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.
code
Clone this repository
https://tangled.org/tjh.dev/kernel
git@gordian.tjh.dev:tjh.dev/kernel
For self-hosted knots, clone URLs may differ based on your setup.
The cpu_emergency_register_virt_callback() function is used
unconditionally by the x86 kvm code, but it is declared (and defined)
conditionally:
#if IS_ENABLED(CONFIG_KVM_INTEL) || IS_ENABLED(CONFIG_KVM_AMD)
void cpu_emergency_register_virt_callback(cpu_emergency_virt_cb *callback);
...
leading to a build error when neither KVM_INTEL nor KVM_AMD support is
enabled:
arch/x86/kvm/x86.c: In function ‘kvm_arch_enable_virtualization’:
arch/x86/kvm/x86.c:12517:9: error: implicit declaration of function ‘cpu_emergency_register_virt_callback’ [-Wimplicit-function-declaration]
12517 | cpu_emergency_register_virt_callback(kvm_x86_ops.emergency_disable_virtualization_cpu);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/kvm/x86.c: In function ‘kvm_arch_disable_virtualization’:
arch/x86/kvm/x86.c:12522:9: error: implicit declaration of function ‘cpu_emergency_unregister_virt_callback’ [-Wimplicit-function-declaration]
12522 | cpu_emergency_unregister_virt_callback(kvm_x86_ops.emergency_disable_virtualization_cpu);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Fix the build by defining empty helper functions the same way the old
cpu_emergency_disable_virtualization() function was dealt with for the
same situation.
Maybe we could instead have made the call sites conditional, since the
callers (kvm_arch_{en,dis}able_virtualization()) have an empty weak
fallback. I'll leave that to the kvm people to argue about, this at
least gets the build going for that particular config.
Fixes: 590b09b1d88e ("KVM: x86: Register "emergency disable" callbacks when virt is enabled")
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Kai Huang <kai.huang@intel.com>
Cc: Chao Gao <chao.gao@intel.com>
Cc: Farrah Chen <farrah.chen@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull mailbox updates from Jassi Brar:
- fix kconfig dependencies (mhu-v3, omap2+)
- use devie name instead of genereic imx_mu_chan as interrupt name
(imx)
- enable sa8255p and qcs8300 ipc controllers (qcom)
- Fix timeout during suspend mode (bcm2835)
- convert to use use of_property_match_string (mailbox)
- enable mt8188 (mediatek)
- use devm_clk_get_enabled helpers (spreadtrum)
- fix device-id typo (rockchip)
* tag 'mailbox-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jassibrar/mailbox:
mailbox, remoteproc: omap2+: fix compile testing
dt-bindings: mailbox: qcom-ipcc: Document QCS8300 IPCC
dt-bindings: mailbox: qcom-ipcc: document the support for SA8255p
dt-bindings: mailbox: mtk,adsp-mbox: Add compatible for MT8188
mailbox: Use of_property_match_string() instead of open-coding
mailbox: bcm2835: Fix timeout during suspend mode
mailbox: sprd: Use devm_clk_get_enabled() helpers
mailbox: rockchip: fix a typo in module autoloading
mailbox: imx: use device name in interrupt name
mailbox: ARM_MHU_V3 should depend on ARM64
Pull i2c fixes from Wolfram Sang:
- fix DesignWare driver ENABLE-ABORT sequence, ensuring ABORT can
always be sent when needed
- check for PCLK in the SynQuacer controller as an optional clock,
allowing ACPI to directly provide the clock rate
- KEBA driver Kconfig dependency fix
- fix XIIC driver power suspend sequence
* tag 'i2c-for-6.12-rc1-additional_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: xiic: Fix pm_runtime_set_suspended() with runtime pm enabled
i2c: keba: I2C_KEBA should depend on KEBA_CP500
i2c: synquacer: Deal with optional PCLK correctly
i2c: designware: fix controller is holding SCL low while ENABLE bit is disabled
Selecting CONFIG_OMAP2PLUS_MBOX while compile testing
causes a build failure:
WARNING: unmet direct dependencies detected for OMAP2PLUS_MBOX
Depends on [n]: MAILBOX [=y] && (ARCH_OMAP2PLUS || ARCH_K3)
Selected by [m]:
- TI_K3_M4_REMOTEPROC [=m] && REMOTEPROC [=y] && (ARCH_K3 || COMPILE_TEST [=y])
Using 'select' to force-enable another subsystem is generally
a mistake and causes problems such as this one, so change the
three drivers that link against this driver to use 'depends on'
instead, and ensure the driver itself can be compile tested
regardless of the platform.
When compile-testing without CONFIG_TI_SCI_PROTOCOL=m, there
is a chance for a link failure, so add a careful dependency
on that.
arm-linux-gnueabi-ld: drivers/remoteproc/ti_k3_m4_remoteproc.o: in function `k3_m4_rproc_probe':
ti_k3_m4_remoteproc.c:(.text.k3_m4_rproc_probe+0x76): undefined reference to `devm_ti_sci_get_by_phandle'
Fixes: ebcf9008a895 ("remoteproc: k3-m4: Add a remoteproc driver for M4F subsystem")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Andrew Davis <afd@ti.com>
Reviewed-by: Martyn Welch <martyn.welch@collabora.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Pull dma-mapping fix from Christoph Hellwig:
- handle chained SGLs in the new tracing code (Christoph Hellwig)
* tag 'dma-mapping-6.12-2024-09-29' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: fix DMA API tracing for chained scatterlists
I2C host fixes for v6.12-rc1
The DesignWare driver now has the correct ENABLE-ABORT sequence,
ensuring ABORT can always be sent when needed.
In the SynQuacer controller we now check for PCLK as an optional
clock, allowing ACPI to directly provide the clock rate.
The recent KEBA driver required a dependency fix in Kconfig.
The XIIC driver now has a corrected power suspend sequence.
Document the Inter-Processor Communication Controller on the Qualcomm
QCS8300 Platform, which will be used to route interrupts across various
subsystems found on the SoC.
Signed-off-by: Jingyi Wang <quic_jingyw@quicinc.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Pull more SCSI updates from James Bottomley:
"These are mostly minor updates.
There are two drivers (lpfc and mpi3mr) which missed the initial
pull and a core change to retry a start/stop unit which affect
suspend/resume"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (32 commits)
scsi: lpfc: Update lpfc version to 14.4.0.5
scsi: lpfc: Support loopback tests with VMID enabled
scsi: lpfc: Revise TRACE_EVENT log flag severities from KERN_ERR to KERN_WARNING
scsi: lpfc: Ensure DA_ID handling completion before deleting an NPIV instance
scsi: lpfc: Fix kref imbalance on fabric ndlps from dev_loss_tmo handler
scsi: lpfc: Restrict support for 32 byte CDBs to specific HBAs
scsi: lpfc: Update phba link state conditional before sending CMF_SYNC_WQE
scsi: lpfc: Add ELS_RSP cmd to the list of WQEs to flush in lpfc_els_flush_cmd()
scsi: mpi3mr: Update driver version to 8.12.0.0.50
scsi: mpi3mr: Improve wait logic while controller transitions to READY state
scsi: mpi3mr: Update MPI Headers to revision 34
scsi: mpi3mr: Use firmware-provided timestamp update interval
scsi: mpi3mr: Enhance the Enable Controller retry logic
scsi: sd: Fix off-by-one error in sd_read_block_characteristics()
scsi: pm8001: Do not overwrite PCI queue mapping
scsi: scsi_debug: Remove a useless memset()
scsi: pmcraid: Convert comma to semicolon
scsi: sd: Retry START STOP UNIT commands
scsi: mpi3mr: A performance fix
scsi: ufs: qcom: Update MODE_MAX cfg_bw value
...
scatterlist allocations can be chained, and thus all iterations need to
use the chain-aware iterators. Switch the newly added tracing to use the
proper iterators so that they work with chained scatterlists.
Fixes: 038eb433dc14 ("dma-mapping: add tracing for dma-mapping API calls")
Reported-by: syzbot+95e4ef83a3024384ec7a@syzkaller.appspotmail.com
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sean Anderson <sean.anderson@linux.dev>
Tested-by: syzbot+95e4ef83a3024384ec7a@syzkaller.appspotmail.com
Pull SoC update from Arnd Bergmann:
"Convert ep93xx to devicetree
This concludes a long journey towards replacing the old board files
with devictree description on the Cirrus Logic EP93xx platform.
Nikita Shubin has been working on this for a long time, for details
see the last post on
https://lore.kernel.org/lkml/20240909-ep93xx-v12-0-e86ab2423d4b@maquefel.me/"
* tag 'soc-ep93xx-dt-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (47 commits)
dt-bindings: gpio: ep9301: Add missing "#interrupt-cells" to examples
MAINTAINERS: Update EP93XX ARM ARCHITECTURE maintainer
soc: ep93xx: drop reference to removed EP93XX_SOC_COMMON config
net: cirrus: use u8 for addr to calm down sparse
dmaengine: cirrus: use snprintf() to calm down gcc 13.3.0
dmaengine: ep93xx: Fix a NULL vs IS_ERR() check in probe()
pinctrl: ep93xx: Fix raster pins typo
spi: ep93xx: update kerneldoc comments for ep93xx_spi
clk: ep93xx: Fix off by one in ep93xx_div_recalc_rate()
clk: ep93xx: add module license
dmaengine: cirrus: remove platform code
ASoC: cirrus: edb93xx: Delete driver
ARM: ep93xx: soc: drop defines
ARM: ep93xx: delete all boardfiles
ata: pata_ep93xx: remove legacy pinctrl use
pwm: ep93xx: drop legacy pinctrl
ARM: ep93xx: DT for the Cirrus ep93xx SoC platforms
ARM: dts: ep93xx: Add EDB9302 DT
ARM: dts: ep93xx: add ts7250 board
ARM: dts: add Cirrus EP93XX SoC .dtsi
...
It is not valid to call pm_runtime_set_suspended() for devices
with runtime PM enabled because it returns -EAGAIN if it is enabled
already and working. So, call pm_runtime_disable() before to fix it.
Fixes: 36ecbcab84d0 ("i2c: xiic: Implement power management")
Cc: <stable@vger.kernel.org> # v4.6+
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Add a compatible for the ipcc on SA8255p platforms.
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Nikunj Kela <quic_nkela@quicinc.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Pull more bcachefs updates from Kent Overstreet:
"Assorted minor syzbot fixes, and for bigger stuff:
Fix two disk accounting rewrite bugs:
- Disk accounting keys use the version field of bkey so that journal
replay can tell which updates have been applied to the btree.
This is set in the transaction commit path, after we've gotten our
journal reservation (and our time ordering), but the
BCH_TRANS_COMMIT_skip_accounting_apply flag that journal replay
uses was incorrectly skipping this for new updates generated prior
to journal replay.
This fixes the underlying cause of an assertion pop in
disk_accounting_read.
- A couple of fixes for disk accounting + device removal.
Checking if acocunting replicas entries were marked in the
superblock was being done at the wrong point, when deltas in the
journal could still zero them out, and then additionally we'd try
to add a missing replicas entry to the superblock without checking
if it referred to an invalid (removed) device.
A whole slew of repair fixes:
- fix infinite loop in propagate_key_to_snapshot_leaves(), this fixes
an infinite loop when repairing a filesystem with many snapshots
- fix incorrect transaction restart handling leading to occasional
"fsck counted ..." warnings
- fix warning in __bch2_fsck_err() for bkey fsck errors
- check_inode() in fsck now correctly checks if the filesystem was
clean
- there shouldn't be pending logged ops if the fs was clean, we now
check for this
- remove_backpointer() doesn't remove a dirent that doesn't actually
point to the inode
- many more fsck errors are AUTOFIX"
* tag 'bcachefs-2024-09-28' of git://evilpiepirate.org/bcachefs: (35 commits)
bcachefs: check_subvol_path() now prints subvol root inode
bcachefs: remove_backpointer() now checks if dirent points to inode
bcachefs: dirent_points_to_inode() now warns on mismatch
bcachefs: Fix lost wake up
bcachefs: Check for logged ops when clean
bcachefs: BCH_FS_clean_recovery
bcachefs: Convert disk accounting BUG_ON() to WARN_ON()
bcachefs: Fix BCH_TRANS_COMMIT_skip_accounting_apply
bcachefs: Check for accounting keys with bversion=0
bcachefs: rename version -> bversion
bcachefs: Don't delete unlinked inodes before logged op resume
bcachefs: Fix BCH_SB_ERRS() so we can reorder
bcachefs: Fix fsck warnings from bkey validation
bcachefs: Move transaction commit path validation to as late as possible
bcachefs: Fix disk accounting attempting to mark invalid replicas entry
bcachefs: Fix unlocked access to c->disk_sb.sb in bch2_replicas_entry_validate()
bcachefs: Fix accounting read + device removal
bcachefs: bch_accounting_mode
bcachefs: fix transaction restart handling in check_extents(), check_dirents()
bcachefs: kill inode_walker_entry.seen_this_pos
...
Justin Tee <justintee8345@gmail.com> says:
Update lpfc to revision 14.4.0.5
This patch set contains bug fixes related to HBA state clean ups, FCP
discovery on older adapters, kref imbalances, log message improvements,
and support for a new diagnostic loopback testing mode.
The patches were cut against Martin's 6.12/scsi-queue tree.
Link: https://lore.kernel.org/r/20240912232447.45607-1-justintee8345@gmail.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
While using the IOMMU DMA path, the dma_addressing_limited() function
checks ops struct which doesn't exist in the IOMMU case. This causes
to the kernel panic while loading ADMGPU driver.
BUG: kernel NULL pointer dereference, address: 00000000000000a0
PGD 0 P4D 0
Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 10 UID: 0 PID: 611 Comm: (udev-worker) Tainted: G T 6.11.0-clang-07154-g726e2d0cf2bb #257
Tainted: [T]=RANDSTRUCT
Hardware name: ASUS System Product Name/ROG STRIX Z690-G GAMING WIFI, BIOS 3701 07/03/2024
RIP: 0010:dma_addressing_limited+0x53/0xa0
Code: 8b 93 48 02 00 00 48 39 d1 49 89 d6 4c 0f 42 f1 48 85 d2 4c 0f 44 f1 f6 83 fc 02 00 00 40 75 0a 48 89 df e8 1f 09 00 00 eb 24 <4c> 8b 1c 25 a0 00 00 00 4d 85 db 74 17 48 89 df 41 ba 8b 84 2d 55
RSP: 0018:ffffa8d2c12cf740 EFLAGS: 00010202
RAX: 00000000ffffffff RBX: ffff8948820220c8 RCX: 000000ffffffffff
RDX: 0000000000000000 RSI: ffffffffc124dc6d RDI: ffff8948820220c8
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff894883c3f040
R13: ffff89488dac8828 R14: 000000ffffffffff R15: ffff8948820220c8
FS: 00007fe6ba881900(0000) GS:ffff894fdf700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000a0 CR3: 0000000111984000 CR4: 0000000000f50ef0
PKRU: 55555554
Call Trace:
<TASK>
? __die_body+0x65/0xc0
? page_fault_oops+0x3b9/0x450
? _prb_read_valid+0x212/0x390
? do_user_addr_fault+0x608/0x680
? exc_page_fault+0x4e/0xa0
? asm_exc_page_fault+0x26/0x30
? dma_addressing_limited+0x53/0xa0
amdgpu_ttm_init+0x56/0x4b0 [amdgpu]
gmc_v8_0_sw_init+0x561/0x670 [amdgpu]
amdgpu_device_ip_init+0xf5/0x570 [amdgpu]
amdgpu_device_init+0x1a57/0x1ea0 [amdgpu]
? _raw_spin_unlock_irqrestore+0x1a/0x40
? pci_conf1_read+0xc0/0xe0
? pci_bus_read_config_word+0x52/0xa0
amdgpu_driver_load_kms+0x15/0xa0 [amdgpu]
amdgpu_pci_probe+0x1b7/0x4c0 [amdgpu]
pci_device_probe+0x1c5/0x260
really_probe+0x130/0x470
__driver_probe_device+0x77/0x150
driver_probe_device+0x19/0x120
__driver_attach+0xb1/0x1e0
? __cfi___driver_attach+0x10/0x10
bus_for_each_dev+0x115/0x170
bus_add_driver+0x192/0x2d0
driver_register+0x5c/0xf0
? __cfi_init_module+0x10/0x10 [amdgpu]
do_one_initcall+0x128/0x380
? idr_alloc_cyclic+0x139/0x1d0
? security_kernfs_init_security+0x42/0x140
? __kernfs_new_node+0x1be/0x250
? sysvec_apic_timer_interrupt+0xb6/0xc0
? asm_sysvec_apic_timer_interrupt+0x1a/0x20
? _raw_spin_unlock+0x11/0x30
? free_unref_page+0x283/0x650
? kfree+0x274/0x3a0
? kfree+0x274/0x3a0
? kfree+0x274/0x3a0
? load_module+0xf2e/0x1130
? __kmalloc_cache_noprof+0x12a/0x2e0
do_init_module+0x7d/0x240
__se_sys_init_module+0x19e/0x220
do_syscall_64+0x8a/0x150
? __irq_exit_rcu+0x5e/0x100
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fe6bb5980ee
Code: 48 8b 0d 3d ed 12 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 af 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 0a ed 12 00 f7 d8 64 89 01 48
RSP: 002b:00007ffd462219d8 EFLAGS: 00000206 ORIG_RAX: 00000000000000af
RAX: ffffffffffffffda RBX: 0000556caf0d0670 RCX: 00007fe6bb5980ee
RDX: 0000556caf0d3080 RSI: 0000000002893458 RDI: 00007fe6b3400010
RBP: 0000000000020000 R08: 0000000000020010 R09: 0000000000000080
R10: c26073c166186e00 R11: 0000000000000206 R12: 0000556caf0d3430
R13: 0000556caf0d0670 R14: 0000556caf0d3080 R15: 0000556caf0ce700
</TASK>
Modules linked in: amdgpu(+) i915(+) drm_suballoc_helper intel_gtt drm_exec drm_buddy iTCO_wdt i2c_algo_bit intel_pmc_bxt drm_display_helper iTCO_vendor_support gpu_sched drm_ttm_helper cec ttm amdxcp video backlight pinctrl_alderlake nct6775 hwmon_vid nct6775_core coretemp
CR2: 00000000000000a0
---[ end trace 0000000000000000 ]---
RIP: 0010:dma_addressing_limited+0x53/0xa0
Code: 8b 93 48 02 00 00 48 39 d1 49 89 d6 4c 0f 42 f1 48 85 d2 4c 0f 44 f1 f6 83 fc 02 00 00 40 75 0a 48 89 df e8 1f 09 00 00 eb 24 <4c> 8b 1c 25 a0 00 00 00 4d 85 db 74 17 48 89 df 41 ba 8b 84 2d 55
RSP: 0018:ffffa8d2c12cf740 EFLAGS: 00010202
RAX: 00000000ffffffff RBX: ffff8948820220c8 RCX: 000000ffffffffff
RDX: 0000000000000000 RSI: ffffffffc124dc6d RDI: ffff8948820220c8
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff894883c3f040
R13: ffff89488dac8828 R14: 000000ffffffffff R15: ffff8948820220c8
FS: 00007fe6ba881900(0000) GS:ffff894fdf700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000a0 CR3: 0000000111984000 CR4: 0000000000f50ef0
PKRU: 55555554
Fixes: b5c58b2fdc42 ("dma-mapping: direct calls for dma-iommu")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219292
Reported-by: Niklāvs Koļesņikovs <pinkflames.linux@gmail.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Niklāvs Koļesņikovs <pinkflames.linux@gmail.com>