Re: [PATCH V3 0/7] riscv: Add GENERIC_ENTRY, irq stack support

Guo Ren
2022-09-07T00:54:51Z

On Wed, Sep 7, 2022 at 1:42 AM <Conor.Dooley@microchip.com> wrote:
>
> On 06/09/2022 04:54, guoren@kernel.org wrote:
> > From: Guo Ren <guoren@linux.alibaba.com>
> >
> > The patches convert riscv to use the generic entry infrastructure from
> > kernel/entry/*. Add independent irq stacks (IRQ_STACKS) for percpu to
> > prevent kernel stack overflows. Add the HAVE_SOFTIRQ_ON_OWN_STACK
> > feature for the IRQ_STACKS config. You can try it directly with [1].
>
> Hey Guo Ren,
> I applied this patchset to v6.0-rc4 & ran into a build error:
> /stuff/linux/arch/riscv/kernel/entry.S:347:9: error: operand must be a bare symbol name
> la a3, ((1 << (12)) << (2 + 0))
Yes, please try:
- la a3, IRQ_STACK_SIZE
+ li a3, IRQ_STACK_SIZE

la is for the symbol, not immediate. But why does my toolchain not
report the error?

➜ linux git:(generic_entry_v3) make ARCH=riscv
CROSS_COMPILE=riscv64-unknown-linux-gnu- EXTRA_CFLAGS+=-g
O=../build-riscv/ -kj62 all -kj
➜ linux git:(generic_entry_v3) riscv64-unknown-linux-gnu-gcc -v
Using built-in specs.
COLLECT_GCC=riscv64-unknown-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/opt/riscv/libexec/gcc/riscv64-unknown-linux-gnu/11.1.0/lto-wrapper
Target: riscv64-unknown-linux-gnu
Configured with:
/home/guoren/source/riscv-gnu-toolchain/riscv-gcc/configure
--target=riscv64-unknown-linux-gnu --prefix=/opt/riscv
--with-sysroot=/opt/riscv/sysroot --with-pkgversion=g5964b5cd7272
--with-system-zlib --enable-shared --enable-tls
--enable-languages=c,c++,fortran --disable-libmudflap --disable-libssp
--disable-libquadmath --disable-libsanitizer --disable-nls
--disable-bootstrap --src=.././riscv-gcc --enable-multilib
--with-abi=lp64d --with-arch=rv64imafdc --with-tune=rocket
--with-isa-spec=2.2 'CFLAGS_FOR_TARGET=-O2 -mcmodel=medlow'
'CXXFLAGS_FOR_TARGET=-O2 -mcmodel=medlow'
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 11.1.0 (g5964b5cd7272)

> ^
> CC arch/riscv/kernel/process.o
> make[5]: *** [/stuff/linux/scripts/Makefile.build:322: arch/riscv/kernel/entry.o] Error 1
> make[5]: *** Waiting for unfinished jobs....
>
> Thanks,
> Conor.
> >
> > [1] https://github.com/guoren83/linux/tree/generic_entry_v3
> >
> > V3:
> > - Fixup CONFIG_COMPAT=n compile error
> > - Add THREAD_SIZE_ORDER config
> > - Optimize elf_kexec.c warning fixup
> > - Add static to irq_stack_ptr definition
> >
> > V2:
> > Link: https://lore.kernel.org/linux-riscv/20220904072637.8619-1-guoren@kernel.org/
> > - Fixup compile error by include "riscv: ptrace: Remove duplicate
> > operation"
> > - Fixup compile warning
> > Reported-by: kernel test robot <lkp@intel.com>
> > - Add test repo link in cover letter
> >
> > V1:
> > Link: https://lore.kernel.org/linux-riscv/20220903163808.1954131-1-guoren@kernel.org/
> >
> > Guo Ren (7):
> > riscv: elf_kexec: Fixup compile warning
> > riscv: compat_syscall_table: Fixup compile warning
> > riscv: ptrace: Remove duplicate operation
> > riscv: convert to generic entry
> > riscv: Support HAVE_IRQ_EXIT_ON_IRQ_STACK
> > riscv: Support HAVE_SOFTIRQ_ON_OWN_STACK
> > riscv: Add config of thread stack size
> >
> > arch/riscv/Kconfig | 19 ++
> > arch/riscv/include/asm/csr.h | 1 -
> > arch/riscv/include/asm/entry-common.h | 8 +
> > arch/riscv/include/asm/irq.h | 3 +
> > arch/riscv/include/asm/ptrace.h | 10 +-
> > arch/riscv/include/asm/stacktrace.h | 5 +
> > arch/riscv/include/asm/syscall.h | 6 +
> > arch/riscv/include/asm/thread_info.h | 19 +-
> > arch/riscv/include/asm/vmap_stack.h | 28 +++
> > arch/riscv/kernel/Makefile | 1 +
> > arch/riscv/kernel/elf_kexec.c | 2 +-
> > arch/riscv/kernel/entry.S | 255 +++++---------------------
> > arch/riscv/kernel/irq.c | 75 ++++++++
> > arch/riscv/kernel/ptrace.c | 41 -----
> > arch/riscv/kernel/signal.c | 21 +--
> > arch/riscv/kernel/sys_riscv.c | 27 +++
> > arch/riscv/kernel/traps.c | 11 ++
> > arch/riscv/mm/fault.c | 12 +-
> > 18 files changed, 259 insertions(+), 285 deletions(-)
> > create mode 100644 arch/riscv/include/asm/entry-common.h
> > create mode 100644 arch/riscv/include/asm/vmap_stack.h
> >

--
Best Regards
Guo Ren