[PATCH -next V14 4/7] riscv: entry: Convert to generic entry

[Guo Ren]

Thx, I got that:

  LD      vmlinux
riscv64-unknown-linux-gnu-ld: arch/riscv/kernel/traps.o: in function
`do_trap_ecall_u':
/home/guoren/source/kernel/linux/arch/riscv/kernel/traps.c:245:
undefined reference to `handle_page_fault'
make[2]: *** [/home/guoren/source/kernel/linux/scripts/Makefile.vmlinux:34:
vmlinux] Error 1
make[1]: *** [/home/guoren/source/kernel/linux/Makefile:1252: vmlinux] Error 2
make[1]: Leaving directory '/home/guoren/source/kernel/build-nommu'
make: *** [Makefile:242: __sub-make] Error 2

Sorry.

And here is the fixup:

diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index 0b764071de8c..69d619ddbcd5 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c
@@ -268,6 +268,7 @@ asmlinkage __visible __trap_section void
do_trap_ecall_u(struct pt_regs *regs)

 }

+#ifdef CONFIG_MMU
 asmlinkage __visible noinstr void do_page_fault(struct pt_regs *regs)
 {
        irqentry_state_t state = irqentry_enter(regs);
@@ -278,6 +279,7 @@ asmlinkage __visible noinstr void
do_page_fault(struct pt_regs *regs)

        irqentry_exit(regs, state);
 }
+#endif

 asmlinkage __visible noinstr void do_irq(struct pt_regs *regs)
 {

On Fri, Jan 13, 2023 at 5:23 PM Conor Dooley <conor.dooley at microchip.com> wrote:
>
> Hey Guo Ren,
>
> On Thu, Jan 12, 2023 at 04:58:45AM -0500, guoren at kernel.org wrote:
> > From: Guo Ren <guoren at linux.alibaba.com>
> >
> > This patch converts riscv to use the generic entry infrastructure from
> > kernel/entry/*. The generic entry makes maintainers' work easier and
> > codes more elegant. Here are the changes:
> >
> >  - More clear entry.S with handle_exception and ret_from_exception
> >  - Get rid of complex custom signal implementation
> >  - Move syscall procedure from assembly to C, which is much more
> >    readable.
> >  - Connect ret_from_fork & ret_from_kernel_thread to generic entry.
> >  - Wrap with irqentry_enter/exit and syscall_enter/exit_from_user_mode
> >  - Use the standard preemption code instead of custom
> >
> > Suggested-by: Huacai Chen <chenhuacai at kernel.org>
> > Reviewed-by: Björn Töpel <bjorn at rivosinc.com>
> > Tested-by: Yipeng Zou <zouyipeng at huawei.com>
> > Tested-by: Jisheng Zhang <jszhang at kernel.org>
> > Signed-off-by: Guo Ren <guoren at linux.alibaba.com>
> > Signed-off-by: Guo Ren <guoren at kernel.org>
> > Cc: Ben Hutchings <ben at decadent.org.uk>
>
> Unfortunately from this patch onwards, the !MMU build is broken.
> Should be able to reproduce it with nommu_virt_defconfig.
>
> Thanks,
> Conor.
>


-- 
Best Regards
 Guo Ren