer, fix from Eric. 3) Do not use GFP_ATOMIC in __cpu_map_entry_alloc(). Reason is that this will not work with the recent __ptr_ring_init_queue_alloc() conversion to kvmalloc_array(), where in case of fallback to vmalloc() that GFP flag is invalid, from Jason. 4) Fix two recent syzkaller warnings: i) fix bpf_prog_array_copy_to_user() when a prog query with a big number of ids was performed where we'd otherwise trigger a warning from allocator side, ii) fix a missing mlock precharge on arraymaps, from Daniel. 5) Two fixes for bpftool in order to avoid breaking JSON output when used in batch mode, from Quentin. 6) Move a pr_debug() in libbpf in order to avoid having an otherwise uninitialized variable in bpf_program__reloc_text(), from Jeremy. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-21extable: Make init_kernel_text() globalJosh Poimboeuf
Convert init_kernel_text() to a global function and use it in a few places instead of manually comparing _sinittext and _einittext. Note that kallsyms.h has a very similar function called is_kernel_inittext(), but its end check is inclusive. I'm not sure whether that's intentional behavior, so I didn't touch it. Suggested-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/4335d02be8d45ca7d265d2f174251d0b7ee6c5fd.1519051220.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-21jump_label: Warn on failed jump_label patching attemptJosh Poimboeuf
Currently when the jump label code encounters an address which isn't recognized by kernel_text_address(), it just silently fails. This can be dangerous because jump labels are used in a variety of places, and are generally expected to work. Convert the silent failure to a warning. This won't warn about attempted writes to tracepoints in __init code after initmem has been freed, as those are already guarded by the entry->code check. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@suse.de> Cc: Jason Baron <jbaron@akamai.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/de3a271c93807adb7ed48f4e946b4f9156617680.1519051220.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-21jump_label: Explicitly disable jump labels in __init codeJosh Poimboeuf
After initmem has been freed, any jump labels in __init code are prevented from being written to by the kernel_text_address() check in __jump_label_update(). However, this check is quite broad. If kernel_text_address() were to return false for any other reason, the jump label write would fail silently with no warning. For jump labels in module init code, entry->code is set to zero to indicate that the entry is disabled. Do the same thing for core kernel init code. This makes the behavior more consistent, and will also make it more straightforward to detect non-init jump label write failures in the next patch. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@suse.de> Cc: Jason Baron <jbaron@akamai.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/c52825c73f3a174e8398b6898284ec20d4deb126.1519051220.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-18Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Thomas Gleixner: "Perf tool updates and kprobe fixes: - perf_mmap overwrite mode fixes/overhaul, prep work to get 'perf top' using it, making it bearable to use it in large core count systems such as Knights Landing/Mill Intel systems (Kan Liang) - s/390 now uses syscall.tbl, just like x86-64 to generate the syscall table id -> string tables used by 'perf trace' (Hendrik Brueckner) - Use strtoull() instead of home grown function (Andy Shevchenko) - Synchronize kernel ABI headers, v4.16-rc1 (Ingo Molnar) - Document missing 'perf data --force' option (Sangwon Hong) - Add perf vendor JSON metrics for ARM Cortex-A53 Processor (William Cohen) - Improve error handling and error propagation of ftrace based kprobes so failures when installing kprobes are not silently ignored and create disfunctional tracepoints" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) kprobes: Propagate error from disarm_kprobe_ftrace() kprobes: Propagate error from arm_kprobe_ftrace() Revert "tools include s390: Grab a copy of arch/s390/include/uapi/asm/unistd.h" perf s390: Rework system call table creation by using syscall.tbl perf s390: Grab a copy of arch/s390/kernel/syscall/syscall.tbl tools/headers: Synchronize kernel ABI headers, v4.16-rc1 perf test: Fix test trace+probe_libc_inet_pton.sh for s390x perf data: Document missing --force option perf tools: Substitute yet another strtoull() perf top: Check the latency of perf_top__mmap_read() perf top: Switch default mode to overwrite mode perf top: Remove lost events checking perf hists browser: Add parameter to disable lost event warning perf top: Add overwrite fall back perf evsel: Expose the perf_missing_features struct perf top: Check per-event overwrite term perf mmap: Discard legacy interface for mmap read perf test: Update mmap read functions for backward-ring-buffer test perf mmap: Introduce perf_mmap__read_event() perf mmap: Introduce perf_mmap__read_done() ...
2018-02-18Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "A small set of updates mostly for irq chip drivers: - MIPS GIC fix for spurious, masked interrupts - fix for a subtle IPI bug in GICv3 - do not probe GICv3 ITSs that are marked as disabled - multi-MSI support for GICv2m - various small cleanups" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqdomain: Re-use DEFINE_SHOW_ATTRIBUTE() macro irqchip/bcm: Remove hashed address printing irqchip/gic-v2m: Add PCI Multi-MSI support irqchip/gic-v3: Ignore disabled ITS nodes irqchip/gic-v3: Use wmb() instead of smb_wmb() in gic_raise_softirq() irqchip/gic-v3: Change pr_debug message to pr_devel irqchip/mips-gic: Avoid spuriously handling masked interrupts
2018-02-16workqueue: Allow retrieval of current task's work structLukas Wunner
Introduce a helper to retrieve the current task's work struct if it is a workqueue worker. This allows us to fix a long-standing deadlock in several DRM drivers wherein the ->runtime_suspend callback waits for a specific worker to finish and that worker in turn calls a function which waits for runtime suspend to finish. That function is invoked from multiple call sites and waiting for runtime suspend to finish is the correct thing to do except if it's executing in the context of the worker. Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Dave Airlie <airlied@redhat.com> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Alex Deucher <alexander.deucher@amd.com> Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Lyude Paul <lyude@redhat.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://patchwork.freedesktop.org/patch/msgid/2d8f603074131eb87e588d2b803a71765bd3a2fd.1518338788.git.lukas@wunner.de
2018-02-16irqdomain: Re-use DEFINE_SHOW_ATTRIBUTE() macroAndy Shevchenko
...instead of open coding file operations followed by custom ->open() callbacks per each attribute. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-02-16kprobes: Propagate error from disarm_kprobe_ftrace()Jessica Yu
Improve error handling when disarming ftrace-based kprobes. Like with arm_kprobe_ftrace(), propagate any errors from disarm_kprobe_ftrace() so that we do not disable/unregister kprobes that are still armed. In other words, unregister_kprobe() and disable_kprobe() should not report success if the kprobe could not be disarmed. disarm_all_kprobes() keeps its current behavior and attempts to disarm all kprobes. It returns the last encountered error and gives a warning if not all probes could be disarmed. This patch is based on Petr Mladek's original patchset (patches 2 and 3) back in 2015, which improved kprobes error handling, found here: https://lkml.org/lkml/2015/2/26/452 However, further work on this had been paused since then and the patches were not upstreamed. Based-on-patches-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Jessica Yu <jeyu@kernel.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S . Miller <davem@davemloft.net> Cc: Jiri Kosina <jikos@kernel.org> Cc: Joe Lawrence <joe.lawrence@redhat.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Miroslav Benes <mbenes@suse.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/20180109235124.30886-3-jeyu@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-16kprobes: Propagate error from arm_kprobe_ftrace()Jessica Yu
Improve error handling when arming ftrace-based kprobes. Specifically, if we fail to arm a ftrace-based kprobe, register_kprobe()/enable_kprobe() should report an error instead of success. Previously, this has lead to confusing situations where register_kprobe() would return 0 indicating success, but the kprobe would not be functional if ftrace registration during the kprobe arming process had failed. We should therefore take any errors returned by ftrace into account and propagate this error so that we do not register/enable kprobes that cannot be armed. This can happen if, for example, register_ftrace_function() finds an IPMODIFY conflict (since kprobe_ftrace_ops has this flag set) and returns an error. Such a conflict is possible since livepatches also set the IPMODIFY flag for their ftrace_ops. arm_all_kprobes() keeps its current behavior and attempts to arm all kprobes. It returns the last encountered error and gives a warning if not all probes could be armed. This patch is based on Petr Mladek's original patchset (patches 2 and 3) back in 2015, which improved kprobes error handling, found here: https://lkml.org/lkml/2015/2/26/452 However, further work on this had been paused since then and the patches were not upstreamed. Based-on-patches-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Jessica Yu <jeyu@kernel.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S . Miller <davem@davemloft.net> Cc: Jiri Kosina <jikos@kernel.org> Cc: Joe Lawrence <joe.lawrence@redhat.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Miroslav Benes <mbenes@suse.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/20180109235124.30886-2-jeyu@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-15bpf: fix mlock precharge on arraymapsDaniel Borkmann
syzkaller recently triggered OOM during percpu map allocation; while there is work in progress by Dennis Zhou to add __GFP_NORETRY semantics for percpu allocator under pressure, there seems also a missing bpf_map_precharge_memlock() check in array map allocation. Given today the actual bpf_map_charge_memlock() happens after the find_and_alloc_map() in syscall path, the bpf_map_precharge_memlock() is there to bail out early before we go and do the map setup work when we find that we hit the limits anyway. Therefore add this for array map as well. Fixes: 6c9059817432 ("bpf: pre-allocate hash map elements") Fixes: a10423b87a7e ("bpf: introduce BPF_MAP_TYPE_PERCPU_ARRAY map") Reported-by: syzbot+adb03f3f0bb57ce3acda@syzkaller.appspotmail.com Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Dennis Zhou <dennisszhou@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-15Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "Misc fixes: - fix rq->lock lockdep annotation bug - fix/improve update_curr_rt() and update_curr_dl() accounting - update documentation - remove unused macro" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/cpufreq: Remove unused SUGOV_KTHREAD_PRIORITY macro sched/core: Fix DEBUG_SPINLOCK annotation for rq->lock sched/rt: Make update_curr_rt() more accurate sched/deadline: Make update_curr_dl() more accurate membarrier-sync-core: Document architecture support
2018-02-15Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Ingo Molnar: "This contains two qspinlock fixes and three documentation and comment fixes" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/semaphore: Update the file path in documentation locking/atomic/bitops: Document and clarify ordering semantics for failed test_and_{}_bit() locking/qspinlock: Ensure node->count is updated before initialising node locking/qspinlock: Ensure node is initialised before updating prev->next Documentation/locking/mutex-design: Update to reflect latest changes
2018-02-14bpf: fix bpf_prog_array_copy_to_user warning from perf event prog queryDaniel Borkmann
syzkaller tried to perform a prog query in perf_event_query_prog_array() where struct perf_event_query_bpf had an ids_len of 1,073,741,353 and thus causing a warning due to failed kcalloc() allocation out of the bpf_prog_array_copy_to_user() helper. Given we cannot attach more than 64 programs to a perf event, there's no point in allowing huge ids_len. Therefore, allow a buffer that would fix the maximum number of ids and also add a __GFP_NOWARN to the temporary ids buffer. Fixes: f371b304f12e ("bpf/tracing: allow user space to query prog array on the same tp") Fixes: 0911287ce32b ("bpf: fix bpf_prog_array_copy_to_user() issues") Reported-by: syzbot+cab5816b0edbabf598b3@syzkaller.appspotmail.com Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-14bpf: cpumap: use GFP_KERNEL instead of GFP_ATOMIC in __cpu_map_entry_alloc()Jason Wang
There're several implications after commit 0bf7800f1799 ("ptr_ring: try vmalloc() when kmalloc() fails") with the using of vmalloc() since can't allow GFP_ATOMIC but mandate GFP_KERNEL. This will lead a WARN since cpumap try to call with GFP_ATOMIC. Fortunately, entry allocation of cpumap can only be done through syscall path which means GFP_ATOMIC is not necessary, so fixing this by replacing GFP_ATOMIC with GFP_KERNEL. Reported-by: syzbot+1a240cdb1f4cc88819df@syzkaller.appspotmail.com Fixes: 0bf7800f1799 ("ptr_ring: try vmalloc() when kmalloc() fails") Cc: Michal Hocko <mhocko@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Jesper Dangaard Brouer <brouer@redhat.com> Cc: akpm@linux-foundation.org Cc: dhowells@redhat.com Cc: hannes@cmpxchg.org Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-13bpf: fix sock_map_alloc() error pathEric Dumazet
In case user program provides silly parameters, we want a map_alloc() handler to return an error, not a NULL pointer, otherwise we crash later in find_and_alloc_map() Fixes: 1aa12bdf1bfb ("bpf: sockmap, add sock close() hook to remove socks") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-13bpf: fix memory leak in lpm_trie map_free callback functionYonghong Song
There is a memory leak happening in lpm_trie map_free callback function trie_free. The trie structure itself does not get freed. Also, trie_free function did not do synchronize_rcu before freeing various data structures. This is incorrect as some rcu_read_lock region(s) for lookup, update, delete or get_next_key may not complete yet. The fix is to add synchronize_rcu in the beginning of trie_free. The useless spin_lock is removed from this function as well. Fixes: b95a5c4db09b ("bpf: add a longest prefix match trie map implementation") Reported-by: Mathieu Malaterre <malat@debian.org> Reported-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-13locking/qspinlock: Ensure node->count is updated before initialising nodeWill Deacon
When queuing on the qspinlock, the count field for the current CPU's head node is incremented. This needn't be atomic because locking in e.g. IRQ context is balanced and so an IRQ will return with node->count as it found it. However, the compiler could in theory reorder the initialisation of node[idx] before the increment of the head node->count, causing an IRQ to overwrite the initialised node and potentially corrupt the lock state. Avoid the potential for this harmful compiler reordering by placing a barrier() between the increment of the head node->count and the subsequent node initialisation. Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1518528177-19169-3-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-13locking/qspinlock: Ensure node is initialised before updating prev->nextWill Deacon
When a locker ends up queuing on the qspinlock locking slowpath, we initialise the relevant mcs node and publish it indirectly by updating the tail portion of the lock word using xchg_tail. If we find that there was a pre-existing locker in the queue, we subsequently update their ->next field to point at our node so that we are notified when it's our turn to take the lock. This can be roughly illustrated as follows: /* Initialise the fields in node and encode a pointer to node in tail */ tail = initialise_node(node); /* * Exchange tail into the lockword using an atomic read-modify-write * operation with release semantics */ old = xchg_tail(lock, tail); /* If there was a pre-existing waiter ... */ if (old & _Q_TAIL_MASK) { prev = decode_tail(old); smp_read_barrier_depends(); /* ... then update their ->next field to point to node. WRITE_ONCE(prev->next, node); } The conditional update of prev->next therefore relies on the address dependency from the result of xchg_tail ensuring order against the prior initialisation of node. However, since the release semantics of the xchg_tail operation apply only to the write portion of the RmW, then this ordering is not guaranteed and it is possible for the CPU to return old before the writes to node have been published, consequently allowing us to point prev->next to an uninitialised node. This patch fixes the problem by making the update of prev->next a RELEASE operation, which also removes the reliance on dependency ordering. Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1518528177-19169-2-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-13sched/cpufreq: Remove unused SUGOV_KTHREAD_PRIORITY macroLeo Yan
Since schedutil kernel thread directly set priority to 0, the macro SUGOV_KTHREAD_PRIORITY is not used. So remove it. Signed-off-by: Leo Yan <leo.yan@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vikram Mulukutla <markivx@codeaurora.org> Cc: