mm/cma.h | 1 + mm/hugetlb_cma.h | 2 ++ mm/memcontrol-v1.h | 1 + mm/pgalloc-track.h | 3 +++ mm/shuffle.h | 2 ++ mm/swap.h | 1 + mm/vmalloc.h | 2 ++ 7 files changed, 12 insertions(+)
There are a number of internal headers local to mm/ which reference
functions and data types without including the relevant headers.
mm/vma.h is a special case that intentionally does not include additional
headers, but the others are not.
This breaks tooling like clangd (which is where I noticed this), though the
build is OK due to the C files including the headers happening to include
required dependencies.
It's better to be explicit about dependencies anyway, so add the missing
includes and fix clangd as a bonus.
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
---
mm/cma.h | 1 +
mm/hugetlb_cma.h | 2 ++
mm/memcontrol-v1.h | 1 +
mm/pgalloc-track.h | 3 +++
mm/shuffle.h | 2 ++
mm/swap.h | 1 +
mm/vmalloc.h | 2 ++
7 files changed, 12 insertions(+)
diff --git a/mm/cma.h b/mm/cma.h
index c70180c36559..ab6d39898ea5 100644
--- a/mm/cma.h
+++ b/mm/cma.h
@@ -2,6 +2,7 @@
#ifndef __MM_CMA_H__
#define __MM_CMA_H__
+#include <linux/cma.h>
#include <linux/debugfs.h>
#include <linux/kobject.h>
diff --git a/mm/hugetlb_cma.h b/mm/hugetlb_cma.h
index 3aa483573d17..730b2b4965b6 100644
--- a/mm/hugetlb_cma.h
+++ b/mm/hugetlb_cma.h
@@ -2,6 +2,8 @@
#ifndef _LINUX_HUGETLB_CMA_H
#define _LINUX_HUGETLB_CMA_H
+#include <linux/hugetlb.h>
+
#ifdef CONFIG_CMA
void hugetlb_cma_free_frozen_folio(struct folio *folio);
struct folio *hugetlb_cma_alloc_frozen_folio(int order, gfp_t gfp_mask,
diff --git a/mm/memcontrol-v1.h b/mm/memcontrol-v1.h
index 0f703f239c80..1e394269c613 100644
--- a/mm/memcontrol-v1.h
+++ b/mm/memcontrol-v1.h
@@ -4,6 +4,7 @@
#define __MM_MEMCONTROL_V1_H
#include <linux/cgroup-defs.h>
+#include <linux/memcontrol.h>
/* Cgroup v1 and v2 common declarations */
diff --git a/mm/pgalloc-track.h b/mm/pgalloc-track.h
index e9e879de8649..1a6de1358a21 100644
--- a/mm/pgalloc-track.h
+++ b/mm/pgalloc-track.h
@@ -2,6 +2,9 @@
#ifndef _LINUX_PGALLOC_TRACK_H
#define _LINUX_PGALLOC_TRACK_H
+#include <linux/mm.h>
+#include <linux/pgtable.h>
+
#if defined(CONFIG_MMU)
static inline p4d_t *p4d_alloc_track(struct mm_struct *mm, pgd_t *pgd,
unsigned long address,
diff --git a/mm/shuffle.h b/mm/shuffle.h
index 61bbcddeeee6..11bec7521ab8 100644
--- a/mm/shuffle.h
+++ b/mm/shuffle.h
@@ -2,7 +2,9 @@
// Copyright(c) 2018 Intel Corporation. All rights reserved.
#ifndef _MM_SHUFFLE_H
#define _MM_SHUFFLE_H
+
#include <linux/jump_label.h>
+#include <linux/mmzone.h>
#define SHUFFLE_ORDER MAX_PAGE_ORDER
diff --git a/mm/swap.h b/mm/swap.h
index d077e5893a42..ec580c713204 100644
--- a/mm/swap.h
+++ b/mm/swap.h
@@ -5,6 +5,7 @@
#include <linux/atomic.h> /* for atomic_long_t */
#include <linux/mm.h> /* for PAGE_SHIFT */
#include <linux/memcontrol.h> /* for mem_cgroup_swappiness() */
+#include <linux/swap.h> /* for MAX_SWAPFILES_SHIFT, struct swap_info_struct */
struct mempolicy;
struct swap_iocb;
diff --git a/mm/vmalloc.h b/mm/vmalloc.h
index dcfe30eaa80c..8866ddcff668 100644
--- a/mm/vmalloc.h
+++ b/mm/vmalloc.h
@@ -5,6 +5,8 @@
#ifndef __MM_VMALLOC_H
#define __MM_VMALLOC_H
+#include <linux/vmalloc.h>
+
#ifdef CONFIG_MMU
void __init vmalloc_init(void);
int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end,
---
base-commit: e47602c51d20a93fa1711ed896dc9480de4374d9
change-id: 20260804-fix-some-local-headers-0ebc15f34c72
Cheers,
--
Lorenzo Stoakes (ARM) <ljs@kernel.org>On Tue, Aug 4, 2026 at 6:09 PM Lorenzo Stoakes (ARM) <ljs@kernel.org> wrote: > > There are a number of internal headers local to mm/ which reference > functions and data types without including the relevant headers. > > mm/vma.h is a special case that intentionally does not include additional > headers, but the others are not. > > This breaks tooling like clangd (which is where I noticed this), though the > build is OK due to the C files including the headers happening to include > required dependencies. > > It's better to be explicit about dependencies anyway, so add the missing > includes and fix clangd as a bonus. > > Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> > --- Reviewed-by: Barry Song <baohua@kernel.org>
On 4 Aug 2026, at 6:08, Lorenzo Stoakes (ARM) wrote: > There are a number of internal headers local to mm/ which reference > functions and data types without including the relevant headers. > > mm/vma.h is a special case that intentionally does not include additional > headers, but the others are not. > > This breaks tooling like clangd (which is where I noticed this), though the > build is OK due to the C files including the headers happening to include > required dependencies. > > It's better to be explicit about dependencies anyway, so add the missing > includes and fix clangd as a bonus. > > Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> > --- > mm/cma.h | 1 + > mm/hugetlb_cma.h | 2 ++ > mm/memcontrol-v1.h | 1 + > mm/pgalloc-track.h | 3 +++ > mm/shuffle.h | 2 ++ > mm/swap.h | 1 + > mm/vmalloc.h | 2 ++ > 7 files changed, 12 insertions(+) > Acked-by: Zi Yan <ziy@nvidia.com> Best Regards, Yan, Zi
On 8/4/26 12:08, Lorenzo Stoakes (ARM) wrote: > There are a number of internal headers local to mm/ which reference > functions and data types without including the relevant headers. > > mm/vma.h is a special case that intentionally does not include additional > headers, but the others are not. > > This breaks tooling like clangd (which is where I noticed this), though the > build is OK due to the C files including the headers happening to include > required dependencies. > > It's better to be explicit about dependencies anyway, so add the missing > includes and fix clangd as a bonus. I'm curious, how did you identify these? The mm/vmalloc.h is rather easy, but I wonder about e.g., mm/shuffle.h including mmzone.h. -- Cheers, David
On Tue, Aug 04, 2026 at 12:45:22PM +0200, David Hildenbrand (Arm) wrote: > On 8/4/26 12:08, Lorenzo Stoakes (ARM) wrote: > > There are a number of internal headers local to mm/ which reference > > functions and data types without including the relevant headers. > > > > mm/vma.h is a special case that intentionally does not include additional > > headers, but the others are not. > > > > This breaks tooling like clangd (which is where I noticed this), though the > > build is OK due to the C files including the headers happening to include > > required dependencies. > > > > It's better to be explicit about dependencies anyway, so add the missing > > includes and fix clangd as a bonus. > > I'm curious, how did you identify these? The mm/vmalloc.h is rather easy, but I wonder about > e.g., mm/shuffle.h including mmzone.h. Well I got AI to look them up ;) but I pared down what it gave me to a simpler subset and checked everything so I don't consider myself in a state of slopper-sin :) [this kind of check ideas, look things up stuff I don't consider warrants an Assisted-by tag btw]. The headers for everything but shuffle.h are obvious, so that's the tricky one - it's for pg_data_t and struct zone specifically. How I discovered this with clangd initially was - Do something like 'C-c l g r' or 'C-c l g g' in emacs via LSP and it reports 'no symbols' for something I _know_ is compiled in. > > -- > Cheers, > > David -- Cheers, Lorenzo
On 8/4/26 13:02, Lorenzo Stoakes (ARM) wrote: > On Tue, Aug 04, 2026 at 12:45:22PM +0200, David Hildenbrand (Arm) wrote: >> On 8/4/26 12:08, Lorenzo Stoakes (ARM) wrote: >>> There are a number of internal headers local to mm/ which reference >>> functions and data types without including the relevant headers. >>> >>> mm/vma.h is a special case that intentionally does not include additional >>> headers, but the others are not. >>> >>> This breaks tooling like clangd (which is where I noticed this), though the >>> build is OK due to the C files including the headers happening to include >>> required dependencies. >>> >>> It's better to be explicit about dependencies anyway, so add the missing >>> includes and fix clangd as a bonus. >> >> I'm curious, how did you identify these? The mm/vmalloc.h is rather easy, but I wonder about >> e.g., mm/shuffle.h including mmzone.h. > > Well I got AI to look them up ;) but I pared down what it gave me to a simpler > subset and checked everything so I don't consider myself in a state of > slopper-sin :) > > [this kind of check ideas, look things up stuff I don't consider warrants an > Assisted-by tag btw]. > > The headers for everything but shuffle.h are obvious, so that's the tricky one - > it's for pg_data_t and struct zone specifically. > > How I discovered this with clangd initially was - Do something like 'C-c l g r' or > 'C-c l g g' in emacs via LSP and it reports 'no symbols' for something I _know_ is > compiled in. emacs ... there's your problem :P Thanks for the explanation, I'm afraid this might become a whack-a-mole without a proper way to detect this automatically. But that does not really seem doable easily. Acked-by: David Hildenbrand (Arm) <david@kernel.org> -- Cheers, David
On 8/4/26 12:45, David Hildenbrand (Arm) wrote: > On 8/4/26 12:08, Lorenzo Stoakes (ARM) wrote: >> There are a number of internal headers local to mm/ which reference >> functions and data types without including the relevant headers. >> >> mm/vma.h is a special case that intentionally does not include additional >> headers, but the others are not. >> >> This breaks tooling like clangd (which is where I noticed this), though the >> build is OK due to the C files including the headers happening to include >> required dependencies. >> >> It's better to be explicit about dependencies anyway, so add the missing >> includes and fix clangd as a bonus. > > I'm curious, how did you identify these? The mm/vmalloc.h is rather easy, but I wonder about > e.g., mm/shuffle.h including mmzone.h. > To clarify, I have clangd running behind a vim plugin, and so far it just worked. I had to generate a weird XML at some point that does magical things for clangd. So I'm curious how to invoke clangd manually to actually get these reports. -- Cheers, David
On Tue, Aug 04, 2026 at 12:51:40PM +0200, David Hildenbrand (Arm) wrote: > On 8/4/26 12:45, David Hildenbrand (Arm) wrote: > > On 8/4/26 12:08, Lorenzo Stoakes (ARM) wrote: > >> There are a number of internal headers local to mm/ which reference > >> functions and data types without including the relevant headers. > >> > >> mm/vma.h is a special case that intentionally does not include additional > >> headers, but the others are not. > >> > >> This breaks tooling like clangd (which is where I noticed this), though the > >> build is OK due to the C files including the headers happening to include > >> required dependencies. > >> > >> It's better to be explicit about dependencies anyway, so add the missing > >> includes and fix clangd as a bonus. > > > > I'm curious, how did you identify these? The mm/vmalloc.h is rather easy, but I wonder about > > e.g., mm/shuffle.h including mmzone.h. > > > > To clarify, I have clangd running behind a vim plugin, and so far it just worked. > > I had to generate a weird XML at some point that does magical things for clangd. Well for me I get the kernel build to generate compiler_commands.json and use that via: scripts/clang-tools/gen_compile_commands.py vmlinux.a arch/x86/boot/ In a build script. But maybe I need your weird XML... I do get frustrated that it limits things to what I happened to compile. It'd be nice to get it to index literally everything somehow. > > So I'm curious how to invoke clangd manually to actually get these reports. See other reply, it's just that I noticed missing symbols. Actually this happened with vma.h (I sloppily got AI to figure out any other cases) which _intentionally_ doesn't have includes. But clangd lets you work around that in .clangd: If: PathMatch: mm/vma\.h CompileFlags: Add: [-include, mm/vma_internal.h] :) > > -- > Cheers, > > David -- Cheers, Lorenzo
On 8/4/26 13:05, Lorenzo Stoakes (ARM) wrote: > On Tue, Aug 04, 2026 at 12:51:40PM +0200, David Hildenbrand (Arm) wrote: >> On 8/4/26 12:45, David Hildenbrand (Arm) wrote: >>> >>> I'm curious, how did you identify these? The mm/vmalloc.h is rather easy, but I wonder about >>> e.g., mm/shuffle.h including mmzone.h. >>> >> >> To clarify, I have clangd running behind a vim plugin, and so far it just worked. >> >> I had to generate a weird XML at some point that does magical things for clangd. > > Well for me I get the kernel build to generate compiler_commands.json and use > that via: > > scripts/clang-tools/gen_compile_commands.py vmlinux.a arch/x86/boot/ > > In a build script. > > But maybe I need your weird XML... I do get frustrated that it limits things to > what I happened to compile. It'd be nice to get it to index literally everything > somehow. Nah, it was that magical json I had in mind. > >> >> So I'm curious how to invoke clangd manually to actually get these reports. > > See other reply, it's just that I noticed missing symbols. > > Actually this happened with vma.h (I sloppily got AI to figure out any other > cases) which _intentionally_ doesn't have includes. > > But clangd lets you work around that in .clangd: > > If: > PathMatch: mm/vma\.h > CompileFlags: > Add: [-include, mm/vma_internal.h] > > :) I was hoping for an easy-to-run script that complains, instead of people just randomly running into "missing symbols" and then having to fix it. But there doesn't seem to be a low hanging fruit. -- Cheers, David
On 8/4/26 12:08, Lorenzo Stoakes (ARM) wrote: > There are a number of internal headers local to mm/ which reference > functions and data types without including the relevant headers. > > mm/vma.h is a special case that intentionally does not include additional > headers, but the others are not. > > This breaks tooling like clangd (which is where I noticed this), though the > build is OK due to the C files including the headers happening to include > required dependencies. > > It's better to be explicit about dependencies anyway, so add the missing > includes and fix clangd as a bonus. > > Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> > --- > mm/cma.h | 1 + > mm/hugetlb_cma.h | 2 ++ > mm/memcontrol-v1.h | 1 + > mm/pgalloc-track.h | 3 +++ > mm/shuffle.h | 2 ++ > mm/swap.h | 1 + > mm/vmalloc.h | 2 ++ > 7 files changed, 12 insertions(+) > > diff --git a/mm/cma.h b/mm/cma.h > index c70180c36559..ab6d39898ea5 100644 > --- a/mm/cma.h > +++ b/mm/cma.h > @@ -2,6 +2,7 @@ > #ifndef __MM_CMA_H__ > #define __MM_CMA_H__ > > +#include <linux/cma.h> > #include <linux/debugfs.h> > #include <linux/kobject.h> > > diff --git a/mm/hugetlb_cma.h b/mm/hugetlb_cma.h > index 3aa483573d17..730b2b4965b6 100644 > --- a/mm/hugetlb_cma.h > +++ b/mm/hugetlb_cma.h > @@ -2,6 +2,8 @@ > #ifndef _LINUX_HUGETLB_CMA_H > #define _LINUX_HUGETLB_CMA_H > > +#include <linux/hugetlb.h> > + > #ifdef CONFIG_CMA > void hugetlb_cma_free_frozen_folio(struct folio *folio); > struct folio *hugetlb_cma_alloc_frozen_folio(int order, gfp_t gfp_mask, > diff --git a/mm/memcontrol-v1.h b/mm/memcontrol-v1.h > index 0f703f239c80..1e394269c613 100644 > --- a/mm/memcontrol-v1.h > +++ b/mm/memcontrol-v1.h > @@ -4,6 +4,7 @@ > #define __MM_MEMCONTROL_V1_H > > #include <linux/cgroup-defs.h> > +#include <linux/memcontrol.h> > > /* Cgroup v1 and v2 common declarations */ > > diff --git a/mm/pgalloc-track.h b/mm/pgalloc-track.h > index e9e879de8649..1a6de1358a21 100644 > --- a/mm/pgalloc-track.h > +++ b/mm/pgalloc-track.h > @@ -2,6 +2,9 @@ > #ifndef _LINUX_PGALLOC_TRACK_H > #define _LINUX_PGALLOC_TRACK_H > > +#include <linux/mm.h> > +#include <linux/pgtable.h> > + > #if defined(CONFIG_MMU) > static inline p4d_t *p4d_alloc_track(struct mm_struct *mm, pgd_t *pgd, > unsigned long address, > diff --git a/mm/shuffle.h b/mm/shuffle.h > index 61bbcddeeee6..11bec7521ab8 100644 > --- a/mm/shuffle.h > +++ b/mm/shuffle.h > @@ -2,7 +2,9 @@ > // Copyright(c) 2018 Intel Corporation. All rights reserved. > #ifndef _MM_SHUFFLE_H > #define _MM_SHUFFLE_H > + > #include <linux/jump_label.h> > +#include <linux/mmzone.h> > > #define SHUFFLE_ORDER MAX_PAGE_ORDER > > diff --git a/mm/swap.h b/mm/swap.h > index d077e5893a42..ec580c713204 100644 > --- a/mm/swap.h > +++ b/mm/swap.h > @@ -5,6 +5,7 @@ > #include <linux/atomic.h> /* for atomic_long_t */ > #include <linux/mm.h> /* for PAGE_SHIFT */ > #include <linux/memcontrol.h> /* for mem_cgroup_swappiness() */ > +#include <linux/swap.h> /* for MAX_SWAPFILES_SHIFT, struct swap_info_struct */ > > struct mempolicy; > struct swap_iocb; > diff --git a/mm/vmalloc.h b/mm/vmalloc.h > index dcfe30eaa80c..8866ddcff668 100644 > --- a/mm/vmalloc.h > +++ b/mm/vmalloc.h > @@ -5,6 +5,8 @@ > #ifndef __MM_VMALLOC_H > #define __MM_VMALLOC_H > > +#include <linux/vmalloc.h> > + > #ifdef CONFIG_MMU > void __init vmalloc_init(void); > int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, > > --- > base-commit: e47602c51d20a93fa1711ed896dc9480de4374d9 > change-id: 20260804-fix-some-local-headers-0ebc15f34c72 > > Cheers,
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