Author: bdragon
Date: Thu May 7 19:32:49 2020
New Revision: 360794
URL: https://svnweb.freebsd.org/changeset/base/360794
Log:
[PowerPC] kernel ifunc support for powerpc*, fix ppc64 relocation oddities.
This is a general cleanup of the relocatable kernel support on powerpc,
needed to enable kernel ifuncs.
* Fix some relocatable issues in the kernel linker, and change to using
a RELOCATABLE_KERNEL #define instead of #ifdef __powerpc__ for parts that
other platforms can use in the future if they wish to have ET_DYN kernels.
* Get rid of the DB_STOFFS hack now that the kernel is relocated to the DMAP
properly across the board on powerpc64.
* Add powerpc64 and powerpc32 ifunc functionality.
* Allow AIM64 virtual mode OF kernels to run from the DMAP like other AIM64
by implementing a virtual mode restart. This fixes the runtime address on
PowerMac G5.
* Fix symbol relocation problems on post-relocation kernels by relocating
the symbol table.
* Add an undocumented method for supplying kernel symbols on powernv and
other powerpc machines using linux-style kernel/initrd loading -- If
you pass the kernel in as the initrd as well, the copy resident in initrd
will be used as a source for symbols when initializing the debugger.
This method is subject to removal once we have a better way of doing this.
Approved by: jhibbits
Relnotes: yes
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D23156
Modified:
head/sys/conf/kern.pre.mk
head/sys/conf/ldscript.powerpc
head/sys/conf/ldscript.powerpc64
head/sys/conf/ldscript.powerpcspe
head/sys/kern/link_elf.c
head/sys/powerpc/aim/aim_machdep.c
head/sys/powerpc/aim/locore64.S
head/sys/powerpc/include/db_machdep.h
head/sys/powerpc/include/param.h
head/sys/powerpc/ofw/ofw_initrd.c
head/sys/powerpc/powerpc/elf32_machdep.c
head/sys/powerpc/powerpc/elf64_machdep.c
head/sys/powerpc/powerpc/machdep.c
Modified: head/sys/conf/kern.pre.mk
==============================================================================
--- head/sys/conf/kern.pre.mk Thu May 7 19:19:39 2020 (r360793)
+++ head/sys/conf/kern.pre.mk Thu May 7 19:32:49 2020 (r360794)
@@ -161,9 +161,9 @@ LDFLAGS+= --build-id=sha1
.endif
.if (${MACHINE_CPUARCH} == "aarch64" || ${MACHINE_CPUARCH} == "amd64" || \
- ${MACHINE_CPUARCH} == "i386") && \
+ ${MACHINE_CPUARCH} == "i386" || ${MACHINE} == "powerpc") && \
defined(LINKER_FEATURES) && ${LINKER_FEATURES:Mifunc} == ""
-.error amd64/arm64/i386 kernel requires linker ifunc support
+.error amd64/arm64/i386/ppc* kernel requires linker ifunc support
.endif
.if ${MACHINE_CPUARCH} == "amd64"
LDFLAGS+= -z max-page-size=2097152
Modified: head/sys/conf/ldscript.powerpc
==============================================================================
--- head/sys/conf/ldscript.powerpc Thu May 7 19:19:39 2020
(r360793)
+++ head/sys/conf/ldscript.powerpc Thu May 7 19:32:49 2020
(r360794)
@@ -6,6 +6,11 @@ OUTPUT_ARCH(powerpc)
ENTRY(__start)
SEARCH_DIR(/usr/lib);
PROVIDE (__stack = 0);
+PHDRS
+{
+ kernel PT_LOAD;
+ dynamic PT_DYNAMIC;
+}
SECTIONS
{
/* Read-only sections, merged into text segment: */
@@ -21,7 +26,7 @@ SECTIONS
/* .gnu.warning sections are handled specially by elf32.em. */
*(.gnu.warning)
*(.gnu.linkonce.t*)
- } =0
+ } :kernel =0
_etext = .;
PROVIDE (etext = .);
@@ -77,7 +82,7 @@ SECTIONS
.got.plt : { *(.got.plt) }
- .dynamic : { *(.dynamic) }
+ .dynamic : { *(.dynamic) } :kernel :dynamic
/* Put .ctors and .dtors next to the .got2 section, so that the pointers
get relocated with -mrelocatable. Also put in the .fixup pointers.
The current compiler no longer needs this, but keep it around for 2.7.2
*/
@@ -96,7 +101,7 @@ SECTIONS
/* We want the small data sections together, so single-instruction offsets
can access them all, and initialized data all before uninitialized, so
we can shorten the on-disk segment size. */
- .sdata : { *(.sdata) }
+ .sdata : { *(.sdata) } :kernel
_edata = .;
PROVIDE (edata = .);
.sbss :
Modified: head/sys/conf/ldscript.powerpc64
==============================================================================
--- head/sys/conf/ldscript.powerpc64 Thu May 7 19:19:39 2020
(r360793)
+++ head/sys/conf/ldscript.powerpc64 Thu May 7 19:32:49 2020
(r360794)
@@ -8,15 +8,15 @@ SEARCH_DIR(/usr/lib);
PROVIDE (__stack = 0);
PHDRS
{
- text PT_LOAD ;
- dynamic PT_DYNAMIC ;
+ kernel PT_LOAD;
+ dynamic PT_DYNAMIC;
}
SECTIONS
{
/* Low-address wrapper for bootloaders (kexec/kboot) that can't parse ELF */
. = kernbase - 0x100;
- .kboot : { *(.text.kboot) } :text
+ .kboot : { *(.text.kboot) } :kernel
/* Read-only sections, merged into text segment: */
. = kernbase;
@@ -106,7 +106,7 @@ SECTIONS
.got : ALIGN(8) { __tocbase = .; *(.got) }
.toc : ALIGN(8) { *(.toc) }
- .dynamic : { *(.dynamic) } :text :dynamic
+ .dynamic : { *(.dynamic) } :kernel :dynamic
/* Put .ctors and .dtors next to the .got2 section, so that the pointers
get relocated with -mrelocatable. Also put in the .fixup pointers.
The current compiler no longer needs this, but keep it around for 2.7.2
*/
@@ -125,7 +125,7 @@ SECTIONS
/* We want the small data sections together, so single-instruction offsets
can access them all, and initialized data all before uninitialized, so
we can shorten the on-disk segment size. */
- .sdata : { *(.sdata) }
+ .sdata : { *(.sdata) } :kernel
_edata = .;
PROVIDE (edata = .);
.sbss :
Modified: head/sys/conf/ldscript.powerpcspe
==============================================================================
--- head/sys/conf/ldscript.powerpcspe Thu May 7 19:19:39 2020
(r360793)
+++ head/sys/conf/ldscript.powerpcspe Thu May 7 19:32:49 2020
(r360794)
@@ -6,6 +6,11 @@ OUTPUT_ARCH(powerpc)
ENTRY(__start)
SEARCH_DIR(/usr/lib);
PROVIDE (__stack = 0);
+PHDRS
+{
+ kernel PT_LOAD;
+ dynamic PT_DYNAMIC;
+}
SECTIONS
{
/* Read-only sections, merged into text segment: */
@@ -21,7 +26,7 @@ SECTIONS
/* .gnu.warning sections are handled specially by elf32.em. */
*(.gnu.warning)
*(.gnu.linkonce.t*)
- } =0
+ } :kernel =0
_etext = .;
PROVIDE (etext = .);
@@ -78,7 +83,7 @@ SECTIONS
.got.plt : { *(.got.plt) }
- .dynamic : { *(.dynamic) }
+ .dynamic : { *(.dynamic) } :kernel :dynamic
/* Put .ctors and .dtors next to the .got2 section, so that the pointers
get relocated with -mrelocatable. Also put in the .fixup pointers.
The current compiler no longer needs this, but keep it around for 2.7.2
*/
@@ -97,7 +102,7 @@ SECTIONS
/* We want the small data sections together, so single-instruction offsets
can access them all, and initialized data all before uninitialized, so
we can shorten the on-disk segment size. */
- .sdata : { *(.sdata) }
+ .sdata : { *(.sdata) } :kernel
_edata = .;
PROVIDE (edata = .);
.sbss :
Modified: head/sys/kern/link_elf.c
==============================================================================
--- head/sys/kern/link_elf.c Thu May 7 19:19:39 2020 (r360793)
+++ head/sys/kern/link_elf.c Thu May 7 19:32:49 2020 (r360794)
@@ -388,7 +388,9 @@ link_elf_link_common_finish(linker_file_t lf)
return (0);
}
+#ifdef RELOCATABLE_KERNEL
extern vm_offset_t __startkernel, __endkernel;
+#endif
static unsigned long kern_relbase = KERNBASE;
@@ -424,7 +426,7 @@ link_elf_init(void* arg)
ef = (elf_file_t) linker_kernel_file;
ef->preloaded = 1;
-#ifdef __powerpc__
+#ifdef RELOCATABLE_KERNEL
ef->address = (caddr_t) (__startkernel - KERNBASE);
#else
ef->address = 0;
@@ -436,7 +438,7 @@ link_elf_init(void* arg)
if (dp != NULL)
parse_dynamic(ef);
-#ifdef __powerpc__
+#ifdef RELOCATABLE_KERNEL
linker_kernel_file->address = (caddr_t)__startkernel;
linker_kernel_file->size = (intptr_t)(__endkernel - __startkernel);
kern_relbase = (unsigned long)__startkernel;
@@ -1860,7 +1862,7 @@ link_elf_strtab_get(linker_file_t lf, caddr_t *strtab)
return (ef->ddbstrcnt);
}
-#if defined(__i386__) || defined(__amd64__) || defined(__aarch64__)
+#if defined(__i386__) || defined(__amd64__) || defined(__aarch64__) ||
defined(__powerpc__)
/*
* Use this lookup routine when performing relocations early during boot.
* The generic lookup routine depends on kobj, which is not initialized
@@ -1896,8 +1898,14 @@ link_elf_ireloc(caddr_t kmdp)
ef->modptr = kmdp;
ef->dynamic = (Elf_Dyn *)&_DYNAMIC;
- parse_dynamic(ef);
+
+#ifdef RELOCATABLE_KERNEL
+ ef->address = (caddr_t) (__startkernel - KERNBASE);
+#else
ef->address = 0;
+#endif
+ parse_dynamic(ef);
+
link_elf_preload_parse_symbols(ef);
relocate_file1(ef, elf_lookup_ifunc, elf_reloc, true);
}
Modified: head/sys/powerpc/aim/aim_machdep.c
==============================================================================
--- head/sys/powerpc/aim/aim_machdep.c Thu May 7 19:19:39 2020
(r360793)
+++ head/sys/powerpc/aim/aim_machdep.c Thu May 7 19:32:49 2020
(r360794)
@@ -161,6 +161,7 @@ extern void *dsmisstrap, *dsmisssize;
extern void *ap_pcpu;
extern void __restartkernel(vm_offset_t, vm_offset_t, vm_offset_t, void *,
uint32_t, register_t offset, register_t msr);
+extern void __restartkernel_virtual(vm_offset_t, vm_offset_t, vm_offset_t,
void *, uint32_t, register_t offset, register_t msr);
void aim_early_init(vm_offset_t fdt, vm_offset_t toc, vm_offset_t ofentry,
void *mdp, uint32_t mdp_cookie);
@@ -184,13 +185,22 @@ aim_early_init(vm_offset_t fdt, vm_offset_t toc, vm_of
#ifdef __powerpc64__
/*
- * If in real mode, relocate to high memory so that the kernel
+ * Relocate to high memory so that the kernel
* can execute from the direct map.
+ *
+ * If we are in virtual mode already, use a special entry point
+ * that sets up a temporary DMAP to execute from until we can
+ * properly set up the MMU.
*/
- if (!(mfmsr() & PSL_DR) &&
- (vm_offset_t)&aim_early_init < DMAP_BASE_ADDRESS)
- __restartkernel(fdt, 0, ofentry, mdp, mdp_cookie,
- DMAP_BASE_ADDRESS, mfmsr());
+ if ((vm_offset_t)&aim_early_init < DMAP_BASE_ADDRESS) {
+ if (mfmsr() & PSL_DR) {
+ __restartkernel_virtual(fdt, 0, ofentry, mdp,
+ mdp_cookie, DMAP_BASE_ADDRESS, mfmsr());
+ } else {
+ __restartkernel(fdt, 0, ofentry, mdp, mdp_cookie,
+ DMAP_BASE_ADDRESS, mfmsr());
+ }
+ }
#endif
/* Various very early CPU fix ups */
Modified: head/sys/powerpc/aim/locore64.S
==============================================================================
--- head/sys/powerpc/aim/locore64.S Thu May 7 19:19:39 2020
(r360793)
+++ head/sys/powerpc/aim/locore64.S Thu May 7 19:32:49 2020
(r360794)
@@ -200,6 +200,57 @@ ASENTRY_NOPROF(__start)
/* Unreachable */
b .
+ASENTRY_NOPROF(__restartkernel_virtual)
+ /*
+ * When coming in via this entry point, we need to alter the SLB to
+ * shadow the segment register emulation entries in DMAP space.
+ * We need to do this dance because we are running with virtual-mode
+ * OpenFirmware and have not yet taken over the MMU.
+ *
+ * Assumptions:
+ * 1) The kernel is currently identity-mapped.
+ * 2) We are currently executing at an address compatible with
+ * real mode.
+ * 3) The first 16 SLB entries are emulating SRs.
+ * 4) The rest of the SLB is not in use.
+ * 5) OpenFirmware is not manipulating the SLB at runtime.
+ * 6) We are running on 64-bit AIM.
+ *
+ * Tested on a G5.
+ */
+ mfmsr %r14
+ /* Switch to real mode because we are about to mess with the SLB. */
+ andi. %r14, %r14, ~(PSL_DR|PSL_IR|PSL_ME|PSL_RI)@l
+ mtmsr %r14
+ isync
+ /* Prepare variables for later use. */
+ li %r14, 0
+ li %r18, 0
+ oris %r18, %r18, 0xc000
+ sldi %r18, %r18, 32 /* r18: 0xc000000000000000 */
+1:
+ /*
+ * Loop over the first 16 SLB entries.
+ * Offset the SLBE into the DMAP, add 16 to the index, and write
+ * it back to the SLB.
+ */
+ /* XXX add more safety checks */
+ slbmfev %r15, %r14
+ slbmfee %r16, %r14
+ or %r16, %r16, %r14 /* index is 0-15 */
+ ori %r16, %r16, 0x10 /* add 16 to index. */
+ or %r16, %r16, %r18 /* SLBE DMAP offset */
+ rldicr %r17, %r16, 0, 37 /* Invalidation SLBE */
+
+ isync
+ slbie %r17
+ /* isync */
+ slbmte %r15, %r16
+ isync
+ addi %r14, %r14, 1
+ cmpdi %r14, 16
+ blt 1b
+
ASENTRY_NOPROF(__restartkernel)
/*
* r3-r7: arguments to go to __start
Modified: head/sys/powerpc/include/db_machdep.h
==============================================================================
--- head/sys/powerpc/include/db_machdep.h Thu May 7 19:19:39 2020
(r360793)
+++ head/sys/powerpc/include/db_machdep.h Thu May 7 19:32:49 2020
(r360794)
@@ -85,8 +85,4 @@ typedef intptr_t db_expr_t; /* expression -
signed */
#define inst_load(ins) 0
#define inst_store(ins) 0
-#ifdef __powerpc64__
-#define DB_STOFFS(offs) ((offs) & ~DMAP_BASE_ADDRESS)
-#endif
-
#endif /* _POWERPC_DB_MACHDEP_H_ */
Modified: head/sys/powerpc/include/param.h
==============================================================================
--- head/sys/powerpc/include/param.h Thu May 7 19:19:39 2020
(r360793)
+++ head/sys/powerpc/include/param.h Thu May 7 19:32:49 2020
(r360794)
@@ -109,6 +109,8 @@
#define MAXPAGESIZES 1 /* maximum number of supported
page sizes */
+#define RELOCATABLE_KERNEL 1 /* kernel may relocate
during startup */
+
#ifndef KSTACK_PAGES
#ifdef __powerpc64__
#define KSTACK_PAGES 8 /* includes pcb */
Modified: head/sys/powerpc/ofw/ofw_initrd.c
==============================================================================
--- head/sys/powerpc/ofw/ofw_initrd.c Thu May 7 19:19:39 2020
(r360793)
+++ head/sys/powerpc/ofw/ofw_initrd.c Thu May 7 19:32:49 2020
(r360794)
@@ -36,6 +36,8 @@ __FBSDID("$FreeBSD$");
#include <vm/pmap.h>
#include <machine/bus.h>
+#include <machine/elf.h>
+#include <machine/param.h>
#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_bus.h>
@@ -58,6 +60,8 @@ ofw_initrd_probe_and_attach(void *junk)
vm_paddr_t start, end;
pcell_t cell[2];
ssize_t size;
+ u_char *taste;
+ Elf_Ehdr ehdr;
if (!hw_direct_map)
return;
@@ -91,7 +95,15 @@ ofw_initrd_probe_and_attach(void *junk)
}
if (end - start > 0) {
- mfs_root = (u_char *) PHYS_TO_DMAP(start);
+ taste = (u_char*) PHYS_TO_DMAP(start);
+ memcpy(&ehdr, taste, sizeof(ehdr));
+
+ if (IS_ELF(ehdr)) {
+ printf("ofw_initrd: initrd is kernel image!\n");
+ return;
+ }
+
+ mfs_root = taste;
mfs_root_size = end - start;
printf("ofw_initrd: initrd loaded at 0x%08lx-0x%08lx\n",
start, end);
Modified: head/sys/powerpc/powerpc/elf32_machdep.c
==============================================================================
--- head/sys/powerpc/powerpc/elf32_machdep.c Thu May 7 19:19:39 2020
(r360793)
+++ head/sys/powerpc/powerpc/elf32_machdep.c Thu May 7 19:32:49 2020
(r360794)
@@ -221,10 +221,10 @@ elf32_dump_thread(struct thread *td, void *dst, size_t
#ifndef __powerpc64__
bool
-elf_is_ifunc_reloc(Elf_Size r_info __unused)
+elf_is_ifunc_reloc(Elf_Size r_info)
{
- return (false);
+ return (ELF_R_TYPE(r_info) == R_PPC_IRELATIVE);
}
/* Process one elf relocation with addend. */
@@ -235,7 +235,7 @@ elf_reloc_internal(linker_file_t lf, Elf_Addr relocbas
Elf_Addr *where;
Elf_Half *hwhere;
Elf_Addr addr;
- Elf_Addr addend;
+ Elf_Addr addend, val;
Elf_Word rtype, symidx;
const Elf_Rela *rela;
int error;
@@ -315,6 +315,13 @@ elf_reloc_internal(linker_file_t lf, Elf_Addr relocbas
if (error != 0)
return -1;
*where = elf_relocaddr(lf, addr + addend);
+ break;
+
+ case R_PPC_IRELATIVE:
+ addr = relocbase + addend;
+ val = ((Elf32_Addr (*)(void))addr)();
+ if (*where != val)
+ *where = val;
break;
default:
Modified: head/sys/powerpc/powerpc/elf64_machdep.c
==============================================================================
--- head/sys/powerpc/powerpc/elf64_machdep.c Thu May 7 19:19:39 2020
(r360793)
+++ head/sys/powerpc/powerpc/elf64_machdep.c Thu May 7 19:32:49 2020
(r360794)
@@ -282,10 +282,10 @@ elf64_dump_thread(struct thread *td, void *dst, size_t
}
bool
-elf_is_ifunc_reloc(Elf_Size r_info __unused)
+elf_is_ifunc_reloc(Elf_Size r_info)
{
- return (false);
+ return (ELF_R_TYPE(r_info) == R_PPC_IRELATIVE);
}
/* Process one elf relocation with addend. */
@@ -295,7 +295,7 @@ elf_reloc_internal(linker_file_t lf, Elf_Addr relocbas
{
Elf_Addr *where;
Elf_Addr addr;
- Elf_Addr addend;
+ Elf_Addr addend, val;
Elf_Word rtype, symidx;
const Elf_Rela *rela;
int error;
@@ -340,6 +340,13 @@ elf_reloc_internal(linker_file_t lf, Elf_Addr relocbas
*where = addr;
#endif
__asm __volatile("dcbst 0,%0; sync" :: "r"(where) : "memory");
+ break;
+
+ case R_PPC_IRELATIVE:
+ addr = relocbase + addend;
+ val = ((Elf64_Addr (*)(void))addr)();
+ if (*where != val)
+ *where = val;
break;
default:
Modified: head/sys/powerpc/powerpc/machdep.c
==============================================================================
--- head/sys/powerpc/powerpc/machdep.c Thu May 7 19:19:39 2020
(r360793)
+++ head/sys/powerpc/powerpc/machdep.c Thu May 7 19:32:49 2020
(r360794)
@@ -113,6 +113,7 @@ __FBSDID("$FreeBSD$");
#include <machine/elf.h>
#include <machine/fpu.h>
#include <machine/hid.h>
+#include <machine/ifunc.h>
#include <machine/kdb.h>
#include <machine/md_var.h>
#include <machine/metadata.h>
@@ -161,6 +162,8 @@ SYSCTL_INT(_machdep, CPU_CACHELINE, cacheline_size,
uintptr_t powerpc_init(vm_offset_t, vm_offset_t, vm_offset_t, void *,
uint32_t);
+static void fake_preload_metadata(void);
+
long Maxmem = 0;
long realmem = 0;
@@ -246,6 +249,11 @@ void aim_early_init(vm_offset_t fdt, vm_offset_t toc,
void aim_cpu_init(vm_offset_t toc);
void booke_cpu_init(void);
+#ifdef DDB
+static void load_external_symtab(void);
+static void displace_symbol_table(vm_offset_t, vm_offset_t, vm_offset_t);
+#endif
+
uintptr_t
powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offset_t ofentry, void *mdp,
uint32_t mdp_cookie)
@@ -254,10 +262,13 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offs
struct cpuref bsp;
vm_offset_t startkernel, endkernel;
char *env;
+ void *kmdp = NULL;
bool ofw_bootargs = false;
+ bool symbols_provided = false;
#ifdef DDB
vm_offset_t ksym_start;
vm_offset_t ksym_end;
+ vm_offset_t ksym_sz;
#endif
/* First guess at start/end kernel positions */
@@ -287,15 +298,29 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offs
#endif
/*
+ * At this point, we are executing in our correct memory space.
+ * Book-E started there, and AIM has done an rfi and restarted
+ * execution from _start.
+ *
+ * We may still be in real mode, however. If we are running out of
+ * the direct map on 64 bit, this is possible to do.
+ */
+
+ /*
* Parse metadata if present and fetch parameters. Must be done
* before console is inited so cninit gets the right value of
* boothowto.
*/
if (mdp != NULL) {
- void *kmdp = NULL;
+ /*
+ * Starting up from loader.
+ *
+ * Full metadata has been provided, but we need to figure
+ * out the correct address to relocate it to.
+ */
char *envp = NULL;
uintptr_t md_offset = 0;
- vm_paddr_t kernelendphys;
+ vm_paddr_t kernelstartphys, kernelendphys;
#ifdef AIM
if ((uintptr_t)&powerpc_init > DMAP_BASE_ADDRESS)
@@ -306,6 +331,7 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offs
preload_metadata = mdp;
if (md_offset > 0) {
+ /* Translate phys offset into DMAP offset. */
preload_metadata += md_offset;
preload_bootstrap_relocate(md_offset);
}
@@ -321,6 +347,9 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offs
if (fdt != 0)
fdt += md_offset;
}
+ kernelstartphys = MD_FETCH(kmdp, MODINFO_ADDR,
+ vm_offset_t);
+ /* kernelstartphys is already relocated. */
kernelendphys = MD_FETCH(kmdp, MODINFOMD_KERNEND,
vm_offset_t);
if (kernelendphys != 0)
@@ -329,13 +358,35 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offs
#ifdef DDB
ksym_start = MD_FETCH(kmdp, MODINFOMD_SSYM, uintptr_t);
ksym_end = MD_FETCH(kmdp, MODINFOMD_ESYM, uintptr_t);
+ ksym_sz = *(Elf_Size*)ksym_start;
+
+ /*
+ * Loader already handled displacing to the load
+ * address, but we still need to displace it to the
+ * DMAP.
+ */
+ displace_symbol_table(
+ (vm_offset_t)(ksym_start + sizeof(Elf_Size)),
+ ksym_sz, md_offset);
+
db_fetch_ksymtab(ksym_start, ksym_end);
+ symbols_provided = true;
#endif
}
} else {
+ /*
+ * Self-loading kernel, we have to fake up metadata.
+ *
+ * Since we are creating the metadata from the final
+ * memory space, we don't need to call
+ * preload_boostrap_relocate().
+ */
+ fake_preload_metadata();
+ kmdp = preload_search_by_type("elf kernel");
init_static_kenv(init_kenv, sizeof(init_kenv));
ofw_bootargs = true;
}
+
/* Store boot environment state */
OF_initial_setup((void *)fdt, NULL, (int (*)(void *))ofentry);
@@ -365,6 +416,11 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offs
*/
OF_bootstrap();
+#ifdef DDB
+ if (!symbols_provided && hw_direct_map)
+ load_external_symtab();
+#endif
+
if (ofw_bootargs)
ofw_parse_bootargs();
@@ -412,6 +468,7 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offs
*/
pmap_bootstrap(startkernel, endkernel);
mtmsr(psl_kernset & ~PSL_EE);
+ link_elf_ireloc(kmdp);
/*
* Initialize params/tunables that are derived from memsize
@@ -447,6 +504,178 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offs
return (((uintptr_t)thread0.td_pcb -
(sizeof(struct callframe) - 3*sizeof(register_t))) & ~15UL);
+}
+
+#ifdef DDB
+/*
+ * XXX Figure out where to move this.
+ */
+static void
+displace_symbol_table(vm_offset_t ksym_start,
+ vm_offset_t ksym_sz, vm_offset_t displacement) {
+ Elf_Sym *sym;
+
+ /*
+ * Relocate the symbol table to our final load address.
+ */
+ for (sym = (Elf_Sym *)ksym_start;
+ (vm_paddr_t)sym < (ksym_start + ksym_sz);
+ sym++) {
+ if (sym->st_name == 0 ||
+ sym->st_shndx == SHN_UNDEF ||
+ sym->st_value == 0)
+ continue;
+ if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT &&
+ ELF_ST_TYPE(sym->st_info) != STT_FUNC &&
+ ELF_ST_TYPE(sym->st_info) != STT_NOTYPE)
+ continue;
+ /* Skip relocating any implausible symbols */
+ if (sym->st_value > KERNBASE)
+ sym->st_value += displacement;
+ }
+}
+
+/*
+ * On powernv, we might not have symbols loaded via loader. However, if the
+ * user passed the kernel in as the initrd as well, we can manually load it
+ * via reinterpreting the initrd copy of the kernel.
+ */
+static void
+load_external_symtab(void) {
+ phandle_t chosen;
+ vm_paddr_t start, end;
+ pcell_t cell[2];
+ ssize_t size;
+ u_char *kernelimg;
+
+ int i;
+
+ Elf_Ehdr *ehdr;
+ Elf_Phdr *phdr;
+ Elf_Shdr *shdr;
+
+ vm_offset_t ksym_start, ksym_sz, kstr_start, kstr_sz;
+
+ if (!hw_direct_map)
+ return;
+
+ chosen = OF_finddevice("/chosen");
+ if (chosen <= 0)
+ return;
+
+ if (!OF_hasprop(chosen, "linux,initrd-start") ||
+ !OF_hasprop(chosen, "linux,initrd-end"))
+ return;
+
+ size = OF_getencprop(chosen, "linux,initrd-start", cell, sizeof(cell));
+ if (size == 4)
+ start = cell[0];
+ else if (size == 8)
+ start = (uint64_t)cell[0] << 32 | cell[1];
+ else
+ return;
+
+ size = OF_getencprop(chosen, "linux,initrd-end", cell, sizeof(cell));
+ if (size == 4)
+ end = cell[0];
+ else if (size == 8)
+ end = (uint64_t)cell[0] << 32 | cell[1];
+ else
+ return;
+
+ if (!(end - start > 0))
+ return;
+
+ kernelimg = (u_char *) PHYS_TO_DMAP(start);
+
+ ehdr = (Elf_Ehdr *)kernelimg;
+
+ if (!IS_ELF(*ehdr))
+ return;
+
+ phdr = (Elf_Phdr *)(kernelimg + ehdr->e_phoff);
+ shdr = (Elf_Shdr *)(kernelimg + ehdr->e_shoff);
+
+ ksym_start = 0;
+ ksym_sz = 0;
+ kstr_start = 0;
+ kstr_sz = 0;
+ for (i = 0; i < ehdr->e_shnum; i++) {
+ if (shdr[i].sh_type == SHT_SYMTAB) {
+ ksym_start = (vm_offset_t)(kernelimg +
+ shdr[i].sh_offset);
+ ksym_sz = (vm_offset_t)(shdr[i].sh_size);
+ kstr_start = (vm_offset_t)(kernelimg +
+ shdr[shdr[i].sh_link].sh_offset);
+ kstr_sz = (vm_offset_t)
+ (shdr[shdr[i].sh_link].sh_size);
+ }
+ }
+
+ if (ksym_start != 0 && kstr_start != 0 && ksym_sz != 0 &&
+ kstr_sz != 0 && ksym_start < kstr_start) {
+
+ displace_symbol_table(ksym_start, ksym_sz,
+ (__startkernel - KERNBASE));
+ ksymtab = ksym_start;
+ ksymtab_size = ksym_sz;
+ kstrtab = kstr_start;
+ }
+
+};
+#endif
+
+/*
+ * When not being loaded from loader, we need to create our own metadata
+ * so we can interact with the kernel linker.
+ */
+static void
+fake_preload_metadata(void) {
+ /* We depend on dword alignment here. */
+ static uint32_t fake_preload[36] __aligned(8);
+ int i = 0;
+
+ fake_preload[i++] = MODINFO_NAME;
+ fake_preload[i++] = strlen("kernel") + 1;
+ strcpy((char*)&fake_preload[i], "kernel");
+ /* ['k' 'e' 'r' 'n'] ['e' 'l' '\0' ..] */
+ i += 2;
+
+ fake_preload[i++] = MODINFO_TYPE;
+ fake_preload[i++] = strlen("elf kernel") + 1;
+ strcpy((char*)&fake_preload[i], "elf kernel");
+ /* ['e' 'l' 'f' ' '] ['k' 'e' 'r' 'n'] ['e' 'l' '\0' ..] */
+ i += 3;
+
+#ifdef __powerpc64__
+ /* Padding -- Fields start on u_long boundaries */
+ fake_preload[i++] = 0;
+#endif
+
+ fake_preload[i++] = MODINFO_ADDR;
+ fake_preload[i++] = sizeof(vm_offset_t);
+ *(vm_offset_t *)&fake_preload[i] =
+ (vm_offset_t)(__startkernel);
+ i += (sizeof(vm_offset_t) / 4);
+
+ fake_preload[i++] = MODINFO_SIZE;
+ fake_preload[i++] = sizeof(vm_offset_t);
+ *(vm_offset_t *)&fake_preload[i] =
+ (vm_offset_t)(__endkernel) - (vm_offset_t)(__startkernel);
+ i += (sizeof(vm_offset_t) / 4);
+
+ /*
+ * MODINFOMD_SSYM and MODINFOMD_ESYM cannot be provided here,
+ * as the memory comes from outside the loaded ELF sections.
+ *
+ * If the symbols are being provided by other means (MFS), the
+ * tables will be loaded into the debugger directly.
+ */
+
+ /* Null field at end to mark end of data. */
+ fake_preload[i++] = 0;
+ fake_preload[i] = 0;
+ preload_metadata = (void*)fake_preload;
}
/*
_______________________________________________
svn-src-all@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
