Pull ceph fixes from Ilya Dryomov:
"Two important filesystem fixes, marked for stable.
The blocklisted superblocks issue was particularly annoying because
for unexperienced users it essentially exacted a reboot to establish a
new functional mount in that scenario"
* tag 'ceph-for-5.15-rc7' of git://github.com/ceph/ceph-client:
ceph: fix handling of "meta" errors
ceph: skip existing superblocks that are blocklisted or shut down when mounting
Pull dma-mapping fixes from Christoph Hellwig:
- fix more dma-debug fallout (Gerald Schaefer, Hamza Mahfooz)
- fix a kerneldoc warning (Logan Gunthorpe)
* tag 'dma-mapping-5.15-2' of git://git.infradead.org/users/hch/dma-mapping:
dma-debug: teach add_dma_entry() about DMA_ATTR_SKIP_CPU_SYNC
dma-debug: fix sg checks in debug_dma_map_sg()
dma-mapping: fix the kerneldoc for dma_map_sgtable()
Pull sound fixes from Takashi Iwai:
"Again it became bigger than wished, unfortunately, as this contains
quite a few ASoC fixes that came up a bit late. It also includes yet
more HD- and USB-audio quirks: I decided to merge them now, as those
are for stable, and we'll need them sooner or later.
Although the volumes are a bit high, all changes are device-specific
(and reasonably small) fixes, so it should be safe for the late rc"
* tag 'sound-5.15-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: usb-audio: Fix microphone sound on Jieli webcam.
ALSA: hda/realtek: Fixes HP Spectre x360 15-eb1xxx speakers
ALSA: usb-audio: Provide quirk for Sennheiser GSP670 Headset
ALSA: hda/realtek: Add quirk for Clevo PC50HS
ALSA: usb-audio: add Schiit Hel device to quirk table
ASoC: wm8960: Fix clock configuration on slave mode
ASoC: cs42l42: Ensure 0dB full scale volume is used for headsets
ASoC: soc-core: fix null-ptr-deref in snd_soc_del_component_unlocked()
ASoC: codec: wcd938x: Add irq config support
ASoC: DAPM: Fix missing kctl change notifications
ASoC: Intel: bytcht_es8316: Utilize dev_err_probe() to avoid log saturation
ASoC: Intel: bytcht_es8316: Switch to use gpiod_get_optional()
ASoC: Intel: bytcht_es8316: Use temporary variable for struct device
ASoC: Intel: bytcht_es8316: Get platform data via dev_get_platdata()
ASoC: wcd938x: Fix jack detection issue
ASoC: nau8824: Fix headphone vs headset, button-press detection no longer working
ASoC: cs4341: Add SPI device ID table
ASoC: pcm179x: Add missing entries SPI to device ID table
ASoC: fsl_xcvr: Fix channel swap issue with ARC
ASoC: pcm512x: Mend accesses to the I2S_1 and I2S_2 registers
Pull audit fix from Paul Moore:
"One small audit patch to add a pointer NULL check"
* tag 'audit-pr-20211019' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: fix possible null-pointer dereference in audit_filter_rules
Pull tracing fix from Steven Rostedt:
"Recursion fix for tracing.
While cleaning up some of the tracing recursion protection logic, I
discovered a scenario that the current design would miss, and would
allow an infinite recursion. Removing an optimization trick that
opened the hole fixes the issue and cleans up the code as well"
* tag 'trace-v5.15-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Have all levels of checks prevent recursion
Pull nios2 fix from Dinh Nguyen:
- Renamed CTL_STATUS to CTL_FSTATUS to fix a redefined warning
* tag 'nios2_fixes_for_v5.15_part2' of git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux:
NIOS2: irqflags: rename a redefined register name
Pull kvm fixes from Paolo Bonzini:
"Tools:
- kvm_stat: do not show halt_wait_ns since it is not a cumulative statistic
x86:
- clean ups and fixes for bus lock vmexit and lazy allocation of rmaps
- two fixes for SEV-ES (one more coming as soon as I get reviews)
- fix for static_key underflow
ARM:
- Properly refcount pages used as a concatenated stage-2 PGD
- Fix missing unlock when detecting the use of MTE+VM_SHARED"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: SEV-ES: reduce ghcb_sa_len to 32 bits
KVM: VMX: Remove redundant handling of bus lock vmexit
KVM: kvm_stat: do not show halt_wait_ns
KVM: x86: WARN if APIC HW/SW disable static keys are non-zero on unload
Revert "KVM: x86: Open code necessary bits of kvm_lapic_set_base() at vCPU RESET"
KVM: SEV-ES: Set guest_state_protected after VMSA update
KVM: X86: fix lazy allocation of rmaps
KVM: SEV-ES: fix length of string I/O
KVM: arm64: Release mmap_lock when using VM_SHARED with MTE
KVM: arm64: Report corrupted refcount at EL2
KVM: arm64: Fix host stage-2 PGD refcount
KVM: s390: Function documentation fixes
Merge misc fixes from Andrew Morton:
"19 patches.
Subsystems affected by this patch series: mm (userfaultfd, migration,
memblock, mempolicy, slub, secretmem, and thp), ocfs2, binfmt, vfs,
and misc"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mailmap: add Andrej Shadura
mm/thp: decrease nr_thps in file's mapping on THP split
mm/secretmem: fix NULL page->mapping dereference in page_is_secretmem()
vfs: check fd has read access in kernel_read_file_from_fd()
elfcore: correct reference to CONFIG_UML
mm, slub: fix incorrect memcg slab count for bulk free
mm, slub: fix potential use-after-free in slab_debugfs_fops
mm, slub: fix potential memoryleak in kmem_cache_open()
mm, slub: fix mismatch between reconstructed freelist depth and cnt
mm, slub: fix two bugs in slab_debug_trace_open()
mm/mempolicy: do not allow illegal MPOL_F_NUMA_BALANCING | MPOL_LOCAL in mbind()
memblock: check memory total_size
ocfs2: mount fails with buffer overflow in strlen
ocfs2: fix data corruption after conversion from inline format
mm/migrate: fix CPUHP state to update node demotion order
mm/migrate: add CPU hotplug to demotion #ifdef
mm/migrate: optimize hotplug-time demotion order updates
userfaultfd: fix a race between writeprotect and exit_mmap()
mm/userfaultfd: selftests: fix memory corruption with thp enabled
Currently, we check the wb_err too early for directories, before all of
the unsafe child requests have been waited on. In order to fix that we
need to check the mapping->wb_err later nearer to the end of ceph_fsync.
We also have an overly-complex method for tracking errors after
blocklisting. The errors recorded in cleanup_session_requests go to a
completely separate field in the inode, but we end up reporting them the
same way we would for any other error (in fsync).
There's no real benefit to tracking these errors in two different
places, since the only reporting mechanism for them is in fsync, and
we'd need to advance them both every time.
Given that, we can just remove i_meta_err, and convert the places that
used it to instead just use mapping->wb_err instead. That also fixes
the original problem by ensuring that we do a check_and_advance of the
wb_err at the end of the fsync op.
Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/52864
Reported-by: Patrick Donnelly <pdonnell@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Currently when mounting, we may end up finding an existing superblock
that corresponds to a blocklisted MDS client. This means that the new
mount ends up being unusable.
If we've found an existing superblock with a client that is already
blocklisted, and the client is not configured to recover on its own,
fail the match. Ditto if the superblock has been forcibly unmounted.
While we're in here, also rename "other" to the more conventional "fsc".
Cc: stable@vger.kernel.org
URL: https://bugzilla.redhat.com/show_bug.cgi?id=1901499
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Starting with kernel 5.11 built with CONFIG_FORTIFY_SOURCE mouting an
ocfs2 filesystem with either o2cb or pcmk cluster stack fails with the
trace below. Problem seems to be that strings for cluster stack and
cluster name are not guaranteed to be null terminated in the disk
representation, while strlcpy assumes that the source string is always
null terminated. This causes a read outside of the source string
triggering the buffer overflow detection.
detected buffer overflow in strlen
------------[ cut here ]------------
kernel BUG at lib/string.c:1149!
invalid opcode: 0000 [#1] SMP PTI
CPU: 1 PID: 910 Comm: mount.ocfs2 Not tainted 5.14.0-1-amd64 #1
Debian 5.14.6-2
RIP: 0010:fortify_panic+0xf/0x11
...
Call Trace:
ocfs2_initialize_super.isra.0.cold+0xc/0x18 [ocfs2]
ocfs2_fill_super+0x359/0x19b0 [ocfs2]
mount_bdev+0x185/0x1b0
legacy_get_tree+0x27/0x40
vfs_get_tree+0x25/0xb0
path_mount+0x454/0xa20
__x64_sys_mount+0x103/0x140
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
Link: https://lkml.kernel.org/r/20210929180654.32460-1-vvidic@valentin-vidic.from.hr
Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 6dbf7bb555 ("fs: Don't invalidate page buffers in
block_write_full_page()") uncovered a latent bug in ocfs2 conversion
from inline inode format to a normal inode format.
The code in ocfs2_convert_inline_data_to_extents() attempts to zero out
the whole cluster allocated for file data by grabbing, zeroing, and
dirtying all pages covering this cluster. However these pages are
beyond i_size, thus writeback code generally ignores these dirty pages
and no blocks were ever actually zeroed on the disk.
This oversight was fixed by commit 693c241a5f ("ocfs2: No need to zero
pages past i_size.") for standard ocfs2 write path, inline conversion
path was apparently forgotten; the commit log also has a reasoning why
the zeroing actually is not needed.
After commit 6dbf7bb555, things became worse as writeback code stopped
invalidating buffers on pages beyond i_size and thus these pages end up
with clean PageDirty bit but with buffers attached to these pages being
still dirty. So when a file is converted from inline format, then
writeback triggers, and then the file is grown so that these pages
become valid, the invalid dirtiness state is preserved,
mark_buffer_dirty() does nothing on these pages (buffers are already
dirty) but page is never written back because it is clean. So data
written to these pages is lost once pages are reclaimed.
Simple reproducer for the problem is:
xfs_io -f -c "pwrite 0 2000" -c "pwrite 2000 2000" -c "fsync" \
-c "pwrite 4000 2000" ocfs2_file
After unmounting and mounting the fs again, you can observe that end of
'ocfs2_file' has lost its contents.
Fix the problem by not doing the pointless zeroing during conversion
from inline format similarly as in the standard write path.
[akpm@linux-foundation.org: fix whitespace, per Joseph]
Link: https://lkml.kernel.org/r/20210930095405.21433-1-jack@suse.cz
Fixes: 6dbf7bb555 ("fs: Don't invalidate page buffers in block_write_full_page()")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Tested-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Acked-by: Gang He <ghe@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: "Markov, Andrey" <Markov.Andrey@Dell.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The node demotion order needs to be updated during CPU hotplug. Because
whether a NUMA node has CPU may influence the demotion order. The
update function should be called during CPU online/offline after the
node_states[N_CPU] has been updated. That is done in
CPUHP_AP_ONLINE_DYN during CPU online and in CPUHP_MM_VMSTAT_DEAD during
CPU offline. But in commit 884a6e5d1f ("mm/migrate: update node
demotion order on hotplug events"), the function to update node demotion
order is called in CPUHP_AP_ONLINE_DYN during CPU online/offline. This
doesn't satisfy the order requirement.
For example, there are 4 CPUs (P0, P1, P2, P3) in 2 sockets (P0, P1 in S0
and P2, P3 in S1), the demotion order is
- S0 -> NUMA_NO_NODE
- S1 -> NUMA_NO_NODE
After P2 and P3 is offlined, because S1 has no CPU now, the demotion
order should have been changed to
- S0 -> S1
- S1 -> NO_NODE
but it isn't changed, because the order updating callback for CPU
hotplug doesn't see the new nodemask. After that, if P1 is offlined,
the demotion order is changed to the expected order as above.
So in this patch, we added CPUHP_AP_MM_DEMOTION_ONLINE and
CPUHP_MM_DEMOTION_DEAD to be called after CPUHP_AP_ONLINE_DYN and
CPUHP_MM_VMSTAT_DEAD during CPU online and offline, and register the
update function on them.
Link: https://lkml.kernel.org/r/20210929060351.7293-1-ying.huang@intel.com
Fixes: 884a6e5d1f ("mm/migrate: update node demotion order on hotplug events")
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm/migrate: 5.15 fixes for automatic demotion", v2.
This contains two fixes for the "automatic demotion" code which was
merged into 5.15:
* Fix memory hotplug performance regression by watching
suppressing any real action on irrelevant hotplug events.
* Ensure CPU hotplug handler is registered when memory hotplug
is disabled.
This patch (of 2):
== tl;dr ==
Automatic demotion opted for a simple, lazy approach to handling hotplug
events. This noticeably slows down memory hotplug[1]. Optimize away
updates to the demotion order when memory hotplug events should have no
effect.
This has no effect on CPU hotplug. There is no known problem on the CPU
side and any work there will be in a separate series.
== Background ==
Automatic demotion is a memory migration strategy to ensure that new
allocations have room in faster memory tiers on tiered memory systems.
The kernel maintains an array (node_demotion[]) to drive these
migrations.
The node_demotion[] path is calculated by starting at nodes with CPUs
and then "walking" to nodes with memory. Only hotplug events which
online or offline a node with memory (N_ONLINE) or CPUs (N_CPU) will
actually affect the migration order.
== Problem ==
However, the current code is lazy. It completely regenerates the
migration order on *any* CPU or memory hotplug event. The logic was
that these events are extremely rare and that the overhead from
indiscriminate order regeneration is minimal.
Part of the update logic involves a synchronize_rcu(), which is a pretty
big hammer. Its overhead was large enough to be detected by some 0day
tests that watch memory hotplug performance[1].
== Solution ==
Add a new helper (node_demotion_topo_changed()) which can differentiate
between superfluous and impactful hotplug events. Skip the expensive
update operation for superfluous events.
== Aside: Locking ==
It took me a few moments to declare the locking to be safe enough for
node_demotion_topo_changed() to work. It all hinges on the memory
hotplug lock:
During memory hotplug events, 'mem_hotplug_lock' is held for write.
This ensures that two memory hotplug events can not be called
simultaneously.
CPU hotplug has a similar lock (cpuhp_state_mutex) which also provides
mutual exclusion between CPU hotplug events. In addition, the demotion
code acquire and hold the mem_hotplug_lock for read during its CPU
hotplug handlers. This provides mutual exclusion between the demotion
memory hotplug callbacks and the CPU hotplug callbacks.
This effectively allows treating the migration target generation code to
act as if it is single-threaded.
1. https://lore.kernel.org/all/20210905135932.GE15026@xsang-OptiPlex-9020/
Link: https://lkml.kernel.org/r/20210924161251.093CCD06@davehans-spike.ostc.intel.com
Link: https://lkml.kernel.org/r/20210924161253.D7673E31@davehans-spike.ostc.intel.com
Fixes: 884a6e5d1f ("mm/migrate: update node demotion order on hotplug events")
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In RHEL's gating selftests we've encountered memory corruption in the
uffd event test even with upstream kernel:
# ./userfaultfd anon 128 4
nr_pages: 32768, nr_pages_per_cpu: 32768
bounces: 3, mode: rnd racing read, userfaults: 6240 missing (6240) 14729 wp (14729)
bounces: 2, mode: racing read, userfaults: 1444 missing (1444) 28877 wp (28877)
bounces: 1, mode: rnd read, userfaults: 6055 missing (6055) 14699 wp (14699)
bounces: 0, mode: read, userfaults: 82 missing (82) 25196 wp (25196)
testing uffd-wp with pagemap (pgsize=4096): done
testing uffd-wp with pagemap (pgsize=2097152): done
testing events (fork, remap, remove): ERROR: nr 32427 memory corruption 0 1 (errno=0, line=963)
ERROR: faulting process failed (errno=0, line=1117)
It can be easily reproduced when global thp enabled, which is the
default for RHEL.
It's also known as a side effect of commit 0db282ba2c ("selftest: use
mmap instead of posix_memalign to allocate memory", 2021-07-23), which
is imho right itself on using mmap() to make sure the addresses will be
untagged even on arm.
The problem is, for each test we allocate buffers using two
allocate_area() calls. We assumed these two buffers won't affect each
other, however they could, because mmap() could have found that the two
buffers are near each other and having the same VMA flags, so they got
merged into one VMA.
It won't be a big problem if thp is not enabled, but when thp is
agressively enabled it means when initializing the src buffer it could
accidentally setup part of the dest buffer too when there's a shared THP
that overlaps the two regions. Then some of the dest buffer won't be
able to be trapped by userfaultfd missing mode, then it'll cause memory
corruption as described.
To fix it, do release_pages() after initializing the src buffer.
Since the previous two release_pages() calls are after
uffd_test_ctx_clear() which will unmap all the buffers anyway (which is
stronger than release pages; as unmap() also tear town pgtables), drop
them as they shouldn't really be anything useful.
We can mark the Fixes tag upon 0db282ba2c as it's reported to only
happen there, however the real "Fixes" IMHO should be 8ba6e86408, as
before that commit we'll always do explicit release_pages() before
registration of uffd, and 8ba6e86408 changed that logic by adding
extra unmap/map and we didn't release the pages at the right place.
Meanwhile I don't have a solid glue anyway on whether posix_memalign()
could always avoid triggering this bug, hence it's safer to attach this
fix to commit 8ba6e86408.
Link: https://lkml.kernel.org/r/20210923232512.210092-1-peterx@redhat.com
Fixes: 8ba6e86408 ("userfaultfd/selftests: reinitialize test context in each test")
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1994931
Signed-off-by: Peter Xu <peterx@redhat.com>
Reported-by: Li Wang <liwan@redhat.com>
Tested-by: Li Wang <liwang@redhat.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When a Jieli Technology USB Webcam is connected, the video part works
well, but the mic sound is speeded up. On dmesg there are messages
about different rates from the runtime rates, warnings about volume
resolution and lastly, the log is filled, every 5 seconds, with
retire_capture_urb error messages.
The mic works only when ep packet size is set to wMaxPacketSize (normal
sound and no more retire_capture_urb error messages). Skipping reading
sample rate, fixes the messages about different rates and forcing a volume
resolution, fixes warnings about volume range. I have arbitrarily choosed
the value (16): I read in a comment that there should be no more than 255
levels, so 4096 (max volume) / 16 = 0-255.
Signed-off-by: Marco Giunta <giun7a@gmail.com>
Link: https://lore.kernel.org/r/20211018162552.12082-1-giun7a@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
While writing an email explaining the "bit = 0" logic for a discussion on
making ftrace_test_recursion_trylock() disable preemption, I discovered a
path that makes the "not do the logic if bit is zero" unsafe.
The recursion logic is done in hot paths like the function tracer. Thus,
any code executed causes noticeable overhead. Thus, tricks are done to try
to limit the amount of code executed. This included the recursion testing
logic.
Having recursion testing is important, as there are many paths that can
end up in an infinite recursion cycle when tracing every function in the
kernel. Thus protection is needed to prevent that from happening.
Because it is OK to recurse due to different running context levels (e.g.
an interrupt preempts a trace, and then a trace occurs in the interrupt
handler), a set of bits are used to know which context one is in (normal,
softirq, irq and NMI). If a recursion occurs in the same level, it is
prevented*.
Then there are infrastructure levels of recursion as well. When more than
one callback is attached to the same function to trace, it calls a loop
function to iterate over all the callbacks. Both the callbacks and the
loop function have recursion protection. The callbacks use the
"ftrace_test_recursion_trylock()" which has a "function" set of context
bits to test, and the loop function calls the internal
trace_test_and_set_recursion() directly, with an "internal" set of bits.
If an architecture does not implement all the features supported by ftrace
then the callbacks are never called directly, and the loop function is
called instead, which will implement the features of ftrace.
Since both the loop function and the callbacks do recursion protection, it
was seemed unnecessary to do it in both locations. Thus, a trick was made
to have the internal set of recursion bits at a more significant bit
location than the function bits. Then, if any of the higher bits were set,
the logic of the function bits could be skipped, as any new recursion
would first have to go through the loop function.
This is true for architectures that do not support all the ftrace
features, because all functions being traced must first go through the
loop function before going to the callbacks. But this is not true for
architectures that support all the ftrace features. That's because the
loop function could be called due to two callbacks attached to the same
function, but then a recursion function inside the callback could be
called that does not share any other callback, and it will be called
directly.
i.e.
traced_function_1: [ more than one callback tracing it ]
call loop_func
loop_func:
trace_recursion set internal bit
call callback
callback:
trace_recursion [ skipped because internal bit is set, return 0 ]
call traced_function_2
traced_function_2: [ only traced by above callback ]
call callback
callback:
trace_recursion [ skipped because internal bit is set, return 0 ]
call traced_function_2
[ wash, rinse, repeat, BOOM! out of shampoo! ]
Thus, the "bit == 0 skip" trick is not safe, unless the loop function is
call for all functions.
Since we want to encourage architectures to implement all ftrace features,
having them slow down due to this extra logic may encourage the
maintainers to update to the latest ftrace features. And because this
logic is only safe for them, remove it completely.
[*] There is on layer of recursion that is allowed, and that is to allow
for the transition between interrupt context (normal -> softirq ->
irq -> NMI), because a trace may occur before the context update is
visible to the trace recursion logic.
Link: https://lore.kernel.org/all/609b565a-ed6e-a1da-f025-166691b5d994@linux.alibaba.com/
Link: https://lkml.kernel.org/r/20211018154412.09fcad3c@gandalf.local.home
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@hansenpartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Jisheng Zhang <jszhang@kernel.org>
Cc: =?utf-8?b?546L6LSH?= <yun.wang@linux.alibaba.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: stable@vger.kernel.org
Fixes: edc15cafcb ("tracing: Avoid unnecessary multiple recursion checks")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The size of the GHCB scratch area is limited to 16 KiB (GHCB_SCRATCH_AREA_LIMIT),
so there is no need for it to be a u64. This fixes a build error on 32-bit
systems:
i686-linux-gnu-ld: arch/x86/kvm/svm/sev.o: in function `sev_es_string_io:
sev.c:(.text+0x110f): undefined reference to `__udivdi3'
Cc: stable@vger.kernel.org
Fixes: 019057bd73 ("KVM: SEV-ES: fix length of string I/O")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Hardware may or may not set exit_reason.bus_lock_detected on BUS_LOCK
VM-Exits. Dealing with KVM_RUN_X86_BUS_LOCK in handle_bus_lock_vmexit
could be redundant when exit_reason.basic is EXIT_REASON_BUS_LOCK.
We can remove redundant handling of bus lock vmexit. Unconditionally Set
exit_reason.bus_lock_detected in handle_bus_lock_vmexit(), and deal with
KVM_RUN_X86_BUS_LOCK only in vmx_handle_exit().
Signed-off-by: Hao Xiang <hao.xiang@linux.alibaba.com>
Message-Id: <1634299161-30101-1-git-send-email-hao.xiang@linux.alibaba.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
WARN if the static keys used to track if any vCPU has disabled its APIC
are left elevated at module exit. Unlike the underflow case, nothing in
the static key infrastructure will complain if a key is left elevated,
and because an elevated key only affects performance, nothing in KVM will
fail if either key is improperly incremented.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211013003554.47705-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Revert a change to open code bits of kvm_lapic_set_base() when emulating
APIC RESET to fix an apic_hw_disabled underflow bug due to arch.apic_base
and apic_hw_disabled being unsyncrhonized when the APIC is created. If
kvm_arch_vcpu_create() fails after creating the APIC, kvm_free_lapic()
will see the initialized-to-zero vcpu->arch.apic_base and decrement
apic_hw_disabled without KVM ever having incremented apic_hw_disabled.
Using kvm_lapic_set_base() in kvm_lapic_reset() is also desirable for a
potential future where KVM supports RESET outside of vCPU creation, in
which case all the side effects of kvm_lapic_set_base() are needed, e.g.
to handle the transition from x2APIC => xAPIC.
Alternatively, KVM could temporarily increment apic_hw_disabled (and call
kvm_lapic_set_base() at RESET), but that's a waste of cycles and would
impact the performance of other vCPUs and VMs. The other subtle side
effect is that updating the xAPIC ID needs to be done at RESET regardless
of whether the APIC was previously enabled, i.e. kvm_lapic_reset() needs
an explicit call to kvm_apic_set_xapic_id() regardless of whether or not
kvm_lapic_set_base() also performs the update. That makes stuffing the
enable bit at vCPU creation slightly more palatable, as doing so affects
only the apic_hw_disabled key.
Opportunistically tweak the comment to explicitly call out the connection
between vcpu->arch.apic_base and apic_hw_disabled, and add a comment to
call out the need to always do kvm_apic_set_xapic_id() at RESET.
Underflow scenario:
kvm_vm_ioctl() {
kvm_vm_ioctl_create_vcpu() {
kvm_arch_vcpu_create() {
if (something_went_wrong)
goto fail_free_lapic;
/* vcpu->arch.apic_base is initialized when something_went_wrong is false. */
kvm_vcpu_reset() {
kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event) {
vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE | MSR_IA32_APICBASE_ENABLE;
}
}
return 0;
fail_free_lapic:
kvm_free_lapic() {
/* vcpu->arch.apic_base is not yet initialized when something_went_wrong is true. */
if (!(vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE))
static_branch_slow_dec_deferred(&apic_hw_disabled); // <= underflow bug.
}
return r;
}
}
}
This (mostly) reverts commit 421221234a.
Fixes: 421221234a ("KVM: x86: Open code necessary bits of kvm_lapic_set_base() at vCPU RESET")
Reported-by: syzbot+9fc046ab2b0cf295a063@syzkaller.appspotmail.com
Debugged-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211013003554.47705-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The refactoring in commit bb18a67774 ("KVM: SEV: Acquire
vcpu mutex when updating VMSA") left behind the assignment to
svm->vcpu.arch.guest_state_protected; add it back.
Signed-off-by: Peter Gonda <pgonda@google.com>
[Delta between v2 and v3 of Peter's patch, which had already been
committed; the commit message is my own. - Paolo]
Fixes: bb18a67774 ("KVM: SEV: Acquire vcpu mutex when updating VMSA")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If allocation of rmaps fails, but some of the pointers have already been written,
those pointers can be cleaned up when the memslot is freed, or even reused later
for another attempt at allocating the rmaps. Therefore there is no need to
WARN, as done for example in memslot_rmap_alloc, but the allocation *must* be
skipped lest KVM will overwrite the previous pointer and will indeed leak memory.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Both arch/nios2/ and drivers/mmc/host/tmio_mmc.c define a macro
with the name "CTL_STATUS". Change the one in arch/nios2/ to be
"CTL_FSTATUS" (flags status) to eliminate the build warning.
In file included from ../drivers/mmc/host/tmio_mmc.c:22:
drivers/mmc/host/tmio_mmc.h:31: warning: "CTL_STATUS" redefined
31 | #define CTL_STATUS 0x1c
arch/nios2/include/asm/registers.h:14: note: this is the location of the previous definition
14 | #define CTL_STATUS 0
Fixes: b31ebd8055 ("nios2: Nios2 registers")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Mapping something twice should be possible as long as,
DMA_ATTR_SKIP_CPU_SYNC is passed to the strictly speaking second relevant
mapping operation (that attempts to map the same thing). So, don't issue a
warning if the specified condition is met in add_dma_entry().
Signed-off-by: Hamza Mahfooz <someguy@effective-light.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull libata fixes from Damien Le Moal:
"Two fixes for this cycle:
- Fix a null pointer dereference in ahci-platform driver (from Hai)
- Fix uninitialized variables in pata_legacy driver (from Dan)"
* tag 'libata-5.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata:
ata: ahci_platform: fix null-ptr-deref in ahci_platform_enable_regulators()
pata_legacy: fix a couple uninitialized variable bugs
Pull block fixes from Jens Axboe:
"Bigger than usual for this point in time, the majority is fixing some
issues around BDI lifetimes with the move from the request_queue to
the disk in this release. In detail:
- Series on draining fs IO for del_gendisk() (Christoph)
- NVMe pull request via Christoph:
- fix the abort command id (Keith Busch)
- nvme: fix per-namespace chardev deletion (Adam Manzanares)
- brd locking scope fix (Tetsuo)
- BFQ fix (Paolo)"
* tag 'block-5.15-2021-10-17' of git://git.kernel.dk/linux-block:
block, bfq: reset last_bfqq_created on group change
block: warn when putting the final reference on a registered disk
brd: reduce the brd_devices_mutex scope
kyber: avoid q->disk dereferences in trace points
block: keep q_usage_counter in atomic mode after del_gendisk
block: drain file system I/O on del_gendisk
block: split bio_queue_enter from blk_queue_enter
block: factor out a blk_try_enter_queue helper
block: call submit_bio_checks under q_usage_counter
nvme: fix per-namespace chardev deletion
block/rnbd-clt-sysfs: fix a couple uninitialized variable bugs
nvme-pci: Fix abort command id
Pull io_uring fix from Jens Axboe:
"Just a single fix for a wrong condition for grabbing a lock, a
regression in this merge window"
* tag 'io_uring-5.15-2021-10-17' of git://git.kernel.dk/linux-block:
io_uring: fix wrong condition to grab uring lock
Pull virtio fixes from Michael Tsirkin:
"Fixes up some issues in rc5"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost-vdpa: Fix the wrong input in config_cb
VDUSE: fix documentation underline warning
Revert "virtio-blk: Add validation for block size in config space"
vhost_vdpa: unset vq irq before freeing irq
virtio: write back F_VERSION_1 before validate
Pull powerpc fixes from Michael Ellerman:
- Fix a bug where guests on P9 with interrupts passed through could get
stuck in synchronize_irq().
- Fix a bug in KVM on P8 where secondary threads entering a guest would
write outside their allocated stack.
- Fix a bug in KVM on P8 where secondary threads could confuse the host
offline code and cause the guest or host to crash.
Thanks to Cédric Le Goater.
* tag 'powerpc-5.15-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
KVM: PPC: Book3S HV: Make idle_kvm_start_guest() return 0 if it went to guest
KVM: PPC: Book3S HV: Fix stack handling in idle_kvm_start_guest()
powerpc/xive: Discard disabled interrupts in get_irqchip_state()
Pull objtool fixes from Borislav Petkov:
- Update section headers before the respective relocations to not
trigger a safety check in elftoolchain's implementation of libelf
- Do not add garbage data to the .rela.orc_unwind_ip section
* tag 'objtool_urgent_for_v5.15_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Update section header before relocations
objtool: Check for gelf_update_rel[a] failures
Pull EDAC fix from Borislav Petkov:
- Log the "correct" uncorrectable error count in the armada_xp driver
* tag 'edac_urgent_for_v5.15_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/armada-xp: Fix output of uncorrectable error counter
Pull perf fix from Borislav Petkov:
- Add Sapphire Rapids to the list of CPUs supporting the SMI count MSR
* tag 'perf_urgent_for_v5.15_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/msr: Add Sapphire Rapids CPU support
