tjh.dev
Linux kernel
============
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``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
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When CONFIG_KEXEC_FILE=y but CONFIG_KEXEC is not set:
kernel/kexec_core.o: In function `kimage_free':
kexec_core.c:(.text+0xa0c): undefined reference to `machine_kexec_cleanup'
kernel/kexec_core.o: In function `.L0 ':
kexec_core.c:(.text+0xde8): undefined reference to `machine_crash_shutdown'
kexec_core.c:(.text+0xdf4): undefined reference to `machine_kexec'
kernel/kexec_core.o: In function `.L231':
kexec_core.c:(.text+0xe1c): undefined reference to `riscv_crash_save_regs'
kernel/kexec_core.o: In function `.L0 ':
kexec_core.c:(.text+0x119e): undefined reference to `machine_shutdown'
kernel/kexec_core.o: In function `.L312':
kexec_core.c:(.text+0x11b2): undefined reference to `machine_kexec'
kernel/kexec_file.o: In function `.L0 ':
kexec_file.c:(.text+0xb84): undefined reference to `machine_kexec_prepare'
kernel/kexec_file.o: In function `.L177':
kexec_file.c:(.text+0xc5a): undefined reference to `machine_kexec_prepare'
Makefile:1160: recipe for target 'vmlinux' failed
make: *** [vmlinux] Error 1
These symbols should depend on CONFIG_KEXEC_CORE rather than CONFIG_KEXEC
when kexec_file has been implemented on RISC-V, like the other archs have
done.
Signed-off-by: Li Zhengyu <lizhengyu3@huawei.com>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20220601070204.26882-1-lizhengyu3@huawei.com
Fixes: 6261586e0c91 ("RISC-V: Add kexec_file support")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
When CONFIG_MODULES is not set/enabled:
../arch/riscv/kernel/elf_kexec.c:353:9: error: unknown type name 'Elf_Rela'; did you mean 'Elf64_Rela'?
353 | Elf_Rela *relas;
| ^~~~~~~~
| Elf64_Rela
Replace Elf_Rela by Elf64_Rela to avoid relying on CONFIG_MODULES.
Signed-off-by: Li Zhengyu <lizhengyu3@huawei.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20220601063924.13037-1-lizhengyu3@huawei.com
Fixes: 838b3e28488f ("RISC-V: Load purgatory in kexec_file")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Microchip RISC-V devicetree fixes for 5.19-rc6
A single fix for mpfs.dtsi:
- The l2 cache controller was never hooked up in the dt, so userspace
is presented with the wrong topology information, so it has been
hooked up.
* tag 'dt-fixes-for-palmer-5.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/conor/linux.git:
riscv: dts: microchip: hook up the mpfs' l2cache
The SiFive errata code contains code checking applicable erratas
vs. actually applied erratas to suggest missing erratas to the
user when their Kconfig options are not enabled.
In the main kernel image one can be quite sure that all available
erratas appear at least once, so that check will succeed.
On the other hand modules can very well not use any errata-relevant
code, so the newly added module-alternative support may also patch
the module code, but not touch SiFive-specific erratas at all.
So to restore the original behaviour don't warn when patching
modules. This will keep the warning if necessary for the main kernel
image but prevent spurious warnings for modules.
Of course having such a vendor-specific warning may not be needed at
all, as CONFIG_ERRATA_SIFIVE is selected by CONFIG_SOC_SIFIVE and the
individual erratas are default-y so disabling them requires
deliberate action anyway. But for now just restore the old behaviour.
Fixes: a8e910168bba ("riscv: implement module alternatives")
Reported-by: Ron Economos <re@w6rz.net>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Ron Economos <re@w6rz.net>
Link: https://lore.kernel.org/r/20220608120849.1695191-1-heiko@sntech.de
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The initial PolarFire SoC devicetree must have been forked off from
the fu540 one prior to the addition of l2cache controller support being
added there. When the controller node was added to mpfs.dtsi, it was
not hooked up to the CPUs & thus sysfs reports an incorrect cache
configuration. Hook it up.
Fixes: 0fa6107eca41 ("RISC-V: Initial DTS for Microchip ICICLE board")
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
After commit a35707c3d850 ("riscv: add memory-type errata for T-Head"),
builds with LLVM's integrated assembler fail like:
In file included from arch/riscv/kernel/asm-offsets.c:10:
In file included from ./include/linux/mm.h:29:
In file included from ./include/linux/pgtable.h:6:
In file included from ./arch/riscv/include/asm/pgtable.h:114:
./arch/riscv/include/asm/pgtable-64.h:210:2: error: invalid input constraint '0' in asm
ALT_THEAD_PMA(prot_val);
^
./arch/riscv/include/asm/errata_list.h:88:4: note: expanded from macro 'ALT_THEAD_PMA'
: "0"(_val), \
^
This was reported upstream to LLVM where Jessica pointed out a couple of
issues with the existing implementation of ALT_THEAD_PMA:
* t3 is modified but not listed in the clobbers list.
* "+r"(_val) marks _val as both an input and output of the asm but then
"0"(_val) marks _val as an input matching constraint, which does not
make much sense in this situation, as %1 is not actually used in the
asm and matching constraints are designed to be used for different
inputs that need to use the same register.
Drop the matching contraint and shift all the operands by one, as %1 is
unused, and mark t3 as clobbered. This resolves the build error and goes
not cause any problems with GNU as.
Fixes: a35707c3d850 ("riscv: add memory-type errata for T-Head")
Link: https://github.com/ClangBuiltLinux/linux/issues/1641
Link: https://github.com/llvm/llvm-project/issues/55514
Link: https://gcc.gnu.org/onlinedocs/gcc/Simple-Constraints.html
Suggested-by: Jessica Clarke <jrtc27@jrtc27.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20220518184529.454008-1-nathan@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
PolarFire SoC /does/ have a SiFive pdma, despite what I suggested as a
conflict resolution to Zong. Somehow the entry fell through the cracks
between versions of my dt patches, so re-add it with Zong's updated
compatible & dma-channels property.
Fixes: c5094f371008 ("riscv: dts: microchip: refactor icicle kit device tree")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Some additionals comments and notes from autobuilders received after the
series got applied, warranted some changes.
* commit '924cbb8cbe3460ea192e6243017ceb0ceb255b1b':
riscv: Improve description for RISCV_ISA_SVPBMT Kconfig symbol
riscv: drop cpufeature_apply_feature tracking variable
riscv: fix dependency for t-head errata
Microchip RISC-V devicetree fixes for 5.19-rc3
A single fix for mpfs.dtsi:
- The sifive pdma entry fell through the cracks between versions of my
dt patches & I gave Zong the wrong conflict resolution, so it is
added back.
* tag 'dt-fixes-for-palmer-5.19-rc3' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/conor/linux:
riscv: dts: microchip: re-add pdma to mpfs device tree
This improves the symbol's description to make it easier for
people to understand what it is about.
Suggested-by: Christoph Hellwig <hch@lst.de>
Suggested-by: Philipp Tomsich <philipp.tomsich@vrull.eu>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Guo Ren <guoren@kernel.org>
Link: https://lore.kernel.org/r/20220526205646.258337-3-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Pull file descriptor fix from Al Viro:
"Fix for breakage in #work.fd this window"
* tag 'pull-work.fd-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fix the breakage in close_fd_get_file() calling conventions change
The variable was tracking which feature patches got applied
but that information was never actually used - and thus resulted
in a warning as well.
Drop the variable.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Guo Ren <guoren@kernel.org>
Link: https://lore.kernel.org/r/20220526205646.258337-2-heiko@sntech.de
Fixes: ff689fd21cb1 ("riscv: add RISC-V Svpbmt extension support")
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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