Kernel Source and devicetree for NOTHING Phone(3a) and Phone(3a)Pro
Find a file
Cristian Marussi 7f95f6997f firmware: arm_scmi: Check mailbox/SMT channel for consistency
commit 437a310b22244d4e0b78665c3042e5d1c0f45306 upstream.

On reception of a completion interrupt the shared memory area is accessed
to retrieve the message header at first and then, if the message sequence
number identifies a transaction which is still pending, the related
payload is fetched too.

When an SCMI command times out the channel ownership remains with the
platform until eventually a late reply is received and, as a consequence,
any further transmission attempt remains pending, waiting for the channel
to be relinquished by the platform.

Once that late reply is received the channel ownership is given back
to the agent and any pending request is then allowed to proceed and
overwrite the SMT area of the just delivered late reply; then the wait
for the reply to the new request starts.

It has been observed that the spurious IRQ related to the late reply can
be wrongly associated with the freshly enqueued request: when that happens
the SCMI stack in-flight lookup procedure is fooled by the fact that the
message header now present in the SMT area is related to the new pending
transaction, even though the real reply has still to arrive.

This race-condition on the A2P channel can be detected by looking at the
channel status bits: a genuine reply from the platform will have set the
channel free bit before triggering the completion IRQ.

Add a consistency check to validate such condition in the A2P ISR.

Reported-by: Xinglong Yang <xinglong.yang@cixtech.com>
Closes: https://lore.kernel.org/all/PUZPR06MB54981E6FA00D82BFDBB864FBF08DA@PUZPR06MB5498.apcprd06.prod.outlook.com/
Fixes: 5c8a47a5a9 ("firmware: arm_scmi: Make scmi core independent of the transport type")
Cc: stable@vger.kernel.org # 5.15+
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Tested-by: Xinglong Yang <xinglong.yang@cixtech.com>
Link: https://lore.kernel.org/r/20231220172112.763539-1-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-31 16:17:08 -08:00
arch LoongArch/smp: Call rcutree_report_cpu_starting() earlier 2024-01-31 16:17:03 -08:00
block block: Remove special-casing of compound pages 2024-01-25 15:27:52 -08:00
certs certs: Fix build error when PKCS#11 URI contains semicolon 2023-02-09 11:28:11 +01:00
crypto crypto: api - Disallow identical driver names 2024-01-31 16:16:58 -08:00
Documentation rename(): fix the locking of subdirectories 2024-01-31 16:17:02 -08:00
drivers firmware: arm_scmi: Check mailbox/SMT channel for consistency 2024-01-31 16:17:08 -08:00
fs ksmbd: fix global oob in ksmbd_nl_policy 2024-01-31 16:17:07 -08:00
include btrfs: defrag: reject unknown flags of btrfs_ioctl_defrag_range_args 2024-01-31 16:17:07 -08:00
init rootfs: Fix support for rootfstype= when root= is given 2024-01-25 15:27:43 -08:00
io_uring io_uring/rw: ensure io->bytes_done is always initialized 2024-01-25 15:27:41 -08:00
ipc ipc: fix memory leak in init_mqueue_fs() 2022-12-31 13:32:01 +01:00
kernel rcu: Defer RCU kthreads wakeup when CPU is dying 2024-01-31 16:17:05 -08:00
lib kunit: debugfs: Fix unchecked dereference in debugfs_print_results() 2024-01-25 15:27:21 -08:00
LICENSES
mm mm: page_alloc: unreserve highatomic page blocks before oom 2024-01-31 16:17:03 -08:00
net netfilter: nf_tables: reject QUEUE/DROP verdict parameters 2024-01-31 16:17:07 -08:00
rust rust: allocator: Prevent mis-aligned allocation 2023-08-11 12:08:18 +02:00
samples fprobe: Pass entry_data to handlers 2023-10-25 12:03:12 +02:00
scripts scripts/get_abi: fix source path leak 2024-01-31 16:17:01 -08:00
security lsm: new security_file_ioctl_compat() hook 2024-01-31 16:17:00 -08:00
sound ASoC: mediatek: sof-common: Add NULL check for normal_link string 2024-01-25 15:27:48 -08:00
tools selftests: netdevsim: fix the udp_tunnel_nic test 2024-01-31 16:17:06 -08:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt kvm/vfio: ensure kvg instance stays around in kvm_vfio_group_add() 2023-09-13 09:42:46 +02:00
.clang-format inet: ping: use hlist_nulls rcu iterator during lookup 2022-12-01 12:42:46 +01:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes
.gitignore Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
.mailmap 9 hotfixes. 6 for MM, 3 for other areas. Four of these patches address 2022-12-10 17:10:52 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING
CREDITS MAINTAINERS: Remove Michal Marek from Kbuild maintainers 2022-11-16 14:53:00 +09:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig
MAINTAINERS genirq/affinity: Move group_cpus_evenly() into lib/ 2024-01-10 17:10:33 +01:00
Makefile Linux 6.1.75 2024-01-25 15:27:52 -08:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.