- 01 Apr, 2020 1 commit
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Jason Wang authored
Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is not necessarily for VM since it's a generic userspace and kernel communication protocol. Such dependency may prevent archs without virtualization support from using vhost. To solve this, a dedicated vhost menu is created under drivers so CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION. While at it, also squash Kconfig.vringh into vhost Kconfig file. This avoids the trick of conditional inclusion from VOP or CAIF. Then it will be easier to introduce new vringh users and common dependency for both vringh and vhost. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-2-jasowang@redhat.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>
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- 23 Mar, 2020 6 commits
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David Hildenbrand authored
Commit 71994620 ("virtio_balloon: replace oom notifier with shrinker") changed the behavior when deflation happens automatically. Instead of deflating when called by the OOM handler, the shrinker is used. However, the balloon is not simply some slab cache that should be shrunk when under memory pressure. The shrinker does not have a concept of priorities, so this behavior cannot be configured. There was a report that this results in undesired side effects when inflating the balloon to shrink the page cache. [1] "When inflating the balloon against page cache (i.e. no free memory remains) vmscan.c will both shrink page cache, but also invoke the shrinkers -- including the balloon's shrinker. So the balloon driver allocates memory which requires reclaim, vmscan gets this memory by shrinking the balloon, and then the driver adds the memory back to the balloon. Basically a busy no-op." The name "deflate on OOM" makes it pretty clear when deflation should happen - after other approaches to reclaim memory failed, not while reclaiming. This allows to minimize the footprint of a guest - memory will only be taken out of the balloon when really needed. Especially, a drop_slab() will result in the whole balloon getting deflated - undesired. While handling it via the OOM handler might not be perfect, it keeps existing behavior. If we want a different behavior, then we need a new feature bit and document it properly (although, there should be a clear use case and the intended effects should be well described). Keep using the shrinker for VIRTIO_BALLOON_F_FREE_PAGE_HINT, because this has no such side effects. Always register the shrinker with VIRTIO_BALLOON_F_FREE_PAGE_HINT now. We are always allowed to reuse free pages that are still to be processed by the guest. The hypervisor takes care of identifying and resolving possible races between processing a hinting request and the guest reusing a page. In contrast to pre commit 71994620 ("virtio_balloon: replace oom notifier with shrinker"), don't add a moodule parameter to configure the number of pages to deflate on OOM. Can be re-added if really needed. Also, pay attention that leak_balloon() returns the number of 4k pages - convert it properly in virtio_balloon_oom_notify(). Note1: using the OOM handler is frowned upon, but it really is what we need for this feature. Note2: without VIRTIO_BALLOON_F_MUST_TELL_HOST (iow, always with QEMU) we could actually skip sending deflation requests to our hypervisor, making the OOM path *very* simple. Besically freeing pages and updating the balloon. If the communication with the host ever becomes a problem on this call path. [1] https://www.spinics.net/lists/linux-virtualization/msg40863.html Test report by Tyler Sanderson: Test setup: VM with 16 CPU, 64GB RAM. Running Debian 10. We have a 42 GB file full of random bytes that we continually cat to /dev/null. This fills the page cache as the file is read. Meanwhile we trigger the balloon to inflate, with a target size of 53 GB. This setup causes the balloon inflation to pressure the page cache as the page cache is also trying to grow. Afterwards we shrink the balloon back to zero (so total deflate = total inflate). Without patch (kernel 4.19.0-5): Inflation never reaches the target until we stop the "cat file > /dev/null" process. Total inflation time was 542 seconds. The longest period that made no net forward progress was 315 seconds (see attached graph). Result of "grep balloon /proc/vmstat" after the test: balloon_inflate 154828377 balloon_deflate 154828377 With patch (kernel 5.6.0-rc4+): Total inflation duration was 63 seconds. No deflate-queue activity occurs when pressuring the page-cache. Result of "grep balloon /proc/vmstat" after the test: balloon_inflate 12968539 balloon_deflate 12968539 Conclusion: This patch fixes the issue. In the test it reduced inflate/deflate activity by 12x, and reduced inflation time by 8.6x. But more importantly, if we hadn't killed the "grep balloon /proc/vmstat" process then, without the patch, the inflation process would never reach the target. Attached [1] is a png of a graph showing the problematic behavior without this patch. It shows deflate-queue activity increasing linearly while balloon size stays constant over the course of more than 8 minutes of the test. [1] https://lore.kernel.org/linux-mm/CAJuQAmphPcfew1v_EOgAdSFiprzjiZjmOf3iJDmFX0gD6b9TYQ@mail.gmail.com/2-without_patch.png Full test report and discussion [2]: [2] https://lore.kernel.org/r/CAJuQAmphPcfew1v_EOgAdSFiprzjiZjmOf3iJDmFX0gD6b9TYQ@mail.gmail.comTested-by: Tyler Sanderson <tysand@google.com> Reported-by: Tyler Sanderson <tysand@google.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Wei Wang <wei.w.wang@intel.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Nadav Amit <namit@vmware.com> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200205163402.42627-4-david@redhat.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>
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Yuri Benditovich authored
The feature VIRTIO_NET_F_HASH_REPORT extends the layout of the packet and requests the device to calculate hash on incoming packets and report it in the packet header. Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com> Link: https://lore.kernel.org/r/20200302115003.14877-4-yuri.benditovich@daynix.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>
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Yuri Benditovich authored
RSS (Receive-side scaling) defines hash calculation rules and decision on receive virtqueue according to the calculated hash, provided mask to apply and provided indirection table containing indices of receive virqueues. The driver sends the control command to enable multiqueue and provide parameters for receive steering. Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com> Link: https://lore.kernel.org/r/20200302115003.14877-3-yuri.benditovich@daynix.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>
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Yuri Benditovich authored
VIRTIO_NET_F_RSC_EXT feature bit indicates that the device is able to provide extended RSC information. When the feature is negotiatede and 'gso_type' field in received packet is not GSO_NONE, the device reports number of coalesced packets in 'csum_start' field and number of duplicated acks in 'csum_offset' field and sets VIRTIO_NET_HDR_F_RSC_INFO in 'flags' field. Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com> Link: https://lore.kernel.org/r/20200302115003.14877-2-yuri.benditovich@daynix.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>
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Michael S. Tsirkin authored
Handy for testing with distro kernels. Warn that the resulting module is completely unsupported, and isn't intended for production use. Usage: make oot # builds vhost_test.ko, vhost.ko make oot-clean # cleans out files created Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Linus Torvalds authored
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- 22 Mar, 2020 12 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linuxLinus Torvalds authored
Pull btrfs fixes from David Sterba: "Two fixes. The first is a regression: when dropping some incompat bits the conditions were reversed. The other is a fix for rename whiteout potentially leaving stack memory linked to a list" * tag 'for-5.6-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: fix removal of raid[56|1c34} incompat flags after removing block group btrfs: fix log context list corruption after rename whiteout error
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Linus Torvalds authored
Merge misc fixes from Andrew Morton: "10 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: x86/mm: split vmalloc_sync_all() mm, slub: prevent kmalloc_node crashes and memory leaks mm/mmu_notifier: silence PROVE_RCU_LIST warnings epoll: fix possible lost wakeup on epoll_ctl() path mm: do not allow MADV_PAGEOUT for CoW pages mm, memcg: throttle allocators based on ancestral memory.high mm, memcg: fix corruption on 64-bit divisor in memory.high throttling page-flags: fix a crash at SetPageError(THP_SWAP) mm/hotplug: fix hot remove failure in SPARSEMEM|!VMEMMAP case memcg: fix NULL pointer dereference in __mem_cgroup_usage_unregister_event
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Joerg Roedel authored
Commit 3f8fd02b ("mm/vmalloc: Sync unmappings in __purge_vmap_area_lazy()") introduced a call to vmalloc_sync_all() in the vunmap() code-path. While this change was necessary to maintain correctness on x86-32-pae kernels, it also adds additional cycles for architectures that don't need it. Specifically on x86-64 with CONFIG_VMAP_STACK=y some people reported severe performance regressions in micro-benchmarks because it now also calls the x86-64 implementation of vmalloc_sync_all() on vunmap(). But the vmalloc_sync_all() implementation on x86-64 is only needed for newly created mappings. To avoid the unnecessary work on x86-64 and to gain the performance back, split up vmalloc_sync_all() into two functions: * vmalloc_sync_mappings(), and * vmalloc_sync_unmappings() Most call-sites to vmalloc_sync_all() only care about new mappings being synchronized. The only exception is the new call-site added in the above mentioned commit. Shile Zhang directed us to a report of an 80% regression in reaim throughput. Fixes: 3f8fd02b ("mm/vmalloc: Sync unmappings in __purge_vmap_area_lazy()") Reported-by: kernel test robot <oliver.sang@intel.com> Reported-by: Shile Zhang <shile.zhang@linux.alibaba.com> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Borislav Petkov <bp@suse.de> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [GHES] Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20191009124418.8286-1-joro@8bytes.org Link: https://lists.01.org/hyperkitty/list/lkp@lists.01.org/thread/4D3JPPHBNOSPFK2KEPC6KGKS6J25AIDB/ Link: http://lkml.kernel.org/r/20191113095530.228959-1-shile.zhang@linux.alibaba.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
Sachin reports [1] a crash in SLUB __slab_alloc(): BUG: Kernel NULL pointer dereference on read at 0x000073b0 Faulting instruction address: 0xc0000000003d55f4 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: CPU: 19 PID: 1 Comm: systemd Not tainted 5.6.0-rc2-next-20200218-autotest #1 NIP: c0000000003d55f4 LR: c0000000003d5b94 CTR: 0000000000000000 REGS: c0000008b37836d0 TRAP: 0300 Not tainted (5.6.0-rc2-next-20200218-autotest) MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 24004844 XER: 00000000 CFAR: c00000000000dec4 DAR: 00000000000073b0 DSISR: 40000000 IRQMASK: 1 GPR00: c0000000003d5b94 c0000008b3783960 c00000000155d400 c0000008b301f500 GPR04: 0000000000000dc0 0000000000000002 c0000000003443d8 c0000008bb398620 GPR08: 00000008ba2f0000 0000000000000001 0000000000000000 0000000000000000 GPR12: 0000000024004844 c00000001ec52a00 0000000000000000 0000000000000000 GPR16: c0000008a1b20048 c000000001595898 c000000001750c18 0000000000000002 GPR20: c000000001750c28 c000000001624470 0000000fffffffe0 5deadbeef0000122 GPR24: 0000000000000001 0000000000000dc0 0000000000000002 c0000000003443d8 GPR28: c0000008b301f500 c0000008bb398620 0000000000000000 c00c000002287180 NIP ___slab_alloc+0x1f4/0x760 LR __slab_alloc+0x34/0x60 Call Trace: ___slab_alloc+0x334/0x760 (unreliable) __slab_alloc+0x34/0x60 __kmalloc_node+0x110/0x490 kvmalloc_node+0x58/0x110 mem_cgroup_css_online+0x108/0x270 online_css+0x48/0xd0 cgroup_apply_control_enable+0x2ec/0x4d0 cgroup_mkdir+0x228/0x5f0 kernfs_iop_mkdir+0x90/0xf0 vfs_mkdir+0x110/0x230 do_mkdirat+0xb0/0x1a0 system_call+0x5c/0x68 This is a PowerPC platform with following NUMA topology: available: 2 nodes (0-1) node 0 cpus: node 0 size: 0 MB node 0 free: 0 MB node 1 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 node 1 size: 35247 MB node 1 free: 30907 MB node distances: node 0 1 0: 10 40 1: 40 10 possible numa nodes: 0-31 This only happens with a mmotm patch "mm/memcontrol.c: allocate shrinker_map on appropriate NUMA node" [2] which effectively calls kmalloc_node for each possible node. SLUB however only allocates kmem_cache_node on online N_NORMAL_MEMORY nodes, and relies on node_to_mem_node to return such valid node for other nodes since commit a561ce00 ("slub: fall back to node_to_mem_node() node if allocating on memoryless node"). This is however not true in this configuration where the _node_numa_mem_ array is not initialized for nodes 0 and 2-31, thus it contains zeroes and get_partial() ends up accessing non-allocated kmem_cache_node. A related issue was reported by Bharata (originally by Ramachandran) [3] where a similar PowerPC configuration, but with mainline kernel without patch [2] ends up allocating large amounts of pages by kmalloc-1k kmalloc-512. This seems to have the same underlying issue with node_to_mem_node() not behaving as expected, and might probably also lead to an infinite loop with CONFIG_SLUB_CPU_PARTIAL [4]. This patch should fix both issues by not relying on node_to_mem_node() anymore and instead simply falling back to NUMA_NO_NODE, when kmalloc_node(node) is attempted for a node that's not online, or has no usable memory. The "usable memory" condition is also changed from node_present_pages() to N_NORMAL_MEMORY node state, as that is exactly the condition that SLUB uses to allocate kmem_cache_node structures. The check in get_partial() is removed completely, as the checks in ___slab_alloc() are now sufficient to prevent get_partial() being reached with an invalid node. [1] https://lore.kernel.org/linux-next/3381CD91-AB3D-4773-BA04-E7A072A63968@linux.vnet.ibm.com/ [2] https://lore.kernel.org/linux-mm/fff0e636-4c36-ed10-281c-8cdb0687c839@virtuozzo.com/ [3] https://lore.kernel.org/linux-mm/20200317092624.GB22538@in.ibm.com/ [4] https://lore.kernel.org/linux-mm/088b5996-faae-8a56-ef9c-5b567125ae54@suse.cz/ Fixes: a561ce00 ("slub: fall back to node_to_mem_node() node if allocating on memoryless node") Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Reported-by: PUVICHAKRAVARTHY RAMACHANDRAN <puvichakravarthy@in.ibm.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Tested-by: Bharata B Rao <bharata@linux.ibm.com> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@kernel.org> Cc: Christopher Lameter <cl@linux.com> Cc: linuxppc-dev@lists.ozlabs.org Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200320115533.9604-1-vbabka@suse.czDebugged-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Qian Cai authored
It is safe to traverse mm->notifier_subscriptions->list either under SRCU read lock or mm->notifier_subscriptions->lock using hlist_for_each_entry_rcu(). Silence the PROVE_RCU_LIST false positives, for example, WARNING: suspicious RCU usage ----------------------------- mm/mmu_notifier.c:484 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 3 locks held by libvirtd/802: #0: ffff9321e3f58148 (&mm->mmap_sem#2){++++}, at: do_mprotect_pkey+0xe1/0x3e0 #1: ffffffff91ae6160 (mmu_notifier_invalidate_range_start){+.+.}, at: change_p4d_range+0x5fa/0x800 #2: ffffffff91ae6e08 (srcu){....}, at: __mmu_notifier_invalidate_range_start+0x178/0x460 stack backtrace: CPU: 7 PID: 802 Comm: libvirtd Tainted: G I 5.6.0-rc6-next-20200317+ #2 Hardware name: HP ProLiant BL460c Gen8, BIOS I31 11/02/2014 Call Trace: dump_stack+0xa4/0xfe lockdep_rcu_suspicious+0xeb/0xf5 __mmu_notifier_invalidate_range_start+0x3ff/0x460 change_p4d_range+0x746/0x800 change_protection+0x1df/0x300 mprotect_fixup+0x245/0x3e0 do_mprotect_pkey+0x23b/0x3e0 __x64_sys_mprotect+0x51/0x70 do_syscall_64+0x91/0xae8 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Link: http://lkml.kernel.org/r/20200317175640.2047-1-cai@lca.pwSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Roman Penyaev authored
This fixes possible lost wakeup introduced by commit a218cc49. Originally modifications to ep->wq were serialized by ep->wq.lock, but in commit a218cc49 ("epoll: use rwlock in order to reduce ep_poll_callback() contention") a new rw lock was introduced in order to relax fd event path, i.e. callers of ep_poll_callback() function. After the change ep_modify and ep_insert (both are called on epoll_ctl() path) were switched to ep->lock, but ep_poll (epoll_wait) was using ep->wq.lock on wqueue list modification. The bug doesn't lead to any wqueue list corruptions, because wake up path and list modifications were serialized by ep->wq.lock internally, but actual waitqueue_active() check prior wake_up() call can be reordered with modifications of ep ready list, thus wake up can be lost. And yes, can be healed by explicit smp_mb(): list_add_tail(&epi->rdlink, &ep->rdllist); smp_mb(); if (waitqueue_active(&ep->wq)) wake_up(&ep->wp); But let's make it simple, thus current patch replaces ep->wq.lock with the ep->lock for wqueue modifications, thus wake up path always observes activeness of the wqueue correcty. Fixes: a218cc49 ("epoll: use rwlock in order to reduce ep_poll_callback() contention") Reported-by: Max Neunhoeffer <max@arangodb.com> Signed-off-by: Roman Penyaev <rpenyaev@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Max Neunhoeffer <max@arangodb.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Christopher Kohlhoff <chris.kohlhoff@clearpool.io> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: Jason Baron <jbaron@akamai.com> Cc: Jes Sorensen <jes.sorensen@gmail.com> Cc: <stable@vger.kernel.org> [5.1+] Link: http://lkml.kernel.org/r/20200214170211.561524-1-rpenyaev@suse.de References: https://bugzilla.kernel.org/show_bug.cgi?id=205933Bisected-by: Max Neunhoeffer <max@arangodb.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Michal Hocko authored
Jann has brought up a very interesting point [1]. While shared pages are excluded from MADV_PAGEOUT normally, CoW pages can be easily reclaimed that way. This can lead to all sorts of hard to debug problems. E.g. performance problems outlined by Daniel [2]. There are runtime environments where there is a substantial memory shared among security domains via CoW memory and a easy to reclaim way of that memory, which MADV_{COLD,PAGEOUT} offers, can lead to either performance degradation in for the parent process which might be more privileged or even open side channel attacks. The feasibility of the latter is not really clear to me TBH but there is no real reason for exposure at this stage. It seems there is no real use case to depend on reclaiming CoW memory via madvise at this stage so it is much easier to simply disallow it and this is what this patch does. Put it simply MADV_{PAGEOUT,COLD} can operate only on the exclusively owned memory which is a straightforward semantic. [1] http://lkml.kernel.org/r/CAG48ez0G3JkMq61gUmyQAaCq=_TwHbi1XKzWRooxZkv08PQKuw@mail.gmail.com [2] http://lkml.kernel.org/r/CAKOZueua_v8jHCpmEtTB6f3i9e2YnmX4mqdYVWhV4E=Z-n+zRQ@mail.gmail.com Fixes: 9c276cc6 ("mm: introduce MADV_COLD") Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Daniel Colascione <dancol@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: "Joel Fernandes (Google)" <joel@joelfernandes.org> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200312082248.GS23944@dhcp22.suse.czSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Chris Down authored
Prior to this commit, we only directly check the affected cgroup's memory.high against its usage. However, it's possible that we are being reclaimed as a result of hitting an ancestor memory.high and should be penalised based on that, instead. This patch changes memory.high overage throttling to use the largest overage in its ancestors when considering how many penalty jiffies to charge. This makes sure that we penalise poorly behaving cgroups in the same way regardless of at what level of the hierarchy memory.high was breached. Fixes: 0e4b01df ("mm, memcg: throttle allocators when failing reclaim over memory.high") Reported-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Chris Down <chris@chrisdown.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Tejun Heo <tj@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Nathan Chancellor <natechancellor@gmail.com> Cc: Roman Gushchin <guro@fb.com> Cc: <stable@vger.kernel.org> [5.4.x+] Link: http://lkml.kernel.org/r/8cd132f84bd7e16cdb8fde3378cdbf05ba00d387.1584036142.git.chris@chrisdown.nameSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Chris Down authored
Commit 0e4b01df had a bunch of fixups to use the right division method. However, it seems that after all that it still wasn't right -- div_u64 takes a 32-bit divisor. The headroom is still large (2^32 pages), so on mundane systems you won't hit this, but this should definitely be fixed. Fixes: 0e4b01df ("mm, memcg: throttle allocators when failing reclaim over memory.high") Reported-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Chris Down <chris@chrisdown.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <guro@fb.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Nathan Chancellor <natechancellor@gmail.com> Cc: <stable@vger.kernel.org> [5.4.x+] Link: http://lkml.kernel.org/r/80780887060514967d414b3cd91f9a316a16ab98.1584036142.git.chris@chrisdown.nameSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Qian Cai authored
Commit bd4c82c2 ("mm, THP, swap: delay splitting THP after swapped out") supported writing THP to a swap device but forgot to upgrade an older commit df8c94d1 ("page-flags: define behavior of FS/IO-related flags on compound pages") which could trigger a crash during THP swapping out with DEBUG_VM_PGFLAGS=y, kernel BUG at include/linux/page-flags.h:317! page dumped because: VM_BUG_ON_PAGE(1 && PageCompound(page)) page:fffff3b2ec3a8000 refcount:512 mapcount:0 mapping:000000009eb0338c index:0x7f6e58200 head:fffff3b2ec3a8000 order:9 compound_mapcount:0 compound_pincount:0 anon flags: 0x45fffe0000d8454(uptodate|lru|workingset|owner_priv_1|writeback|head|reclaim|swapbacked) end_swap_bio_write() SetPageError(page) VM_BUG_ON_PAGE(1 && PageCompound(page)) <IRQ> bio_endio+0x297/0x560 dec_pending+0x218/0x430 [dm_mod] clone_endio+0xe4/0x2c0 [dm_mod] bio_endio+0x297/0x560 blk_update_request+0x201/0x920 scsi_end_request+0x6b/0x4b0 scsi_io_completion+0x509/0x7e0 scsi_finish_command+0x1ed/0x2a0 scsi_softirq_done+0x1c9/0x1d0 __blk_mqnterrupt+0xf/0x20 </IRQ> Fix by checking PF_NO_TAIL in those places instead. Fixes: bd4c82c2 ("mm, THP, swap: delay splitting THP after swapped out") Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: "Huang, Ying" <ying.huang@intel.com> Acked-by: Rafael Aquini <aquini@redhat.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200310235846.1319-1-cai@lca.pwSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Baoquan He authored
In section_deactivate(), pfn_to_page() doesn't work any more after ms->section_mem_map is resetting to NULL in SPARSEMEM|!VMEMMAP case. It causes a hot remove failure: kernel BUG at mm/page_alloc.c:4806! invalid opcode: 0000 [#1] SMP PTI CPU: 3 PID: 8 Comm: kworker/u16:0 Tainted: G W 5.5.0-next-20200205+ #340 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 Workqueue: kacpi_hotplug acpi_hotplug_work_fn RIP: 0010:free_pages+0x85/0xa0 Call Trace: __remove_pages+0x99/0xc0 arch_remove_memory+0x23/0x4d try_remove_memory+0xc8/0x130 __remove_memory+0xa/0x11 acpi_memory_device_remove+0x72/0x100 acpi_bus_trim+0x55/0x90 acpi_device_hotplug+0x2eb/0x3d0 acpi_hotplug_work_fn+0x1a/0x30 process_one_work+0x1a7/0x370 worker_thread+0x30/0x380 kthread+0x112/0x130 ret_from_fork+0x35/0x40 Let's move the ->section_mem_map resetting after depopulate_section_memmap() to fix it. [akpm@linux-foundation.org: remove unneeded initialization, per David] Fixes: ba72b4c8 ("mm/sparsemem: support sub-section hotplug") Signed-off-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200307084229.28251-2-bhe@redhat.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Chunguang Xu authored
An eventfd monitors multiple memory thresholds of the cgroup, closes them, the kernel deletes all events related to this eventfd. Before all events are deleted, another eventfd monitors the memory threshold of this cgroup, leading to a crash: BUG: kernel NULL pointer dereference, address: 0000000000000004 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 800000033058e067 P4D 800000033058e067 PUD 3355ce067 PMD 0 Oops: 0002 [#1] SMP PTI CPU: 2 PID: 14012 Comm: kworker/2:6 Kdump: loaded Not tainted 5.6.0-rc4 #3 Hardware name: LENOVO 20AWS01K00/20AWS01K00, BIOS GLET70WW (2.24 ) 05/21/2014 Workqueue: events memcg_event_remove RIP: 0010:__mem_cgroup_usage_unregister_event+0xb3/0x190 RSP: 0018:ffffb47e01c4fe18 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff8bb223a8a000 RCX: 0000000000000001 RDX: 0000000000000001 RSI: ffff8bb22fb83540 RDI: 0000000000000001 RBP: ffffb47e01c4fe48 R08: 0000000000000000 R09: 0000000000000010 R10: 000000000000000c R11: 071c71c71c71c71c R12: ffff8bb226aba880 R13: ffff8bb223a8a480 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8bb242680000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000004 CR3: 000000032c29c003 CR4: 00000000001606e0 Call Trace: memcg_event_remove+0x32/0x90 process_one_work+0x172/0x380 worker_thread+0x49/0x3f0 kthread+0xf8/0x130 ret_from_fork+0x35/0x40 CR2: 0000000000000004 We can reproduce this problem in the following ways: 1. We create a new cgroup subdirectory and a new eventfd, and then we monitor multiple memory thresholds of the cgroup through this eventfd. 2. closing this eventfd, and __mem_cgroup_usage_unregister_event () will be called multiple times to delete all events related to this eventfd. The first time __mem_cgroup_usage_unregister_event() is called, the kernel will clear all items related to this eventfd in thresholds-> primary. Since there is currently only one eventfd, thresholds-> primary becomes empty, so the kernel will set thresholds-> primary and hresholds-> spare to NULL. If at this time, the user creates a new eventfd and monitor the memory threshold of this cgroup, kernel will re-initialize thresholds-> primary. Then when __mem_cgroup_usage_unregister_event () is called for the second time, because thresholds-> primary is not empty, the system will access thresholds-> spare, but thresholds-> spare is NULL, which will trigger a crash. In general, the longer it takes to delete all events related to this eventfd, the easier it is to trigger this problem. The solution is to check whether the thresholds associated with the eventfd has been cleared when deleting the event. If so, we do nothing. [akpm@linux-foundation.org: fix comment, per Kirill] Fixes: 907860ed ("cgroups: make cftype.unregister_event() void-returning") Signed-off-by: Chunguang Xu <brookxu@tencent.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/077a6f67-aefa-4591-efec-f2f3af2b0b02@gmail.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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- 21 Mar, 2020 7 commits
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git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull block fixes from Jens Axboe: "Just two NVMe fabrics fixes that should go into 5.6" * tag 'block-5.6-20200320' of git://git.kernel.dk/linux-block: nvmet-tcp: set MSG_MORE only if we actually have more to send nvme-rdma: Avoid double freeing of async event data
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git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull io_uring fixes from Jens Axboe: "Two different fixes in here: - Fix for a potential NULL pointer deref for links with async or drain marked (Pavel) - Fix for not properly checking RLIMIT_NOFILE for async punted operations. This affects openat/openat2, which were added this cycle, and accept4. I did a full audit of other cases where we might check current->signal->rlim[] and found only RLIMIT_FSIZE for buffered writes and fallocate. That one is fixed and queued for 5.7 and marked stable" * tag 'io_uring-5.6-20200320' of git://git.kernel.dk/linux-block: io_uring: make sure accept honor rlimit nofile io_uring: make sure openat/openat2 honor rlimit nofile io_uring: NULL-deref for IOSQE_{ASYNC,DRAIN}
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git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linuxLinus Torvalds authored
Pull turbostat updates from Len Brown: "Update to turbostat v20.03.20. These patches unlock the full turbostat features for some new machines, plus a couple other minor tweaks" * 'turbostat' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: tools/power turbostat: update version tools/power turbostat: Print cpuidle information tools/power turbostat: Fix 32-bit capabilities warning tools/power turbostat: Fix missing SYS_LPI counter on some Chromebooks tools/power turbostat: Support Elkhart Lake tools/power turbostat: Support Jasper Lake tools/power turbostat: Support Ice Lake server tools/power turbostat: Support Tiger Lake tools/power turbostat: Fix gcc build warnings tools/power turbostat: Support Cometlake
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linuxLinus Torvalds authored
Pull powerpc fixes from Michael Ellerman: "Two fixes for bugs introduced this cycle: - fix a crash when shutting down a KVM PR guest (our original style of KVM which doesn't use hypervisor mode) - fix for the recently added 32-bit KASAN_VMALLOC support Thanks to: Christophe Leroy, Greg Kurz, Sean Christopherson" * tag 'powerpc-5.6-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: KVM: PPC: Fix kernel crash with PR KVM powerpc/kasan: Fix shadow memory protection with CONFIG_KASAN_VMALLOC
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Len Brown authored
A stitch in time saves nine. Signed-off-by: Len Brown <len.brown@intel.com>
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Len Brown authored
Print cpuidle driver and governor. Originally-by: Antti Laakso <antti.laakso@linux.intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
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git://git.infradead.org/nvmeJens Axboe authored
Pull NVMe fixes from Keith: "Two late nvme fabrics fixes for 5.6: a double free with the rdma transport, and a regression fix for tcp; please pull." * 'nvme-5.6-rc6' of git://git.infradead.org/nvme: nvmet-tcp: set MSG_MORE only if we actually have more to send nvme-rdma: Avoid double freeing of async event data
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- 20 Mar, 2020 14 commits
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Filipe Manana authored
We are incorrectly dropping the raid56 and raid1c34 incompat flags when there are still raid56 and raid1c34 block groups, not when we do not any of those anymore. The logic just got unintentionally broken after adding the support for the raid1c34 modes. Fix this by clear the flags only if we do not have block groups with the respective profiles. Fixes: 9c907446 ("btrfs: drop incompat bit for raid1c34 after last block group is gone") Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Sagi Grimberg authored
When we send PDU data, we want to optimize the tcp stack operation if we have more data to send. So when we set MSG_MORE when: - We have more fragments coming in the batch, or - We have a more data to send in this PDU - We don't have a data digest trailer - We optimize with the SUCCESS flag and omit the NVMe completion (used if sq_head pointer update is disabled) This addresses a regression in QD=1 with SUCCESS flag optimization as we unconditionally set MSG_MORE when we didn't actually have more data to send. Fixes: 70583295 ("nvmet-tcp: implement C2HData SUCCESS optimization") Reported-by: Mark Wunderlich <mark.wunderlich@intel.com> Tested-by: Mark Wunderlich <mark.wunderlich@intel.com> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Keith Busch <kbusch@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds authored
Pull arm64 fixes from Will Deacon: - Fix panic() when it occurs during secondary CPU startup - Fix "kpti=off" when KASLR is enabled - Fix howler in compat syscall table for vDSO clock_getres() fallback * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: compat: Fix syscall number of compat_clock_getres arm64: kpti: Fix "kpti=off" when KASLR is enabled arm64: smp: fix crash_smp_send_stop() behaviour arm64: smp: fix smp_send_stop() behaviour
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-miscLinus Torvalds authored
Pull char/misc driver fixes from Greg KH: "Here are some small different driver fixes for 5.6-rc7: - binderfs fix, yet again - slimbus new device id added - hwtracing bugfixes for reported issues and a new device id All of these have been in linux-next with no reported issues" * tag 'char-misc-5.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: intel_th: pci: Add Elkhart Lake CPU support intel_th: Fix user-visible error codes intel_th: msu: Fix the unexpected state warning stm class: sys-t: Fix the use of time_after() slimbus: ngd: add v2.1.0 compatible binderfs: use refcount for binder control devices too
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/stagingLinus Torvalds authored
Pull staging/IIO fixes from Greg KH: "Here are a number of small staging and IIO driver fixes for 5.6-rc7 Nothing major here, just resolutions for some reported problems: - iio bugfixes for a number of different drivers - greybus loopback_test fixes - wfx driver fixes All of these have been in linux-next with no reported issues" * tag 'staging-5.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: staging: rtl8188eu: Add device id for MERCUSYS MW150US v2 staging: greybus: loopback_test: fix potential path truncations staging: greybus: loopback_test: fix potential path truncation staging: greybus: loopback_test: fix poll-mask build breakage staging: wfx: fix RCU usage between hif_join() and ieee80211_bss_get_ie() staging: wfx: fix RCU usage in wfx_join_finalize() staging: wfx: make warning about pending frame less scary staging: wfx: fix lines ending with a comma instead of a semicolon staging: wfx: fix warning about freeing in-use mutex during device unregister staging/speakup: fix get_word non-space look-ahead iio: ping: set pa_laser_ping_cfg in of_ping_match iio: chemical: sps30: fix missing triggered buffer dependency iio: st_sensors: remap SMO8840 to LIS2DH12 iio: light: vcnl4000: update sampling periods for vcnl4040 iio: light: vcnl4000: update sampling periods for vcnl4200 iio: accel: adxl372: Set iio_chan BE iio: magnetometer: ak8974: Fix negative raw values in sysfs iio: trigger: stm32-timer: disable master mode when stopping iio: adc: stm32-dfsdm: fix sleep in atomic context iio: adc: at91-sama5d2_adc: fix differential channels in triggered mode
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usbLinus Torvalds authored
Pull USB fixes from Greg KH: "Here are some small USB fixes for 5.6-rc7. And there's a thunderbolt driver fix thrown in for good measure as well. These fixes are: - new device ids for usb-serial drivers - thunderbolt error code fix - xhci driver fixes - typec fixes - cdc-acm driver fixes - chipidea driver fix - more USB quirks added for devices that need them. All of these have been in linux-next with no reported issues" * tag 'usb-5.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: USB: cdc-acm: fix rounding error in TIOCSSERIAL USB: cdc-acm: fix close_delay and closing_wait units in TIOCSSERIAL usb: quirks: add NO_LPM quirk for RTL8153 based ethernet adapters usb: chipidea: udc: fix sleeping function called from invalid context USB: serial: pl2303: add device-id for HP LD381 USB: serial: option: add ME910G1 ECM composition 0x110b usb: host: xhci-plat: add a shutdown usb: typec: ucsi: displayport: Fix a potential race during registration usb: typec: ucsi: displayport: Fix NULL pointer dereference USB: Disable LPM on WD19's Realtek Hub usb: xhci: apply XHCI_SUSPEND_DELAY to AMD XHCI controller 1022:145c xhci: Do not open code __print_symbolic() in xhci trace events thunderbolt: Fix error code in tb_port_is_width_supported()
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/ttyLinus Torvalds authored
Pull tty fixes from Greg KH: "Here are three small tty_io bugfixes for reported issues that Eric has resolved for 5.6-rc7 All of these have been in linux-next with no reported issues" * tag 'tty-5.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: tty: fix compat TIOCGSERIAL checking wrong function ptr tty: fix compat TIOCGSERIAL leaking uninitialized memory tty: drop outdated comments about release_tty() locking
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git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/soundLinus Torvalds authored
Pull sound fixes from Takashi Iwai: "A few fixes covering the issues reported by syzkaller, a couple of fixes for the MIDI decoding bug, and a few usual HD-audio quirks. Some of them are about ALSA core stuff, but they are small fixes just for corner cases, and nothing thrilling" * tag 'sound-5.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: ALSA: hda/realtek - Enable the headset of Acer N50-600 with ALC662 ALSA: hda/realtek - Enable headset mic of Acer X2660G with ALC662 ALSA: seq: oss: Fix running status after receiving sysex ALSA: seq: virmidi: Fix running status after receiving sysex ALSA: pcm: oss: Remove WARNING from snd_pcm_plug_alloc() checks ALSA: hda/realtek: Fix pop noise on ALC225 ALSA: line6: Fix endless MIDI read loop ALSA: pcm: oss: Avoid plugin buffer overflow
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git://anongit.freedesktop.org/drm/drmLinus Torvalds authored
Pull drm fixes from Dave Airlie: "Hope you are well hiding out above the garage. A few amdgpu changes but nothing too major. I've had a wisdom tooth out this week so haven't been to on top of things, but all seems good. core: - fix lease warning i915: - Track active elements during dequeue - Fix failure to handle all MCR ranges - Revert unnecessary workaround amdgpu: - Pageflip fix - VCN clockgating fixes - GPR debugfs fix for umr - GPU reset fix - eDP fix for MBP - DCN2.x fix dw-hdmi: - fix AVI frame colorimetry komeda: - fix compiler warning bochs: - downgrade a binding failure to a warning" * tag 'drm-fixes-2020-03-20' of git://anongit.freedesktop.org/drm/drm: drm/amd/display: Fix pageflip event race condition for DCN. drm/amdgpu: fix typo for vcn2.5/jpeg2.5 idle check drm/amdgpu: fix typo for vcn2/jpeg2 idle check drm/amdgpu: fix typo for vcn1 idle check drm/lease: fix WARNING in idr_destroy drm/i915: Handle all MCR ranges Revert "drm/i915/tgl: Add extra hdc flush workaround" drm/i915/execlists: Track active elements during dequeue drm/bochs: downgrade pci_request_region failure from error to warning drm/amd/display: Add link_rate quirk for Apple 15" MBP 2017 drm/amdgpu: add fbdev suspend/resume on gpu reset drm/amd/amdgpu: Fix GPR read from debugfs (v2) drm/amd/display: fix typos for dcn20_funcs and dcn21_funcs struct drm/komeda: mark PM functions as __maybe_unused drm/bridge: dw-hdmi: fix AVI frame colorimetry
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Jens Axboe authored
Just like commit 4022e7af, this fixes the fact that IORING_OP_ACCEPT ends up using get_unused_fd_flags(), which checks current->signal->rlim[] for limits. Add an extra argument to __sys_accept4_file() that allows us to pass in the proper nofile limit, and grab it at request prep time. Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Jens Axboe authored
Dmitry reports that a test case shows that io_uring isn't honoring a modified rlimit nofile setting. get_unused_fd_flags() checks the task signal->rlimi[] for the limits. As this isn't easily inheritable, provide a __get_unused_fd_flags() that takes the value instead. Then we can grab it when the request is prepared (from the original task), and pass that in when we do the async part part of the open. Reported-by: Dmitry Kadashev <dkadashev@gmail.com> Tested-by: Dmitry Kadashev <dkadashev@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Len Brown authored
warning: `turbostat' uses 32-bit capabilities (legacy support in use) Signed-off-by: Len Brown <len.brown@intel.com>
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Len Brown authored
Some Chromebook BIOS' do not export an ACPI LPIT, which is how Linux finds the residency counter for CPU and SYSTEM low power states, that is exports in /sys/devices/system/cpu/cpuidle/*residency_us When these sysfs attributes are missing, check the debugfs attrubte from the pmc_core driver, which accesses the same counter value. Signed-off-by: Len Brown <len.brown@intel.com>
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Chen Yu authored
From a turbostat point of view the Tremont-based Elkhart Lake is very similar to Goldmont, reuse the code of Goldmont. Elkhart Lake does not support 'group turbo limit counter' nor C3, adjust the code accordingly. Signed-off-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
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