Re: [PATCH v3 2/6] riscv: Rework kasan population functions

From: Alexandre Ghiti <alexghiti@rivosinc.com>
To: kernel test robot <lkp@intel.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	 Albert Ou <aou@eecs.berkeley.edu>,
	Andrey Ryabinin <ryabinin.a.a@gmail.com>,
	 Alexander Potapenko <glider@google.com>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	 Dmitry Vyukov <dvyukov@google.com>,
	Vincenzo Frascino <vincenzo.frascino@arm.com>,
	 Ard Biesheuvel <ardb@kernel.org>,
	Conor Dooley <conor@kernel.org>,
	linux-riscv@lists.infradead.org,  linux-kernel@vger.kernel.org,
	kasan-dev@googlegroups.com,  linux-efi@vger.kernel.org,
	oe-kbuild-all@lists.linux.dev
Subject: Re: [PATCH v3 2/6] riscv: Rework kasan population functions
Date: Thu, 2 Feb 2023 15:00:02 +0100	[thread overview]
Message-ID: <CAHVXubht443DmB6qZMJ=Hyxz=xi65Dkd=PuN_2i=uf783z0B=Q@mail.gmail.com> (raw)
In-Reply-To: <202302010819.RAsjyv6V-lkp@intel.com>

On Wed, Feb 1, 2023 at 1:16 AM kernel test robot <lkp@intel.com> wrote:
>
> Hi Alexandre,
>
> Thank you for the patch! Perhaps something to improve:
>
> [auto build test WARNING on linus/master]
> [also build test WARNING on v6.2-rc6 next-20230131]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
>
> url:    https://github.com/intel-lab-lkp/linux/commits/Alexandre-Ghiti/riscv-Split-early-and-final-KASAN-population-functions/20230125-163113
> patch link:    https://lore.kernel.org/r/20230125082333.1577572-3-alexghiti%40rivosinc.com
> patch subject: [PATCH v3 2/6] riscv: Rework kasan population functions
> config: riscv-randconfig-r006-20230201 (https://download.01.org/0day-ci/archive/20230201/202302010819.RAsjyv6V-lkp@intel.com/config)
> compiler: riscv64-linux-gcc (GCC) 12.1.0
> 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://github.com/intel-lab-lkp/linux/commit/c18726e8d14edbd59ec19854b4eb06d83fff716f
>         git remote add linux-review https://github.com/intel-lab-lkp/linux
>         git fetch --no-tags linux-review Alexandre-Ghiti/riscv-Split-early-and-final-KASAN-population-functions/20230125-163113
>         git checkout c18726e8d14edbd59ec19854b4eb06d83fff716f
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=riscv olddefconfig
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash arch/riscv/mm/
>
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
>
> All warnings (new ones prefixed by >>):
>
> >> arch/riscv/mm/kasan_init.c:442:6: warning: no previous prototype for 'create_tmp_mapping' [-Wmissing-prototypes]
>      442 | void create_tmp_mapping(void)
>          |      ^~~~~~~~~~~~~~~~~~
>
>
> vim +/create_tmp_mapping +442 arch/riscv/mm/kasan_init.c
>
>    441
>  > 442  void create_tmp_mapping(void)
>    443  {
>    444          void *ptr;
>    445          p4d_t *base_p4d;
>    446
>    447          /*
>    448           * We need to clean the early mapping: this is hard to achieve "in-place",
>    449           * so install a temporary mapping like arm64 and x86 do.
>    450           */
>    451          memcpy(tmp_pg_dir, swapper_pg_dir, sizeof(pgd_t) * PTRS_PER_PGD);
>    452
>    453          /* Copy the last p4d since it is shared with the kernel mapping. */
>    454          if (pgtable_l5_enabled) {
>    455                  ptr = (p4d_t *)pgd_page_vaddr(*pgd_offset_k(KASAN_SHADOW_END));
>    456                  memcpy(tmp_p4d, ptr, sizeof(p4d_t) * PTRS_PER_P4D);
>    457                  set_pgd(&tmp_pg_dir[pgd_index(KASAN_SHADOW_END)],
>    458                          pfn_pgd(PFN_DOWN(__pa(tmp_p4d)), PAGE_TABLE));
>    459                  base_p4d = tmp_p4d;
>    460          } else {
>    461                  base_p4d = (p4d_t *)tmp_pg_dir;
>    462          }
>    463
>    464          /* Copy the last pud since it is shared with the kernel mapping. */
>    465          if (pgtable_l4_enabled) {
>    466                  ptr = (pud_t *)p4d_page_vaddr(*(base_p4d + p4d_index(KASAN_SHADOW_END)));
>    467                  memcpy(tmp_pud, ptr, sizeof(pud_t) * PTRS_PER_PUD);
>    468                  set_p4d(&base_p4d[p4d_index(KASAN_SHADOW_END)],
>    469                          pfn_p4d(PFN_DOWN(__pa(tmp_pud)), PAGE_TABLE));
>    470          }
>    471  }
>    472

Ok, I have to declare this function static to quiet this warning,
there will be a v4 soon then.

>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests