The branch main has been updated by vexeduxr:
URL:
https://cgit.FreeBSD.org/src/commit/?id=29418225611689d5dafeff1f0b7e2f170305ca90
commit 29418225611689d5dafeff1f0b7e2f170305ca90
Author: Ahmad Khalifa <vexed...@freebsd.org>
AuthorDate: 2025-05-21 20:57:33 +0000
Commit: Ahmad Khalifa <vexed...@freebsd.org>
CommitDate: 2025-06-22 03:49:32 +0000
sys: provide the kernel's pa when dumping on amd64
Provide the kernel's physical address in an ELF section when doing a
full memory dump on amd64. This allows libkvm to figure out where the
kernel was loaded in physical memory.
Reviewed by: markj
Approved by: imp (mentor)
Pull Request: https://github.com/freebsd/freebsd-src/pull/1706
---
sys/sys/elf_common.h | 4 ++--
sys/x86/include/dump.h | 8 ++++++++
sys/x86/x86/dump_machdep.c | 26 ++++++++++++++++++++++++++
3 files changed, 36 insertions(+), 2 deletions(-)
diff --git a/sys/sys/elf_common.h b/sys/sys/elf_common.h
index 1c33b55fc5b6..a5e605624e1e 100644
--- a/sys/sys/elf_common.h
+++ b/sys/sys/elf_common.h
@@ -554,8 +554,8 @@ typedef struct {
#define PT_GNU_EH_FRAME 0x6474e550
#define PT_GNU_STACK 0x6474e551
#define PT_GNU_RELRO 0x6474e552
-#define PT_DUMP_DELTA 0x6fb5d000 /* va->pa map for kernel dumps
- (currently arm). */
+#define PT_DUMP_DELTA 0x6fb5d000 /* va->pa map for arm and amd64
kernel
+ dumps */
#define PT_LOSUNW 0x6ffffffa
#define PT_SUNWBSS 0x6ffffffa /* Sun Specific segment */
#define PT_SUNWSTACK 0x6ffffffb /* describes the stack segment
*/
diff --git a/sys/x86/include/dump.h b/sys/x86/include/dump.h
index 7f4caf9e8292..cdd07f32703c 100644
--- a/sys/x86/include/dump.h
+++ b/sys/x86/include/dump.h
@@ -38,7 +38,11 @@
/* 20 phys_avail entry pairs correspond to 10 pa's */
#define DUMPSYS_MD_PA_NPAIRS 10
+#ifdef __amd64__
+#define DUMPSYS_NUM_AUX_HDRS 1
+#else
#define DUMPSYS_NUM_AUX_HDRS 0
+#endif
/* How often to check the dump progress bar? */
#define DUMPSYS_PB_CHECK_BITS 24 /* Every 16MB */
@@ -71,12 +75,16 @@ dumpsys_unmap_chunk(vm_paddr_t pa, size_t s, void *va)
dumpsys_gen_unmap_chunk(pa, s, va);
}
+#ifdef __amd64__
+int dumpsys_write_aux_headers(struct dumperinfo *di);
+#else
static inline int
dumpsys_write_aux_headers(struct dumperinfo *di)
{
return (dumpsys_gen_write_aux_headers(di));
}
+#endif
static inline int
dumpsys(struct dumperinfo *di)
diff --git a/sys/x86/x86/dump_machdep.c b/sys/x86/x86/dump_machdep.c
index 866247610c07..71598e2c9808 100644
--- a/sys/x86/x86/dump_machdep.c
+++ b/sys/x86/x86/dump_machdep.c
@@ -37,6 +37,13 @@
#include <vm/vm.h>
#include <vm/pmap.h>
+#ifdef __amd64__
+#include <machine/elf.h>
+#include <machine/vmparam.h>
+#include <machine/md_var.h>
+#include <machine/dump.h>
+#endif
+
int do_minidump = 1;
SYSCTL_INT(_debug, OID_AUTO, minidump, CTLFLAG_RWTUN, &do_minidump, 0,
"Enable mini crash dumps");
@@ -52,3 +59,22 @@ dumpsys_map_chunk(vm_paddr_t pa, size_t chunk, void **va)
*va = pmap_kenter_temporary(trunc_page(a), i);
}
}
+
+#ifdef __amd64__
+int
+dumpsys_write_aux_headers(struct dumperinfo *di)
+{
+ Elf_Phdr phdr;
+
+ phdr.p_type = PT_DUMP_DELTA;
+ phdr.p_flags = PF_R;
+ phdr.p_offset = 0;
+ phdr.p_vaddr = KERNBASE;
+ phdr.p_paddr = kernphys;
+ phdr.p_filesz = 0;
+ phdr.p_memsz = 0;
+ phdr.p_align = KERNLOAD;
+
+ return (dumpsys_buf_write(di, (char *)&phdr, sizeof(phdr)));
+}
+#endif
