On Thursday 19 October 2006 00:38, you wrote:
> On Wed, Oct 18, 2006 at 11:21:21PM +0200, Nicolas Schichan wrote:
> + sys sys_kexec_load 1
>
> The last column is the number of arguments slots of the syscall as counted
> by the MIPS argument passing conventions, so this should actually be 4.
> Not this was actually a harmless bug; it does hurt for syscalls that need
> more than 4 slots.
This is fixed in the patch following.
> diff -Nru linux-orig/arch/mips/kernel/scall64-n32.S
> linux-work/arch/mips/kernel/scall64-n32.S ---
> linux-orig/arch/mips/kernel/scall64-n32.S 2006-10-14 05:34:03.000000000
> +0200 +++ linux-work/arch/mips/kernel/scall64-n32.S 2006-10-17
> 15:58:59.000000000 +0200 @@ -392,3 +392,4 @@
> PTR sys_tee
> PTR sys_vmsplice /* 6271 */
> PTR sys_move_pages
> + PTR sys_kexec_load
> diff -Nru linux-orig/arch/mips/kernel/scall64-o32.S
> linux-work/arch/mips/kernel/scall64-o32.S ---
> linux-orig/arch/mips/kernel/scall64-o32.S 2006-10-14 05:34:03.000000000
> +0200 +++ linux-work/arch/mips/kernel/scall64-o32.S 2006-10-17
> 15:59:23.000000000 +0200 @@ -514,4 +514,5 @@
> PTR sys_tee
> PTR sys_vmsplice
> PTR compat_sys_move_pages
> + PTR sys_kexec_load
> .size sys_call_table,.-sys_call_table
>
> That is these two being 32-bit syscalls on a 64-bit kernel need to use the
> compat_sys_kexec_load syscall wrapper to work right.
This is fixed too in the patch following.
> And finally there are the syscall numbers. The ones you've picked are
> already taken, so I've choosen:
>
> O32 ABI: 4311
> N64 ABI: 5270
> N32 ABI: 6270
The patch following updates scall*.S files accordingly. however as the patch
is against 2.6.18 kernel I had to pad the holes in the syscall table with
sys_ni_syscall.
> Note I'll allocate these syscalls immediately to give ABI stability - it's
> a standard Linux syscall afterall. So you can drop the unistd.h bits from
> your patch.
ok, the unistd.h changes are dropped in the attached patch.
I also made CONFIG_KEXEC depend on !CONFIG_SMP.
Signed-off-by: Nicolas Schichan <nschichan@xxxxxxxxxx>
diff -Nrup linux-orig/arch/mips/Kconfig linux-work/arch/mips/Kconfig
--- linux-orig/arch/mips/Kconfig 2006-10-14 05:34:03.000000000 +0200
+++ linux-work/arch/mips/Kconfig 2006-10-19 15:18:18.000000000 +0200
@@ -820,6 +820,23 @@ config TOSHIBA_RBTX4938
endchoice
+config KEXEC
+ bool "Kexec system call (EXPERIMENTAL)"
+ depends on EXPERIMENTAL && !SMP
+ help
+ kexec is a system call that implements the ability to shutdown your
+ current kernel, and to start another kernel. It is like a reboot
+ but it is indepedent of the system firmware. And like a reboot
+ you can start any kernel with it, not just Linux.
+
+ The name comes from the similiarity to the exec system call.
+
+ It is an ongoing process to be certain the hardware in a machine
+ is properly shutdown, so do not be surprised if this code does not
+ initially work for you. It may help to enable device hotplugging
+ support. As of this writing the exact hardware interface is
+ strongly in flux, so no good recommendation can be made.
+
source "arch/mips/ddb5xxx/Kconfig"
source "arch/mips/gt64120/ev64120/Kconfig"
source "arch/mips/jazz/Kconfig"
diff -Nrup linux-orig/arch/mips/kernel/machine_kexec.c linux-work/arch/mips/kernel/machine_kexec.c
--- linux-orig/arch/mips/kernel/machine_kexec.c 1970-01-01 01:00:00.000000000 +0100
+++ linux-work/arch/mips/kernel/machine_kexec.c 2006-10-19 15:38:01.000000000 +0200
@@ -0,0 +1,79 @@
+/*
+ * machine_kexec.c for kexec
+ * Created by <nschichan@xxxxxxxxxx> on Thu Oct 12 15:15:06 2006
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#include <linux/kexec.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+
+#include <asm/cacheflush.h>
+#include <asm/page.h>
+
+const extern unsigned char relocate_new_kernel[];
+const extern unsigned int relocate_new_kernel_size;
+
+extern unsigned long kexec_start_address;
+extern unsigned long kexec_indirection_page;
+
+int
+machine_kexec_prepare(struct kimage *kimage)
+{
+ return 0;
+}
+
+void
+machine_kexec_cleanup(struct kimage *kimage)
+{
+}
+
+void
+machine_shutdown(void)
+{
+}
+
+void
+machine_crash_shutdown(struct pt_regs *regs)
+{
+}
+
+void
+machine_kexec(struct kimage *image)
+{
+ unsigned long reboot_code_buffer;
+ unsigned long entry;
+ unsigned long *ptr;
+
+ reboot_code_buffer =
+ (unsigned long)page_address(image->control_code_page);
+
+ kexec_start_address = image->start;
+ kexec_indirection_page =
+ (unsigned long)phys_to_virt(image->head & PAGE_MASK);
+
+ memcpy((void*)reboot_code_buffer, relocate_new_kernel,
+ relocate_new_kernel_size);
+
+ /*
+ * The generic kexec code builds a page list with physical
+ * addresses. they are directly accessible through KSEG0 (or
+ * XKSEG0 or XPHYS if on 64bit system), hence the
+ * pys_to_virt() call.
+ */
+ for (ptr = &image->head; (entry = *ptr) && !(entry &IND_DONE);
+ ptr = (entry & IND_INDIRECTION) ?
+ phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
+ if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
+ *ptr & IND_DESTINATION)
+ *ptr = (unsigned long)phys_to_virt(*ptr);
+ }
+
+ printk("Will call new kernel at %08lx\n", image->start);
+ printk("Bye ...\n");
+ flush_cache_all();
+ local_irq_disable();
+ ((void (*)(void))reboot_code_buffer)();
+}
diff -Nrup linux-orig/arch/mips/kernel/Makefile linux-work/arch/mips/kernel/Makefile
--- linux-orig/arch/mips/kernel/Makefile 2006-10-14 05:34:03.000000000 +0200
+++ linux-work/arch/mips/kernel/Makefile 2006-10-17 15:55:11.000000000 +0200
@@ -66,6 +66,8 @@ obj-$(CONFIG_64BIT) += cpu-bugs64.o
obj-$(CONFIG_I8253) += i8253.o
+obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o
+
CFLAGS_cpu-bugs64.o = $(shell if $(CC) $(CFLAGS) -Wa,-mdaddi -c -o /dev/null -xc /dev/null >/dev/null 2>&1; then echo "-DHAVE_AS_SET_DADDI"; fi)
EXTRA_AFLAGS := $(CFLAGS)
diff -Nrup linux-orig/arch/mips/kernel/relocate_kernel.S linux-work/arch/mips/kernel/relocate_kernel.S
--- linux-orig/arch/mips/kernel/relocate_kernel.S 1970-01-01 01:00:00.000000000 +0100
+++ linux-work/arch/mips/kernel/relocate_kernel.S 2006-10-19 15:37:53.000000000 +0200
@@ -0,0 +1,80 @@
+/*
+ * relocate_kernel.S for kexec
+ * Created by <nschichan@xxxxxxxxxx> on Thu Oct 12 17:49:57 2006
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/regdef.h>
+#include <asm/page.h>
+#include <asm/mipsregs.h>
+#include <asm/stackframe.h>
+#include <asm/addrspace.h>
+
+ .globl relocate_new_kernel
+relocate_new_kernel:
+
+ PTR_L s0, kexec_indirection_page
+ PTR_L s1, kexec_start_address
+
+process_entry:
+ PTR_L s2, (s0)
+ PTR_ADD s0, s0, SZREG
+
+ /* destination page */
+ and s3, s2, 0x1
+ beq s3, zero, 1f
+ and s4, s2, ~0x1 /* store destination addr in s4 */
+ move a0, s4
+ b process_entry
+
+1:
+ /* indirection page, update s0 */
+ and s3, s2, 0x2
+ beq s3, zero, 1f
+ and s0, s2, ~0x2
+ b process_entry
+
+1:
+ /* done page */
+ and s3, s2, 0x4
+ beq s3, zero, 1f
+ b done
+1:
+ /* source page */
+ and s3, s2, 0x8
+ beq s3, zero, process_entry
+ and s2, s2, ~0x8
+ li s6, (1 << PAGE_SHIFT) / SZREG
+
+copy_word:
+ /* copy page word by word */
+ REG_L s5, (s2)
+ REG_S s5, (s4)
+ INT_ADD s4, s4, SZREG
+ INT_ADD s2, s2, SZREG
+ INT_SUB s6, s6, 1
+ beq s6, zero, process_entry
+ b copy_word
+ b process_entry
+
+done:
+ /* jump to kexec_start_address */
+ j s1
+
+ .globl kexec_start_address
+kexec_start_address:
+ .long 0x0
+
+ .globl kexec_indirection_page
+kexec_indirection_page:
+ .long 0x0
+
+relocate_new_kernel_end:
+
+ .globl relocate_new_kernel_size
+relocate_new_kernel_size:
+ .long relocate_new_kernel_end - relocate_new_kernel
diff -Nrup linux-orig/arch/mips/kernel/scall32-o32.S linux-work/arch/mips/kernel/scall32-o32.S
--- linux-orig/arch/mips/kernel/scall32-o32.S 2006-10-14 05:34:03.000000000 +0200
+++ linux-work/arch/mips/kernel/scall32-o32.S 2006-10-19 15:10:39.000000000 +0200
@@ -662,6 +662,9 @@ einval: li v0, -EINVAL
sys sys_tee 4
sys sys_vmsplice 4
sys sys_move_pages 6
+ sys sys_ni_syscall 0
+ sys sys_ni_syscall 0 /* 4310 */
+ sys sys_kexec_load 4
.endm
/* We pre-compute the number of _instruction_ bytes needed to
diff -Nrup linux-orig/arch/mips/kernel/scall64-64.S linux-work/arch/mips/kernel/scall64-64.S
--- linux-orig/arch/mips/kernel/scall64-64.S 2006-10-14 05:34:03.000000000 +0200
+++ linux-work/arch/mips/kernel/scall64-64.S 2006-10-19 15:14:27.000000000 +0200
@@ -466,3 +466,6 @@ sys_call_table:
PTR sys_tee /* 5265 */
PTR sys_vmsplice
PTR sys_move_pages
+ PTR sys_ni_syscall
+ PTR sys_ni_syscall
+ PTR sys_kexec_load /* 5270 */
diff -Nrup linux-orig/arch/mips/kernel/scall64-n32.S linux-work/arch/mips/kernel/scall64-n32.S
--- linux-orig/arch/mips/kernel/scall64-n32.S 2006-10-14 05:34:03.000000000 +0200
+++ linux-work/arch/mips/kernel/scall64-n32.S 2006-10-19 15:17:44.000000000 +0200
@@ -390,5 +390,8 @@ EXPORT(sysn32_call_table)
PTR sys_splice
PTR sys_sync_file_range
PTR sys_tee
- PTR sys_vmsplice /* 6271 */
+ PTR sys_vmsplice /* 6270 */
PTR sys_move_pages
+ PTR sys_ni_syscall
+ PTR sys_ni_syscall
+ PTR compat_sys_kexec_load
diff -Nrup linux-orig/arch/mips/kernel/scall64-o32.S linux-work/arch/mips/kernel/scall64-o32.S
--- linux-orig/arch/mips/kernel/scall64-o32.S 2006-10-14 05:34:03.000000000 +0200
+++ linux-work/arch/mips/kernel/scall64-o32.S 2006-10-19 15:17:54.000000000 +0200
@@ -514,4 +514,7 @@ sys_call_table:
PTR sys_tee
PTR sys_vmsplice
PTR compat_sys_move_pages
+ PTR sys_ni_syscall
+ PTR sys_ni_syscall /* 4310 */
+ PTR compat_sys_kexec_load
.size sys_call_table,.-sys_call_table
diff -Nrup linux-orig/include/asm-mips/kexec.h linux-work/include/asm-mips/kexec.h
--- linux-orig/include/asm-mips/kexec.h 1970-01-01 01:00:00.000000000 +0100
+++ linux-work/include/asm-mips/kexec.h 2006-10-19 15:38:15.000000000 +0200
@@ -0,0 +1,32 @@
+/*
+ * kexec.h for kexec
+ * Created by <nschichan@xxxxxxxxxx> on Thu Oct 12 14:59:34 2006
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#ifndef _MIPS_KEXEC
+# define _MIPS_KEXEC
+
+/* Maximum physical address we can use pages from */
+#define KEXEC_SOURCE_MEMORY_LIMIT (HIGHMEM_START)
+/* Maximum address we can reach in physical address mode */
+#define KEXEC_DESTINATION_MEMORY_LIMIT (HIGHMEM_START)
+ /* Maximum address we can use for the control code buffer */
+#define KEXEC_CONTROL_MEMORY_LIMIT (HIGHMEM_START)
+
+#define KEXEC_CONTROL_CODE_SIZE 4096
+
+/* The native architecture */
+#define KEXEC_ARCH KEXEC_ARCH_MIPS
+
+#define MAX_NOTE_BYTES 1024
+
+static inline void crash_setup_regs(struct pt_regs *newregs,
+ struct pt_regs *oldregs)
+{
+ /* Dummy implementation for now */
+}
+
+#endif /* !_MIPS_KEXEC */
diff -Nrup linux-orig/include/linux/kexec.h linux-work/include/linux/kexec.h
--- linux-orig/include/linux/kexec.h 2006-10-14 05:34:03.000000000 +0200
+++ linux-work/include/linux/kexec.h 2006-10-17 16:21:49.000000000 +0200
@@ -122,6 +122,8 @@ extern struct kimage *kexec_crash_image;
#define KEXEC_ARCH_IA_64 (50 << 16)
#define KEXEC_ARCH_S390 (22 << 16)
#define KEXEC_ARCH_SH (42 << 16)
+#define KEXEC_ARCH_MIPS_LE (10 << 16)
+#define KEXEC_ARCH_MIPS ( 8 << 16)
#define KEXEC_FLAGS (KEXEC_ON_CRASH) /* List of defined/legal kexec flags */
--
Nicolas Schichan
