tjh.dev
Linux kernel
============
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Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
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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
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Clone this repository
https://tangled.org/tjh.dev/kernel
git@gordian.tjh.dev:tjh.dev/kernel
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Add my personal email address to KASAN reviewers list.
Link: https://lkml.kernel.org/r/c1ce89a7aae0e2d6852249c280b1eb59aeac30c0.1613150186.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use my personal email address.
Link: https://lkml.kernel.org/r/b0ec98dabbc12336c162788f5ccde97045a0d65e.1613150186.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Account for the following files:
- lib/Kconfig.kasan
- lib/test_kasan_module.c
- arch/arm64/include/asm/mte-kasan.h
Link: https://lkml.kernel.org/r/7f9771d97b34d396bfdc4e288ad93486bb865a06.1613150186.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kernel test robot reported the following issue:
CC [M] drivers/soc/litex/litex_soc_ctrl.o
sh4-linux-objcopy: Unable to change endianness of input file(s)
sh4-linux-ld: cannot find drivers/soc/litex/.tmp_gl_litex_soc_ctrl.o: No such file or directory
sh4-linux-objcopy: 'drivers/soc/litex/.tmp_mx_litex_soc_ctrl.o': No such file
The problem is that the format of input file is elf32-shbig-linux, but
sh4-linux-objcopy wants to output a file which format is elf32-sh-linux:
$ sh4-linux-objdump -d drivers/soc/litex/litex_soc_ctrl.o | grep format
drivers/soc/litex/litex_soc_ctrl.o: file format elf32-shbig-linux
Link: https://lkml.kernel.org/r/20210210150435.2171567-1-rong.a.chen@intel.com
Link: https://lore.kernel.org/linux-mm/202101261118.GbbYSlHu-lkp@intel.com
Signed-off-by: Rong Chen <rong.a.chen@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Cc: Rich Felker <dalias@libc.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Recent changes that obsoleted DISCONTIGMEM on m68k switched the MMU
variant to use generic definitions of __pfn_to_phys() and __phys_to_pfn(),
but missed the !MMU variant which caused a build failure:
drivers/media/common/videobuf2/videobuf2-dma-contig.c: In function 'vb2_dc_get_userptr':
drivers/media/common/videobuf2/videobuf2-dma-contig.c:509:5: error: implicit declaration of function '__pfn_to_phys' [-Werror=implicit-function-declaration]
509 | __pfn_to_phys(nums[0]), size, buf->dma_dir, 0);
| ^~~~~~~~~~~~~
cc1: some warnings being treated as errors
Enable __pfn_to_phys() and __phys_to_pfn() on !MMU builds.
Link: https://lkml.kernel.org/r/20210211232202.GS299309@linux.ibm.com
Fixes: 4bfc848e0981 ("m68k/mm: enable use of generic memory_model.h for !DISCONTIGMEM")
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull powerpc fix from Michael Ellerman:
"One fix for a regression seen in io_uring, introduced by our support
for KUAP (Kernel User Access Prevention) with the Hash MMU.
Thanks to Aneesh Kumar K.V, and Zorro Lang"
* tag 'powerpc-5.11-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/kuap: Allow kernel thread to access userspace after kthread_use_mm
Pull gpio fixes from Bartosz Golaszewski:
"This is hopefully the last batch of fixes for this release cycle. We
have a minor fix for a Kconfig regression as well as fixes for older
bugs in gpio-ep93xx:
- don't build gpio-mxs unconditionally with COMPILE_TEST enabled
- fix two problems with interrupt handling in gpio-ep93xx"
* tag 'gpio-fixes-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
gpio: ep93xx: Fix single irqchip with multi gpiochips
gpio: ep93xx: fix BUG_ON port F usage
gpio: mxs: GPIO_MXS should not default to y unconditionally
This fix the bad fault reported by KUAP when io_wqe_worker access userspace.
Bug: Read fault blocked by KUAP!
WARNING: CPU: 1 PID: 101841 at arch/powerpc/mm/fault.c:229 __do_page_fault+0x6b4/0xcd0
NIP [c00000000009e7e4] __do_page_fault+0x6b4/0xcd0
LR [c00000000009e7e0] __do_page_fault+0x6b0/0xcd0
..........
Call Trace:
[c000000016367330] [c00000000009e7e0] __do_page_fault+0x6b0/0xcd0 (unreliable)
[c0000000163673e0] [c00000000009ee3c] do_page_fault+0x3c/0x120
[c000000016367430] [c00000000000c848] handle_page_fault+0x10/0x2c
--- interrupt: 300 at iov_iter_fault_in_readable+0x148/0x6f0
..........
NIP [c0000000008e8228] iov_iter_fault_in_readable+0x148/0x6f0
LR [c0000000008e834c] iov_iter_fault_in_readable+0x26c/0x6f0
interrupt: 300
[c0000000163677e0] [c0000000007154a0] iomap_write_actor+0xc0/0x280
[c000000016367880] [c00000000070fc94] iomap_apply+0x1c4/0x780
[c000000016367990] [c000000000710330] iomap_file_buffered_write+0xa0/0x120
[c0000000163679e0] [c00800000040791c] xfs_file_buffered_aio_write+0x314/0x5e0 [xfs]
[c000000016367a90] [c0000000006d74bc] io_write+0x10c/0x460
[c000000016367bb0] [c0000000006d80e4] io_issue_sqe+0x8d4/0x1200
[c000000016367c70] [c0000000006d8ad0] io_wq_submit_work+0xc0/0x250
[c000000016367cb0] [c0000000006e2578] io_worker_handle_work+0x498/0x800
[c000000016367d40] [c0000000006e2cdc] io_wqe_worker+0x3fc/0x4f0
[c000000016367da0] [c0000000001cb0a4] kthread+0x1c4/0x1d0
[c000000016367e10] [c00000000000dbf0] ret_from_kernel_thread+0x5c/0x6c
The kernel consider thread AMR value for kernel thread to be
AMR_KUAP_BLOCKED. Hence access to userspace is denied. This
of course not correct and we should allow userspace access after
kthread_use_mm(). To be precise, kthread_use_mm() should inherit the
AMR value of the operating address space. But, the AMR value is
thread-specific and we inherit the address space and not thread
access restrictions. Because of this ignore AMR value when accessing
userspace via kernel thread.
current_thread_amr/iamr() are updated, because we use them in the
below stack.
....
[ 530.710838] CPU: 13 PID: 5587 Comm: io_wqe_worker-0 Tainted: G D 5.11.0-rc6+ #3
....
NIP [c0000000000aa0c8] pkey_access_permitted+0x28/0x90
LR [c0000000004b9278] gup_pte_range+0x188/0x420
--- interrupt: 700
[c00000001c4ef3f0] [0000000000000000] 0x0 (unreliable)
[c00000001c4ef490] [c0000000004bd39c] gup_pgd_range+0x3ac/0xa20
[c00000001c4ef5a0] [c0000000004bdd44] internal_get_user_pages_fast+0x334/0x410
[c00000001c4ef620] [c000000000852028] iov_iter_get_pages+0xf8/0x5c0
[c00000001c4ef6a0] [c0000000007da44c] bio_iov_iter_get_pages+0xec/0x700
[c00000001c4ef770] [c0000000006a325c] iomap_dio_bio_actor+0x2ac/0x4f0
[c00000001c4ef810] [c00000000069cd94] iomap_apply+0x2b4/0x740
[c00000001c4ef920] [c0000000006a38b8] __iomap_dio_rw+0x238/0x5c0
[c00000001c4ef9d0] [c0000000006a3c60] iomap_dio_rw+0x20/0x80
[c00000001c4ef9f0] [c008000001927a30] xfs_file_dio_aio_write+0x1f8/0x650 [xfs]
[c00000001c4efa60] [c0080000019284dc] xfs_file_write_iter+0xc4/0x130 [xfs]
[c00000001c4efa90] [c000000000669984] io_write+0x104/0x4b0
[c00000001c4efbb0] [c00000000066cea4] io_issue_sqe+0x3d4/0xf50
[c00000001c4efc60] [c000000000670200] io_wq_submit_work+0xb0/0x2f0
[c00000001c4efcb0] [c000000000674268] io_worker_handle_work+0x248/0x4a0
[c00000001c4efd30] [c0000000006746e8] io_wqe_worker+0x228/0x2a0
[c00000001c4efda0] [c00000000019d994] kthread+0x1b4/0x1c0
Fixes: 48a8ab4eeb82 ("powerpc/book3s64/pkeys: Don't update SPRN_AMR when in kernel mode.")
Reported-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210206025634.521979-1-aneesh.kumar@linux.ibm.com
Pull power management fixes from Rafael Wysocki:
"Address a performance regression related to scale-invariance on x86
that may prevent turbo CPU frequencies from being used in certain
workloads on systems using acpi-cpufreq as the CPU performance scaling
driver and schedutil as the scaling governor"
* tag 'pm-5.11-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: ACPI: Update arch scale-invariance max perf ratio if CPPC is not there
cpufreq: ACPI: Extend frequency tables to cover boost frequencies
Fixes the following warnings which results in interrupts disabled on
port B/F:
gpio gpiochip1: (B): detected irqchip that is shared with multiple gpiochips: please fix the driver.
gpio gpiochip5: (F): detected irqchip that is shared with multiple gpiochips: please fix the driver.
- added separate irqchip for each interrupt capable gpiochip
- provided unique names for each irqchip
Fixes: d2b091961510 ("gpio: ep93xx: Pass irqchip when adding gpiochip")
Cc: <stable@vger.kernel.org>
Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>
Tested-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Commit 0138ba5783ae ("powerpc/64/signal: Balance return predictor
stack in signal trampoline") changed __kernel_sigtramp_rt64() VDSO and
trampoline code, and introduced a regression in the way glibc's
backtrace()[1] detects the signal-handler stack frame. Apart from the
practical implications, __kernel_sigtramp_rt64() was a VDSO function
with the semantics that it is a function you can call from userspace
to end a signal handling. Now this semantics are no longer valid.
I believe the aforementioned change affects all releases since 5.9.
This patch tries to fix both the semantics and practical aspect of
__kernel_sigtramp_rt64() returning it to the previous code, whilst
keeping the intended behaviour of 0138ba5783ae by adding a new symbol
to serve as the jump target from the kernel to the trampoline. Now the
trampoline has two parts, a new entry point and the old return point.
[1] https://lists.ozlabs.org/pipermail/linuxppc-dev/2021-January/223194.html
Fixes: 0138ba5783ae ("powerpc/64/signal: Balance return predictor stack in signal trampoline")
Cc: stable@vger.kernel.org # v5.9+
Signed-off-by: Raoni Fassina Firmino <raoni@linux.ibm.com>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Minor tweaks to change log formatting, add stable tag]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210201200505.iz46ubcizipnkcxe@work-tp
Pull ACPI fix from Rafael Wysocki:
"Revert a problematic ACPICA commit that changed the code to attempt to
update memory regions which may be read-only on some systems (Ard
Biesheuvel)"
* tag 'acpi-5.11-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
Revert "ACPICA: Interpreter: fix memory leak by using existing buffer"
If the maximum performance level taken for computing the
arch_max_freq_ratio value used in the x86 scale-invariance code is
higher than the one corresponding to the cpuinfo.max_freq value
coming from the acpi_cpufreq driver, the scale-invariant utilization
falls below 100% even if the CPU runs at cpuinfo.max_freq or slightly
faster, which causes the schedutil governor to select a frequency
below cpuinfo.max_freq. That frequency corresponds to a frequency
table entry below the maximum performance level necessary to get to
the "boost" range of CPU frequencies which prevents "boost"
frequencies from being used in some workloads.
While this issue is related to scale-invariance, it may be amplified
by commit db865272d9c4 ("cpufreq: Avoid configuring old governors as
default with intel_pstate") from the 5.10 development cycle which
made it extremely easy to default to schedutil even if the preferred
driver is acpi_cpufreq as long as intel_pstate is built too, because
the mere presence of the latter effectively removes the ondemand
governor from the defaults. Distro kernels are likely to include
both intel_pstate and acpi_cpufreq on x86, so their users who cannot
use intel_pstate or choose to use acpi_cpufreq may easily be
affectecd by this issue.
If CPPC is available, it can be used to address this issue by
extending the frequency tables created by acpi_cpufreq to cover the
entire available frequency range (including "boost" frequencies) for
each CPU, but if CPPC is not there, acpi_cpufreq has no idea what
the maximum "boost" frequency is and the frequency tables created by
it cannot be extended in a meaningful way, so in that case make it
ask the arch scale-invariance code to to use the "nominal" performance
level for CPU utilization scaling in order to avoid the issue at hand.
Fixes: db865272d9c4 ("cpufreq: Avoid configuring old governors as default with intel_pstate")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Two index spaces and ep93xx_gpio_port are confusing.
Instead add a separate struct to store necessary data and remove
ep93xx_gpio_port.
- add struct to store IRQ related data for each IRQ capable chip
- replace offset array with defined offsets
- add IRQ registers offset for each IRQ capable chip into
ep93xx_gpio_banks
------------[ cut here ]------------
kernel BUG at drivers/gpio/gpio-ep93xx.c:64!
---[ end trace 3f6544e133e9f5ae ]---
Fixes: fd935fc421e74 ("gpio: ep93xx: Do not pingpong irq numbers")
Cc: <stable@vger.kernel.org>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Tested-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
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