diff options
Diffstat (limited to 'arch/mips/kernel/crash_dump.c')
| -rw-r--r-- | arch/mips/kernel/crash_dump.c | 41 |
1 files changed, 6 insertions, 35 deletions
diff --git a/arch/mips/kernel/crash_dump.c b/arch/mips/kernel/crash_dump.c index 01b2bd95ba1f..2e50f55185a6 100644 --- a/arch/mips/kernel/crash_dump.c +++ b/arch/mips/kernel/crash_dump.c @@ -1,11 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/highmem.h> -#include <linux/memblock.h> #include <linux/crash_dump.h> -#include <linux/uaccess.h> -#include <linux/slab.h> - -static void *kdump_buf_page; /** * copy_oldmem_page - copy one page from "oldmem" @@ -19,10 +14,6 @@ static void *kdump_buf_page; * * Copy a page from "oldmem". For this page, there is no pte mapped * in the current kernel. - * - * Calling copy_to_user() in atomic context is not desirable. Hence first - * copying the data to a pre-allocated kernel page and then copying to user - * space in non-atomic context. */ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, unsigned long offset, int userbuf) @@ -32,36 +23,16 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, if (!csize) return 0; - vaddr = kmap_atomic_pfn(pfn); + vaddr = kmap_local_pfn(pfn); if (!userbuf) { - memcpy(buf, (vaddr + offset), csize); - kunmap_atomic(vaddr); + memcpy(buf, vaddr + offset, csize); } else { - if (!kdump_buf_page) { - pr_warn("Kdump: Kdump buffer page not allocated\n"); - - return -EFAULT; - } - copy_page(kdump_buf_page, vaddr); - kunmap_atomic(vaddr); - if (copy_to_user(buf, (kdump_buf_page + offset), csize)) - return -EFAULT; + if (copy_to_user(buf, vaddr + offset, csize)) + csize = -EFAULT; } - return csize; -} - -static int __init kdump_buf_page_init(void) -{ - int ret = 0; + kunmap_local(vaddr); - kdump_buf_page = kmalloc(PAGE_SIZE, GFP_KERNEL); - if (!kdump_buf_page) { - pr_warn("Kdump: Failed to allocate kdump buffer page\n"); - ret = -ENOMEM; - } - - return ret; + return csize; } -arch_initcall(kdump_buf_page_init); |