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185aed7557
With the PMB enabled, only P1SEG and up are covered by the PMB mappings, meaning that situations where out-of-bounds physical addresses are read from will lead to TLB reset after the PMB miss, allowing for use cases like dd if=/dev/mem to reset the TLB. Fix this up to make sure the reference is between __MEMORY_START (phys) and __pa(high_memory). This is coherent across all variants of sh/sh64 with and without MMU, though the PMB bug itself is only applicable to SH-4A parts. Reported-by: Hideo Saito <saito@densan.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
32 lines
690 B
C
32 lines
690 B
C
/*
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* arch/sh/mm/mmap.c
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*
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* Copyright (C) 2008 Paul Mundt
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*/
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#include <linux/io.h>
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#include <linux/mm.h>
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#include <asm/page.h>
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/*
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* You really shouldn't be using read() or write() on /dev/mem. This
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* might go away in the future.
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*/
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int valid_phys_addr_range(unsigned long addr, size_t count)
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{
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if (addr < (PAGE_OFFSET + (PFN_START << PAGE_SHIFT)))
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return 0;
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if (addr + count > __pa(high_memory))
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return 0;
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return 1;
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}
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int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
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{
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return 1;
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}
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