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CEPH_OSDMAP_FULL/NEARFULL aren't set since mimic, so we need to consult
per-pool flags as well. Unfortunately the backwards compatibility here
is lacking:
- the change that deprecated OSDMAP_FULL/NEARFULL went into mimic, but
was guarded by require_osd_release >= RELEASE_LUMINOUS
- it was subsequently backported to luminous in v12.2.2, but that makes
no difference to clients that only check OSDMAP_FULL/NEARFULL because
require_osd_release is not client-facing -- it is for OSDs
Since all kernels are affected, the best we can do here is just start
checking both map flags and pool flags and send that to stable.
These checks are best effort, so take osdc->lock and look up pool flags
just once. Remove the FIXME, since filesystem quotas are checked above
and RADOS quotas are reflected in POOL_FLAG_FULL: when the pool reaches
its quota, both POOL_FLAG_FULL and POOL_FLAG_FULL_QUOTA are set.
Cc: stable@vger.kernel.org
Reported-by: Yanhu Cao <gmayyyha@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Sage Weil <sage@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
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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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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Commit 3f8fd02b1bf1 ("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: 3f8fd02b1bf1 ("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.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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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
a561ce00b09e ("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: a561ce00b09e ("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.cz
Debugged-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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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.pw
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This fixes possible lost wakeup introduced by commit a218cc491420.
Originally modifications to ep->wq were serialized by ep->wq.lock, but
in commit a218cc491420 ("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: a218cc491420 ("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=205933
Bisected-by: Max Neunhoeffer <max@arangodb.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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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: 9c276cc65a58 ("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.cz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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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: 0e4b01df8659 ("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.name
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Commit 0e4b01df8659 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: 0e4b01df8659 ("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.name
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Commit bd4c82c22c36 ("mm, THP, swap: delay splitting THP after swapped
out") supported writing THP to a swap device but forgot to upgrade an
older commit df8c94d13c7e ("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: bd4c82c22c36 ("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.pw
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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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: ba72b4c8cf60 ("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.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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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: 907860ed381a ("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.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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|
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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|
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/linux
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/linux
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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A stitch in time saves nine.
Signed-off-by: Len Brown <len.brown@intel.com>
|
|
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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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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|
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: 9c907446dce3 ("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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|
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: 70583295388a ("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/linux
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-misc
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/staging
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/usb
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/tty
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/sound
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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|
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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Just like commit 4022e7af86be, 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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|
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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|
warning: `turbostat' uses 32-bit capabilities (legacy support in use)
Signed-off-by: Len Brown <len.brown@intel.com>
|
|
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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|
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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Jasper Lake, like Elkhart Lake, uses a Tremont CPU.
So reuse the code.
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
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|
From a turbostat point of view, Ice Lake server looks like Sky Lake server.
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
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|
From a turbostat point of view, Tiger Lake looks like Ice Lake.
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
|
|
Warning: ‘__builtin_strncpy’ specified bound 20 equals destination size
[-Wstringop-truncation]
reduce param to strncpy, to guarantee that a null byte is always copied
into destination buffer.
Signed-off-by: Len Brown <len.brown@intel.com>
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|
From a turbostat point of view, Cometlake is like Kabylake.
Suggested-by: Rui Zhang <rui.zhang@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
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git://anongit.freedesktop.org/drm/drm-intel into drm-fixes
drm/i915 fixes for v5.6-rc7:
- Track active elements during dequeue
- Fix failure to handle all MCR ranges
- Revert unnecessary workaround
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/877dzgepvu.fsf@intel.com
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git://people.freedesktop.org/~agd5f/linux into drm-fixes
amd-drm-fixes-5.6-2020-03-19:
amdgpu:
- Pageflip fix
- VCN clockgating fixes
- GPR debugfs fix for umr
- GPU reset fix
- eDP fix for MBP
- DCN2.x fix
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200319204054.1036478-1-alexander.deucher@amd.com
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With PR KVM, shutting down a VM causes the host kernel to crash:
[ 314.219284] BUG: Unable to handle kernel data access on read at 0xc00800000176c638
[ 314.219299] Faulting instruction address: 0xc008000000d4ddb0
cpu 0x0: Vector: 300 (Data Access) at [c00000036da077a0]
pc: c008000000d4ddb0: kvmppc_mmu_pte_flush_all+0x68/0xd0 [kvm_pr]
lr: c008000000d4dd94: kvmppc_mmu_pte_flush_all+0x4c/0xd0 [kvm_pr]
sp: c00000036da07a30
msr: 900000010280b033
dar: c00800000176c638
dsisr: 40000000
current = 0xc00000036d4c0000
paca = 0xc000000001a00000 irqmask: 0x03 irq_happened: 0x01
pid = 1992, comm = qemu-system-ppc
Linux version 5.6.0-master-gku+ (greg@palmb) (gcc version 7.5.0 (Ubuntu 7.5.0-3ubuntu1~18.04)) #17 SMP Wed Mar 18 13:49:29 CET 2020
enter ? for help
[c00000036da07ab0] c008000000d4fbe0 kvmppc_mmu_destroy_pr+0x28/0x60 [kvm_pr]
[c00000036da07ae0] c0080000009eab8c kvmppc_mmu_destroy+0x34/0x50 [kvm]
[c00000036da07b00] c0080000009e50c0 kvm_arch_vcpu_destroy+0x108/0x140 [kvm]
[c00000036da07b30] c0080000009d1b50 kvm_vcpu_destroy+0x28/0x80 [kvm]
[c00000036da07b60] c0080000009e4434 kvm_arch_destroy_vm+0xbc/0x190 [kvm]
[c00000036da07ba0] c0080000009d9c2c kvm_put_kvm+0x1d4/0x3f0 [kvm]
[c00000036da07c00] c0080000009da760 kvm_vm_release+0x38/0x60 [kvm]
[c00000036da07c30] c000000000420be0 __fput+0xe0/0x310
[c00000036da07c90] c0000000001747a0 task_work_run+0x150/0x1c0
[c00000036da07cf0] c00000000014896c do_exit+0x44c/0xd00
[c00000036da07dc0] c0000000001492f4 do_group_exit+0x64/0xd0
[c00000036da07e00] c000000000149384 sys_exit_group+0x24/0x30
[c00000036da07e20] c00000000000b9d0 system_call+0x5c/0x68
This is caused by a use-after-free in kvmppc_mmu_pte_flush_all()
which dereferences vcpu->arch.book3s which was previously freed by
kvmppc_core_vcpu_free_pr(). This happens because kvmppc_mmu_destroy()
is called after kvmppc_core_vcpu_free() since commit ff030fdf5573
("KVM: PPC: Move kvm_vcpu_init() invocation to common code").
The kvmppc_mmu_destroy() helper calls one of the following depending
on the KVM backend:
- kvmppc_mmu_destroy_hv() which does nothing (Book3s HV)
- kvmppc_mmu_destroy_pr() which undoes the effects of
kvmppc_mmu_init() (Book3s PR 32-bit)
- kvmppc_mmu_destroy_pr() which undoes the effects of
kvmppc_mmu_init() (Book3s PR 64-bit)
- kvmppc_mmu_destroy_e500() which does nothing (BookE e500/e500mc)
It turns out that this is only relevant to PR KVM actually. And both
32 and 64 backends need vcpu->arch.book3s to be valid when calling
kvmppc_mmu_destroy_pr(). So instead of calling kvmppc_mmu_destroy()
from kvm_arch_vcpu_destroy(), call kvmppc_mmu_destroy_pr() at the
beginning of kvmppc_core_vcpu_free_pr(). This is consistent with
kvmppc_mmu_init() being the last call in kvmppc_core_vcpu_create_pr().
For the same reason, if kvmppc_core_vcpu_create_pr() returns an
error then this means that kvmppc_mmu_init() was either not called
or failed, in which case kvmppc_mmu_destroy() should not be called.
Drop the line in the error path of kvm_arch_vcpu_create().
Fixes: ff030fdf5573 ("KVM: PPC: Move kvm_vcpu_init() invocation to common code")
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/158455341029.178873.15248663726399374882.stgit@bahia.lan
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|
Commit '16f17eda8bad ("drm/amd/display: Send vblank and user
events at vsartup for DCN")' introduces a new way of pageflip
completion handling for DCN, and some trouble.
The current implementation introduces a race condition, which
can cause pageflip completion events to be sent out one vblank
too early, thereby confusing userspace and causing flicker:
prepare_flip_isr():
1. Pageflip programming takes the ddev->event_lock.
2. Sets acrtc->pflip_status == AMDGPU_FLIP_SUBMITTED
3. Releases ddev->event_lock.
--> Deadline for surface address regs double-buffering passes on
target pipe.
4. dc_commit_updates_for_stream() MMIO programs the new pageflip
into hw, but too late for current vblank.
=> pflip_status == AMDGPU_FLIP_SUBMITTED, but flip won't complete
in current vblank due to missing the double-buffering deadline
by a tiny bit.
5. VSTARTUP trigger point in vblank is reached, VSTARTUP irq fires,
dm_dcn_crtc_high_irq() gets called.
6. Detects pflip_status == AMDGPU_FLIP_SUBMITTED and assumes the
pageflip has been completed/will complete in this vblank and
sends out pageflip completion event to userspace and resets
pflip_status = AMDGPU_FLIP_NONE.
=> Flip completion event sent out one vblank too early.
This behaviour has been observed during my testing with measurement
hardware a couple of time.
The commit message says that the extra flip event code was added to
dm_dcn_crtc_high_irq() to prevent missing to send out pageflip events
in case the pflip irq doesn't fire, because the "DCH HUBP" component
is clock gated and doesn't fire pflip irqs in that state. Also that
this clock gating may happen if no planes are active. This suggests
that the problem addressed by that commit can't happen if planes
are active.
The proposed solution is therefore to only execute the extra pflip
completion code iff the count of active planes is zero and otherwise
leave pflip completion handling to the pflip irq handler, for a
more race-free experience.
Note that i don't know if this fixes the problem the original commit
tried to address, as i don't know what the test scenario was. It
does fix the observed too early pageflip events though and points
out the problem introduced.
Fixes: 16f17eda8bad ("drm/amd/display: Send vblank and user events at vsartup for DCN")
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc
Pull MMC fixes from Ulf Hansson:
- rtsx_pci: Fix support for some various speed modes
- sdhci-of-at91: Fix support for GPIO card detect on SAMA5D2
- sdhci-cadence: Fix support for DDR52 speed mode for eMMC on UniPhier
- sdhci-acpi: Fix broken WP support on Acer Aspire Switch 10
- sdhci-acpi: Workaround FW bug for suspend on Lenovo Miix 320
* tag 'mmc-v5.6-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
mmc: rtsx_pci: Fix support for speed-modes that relies on tuning
mmc: sdhci-of-at91: fix cd-gpios for SAMA5D2
mmc: sdhci-cadence: set SDHCI_QUIRK2_PRESET_VALUE_BROKEN for UniPhier
mmc: sdhci-acpi: Disable write protect detection on Acer Aspire Switch 10 (SW5-012)
mmc: sdhci-acpi: Switch signal voltage back to 3.3V on suspend on external microSD on Lenovo Miix 320
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The syscall number of compat_clock_getres was erroneously set to 247
(__NR_io_cancel!) instead of 264. This causes the vDSO fallback of
clock_getres() to land on the wrong syscall for compat tasks.
Fix the numbering.
Cc: <stable@vger.k |
