tjh.dev
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.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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.
Pull ARM SoC fixes from Arnd Bergmann:
"A number of fixes have accumulated, but they are largely for harmless
issues:
- Several OF node leak fixes
- A fix to the Exynos7885 UART clock description
- DTS fixes to prevent boot failures on TI AM64 and J721s2
- Bus probe error handling fixes for Baikal-T1
- A fixup to the way STM32 SoCs use separate dts files for different
firmware stacks
- Multiple code fixes for Arm SCMI firmware, all dealing with
robustness of the implementation
- Multiple NXP i.MX devicetree fixes, addressing incorrect data in DT
nodes
- Three updates to the MAINTAINERS file, including Florian Fainelli
taking over BCM283x/BCM2711 (Raspberry Pi) from Nicolas Saenz
Julienne"
* tag 'soc-fixes-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (29 commits)
ARM: dts: aspeed: nuvia: rename vendor nuvia to qcom
arm: mach-spear: Add missing of_node_put() in time.c
ARM: cns3xxx: Fix refcount leak in cns3xxx_init
MAINTAINERS: Update email address
arm64: dts: ti: k3-am64-main: Remove support for HS400 speed mode
arm64: dts: ti: k3-j721s2: Fix overlapping GICD memory region
ARM: dts: bcm2711-rpi-400: Fix GPIO line names
bus: bt1-axi: Don't print error on -EPROBE_DEFER
bus: bt1-apb: Don't print error on -EPROBE_DEFER
ARM: Fix refcount leak in axxia_boot_secondary
ARM: dts: stm32: move SCMI related nodes in a dedicated file for stm32mp15
soc: imx: imx8m-blk-ctrl: fix display clock for LCDIF2 power domain
ARM: dts: imx6qdl-colibri: Fix capacitive touch reset polarity
ARM: dts: imx6qdl: correct PU regulator ramp delay
firmware: arm_scmi: Fix incorrect error propagation in scmi_voltage_descriptors_get
firmware: arm_scmi: Avoid using extended string-buffers sizes if not necessary
firmware: arm_scmi: Fix SENSOR_AXIS_NAME_GET behaviour when unsupported
ARM: dts: imx7: Move hsic_phy power domain to HSIC PHY node
soc: bcm: brcmstb: pm: pm-arm: Fix refcount leak in brcmstb_pm_probe
MAINTAINERS: Update BCM2711/BCM2835 maintainer
...
Pull hotfixes from Andrew Morton:
"Minor things, mainly - mailmap updates, MAINTAINERS updates, etc.
Fixes for this merge window:
- fix for a damon boot hang, from SeongJae
- fix for a kfence warning splat, from Jason Donenfeld
- fix for zero-pfn pinning, from Alex Williamson
- fix for fallocate hole punch clearing, from Mike Kravetz
Fixes for previous releases:
- fix for a performance regression, from Marcelo
- fix for a hwpoisining BUG from zhenwei pi"
* tag 'mm-hotfixes-stable-2022-06-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mailmap: add entry for Christian Marangi
mm/memory-failure: disable unpoison once hw error happens
hugetlbfs: zero partial pages during fallocate hole punch
mm: memcontrol: reference to tools/cgroup/memcg_slabinfo.py
mm: re-allow pinning of zero pfns
mm/kfence: select random number before taking raw lock
MAINTAINERS: add maillist information for LoongArch
MAINTAINERS: update MM tree references
MAINTAINERS: update Abel Vesa's email
MAINTAINERS: add MEMORY HOT(UN)PLUG section and add David as reviewer
MAINTAINERS: add Miaohe Lin as a memory-failure reviewer
mailmap: add alias for jarkko@profian.com
mm/damon/reclaim: schedule 'damon_reclaim_timer' only after 'system_wq' is initialized
kthread: make it clear that kthread_create_on_node() might be terminated by any fatal signal
mm: lru_cache_disable: use synchronize_rcu_expedited
mm/page_isolation.c: fix one kernel-doc comment
Nuvia has been acquired by Qualcomm and the vendor name 'nuvia' will
not be used anymore so rename aspeed-bmc-nuvia-dc-scm.dts to
aspeed-bmc-qcom-dc-scm-v1.dts and change 'nuvia' to 'qcom' as its vendor
name in the file.
Fixes: 7b46aa7c008d ("ARM: dts: aspeed: Add Nuvia DC-SCM BMC")
Signed-off-by: Jae Hyun Yoo <quic_jaehyoo@quicinc.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20220523175640.60155-1-quic_jaehyoo@quicinc.com
Link: https://lore.kernel.org/r/20220624070511.4070659-1-joel@jms.id.au'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Enable ignore_missing_thread in 'perf stat', enabling counting with
'--pid' when threads disappear during counting session setup
- Adjust output data offset for backward compatibility in 'perf inject'
- Fix missing free in copy_kcore_dir() in 'perf inject'
- Fix caching files with a wrong build ID
- Sync drm, cpufeatures, vhost and svn headers with the kernel
* tag 'perf-tools-fixes-for-v5.19-2022-06-26' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
tools headers UAPI: Synch KVM's svm.h header with the kernel
tools include UAPI: Sync linux/vhost.h with the kernel sources
perf stat: Enable ignore_missing_thread
perf inject: Adjust output data offset for backward compatibility
perf trace beauty: Fix generation of errno id->str table on ALT Linux
perf build-id: Fix caching files with a wrong build ID
tools headers cpufeatures: Sync with the kernel sources
tools headers UAPI: Sync drm/i915_drm.h with the kernel sources
perf inject: Fix missing free in copy_kcore_dir()
Add entry to map ansuelsmth@gmail.com to the unique identity of
Christian Marangi.
Link: https://lkml.kernel.org/r/20220615225012.18782-1-ansuelsmth@gmail.com
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Memory controller drivers - fixes for v5.19
Broken in current cycle:
1. OMAP GPMC: fix Kconfig dependency for OMAP_GPMC, so it will not be visible
for everyone (driver is specific to OMAP).
Broken before:
1. Mediatek SMI: fix missing put_device() in error paths.
2. Exynos DMC: fix OF node leaks in error paths.
* tag 'memory-controller-drv-fixes-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux-mem-ctrl:
memory: samsung: exynos5422-dmc: Fix refcount leak in of_get_dram_timings
memory: mtk-smi: add missing put_device() call in mtk_smi_device_link_common
memory: omap-gpmc: OMAP_GPMC should depend on ARCH_OMAP2PLUS || ARCH_KEYSTONE || ARCH_K3
Link: https://lore.kernel.org/r/20220624081819.33617-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Pull btrfs fixes from David Sterba:
- zoned relocation fixes:
- fix critical section end for extent writeback, this could lead
to out of order write
- prevent writing to previous data relocation block group if space
gets low
- reflink fixes:
- fix race between reflinking and ordered extent completion
- proper error handling when block reserve migration fails
- add missing inode iversion/mtime/ctime updates on each iteration
when replacing extents
- fix deadlock when running fsync/fiemap/commit at the same time
- fix false-positive KCSAN report regarding pid tracking for read locks
and data race
- minor documentation update and link to new site
* tag 'for-5.19-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Documentation: update btrfs list of features and link to readthedocs.io
btrfs: fix deadlock with fsync+fiemap+transaction commit
btrfs: don't set lock_owner when locking extent buffer for reading
btrfs: zoned: fix critical section of relocation inode writeback
btrfs: zoned: prevent allocation from previous data relocation BG
btrfs: do not BUG_ON() on failure to migrate space when replacing extents
btrfs: add missing inode updates on each iteration when replacing extents
btrfs: fix race between reflinking and ordered extent completion
To pick up the changes from:
d5af44dde5461d12 ("x86/sev: Provide support for SNP guest request NAEs")
0afb6b660a6b58cb ("x86/sev: Use SEV-SNP AP creation to start secondary CPUs")
dc3f3d2474b80eae ("x86/mm: Validate memory when changing the C-bit")
cbd3d4f7c4e5a93e ("x86/sev: Check SEV-SNP features support")
That gets these new SVM exit reasons:
+ { SVM_VMGEXIT_PSC, "vmgexit_page_state_change" }, \
+ { SVM_VMGEXIT_GUEST_REQUEST, "vmgexit_guest_request" }, \
+ { SVM_VMGEXIT_EXT_GUEST_REQUEST, "vmgexit_ext_guest_request" }, \
+ { SVM_VMGEXIT_AP_CREATION, "vmgexit_ap_creation" }, \
+ { SVM_VMGEXIT_HV_FEATURES, "vmgexit_hypervisor_feature" }, \
Addressing this perf build warning:
Warning: Kernel ABI header at 'tools/arch/x86/include/uapi/asm/svm.h' differs from latest version at 'arch/x86/include/uapi/asm/svm.h'
diff -u tools/arch/x86/include/uapi/asm/svm.h arch/x86/include/uapi/asm/svm.h
This causes these changes:
CC /tmp/build/perf-urgent/arch/x86/util/kvm-stat.o
LD /tmp/build/perf-urgent/arch/x86/util/perf-in.o
LD /tmp/build/perf-urgent/arch/x86/perf-in.o
LD /tmp/build/perf-urgent/arch/perf-in.o
LD /tmp/build/perf-urgent/perf-in.o
LINK /tmp/build/perf-urgent/perf
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently unpoison_memory(unsigned long pfn) is designed for soft
poison(hwpoison-inject) only. Since 17fae1294ad9d, the KPTE gets cleared
on a x86 platform once hardware memory corrupts.
Unpoisoning a hardware corrupted page puts page back buddy only, the
kernel has a chance to access the page with *NOT PRESENT* KPTE. This
leads BUG during accessing on the corrupted KPTE.
Suggested by David&Naoya, disable unpoison mechanism when a real HW error
happens to avoid BUG like this:
Unpoison: Software-unpoisoned page 0x61234
BUG: unable to handle page fault for address: ffff888061234000
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 2c01067 P4D 2c01067 PUD 107267063 PMD 10382b063 PTE 800fffff9edcb062
Oops: 0002 [#1] PREEMPT SMP NOPTI
CPU: 4 PID: 26551 Comm: stress Kdump: loaded Tainted: G M OE 5.18.0.bm.1-amd64 #7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ...
RIP: 0010:clear_page_erms+0x7/0x10
Code: ...
RSP: 0000:ffffc90001107bc8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000901 RCX: 0000000000001000
RDX: ffffea0001848d00 RSI: ffffea0001848d40 RDI: ffff888061234000
RBP: ffffea0001848d00 R08: 0000000000000901 R09: 0000000000001276
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000140dca R15: 0000000000000001
FS: 00007fd8b2333740(0000) GS:ffff88813fd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff888061234000 CR3: 00000001023d2005 CR4: 0000000000770ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
prep_new_page+0x151/0x170
get_page_from_freelist+0xca0/0xe20
? sysvec_apic_timer_interrupt+0xab/0xc0
? asm_sysvec_apic_timer_interrupt+0x1b/0x20
__alloc_pages+0x17e/0x340
__folio_alloc+0x17/0x40
vma_alloc_folio+0x84/0x280
__handle_mm_fault+0x8d4/0xeb0
handle_mm_fault+0xd5/0x2a0
do_user_addr_fault+0x1d0/0x680
? kvm_read_and_reset_apf_flags+0x3b/0x50
exc_page_fault+0x78/0x170
asm_exc_page_fault+0x27/0x30
Link: https://lkml.kernel.org/r/20220615093209.259374-2-pizhenwei@bytedance.com
Fixes: 847ce401df392 ("HWPOISON: Add unpoisoning support")
Fixes: 17fae1294ad9d ("x86/{mce,mm}: Unmap the entire page if the whole page is affected and poisoned")
Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org> [5.8+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Samsung fixes for v5.19
Both fixes are for issues present before v5.19 merge window:
1. Correct UART clocks on Exynos7885. Although the initial, fixed
DTS commit is from v5.18, the issue will be exposed with a upcoming fix
to Exynos7885 clock driver, so we need to correct the DTS earlier.
2. Fix theoretical OF node leak in Exynos machine code.
* tag 'samsung-fixes-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux:
ARM: exynos: Fix refcount leak in exynos_map_pmu
arm64: dts: exynos: Correct UART clocks on Exynos7885
Link: https://lore.kernel.org/r/20220624080423.31427-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
of_parse_phandle() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not need anymore.
This function doesn't call of_node_put() in some error paths.
To unify the structure, Add put_node label and goto it on errors.
Fixes: 6e7674c3c6df ("memory: Add DMC driver for Exynos5422")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://lore.kernel.org/r/20220602041721.64348-1-linmq006@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Pull dma-mapping fix from Christoph Hellwig:
- pass the correct size to dma_set_encrypted() when freeing memory
(Dexuan Cui)
* tag 'dma-mapping-5.19-2022-06-26' of git://git.infradead.org/users/hch/dma-mapping:
dma-direct: use the correct size for dma_set_encrypted()
The btrfs documentation in kernel is only meant as a starting point, so
update the list of features and add link to btrfs.readthedocs.io page
that is most up-to-date. The wiki is still used but information is
migrated from there.
Signed-off-by: David Sterba <dsterba@suse.com>
README