From 4d5ade5b29c618e97a8988efb6967cb4dd0e2183 Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Fri, 27 Apr 2007 11:25:57 +0900 Subject: [PATCH] sh: kdump support. This adds support for kexec based crash dumps. Signed-off-by: Paul Mundt --- arch/sh/Kconfig | 14 +++++++++++ arch/sh/kernel/Makefile | 1 + arch/sh/kernel/crash_dump.c | 46 ++++++++++++++++++++++++++++++++++ arch/sh/kernel/machine_kexec.c | 29 ++++++++++++++++++--- arch/sh/kernel/setup.c | 6 +++++ include/asm-sh/kexec.h | 42 +++++++++++++++++++++++++++---- 6 files changed, 129 insertions(+), 9 deletions(-) create mode 100644 arch/sh/kernel/crash_dump.c diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig index 0b465d622cfc..dfdfaae6772f 100644 --- a/arch/sh/Kconfig +++ b/arch/sh/Kconfig @@ -551,6 +551,20 @@ config KEXEC support. As of this writing the exact hardware interface is strongly in flux, so no good recommendation can be made. +config CRASH_DUMP + bool "kernel crash dumps (EXPERIMENTAL)" + depends on EXPERIMENTAL + help + Generate crash dump after being started by kexec. + This should be normally only set in special crash dump kernels + which are loaded in the main kernel with kexec-tools into + a specially reserved region and then later executed after + a crash by kdump/kexec. The crash dump kernel must be compiled + to a memory address not used by the main kernel using + MEMORY_START. + + For more details see Documentation/kdump/kdump.txt + config SMP bool "Symmetric multi-processing support" ---help--- diff --git a/arch/sh/kernel/Makefile b/arch/sh/kernel/Makefile index ff30d7f58043..9104b6257644 100644 --- a/arch/sh/kernel/Makefile +++ b/arch/sh/kernel/Makefile @@ -20,5 +20,6 @@ obj-$(CONFIG_SH_CPU_FREQ) += cpufreq.o obj-$(CONFIG_MODULES) += module.o obj-$(CONFIG_EARLY_PRINTK) += early_printk.o obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o +obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_PM) += pm.o obj-$(CONFIG_STACKTRACE) += stacktrace.o diff --git a/arch/sh/kernel/crash_dump.c b/arch/sh/kernel/crash_dump.c new file mode 100644 index 000000000000..4a2ecbe27d8e --- /dev/null +++ b/arch/sh/kernel/crash_dump.c @@ -0,0 +1,46 @@ +/* + * crash_dump.c - Memory preserving reboot related code. + * + * Created by: Hariprasad Nellitheertha (hari@in.ibm.com) + * Copyright (C) IBM Corporation, 2004. All rights reserved + */ + +#include +#include +#include +#include + +/** + * copy_oldmem_page - copy one page from "oldmem" + * @pfn: page frame number to be copied + * @buf: target memory address for the copy; this can be in kernel address + * space or user address space (see @userbuf) + * @csize: number of bytes to copy + * @offset: offset in bytes into the page (based on pfn) to begin the copy + * @userbuf: if set, @buf is in user address space, use copy_to_user(), + * otherwise @buf is in kernel address space, use memcpy(). + * + * Copy a page from "oldmem". For this page, there is no pte mapped + * in the current kernel. We stitch up a pte, similar to kmap_atomic. + */ +ssize_t copy_oldmem_page(unsigned long pfn, char *buf, + size_t csize, unsigned long offset, int userbuf) +{ + void *vaddr; + + if (!csize) + return 0; + + vaddr = ioremap(pfn << PAGE_SHIFT, PAGE_SIZE); + + if (userbuf) { + if (copy_to_user(buf, (vaddr + offset), csize)) { + iounmap(vaddr); + return -EFAULT; + } + } else + memcpy(buf, (vaddr + offset), csize); + + iounmap(vaddr); + return csize; +} diff --git a/arch/sh/kernel/machine_kexec.c b/arch/sh/kernel/machine_kexec.c index 08587cdb64d6..790ed69b8666 100644 --- a/arch/sh/kernel/machine_kexec.c +++ b/arch/sh/kernel/machine_kexec.c @@ -59,13 +59,13 @@ static void kexec_info(struct kimage *image) printk(" segment[%d]: 0x%08x - 0x%08x (0x%08x)\n", i, (unsigned int)image->segment[i].mem, - (unsigned int)image->segment[i].mem + image->segment[i].memsz, + (unsigned int)image->segment[i].mem + + image->segment[i].memsz, (unsigned int)image->segment[i].memsz); - } + } printk(" start : 0x%08x\n\n", (unsigned int)image->start); } - /* * Do not allocate memory (or fail in any way) in machine_kexec(). * We are past the point of no return, committed to rebooting now. @@ -101,6 +101,27 @@ NORET_TYPE void machine_kexec(struct kimage *image) /* now call it */ rnk = (relocate_new_kernel_t) reboot_code_buffer; - (*rnk)(page_list, reboot_code_buffer, image->start, vbr_reg); + (*rnk)(page_list, reboot_code_buffer, image->start, vbr_reg); } +/* crashkernel=size@addr specifies the location to reserve for + * a crash kernel. By reserving this memory we guarantee + * that linux never sets it up as a DMA target. + * Useful for holding code to do something appropriate + * after a kernel panic. + */ +static int __init parse_crashkernel(char *arg) +{ + unsigned long size, base; + size = memparse(arg, &arg); + if (*arg == '@') { + base = memparse(arg+1, &arg); + /* FIXME: Do I want a sanity check + * to validate the memory range? + */ + crashk_res.start = base; + crashk_res.end = base + size - 1; + } + return 0; +} +early_param("crashkernel", parse_crashkernel); diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c index cab91a7665da..477d2a854fc4 100644 --- a/arch/sh/kernel/setup.c +++ b/arch/sh/kernel/setup.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -287,6 +288,11 @@ void __init setup_bootmem_allocator(unsigned long start_pfn) } } #endif +#ifdef CONFIG_KEXEC + if (crashk_res.start != crashk_res.end) + reserve_bootmem(crashk_res.start, + crashk_res.end - crashk_res.start + 1); +#endif } #ifndef CONFIG_NEED_MULTIPLE_NODES diff --git a/include/asm-sh/kexec.h b/include/asm-sh/kexec.h index 9d235af20cdd..da36a7548601 100644 --- a/include/asm-sh/kexec.h +++ b/include/asm-sh/kexec.h @@ -1,5 +1,8 @@ -#ifndef _SH_KEXEC_H -#define _SH_KEXEC_H +#ifndef __ASM_SH_KEXEC_H +#define __ASM_SH_KEXEC_H + +#include +#include /* * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return. @@ -25,8 +28,37 @@ #define MAX_NOTE_BYTES 1024 -/* Provide a dummy definition to avoid build failures. */ static inline void crash_setup_regs(struct pt_regs *newregs, - struct pt_regs *oldregs) { } + struct pt_regs *oldregs) +{ + if (oldregs) + memcpy(newregs, oldregs, sizeof(*newregs)); + else { + __asm__ __volatile__ ("mov r0, %0" : "=r" (newregs->regs[0])); + __asm__ __volatile__ ("mov r1, %0" : "=r" (newregs->regs[1])); + __asm__ __volatile__ ("mov r2, %0" : "=r" (newregs->regs[2])); + __asm__ __volatile__ ("mov r3, %0" : "=r" (newregs->regs[3])); + __asm__ __volatile__ ("mov r4, %0" : "=r" (newregs->regs[4])); + __asm__ __volatile__ ("mov r5, %0" : "=r" (newregs->regs[5])); + __asm__ __volatile__ ("mov r6, %0" : "=r" (newregs->regs[6])); + __asm__ __volatile__ ("mov r7, %0" : "=r" (newregs->regs[7])); + __asm__ __volatile__ ("mov r8, %0" : "=r" (newregs->regs[8])); + __asm__ __volatile__ ("mov r9, %0" : "=r" (newregs->regs[9])); + __asm__ __volatile__ ("mov r10, %0" : "=r" (newregs->regs[10])); + __asm__ __volatile__ ("mov r11, %0" : "=r" (newregs->regs[11])); + __asm__ __volatile__ ("mov r12, %0" : "=r" (newregs->regs[12])); + __asm__ __volatile__ ("mov r13, %0" : "=r" (newregs->regs[13])); + __asm__ __volatile__ ("mov r14, %0" : "=r" (newregs->regs[14])); + __asm__ __volatile__ ("mov r15, %0" : "=r" (newregs->regs[15])); -#endif /* _SH_KEXEC_H */ + __asm__ __volatile__ ("sts pr, %0" : "=r" (newregs->pr)); + __asm__ __volatile__ ("sts macl, %0" : "=r" (newregs->macl)); + __asm__ __volatile__ ("sts mach, %0" : "=r" (newregs->mach)); + + __asm__ __volatile__ ("stc gbr, %0" : "=r" (newregs->gbr)); + __asm__ __volatile__ ("stc sr, %0" : "=r" (newregs->sr)); + + newregs->pc = (unsigned long)current_text_addr(); + } +} +#endif /* __ASM_SH_KEXEC_H */