[PW_SID:1053085] arch, mm: consolidate empty_zero_page by linux-riscv-bot · Pull Request #1472 · linux-riscv/linux

linux-riscv-bot · 2026-02-12T21:05:19Z

PR for series 1053085 applied to workflow

Name: arch, mm: consolidate empty_zero_page
URL: https://patchwork.kernel.org/project/linux-riscv/list/?series=1053085
Version: 3

nommu architectures have empty_zero_page and define ZERO_PAGE() and although they don't really use it to populate page tables, there is no reason to hardwire !MMU implementation of is_zero_pfn() and my_zero_pfn() to 0. Drop #ifdef CONFIG_MMU around implementations of is_zero_pfn() and my_zero_pfn() and remove !MMU version. While on it, make zero_pfn __ro_after_init. Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Linux RISC-V bot <linux.riscv.bot@gmail.com>

my_zero_pfn() is a silly name. Rename zero_pfn variable to zero_page_pfn and my_zero_pfn() function to zero_pfn(). While on it, move extern declarations of zero_page_pfn outside the functions that use it and add a comment about what ZERO_PAGE is. Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Linux RISC-V bot <linux.riscv.bot@gmail.com>

Reduce 22 declarations of empty_zero_page to 3 and 23 declarations of ZERO_PAGE() to 4. Every architecture defines empty_zero_page that way or another, but for the most of them it is always a page aligned page in BSS and most definitions of ZERO_PAGE do virt_to_page(empty_zero_page). Move Linus vetted x86 definition of empty_zero_page and ZERO_PAGE() to the core MM and drop these definitions in architectures that do not implement colored zero page (MIPS and s390). ZERO_PAGE() remains a macro because turning it to a wrapper for a static inline causes severe pain in header dependencies. For the most part the change is mechanical, with these being noteworthy: * alpha: aliased empty_zero_page with ZERO_PGE that was also used for boot parameters. Switching to a generic empty_zero_page removes the aliasing and keeps ZERO_PGE for boot parameters only * arm64: uses __pa_symbol() in ZERO_PAGE() so that definition of ZERO_PAGE() is kept intact. * m68k/parisc/um: allocated empty_zero_page from memblock, although they do not support zero page coloring and having it in BSS will work fine. * sparc64 can have empty_zero_page in BSS rather allocate it, but it can't use virt_to_page() for BSS. Keep it's definition of ZERO_PAGE() but instead of allocating it, make mem_map_zero point to empty_zero_page. * sh: used empty_zero_page for boot parameters at the very early boot. Rename the parameters page to boot_params_page and let sh use the generic empty_zero_page. * hexagon: had an amusing comment about empty_zero_page /* A handy thing to have if one has the RAM. Declared in head.S */ that unfortunately had to go :) Acked-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Helge Deller <deller@gmx.de> # parisc Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Magnus Lindholm <linmag7@gmail.com> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Acked-by: Andreas Larsson <andreas@gaisler.com> #sparc Acked-by: David Hildenbrand (Arm) <david@kernel.org> Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Linux RISC-V bot <linux.riscv.bot@gmail.com>

For most architectures every invocation of ZERO_PAGE() does virt_to_page(empty_zero_page). But empty_zero_page is in BSS and it is enough to get its struct page once at initialization time and then use it whenever a zero page should be accessed. Add yet another __zero_page variable that will be initialized as virt_to_page(empty_zero_page) for most architectures in a weak arch_setup_zero_pages() function. For architectures that use colored zero pages (MIPS and s390) rename their setup_zero_pages() to arch_setup_zero_pages() and make it global rather than static. For architectures that cannot use virt_to_page() for BSS (arm64 and sparc64) add override of arch_setup_zero_pages(). Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Linux RISC-V bot <linux.riscv.bot@gmail.com>

linux-riscv-bot · 2026-02-12T21:11:02Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
build-rv32-defconfig
Desc: Builds riscv32 defconfig
Duration: 121.05 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T21:47:53Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
build-rv64-clang-allmodconfig
Desc: Builds riscv64 allmodconfig with Clang, and checks for errors and added warnings
Duration: 2209.48 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T22:37:00Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
build-rv64-gcc-allmodconfig
Desc: Builds riscv64 allmodconfig with GCC, and checks for errors and added warnings
Duration: 2945.77 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T22:37:30Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
build-rv64-nommu-k210-defconfig
Desc: Builds riscv64 defconfig with NOMMU for K210
Duration: 27.18 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T22:37:59Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
build-rv64-nommu-k210-virt
Desc: Builds riscv64 defconfig with NOMMU for the virt platform
Duration: 28.35 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T22:38:02Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
checkpatch
Desc: Runs checkpatch.pl on the patch
Duration: 1.40 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T22:39:28Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
dtb-warn-rv64
Desc: Checks for Device Tree warnings/errors
Duration: 83.35 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T22:39:30Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
header-inline
Desc: Detects static functions without inline keyword in header files
Duration: 0.23 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T22:39:33Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
kdoc
Desc: Detects for kdoc errors
Duration: 1.00 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T22:39:35Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
module-param
Desc: Detect module_param changes
Duration: 0.28 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T22:39:37Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
verify-fixes
Desc: Verifies that the Fixes: tags exist
Duration: 0.21 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T22:39:38Z

Patch 1: "[v3,1/4] mm: don't special case !MMU for is_zero_pfn() and my_zero_pfn()"
verify-signedoff
Desc: Verifies that Signed-off-by: tags are correct
Duration: 0.29 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T22:41:56Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
build-rv32-defconfig
Desc: Builds riscv32 defconfig
Duration: 120.67 seconds
Result: PASS

linux-riscv-bot · 2026-02-12T23:18:35Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
build-rv64-clang-allmodconfig
Desc: Builds riscv64 allmodconfig with Clang, and checks for errors and added warnings
Duration: 2197.22 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T00:07:43Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
build-rv64-gcc-allmodconfig
Desc: Builds riscv64 allmodconfig with GCC, and checks for errors and added warnings
Duration: 2946.01 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T00:08:12Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
build-rv64-nommu-k210-defconfig
Desc: Builds riscv64 defconfig with NOMMU for K210
Duration: 27.08 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T00:08:41Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
build-rv64-nommu-k210-virt
Desc: Builds riscv64 defconfig with NOMMU for the virt platform
Duration: 27.89 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T00:08:47Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
checkpatch
Desc: Runs checkpatch.pl on the patch
Duration: 3.65 seconds
Result: WARNING
Output:

CHECK: Alignment should match open parenthesis
#145: FILE: mm/memory.c:5219:
+		entry = pte_mkspecial(pfn_pte(zero_pfn(vmf->address),
 						vma->vm_page_prot));

CHECK: Alignment should match open parenthesis
#158: FILE: mm/migrate.c:325:
+	newpte = pte_mkspecial(pfn_pte(zero_pfn(pvmw->address),
 					pvmw->vma->vm_page_prot));

total: 0 errors, 0 warnings, 2 checks, 136 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

Commit 84e5704696fe ("mm: rename my_zero_pfn() to zero_pfn()") has style problems, please review.

NOTE: Ignored message types: ALLOC_SIZEOF_STRUCT CAMELCASE COMMIT_LOG_LONG_LINE GIT_COMMIT_ID MACRO_ARG_REUSE NO_AUTHOR_SIGN_OFF

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.
total: 0 errors, 0 warnings, 2 checks, 136 lines checked
CHECK: Alignment should match open parenthesis

linux-riscv-bot · 2026-02-13T00:10:11Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
dtb-warn-rv64
Desc: Checks for Device Tree warnings/errors
Duration: 82.69 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T00:10:13Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
header-inline
Desc: Detects static functions without inline keyword in header files
Duration: 0.24 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T00:10:16Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
kdoc
Desc: Detects for kdoc errors
Duration: 1.05 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T00:10:20Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
module-param
Desc: Detect module_param changes
Duration: 2.54 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T00:10:22Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
verify-fixes
Desc: Verifies that the Fixes: tags exist
Duration: 0.22 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T00:10:24Z

Patch 2: "[v3,2/4] mm: rename my_zero_pfn() to zero_pfn()"
verify-signedoff
Desc: Verifies that Signed-off-by: tags are correct
Duration: 0.29 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T03:11:52Z

Patch 4: "[v3,4/4] mm: cache struct page for empty_zero_page and return it from ZERO_PAGE()"
build-rv64-nommu-k210-defconfig
Desc: Builds riscv64 defconfig with NOMMU for K210
Duration: 26.76 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T03:12:22Z

Patch 4: "[v3,4/4] mm: cache struct page for empty_zero_page and return it from ZERO_PAGE()"
build-rv64-nommu-k210-virt
Desc: Builds riscv64 defconfig with NOMMU for the virt platform
Duration: 28.19 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T03:12:27Z

Patch 4: "[v3,4/4] mm: cache struct page for empty_zero_page and return it from ZERO_PAGE()"
checkpatch
Desc: Runs checkpatch.pl on the patch
Duration: 3.15 seconds
Result: WARNING
Output:

CHECK: Please use a blank line after function/struct/union/enum declarations
#216: FILE: include/linux/pgtable.h:1932:
+}
+#define ZERO_PAGE(vaddr) _zero_page(vaddr)

total: 0 errors, 0 warnings, 1 checks, 182 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

Commit 38551ee578d2 ("mm: cache struct page for empty_zero_page and return it from ZERO_PAGE()") has style problems, please review.

NOTE: Ignored message types: ALLOC_SIZEOF_STRUCT CAMELCASE COMMIT_LOG_LONG_LINE GIT_COMMIT_ID MACRO_ARG_REUSE NO_AUTHOR_SIGN_OFF

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.
total: 0 errors, 0 warnings, 1 checks, 182 lines checked
CHECK: Please use a blank line after function/struct/union/enum declarations

linux-riscv-bot · 2026-02-13T03:13:51Z

Patch 4: "[v3,4/4] mm: cache struct page for empty_zero_page and return it from ZERO_PAGE()"
dtb-warn-rv64
Desc: Checks for Device Tree warnings/errors
Duration: 82.89 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T03:13:53Z

Patch 4: "[v3,4/4] mm: cache struct page for empty_zero_page and return it from ZERO_PAGE()"
header-inline
Desc: Detects static functions without inline keyword in header files
Duration: 0.57 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T03:13:56Z

Patch 4: "[v3,4/4] mm: cache struct page for empty_zero_page and return it from ZERO_PAGE()"
kdoc
Desc: Detects for kdoc errors
Duration: 0.97 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T03:13:58Z

Patch 4: "[v3,4/4] mm: cache struct page for empty_zero_page and return it from ZERO_PAGE()"
module-param
Desc: Detect module_param changes
Duration: 0.28 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T03:14:00Z

Patch 4: "[v3,4/4] mm: cache struct page for empty_zero_page and return it from ZERO_PAGE()"
verify-fixes
Desc: Verifies that the Fixes: tags exist
Duration: 0.22 seconds
Result: PASS

linux-riscv-bot · 2026-02-13T03:14:01Z

Patch 4: "[v3,4/4] mm: cache struct page for empty_zero_page and return it from ZERO_PAGE()"
verify-signedoff
Desc: Verifies that Signed-off-by: tags are correct
Duration: 0.29 seconds
Result: PASS

Linux RISC-V bot and others added 5 commits February 12, 2026 21:04

Adding CI files

128fa5d

linux-riscv-bot force-pushed the workflow branch from 128fa5d to 12ead3f Compare February 12, 2026 23:04

linux-riscv-bot force-pushed the workflow branch 19 times, most recently from 58114d9 to 103798e Compare February 19, 2026 00:00

linux-riscv-bot closed this Feb 19, 2026

linux-riscv-bot deleted the pw1053085 branch February 19, 2026 00:01

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