kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-11-10 20:48:12 +00:00
Code Issues Releases Packages Activity
No description
1,311,447 commits 117 branches 5,827 tags 6.3 GiB
  • C 96.8%
  • Assembly 0.9%
  • Rust 0.7%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Tvrtko Ursulin ec6de20f2e drm/v3d: Appease lockdep while updating GPU stats 
[ Upstream commit 06c3c40685 ]

Lockdep thinks our seqcount_t usage is unsafe because the update path can
be both from irq and worker context:

 [ ] ================================
 [ ] WARNING: inconsistent lock state
 [ ] 6.10.3-v8-16k-numa #159 Tainted: G        WC
 [ ] --------------------------------
 [ ] inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
 [ ] swapper/0/0 [HC1[1]:SC0[0]:HE0:SE1] takes:
 [ ] ffff80003d7c08d0 (&v3d_priv->stats[i].lock){?.+.}-{0:0}, at: v3d_irq+0xc8/0x660 [v3d]
 [ ] {HARDIRQ-ON-W} state was registered at:
 [ ]   lock_acquire+0x1f8/0x328
 [ ]   v3d_job_start_stats.isra.0+0xd8/0x218 [v3d]
 [ ]   v3d_bin_job_run+0x23c/0x388 [v3d]
 [ ]   drm_sched_run_job_work+0x520/0x6d0 [gpu_sched]
 [ ]   process_one_work+0x62c/0xb48
 [ ]   worker_thread+0x468/0x5b0
 [ ]   kthread+0x1c4/0x1e0
 [ ]   ret_from_fork+0x10/0x20
 [ ] irq event stamp: 337094
 [ ] hardirqs last  enabled at (337093): [<ffffc0008144ce7c>] default_idle_call+0x11c/0x140
 [ ] hardirqs last disabled at (337094): [<ffffc0008144a354>] el1_interrupt+0x24/0x58
 [ ] softirqs last  enabled at (337082): [<ffffc00080061d90>] handle_softirqs+0x4e0/0x538
 [ ] softirqs last disabled at (337073): [<ffffc00080010364>] __do_softirq+0x1c/0x28
 [ ]
                other info that might help us debug this:
 [ ]  Possible unsafe locking scenario:

 [ ]        CPU0
 [ ]        ----
 [ ]   lock(&v3d_priv->stats[i].lock);
 [ ]   <Interrupt>
 [ ]     lock(&v3d_priv->stats[i].lock);
 [ ]
                *** DEADLOCK ***

 [ ] no locks held by swapper/0/0.
 [ ]
               stack backtrace:
 [ ] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        WC         6.10.3-v8-16k-numa #159
 [ ] Hardware name: Raspberry Pi 5 Model B Rev 1.0 (DT)
 [ ] Call trace:
 [ ]  dump_backtrace+0x170/0x1b8
 [ ]  show_stack+0x20/0x38
 [ ]  dump_stack_lvl+0xb4/0xd0
 [ ]  dump_stack+0x18/0x28
 [ ]  print_usage_bug+0x3cc/0x3f0
 [ ]  mark_lock+0x4d0/0x968
 [ ]  __lock_acquire+0x784/0x18c8
 [ ]  lock_acquire+0x1f8/0x328
 [ ]  v3d_job_update_stats+0xec/0x2e0 [v3d]
 [ ]  v3d_irq+0xc8/0x660 [v3d]
 [ ]  __handle_irq_event_percpu+0x1f8/0x488
 [ ]  handle_irq_event+0x88/0x128
 [ ]  handle_fasteoi_irq+0x298/0x408
 [ ]  generic_handle_domain_irq+0x50/0x78

But it is a false positive because all the queue-stats pairs have their
own lock and jobs are also one at a time.

Nevertheless we can appease lockdep by disabling local interrupts to make
it see lock usage is consistent.

Cc: Maíra Canal <mcanal@igalia.com>
Fixes: 6abe93b621 ("drm/v3d: Fix race-condition between sysfs/fdinfo and interrupt handler")
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Signed-off-by: Maíra Canal <mcanal@igalia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240813102505.80512-2-tursulin@igalia.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2024-12-05 14:01:37 +01:00
arch arm64: dts: rockchip: correct analog audio name on Indiedroid Nova 2024-12-05 14:01:35 +01:00
block block: fix bio_split_rw_at to take zone_write_granularity into account 2024-12-05 14:01:14 +01:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: pcrypt - Call crypto layer directly when padata_do_parallel() return -EBUSY 2024-12-05 14:01:18 +01:00
Documentation dt-bindings: cache: qcom,llcc: Fix X1E80100 reg entries 2024-12-05 14:01:32 +01:00
drivers drm/v3d: Appease lockdep while updating GPU stats 2024-12-05 14:01:37 +01:00
fs ext4: fix race in buffer_head read fault injection 2024-12-05 14:01:15 +01:00
include platform/x86/intel/pmt: allow user offset for PMT callbacks 2024-12-05 14:01:35 +01:00
init initramfs: avoid filename buffer overrun 2024-12-05 14:01:12 +01:00
io_uring io_uring/rw: fix missing NOWAIT check for O_DIRECT start write 2024-10-31 08:21:02 -06:00
ipc struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
kernel sched_ext: scx_bpf_dispatch_from_dsq_set_*() are allowed from unlocked context 2024-12-05 14:01:35 +01:00
lib objpool: fix to make percpu slot allocation more robust 2024-11-07 14:14:58 -08:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm mm/mmap: fix __mmap_region() error handling in rare merge failure case 2024-11-22 15:30:26 +01:00
net hv_sock: Initializing vsk->trans to NULL to prevent a dangling pointer 2024-11-22 15:30:25 +01:00
rust rust: helpers: Avoid raw_spin_lock initialization for PREEMPT_RT 2024-12-05 14:01:23 +01:00
samples Including fixes from bluetooth. 2024-11-14 10:05:33 -08:00
scripts kernel-doc: allow object-like macros in ReST output 2024-12-05 14:01:28 +01:00
security integrity-v6.12 2024-11-12 13:06:31 -08:00
sound ASoC: Fixes for v6.12 2024-11-14 16:40:15 +01:00
tools selftests/resctrl: Protect against array overrun during iMC config parsing 2024-12-05 14:01:33 +01:00
usr initramfs: shorten cmd_initfs in usr/Makefile 2024-07-16 01:07:52 +09:00
virt ARM64: 2024-10-21 11:22:04 -07:00
.clang-format clang-format: Update with v6.11-rc1's for_each macro list 2024-08-02 13:20:31 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Kbuild updates for v6.12 2024-09-24 13:02:06 -07:00
.mailmap mailmap: add entry for Thorsten Blum 2024-11-07 14:14:59 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Remove self from DSA entry 2024-11-03 12:52:38 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: appoint myself the XFS maintainer for 6.12 LTS 2024-12-05 14:01:10 +01:00
Makefile Linux 6.12.1 2024-11-22 15:30:26 +01:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

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 reStructuredText 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.