Prior to commit defe21f49b ("KVM: arm64: Move PC rollback on SError to
HYP"), when an SError is synchronised due to another exception, KVM
handles the SError first. If the guest survives, the instruction that
triggered the original exception is re-exectued to handle the first
exception. HVC is treated as a special case as the instruction wouldn't
normally be re-exectued, as its not a trap.
Commit defe21f49b didn't preserve the behaviour of the 'return 1'
that skips the rest of handle_exit().
Since commit defe21f49b, KVM will try to handle the SError and the
original exception at the same time. When the exception was an HVC,
fixup_guest_exit() has already rolled back ELR_EL2, meaning if the
guest has virtual SError masked, it will execute and handle the HVC
twice.
Restore the original behaviour.
Bug: 254441685
Fixes: defe21f49b ("KVM: arm64: Move PC rollback on SError to HYP")
Cc: stable@vger.kernel.org
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127122052.1584324-4-james.morse@arm.com
(cherry picked from commit 1229630af8)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: I04ff663f94b2eb68bb36fbc1e962bd1b9e0f0bfb
When any exception other than an IRQ occurs, the CPU updates the ESR_EL2
register with the exception syndrome. An SError may also become pending,
and will be synchronised by KVM. KVM notes the exception type, and whether
an SError was synchronised in exit_code.
When an exception other than an IRQ occurs, fixup_guest_exit() updates
vcpu->arch.fault.esr_el2 from the hardware register. When an SError was
synchronised, the vcpu esr value is used to determine if the exception
was due to an HVC. If so, ELR_EL2 is moved back one instruction. This
is so that KVM can process the SError first, and re-execute the HVC if
the guest survives the SError.
But if an IRQ synchronises an SError, the vcpu's esr value is stale.
If the previous non-IRQ exception was an HVC, KVM will corrupt ELR_EL2,
causing an unrelated guest instruction to be executed twice.
Check ARM_EXCEPTION_CODE() before messing with ELR_EL2, IRQs don't
update this register so don't need to check.
Bug: 254441685
Fixes: defe21f49b ("KVM: arm64: Move PC rollback on SError to HYP")
Cc: stable@vger.kernel.org
Reported-by: Steven Price <steven.price@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127122052.1584324-3-james.morse@arm.com
(cherry picked from commit 1c71dbc8a1)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: Icd1c7922988bc79d0c04f1b78f41ac89357ec79a
With some chargers, vbus might momentarily raise above VSAFE5V and fall
back to 0V causing VSAFE0V to be triggered. This will
will report a VBUS off event causing TCPM to transition to
SNK_UNATTACHED state where it should be waiting in either SNK_ATTACH_WAIT
or SNK_DEBOUNCED state. This patch makes TCPM avoid VSAFE0V events
while in SNK_ATTACH_WAIT or SNK_DEBOUNCED state.
Stub from the spec:
"4.5.2.2.4.2 Exiting from AttachWait.SNK State
A Sink shall transition to Unattached.SNK when the state of both
the CC1 and CC2 pins is SNK.Open for at least tPDDebounce.
A DRP shall transition to Unattached.SRC when the state of both
the CC1 and CC2 pins is SNK.Open for at least tPDDebounce."
[23.194131] CC1: 0 -> 0, CC2: 0 -> 5 [state SNK_UNATTACHED, polarity 0, connected]
[23.201777] state change SNK_UNATTACHED -> SNK_ATTACH_WAIT [rev3 NONE_AMS]
[23.209949] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS]
[23.300579] VBUS off
[23.300668] state change SNK_ATTACH_WAIT -> SNK_UNATTACHED [rev3 NONE_AMS]
[23.301014] VBUS VSAFE0V
[23.301111] Start toggling
Bug: 254441685
Fixes: 28b43d3d74 ("usb: typec: tcpm: Introduce vsafe0v for vbus")
Cc: stable@vger.kernel.org
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
Link: https://lore.kernel.org/r/20220122015520.332507-2-badhri@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 746f96e7d6)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: Idb8a2ff631e9fdca87aca6b923e5a67923fcd3c3
With the AMS and Collision Avoidance, tcpm often needs to change the CC's
termination. When one CC line is sourcing Vconn, if we still change its
termination, the voltage of the another CC line is likely to be fluctuant
and unstable.
Therefore, we should verify whether a CC line is sourcing Vconn before
changing its termination and only change the termination that is not
a Vconn line. This can be done by reading the Vconn Present bit of
POWER_ STATUS register. To determine the polarity, we can read the
Plug Orientation bit of TCPC_CONTROL register. Since Vconn can only be
sourced if Plug Orientation is set.
Bug: 254441685
Fixes: 0908c5aca3 ("usb: typec: tcpm: AMS and Collision Avoidance")
cc: <stable@vger.kernel.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Link: https://lore.kernel.org/r/20220113092943.752372-1-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 5638b0dfb6)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: I99269bf66fea9735b1227386f8beafce4187b9f4
Mute the warning from "make dtbs_check":
larb@14017000: clock-names: ['apb', 'smi'] is too short
arch/arm64/boot/dts/mediatek/mt8183-evb.dt.yaml
arch/arm64/boot/dts/mediatek/mt8183-kukui-jacuzzi-burnet.dt.yaml
...
larb@16010000: clock-names: ['apb', 'smi'] is too short
arch/arm64/boot/dts/mediatek/mt8183-evb.dt.yaml
arch/arm64/boot/dts/mediatek/mt8183-kukui-jacuzzi-burnet.dt.yaml
larb@17010000: clock-names: ['apb', 'smi'] is too short
arch/arm64/boot/dts/mediatek/mt8183-evb.dt.yaml
arch/arm64/boot/dts/mediatek/mt8183-kukui-jacuzzi-burnet.dt.yaml
If a platform's larb supports gals, there will be some larbs have one
more "gals" clock while the others still only need "apb"/"smi" clocks,
then the minItems for clocks and clock-names are 2.
Bug: 254441685
Fixes: 27bb0e4285 ("dt-bindings: memory: mediatek: Convert SMI to DT schema")
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220113111057.29918-4-yong.wu@mediatek.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
(cherry picked from commit 996ebc0e33)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: I04c75dbb321cabb23176afff57ae46df235141f9
Mute the warning from "make dtbs_check":
larb@14016000: 'mediatek,larb-id' is a required property
arch/arm64/boot/dts/mediatek/mt8167-pumpkin.dt.yaml
larb@15001000: 'mediatek,larb-id' is a required property
arch/arm64/boot/dts/mediatek/mt8167-pumpkin.dt.yaml
larb@16010000: 'mediatek,larb-id' is a required property
arch/arm64/boot/dts/mediatek/mt8167-pumpkin.dt.yaml
As the description of mediatek,larb-id, the property is only
required when the larbid is not consecutive from its IOMMU point of view.
Also, from the description of mediatek,larbs in
Documentation/devicetree/bindings/iommu/mediatek,iommu.yaml, all the larbs
must sort by the larb index.
In mt8167, there is only one IOMMU HW and three larbs. The drivers already
know its larb index from the mediatek,larbs property of IOMMU, thus no
need this property.
Bug: 254441685
Fixes: 27bb0e4285 ("dt-bindings: memory: mediatek: Convert SMI to DT schema")
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Acked-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220113111057.29918-3-yong.wu@mediatek.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
(cherry picked from commit ddc3a32488)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: I31ba0772a094d73c3368505e291abb9b36f3129b
Since commit 57fd251c78 ("kbuild: split cc-option and friends to
scripts/Makefile.compiler"), some kselftests fail to build.
The tools/ directory opted out Kbuild, and went in a different
direction. People copied scripts and Makefiles to the tools/ directory
to create their own build system.
tools/build/Build.include mimics scripts/Kbuild.include, but some
tool Makefiles include the Kbuild one to import a feature that is
missing in tools/build/Build.include:
- Commit ec04aa3ae8 ("tools/thermal: tmon: use "-fstack-protector"
only if supported") included scripts/Kbuild.include from
tools/thermal/tmon/Makefile to import the cc-option macro.
- Commit c2390f16fc ("selftests: kvm: fix for compilers that do
not support -no-pie") included scripts/Kbuild.include from
tools/testing/selftests/kvm/Makefile to import the try-run macro.
- Commit 9cae4ace80 ("selftests/bpf: do not ignore clang
failures") included scripts/Kbuild.include from
tools/testing/selftests/bpf/Makefile to import the .DELETE_ON_ERROR
target.
- Commit 0695f8bca9 ("selftests/powerpc: Handle Makefile for
unrecognized option") included scripts/Kbuild.include from
tools/testing/selftests/powerpc/pmu/ebb/Makefile to import the
try-run macro.
Copy what they need into tools/build/Build.include, and make them
include it instead of scripts/Kbuild.include.
Bug: 254441685
Link: https://lore.kernel.org/lkml/86dadf33-70f7-a5ac-cb8c-64966d2f45a1@linux.ibm.com/
Fixes: 57fd251c78 ("kbuild: split cc-option and friends to scripts/Makefile.compiler")
Reported-by: Janosch Frank <frankja@linux.ibm.com>
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Yonghong Song <yhs@fb.com>
(cherry picked from commit b61442df74)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: Ie17d3ba0bb20a7457a31d10a7c09163aa10e0ea4
Commit aec6c60a01 ("kbuild: check the minimum compiler version in
Kconfig") changed how the script detects the compiler version.
Get 'make CROSS_COMPILE=scripts/dummy-tools/' back working again.
Bug: 254441685
Fixes: aec6c60a01 ("kbuild: check the minimum compiler version in Kconfig")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
(cherry picked from commit f9bc754be4)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: I0ce942de1dbc16dd8b974296bc2fd3cc703e49e5
Commit cd195bc477 ("kbuild: split adjust_autoksyms.sh in two parts")
split out the code that needs include/config/auto.conf.
This script no longer needs to include include/config/auto.conf.
Bug: 254441685
Fixes: cd195bc477 ("kbuild: split adjust_autoksyms.sh in two parts")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
(cherry picked from commit 12e9dea6c9)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: I1c2cb44a3266e935f1c23cf8c4edd90ca1a05a0f
Enable the UVC function driver to allow USB gadgets
to connect as a standard video device to a host.
Bug: 200712777
Bug: 242344221
Signed-off-by: Dan Vacura <w36195@motorola.com>
Change-Id: Ia037f8560664f9e98f28f3fede609764d5d5699d
(cherry picked from commit 8d5dd0a5a4)
(cherry picked from commit 885f16fab68e456b9dc9856641b706ce17551456)
NUMA support with speculative page faults might be broken if
vma_replace_policy() replaces the mempolicy object used in
do_anonymous_page()
alloc_zeroed_user_highpage_movable()
alloc_page_vma()
alloc_pages_vma()
get_vma_policy()
__get_vma_policy() in speculative path does not always refcounts the
mempolicy object, therefore can't be relied on stabilizing it.
Rather than fixing this, just disable speculation for CONFIG_NUMA
for now and fix it if it's ever needed in Android.
Bug: 257443051
Change-Id: Ib5750b9809979a69a42ebfa6c130e123f416f1aa
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Invalid condition was introduced when porting the original SPF patch
which would affect NUMA mode.
Fixes: 736ae8bde8 ("FROMLIST: mm: adding speculative page fault failure trace events")
Bug: 257443051
Change-Id: Ib20c625615b279dc467588933a1f598dc179861b
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
move_page_tables() can move entire pmd or pud without locking individual
ptes. This is problematic for speculative page faults which do not take
mmap_lock because they rely on ptl lock when writing new pte value. To
avoid possible race, disable move_page_tables() optimization when
CONFIG_SPECULATIVE_PAGE_FAULT is enabled.
Bug: 257443051
Change-Id: Ib48dda08ecad1abc60d08fc089a6566a63393c13
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
vm_write_{begin|end} has to be called when mmap_lock is taken
exlusively. Add an assert statement in vm_write_begin to enforce
that. free_pgtables can free page tables without exclusive mmap_lock
if the vma was isolated, therefore avoid assertions in such cases.
Bug: 257443051
Change-Id: Ie81aefe025c743cda6f66717d2f08f4d78a55608
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
In a number of cases vm_write_{begin|end} is called while mmap_lock is
not owned exclusively. This is unnecessary and can affect correctness of
the sequence counting protecting speculative page fault handlers. Remove
extra calls.
Bug: 257443051
Change-Id: I1278638a0794448e22fbdab5601212b3b2eaebdc
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Speculative page fault handler needs to detect concurrent pmd changes
and relies on vma seqcount for that. pmdp_collapse_flush(), set_huge_pmd() and collapse_and_free_pmd() can modify a pmd.
vm_write_{begin|end} are needed in the paths which can call these
functions for page fault handler to detect pmd changes.
Bug: 257443051
Change-Id: Ieb784b5f44901b66a594f61b9e7c91190ff97f80
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Extend filemap_fault() to handle speculative faults.
In the speculative case, we will only be fishing existing pages out of
the page cache. The logic we use mirrors what is done in the
non-speculative case, assuming that pages are found in the page cache,
are up to date and not already locked, and that readahead is not
necessary at this time. In all other cases, the fault is aborted to be
handled non-speculatively.
Signed-off-by: Michel Lespinasse <michel@lespinasse.org>
Link: https://lore.kernel.org/all/20210407014502.24091-26-michel@lespinasse.org/
Conflicts:
mm/filemap.c
1. Added back file_ra_state variable used by SPF path.
2. Updated comment for filemap_fault to reflect SPF locking rules.
Bug: 161210518
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: I82eba7fcfc81876245c2e65bc5ae3d33ddfcc368
Checks of pmd during speculative page fault handling are racy because
pmd is unprotected and might be modified or cleared. This might cause
use-after-free reads from speculative path, therefore prevent such
checks. At the beginning of speculation pmd is checked to be valid and
if it's changed before page fault is handled, the change will be detected
and page fault will be retried under mmap_lock protection.
Bug: 257443051
Change-Id: I0cbd3b0b44e8296cf0d6cb298fae48c696580068
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
handle_userfault() should be protected against a concurrent
userfaultfd_release(), therefore handling a userfaults speculatively
without mmap_lock protection should be disallowed.
Bug: 257443051
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: Ic6ae39329c73e8849048ea15b5351a49346404d3
Speculative page fault checks pmd to be valid before starting to handle
the page fault and pte_alloc() should do nothing if pmd stays valid.
If pmd gets changed during speculative page fault, we will detect the
change later and retry with mmap_lock. Therefore pte_alloc() can be
safely skipped and this prevents the racy pmd_lock() call which can
access pmd->ptl after pmd was cleared.
Bug: 257443051
Change-Id: Iec57df5530dba6e0e0bdf9f7500f910851c3d3fd
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
When a task yields, it relinquishes the cpu and
scheduler is tasked to find another task.
However our vendor scheduler logic implementation
could return the same task leading to a loop where
the yielded task gets to run back, so add hook point
in do_sched_yield() for vendor can do some work
before task is scheduled.
Bug: 205804537
Change-Id: I6528c3f4b0ee360559ef9c97cb1eb2b2d1357870
Signed-off-by: Tengfei Fan <quic_tengfan@quicinc.com>
Signed-off-by: Sai Harshini Nimmala <quic_snimmala@quicinc.com>
Signed-off-by: Khalid Shaik <khalid.s@samsung.com>
SysMMU_SYNCs provide an invalidation-complete signal to the S2MPU
driver but the latency can be quite high. Improve this by waiting for
all the SYNCs in parallel - separate the initiation of invalidation
barrier from waiting for completion. This way we initiate invalidation
on all SYNCs first, then wait for all of them to complete.
The previously introduced exponential-backoff only kicks in if the
SYNC_COMP_COMPLETE bit is not set after the parallel invalidation.
Bug: 249161451
Signed-off-by: David Brazdil <dbrazdil@google.com>
Change-Id: I9d544bc65f8633d376c7ccd65ea23195ca432964
Add a new callback to pkvm_iommu_ops called after
host_stage2_idmap_apply on all IOMMU devices. This allows the drivers to
complete operations like invalidation in two stages.
Bug: 249161451
Signed-off-by: David Brazdil <dbrazdil@google.com>
Change-Id: I9c077fd2b18ce54ad67eb34ef16bc94428797419
On the guest teardown path, pKVM will zero the pages used to back the
guest shadow data structures before returning them to the host as they
may contain secrets (e.g. in the vCPU registers). However, the zeroing
is done using a cacheable alias, and CMOs are missing, hence giving the
host a potential opportunity to read the original content of the shadow
structs from memory.
Fix this by issuing CMOs after zeroing the pages.
Bug: 259551298
Change-Id: Id696d47d16e4c3fd870cb70b792eeb7f2282fc78
Signed-off-by: Quentin Perret <qperret@google.com>
This will allow a client program to avoid redundant actions on ashmem
buffers which it has already seen.
Bug: 244233389
Change-Id: Ica57a8842ff163eae5f9eca8141b439091ec0940
Signed-off-by: Mark Fasheh <mfasheh@google.com>
If the host issues a PSCI SYSTEM_RESET2 call requesting a warm reset
while guest pages are live in the system, then pKVM attempts to convert
this to a cold PSCI SYSTEM_RESET request to ensure the EL3 will clear
memory on the next boot. However, this logic is quite badly broken and
will instead attempt to take the 'mem_protect_lock' spinlock twice which
results in a deadlock.
Fix the repainting so that the 'host_ctxt' is updated inline and we
forward the updated request directly to EL3.
Signed-off-by: Will Deacon <will@kernel.org>
Bug: 259523340
Signed-off-by: Will Deacon <willdeacon@google.com>
Change-Id: I44719466b7f5abddf73730a3b74db13f935f92ec
Export reweight_task for vendor usage when they are trying to manipulate
task prio. After the prio changed, it will need to update its load
weight to take effect. Therefore, this function needs to be called
from vendor kernel module. It could be used with
trace_android_rvh_set_user_nice and trace_android_rvh_setscheduler.
Bug: 245675204
Change-Id: I0033518bf1cbd0a8129795743b95340f439d5fe8
Signed-off-by: Rick Yiu <rickyiu@google.com>
If block address is still alive, we should give a valid node block even after
shutdown. Otherwise, we can see zero data when reading out a file.
Bug: 257271565
Cc: stable@vger.kernel.org
Fixes: 83a3bfdb5a ("f2fs: indicate shutdown f2fs to allow unmount successfully")
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
(cherry picked from commit 6953bf65286d git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs.git dev)
Change-Id: Ifb70f6c73bd67d5112ee9fa1a5e4ad8e10ae8517
When a broken USB accessory connects to a USB host, usbcore might
keep doing enumeration retries. If the host has a watchdog mechanism,
the kernel panic will happen on the host.
This patch provides an attribute early_stop to limit the numbers of retries
for each port of a hub. If a port was marked with early_stop attribute,
unsuccessful connection attempts will fail quickly. In addition, if an
early_stop port has failed to initialize, it will ignore all future
connection events until early_stop attribute is clear.
Signed-off-by: Ray Chi <raychi@google.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20221107072754.3336357-1-raychi@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bug: 236915598
(cherry picked from commit 430d57f53e
https: //git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git/ usb-next)
Change-Id: Ib85522ca38c0f26ece9807d5304991853f155669
Signed-off-by: Ray Chi <raychi@google.com>
When a protected guest shares or unshares a page with the host, we
should decrement and increment the PSCI MEM_PROTECT refcount respectively
since shared pages do not require poisoning on the reclaim path and will
therefore not be accounted for.
Bug: 258425493
Reported-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <willdeacon@google.com>
Change-Id: I80a4fad44de4313c6708a8259a1802ded379f03b
The recent change of page_cache_ra_unbounded() arguments was buggy in the
two callers, causing us to readahead the wrong pages. Move the definition
of ractl down to after the index is set correctly. This affected
performance on configurations that use fs-verity.
Link: https://lkml.kernel.org/r/20221012193419.1453558-1-willy@infradead.org
Fixes: 73bb49da50 ("mm/readahead: make page_cache_ra_unbounded take a readahead_control")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reported-by: Jintao Yin <nicememory@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 258554362
(cherry picked from commit 4fa0e3ff21)
Change-Id: Ib5160c5c53629be328c370f5d5d464956d6a6312
Signed-off-by: Eric Biggers <ebiggers@google.com>
We shouldn't hold lru_lock to proceed blk_finish_plug.
Fixes: 89fed37332 ("ANDROID: vendor hook to control blk_plug for shrink_lruvec")
Bug: 255471591
Change-Id: Ie9d9b0e4ee76b4735e802b2a202fbb79d0ae090e
Signed-off-by: Martin Liu <liumartin@google.com>
When I/O is submitted to dm-user target, bio already
has a referance. Additional referance is not needed
in the I/O path.
Bug: 229696117
Test: OTA on Pixel
Change-Id: I8db6802e751336d7a10c6de0bc7a247a6d7f6b37
Signed-off-by: Akilesh Kailash <akailash@google.com>