2022-03-28 01:30:45

by kernel test robot

[permalink] [raw]
Subject: arch/riscv/mm/init.c:782:83: warning: suggest braces around empty body in an 'if' statement

Hi Qinglin,

FYI, the error/warning still remains.

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: f022814633e1c600507b3a99691b4d624c2813f0
commit: 677b9eb8810edc6c616a699018a83e24ed0cccab riscv: mm: Prepare pt_ops helper functions for sv57
date: 6 weeks ago
config: riscv-rv32_defconfig (https://download.01.org/0day-ci/archive/20220328/[email protected]/config)
compiler: riscv32-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=677b9eb8810edc6c616a699018a83e24ed0cccab
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout 677b9eb8810edc6c616a699018a83e24ed0cccab
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=riscv SHELL=/bin/bash arch/riscv/mm/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>

All warnings (new ones prefixed by >>):

arch/riscv/mm/init.c: In function 'create_fdt_early_page_table':
>> arch/riscv/mm/init.c:782:83: warning: suggest braces around empty body in an 'if' statement [-Wempty-body]
782 | (uintptr_t)early_dtb_pud, P4D_SIZE, PAGE_TABLE);
| ^
arch/riscv/mm/init.c:786:83: warning: suggest braces around empty body in an 'if' statement [-Wempty-body]
786 | (uintptr_t)early_dtb_pmd, PUD_SIZE, PAGE_TABLE);
| ^
arch/riscv/mm/init.c: At top level:
arch/riscv/mm/init.c:813:13: warning: no previous prototype for 'pt_ops_set_early' [-Wmissing-prototypes]
813 | void __init pt_ops_set_early(void)
| ^~~~~~~~~~~~~~~~
arch/riscv/mm/init.c:835:13: warning: no previous prototype for 'pt_ops_set_fixmap' [-Wmissing-prototypes]
835 | void __init pt_ops_set_fixmap(void)
| ^~~~~~~~~~~~~~~~~
arch/riscv/mm/init.c:853:13: warning: no previous prototype for 'pt_ops_set_late' [-Wmissing-prototypes]
853 | void __init pt_ops_set_late(void)
| ^~~~~~~~~~~~~~~


vim +/if +782 arch/riscv/mm/init.c

764
765 /*
766 * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel,
767 * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR
768 * entry.
769 */
770 static void __init create_fdt_early_page_table(pgd_t *pgdir, uintptr_t dtb_pa)
771 {
772 #ifndef CONFIG_BUILTIN_DTB
773 uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1);
774
775 create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
776 IS_ENABLED(CONFIG_64BIT) ? early_dtb_pgd_next : pa,
777 PGDIR_SIZE,
778 IS_ENABLED(CONFIG_64BIT) ? PAGE_TABLE : PAGE_KERNEL);
779
780 if (pgtable_l5_enabled)
781 create_p4d_mapping(early_dtb_p4d, DTB_EARLY_BASE_VA,
> 782 (uintptr_t)early_dtb_pud, P4D_SIZE, PAGE_TABLE);
783
784 if (pgtable_l4_enabled)
785 create_pud_mapping(early_dtb_pud, DTB_EARLY_BASE_VA,
786 (uintptr_t)early_dtb_pmd, PUD_SIZE, PAGE_TABLE);
787
788 if (IS_ENABLED(CONFIG_64BIT)) {
789 create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA,
790 pa, PMD_SIZE, PAGE_KERNEL);
791 create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA + PMD_SIZE,
792 pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
793 }
794
795 dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PMD_SIZE - 1));
796 #else
797 /*
798 * For 64-bit kernel, __va can't be used since it would return a linear
799 * mapping address whereas dtb_early_va will be used before
800 * setup_vm_final installs the linear mapping. For 32-bit kernel, as the
801 * kernel is mapped in the linear mapping, that makes no difference.
802 */
803 dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa));
804 #endif
805
806 dtb_early_pa = dtb_pa;
807 }
808

--
0-DAY CI Kernel Test Service
https://01.org/lkp


2022-04-21 07:18:24

by Palmer Dabbelt

[permalink] [raw]
Subject: Re: arch/riscv/mm/init.c:782:83: warning: suggest braces around empty body in an 'if' statement

On Sun, 27 Mar 2022 09:05:03 PDT (-0700), [email protected] wrote:
> Hi Qinglin,
>
> FYI, the error/warning still remains.

Thanks. I'm not sure if I missed a patch for this, I can't find
anything that looks relevant in my inbox. I just sent one of my own to
fix the issue, but if there's one I missed then happy to take that
instead.

> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: f022814633e1c600507b3a99691b4d624c2813f0
> commit: 677b9eb8810edc6c616a699018a83e24ed0cccab riscv: mm: Prepare pt_ops helper functions for sv57
> date: 6 weeks ago
> config: riscv-rv32_defconfig (https://download.01.org/0day-ci/archive/20220328/[email protected]/config)
> compiler: riscv32-linux-gcc (GCC) 11.2.0
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=677b9eb8810edc6c616a699018a83e24ed0cccab
> git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> git fetch --no-tags linus master
> git checkout 677b9eb8810edc6c616a699018a83e24ed0cccab
> # save the config file to linux build tree
> mkdir build_dir
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=riscv SHELL=/bin/bash arch/riscv/mm/
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <[email protected]>
>
> All warnings (new ones prefixed by >>):
>
> arch/riscv/mm/init.c: In function 'create_fdt_early_page_table':
>>> arch/riscv/mm/init.c:782:83: warning: suggest braces around empty body in an 'if' statement [-Wempty-body]
> 782 | (uintptr_t)early_dtb_pud, P4D_SIZE, PAGE_TABLE);
> | ^
> arch/riscv/mm/init.c:786:83: warning: suggest braces around empty body in an 'if' statement [-Wempty-body]
> 786 | (uintptr_t)early_dtb_pmd, PUD_SIZE, PAGE_TABLE);
> | ^
> arch/riscv/mm/init.c: At top level:
> arch/riscv/mm/init.c:813:13: warning: no previous prototype for 'pt_ops_set_early' [-Wmissing-prototypes]
> 813 | void __init pt_ops_set_early(void)
> | ^~~~~~~~~~~~~~~~
> arch/riscv/mm/init.c:835:13: warning: no previous prototype for 'pt_ops_set_fixmap' [-Wmissing-prototypes]
> 835 | void __init pt_ops_set_fixmap(void)
> | ^~~~~~~~~~~~~~~~~
> arch/riscv/mm/init.c:853:13: warning: no previous prototype for 'pt_ops_set_late' [-Wmissing-prototypes]
> 853 | void __init pt_ops_set_late(void)
> | ^~~~~~~~~~~~~~~
>
>
> vim +/if +782 arch/riscv/mm/init.c
>
> 764
> 765 /*
> 766 * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel,
> 767 * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR
> 768 * entry.
> 769 */
> 770 static void __init create_fdt_early_page_table(pgd_t *pgdir, uintptr_t dtb_pa)
> 771 {
> 772 #ifndef CONFIG_BUILTIN_DTB
> 773 uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1);
> 774
> 775 create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
> 776 IS_ENABLED(CONFIG_64BIT) ? early_dtb_pgd_next : pa,
> 777 PGDIR_SIZE,
> 778 IS_ENABLED(CONFIG_64BIT) ? PAGE_TABLE : PAGE_KERNEL);
> 779
> 780 if (pgtable_l5_enabled)
> 781 create_p4d_mapping(early_dtb_p4d, DTB_EARLY_BASE_VA,
> > 782 (uintptr_t)early_dtb_pud, P4D_SIZE, PAGE_TABLE);
> 783
> 784 if (pgtable_l4_enabled)
> 785 create_pud_mapping(early_dtb_pud, DTB_EARLY_BASE_VA,
> 786 (uintptr_t)early_dtb_pmd, PUD_SIZE, PAGE_TABLE);
> 787
> 788 if (IS_ENABLED(CONFIG_64BIT)) {
> 789 create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA,
> 790 pa, PMD_SIZE, PAGE_KERNEL);
> 791 create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA + PMD_SIZE,
> 792 pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
> 793 }
> 794
> 795 dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PMD_SIZE - 1));
> 796 #else
> 797 /*
> 798 * For 64-bit kernel, __va can't be used since it would return a linear
> 799 * mapping address whereas dtb_early_va will be used before
> 800 * setup_vm_final installs the linear mapping. For 32-bit kernel, as the
> 801 * kernel is mapped in the linear mapping, that makes no difference.
> 802 */
> 803 dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa));
> 804 #endif
> 805
> 806 dtb_early_pa = dtb_pa;
> 807 }
> 808