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2020-04-19Merge tag 'timers-urgent-2020-04-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull time namespace fix from Thomas Gleixner: "An update for the proc interface of time namespaces: Use symbolic names instead of clockid numbers. The usability nuisance of numbers was noticed by Michael when polishing the man page" * tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets
2020-04-19Merge tag 'irq-urgent-2020-04-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: "A set of fixes/updates for the interrupt subsystem: - Remove setup_irq() and remove_irq(). All users have been converted so remove them before new users surface. - A set of bugfixes for various interrupt chip drivers - Add a few missing static attributes to address sparse warnings" * tag 'irq-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/irq-bcm7038-l1: Make bcm7038_l1_of_init() static irqchip/irq-mvebu-icu: Make legacy_bindings static irqchip/meson-gpio: Fix HARDIRQ-safe -> HARDIRQ-unsafe lock order irqchip/sifive-plic: Fix maximum priority threshold value irqchip/ti-sci-inta: Fix processing of masked irqs irqchip/mbigen: Free msi_desc on device teardown irqchip/gic-v4.1: Update effective affinity of virtual SGIs irqchip/gic-v4.1: Add support for VPENDBASER's Dirty+Valid signaling genirq: Remove setup_irq() and remove_irq()
2020-04-19Merge tag 'sched-urgent-2020-04-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "Two fixes for the scheduler: - Work around an uninitialized variable warning where GCC can't figure it out. - Allow 'isolcpus=' to skip unknown subparameters so that older kernels work with the commandline of a newer kernel. Improve the error output while at it" * tag 'sched-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/vtime: Work around an unitialized variable warning sched/isolation: Allow "isolcpus=" to skip unknown sub-parameters
2020-04-19Merge tag 'core-urgent-2020-04-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU fix from Thomas Gleixner: "A single bugfix for RCU to prevent taking a lock in NMI context" * tag 'core-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rcu: Don't acquire lock in NMI handler in rcu_nmi_enter_common()
2020-04-18Merge tag 'for-linus-2020-04-18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull thread fixes from Christian Brauner: "A few fixes and minor improvements: - Correctly validate the cgroup file descriptor when clone3() is used with CLONE_INTO_CGROUP. - Check that a new enough version of struct clone_args is passed which supports the cgroup file descriptor argument when CLONE_INTO_CGROUP is set in the flags argument. - Catch nonsensical struct clone_args layouts at build time. - Catch extensions of struct clone_args without updating the uapi visible size definitions at build time. - Check whether the signal is valid early in kill_pid_usb_asyncio() before doing further work. - Replace open-coded rcu_read_lock()+kill_pid_info()+rcu_read_unlock() sequence in kill_something_info() with kill_proc_info() which is a dedicated helper to do just that" * tag 'for-linus-2020-04-18' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: clone3: add build-time CLONE_ARGS_SIZE_VER* validity checks clone3: add a check for the user struct size if CLONE_INTO_CGROUP is set clone3: fix cgroup argument sanity check signal: use kill_proc_info instead of kill_pid_info in kill_something_info signal: check sig before setting info in kill_pid_usb_asyncio
2020-04-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds
Pull networking fixes from David Miller: 1) Disable RISCV BPF JIT builds when !MMU, from Björn Töpel. 2) nf_tables leaves dangling pointer after free, fix from Eric Dumazet. 3) Out of boundary write in __xsk_rcv_memcpy(), fix from Li RongQing. 4) Adjust icmp6 message source address selection when routes have a preferred source address set, from Tim Stallard. 5) Be sure to validate HSR protocol version when creating new links, from Taehee Yoo. 6) CAP_NET_ADMIN should be sufficient to manage l2tp tunnels even in non-initial namespaces, from Michael Weiß. 7) Missing release firmware call in mlx5, from Eran Ben Elisha. 8) Fix variable type in macsec_changelink(), caught by KASAN. Fix from Taehee Yoo. 9) Fix pause frame negotiation in marvell phy driver, from Clemens Gruber. 10) Record RX queue early enough in tun packet paths such that XDP programs will see the correct RX queue index, from Gilberto Bertin. 11) Fix double unlock in mptcp, from Florian Westphal. 12) Fix offset overflow in ARM bpf JIT, from Luke Nelson. 13) marvell10g needs to soft reset PHY when coming out of low power mode, from Russell King. 14) Fix MTU setting regression in stmmac for some chip types, from Florian Fainelli. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (101 commits) amd-xgbe: Use __napi_schedule() in BH context mISDN: make dmril and dmrim static net: stmmac: dwmac-sunxi: Provide TX and RX fifo sizes net: dsa: mt7530: fix tagged frames pass-through in VLAN-unaware mode tipc: fix incorrect increasing of link window Documentation: Fix tcp_challenge_ack_limit default value net: tulip: make early_486_chipsets static dt-bindings: net: ethernet-phy: add desciption for ethernet-phy-id1234.d400 ipv6: remove redundant assignment to variable err net/rds: Use ERR_PTR for rds_message_alloc_sgs() net: mscc: ocelot: fix untagged packet drops when enslaving to vlan aware bridge selftests/bpf: Check for correct program attach/detach in xdp_attach test libbpf: Fix type of old_fd in bpf_xdp_set_link_opts libbpf: Always specify expected_attach_type on program load if supported xsk: Add missing check on user supplied headroom size mac80211: fix channel switch trigger from unknown mesh peer mac80211: fix race in ieee80211_register_hw() net: marvell10g: soft-reset the PHY when coming out of low power net: marvell10g: report firmware version net/cxgb4: Check the return from t4_query_params properly ...
2020-04-16proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsetsAndrei Vagin
Michael Kerrisk suggested to replace numeric clock IDs with symbolic names. Now the content of these files looks like this: $ cat /proc/774/timens_offsets monotonic 864000 0 boottime 1728000 0 For setting offsets, both representations of clocks (numeric and symbolic) can be used. As for compatibility, it is acceptable to change things as long as userspace doesn't care. The format of timens_offsets files is very new and there are no userspace tools yet which rely on this format. But three projects crun, util-linux and criu rely on the interface of setting time offsets and this is why it's required to continue supporting the numeric clock IDs on write. Fixes: 04a8682a71be ("fs/proc: Introduce /proc/pid/timens_offsets") Suggested-by: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kerrisk <mtk.manpages@gmail.com> Acked-by: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20200411154031.642557-1-avagin@gmail.com
2020-04-15sched/vtime: Work around an unitialized variable warningBorislav Petkov
Work around this warning: kernel/sched/cputime.c: In function ‘kcpustat_field’: kernel/sched/cputime.c:1007:6: warning: ‘val’ may be used uninitialized in this function [-Wmaybe-uninitialized] because GCC can't see that val is used only when err is 0. Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200327214334.GF8015@zn.tnic
2020-04-15sched/isolation: Allow "isolcpus=" to skip unknown sub-parametersPeter Xu
The "isolcpus=" parameter allows sub-parameters before the cpulist is specified, and if the parser detects an unknown sub-parameters the whole parameter will be ignored. This design is incompatible with itself when new sub-parameters are added. An older kernel will not recognize the new sub-parameter and will invalidate the whole parameter so the CPU isolation will not take effect. It emits a warning: isolcpus: Error, unknown flag The better and compatible way is to allow "isolcpus=" to skip unknown sub-parameters, so that even if new sub-parameters are added an older kernel will still be able to behave as usual even if with the new sub-parameter specified on the command line. Ideally this should have been there when the first sub-parameter for "isolcpus=" was introduced. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200403223517.406353-1-peterx@redhat.com
2020-04-15clone3: add build-time CLONE_ARGS_SIZE_VER* validity checksEugene Syromiatnikov
CLONE_ARGS_SIZE_VER* macros are defined explicitly and not via the offsets of the relevant struct clone_args fields, which makes it rather error-prone, so it probably makes sense to add some compile-time checks for them (including the one that breaks on struct clone_args extension as a reminder to add a relevant size macro and a similar check). Function copy_clone_args_from_user seems to be a good place for such checks. Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Link: https://lore.kernel.org/r/20200412202658.GA31499@asgard.redhat.com Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-04-15clone3: add a check for the user struct size if CLONE_INTO_CGROUP is setEugene Syromiatnikov
Passing CLONE_INTO_CGROUP with an under-sized structure (that doesn't properly contain cgroup field) seems like garbage input, especially considering the fact that fd 0 is a valid descriptor. Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Link: https://lore.kernel.org/r/20200412203123.GA5869@asgard.redhat.com Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-04-15clone3: fix cgroup argument sanity checkEugene Syromiatnikov
Checking that cgroup field value of struct clone_args is less than 0 is useless, as it is defined as unsigned 64-bit integer. Moreover, it doesn't catch the situations where its higher bits are lost during the assignment to the cgroup field of the cgroup field of the internal struct kernel_clone_args (where it is declared as signed 32-bit integer), so it is still possible to pass garbage there. A check against INT_MAX solves both these issues. Fixes: ef2c41cf38a7559b ("clone3: allow spawning processes into cgroups") Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Link: https://lore.kernel.org/r/20200412202533.GA29554@asgard.redhat.com Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-04-14tracing: Fix the race between registering 'snapshot' event trigger and ↵Xiao Yang
triggering 'snapshot' operation Traced event can trigger 'snapshot' operation(i.e. calls snapshot_trigger() or snapshot_count_trigger()) when register_snapshot_trigger() has completed registration but doesn't allocate buffer for 'snapshot' event trigger. In the rare case, 'snapshot' operation always detects the lack of allocated buffer so make register_snapshot_trigger() allocate buffer first. trigger-snapshot.tc in kselftest reproduces the issue on slow vm: ----------------------------------------------------------- cat trace ... ftracetest-3028 [002] .... 236.784290: sched_process_fork: comm=ftracetest pid=3028 child_comm=ftracetest child_pid=3036 <...>-2875 [003] .... 240.460335: tracing_snapshot_instance_cond: *** SNAPSHOT NOT ALLOCATED *** <...>-2875 [003] .... 240.460338: tracing_snapshot_instance_cond: *** stopping trace here! *** ----------------------------------------------------------- Link: http://lkml.kernel.org/r/20200414015145.66236-1-yangx.jy@cn.fujitsu.com Cc: stable@vger.kernel.org Fixes: 93e31ffbf417a ("tracing: Add 'snapshot' event trigger command") Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-04-14bpf: remove unneeded conversion to bool in __mark_reg_unknownZou Wei
This issue was detected by using the Coccinelle software: kernel/bpf/verifier.c:1259:16-21: WARNING: conversion to bool not needed here The conversion to bool is unneeded, remove it. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zou Wei <zou_wei@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/1586779076-101346-1-git-send-email-zou_wei@huawei.com
2020-04-14bpf: Prevent re-mmap()'ing BPF map as writable for initially r/o mappingAndrii Nakryiko
VM_MAYWRITE flag during initial memory mapping determines if already mmap()'ed pages can be later remapped as writable ones through mprotect() call. To prevent user application to rewrite contents of memory-mapped as read-only and subsequently frozen BPF map, remove VM_MAYWRITE flag completely on initially read-only mapping. Alternatively, we could treat any memory-mapping on unfrozen map as writable and bump writecnt instead. But there is little legitimate reason to map BPF map as read-only and then re-mmap() it as writable through mprotect(), instead of just mmap()'ing it as read/write from the very beginning. Also, at the suggestion of Jann Horn, drop unnecessary refcounting in mmap operations. We can just rely on VMA holding reference to BPF map's file properly. Fixes: fc9702273e2e ("bpf: Add mmap() support for BPF_MAP_TYPE_ARRAY") Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jann Horn <jannh@google.com> Link: https://lore.kernel.org/bpf/20200410202613.3679837-1-andriin@fb.com
2020-04-14genirq: Remove setup_irq() and remove_irq()afzal mohammed
Now that all the users of setup_irq() & remove_irq() have been replaced by request_irq() & free_irq() respectively, delete them. Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lkml.kernel.org/r/0aa8771ada1ac8e1312f6882980c9c08bd023148.1585320721.git.afzal.mohd.ma@gmail.com
2020-04-14Merge branch 'urgent-for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent Pull RCU fix from Paul E. McKenney. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-12signal: use kill_proc_info instead of kill_pid_info in kill_something_infoZhiqiang Liu
signal.c provides kill_proc_info, we can use it instead of kill_pid_info in kill_something_info func gracefully. Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Link: https://lore.kernel.org/r/80236965-f0b5-c888-95ff-855bdec75bb3@huawei.com Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-04-12signal: check sig before setting info in kill_pid_usb_asyncioZhiqiang Liu
In kill_pid_usb_asyncio, if signal is not valid, we do not need to set info struct. Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Link: https://lore.kernel.org/r/f525fd08-1cf7-fb09-d20c-4359145eb940@huawei.com Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-04-12Merge tag 'timers-urgent-2020-04-12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull time(keeping) updates from Thomas Gleixner: - Fix the time_for_children symlink in /proc/$PID/ so it properly reflects that it part of the 'time' namespace - Add the missing userns limit for the allowed number of time namespaces, which was half defined but the actual array member was not added. This went unnoticed as the array has an exessive empty member at the end but introduced a user visible regression as the output was corrupted. - Prevent further silent ucount corruption by adding a BUILD_BUG_ON() to catch half updated data. * tag 'timers-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ucount: Make sure ucounts in /proc/sys/user don't regress again time/namespace: Add max_time_namespaces ucount time/namespace: Fix time_for_children symlink
2020-04-12Merge tag 'sched-urgent-2020-04-12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes/updates from Thomas Gleixner: - Deduplicate the average computations in the scheduler core and the fair class code. - Fix a raise between runtime distribution and assignement which can cause exceeding the quota by up to 70%. - Prevent negative results in the imbalanace calculation - Remove a stale warning in the workqueue code which can be triggered since the call site was moved out of preempt disabled code. It's a false positive. - Deduplicate the print macros for procfs - Add the ucmap values to the SCHED_DEBUG procfs output for completness * tag 'sched-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/debug: Add task uclamp values to SCHED_DEBUG procfs sched/debug: Factor out printing formats into common macros sched/debug: Remove redundant macro define sched/core: Remove unused rq::last_load_update_tick workqueue: Remove the warning in wq_worker_sleeping() sched/fair: Fix negative imbalance in imbalance calculation sched/fair: Fix race between runtime distribution and assignment sched/fair: Align rq->avg_idle and rq->avg_scan_cost
2020-04-12Merge tag 'perf-urgent-2020-04-12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "Three fixes/updates for perf: - Fix the perf event cgroup tracking which tries to track the cgroup even for disabled events. - Add Ice Lake server support for uncore events - Disable pagefaults when retrieving the physical address in the sampling code" * tag 'perf-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Disable page faults when getting phys address perf/x86/intel/uncore: Add Ice Lake server uncore support perf/cgroup: Correct indirection in perf_less_group_idx() perf/core: Fix event cgroup tracking
2020-04-12Merge tag 'locking-urgent-2020-04-12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Thomas Gleixner: "Three small fixes/updates for the locking core code: - Plug a task struct reference leak in the percpu rswem implementation. - Document the refcount interaction with PID_MAX_LIMIT - Improve the 'invalid wait context' data dump in lockdep so it contains all information which is required to decode the problem" * tag 'locking-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/lockdep: Improve 'invalid wait context' splat locking/refcount: Document interaction with PID_MAX_LIMIT locking/percpu-rwsem: Fix a task_struct refcount
2020-04-11Merge tag 'dma-mapping-5.7-1' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds
Pull dma-mapping fixes from Christoph Hellwig: - fix an integer truncation in dma_direct_get_required_mask (Kishon Vijay Abraham) - fix the display of dma mapping types (Grygorii Strashko) * tag 'dma-mapping-5.7-1' of git://git.infradead.org/users/hch/dma-mapping: dma-debug: fix displaying of dma allocation type dma-direct: fix data truncation in dma_direct_get_required_mask()
2020-04-10Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge yet more updates from Andrew Morton: - Almost all of the rest of MM (memcg, slab-generic, slab, pagealloc, gup, hugetlb, pagemap, memremap) - Various other things (hfs, ocfs2, kmod, misc, seqfile) * akpm: (34 commits) ipc/util.c: sysvipc_find_ipc() should increase position index kernel/gcov/fs.c: gcov_seq_next() should increase position index fs/seq_file.c: seq_read(): add info message about buggy .next functions drivers/dma/tegra20-apb-dma.c: fix platform_get_irq.cocci warnings change email address for Pali Rohár selftests: kmod: test disabling module autoloading selftests: kmod: fix handling test numbers above 9 docs: admin-guide: document the kernel.modprobe sysctl fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once() kmod: make request_module() return an error when autoloading is disabled mm/memremap: set caching mode for PCI P2PDMA memory to WC mm/memory_hotplug: add pgprot_t to mhp_params powerpc/mm: thread pgprot_t through create_section_mapping() x86/mm: introduce __set_memory_prot() x86/mm: thread pgprot_t through init_memory_mapping() mm/memory_hotplug: rename mhp_restrictions to mhp_params mm/memory_hotplug: drop the flags field from struct mhp_restrictions mm/special: create generic fallbacks for pte_special() and pte_mkspecial() mm/vma: introduce VM_ACCESS_FLAGS mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS ...
2020-04-10kernel/gcov/fs.c: gcov_seq_next() should increase position indexVasily Averin
If seq_file .next function does not change position index, read after some lseek can generate unexpected output. https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: NeilBrown <neilb@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Waiman Long <longman@redhat.com> Link: http://lkml.kernel.org/r/f65c6ee7-bd00-f910-2f8a-37cc67e4ff88@virtuozzo.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10kmod: make request_module() return an error when autoloading is disabledEric Biggers
Patch series "module autoloading fixes and cleanups", v5. This series fixes a bug where request_module() was reporting success to kernel code when module autoloading had been completely disabled via 'echo > /proc/sys/kernel/modprobe'. It also addresses the issues raised on the original thread (https://lkml.kernel.org/lkml/20200310223731.126894-1-ebiggers@kernel.org/T/#u) bydocumenting the modprobe sysctl, adding a self-test for the empty path case, and downgrading a user-reachable WARN_ONCE(). This patch (of 4): It's long been possible to disable kernel module autoloading completely (while still allowing manual module insertion) by setting /proc/sys/kernel/modprobe to the empty string. This can be preferable to setting it to a nonexistent file since it avoids the overhead of an attempted execve(), avoids potential deadlocks, and avoids the call to security_kernel_module_request() and thus on SELinux-based systems eliminates the need to write SELinux rules to dontaudit module_request. However, when module autoloading is disabled in this way, request_module() returns 0. This is broken because callers expect 0 to mean that the module was successfully loaded. Apparently this was never noticed because this method of disabling module autoloading isn't used much, and also most callers don't use the return value of request_module() since it's always necessary to check whether the module registered its functionality or not anyway. But improperly returning 0 can indeed confuse a few callers, for example get_fs_type() in fs/filesystems.c where it causes a WARNING to be hit: if (!fs && (request_module("fs-%.*s", len, name) == 0)) { fs = __get_fs_type(name, len); WARN_ONCE(!fs, "request_module fs-%.*s succeeded, but still no fs?\n", len, name); } This is easily reproduced with: echo > /proc/sys/kernel/modprobe mount -t NONEXISTENT none / It causes: request_module fs-NONEXISTENT succeeded, but still no fs? WARNING: CPU: 1 PID: 1106 at fs/filesystems.c:275 get_fs_type+0xd6/0xf0 [...] This should actually use pr_warn_once() rather than WARN_ONCE(), since it's also user-reachable if userspace immediately unloads the module. Regardless, request_module() should correctly return an error when it fails. So let's make it return -ENOENT, which matches the error when the modprobe binary doesn't exist. I've also sent patches to document and test this case. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Jessica Yu <jeyu@kernel.org> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jeff Vander Stoep <jeffv@google.com> Cc: Ben Hutchings <benh@debian.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200310223731.126894-1-ebiggers@kernel.org Link: http://lkml.kernel.org/r/20200312202552.241885-1-ebiggers@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10printk: queue wake_up_klogd irq_work only if per-CPU areas are readySergey Senozhatsky
printk_deferred(), similarly to printk_safe/printk_nmi, does not immediately attempt to print a new message on the consoles, avoiding calls into non-reentrant kernel paths, e.g. scheduler or timekeeping, which potentially can deadlock the system. Those printk() flavors, instead, rely on per-CPU flush irq_work to print messages from safer contexts. For same reasons (recursive scheduler or timekeeping calls) printk() uses per-CPU irq_work in order to wake up user space syslog/kmsg readers. However, only printk_safe/printk_nmi do make sure that per-CPU areas have been initialised and that it's safe to modify per-CPU irq_work. This means that, for instance, should printk_deferred() be invoked "too early", that is before per-CPU areas are initialised, printk_deferred() will perform illegal per-CPU access. Lech Perczak [0] reports that after commit 1b710b1b10ef ("char/random: silence a lockdep splat with printk()") user-space syslog/kmsg readers are not able to read new kernel messages. The reason is printk_deferred() being called too early (as was pointed out by Petr and John). Fix printk_deferred() and do not queue per-CPU irq_work before per-CPU areas are initialized. Link: https://lore.kernel.org/lkml/aa0732c6-5c4e-8a8b-a1c1-75ebe3dca05b@camlintechnologies.com/ Reported-by: Lech Perczak <l.perczak@camlintechnologies.com> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Tested-by: Jann Horn <jannh@google.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Theodore Ts'o <tytso@mit.edu> Cc: John Ogness <john.ogness@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull proc fix from Eric Biederman: "A brown paper bag slipped through my proc changes, and syzcaller caught it when the code ended up in your tree. I have opted to fix it the simplest cleanest way I know how, so there is no reasonable chance for the bug to repeat" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: proc: Use a dedicated lock in struct pid
2020-04-10Merge tag 'pm-5.7-rc1-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management updates from Rafael Wysocki: "Rework compat ioctl handling in the user space hibernation interface (Christoph Hellwig) and fix a typo in a function name in the cpuidle haltpoll driver (Yihao Wu)" * tag 'pm-5.7-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpuidle-haltpoll: Fix small typo PM / sleep: handle the compat case in snapshot_set_swap_area() PM / sleep: move SNAPSHOT_SET_SWAP_AREA handling into a helper
2020-04-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf 2020-04-10 The following pull-request contains BPF updates for your *net* tree. We've added 13 non-merge commits during the last 7 day(s) which contain a total of 13 files changed, 137 insertions(+), 43 deletions(-). The main changes are: 1) JIT code emission fixes for riscv and arm32, from Luke Nelson and Xi Wang. 2) Disable vmlinux BTF info if GCC_PLUGIN_RANDSTRUCT is used, from Slava Bacherikov. 3) Fix oob write in AF_XDP when meta data is used, from Li RongQing. 4) Fix bpf_get_link_xdp_id() handling on single prog when flags are specified, from Andrey Ignatov. 5) Fix sk_assign() BPF helper for request sockets that can have sk_reuseport field uninitialized, from Joe Stringer. 6) Fix mprotect() test case for the BPF LSM, from KP Singh. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-09Merge tag 'modules-for-v5.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull module updates from Jessica Yu: "Only a small cleanup this time around: a trivial conversion of zero-length arrays to flexible arrays" * tag 'modules-for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: kernel: module: Replace zero-length array with flexible-array member
2020-04-09proc: Use a dedicated lock in struct pidEric W. Biederman
syzbot wrote: > ======================================================== > WARNING: possible irq lock inversion dependency detected > 5.6.0-syzkaller #0 Not tainted > -------------------------------------------------------- > swapper/1/0 just changed the state of lock: > ffffffff898090d8 (tasklist_lock){.+.?}-{2:2}, at: send_sigurg+0x9f/0x320 fs/fcntl.c:840 > but this lock took another, SOFTIRQ-unsafe lock in the past: > (&pid->wait_pidfd){+.+.}-{2:2} > > > and interrupts could create inverse lock ordering between them. > > > other info that might help us debug this: > Possible interrupt unsafe locking scenario: > > CPU0 CPU1 > ---- ---- > lock(&pid->wait_pidfd); > local_irq_disable(); > lock(tasklist_lock); > lock(&pid->wait_pidfd); > <Interrupt> > lock(tasklist_lock); > > *** DEADLOCK *** > > 4 locks held by swapper/1/0: The problem is that because wait_pidfd.lock is taken under the tasklist lock. It must always be taken with irqs disabled as tasklist_lock can be taken from interrupt context and if wait_pidfd.lock was already taken this would create a lock order inversion. Oleg suggested just disabling irqs where I have added extra calls to wait_pidfd.lock. That should be safe and I think the code will eventually do that. It was rightly pointed out by Christian that sharing the wait_pidfd.lock was a premature optimization. It is also true that my pre-merge window testing was insufficient. So remove the premature optimization and give struct pid a dedicated lock of it's own for struct pid things. I have verified that lockdep sees all 3 paths where we take the new pid->lock and lockdep does not complain. It is my current day dream that one day pid->lock can be used to guard the task lists as well and then the tasklist_lock won't need to be held to deliver signals. That will require taking pid->lock with irqs disabled. Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Link: https://lore.kernel.org/lkml/00000000000011d66805a25cd73f@google.com/ Cc: Oleg Nesterov <oleg@redhat.com> Cc: Christian Brauner <christian.brauner@ubuntu.com> Reported-by: syzbot+343f75cdeea091340956@syzkaller.appspotmail.com Reported-by: syzbot+832aabf700bc3ec920b9@syzkaller.appspotmail.com Reported-by: syzbot+f675f964019f884dbd0f@syzkaller.appspotmail.com Reported-by: syzbot+a9fb1457d720a55d6dc5@syzkaller.appspotmail.com Fixes: 7bc3e6e55acf ("proc: Use a list of inodes to flush from proc") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-04-08dma-debug: fix displaying of dma allocation typeGrygorii Strashko
The commit 2e05ea5cdc1a ("dma-mapping: implement dma_map_single_attrs using dma_map_page_attrs") removed "dma_debug_page" enum, but missed to update type2name string table. This causes incorrect displaying of dma allocation type. Fix it by removing "page" string from type2name string table and switch to use named initializers. Before (dma_alloc_coherent()): k3-ringacc 4b800000.ringacc: scather-gather idx 2208 P=d1140000 N=d114 D=d1140000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable k3-ringacc 4b800000.ringacc: scather-gather idx 2216 P=d1150000 N=d115 D=d1150000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable After: k3-ringacc 4b800000.ringacc: coherent idx 2208 P=d1140000 N=d114 D=d1140000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable k3-ringacc 4b800000.ringacc: coherent idx 2216 P=d1150000 N=d115 D=d1150000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable Fixes: 2e05ea5cdc1a ("dma-mapping: implement dma_map_single_attrs using dma_map_page_attrs") Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-04-08dma-direct: fix data truncation in dma_direct_get_required_mask()Kishon Vijay Abraham I
The upper 32-bit physical address gets truncated inadvertently when dma_direct_get_required_mask() invokes phys_to_dma_direct(). This results in dma_addressing_limited() return incorrect value when used in platforms with LPAE enabled. Fix it here by explicitly type casting 'max_pfn' to phys_addr_t in order to prevent overflow of intermediate value while evaluating '(max_pfn - 1) << PAGE_SHIFT'. Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-04-08locking/lockdep: Improve 'invalid wait context' splatPeter Zijlstra
The 'invalid wait context' splat doesn't print all the information required to reconstruct / validate the error, specifically the irq-context state is missing. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-08locking/percpu-rwsem: Fix a task_struct refcountQian Cai
The following commit: 7f26482a872c ("locking/percpu-rwsem: Remove the embedded rwsem") introduced task_struct memory leaks due to messing up the task_struct refcount. At the beginning of percpu_rwsem_wake_function(), it calls get_task_struct(), but if the trylock failed, it will remain in the waitqueue. However, it will run percpu_rwsem_wake_function() again with get_task_struct() to increase the refcount but then only call put_task_struct() once the trylock succeeded. Fix it by adjusting percpu_rwsem_wake_function() a bit to guard against when percpu_rwsem_wait() observing !private, terminating the wait and doing a quick exit() while percpu_rwsem_wake_function() then doing wake_up_process(p) as a use-after-free. Fixes: 7f26482a872c ("locking/percpu-rwsem: Remove the embedded rwsem") Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200330213002.2374-1-cai@lca.pw
2020-04-08sched/debug: Add task uclamp values to SCHED_DEBUG procfsValentin Schneider
Requested and effective uclamp values can be a bit tricky to decipher when playing with cgroup hierarchies. Add them to a task's procfs when SCHED_DEBUG is enabled. Reviewed-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200226124543.31986-4-valentin.schneider@arm.com
2020-04-08sched/debug: Factor out printing formats into common macrosValentin Schneider
The printing macros in debug.c keep redefining the same output format. Collect each output format in a single definition, and reuse that definition in the other macros. While at it, add a layer of parentheses and replace printf's with the newly introduced macros. Reviewed-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200226124543.31986-3-valentin.schneider@arm.com
2020-04-08sched/debug: Remove redundant macro defineValentin Schneider
Most printing macros for procfs are defined globally in debug.c, and they are re-defined (to the exact same thing) within proc_sched_show_task(). Get rid of the duplicate defines. Reviewed-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200226124543.31986-2-valentin.schneider@arm.com
2020-04-08sched/core: Remove unused rq::last_load_update_tickVincent Donnefort
The following commit: 5e83eafbfd3b ("sched/fair: Remove the rq->cpu_load[] update code") eliminated the last use case for rq->last_load_update_tick, so remove the field as well. Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Vincent Donnefort <vincent.donnefort@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/1584710495-308969-1-git-send-email-vincent.donnefort@arm.com
2020-04-08workqueue: Remove the warning in wq_worker_sleeping()Sebastian Andrzej Siewior
The kernel test robot triggered a warning with the following race: task-ctx A interrupt-ctx B worker -> process_one_work() -> work_item() -> schedule(); -> sched_submit_work() -> wq_worker_sleeping() -> ->sleeping = 1 atomic_dec_and_test(nr_running) __schedule(); *interrupt* async_page_fault() -> local_irq_enable(); -> schedule(); -> sched_submit_work() -> wq_worker_sleeping() -> if (WARN_ON(->sleeping)) return -> __schedule() -> sched_update_worker() -> wq_worker_running() -> atomic_inc(nr_running); -> ->sleeping = 0; -> sched_update_worker() -> wq_worker_running() if (!->sleeping) return In this context the warning is pointless everything is fine. An interrupt before wq_worker_sleeping() will perform the ->sleeping assignment (0 -> 1 > 0) twice. An interrupt after wq_worker_sleeping() will trigger the warning and nr_running will be decremented (by A) and incremented once (only by B, A will skip it). This is the case until the ->sleeping is zeroed again in wq_worker_running(). Remove the WARN statement because this condition may happen. Document that preemption around wq_worker_sleeping() needs to be disabled to protect ->sleeping and not just as an optimisation. Fixes: 6d25be5782e48 ("sched/core, workqueues: Distangle worker accounting from rq lock") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Tejun Heo <tj@kernel.org> Link: https://lkml.kernel.org/r/20200327074308.GY11705@shao2-debian
2020-04-08sched/fair: Fix negative imbalance in imbalance calculationAubrey Li
A negative imbalance value was observed after imbalance calculation, this happens when the local sched group type is group_fully_busy, and the average load of local group is greater than the selected busiest group. Fix this problem by comparing the average load of the local and busiest group before imbalance calculation formula. Suggested-by: Vincent Guittot <vincent.guittot@linaro.org> Reviewed-by: Phil Auld <pauld@redhat.com> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/1585201349-70192-1-git-send-email-aubrey.li@intel.com
2020-04-08sched/fair: Fix race between runtime distribution and assignmentHuaixin Chang
Currently, there is a potential race between distribute_cfs_runtime() and assign_cfs_rq_runtime(). Race happens when cfs_b->runtime is read, distributes without holding lock and finds out there is not enough runtime to charge against after distribution. Because assign_cfs_rq_runtime() might be called during distribution, and use cfs_b->runtime at the same time. Fibtest is the tool to test this race. Assume all gcfs_rq is throttled and cfs period timer runs, slow threads might run and sleep, returning unused cfs_rq runtime and keeping min_cfs_rq_runtime in their local pool. If all this happens sufficiently quickly, cfs_b->runtime will drop a lot. If runtime distributed is large too, over-use of runtime happens. A runtime over-using by about 70 percent of quota is seen when we test fibtest on a 96-core machine. We run fibtest with 1 fast thread and 95 slow threads in test group, configure 10ms quota for this group and see the CPU usage of fibtest is 17.0%, which is far more than the expected 10%. On a smaller machine with 32 cores, we also run fibtest with 96 threads. CPU usage is more than 12%, which is also more than expected 10%. This shows that on similar workloads, this race do affect CPU bandwidth control. Solve this by holding lock inside distribute_cfs_runtime(). Fixes: c06f04c70489 ("sched: Fix potential near-infinite distribute_cfs_runtime() loop") Reviewed-by: Ben Segall <bsegall@google.com> Signed-off-by: Huaixin Chang <changhuaixin@linux.alibaba.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/lkml/20200325092602.22471-1-changhuaixin@linux.alibaba.com/
2020-04-08sched/fair: Align rq->avg_idle and rq->avg_scan_costValentin Schneider
sched/core.c uses update_avg() for rq->avg_idle and sched/fair.c uses an open-coded version (with the exact same decay factor) for rq->avg_scan_cost. On top of that, select_idle_cpu() expects to be able to compare these two fields. The only difference between the two is that rq->avg_scan_cost is computed using a pure division rather than a shift. Turns out it actually matters, first of all because the shifted value can be negative, and the standard has this to say about it: """ The result of E1 >> E2 is E1 right-shifted E2 bit positions. [...] If E1 has a signed type and a negative value, the resulting value is implementation-defined. """ Not only this, but (arithmetic) right shifting a negative value (using 2's complement) is *not* equivalent to dividing it by the corresponding power of 2. Let's look at a few examples: -4 -> 0xF..FC -4 >> 3 -> 0xF..FF == -1 != -4 / 8 -8 -> 0xF..F8 -8 >> 3 -> 0xF..FF == -1 == -8 / 8 -9 -> 0xF..F7 -9 >> 3 -> 0xF..FE == -2 != -9 / 8 Make update_avg() use a division, and export it to the private scheduler header to reuse it where relevant. Note that this still lets compilers use a shift here, but should prevent any unwanted surprise. The disassembly of select_idle_cpu() remains unchanged on arm64, and ttwu_do_wakeup() gains 2 instructions; the diff sort of looks like this: - sub x1, x1, x0 + subs x1, x1, x0 // set condition codes + add x0, x1, #0x7 + csel x0, x0, x1, mi // x0 = x1 < 0 ? x0 : x1 add x0, x3, x0, asr #3 which does the right thing (i.e. gives us the expected result while still using an arithmetic shift) Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200330090127.16294-1-valentin.schneider@arm.com
2020-04-08perf/core: Disable page faults when getting phys addressJiri Olsa
We hit following warning when running tests on kernel compiled with CONFIG_DEBUG_ATOMIC_SLEEP=y: WARNING: CPU: 19 PID: 4472 at mm/gup.c:2381 __get_user_pages_fast+0x1a4/0x200 CPU: 19 PID: 4472 Comm: dummy Not tainted 5.6.0-rc6+ #3 RIP: 0010:__get_user_pages_fast+0x1a4/0x200 ... Call Trace: perf_prepare_sample+0xff1/0x1d90 perf_event_output_forward+0xe8/0x210 __perf_event_overflow+0x11a/0x310 __intel_pmu_pebs_event+0x657/0x850 intel_pmu_drain_pebs_nhm+0x7de/0x11d0 handle_pmi_common+0x1b2/0x650 intel_pmu_handle_irq+0x17b/0x370 perf_event_nmi_handler+0x40/0x60 nmi_handle+0x192/0x590 default_do_nmi+0x6d/0x150 do_nmi+0x2f9/0x3c0 nmi+0x8e/0xd7 While __get_user_pages_fast() is IRQ-safe, it calls access_ok(), which warns on: WARN_ON_ONCE(!in_task() && !pagefault_disabled()) Peter suggested disabling page faults around __get_user_pages_fast(), which gets rid of the warning in access_ok() call. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200407141427.3184722-1-jolsa@kernel.org
2020-04-08perf/cgroup: Correct indirection in perf_less_group_idx()Ian Rogers
The void* in perf_less_group_idx() is to a member in the array which points at a perf_event*, as such it is a perf_event**. Reported-By: John Sperbeck <jsperbeck@google.com> Fixes: 6eef8a7116de ("perf/core: Use min_heap in visit_groups_merge()") Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200321164331.107337-1-irogers@google.com
2020-04-08perf/core: Fix event cgroup trackingPeter Zijlstra
Song reports that installing cgroup events is broken since: db0503e4f675 ("perf/core: Optimize perf_install_in_event()") The problem being that cgroup events try to track cpuctx->cgrp even for disabled events, which is pointless and actively harmful since the above commit. Rework the code to have explicit enable/disable hooks for cgroup events, such that we can limit cgroup tracking to active events. More specifically, since the above commit disabled events are no longer added to their context from the 'right' CPU, and we can't access things like the current cgroup for a remote CPU. Cc: <stable@vger.kernel.org> # v5.5+ Fixes: db0503e4f675 ("perf/core: Optimize perf_install_in_event()") Reported-by: Song Liu <songliubraving@fb.com> Tested-by: Song Liu <songliubraving@fb.com> Reviewed-by: Song Liu <songliubraving@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200318193337.GB20760@hirez.programming.kicks-ass.net
2020-04-07ucount: Make sure ucounts in /proc/sys/user don't regress againJan Kara
Commit 769071ac9f20 "ns: Introduce Time Namespace" broke reporting of inotify ucounts (max_inotify_instances, max_inotify_watches) in /proc/sys/user because it has added UCOUNT_TIME_NAMESPACES into enum ucount_type but didn't properly update reporting in kernel/ucount.c:setup_userns_sysctls(). This problem got fixed in commit eeec26d5da82 "time/namespace: Add max_time_namespaces ucount". Add BUILD_BUG_ON to catch a similar problem in the future. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andrei Vagin <avagin@gmail.com> Link: https://lkml.kernel.org/r/20200407154643.10102-1-jack@suse.cz
2020-04-07kernel/gcov/fs.c: replace zero-length array with flexible-array memberGustavo A. R. Silva
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Oberparleiter <oberpar@linux.ibm.com> Link: http://lkml.kernel.org/r/20200302224851.GA26467@embeddedor Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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