| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: Defer sub-object cleanup in export put callbacks
svc_export_put() calls path_put() and auth_domain_put() immediately
when the last reference drops, before the RCU grace period. RCU
readers in e_show() and c_show() access both ex_path (via
seq_path/d_path) and ex_client->name (via seq_escape) without
holding a reference. If cache_clean removes the entry and drops the
last reference concurrently, the sub-objects are freed while still
in use, producing a NULL pointer dereference in d_path.
Commit 2530766492ec ("nfsd: fix UAF when access ex_uuid or
ex_stats") moved kfree of ex_uuid and ex_stats into the
call_rcu callback, but left path_put() and auth_domain_put() running
before the grace period because both may sleep and call_rcu
callbacks execute in softirq context.
Replace call_rcu/kfree_rcu with queue_rcu_work(), which defers the
callback until after the RCU grace period and executes it in process
context where sleeping is permitted. This allows path_put() and
auth_domain_put() to be moved into the deferred callback alongside
the other resource releases. Apply the same fix to expkey_put(),
which has the identical pattern with ek_path and ek_client.
A dedicated workqueue scopes the shutdown drain to only NFSD
export release work items; flushing the shared
system_unbound_wq would stall on unrelated work from other
subsystems. nfsd_export_shutdown() uses rcu_barrier() followed
by flush_workqueue() to ensure all deferred release callbacks
complete before the export caches are destroyed.
Reviwed-by: Jeff Layton <jlayton@kernel.org> |
| In the Linux kernel, the following vulnerability has been resolved:
media: dvb-net: fix OOB access in ULE extension header tables
The ule_mandatory_ext_handlers[] and ule_optional_ext_handlers[] tables
in handle_one_ule_extension() are declared with 255 elements (valid
indices 0-254), but the index htype is derived from network-controlled
data as (ule_sndu_type & 0x00FF), giving a range of 0-255. When
htype equals 255, an out-of-bounds read occurs on the function pointer
table, and the OOB value may be called as a function pointer.
Add a bounds check on htype against the array size before either table
is accessed. Out-of-range values now cause the SNDU to be discarded. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: add missing netlink policy validations
Hyunwoo Kim reports out-of-bounds access in sctp and ctnetlink.
These attributes are used by the kernel without any validation.
Extend the netlink policies accordingly.
Quoting the reporter:
nlattr_to_sctp() assigns the user-supplied CTA_PROTOINFO_SCTP_STATE
value directly to ct->proto.sctp.state without checking that it is
within the valid range. [..]
and: ... with exp->dir = 100, the access at
ct->master->tuplehash[100] reads 5600 bytes past the start of a
320-byte nf_conn object, causing a slab-out-of-bounds read confirmed by
UBSAN. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: SCO: Fix use-after-free in sco_recv_frame() due to missing sock_hold
sco_recv_frame() reads conn->sk under sco_conn_lock() but immediately
releases the lock without holding a reference to the socket. A concurrent
close() can free the socket between the lock release and the subsequent
sk->sk_state access, resulting in a use-after-free.
Other functions in the same file (sco_sock_timeout(), sco_conn_del())
correctly use sco_sock_hold() to safely hold a reference under the lock.
Fix by using sco_sock_hold() to take a reference before releasing the
lock, and adding sock_put() on all exit paths. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: use volume UUID in FS_OBJECT_ID_INFORMATION
Use sb->s_uuid for a proper volume identifier as the primary choice.
For filesystems that do not provide a UUID, fall back to stfs.f_fsid
obtained from vfs_statfs(). |
| In the Linux kernel, the following vulnerability has been resolved:
net: mvpp2: guard flow control update with global_tx_fc in buffer switching
mvpp2_bm_switch_buffers() unconditionally calls
mvpp2_bm_pool_update_priv_fc() when switching between per-cpu and
shared buffer pool modes. This function programs CM3 flow control
registers via mvpp2_cm3_read()/mvpp2_cm3_write(), which dereference
priv->cm3_base without any NULL check.
When the CM3 SRAM resource is not present in the device tree (the
third reg entry added by commit 60523583b07c ("dts: marvell: add CM3
SRAM memory to cp11x ethernet device tree")), priv->cm3_base remains
NULL and priv->global_tx_fc is false. Any operation that triggers
mvpp2_bm_switch_buffers(), for example an MTU change that crosses
the jumbo frame threshold, will crash:
Unable to handle kernel NULL pointer dereference at
virtual address 0000000000000000
Mem abort info:
ESR = 0x0000000096000006
EC = 0x25: DABT (current EL), IL = 32 bits
pc : readl+0x0/0x18
lr : mvpp2_cm3_read.isra.0+0x14/0x20
Call trace:
readl+0x0/0x18
mvpp2_bm_pool_update_fc+0x40/0x12c
mvpp2_bm_pool_update_priv_fc+0x94/0xd8
mvpp2_bm_switch_buffers.isra.0+0x80/0x1c0
mvpp2_change_mtu+0x140/0x380
__dev_set_mtu+0x1c/0x38
dev_set_mtu_ext+0x78/0x118
dev_set_mtu+0x48/0xa8
dev_ifsioc+0x21c/0x43c
dev_ioctl+0x2d8/0x42c
sock_ioctl+0x314/0x378
Every other flow control call site in the driver already guards
hardware access with either priv->global_tx_fc or port->tx_fc.
mvpp2_bm_switch_buffers() is the only place that omits this check.
Add the missing priv->global_tx_fc guard to both the disable and
re-enable calls in mvpp2_bm_switch_buffers(), consistent with the
rest of the driver. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_conntrack_sip: fix Content-Length u32 truncation in sip_help_tcp()
sip_help_tcp() parses the SIP Content-Length header with
simple_strtoul(), which returns unsigned long, but stores the result in
unsigned int clen. On 64-bit systems, values exceeding UINT_MAX are
silently truncated before computing the SIP message boundary.
For example, Content-Length 4294967328 (2^32 + 32) is truncated to 32,
causing the parser to miscalculate where the current message ends. The
loop then treats trailing data in the TCP segment as a second SIP
message and processes it through the SDP parser.
Fix this by changing clen to unsigned long to match the return type of
simple_strtoul(), and reject Content-Length values that exceed the
remaining TCP payload length. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: HIDP: Fix possible UAF
This fixes the following trace caused by not dropping l2cap_conn
reference when user->remove callback is called:
[ 97.809249] l2cap_conn_free: freeing conn ffff88810a171c00
[ 97.809907] CPU: 1 UID: 0 PID: 1419 Comm: repro_standalon Not tainted 7.0.0-rc1-dirty #14 PREEMPT(lazy)
[ 97.809935] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014
[ 97.809947] Call Trace:
[ 97.809954] <TASK>
[ 97.809961] dump_stack_lvl (lib/dump_stack.c:122)
[ 97.809990] l2cap_conn_free (net/bluetooth/l2cap_core.c:1808)
[ 97.810017] l2cap_conn_del (./include/linux/kref.h:66 net/bluetooth/l2cap_core.c:1821 net/bluetooth/l2cap_core.c:1798)
[ 97.810055] l2cap_disconn_cfm (net/bluetooth/l2cap_core.c:7347 (discriminator 1) net/bluetooth/l2cap_core.c:7340 (discriminator 1))
[ 97.810086] ? __pfx_l2cap_disconn_cfm (net/bluetooth/l2cap_core.c:7341)
[ 97.810117] hci_conn_hash_flush (./include/net/bluetooth/hci_core.h:2152 (discriminator 2) net/bluetooth/hci_conn.c:2644 (discriminator 2))
[ 97.810148] hci_dev_close_sync (net/bluetooth/hci_sync.c:5360)
[ 97.810180] ? __pfx_hci_dev_close_sync (net/bluetooth/hci_sync.c:5285)
[ 97.810212] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 97.810242] ? up_write (./arch/x86/include/asm/atomic64_64.h:87 (discriminator 5) ./include/linux/atomic/atomic-arch-fallback.h:2852 (discriminator 5) ./include/linux/atomic/atomic-long.h:268 (discriminator 5) ./include/linux/atomic/atomic-instrumented.h:3391 (discriminator 5) kernel/locking/rwsem.c:1385 (discriminator 5) kernel/locking/rwsem.c:1643 (discriminator 5))
[ 97.810267] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 97.810290] ? rcu_is_watching (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/context_tracking.h:128 kernel/rcu/tree.c:752)
[ 97.810320] hci_unregister_dev (net/bluetooth/hci_core.c:504 net/bluetooth/hci_core.c:2716)
[ 97.810346] vhci_release (drivers/bluetooth/hci_vhci.c:691)
[ 97.810375] ? __pfx_vhci_release (drivers/bluetooth/hci_vhci.c:678)
[ 97.810404] __fput (fs/file_table.c:470)
[ 97.810430] task_work_run (kernel/task_work.c:235)
[ 97.810451] ? __pfx_task_work_run (kernel/task_work.c:201)
[ 97.810472] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 97.810495] ? do_raw_spin_unlock (./include/asm-generic/qspinlock.h:128 (discriminator 5) kernel/locking/spinlock_debug.c:142 (discriminator 5))
[ 97.810527] do_exit (kernel/exit.c:972)
[ 97.810547] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 97.810574] ? __pfx_do_exit (kernel/exit.c:897)
[ 97.810594] ? lock_acquire (kernel/locking/lockdep.c:470 (discriminator 6) kernel/locking/lockdep.c:5870 (discriminator 6) kernel/locking/lockdep.c:5825 (discriminator 6))
[ 97.810616] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 97.810639] ? do_raw_spin_lock (kernel/locking/spinlock_debug.c:95 (discriminator 4) kernel/locking/spinlock_debug.c:118 (discriminator 4))
[ 97.810664] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 97.810688] ? find_held_lock (kernel/locking/lockdep.c:5350 (discriminator 1))
[ 97.810721] do_group_exit (kernel/exit.c:1093)
[ 97.810745] get_signal (kernel/signal.c:3007 (discriminator 1))
[ 97.810772] ? security_file_permission (./arch/x86/include/asm/jump_label.h:37 security/security.c:2366)
[ 97.810803] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 97.810826] ? vfs_read (fs/read_write.c:555)
[ 97.810854] ? __pfx_get_signal (kernel/signal.c:2800)
[ 97.810880] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 97.810905] ? __pfx_vfs_read (fs/read_write.c:555)
[ 97.810932] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 97.810960] arch_do_signal_or_restart (arch/
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
igc: fix page fault in XDP TX timestamps handling
If an XDP application that requested TX timestamping is shutting down
while the link of the interface in use is still up the following kernel
splat is reported:
[ 883.803618] [ T1554] BUG: unable to handle page fault for address: ffffcfb6200fd008
...
[ 883.803650] [ T1554] Call Trace:
[ 883.803652] [ T1554] <TASK>
[ 883.803654] [ T1554] igc_ptp_tx_tstamp_event+0xdf/0x160 [igc]
[ 883.803660] [ T1554] igc_tsync_interrupt+0x2d5/0x300 [igc]
...
During shutdown of the TX ring the xsk_meta pointers are left behind, so
that the IRQ handler is trying to touch them.
This issue is now being fixed by cleaning up the stale xsk meta data on
TX shutdown. TX timestamps on other queues remain unaffected. |
| In the Linux kernel, the following vulnerability has been resolved:
ACPI: processor: Fix previous acpi_processor_errata_piix4() fix
After commi f132e089fe89 ("ACPI: processor: Fix NULL-pointer dereference
in acpi_processor_errata_piix4()"), device pointers may be dereferenced
after dropping references to the device objects pointed to by them,
which may cause a use-after-free to occur.
Moreover, debug messages about enabling the errata may be printed
if the errata flags corresponding to them are unset.
Address all of these issues by moving message printing to the points
in the code where the errata flags are set. |
| In the Linux kernel, the following vulnerability has been resolved:
ip_tunnel: adapt iptunnel_xmit_stats() to NETDEV_PCPU_STAT_DSTATS
Blamed commits forgot that vxlan/geneve use udp_tunnel[6]_xmit_skb() which
call iptunnel_xmit_stats().
iptunnel_xmit_stats() was assuming tunnels were only using
NETDEV_PCPU_STAT_TSTATS.
@syncp offset in pcpu_sw_netstats and pcpu_dstats is different.
32bit kernels would either have corruptions or freezes if the syncp
sequence was overwritten.
This patch also moves pcpu_stat_type closer to dev->{t,d}stats to avoid
a potential cache line miss since iptunnel_xmit_stats() needs to read it. |
| In the Linux kernel, the following vulnerability has been resolved:
arm_mpam: Fix null pointer dereference when restoring bandwidth counters
When an MSC supporting memory bandwidth monitoring is brought offline and
then online, mpam_restore_mbwu_state() calls __ris_msmon_read() via ipi to
restore the configuration of the bandwidth counters. It doesn't care about
the value read, mbwu_arg.val, and doesn't set it leading to a null pointer
dereference when __ris_msmon_read() adds to it. This results in a kernel
oops with a call trace such as:
Call trace:
__ris_msmon_read+0x19c/0x64c (P)
mpam_restore_mbwu_state+0xa0/0xe8
smp_call_on_cpu_callback+0x1c/0x38
process_one_work+0x154/0x4b4
worker_thread+0x188/0x310
kthread+0x11c/0x130
ret_from_fork+0x10/0x20
Provide a local variable for val to avoid __ris_msmon_read() dereferencing
a null pointer when adding to val. |
| In the Linux kernel, the following vulnerability has been resolved:
net: mana: fix use-after-free in mana_hwc_destroy_channel() by reordering teardown
A potential race condition exists in mana_hwc_destroy_channel() where
hwc->caller_ctx is freed before the HWC's Completion Queue (CQ) and
Event Queue (EQ) are destroyed. This allows an in-flight CQ interrupt
handler to dereference freed memory, leading to a use-after-free or
NULL pointer dereference in mana_hwc_handle_resp().
mana_smc_teardown_hwc() signals the hardware to stop but does not
synchronize against IRQ handlers already executing on other CPUs. The
IRQ synchronization only happens in mana_hwc_destroy_cq() via
mana_gd_destroy_eq() -> mana_gd_deregister_irq(). Since this runs
after kfree(hwc->caller_ctx), a concurrent mana_hwc_rx_event_handler()
can dereference freed caller_ctx (and rxq->msg_buf) in
mana_hwc_handle_resp().
Fix this by reordering teardown to reverse-of-creation order: destroy
the TX/RX work queues and CQ/EQ before freeing hwc->caller_ctx. This
ensures all in-flight interrupt handlers complete before the memory they
access is freed. |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: add NULL checks for idev in SRv6 paths
__in6_dev_get() can return NULL when the device has no IPv6 configuration
(e.g. MTU < IPV6_MIN_MTU or after NETDEV_UNREGISTER).
Add NULL checks for idev returned by __in6_dev_get() in both
seg6_hmac_validate_skb() and ipv6_srh_rcv() to prevent potential NULL
pointer dereferences. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case
In decode_int(), the CONS case calls get_bits(bs, 2) to read a length
value, then calls get_uint(bs, len) without checking that len bytes
remain in the buffer. The existing boundary check only validates the
2 bits for get_bits(), not the subsequent 1-4 bytes that get_uint()
reads. This allows a malformed H.323/RAS packet to cause a 1-4 byte
slab-out-of-bounds read.
Add a boundary check for len bytes after get_bits() and before
get_uint(). |
| In the Linux kernel, the following vulnerability has been resolved:
net: usb: cdc_ncm: add ndpoffset to NDP32 nframes bounds check
The same bounds-check bug fixed for NDP16 in the previous patch also
exists in cdc_ncm_rx_verify_ndp32(). The DPE array size is validated
against the total skb length without accounting for ndpoffset, allowing
out-of-bounds reads when the NDP32 is placed near the end of the NTB.
Add ndpoffset to the nframes bounds check and use struct_size_t() to
express the NDP-plus-DPE-array size more clearly.
Compile-tested only. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free of share_conf in compound request
smb2_get_ksmbd_tcon() reuses work->tcon in compound requests without
validating tcon->t_state. ksmbd_tree_conn_lookup() checks t_state ==
TREE_CONNECTED on the initial lookup path, but the compound reuse path
bypasses this check entirely.
If a prior command in the compound (SMB2_TREE_DISCONNECT) sets t_state
to TREE_DISCONNECTED and frees share_conf via ksmbd_share_config_put(),
subsequent commands dereference the freed share_conf through
work->tcon->share_conf.
KASAN report:
[ 4.144653] ==================================================================
[ 4.145059] BUG: KASAN: slab-use-after-free in smb2_write+0xc74/0xe70
[ 4.145415] Read of size 4 at addr ffff88810430c194 by task kworker/1:1/44
[ 4.145772]
[ 4.145867] CPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted 7.0.0-rc3+ #60 PREEMPTLAZY
[ 4.145871] Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 4.145875] Workqueue: ksmbd-io handle_ksmbd_work
[ 4.145888] Call Trace:
[ 4.145892] <TASK>
[ 4.145894] dump_stack_lvl+0x64/0x80
[ 4.145910] print_report+0xce/0x660
[ 4.145919] ? __pfx__raw_spin_lock_irqsave+0x10/0x10
[ 4.145928] ? smb2_write+0xc74/0xe70
[ 4.145931] kasan_report+0xce/0x100
[ 4.145934] ? smb2_write+0xc74/0xe70
[ 4.145937] smb2_write+0xc74/0xe70
[ 4.145939] ? __pfx_smb2_write+0x10/0x10
[ 4.145942] ? _raw_spin_unlock+0xe/0x30
[ 4.145945] ? ksmbd_smb2_check_message+0xeb2/0x24c0
[ 4.145948] ? smb2_tree_disconnect+0x31c/0x480
[ 4.145951] handle_ksmbd_work+0x40f/0x1080
[ 4.145953] process_one_work+0x5fa/0xef0
[ 4.145962] ? assign_work+0x122/0x3e0
[ 4.145964] worker_thread+0x54b/0xf70
[ 4.145967] ? __pfx_worker_thread+0x10/0x10
[ 4.145970] kthread+0x346/0x470
[ 4.145976] ? recalc_sigpending+0x19b/0x230
[ 4.145980] ? __pfx_kthread+0x10/0x10
[ 4.145984] ret_from_fork+0x4fb/0x6c0
[ 4.145992] ? __pfx_ret_from_fork+0x10/0x10
[ 4.145995] ? __switch_to+0x36c/0xbe0
[ 4.145999] ? __pfx_kthread+0x10/0x10
[ 4.146003] ret_from_fork_asm+0x1a/0x30
[ 4.146013] </TASK>
[ 4.146014]
[ 4.149858] Allocated by task 44:
[ 4.149953] kasan_save_stack+0x33/0x60
[ 4.150061] kasan_save_track+0x14/0x30
[ 4.150169] __kasan_kmalloc+0x8f/0xa0
[ 4.150274] ksmbd_share_config_get+0x1dd/0xdd0
[ 4.150401] ksmbd_tree_conn_connect+0x7e/0x600
[ 4.150529] smb2_tree_connect+0x2e6/0x1000
[ 4.150645] handle_ksmbd_work+0x40f/0x1080
[ 4.150761] process_one_work+0x5fa/0xef0
[ 4.150873] worker_thread+0x54b/0xf70
[ 4.150978] kthread+0x346/0x470
[ 4.151071] ret_from_fork+0x4fb/0x6c0
[ 4.151176] ret_from_fork_asm+0x1a/0x30
[ 4.151286]
[ 4.151332] Freed by task 44:
[ 4.151418] kasan_save_stack+0x33/0x60
[ 4.151526] kasan_save_track+0x14/0x30
[ 4.151634] kasan_save_free_info+0x3b/0x60
[ 4.151751] __kasan_slab_free+0x43/0x70
[ 4.151861] kfree+0x1ca/0x430
[ 4.151952] __ksmbd_tree_conn_disconnect+0xc8/0x190
[ 4.152088] smb2_tree_disconnect+0x1cd/0x480
[ 4.152211] handle_ksmbd_work+0x40f/0x1080
[ 4.152326] process_one_work+0x5fa/0xef0
[ 4.152438] worker_thread+0x54b/0xf70
[ 4.152545] kthread+0x346/0x470
[ 4.152638] ret_from_fork+0x4fb/0x6c0
[ 4.152743] ret_from_fork_asm+0x1a/0x30
[ 4.152853]
[ 4.152900] The buggy address belongs to the object at ffff88810430c180
[ 4.152900] which belongs to the cache kmalloc-96 of size 96
[ 4.153226] The buggy address is located 20 bytes inside of
[ 4.153226] freed 96-byte region [ffff88810430c180, ffff88810430c1e0)
[ 4.153549]
[ 4.153596] The buggy address belongs to the physical page:
[ 4.153750] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88810430ce80 pfn:0x10430c
[ 4.154000] flags: 0x
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
HID: bpf: prevent buffer overflow in hid_hw_request
right now the returned value is considered to be always valid. However,
when playing with HID-BPF, the return value can be arbitrary big,
because it's the return value of dispatch_hid_bpf_raw_requests(), which
calls the struct_ops and we have no guarantees that the value makes
sense. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: log new dentries when logging parent dir of a conflicting inode
If we log the parent directory of a conflicting inode, we are not logging
the new dentries of the directory, so when we finish we have the parent
directory's inode marked as logged but we did not log its new dentries.
As a consequence if the parent directory is explicitly fsynced later and
it does not have any new changes since we logged it, the fsync is a no-op
and after a power failure the new dentries are missing.
Example scenario:
$ mkdir foo
$ sync
$rmdir foo
$ mkdir dir1
$ mkdir dir2
# A file with the same name and parent as the directory we just deleted
# and was persisted in a past transaction. So the deleted directory's
# inode is a conflicting inode of this new file's inode.
$ touch foo
$ ln foo dir2/link
# The fsync on dir2 will log the parent directory (".") because the
# conflicting inode (deleted directory) does not exists anymore, but it
# it does not log its new dentries (dir1).
$ xfs_io -c "fsync" dir2
# This fsync on the parent directory is no-op, since the previous fsync
# logged it (but without logging its new dentries).
$ xfs_io -c "fsync" .
<power failure>
# After log replay dir1 is missing.
Fix this by ensuring we log new dir dentries whenever we log the parent
directory of a no longer existing conflicting inode.
A test case for fstests will follow soon. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/i915/dmc: Fix an unlikely NULL pointer deference at probe
intel_dmc_update_dc6_allowed_count() oopses when DMC hasn't been
initialized, and dmc is thus NULL.
That would be the case when the call path is
intel_power_domains_init_hw() -> {skl,bxt,icl}_display_core_init() ->
gen9_set_dc_state() -> intel_dmc_update_dc6_allowed_count(), as
intel_power_domains_init_hw() is called *before* intel_dmc_init().
However, gen9_set_dc_state() calls intel_dmc_update_dc6_allowed_count()
conditionally, depending on the current and target DC states. At probe,
the target is disabled, but if DC6 is enabled, the function is called,
and an oops follows. Apparently it's quite unlikely that DC6 is enabled
at probe, as we haven't seen this failure mode before.
It is also strange to have DC6 enabled at boot, since that would require
the DMC firmware (loaded by BIOS); the BIOS loading the DMC firmware and
the driver stopping / reprogramming the firmware is a poorly specified
sequence and as such unlikely an intentional BIOS behaviour. It's more
likely that BIOS is leaving an unintentionally enabled DC6 HW state
behind (without actually loading the required DMC firmware for this).
The tracking of the DC6 allowed counter only works if starting /
stopping the counter depends on the _SW_ DC6 state vs. the current _HW_
DC6 state (since stopping the counter requires the DC5 counter captured
when the counter was started). Thus, using the HW DC6 state is incorrect
and it also leads to the above oops. Fix both issues by using the SW DC6
state for the tracking.
This is v2 of the fix originally sent by Jani, updated based on the
first Link: discussion below.
(cherry picked from commit 2344b93af8eb5da5d496b4e0529d35f0f559eaf0) |
