On 05/20/22 at 08:45am, Palmer Dabbelt wrote:
> On Fri, 08 Apr 2022 03:09:09 PDT (-0700), [email protected] wrote:
> > From: Liao Chang <[email protected]>
> >
> > When CONFIG_KEXEC_FILE is set for riscv platform, the compilation of
> > kernel/kexec_file.c generate build error:
> >
> > kernel/kexec_file.c: In function 'crash_prepare_elf64_headers':
> > ./arch/riscv/include/asm/page.h:110:71: error: request for member 'virt_addr' in something not a structure or union
> > 110 | ((x) >= PAGE_OFFSET && (!IS_ENABLED(CONFIG_64BIT) || (x) < kernel_map.virt_addr))
> > | ^
> > ./arch/riscv/include/asm/page.h:131:2: note: in expansion of macro 'is_linear_mapping'
> > 131 | is_linear_mapping(_x) ? \
> > | ^~~~~~~~~~~~~~~~~
> > ./arch/riscv/include/asm/page.h:140:31: note: in expansion of macro '__va_to_pa_nodebug'
> > 140 | #define __phys_addr_symbol(x) __va_to_pa_nodebug(x)
> > | ^~~~~~~~~~~~~~~~~~
> > ./arch/riscv/include/asm/page.h:143:24: note: in expansion of macro '__phys_addr_symbol'
> > 143 | #define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
> > | ^~~~~~~~~~~~~~~~~~
> > kernel/kexec_file.c:1327:36: note: in expansion of macro '__pa_symbol'
> > 1327 | phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
> >
> > This occurs is because the "kernel_map" referenced in macro
> > is_linear_mapping() is suppose to be the one of struct kernel_mapping
> > defined in arch/riscv/mm/init.c, but the 2nd argument of
> > crash_prepare_elf64_header() has same symbol name, in expansion of macro
> > is_linear_mapping in function crash_prepare_elf64_header(), "kernel_map"
> > actually is the local variable.
> >
> > Signed-off-by: Liao Chang <[email protected]>
> > ---
> > include/linux/kexec.h | 2 +-
> > kernel/kexec_file.c | 4 ++--
> > 2 files changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> > index 58d1b58a971e..ebb1bffbf068 100644
> > --- a/include/linux/kexec.h
> > +++ b/include/linux/kexec.h
> > @@ -227,7 +227,7 @@ struct crash_mem {
> > extern int crash_exclude_mem_range(struct crash_mem *mem,
> > unsigned long long mstart,
> > unsigned long long mend);
> > -extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
> > +extern int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
> > void **addr, unsigned long *sz);
> > #endif /* CONFIG_KEXEC_FILE */
> >
> > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> > index 8347fc158d2b..331a4f0f10f5 100644
> > --- a/kernel/kexec_file.c
> > +++ b/kernel/kexec_file.c
> > @@ -1260,7 +1260,7 @@ int crash_exclude_mem_range(struct crash_mem *mem,
> > return 0;
> > }
> >
> > -int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
> > +int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
> > void **addr, unsigned long *sz)
> > {
> > Elf64_Ehdr *ehdr;
> > @@ -1324,7 +1324,7 @@ int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
> > phdr++;
> >
> > /* Prepare PT_LOAD type program header for kernel text region */
> > - if (kernel_map) {
> > + if (need_kernel_map) {
> > phdr->p_type = PT_LOAD;
> > phdr->p_flags = PF_R|PF_W|PF_X;
> > phdr->p_vaddr = (unsigned long) _text;
>
> IMO this is fine: we could rename all the kernel_map stuff in arch/riscv,
> but this is much more self-contained. It's not been ack'd by anyone else,
> but get_maintainers just suggests the kexec@ list so I'm going to take it
> via the RISC-V tree along with the rest of these.
I ever checked this patch, and thought the renaming of kernel_map in
arch/riscv might be more reasonable, because 'need_kernel_map' is obviously
redundant and looks silly, considering in a generic code. But searching
result of kernel_map under arch/riscv stops me suggesting that.