446c92b290
This is a fix for the following crash observed in 2.6.29-rc3: http://lkml.org/lkml/2009/1/29/150 On ARM it doesn't make sense to trace a naked function because then mcount is called without stack and frame pointer being set up and there is no chance to restore the lr register to the value before mcount was called. Reported-by: Matthias Kaehlcke <matthias@kaehlcke.net> Tested-by: Matthias Kaehlcke <matthias@kaehlcke.net> Cc: Abhishek Sagar <sagar.abhishek@gmail.com> Cc: Steven Rostedt <rostedt@home.goodmis.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
111 lines
3.1 KiB
C
111 lines
3.1 KiB
C
/*
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* linux/arch/arm/mm/copypage-feroceon.S
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*
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* Copyright (C) 2008 Marvell Semiconductors
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This handles copy_user_highpage and clear_user_page on Feroceon
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* more optimally than the generic implementations.
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*/
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#include <linux/init.h>
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#include <linux/highmem.h>
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static void __naked
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feroceon_copy_user_page(void *kto, const void *kfrom)
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{
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asm("\
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stmfd sp!, {r4-r9, lr} \n\
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mov ip, %0 \n\
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1: mov lr, r1 \n\
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ldmia r1!, {r2 - r9} \n\
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pld [lr, #32] \n\
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pld [lr, #64] \n\
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pld [lr, #96] \n\
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pld [lr, #128] \n\
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pld [lr, #160] \n\
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pld [lr, #192] \n\
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pld [lr, #224] \n\
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stmia r0, {r2 - r9} \n\
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ldmia r1!, {r2 - r9} \n\
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mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
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add r0, r0, #32 \n\
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stmia r0, {r2 - r9} \n\
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ldmia r1!, {r2 - r9} \n\
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mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
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add r0, r0, #32 \n\
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stmia r0, {r2 - r9} \n\
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ldmia r1!, {r2 - r9} \n\
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mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
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add r0, r0, #32 \n\
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stmia r0, {r2 - r9} \n\
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ldmia r1!, {r2 - r9} \n\
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mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
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add r0, r0, #32 \n\
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stmia r0, {r2 - r9} \n\
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ldmia r1!, {r2 - r9} \n\
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mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
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add r0, r0, #32 \n\
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stmia r0, {r2 - r9} \n\
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ldmia r1!, {r2 - r9} \n\
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mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
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add r0, r0, #32 \n\
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stmia r0, {r2 - r9} \n\
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ldmia r1!, {r2 - r9} \n\
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mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
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add r0, r0, #32 \n\
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stmia r0, {r2 - r9} \n\
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subs ip, ip, #(32 * 8) \n\
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mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D line\n\
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add r0, r0, #32 \n\
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bne 1b \n\
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mcr p15, 0, ip, c7, c10, 4 @ drain WB\n\
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ldmfd sp!, {r4-r9, pc}"
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:
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: "I" (PAGE_SIZE));
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}
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void feroceon_copy_user_highpage(struct page *to, struct page *from,
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unsigned long vaddr)
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{
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void *kto, *kfrom;
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kto = kmap_atomic(to, KM_USER0);
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kfrom = kmap_atomic(from, KM_USER1);
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feroceon_copy_user_page(kto, kfrom);
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kunmap_atomic(kfrom, KM_USER1);
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kunmap_atomic(kto, KM_USER0);
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}
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void feroceon_clear_user_highpage(struct page *page, unsigned long vaddr)
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{
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void *ptr, *kaddr = kmap_atomic(page, KM_USER0);
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asm volatile ("\
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mov r1, %2 \n\
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mov r2, #0 \n\
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mov r3, #0 \n\
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mov r4, #0 \n\
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mov r5, #0 \n\
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mov r6, #0 \n\
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mov r7, #0 \n\
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mov ip, #0 \n\
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mov lr, #0 \n\
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1: stmia %0, {r2-r7, ip, lr} \n\
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subs r1, r1, #1 \n\
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mcr p15, 0, %0, c7, c14, 1 @ clean and invalidate D line\n\
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add %0, %0, #32 \n\
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bne 1b \n\
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mcr p15, 0, r1, c7, c10, 4 @ drain WB"
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: "=r" (ptr)
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: "0" (kaddr), "I" (PAGE_SIZE / 32)
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: "r1", "r2", "r3", "r4", "r5", "r6", "r7", "ip", "lr");
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kunmap_atomic(kaddr, KM_USER0);
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}
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struct cpu_user_fns feroceon_user_fns __initdata = {
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.cpu_clear_user_highpage = feroceon_clear_user_highpage,
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.cpu_copy_user_highpage = feroceon_copy_user_highpage,
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};
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