iov_iter for ep_read_iter can be ITER_UBUF with io_uring.
In that case dup_iter() does not have to allocate iov and it can
return NULL. Fix the assumption by checking for iter_is_ubuf()
other wise ep_read_iter can treat this as failure and return -ENOMEM.
Fixes: 1e23db450c ("io_uring: use iter_ubuf for single range imports")
Signed-off-by: Sandeep Dhavale <dhavale@google.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/20230401060509.3608259-3-dhavale@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
iov_iter for ffs_epfile_read_iter can be ITER_UBUF with io_uring.
In that case dup_iter() does not have to allocate anything and it
can return NULL. ffs_epfile_read_iter treats this as a failure and
returns -ENOMEM. Fix it by checking if iter_is_ubuf().
Fixes: 1e23db450c ("io_uring: use iter_ubuf for single range imports")
Signed-off-by: Sandeep Dhavale <dhavale@google.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/20230401060509.3608259-2-dhavale@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While determining the initial pin assignment to be sent in the configure
message, using the DP_PIN_ASSIGN_DP_ONLY_MASK mask causes the DFP_U to
send both Pin Assignment C and E when both are supported by the DFP_U and
UFP_U. The spec (Table 5-7 DFP_U Pin Assignment Selection Mandates,
VESA DisplayPort Alt Mode Standard v2.0) indicates that the DFP_U never
selects Pin Assignment E when Pin Assignment C is offered.
Update the DP_PIN_ASSIGN_DP_ONLY_MASK conditional to intially select only
Pin Assignment C if it is available.
Fixes: 0e3bb7d689 ("usb: typec: Add driver for DisplayPort alternate mode")
Cc: stable@vger.kernel.org
Signed-off-by: RD Babiera <rdbabiera@google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230329215159.2046932-1-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Dan reports that smatch complains about a potential uninitialized
variable being used in the compat alignment fixup code.
The logic is not wrong per se, but we do end up using an uninitialized
variable if reading the instruction that triggered the alignment fault
from user space faults, even if the fault ensures that the uninitialized
value doesn't propagate any further.
Given that we just give up and return 1 if any fault occurs when reading
the instruction, let's get rid of the 'success handling' pattern that
captures the fault in a variable and aborts later, and instead, just
return 1 immediately if any of the get_user() calls result in an
exception.
Fixes: 3fc24ef32d ("arm64: compat: Implement misalignment fixups for multiword loads")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/r/202304021214.gekJ8yRc-lkp@intel.com/
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20230404103625.2386382-1-ardb@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Pull tracing fixes from Steven Rostedt:
- Fix timerlat notification, as it was not triggering the notify to
users when a new max latency was hit.
- Do not trigger max latency if the tracing is off.
When tracing is off, the ring buffer is not updated, it does not make
sense to notify when there's a new max latency detected by the
tracer, as why that latency happened is not available. The tracing
logic still runs when the ring buffer is disabled, but it should not
be triggering notifications.
- Fix race on freeing the synthetic event "last_cmd" variable by adding
a mutex around it.
- Fix race between reader and writer of the ring buffer by adding
memory barriers. When the writer is still on the reader page it must
have its content visible on the buffer before it moves the commit
index that the reader uses to know how much content is on the page.
- Make get_lock_parent_ip() always inlined, as it uses _THIS_IP_ and
_RET_IP_, which gets broken if it is not inlined.
- Make __field(int, arr[5]) in a TRACE_EVENT() macro fail to build.
The field formats of trace events are calculated by using
sizeof(type) and other means by what is passed into the structure
macros like __field(). The __field() macro is only meant for atom
types like int, long, short, pointer, etc. It is not meant for
arrays.
The code will currently compile with arrays, but then the format
produced will be inaccurate, and user space parsing tools will break.
Two bugs have already been fixed, now add code that will make the
kernel fail to build if another trace event includes this buggy field
format.
- Fix boot up snapshot code:
Boot snapshots were triggering when not even asked for on the kernel
command line. This was caused by two bugs:
1) It would trigger a snapshot on any instance if one was created
from the kernel command line.
2) The error handling would only affect the top level instance.
So the fact that a snapshot was done on a instance that didn't
allocate a buffer triggered a warning written into the top level
buffer, and worse yet, disabled the top level buffer.
- Fix memory leak that was caused when an error was logged in a trace
buffer instance, and then the buffer instance was removed.
The allocated error log messages still needed to be freed.
* tag 'trace-v6.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Free error logs of tracing instances
tracing: Fix ftrace_boot_snapshot command line logic
tracing: Have tracing_snapshot_instance_cond() write errors to the appropriate instance
tracing: Error if a trace event has an array for a __field()
tracing/osnoise: Fix notify new tracing_max_latency
tracing/timerlat: Notify new max thread latency
ftrace: Mark get_lock_parent_ip() __always_inline
ring-buffer: Fix race while reader and writer are on the same page
tracing/synthetic: Fix races on freeing last_cmd
The device can report discard support without setting the ONCS DSM bit.
When not set, the driver clears max_discard_size expecting it to be set
later. We don't know the size until we have the namespace format,
though, so setting it is deferred until configuring one, but the driver
was abandoning the discard settings due to that initial clearing.
Move the max_discard_size calculation above the check for a '0' discard
size.
Fixes: 1a86924e4f ("nvme: fix interpretation of DMRSL")
Reported-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Tested-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
In the j1939_tp_tx_dat_new() function, an out-of-bounds memory access
could occur during the memcpy() operation if the size of skb->cb is
larger than the size of struct j1939_sk_buff_cb. This is because the
memcpy() operation uses the size of skb->cb, leading to a read beyond
the struct j1939_sk_buff_cb.
Updated the memcpy() operation to use the size of struct
j1939_sk_buff_cb instead of the size of skb->cb. This ensures that the
memcpy() operation only reads the memory within the bounds of struct
j1939_sk_buff_cb, preventing out-of-bounds memory access.
Additionally, add a BUILD_BUG_ON() to check that the size of skb->cb
is greater than or equal to the size of struct j1939_sk_buff_cb. This
ensures that the skb->cb buffer is large enough to hold the
j1939_sk_buff_cb structure.
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Reported-by: Shuangpeng Bai <sjb7183@psu.edu>
Tested-by: Shuangpeng Bai <sjb7183@psu.edu>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://groups.google.com/g/syzkaller/c/G_LL-C3plRs/m/-8xCi6dCAgAJ
Link: https://lore.kernel.org/all/20230404073128.3173900-1-o.rempel@pengutronix.de
Cc: stable@vger.kernel.org
[mkl: rephrase commit message]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The same task check in perf_event_set_output has some potential issues
for some usages.
For the current perf code, there is a problem if using of
perf_event_open() to have multiple samples getting into the same mmap’d
memory when they are both attached to the same process.
https://lore.kernel.org/all/92645262-D319-4068-9C44-2409EF44888E@gmail.com/
Because the event->ctx is not ready when the perf_event_set_output() is
invoked in the perf_event_open().
Besides the above issue, before the commit bd27568117 ("perf: Rewrite
core context handling"), perf record can errors out when sampling with
a hardware event and a software event as below.
$ perf record -e cycles,dummy --per-thread ls
failed to mmap with 22 (Invalid argument)
That's because that prior to the commit a hardware event and a software
event are from different task context.
The problem should be a long time issue since commit c3f00c7027
("perk: Separate find_get_context() from event initialization").
The task struct is stored in the event->hw.target for each per-thread
event. It is a more reliable way to determine whether two events are
attached to the same task.
The event->hw.target was also introduced several years ago by the
commit 50f16a8bf9 ("perf: Remove type specific target pointers"). It
can not only be used to fix the issue with the current code, but also
back port to fix the issues with an older kernel.
Note: The event->hw.target was introduced later than commit
c3f00c7027. The patch may cannot be applied between the commit
c3f00c7027 and commit 50f16a8bf9. Anybody that wants to back-port
this at that period may have to find other solutions.
Fixes: c3f00c7027 ("perf: Separate find_get_context() from event initialization")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Link: https://lkml.kernel.org/r/20230322202449.512091-1-kan.liang@linux.intel.com
Currently job->done_fence is added to every BO handle within a job. If job
handle (command buffer) is shared between multiple submits, KMD will add
the fence in each of them. Then bo_wait_ioctl() executed on command buffer
will exit only when all jobs containing that handle are done.
This creates deadlock scenario for user mode driver in case when job handle
is added as dependency of another job, because bo_wait_ioctl() of first job
will wait until second job finishes, and second job can not finish before
first one.
Having fences added only to job buffer handle allows user space to execute
bo_wait_ioctl() on the job even if it's handle is submitted with other job.
Fixes: cd7272215c ("accel/ivpu: Add command buffer submission logic")
Signed-off-by: Karol Wachowski <karol.wachowski@linux.intel.com>
Signed-off-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230331113603.2802515-2-stanislaw.gruszka@linux.intel.com
The kernel command line ftrace_boot_snapshot by itself is supposed to
trigger a snapshot at the end of boot up of the main top level trace
buffer. A ftrace_boot_snapshot=foo will do the same for an instance called
foo that was created by trace_instance=foo,...
The logic was broken where if ftrace_boot_snapshot was by itself, it would
trigger a snapshot for all instances that had tracing enabled, regardless
if it asked for a snapshot or not.
When a snapshot is requested for a buffer, the buffer's
tr->allocated_snapshot is set to true. Use that to know if a trace buffer
wants a snapshot at boot up or not.
Since the top level buffer is part of the ftrace_trace_arrays list,
there's no reason to treat it differently than the other buffers. Just
iterate the list if ftrace_boot_snapshot was specified.
Link: https://lkml.kernel.org/r/20230405022341.895334039@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ross Zwisler <zwisler@google.com>
Fixes: 9c1c251d67 ("tracing: Allow boot instances to have snapshot buffers")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The arguments passed to the trace events are of type unsigned int,
however the signature of the events used __le32 parameters.
I may be missing the point here, but sparse flagged this and it
does seem incorrect to me.
net/qrtr/ns.c: note: in included file (through include/trace/trace_events.h, include/trace/define_trace.h, include/trace/events/qrtr.h):
./include/trace/events/qrtr.h:11:1: warning: cast to restricted __le32
./include/trace/events/qrtr.h:11:1: warning: restricted __le32 degrades to integer
./include/trace/events/qrtr.h:11:1: warning: restricted __le32 degrades to integer
... (a lot more similar warnings)
net/qrtr/ns.c:115:47: expected restricted __le32 [usertype] service
net/qrtr/ns.c:115:47: got unsigned int service
net/qrtr/ns.c:115:61: warning: incorrect type in argument 2 (different base types)
... (a lot more similar warnings)
Fixes: dfddb54043 ("net: qrtr: Add tracepoint support")
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230402-qrtr-trace-types-v1-1-92ad55008dd3@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Non-GSO TCP packets whose SKBs' linear portion did not include the
entire TCP header were not populating the first Tx descriptor with
as many bytes as the vNIC expected. This change ensures that all
TCP packets populate the first descriptor with the correct number of
bytes.
Fixes: 893ce44df5 ("gve: Add basic driver framework for Compute Engine Virtual NIC")
Signed-off-by: Shailend Chand <shailend@google.com>
Link: https://lore.kernel.org/r/20230403172809.2939306-1-shailend@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If the number of lanes was forced and then subsequently the user
omits this parameter, the ksettings->lanes is reset. The driver
should then reset the number of lanes to the device's default
for the specified speed.
However, although the ksettings->lanes is set to 0, the mod variable
is not set to true to indicate the driver and userspace should be
notified of the changes.
The consequence is that the same ethtool operation will produce
different results based on the initial state.
If the initial state is:
$ ethtool swp1 | grep -A 3 'Speed: '
Speed: 500000Mb/s
Lanes: 2
Duplex: Full
Auto-negotiation: on
then executing 'ethtool -s swp1 speed 50000 autoneg off' will yield:
$ ethtool swp1 | grep -A 3 'Speed: '
Speed: 500000Mb/s
Lanes: 2
Duplex: Full
Auto-negotiation: off
While if the initial state is:
$ ethtool swp1 | grep -A 3 'Speed: '
Speed: 500000Mb/s
Lanes: 1
Duplex: Full
Auto-negotiation: off
executing the same 'ethtool -s swp1 speed 50000 autoneg off' results in:
$ ethtool swp1 | grep -A 3 'Speed: '
Speed: 500000Mb/s
Lanes: 1
Duplex: Full
Auto-negotiation: off
This patch fixes this behavior. Omitting lanes will always results in
the driver choosing the default lane width for the chosen speed. In this
scenario, regardless of the initial state, the end state will be, e.g.,
$ ethtool swp1 | grep -A 3 'Speed: '
Speed: 500000Mb/s
Lanes: 2
Duplex: Full
Auto-negotiation: off
Fixes: 012ce4dd31 ("ethtool: Extend link modes settings uAPI with lanes")
Signed-off-by: Andy Roulin <aroulin@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/ac238d6b-8726-8156-3810-6471291dbc7f@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Kuniyuki Iwashima says:
====================
raw/ping: Fix locking in /proc/net/{raw,icmp}.
The first patch fixes a NULL deref for /proc/net/raw and second one fixes
the same issue for ping sockets.
The first patch also converts hlist_nulls to hlist, but this is because
the current code uses sk_nulls_for_each() for lockless readers, instead
of sk_nulls_for_each_rcu() which adds memory barrier, but raw sockets
does not use the nulls marker nor SLAB_TYPESAFE_BY_RCU in the first place.
OTOH, the ping sockets already uses sk_nulls_for_each_rcu(), and such
conversion can be posted later for net-next.
====================
Link: https://lore.kernel.org/r/20230403194959.48928-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
After commit dbca1596bb ("ping: convert to RCU lookups, get rid
of rwlock"), we use RCU for ping sockets, but we should use spinlock
for /proc/net/icmp to avoid a potential NULL deref mentioned in
the previous patch.
Let's go back to using spinlock there.
Note we can convert ping sockets to use hlist instead of hlist_nulls
because we do not use SLAB_TYPESAFE_BY_RCU for ping sockets.
Fixes: dbca1596bb ("ping: convert to RCU lookups, get rid of rwlock")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Alexei Starovoitov says:
====================
From: Alexei Starovoitov <ast@kernel.org>
The patch set is addressing a fallout from
commit 6fcd486b3a ("bpf: Refactor RCU enforcement in the verifier.")
It was too aggressive with PTR_UNTRUSTED marks.
Patches 1-6 are cleanup and adding verifier smartness to address real
use cases in bpf programs that broke with too aggressive PTR_UNTRUSTED.
The partial revert is done in patch 7 anyway.
====================
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
The commit 6fcd486b3a ("bpf: Refactor RCU enforcement in the verifier.")
broke several tracing bpf programs. Even in clang compiled kernels there are
many fields that are not marked with __rcu that are safe to read and pass into
helpers, but the verifier doesn't know that they're safe. Aggressively marking
them as PTR_UNTRUSTED was premature.
Fixes: 6fcd486b3a ("bpf: Refactor RCU enforcement in the verifier.")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230404045029.82870-8-alexei.starovoitov@gmail.com
check_reg_type() unconditionally disallows PTR_TO_BTF_ID | PTR_MAYBE_NULL.
It's problematic for helpers that allow ARG_PTR_TO_BTF_ID_OR_NULL like
bpf_sk_storage_get(). Allow passing PTR_TO_BTF_ID | PTR_MAYBE_NULL into such
helpers. That technically includes bpf_kptr_xchg() helper, but in practice:
bpf_kptr_xchg(..., bpf_cpumask_create());
is still disallowed because bpf_cpumask_create() returns ref counted pointer
with ref_obj_id > 0.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230404045029.82870-6-alexei.starovoitov@gmail.com
bpf_[sk|inode|task|cgrp]_storage_[get|delete]() and bpf_get_socket_cookie() helpers
perform run-time check that sk|inode|task|cgrp pointer != NULL.
Teach verifier about this fact and allow bpf programs to pass
PTR_TO_BTF_ID | PTR_MAYBE_NULL into such helpers.
It will be used in the subsequent patch that will do
bpf_sk_storage_get(.., skb->sk, ...);
Even when 'skb' pointer is trusted the 'sk' pointer may be NULL.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230404045029.82870-5-alexei.starovoitov@gmail.com
btf_nested_type_is_trusted() tries to find a struct member at corresponding offset.
It works for flat structures and falls apart in more complex structs with nested structs.
The offset->member search is already performed by btf_struct_walk() including nested structs.
Reuse this work and pass {field name, field btf id} into btf_nested_type_is_trusted()
instead of offset to make BTF_TYPE_SAFE*() logic more robust.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230404045029.82870-4-alexei.starovoitov@gmail.com
Remove duplicated if (atype == BPF_READ) btf_struct_access() from
btf_struct_access() callback and invoke it only for writes. This is
possible to do because currently btf_struct_access() custom callback
always delegates to generic btf_struct_access() helper for BPF_READ
accesses.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230404045029.82870-2-alexei.starovoitov@gmail.com
bpf_testmod.ko sometimes fails to build from a clean checkout:
BTF [M] linux/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.ko
/bin/sh: 1: linux-build//tools/build/resolve_btfids/resolve_btfids: not found
The reason is that RESOLVE_BTFIDS may not yet be built. Fix by adding a
dependency.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230403172935.1553022-1-iii@linux.ibm.com
One motivation for mapping range registers to decoder objects is
to use those settings for region autodiscovery.
The need to map a region for devices programmed to use range registers
is especially urgent now that the kernel no longer routes "Soft
Reserved" ranges in the memory map to device-dax by default. The CXL
memory range loses all access mechanisms.
Complete the implementation by marking the DPA reservation and setting
the endpoint-decoder state to signal autodiscovery. Note that the
default settings of ways=1 and granularity=4096 set in cxl_decode_init()
do not need to be updated.
Fixes: 09d09e04d2 ("cxl/dax: Create dax devices for CXL RAM regions")
Tested-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Gregory Price <gregory.price@memverge.com>
Link: https://lore.kernel.org/r/168012575521.221280.14177293493678527326.stgit@dwillia2-xfh.jf.intel.com
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Recall that range register emulation seeks to treat the 2 potential
range registers as Linux CXL "decoder" objects. The number of range
registers can be 1 or 2, while HDM decoder ranges can include more than
2.
Be careful not to confuse DVSEC range count with HDM capability decoder
count. Commit to range register earlier in devm_cxl_setup_hdm().
Otherwise, a device with more HDM decoders than range registers can set
@cxlhdm->decoder_count to an invalid value.
Avoid introducing a forward declaration by just moving the definition of
should_emulate_decoders() earlier in the file. should_emulate_decoders()
is unchanged.
Tested-by: Dave Jiang <dave.jiang@intel.com>
Fixes: d7a2153762 ("cxl/hdm: Add emulation when HDM decoders are not committed")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168012574932.221280.15944705098679646436.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Each time the contents of a given HPA are potentially changed in a cache
incoherent manner the CXL core sets CXL_REGION_F_INCOHERENT to
invalidate CPU caches before the region is used.
Successful invocation of attach_target() indicates that DPA has been
newly assigned to a given HPA in the dynamic region creation flow.
However, attach_target() is also reused in the autodiscovery flow where
the region was activated by platform firmware. In that case there is no
need to invalidate caches because that region is already in active use
and nothing about the autodiscovery flow modifies the HPA-to-DPA
relationship.
In the autodiscovery case cxl_region_attach() exits early after
determining the endpoint decoder is already correctly attached to the
region.
Fixes: a32320b71f ("cxl/region: Add region autodiscovery")
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168002858817.50647.1217607907088920888.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
RCDs (CXL memory devices that link train without VH capability and show
up as root complex integrated endpoints), hide the presence of the link
between the endpoint and the host-bridge. The CXL region setup/teardown
paths assume that a link hop is present and go looking for at least one
'struct cxl_port' instance between the CXL root port-object and an
endpoint port-object leading to crashes of the form:
BUG: kernel NULL pointer dereference, address: 0000000000000008
[..]
RIP: 0010:cxl_region_setup_targets+0x3e9/0xae0 [cxl_core]
[..]
Call Trace:
<TASK>
cxl_region_attach+0x46c/0x7a0 [cxl_core]
cxl_create_region+0x20b/0x270 [cxl_core]
cxl_mock_mem_probe+0x641/0x800 [cxl_mock_mem]
platform_probe+0x5b/0xb0
Detect RCDs explicitly and skip walking the non-existent port hierarchy
between root and endpoint in that case.
While this has been a problem since:
commit 0a19bfc8de ("cxl/port: Add RCD endpoint port enumeration")
...it becomes a more reliable crash scenario with the new autodiscovery
implementation.
Fixes: a32320b71f ("cxl/region: Add region autodiscovery")
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168002858268.50647.728091521032131326.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The find_cxl_root() helper is used to lookup root decoders and other CXL
platform topology information for a given endpoint. It turns out that
for RCDs it has never worked. The result of find_cxl_root(&cxlmd->dev)
is always NULL for the RCH topology case because it expects to find a
cxl_port at the host-bridge. RCH topologies only have the root cxl_port
object with the host-bridge as a dport. While there are no reports of
this being a problem to date, by inspection region enumeration should
crash as a result of this problem, and it does in a local unit test for
this scenario.
However, an observation that ever since:
commit f17b558d66 ("cxl/pmem: Refactor nvdimm device registration, delete the workqueue")
...all callers of find_cxl_root() occur after the memdev connection to
the port topology has been established. That means that find_cxl_root()
can be simplified to a walk of the endpoint port topology to the root.
Switch to that arrangement which also fixes the RCD bug.
Fixes: a32320b71f ("cxl/region: Add region autodiscovery")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168002857715.50647.344876437247313909.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull kvm fixes from Paolo Bonzini:
"PPC:
- Hide KVM_CAP_IRQFD_RESAMPLE if XIVE is enabled
s390:
- Fix handling of external interrupts in protected guests
x86:
- Resample the pending state of IOAPIC interrupts when unmasking them
- Fix usage of Hyper-V "enlightened TLB" on AMD
- Small fixes to real mode exceptions
- Suppress pending MMIO write exits if emulator detects exception
Documentation:
- Fix rST syntax"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
docs: kvm: x86: Fix broken field list
KVM: PPC: Make KVM_CAP_IRQFD_RESAMPLE platform dependent
KVM: s390: pv: fix external interruption loop not always detected
KVM: nVMX: Do not report error code when synthesizing VM-Exit from Real Mode
KVM: x86: Clear "has_error_code", not "error_code", for RM exception injection
KVM: x86: Suppress pending MMIO write exits if emulator detects exception
KVM: x86/ioapic: Resample the pending state of an IRQ when unmasking
KVM: irqfd: Make resampler_list an RCU list
KVM: SVM: Flush Hyper-V TLB when required
Initialization must be completed before calling _vdpa_register_device()
since it can connect the device to the vDPA bus, so requests can arrive
after that call.
So for example vdpasim_net_work(), which uses the net->*_stats variables,
can be scheduled before they are initialized.
Let's move _vdpa_register_device() to the end of vdpasim_net_dev_add()
and add a comment to avoid future issues.
Fixes: 0899774cb3 ("vdpa_sim_net: vendor satistics")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20230329160321.187176-1-sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
