From: Christian Brauner <brauner@kernel.org>
To: linux-fsdevel@vger.kernel.org
Cc: Jacob Lalonde <jalalonde@meta.com>,
Josef Bacik <josef@toxicpanda.com>, Jann Horn <jannh@google.com>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Jan Kara <jack@suse.cz>,
Andrew Morton <akpm@linux-foundation.org>,
David Hildenbrand <david@kernel.org>,
Lorenzo Stoakes <ljs@kernel.org>,
"Liam R. Howlett" <liam@infradead.org>,
Vlastimil Babka <vbabka@kernel.org>,
Mike Rapoport <rppt@kernel.org>,
Suren Baghdasaryan <surenb@google.com>,
Michal Hocko <mhocko@suse.com>,
Omar Sandoval <osandov@osandov.com>,
Jacob Lalonde <jalalonde@fb.com>, Shuah Khan <shuah@kernel.org>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
linux-kselftest@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
"Christian Brauner (Amutable)" <brauner@kernel.org>
Subject: [PATCH 2/6] tools: sync coredump.h header
Date: Fri, 21 Aug 2026 13:52:03 +0200 [thread overview]
Message-ID: <20260821-work-coredump-filter-v1-2-91f9a73ef03e@kernel.org> (raw)
In-Reply-To: <20260821-work-coredump-filter-v1-0-91f9a73ef03e@kernel.org>
Sync the headers for the selftests.
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
---
tools/include/uapi/linux/coredump.h | 70 +++++++++++++++++++++++++++++++++++--
1 file changed, 68 insertions(+), 2 deletions(-)
diff --git a/tools/include/uapi/linux/coredump.h b/tools/include/uapi/linux/coredump.h
index f3771861ca48..6d0c53b534ea 100644
--- a/tools/include/uapi/linux/coredump.h
+++ b/tools/include/uapi/linux/coredump.h
@@ -16,6 +16,9 @@
* requires COREDUMP_KERNEL
* @COREDUMP_SPARSE: describe the holes in the coredump as zero records
* instead of transferring them; requires COREDUMP_RECORDS
+ * @COREDUMP_MEMORY_TYPES: dump the memory types in
+ * coredump_ack->memory_types instead of the ones
+ * the task selected; requires COREDUMP_KERNEL
*/
enum {
COREDUMP_KERNEL = (1ULL << 0),
@@ -24,6 +27,37 @@ enum {
COREDUMP_WAIT = (1ULL << 3),
COREDUMP_RECORDS = (1ULL << 4),
COREDUMP_SPARSE = (1ULL << 5),
+ COREDUMP_MEMORY_TYPES = (1ULL << 6),
+};
+
+/**
+ * coredump memory types
+ * @COREDUMP_MEMORY_ANON_PRIVATE: anonymous private memory
+ * @COREDUMP_MEMORY_ANON_SHARED: anonymous shared memory
+ * @COREDUMP_MEMORY_FILE_PRIVATE: file-backed private memory
+ * @COREDUMP_MEMORY_FILE_SHARED: file-backed shared memory
+ * @COREDUMP_MEMORY_ELF_HEADERS: the first page of a file-backed private
+ * mapping that starts an ELF file
+ * @COREDUMP_MEMORY_HUGETLB_PRIVATE: hugetlb private memory
+ * @COREDUMP_MEMORY_HUGETLB_SHARED: hugetlb shared memory
+ * @COREDUMP_MEMORY_DAX_PRIVATE: DAX private memory
+ * @COREDUMP_MEMORY_DAX_SHARED: DAX shared memory
+ *
+ * A bitmask of memory types a coredump may request to be included. New
+ * memory type bits must ensure that they do not steal memory from an
+ * existing one so a coredump server will continue to get the same
+ * coredumps even if a new bit is introduced.
+ */
+enum {
+ COREDUMP_MEMORY_ANON_PRIVATE = (1ULL << 0),
+ COREDUMP_MEMORY_ANON_SHARED = (1ULL << 1),
+ COREDUMP_MEMORY_FILE_PRIVATE = (1ULL << 2),
+ COREDUMP_MEMORY_FILE_SHARED = (1ULL << 3),
+ COREDUMP_MEMORY_ELF_HEADERS = (1ULL << 4),
+ COREDUMP_MEMORY_HUGETLB_PRIVATE = (1ULL << 5),
+ COREDUMP_MEMORY_HUGETLB_SHARED = (1ULL << 6),
+ COREDUMP_MEMORY_DAX_PRIVATE = (1ULL << 7),
+ COREDUMP_MEMORY_DAX_SHARED = (1ULL << 8),
};
/**
@@ -31,6 +65,8 @@ enum {
* @size: size of struct coredump_req
* @size_ack: known size of struct coredump_ack on this kernel
* @mask: supported features
+ * @memory_types: the memory types the task selected
+ * @memory_types_mask: the memory types this kernel knows
*
* When a coredump happens the kernel will connect to the coredump
* socket and send a coredump request to the coredump server. The @size
@@ -49,15 +85,27 @@ enum {
* struct coredump_ack the kernel knows. Userspace may only send up to
* coredump_req->size_ack bytes to the kernel and must set
* coredump_ack->size accordingly.
+ *
+ * @memory_types is set to the default memory types that are included in
+ * the coredump. This can be overridden by raising bits in
+ * coredump_ack->memory_types.
+ *
+ * @memory_types_mask contains a bitmask of all memory types the kernel
+ * knows about. A coredump server may only raise bits in
+ * coredump_ack->memory_types that are raised in
+ * coredump_req->memory_types_mask.
*/
struct coredump_req {
__u32 size;
__u32 size_ack;
__u64 mask;
+ __u64 memory_types;
+ __u64 memory_types_mask;
};
enum {
COREDUMP_REQ_SIZE_VER0 = 16U, /* size of first published struct */
+ COREDUMP_REQ_SIZE_VER1 = 32U, /* memory_types and memory_types_mask added */
};
/**
@@ -65,6 +113,8 @@ enum {
* @size: size of the struct
* @spare: unused
* @mask: features kernel is supposed to use
+ * @memory_types: memory types to dump, only with COREDUMP_MEMORY_TYPES
+ * in @mask
*
* The @size member must be set to the size of struct coredump_ack. It
* may never exceed what the kernel returned in coredump_req->size_ack
@@ -74,15 +124,30 @@ enum {
* The @mask member must be set to the features the coredump server
* wants the kernel to use. Only bits the kernel returned in
* coredump_req->mask may be set.
+ *
+ * If COREDUMP_MEMORY_TYPES is raised in @mask the kernel dumps the
+ * memory types set in the @memory_types mask. Zero is valid and dumps
+ * no memory apart from the mappings that are always dumped.
+ *
+ * Note that memory a task excluded via MADV_DONTDUMP is always left
+ * out. A coredump server wanting to add or drop memory types instead of
+ * outright replacing it should simply copy coredump_req->memory_types
+ * and then mask off or raise types as needed.
+ *
+ * Note that @memory_types must be zero if COREDUMP_MEMORY_TYPES isn't
+ * raised. COREDUMP_MEMORY_TYPES requires COREDUMP_KERNEL and an ack of
+ * at least COREDUMP_ACK_SIZE_VER1 bytes.
*/
struct coredump_ack {
__u32 size;
__u32 spare;
__u64 mask;
+ __u64 memory_types;
};
enum {
COREDUMP_ACK_SIZE_VER0 = 16U, /* size of first published struct */
+ COREDUMP_ACK_SIZE_VER1 = 24U, /* memory_types added */
};
/**
@@ -90,11 +155,12 @@ enum {
*
* The kernel will place a single byte on the coredump socket. The
* markers notify userspace whether the coredump ack succeeded or
- * failed.
+ * failed. After any marker other than COREDUMP_MARK_REQACK the kernel
+ * closes the connection and no coredump is generated.
*
* @COREDUMP_MARK_MINSIZE: the provided coredump_ack size was too small
* @COREDUMP_MARK_MAXSIZE: the provided coredump_ack size was too big
- * @COREDUMP_MARK_UNSUPPORTED: the provided coredump_ack mask was invalid
+ * @COREDUMP_MARK_UNSUPPORTED: the provided coredump_ack mask or memory types were invalid
* @COREDUMP_MARK_CONFLICTING: the provided coredump_ack mask has conflicting options
* @COREDUMP_MARK_REQACK: the coredump request and ack was successful
* @__COREDUMP_MARK_MAX: the maximum coredump mark value
--
2.53.0
next prev parent reply other threads:[~2026-08-21 11:52 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-21 11:52 [PATCH 0/6] coredump: select memory types per request Christian Brauner
2026-08-21 11:52 ` [PATCH 1/6] coredump: select memory types to include Christian Brauner
2026-08-21 11:52 ` Christian Brauner [this message]
2026-08-21 11:52 ` [PATCH 3/6] selftests/coredump: simplify the refusal tests Christian Brauner
2026-08-21 11:52 ` [PATCH 4/6] selftests/coredump: test COREDUMP_MEMORY_TYPES Christian Brauner
2026-08-21 11:52 ` [PATCH 5/6] selftests/coredump: improve coredump size negotiation tests Christian Brauner
2026-08-21 11:52 ` [PATCH 6/6] selftests/coredump: test failed handshakes Christian Brauner
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260821-work-coredump-filter-v1-2-91f9a73ef03e@kernel.org \
--to=brauner@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=david@kernel.org \
--cc=jack@suse.cz \
--cc=jalalonde@fb.com \
--cc=jalalonde@meta.com \
--cc=jannh@google.com \
--cc=josef@toxicpanda.com \
--cc=liam@infradead.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=ljs@kernel.org \
--cc=mhocko@suse.com \
--cc=osandov@osandov.com \
--cc=rppt@kernel.org \
--cc=shuah@kernel.org \
--cc=surenb@google.com \
--cc=vbabka@kernel.org \
--cc=viro@zeniv.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox