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![Vivek Goyal](/assets/img/avatar_default.png)
o elfcorehdr_addr is used by not only the code under CONFIG_PROC_VMCORE but also by the code which is not inside CONFIG_PROC_VMCORE. For example, is_kdump_kernel() is used by powerpc code to determine if kernel is booting after a panic then use previous kernel's TCE table. So even if CONFIG_PROC_VMCORE is not set in second kernel, one should be able to correctly determine that we are booting after a panic and setup calgary iommu accordingly. o So remove the assumption that elfcorehdr_addr is under CONFIG_PROC_VMCORE. o Move definition of elfcorehdr_addr to arch dependent crash files. (Unfortunately crash dump does not have an arch independent file otherwise that would have been the best place). o kexec.c is not the right place as one can Have CRASH_DUMP enabled in second kernel without KEXEC being enabled. o I don't see sh setup code parsing the command line for elfcorehdr_addr. I am wondering how does vmcore interface work on sh. Anyway, I am atleast defining elfcoredhr_addr so that compilation is not broken on sh. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Simon Horman <horms@verge.net.au> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
53 lines
1.6 KiB
C
53 lines
1.6 KiB
C
/*
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* kernel/crash_dump.c - Memory preserving reboot related code.
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*
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* Created by: Simon Horman <horms@verge.net.au>
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* Original code moved from kernel/crash.c
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* Original code comment copied from the i386 version of this file
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*/
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#include <linux/errno.h>
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#include <linux/types.h>
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#include <linux/crash_dump.h>
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#include <asm/page.h>
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#include <asm/uaccess.h>
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/* Stores the physical address of elf header of crash image. */
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unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
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/**
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* copy_oldmem_page - copy one page from "oldmem"
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* @pfn: page frame number to be copied
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* @buf: target memory address for the copy; this can be in kernel address
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* space or user address space (see @userbuf)
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* @csize: number of bytes to copy
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* @offset: offset in bytes into the page (based on pfn) to begin the copy
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* @userbuf: if set, @buf is in user address space, use copy_to_user(),
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* otherwise @buf is in kernel address space, use memcpy().
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*
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* Copy a page from "oldmem". For this page, there is no pte mapped
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* in the current kernel. We stitch up a pte, similar to kmap_atomic.
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*
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* Calling copy_to_user() in atomic context is not desirable. Hence first
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* copying the data to a pre-allocated kernel page and then copying to user
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* space in non-atomic context.
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*/
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ssize_t
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copy_oldmem_page(unsigned long pfn, char *buf,
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size_t csize, unsigned long offset, int userbuf)
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{
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void *vaddr;
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if (!csize)
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return 0;
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vaddr = __va(pfn<<PAGE_SHIFT);
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if (userbuf) {
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if (copy_to_user(buf, (vaddr + offset), csize)) {
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return -EFAULT;
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}
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} else
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memcpy(buf, (vaddr + offset), csize);
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return csize;
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}
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