mounting with sync not respected #12
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working on this now |
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that mount flag doesn't even seem to come through, we need to trace this to understand it better. |
ericvh
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Dec 17, 2022
We need to check if we have a OS prefix, otherwise we stumble on a
metric segv that I'm now seeing in Arnaldo's tree:
$ gdb --args perf stat -M Backend true
...
Performance counter stats for 'true':
4,712,355 TOPDOWN.SLOTS # 17.3 % tma_core_bound
Program received signal SIGSEGV, Segmentation fault.
__strlen_evex () at ../sysdeps/x86_64/multiarch/strlen-evex.S:77
77 ../sysdeps/x86_64/multiarch/strlen-evex.S: No such file or directory.
(gdb) bt
#0 __strlen_evex () at ../sysdeps/x86_64/multiarch/strlen-evex.S:77
#1 0x00007ffff74749a5 in __GI__IO_fputs (str=0x0, fp=0x7ffff75f5680 <_IO_2_1_stderr_>)
#2 0x0000555555779f28 in do_new_line_std (config=0x555555e077c0 <stat_config>, os=0x7fffffffbf10) at util/stat-display.c:356
#3 0x000055555577a081 in print_metric_std (config=0x555555e077c0 <stat_config>, ctx=0x7fffffffbf10, color=0x0, fmt=0x5555558b77b5 "%8.1f", unit=0x7fffffffbb10 "% tma_memory_bound", val=13.165355724442199) at util/stat-display.c:380
#4 0x00005555557768b6 in generic_metric (config=0x555555e077c0 <stat_config>, metric_expr=0x55555593d5b7 "((CYCLE_ACTIVITY.STALLS_MEM_ANY + EXE_ACTIVITY.BOUND_ON_STORES) / (CYCLE_ACTIVITY.STALLS_TOTAL + (EXE_ACTIVITY.1_PORTS_UTIL + tma_retiring * EXE_ACTIVITY.2_PORTS_UTIL) + EXE_ACTIVITY.BOUND_ON_STORES))"..., metric_events=0x555555f334e0, metric_refs=0x555555ec81d0, name=0x555555f32e80 "TOPDOWN.SLOTS", metric_name=0x555555f26c80 "tma_memory_bound", metric_unit=0x55555593d5b1 "100%", runtime=0, map_idx=0, out=0x7fffffffbd90, st=0x555555e9e620 <rt_stat>) at util/stat-shadow.c:934
#5 0x0000555555778cac in perf_stat__print_shadow_stats (config=0x555555e077c0 <stat_config>, evsel=0x555555f289d0, avg=4712355, map_idx=0, out=0x7fffffffbd90, metric_events=0x555555e078e8 <stat_config+296>, st=0x555555e9e620 <rt_stat>) at util/stat-shadow.c:1329
#6 0x000055555577b6a0 in printout (config=0x555555e077c0 <stat_config>, os=0x7fffffffbf10, uval=4712355, run=325322, ena=325322, noise=4712355, map_idx=0) at util/stat-display.c:741
#7 0x000055555577bc74 in print_counter_aggrdata (config=0x555555e077c0 <stat_config>, counter=0x555555f289d0, s=0, os=0x7fffffffbf10) at util/stat-display.c:838
#8 0x000055555577c1d8 in print_counter (config=0x555555e077c0 <stat_config>, counter=0x555555f289d0, os=0x7fffffffbf10) at util/stat-display.c:957
#9 0x000055555577dba0 in evlist__print_counters (evlist=0x555555ec3610, config=0x555555e077c0 <stat_config>, _target=0x555555e01c80 <target>, ts=0x0, argc=1, argv=0x7fffffffe450) at util/stat-display.c:1413
#10 0x00005555555fc821 in print_counters (ts=0x0, argc=1, argv=0x7fffffffe450) at builtin-stat.c:1040
#11 0x000055555560091a in cmd_stat (argc=1, argv=0x7fffffffe450) at builtin-stat.c:2665
#12 0x00005555556b1eea in run_builtin (p=0x555555e11f70 <commands+336>, argc=4, argv=0x7fffffffe450) at perf.c:322
#13 0x00005555556b2181 in handle_internal_command (argc=4, argv=0x7fffffffe450) at perf.c:376
#14 0x00005555556b22d7 in run_argv (argcp=0x7fffffffe27c, argv=0x7fffffffe270) at perf.c:420
#15 0x00005555556b26ef in main (argc=4, argv=0x7fffffffe450) at perf.c:550
(gdb)
Fixes: f123b2d ("perf stat: Remove prefix argument in print_metric_headers()")
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Link: http://lore.kernel.org/lkml/CAP-5=fUOjSM5HajU9TCD6prY39LbX4OQbkEbtKPPGRBPBN=_VQ@mail.gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
fixed 2aff6f9 |
ericvh
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Ido Schimmel says:
====================
bridge: mcast: Extensions for EVPN
tl;dr
=====
This patchset creates feature parity between user space and the kernel
and allows the former to install and replace MDB port group entries with
a source list and associated filter mode. This is required for EVPN use
cases where multicast state is not derived from snooped IGMP/MLD
packets, but instead derived from EVPN routes exchanged by the control
plane in user space.
Background
==========
IGMPv3 [1] and MLDv2 [2] differ from earlier versions of the protocols
in that they add support for source-specific multicast. That is, hosts
can advertise interest in listening to a particular multicast address
only from specific source addresses or from all sources except for
specific source addresses.
In kernel 5.10 [3][4], the bridge driver gained the ability to snoop
IGMPv3/MLDv2 packets and install corresponding MDB port group entries.
For example, a snooped IGMPv3 Membership Report that contains a single
MODE_IS_EXCLUDE record for group 239.10.10.10 with sources 192.0.2.1,
192.0.2.2, 192.0.2.20 and 192.0.2.21 would trigger the creation of these
entries:
# bridge -d mdb show
dev br0 port veth1 grp 239.10.10.10 src 192.0.2.21 temp filter_mode include proto kernel blocked
dev br0 port veth1 grp 239.10.10.10 src 192.0.2.20 temp filter_mode include proto kernel blocked
dev br0 port veth1 grp 239.10.10.10 src 192.0.2.2 temp filter_mode include proto kernel blocked
dev br0 port veth1 grp 239.10.10.10 src 192.0.2.1 temp filter_mode include proto kernel blocked
dev br0 port veth1 grp 239.10.10.10 temp filter_mode exclude source_list 192.0.2.21/0.00,192.0.2.20/0.00,192.0.2.2/0.00,192.0.2.1/0.00 proto kernel
While the kernel can install and replace entries with a filter mode and
source list, user space cannot. It can only add EXCLUDE entries with an
empty source list, which is sufficient for IGMPv2/MLDv1, but not for
IGMPv3/MLDv2.
Use cases where the multicast state is not derived from snooped packets,
but instead derived from routes exchanged by the user space control
plane require feature parity between user space and the kernel in terms
of MDB configuration. Such a use case is detailed in the next section.
Motivation
==========
RFC 7432 [5] defines a "MAC/IP Advertisement route" (type 2) [6] that
allows NVE switches in the EVPN network to advertise and learn
reachability information for unicast MAC addresses. Traffic destined to
a unicast MAC address can therefore be selectively forwarded to a single
NVE switch behind which the MAC is located.
The same is not true for IP multicast traffic. Such traffic is simply
flooded as BUM to all NVE switches in the broadcast domain (BD),
regardless if a switch has interested receivers for the multicast stream
or not. This is especially problematic for overlay networks that make
heavy use of multicast.
The issue is addressed by RFC 9251 [7] that defines a "Selective
Multicast Ethernet Tag Route" (type 6) [8] which allows NVE switches in
the EVPN network to advertise multicast streams that they are interested
in. This is done by having each switch suppress IGMP/MLD packets from
being transmitted to the NVE network and instead communicate the
information over BGP to other switches.
As far as the bridge driver is concerned, the above means that the
multicast state (i.e., {multicast address, group timer, filter-mode,
(source records)}) for the VXLAN bridge port is not populated by the
kernel from snooped IGMP/MLD packets (they are suppressed), but instead
by user space. Specifically, by the routing daemon that is exchanging
EVPN routes with other NVE switches.
Changes are obviously also required in the VXLAN driver, but they are
the subject of future patchsets. See the "Future work" section.
Implementation
==============
The user interface is extended to allow user space to specify the filter
mode of the MDB port group entry and its source list. Replace support is
also added so that user space would not need to remove an entry and
re-add it only to edit its source list or filter mode, as that would
result in packet loss. Example usage:
# bridge mdb replace dev br0 port dummy10 grp 239.1.1.1 permanent \
source_list 192.0.2.1,192.0.2.3 filter_mode exclude proto zebra
# bridge -d -s mdb show
dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.3 permanent filter_mode include proto zebra blocked 0.00
dev br0 port dummy10 grp 239.1.1.1 src 192.0.2.1 permanent filter_mode include proto zebra blocked 0.00
dev br0 port dummy10 grp 239.1.1.1 permanent filter_mode exclude source_list 192.0.2.3/0.00,192.0.2.1/0.00 proto zebra 0.00
The netlink interface is extended with a few new attributes in the
RTM_NEWMDB request message:
[ struct nlmsghdr ]
[ struct br_port_msg ]
[ MDBA_SET_ENTRY ]
struct br_mdb_entry
[ MDBA_SET_ENTRY_ATTRS ]
[ MDBE_ATTR_SOURCE ]
struct in_addr / struct in6_addr
[ MDBE_ATTR_SRC_LIST ] // new
[ MDBE_SRC_LIST_ENTRY ]
[ MDBE_SRCATTR_ADDRESS ]
struct in_addr / struct in6_addr
[ ...]
[ MDBE_ATTR_GROUP_MODE ] // new
u8
[ MDBE_ATTR_RTPORT ] // new
u8
No changes are required in RTM_NEWMDB responses and notifications, as
all the information can already be dumped by the kernel today.
Testing
=======
Tested with existing bridge multicast selftests: bridge_igmp.sh,
bridge_mdb_port_down.sh, bridge_mdb.sh, bridge_mld.sh,
bridge_vlan_mcast.sh.
In addition, added many new test cases for existing as well as for new
MDB functionality.
Patchset overview
=================
Patches #1-#8 are non-functional preparations for the core changes in
later patches.
Patches #9-#10 allow user space to install (*, G) entries with a source
list and associated filter mode. Specifically, patch #9 adds the
necessary kernel plumbing and patch #10 exposes the new functionality to
user space via a few new attributes.
Patch #11 allows user space to specify the routing protocol of new MDB
port group entries so that a routing daemon could differentiate between
entries installed by it and those installed by an administrator.
Patch #12 allows user space to replace MDB port group entries. This is
useful, for example, when user space wants to add a new source to a
source list. Instead of deleting a (*, G) entry and re-adding it with an
extended source list (which would result in packet loss), user space can
simply replace the current entry.
Patches #13-#14 add tests for existing MDB functionality as well as for
all new functionality added in this patchset.
Future work
===========
The VXLAN driver will need to be extended with an MDB so that it could
selectively forward IP multicast traffic to NVE switches with interested
receivers instead of simply flooding it to all switches as BUM.
The idea is to reuse the existing MDB interface for the VXLAN driver in
a similar way to how the FDB interface is shared between the bridge and
VXLAN drivers.
From command line perspective, configuration will look as follows:
# bridge mdb add dev br0 port vxlan0 grp 239.1.1.1 permanent \
filter_mode exclude source_list 198.50.100.1,198.50.100.2
# bridge mdb add dev vxlan0 port vxlan0 grp 239.1.1.1 permanent \
filter_mode include source_list 198.50.100.3,198.50.100.4 \
dst 192.0.2.1 dst_port 4789 src_vni 2
# bridge mdb add dev vxlan0 port vxlan0 grp 239.1.1.1 permanent \
filter_mode exclude source_list 198.50.100.1,198.50.100.2 \
dst 192.0.2.2 dst_port 4789 src_vni 2
Where the first command is enabled by this set, but the next two will be
the subject of future work.
From netlink perspective, the existing PF_BRIDGE/RTM_*MDB messages will
be extended to the VXLAN driver. This means that a few new attributes
will be added (e.g., 'MDBE_ATTR_SRC_VNI') and that the handlers for
these messages will need to move to net/core/rtnetlink.c. The rtnetlink
code will call into the appropriate driver based on the ifindex
specified in the ancillary header.
iproute2 patches can be found here [9].
Changelog
=========
Since v1 [10]:
* Patch #12: Remove extack from br_mdb_replace_group_sg().
* Patch #12: Change 'nlflags' to u16 and move it after 'filter_mode' to
pack the structure.
Since RFC [11]:
* Patch #6: New patch.
* Patch #9: Use an array instead of a list to store source entries.
* Patch #10: Use an array instead of list to store source entries.
* Patch #10: Drop br_mdb_config_attrs_fini().
* Patch #11: Reject protocol for host entries.
* Patch #13: New patch.
* Patch #14: New patch.
[1] https://datatracker.ietf.org/doc/html/rfc3376
[2] https://www.rfc-editor.org/rfc/rfc3810
[3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6af52ae2ed14a6bc756d5606b29097dfd76740b8
[4] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=68d4fd30c83b1b208e08c954cd45e6474b148c87
[5] https://datatracker.ietf.org/doc/html/rfc7432
[6] https://datatracker.ietf.org/doc/html/rfc7432#section-7.2
[7] https://datatracker.ietf.org/doc/html/rfc9251
[8] https://datatracker.ietf.org/doc/html/rfc9251#section-9.1
[9] https://github.com/idosch/iproute2/commits/submit/mdb_v1
[10] https://lore.kernel.org/netdev/20221208152839.1016350-1-idosch@nvidia.com/
[11] https://lore.kernel.org/netdev/20221018120420.561846-1-idosch@nvidia.com/
====================
Link: https://lore.kernel.org/r/20221210145633.1328511-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ericvh
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When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be dereferenced as wrong struct in irdma_free_pending_cqp_request(). PID: 3669 TASK: ffff88aef892c000 CPU: 28 COMMAND: "kworker/28:0" #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34 #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2 #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f #3 [fffffe0000549eb8] do_nmi at ffffffff81079582 #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4 [exception RIP: native_queued_spin_lock_slowpath+1291] RIP: ffffffff8127e72b RSP: ffff88aa841ef778 RFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88b01f849700 RCX: ffffffff8127e47e RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff83857ec0 RBP: ffff88afe3e4efc8 R8: ffffed15fc7c9dfa R9: ffffed15fc7c9dfa R10: 0000000000000001 R11: ffffed15fc7c9df9 R12: 0000000000740000 R13: ffff88b01f849708 R14: 0000000000000003 R15: ffffed1603f092e1 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 -- <NMI exception stack> -- #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4 #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363 #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma] #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma] #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma] #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma] #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6 #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278 #15 [ffff88aa841efb88] device_del at ffffffff82179d23 #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice] #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice] #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff #20 [ffff88aa841eff10] kthread at ffffffff811d87a0 #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions") Link: https://lore.kernel.org/r/20231130081415.891006-1-lishifeng@sangfor.com.cn Suggested-by: "Ismail, Mustafa" <mustafa.ismail@intel.com> Signed-off-by: Shifeng Li <lishifeng@sangfor.com.cn> Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
ericvh
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The helper, cxl_dpa_resource_start(), snapshots the dpa-address of an
endpoint-decoder after acquiring the cxl_dpa_rwsem. However, it is
sufficient to assert that cxl_dpa_rwsem is held rather than acquire it
in the helper. Otherwise, it triggers multiple lockdep reports:
1/ Tracing callbacks are in an atomic context that can not acquire sleeping
locks:
BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1525
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1288, name: bash
preempt_count: 2, expected: 0
RCU nest depth: 0, expected: 0
[..]
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS edk2-20230524-3.fc38 05/24/2023
Call Trace:
<TASK>
dump_stack_lvl+0x71/0x90
__might_resched+0x1b2/0x2c0
down_read+0x1a/0x190
cxl_dpa_resource_start+0x15/0x50 [cxl_core]
cxl_trace_hpa+0x122/0x300 [cxl_core]
trace_event_raw_event_cxl_poison+0x1c9/0x2d0 [cxl_core]
2/ The rwsem is already held in the inject poison path:
WARNING: possible recursive locking detected
6.7.0-rc2+ #12 Tainted: G W OE N
--------------------------------------------
bash/1288 is trying to acquire lock:
ffffffffc05f73d0 (cxl_dpa_rwsem){++++}-{3:3}, at: cxl_dpa_resource_start+0x15/0x50 [cxl_core]
but task is already holding lock:
ffffffffc05f73d0 (cxl_dpa_rwsem){++++}-{3:3}, at: cxl_inject_poison+0x7d/0x1e0 [cxl_core]
[..]
Call Trace:
<TASK>
dump_stack_lvl+0x71/0x90
__might_resched+0x1b2/0x2c0
down_read+0x1a/0x190
cxl_dpa_resource_start+0x15/0x50 [cxl_core]
cxl_trace_hpa+0x122/0x300 [cxl_core]
trace_event_raw_event_cxl_poison+0x1c9/0x2d0 [cxl_core]
__traceiter_cxl_poison+0x5c/0x80 [cxl_core]
cxl_inject_poison+0x1bc/0x1e0 [cxl_core]
This appears to have been an issue since the initial implementation and
uncovered by the new cxl-poison.sh test [1]. That test is now passing with
these changes.
Fixes: 28a3ae4 ("cxl/trace: Add an HPA to cxl_poison trace events")
Link: http://lore.kernel.org/r/e4f2716646918135ddbadf4146e92abb659de734.1700615159.git.alison.schofield@intel.com [1]
Cc: <stable@vger.kernel.org>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
ericvh
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Jan 25, 2024
nvif_vmm_put gets called if addr is set, but if the allocation fails we don't need to call put, otherwise we get a warning like [523232.435671] ------------[ cut here ]------------ [523232.435674] WARNING: CPU: 8 PID: 1505697 at drivers/gpu/drm/nouveau/nvif/vmm.c:68 nvif_vmm_put+0x72/0x80 [nouveau] [523232.435795] Modules linked in: uinput rfcomm snd_seq_dummy snd_hrtimer nf_conntrack_netbios_ns nf_conntrack_broadcast nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables nfnetlink qrtr bnep sunrpc binfmt_misc intel_rapl_msr intel_rapl_common intel_uncore_frequency intel_uncore_frequency_common isst_if_common iwlmvm nfit libnvdimm vfat fat x86_pkg_temp_thermal intel_powerclamp mac80211 snd_soc_avs snd_soc_hda_codec coretemp snd_hda_ext_core snd_soc_core snd_hda_codec_realtek kvm_intel snd_hda_codec_hdmi snd_compress snd_hda_codec_generic ac97_bus snd_pcm_dmaengine snd_hda_intel libarc4 snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec kvm iwlwifi snd_hda_core btusb snd_hwdep btrtl snd_seq btintel irqbypass btbcm rapl snd_seq_device eeepc_wmi btmtk intel_cstate iTCO_wdt cfg80211 snd_pcm asus_wmi bluetooth intel_pmc_bxt iTCO_vendor_support snd_timer ledtrig_audio pktcdvd snd mei_me [523232.435828] sparse_keymap intel_uncore i2c_i801 platform_profile wmi_bmof mei pcspkr ioatdma soundcore i2c_smbus rfkill idma64 dca joydev acpi_tad loop zram nouveau drm_ttm_helper ttm video drm_exec drm_gpuvm gpu_sched crct10dif_pclmul i2c_algo_bit nvme crc32_pclmul crc32c_intel drm_display_helper polyval_clmulni nvme_core polyval_generic e1000e mxm_wmi cec ghash_clmulni_intel r8169 sha512_ssse3 nvme_common wmi pinctrl_sunrisepoint uas usb_storage ip6_tables ip_tables fuse [523232.435849] CPU: 8 PID: 1505697 Comm: gnome-shell Tainted: G W 6.6.0-rc7-nvk-uapi+ #12 [523232.435851] Hardware name: System manufacturer System Product Name/ROG STRIX X299-E GAMING II, BIOS 1301 09/24/2021 [523232.435852] RIP: 0010:nvif_vmm_put+0x72/0x80 [nouveau] [523232.435934] Code: 00 00 48 89 e2 be 02 00 00 00 48 c7 04 24 00 00 00 00 48 89 44 24 08 e8 fc bf ff ff 85 c0 75 0a 48 c7 43 08 00 00 00 00 eb b3 <0f> 0b eb f2 e8 f5 c9 b2 e6 0f 1f 44 00 00 90 90 90 90 90 90 90 90 [523232.435936] RSP: 0018:ffffc900077ffbd8 EFLAGS: 00010282 [523232.435937] RAX: 00000000fffffffe RBX: ffffc900077ffc00 RCX: 0000000000000010 [523232.435938] RDX: 0000000000000010 RSI: ffffc900077ffb38 RDI: ffffc900077ffbd8 [523232.435940] RBP: ffff888e1c4f2140 R08: 0000000000000000 R09: 0000000000000000 [523232.435940] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888503811800 [523232.435941] R13: ffffc900077ffca0 R14: ffff888e1c4f2140 R15: ffff88810317e1e0 [523232.435942] FS: 00007f933a769640(0000) GS:ffff88905fa00000(0000) knlGS:0000000000000000 [523232.435943] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [523232.435944] CR2: 00007f930bef7000 CR3: 00000005d0322001 CR4: 00000000003706e0 [523232.435945] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [523232.435946] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [523232.435964] Call Trace: [523232.435965] <TASK> [523232.435966] ? nvif_vmm_put+0x72/0x80 [nouveau] [523232.436051] ? __warn+0x81/0x130 [523232.436055] ? nvif_vmm_put+0x72/0x80 [nouveau] [523232.436138] ? report_bug+0x171/0x1a0 [523232.436142] ? handle_bug+0x3c/0x80 [523232.436144] ? exc_invalid_op+0x17/0x70 [523232.436145] ? asm_exc_invalid_op+0x1a/0x20 [523232.436149] ? nvif_vmm_put+0x72/0x80 [nouveau] [523232.436230] ? nvif_vmm_put+0x64/0x80 [nouveau] [523232.436342] nouveau_vma_del+0x80/0xd0 [nouveau] [523232.436506] nouveau_vma_new+0x1a0/0x210 [nouveau] [523232.436671] nouveau_gem_object_open+0x1d0/0x1f0 [nouveau] [523232.436835] drm_gem_handle_create_tail+0xd1/0x180 [523232.436840] drm_prime_fd_to_handle_ioctl+0x12e/0x200 [523232.436844] ? __pfx_drm_prime_fd_to_handle_ioctl+0x10/0x10 [523232.436847] drm_ioctl_kernel+0xd3/0x180 [523232.436849] drm_ioctl+0x26d/0x4b0 [523232.436851] ? __pfx_drm_prime_fd_to_handle_ioctl+0x10/0x10 [523232.436855] nouveau_drm_ioctl+0x5a/0xb0 [nouveau] [523232.437032] __x64_sys_ioctl+0x94/0xd0 [523232.437036] do_syscall_64+0x5d/0x90 [523232.437040] ? syscall_exit_to_user_mode+0x2b/0x40 [523232.437044] ? do_syscall_64+0x6c/0x90 [523232.437046] entry_SYSCALL_64_after_hwframe+0x6e/0xd8 Reported-by: Faith Ekstrand <faith.ekstrand@collabora.com> Cc: stable@vger.kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240117213852.295565-1-airlied@gmail.com
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vhost_worker will call tun call backs to receive packets. If too many illegal packets arrives, tun_do_read will keep dumping packet contents. When console is enabled, it will costs much more cpu time to dump packet and soft lockup will be detected. net_ratelimit mechanism can be used to limit the dumping rate. PID: 33036 TASK: ffff949da6f20000 CPU: 23 COMMAND: "vhost-32980" #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e #3 [fffffe00003fced0] do_nmi at ffffffff8922660d #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663 [exception RIP: io_serial_in+20] RIP: ffffffff89792594 RSP: ffffa655314979e8 RFLAGS: 00000002 RAX: ffffffff89792500 RBX: ffffffff8af428a0 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000005 RDI: ffffffff8af428a0 RBP: 0000000000002710 R8: 0000000000000004 R9: 000000000000000f R10: 0000000000000000 R11: ffffffff8acbf64f R12: 0000000000000020 R13: ffffffff8acbf698 R14: 0000000000000058 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07 #12 [ffffa65531497b68] printk at ffffffff89318306 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun] #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun] #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net] #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost] #18 [ffffa65531497f10] kthread at ffffffff892d2e72 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors") Signed-off-by: Lei Chen <lei.chen@smartx.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Acked-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Commit 1548036 ("nfs: make the rpc_stat per net namespace") added functionality to specify rpc_stats function but missed adding it to the TCP TLS functionality. As the result, mounting with xprtsec=tls lead to the following kernel oops. [ 128.984192] Unable to handle kernel NULL pointer dereference at virtual address 000000000000001c [ 128.985058] Mem abort info: [ 128.985372] ESR = 0x0000000096000004 [ 128.985709] EC = 0x25: DABT (current EL), IL = 32 bits [ 128.986176] SET = 0, FnV = 0 [ 128.986521] EA = 0, S1PTW = 0 [ 128.986804] FSC = 0x04: level 0 translation fault [ 128.987229] Data abort info: [ 128.987597] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 128.988169] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 128.988811] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 128.989302] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000106c84000 [ 128.990048] [000000000000001c] pgd=0000000000000000, p4d=0000000000000000 [ 128.990736] Internal error: Oops: 0000000096000004 [#1] SMP [ 128.991168] Modules linked in: nfs_layout_nfsv41_files rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace netfs uinput dm_mod nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 rfkill ip_set nf_tables nfnetlink qrtr vsock_loopback vmw_vsock_virtio_transport_common vmw_vsock_vmci_transport vsock sunrpc vfat fat uvcvideo videobuf2_vmalloc videobuf2_memops uvc videobuf2_v4l2 videodev videobuf2_common mc vmw_vmci xfs libcrc32c e1000e crct10dif_ce ghash_ce sha2_ce vmwgfx nvme sha256_arm64 nvme_core sr_mod cdrom sha1_ce drm_ttm_helper ttm drm_kms_helper drm sg fuse [ 128.996466] CPU: 0 PID: 179 Comm: kworker/u4:26 Kdump: loaded Not tainted 6.8.0-rc6+ #12 [ 128.997226] Hardware name: VMware, Inc. VMware20,1/VBSA, BIOS VMW201.00V.21805430.BA64.2305221830 05/22/2023 [ 128.998084] Workqueue: xprtiod xs_tcp_tls_setup_socket [sunrpc] [ 128.998701] pstate: 81400005 (Nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) [ 128.999384] pc : call_start+0x74/0x138 [sunrpc] [ 128.999809] lr : __rpc_execute+0xb8/0x3e0 [sunrpc] [ 129.000244] sp : ffff8000832b3a00 [ 129.000508] x29: ffff8000832b3a00 x28: ffff800081ac79c0 x27: ffff800081ac7000 [ 129.001111] x26: 0000000004248060 x25: 0000000000000000 x24: ffff800081596008 [ 129.001757] x23: ffff80007b087240 x22: ffff00009a509d30 x21: 0000000000000000 [ 129.002345] x20: ffff000090075600 x19: ffff00009a509d00 x18: ffffffffffffffff [ 129.002912] x17: 733d4d4554535953 x16: 42555300312d746e x15: ffff8000832b3a88 [ 129.003464] x14: ffffffffffffffff x13: ffff8000832b3a7d x12: 0000000000000008 [ 129.004021] x11: 0101010101010101 x10: ffff8000150cb560 x9 : ffff80007b087c00 [ 129.004577] x8 : ffff00009a509de0 x7 : 0000000000000000 x6 : 00000000be8c4ee3 [ 129.005026] x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff000094d56680 [ 129.005425] x2 : ffff80007b0637f8 x1 : ffff000090075600 x0 : ffff00009a509d00 [ 129.005824] Call trace: [ 129.005967] call_start+0x74/0x138 [sunrpc] [ 129.006233] __rpc_execute+0xb8/0x3e0 [sunrpc] [ 129.006506] rpc_execute+0x160/0x1d8 [sunrpc] [ 129.006778] rpc_run_task+0x148/0x1f8 [sunrpc] [ 129.007204] tls_probe+0x80/0xd0 [sunrpc] [ 129.007460] rpc_ping+0x28/0x80 [sunrpc] [ 129.007715] rpc_create_xprt+0x134/0x1a0 [sunrpc] [ 129.007999] rpc_create+0x128/0x2a0 [sunrpc] [ 129.008264] xs_tcp_tls_setup_socket+0xdc/0x508 [sunrpc] [ 129.008583] process_one_work+0x174/0x3c8 [ 129.008813] worker_thread+0x2c8/0x3e0 [ 129.009033] kthread+0x100/0x110 [ 129.009225] ret_from_fork+0x10/0x20 [ 129.009432] Code: f0ffffc2 911fe042 aa1403e1 aa1303e0 (b9401c83) Fixes: 1548036 ("nfs: make the rpc_stat per net namespace") Signed-off-by: Olga Kornievskaia <kolga@netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
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syzkaller reported a warning [0] triggered while destroying immature netns. rpc_proc_register() was called in init_nfs_fs(), but its error has been ignored since at least the initial commit 1da177e ("Linux-2.6.12-rc2"). Recently, commit d47151b ("nfs: expose /proc/net/sunrpc/nfs in net namespaces") converted the procfs to per-netns and made the problem more visible. Even when rpc_proc_register() fails, nfs_net_init() could succeed, and thus nfs_net_exit() will be called while destroying the netns. Then, remove_proc_entry() will be called for non-existing proc directory and trigger the warning below. Let's handle the error of rpc_proc_register() properly in nfs_net_init(). [0]: name 'nfs' WARNING: CPU: 1 PID: 1710 at fs/proc/generic.c:711 remove_proc_entry+0x1bb/0x2d0 fs/proc/generic.c:711 Modules linked in: CPU: 1 PID: 1710 Comm: syz-executor.2 Not tainted 6.8.0-12822-gcd51db110a7e #12 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:remove_proc_entry+0x1bb/0x2d0 fs/proc/generic.c:711 Code: 41 5d 41 5e c3 e8 85 09 b5 ff 48 c7 c7 88 58 64 86 e8 09 0e 71 02 e8 74 09 b5 ff 4c 89 e6 48 c7 c7 de 1b 80 84 e8 c5 ad 97 ff <0f> 0b eb b1 e8 5c 09 b5 ff 48 c7 c7 88 58 64 86 e8 e0 0d 71 02 eb RSP: 0018:ffffc9000c6d7ce0 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff8880422b8b00 RCX: ffffffff8110503c RDX: ffff888030652f00 RSI: ffffffff81105045 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffffffff81bb62cb R12: ffffffff84807ffc R13: ffff88804ad6fcc0 R14: ffffffff84807ffc R15: ffffffff85741ff8 FS: 00007f30cfba8640(0000) GS:ffff88807dd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff51afe8000 CR3: 000000005a60a005 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> rpc_proc_unregister+0x64/0x70 net/sunrpc/stats.c:310 nfs_net_exit+0x1c/0x30 fs/nfs/inode.c:2438 ops_exit_list+0x62/0xb0 net/core/net_namespace.c:170 setup_net+0x46c/0x660 net/core/net_namespace.c:372 copy_net_ns+0x244/0x590 net/core/net_namespace.c:505 create_new_namespaces+0x2ed/0x770 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xae/0x160 kernel/nsproxy.c:228 ksys_unshare+0x342/0x760 kernel/fork.c:3322 __do_sys_unshare kernel/fork.c:3393 [inline] __se_sys_unshare kernel/fork.c:3391 [inline] __x64_sys_unshare+0x1f/0x30 kernel/fork.c:3391 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x4f/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x46/0x4e RIP: 0033:0x7f30d0febe5d Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 73 9f 1b 00 f7 d8 64 89 01 48 RSP: 002b:00007f30cfba7cc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00000000004bbf80 RCX: 00007f30d0febe5d RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006c020600 RBP: 00000000004bbf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 000000000000000b R14: 00007f30d104c530 R15: 0000000000000000 </TASK> Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
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With BPF_PROBE_MEM, BPF allows de-referencing an untrusted pointer. To
thwart invalid memory accesses, the JITs add an exception table entry
for all such accesses. But in case the src_reg + offset is a userspace
address, the BPF program might read that memory if the user has
mapped it.
Make the verifier add guard instructions around such memory accesses and
skip the load if the address falls into the userspace region.
The JITs need to implement bpf_arch_uaddress_limit() to define where
the userspace addresses end for that architecture or TASK_SIZE is taken
as default.
The implementation is as follows:
REG_AX = SRC_REG
if(offset)
REG_AX += offset;
REG_AX >>= 32;
if (REG_AX <= (uaddress_limit >> 32))
DST_REG = 0;
else
DST_REG = *(size *)(SRC_REG + offset);
Comparing just the upper 32 bits of the load address with the upper
32 bits of uaddress_limit implies that the values are being aligned down
to a 4GB boundary before comparison.
The above means that all loads with address <= uaddress_limit + 4GB are
skipped. This is acceptable because there is a large hole (much larger
than 4GB) between userspace and kernel space memory, therefore a
correctly functioning BPF program should not access this 4GB memory
above the userspace.
Let's analyze what this patch does to the following fentry program
dereferencing an untrusted pointer:
SEC("fentry/tcp_v4_connect")
int BPF_PROG(fentry_tcp_v4_connect, struct sock *sk)
{
*(volatile long *)sk;
return 0;
}
BPF Program before | BPF Program after
------------------ | -----------------
0: (79) r1 = *(u64 *)(r1 +0) 0: (79) r1 = *(u64 *)(r1 +0)
-----------------------------------------------------------------------
1: (79) r1 = *(u64 *)(r1 +0) --\ 1: (bf) r11 = r1
----------------------------\ \ 2: (77) r11 >>= 32
2: (b7) r0 = 0 \ \ 3: (b5) if r11 <= 0x8000 goto pc+2
3: (95) exit \ \-> 4: (79) r1 = *(u64 *)(r1 +0)
\ 5: (05) goto pc+1
\ 6: (b7) r1 = 0
\--------------------------------------
7: (b7) r0 = 0
8: (95) exit
As you can see from above, in the best case (off=0), 5 extra instructions
are emitted.
Now, we analyze the same program after it has gone through the JITs of
ARM64 and RISC-V architectures. We follow the single load instruction
that has the untrusted pointer and see what instrumentation has been
added around it.
x86-64 JIT
==========
JIT's Instrumentation
(upstream)
---------------------
0: nopl 0x0(%rax,%rax,1)
5: xchg %ax,%ax
7: push %rbp
8: mov %rsp,%rbp
b: mov 0x0(%rdi),%rdi
---------------------------------
f: movabs $0x800000000000,%r11
19: cmp %r11,%rdi
1c: jb 0x000000000000002a
1e: mov %rdi,%r11
21: add $0x0,%r11
28: jae 0x000000000000002e
2a: xor %edi,%edi
2c: jmp 0x0000000000000032
2e: mov 0x0(%rdi),%rdi
---------------------------------
32: xor %eax,%eax
34: leave
35: ret
The x86-64 JIT already emits some instructions to protect against user
memory access. This patch doesn't make any changes for the x86-64 JIT.
ARM64 JIT
=========
No Intrumentation Verifier's Instrumentation
(upstream) (This patch)
----------------- --------------------------
0: add x9, x30, #0x0 0: add x9, x30, #0x0
4: nop 4: nop
8: paciasp 8: paciasp
c: stp x29, x30, [sp, #-16]! c: stp x29, x30, [sp, #-16]!
10: mov x29, sp 10: mov x29, sp
14: stp x19, x20, [sp, #-16]! 14: stp x19, x20, [sp, #-16]!
18: stp x21, x22, [sp, #-16]! 18: stp x21, x22, [sp, #-16]!
1c: stp x25, x26, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]!
20: stp x27, x28, [sp, #-16]! 20: stp x27, x28, [sp, #-16]!
24: mov x25, sp 24: mov x25, sp
28: mov x26, #0x0 28: mov x26, #0x0
2c: sub x27, x25, #0x0 2c: sub x27, x25, #0x0
30: sub sp, sp, #0x0 30: sub sp, sp, #0x0
34: ldr x0, [x0] 34: ldr x0, [x0]
--------------------------------------------------------------------------------
38: ldr x0, [x0] ----------\ 38: add x9, x0, #0x0
-----------------------------------\\ 3c: lsr x9, x9, #32
3c: mov x7, #0x0 \\ 40: cmp x9, #0x10, lsl #12
40: mov sp, sp \\ 44: b.ls 0x0000000000000050
44: ldp x27, x28, [sp], #16 \\--> 48: ldr x0, [x0]
48: ldp x25, x26, [sp], #16 \ 4c: b 0x0000000000000054
4c: ldp x21, x22, [sp], #16 \ 50: mov x0, #0x0
50: ldp x19, x20, [sp], #16 \---------------------------------------
54: ldp x29, x30, [sp], #16 54: mov x7, #0x0
58: add x0, x7, #0x0 58: mov sp, sp
5c: autiasp 5c: ldp x27, x28, [sp], #16
60: ret 60: ldp x25, x26, [sp], #16
64: nop 64: ldp x21, x22, [sp], #16
68: ldr x10, 0x0000000000000070 68: ldp x19, x20, [sp], #16
6c: br x10 6c: ldp x29, x30, [sp], #16
70: add x0, x7, #0x0
74: autiasp
78: ret
7c: nop
80: ldr x10, 0x0000000000000088
84: br x10
There are 6 extra instructions added in ARM64 in the best case. This will
become 7 in the worst case (off != 0).
RISC-V JIT (RISCV_ISA_C Disabled)
==========
No Intrumentation Verifier's Instrumentation
(upstream) (This patch)
----------------- --------------------------
0: nop 0: nop
4: nop 4: nop
8: li a6, 33 8: li a6, 33
c: addi sp, sp, -16 c: addi sp, sp, -16
10: sd s0, 8(sp) 10: sd s0, 8(sp)
14: addi s0, sp, 16 14: addi s0, sp, 16
18: ld a0, 0(a0) 18: ld a0, 0(a0)
---------------------------------------------------------------
1c: ld a0, 0(a0) --\ 1c: mv t0, a0
--------------------------\ \ 20: srli t0, t0, 32
20: li a5, 0 \ \ 24: lui t1, 4096
24: ld s0, 8(sp) \ \ 28: sext.w t1, t1
28: addi sp, sp, 16 \ \ 2c: bgeu t1, t0, 12
2c: sext.w a0, a5 \ \--> 30: ld a0, 0(a0)
30: ret \ 34: j 8
\ 38: li a0, 0
\------------------------------
3c: li a5, 0
40: ld s0, 8(sp)
44: addi sp, sp, 16
48: sext.w a0, a5
4c: ret
There are 7 extra instructions added in RISC-V.
Fixes: 8008342 ("bpf, arm64: Add BPF exception tables")
Reported-by: Breno Leitao <leitao@debian.org>
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Link: https://lore.kernel.org/r/20240424100210.11982-2-puranjay@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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mount -o sync doesn't seem to inhibit writeback
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